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linux-stable/drivers/base/regmap/regcache-rbtree.c

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regmap: add proper SPDX identifiers on files that did not have them. There were a few files in the regmap code that did not have SPDX identifiers on them, so fix that up. At the same time, remove the "free form" text that specified the license of the file, as that is impossible for any tool to properly parse. Also, as Mark loves // comment markers, convert all of the headers to be the same to make things look consistent :) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-04-25 18:06:18 +00:00
// SPDX-License-Identifier: GPL-2.0
//
// Register cache access API - rbtree caching support
//
// Copyright 2011 Wolfson Microelectronics plc
//
// Author: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
#include <linux/debugfs.h>
regmap: cache: Sort include headers alphabetically If the inlcude headers aren't sorted alphabetically, then the logical choice is to append new ones, however that creates a lot of potential for conflicts or duplicates because every change will then add new includes in the same location. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-09 09:02:52 +00:00
#include <linux/device.h>
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
#include <linux/rbtree.h>
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
#include <linux/seq_file.h>
regmap: cache: Sort include headers alphabetically If the inlcude headers aren't sorted alphabetically, then the logical choice is to append new ones, however that creates a lot of potential for conflicts or duplicates because every change will then add new includes in the same location. Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-09 09:02:52 +00:00
#include <linux/slab.h>
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
#include "internal.h"
static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
unsigned int value);
regmap: Do not call regcache_exit from regcache_rbtree_init error path Calling regcache_exit from regcache_rbtree_init is first of all a layering violation and secondly will cause double frees. regcache_exit will free buffers allocated by the core, but the core will also free the same buffers when the cacheops init callback returns an error. Thus we end up with a double free. Fix this by not calling regcache_exit but only free those buffers which, have been allocated in this function. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-15 12:34:40 +00:00
static int regcache_rbtree_exit(struct regmap *map);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct regcache_rbtree_node {
/* block of adjacent registers */
void *block;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
/* Which registers are present */
long *cache_present;
regmap: rbtree: improve 64bits memory alignment Change regcache_rbtree_node strcuture fields order to align the pointers on 64bits architectures. Signed-off-by: Jean-Christophe PINCE <jean-christophe.pince@intel.com> Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 20:26:48 +00:00
/* base register handled by this block */
unsigned int base_reg;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* number of registers available in the block */
unsigned int blklen;
regmap: rbtree: improve 64bits memory alignment Change regcache_rbtree_node strcuture fields order to align the pointers on 64bits architectures. Signed-off-by: Jean-Christophe PINCE <jean-christophe.pince@intel.com> Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-01 20:26:48 +00:00
/* the actual rbtree node holding this block */
struct rb_node node;
regmap: Remove attribute packed from struct 'regcache_rbtree_node' On one hand commit 28644c809f44 ("regmap: Add the rbtree cache support") added 'regcache_rbtree_node' as packed structure, while on the other hand commit e977145aeaad ("[RBTREE] Add explicit alignment to sizeof(long) for struct rb_node.") declared struct 'rb_node' as aligned. Solve the ambiguity of placing aligned structure in a packed one by removing the packed attribute from struct. This seems to be the behavior of gcc anyway. This removes the following warning (W=1): drivers/base/regmap/regcache-rbtree.c:36:1: warning: alignment 1 of 'struct regcache_rbtree_node' is less than 4 [-Wpacked-not-aligned] Cc: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2019-01-24 18:06:24 +00:00
};
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct regcache_rbtree_ctx {
struct rb_root root;
struct regcache_rbtree_node *cached_rbnode;
};
static inline void regcache_rbtree_get_base_top_reg(
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
struct regmap *map,
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct regcache_rbtree_node *rbnode,
unsigned int *base, unsigned int *top)
{
*base = rbnode->base_reg;
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
*top = rbnode->base_reg + ((rbnode->blklen - 1) * map->reg_stride);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
static unsigned int regcache_rbtree_get_register(struct regmap *map,
struct regcache_rbtree_node *rbnode, unsigned int idx)
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
{
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
return regcache_get_val(map, rbnode->block, idx);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
static void regcache_rbtree_set_register(struct regmap *map,
struct regcache_rbtree_node *rbnode,
unsigned int idx, unsigned int val)
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
{
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
set_bit(idx, rbnode->cache_present);
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
regcache_set_val(map, rbnode->block, idx, val);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
static struct regcache_rbtree_node *regcache_rbtree_lookup(struct regmap *map,
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
unsigned int reg)
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
{
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct rb_node *node;
struct regcache_rbtree_node *rbnode;
unsigned int base_reg, top_reg;
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
rbnode = rbtree_ctx->cached_rbnode;
if (rbnode) {
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
&top_reg);
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
if (reg >= base_reg && reg <= top_reg)
return rbnode;
}
node = rbtree_ctx->root.rb_node;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
while (node) {
regmap: use rb_entry() To make the code clearer, use rb_entry() instead of container_of() to deal with rbtree. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-19 14:40:25 +00:00
rbnode = rb_entry(node, struct regcache_rbtree_node, node);
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
&top_reg);
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
if (reg >= base_reg && reg <= top_reg) {
rbtree_ctx->cached_rbnode = rbnode;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
return rbnode;
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
} else if (reg > top_reg) {
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
node = node->rb_right;
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
} else if (reg < base_reg) {
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
node = node->rb_left;
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
return NULL;
}
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
static int regcache_rbtree_insert(struct regmap *map, struct rb_root *root,
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct regcache_rbtree_node *rbnode)
{
struct rb_node **new, *parent;
struct regcache_rbtree_node *rbnode_tmp;
unsigned int base_reg_tmp, top_reg_tmp;
unsigned int base_reg;
parent = NULL;
new = &root->rb_node;
while (*new) {
regmap: use rb_entry() To make the code clearer, use rb_entry() instead of container_of() to deal with rbtree. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-19 14:40:25 +00:00
rbnode_tmp = rb_entry(*new, struct regcache_rbtree_node, node);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* base and top registers of the current rbnode */
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
regcache_rbtree_get_base_top_reg(map, rbnode_tmp, &base_reg_tmp,
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
&top_reg_tmp);
/* base register of the rbnode to be added */
base_reg = rbnode->base_reg;
parent = *new;
/* if this register has already been inserted, just return */
if (base_reg >= base_reg_tmp &&
base_reg <= top_reg_tmp)
return 0;
else if (base_reg > top_reg_tmp)
new = &((*new)->rb_right);
else if (base_reg < base_reg_tmp)
new = &((*new)->rb_left);
}
/* insert the node into the rbtree */
rb_link_node(&rbnode->node, parent, new);
rb_insert_color(&rbnode->node, root);
return 1;
}
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
#ifdef CONFIG_DEBUG_FS
static int rbtree_show(struct seq_file *s, void *ignored)
{
struct regmap *map = s->private;
struct regcache_rbtree_ctx *rbtree_ctx = map->cache;
struct regcache_rbtree_node *n;
struct rb_node *node;
unsigned int base, top;
regmap: rbtree Expose total memory consumption in the rbtree debugfs entry Provide a feel of how much overhead the rbtree cache adds to the game. [Slightly reworded output in debugfs -- broonie] Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12 17:26:49 +00:00
size_t mem_size;
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
int nodes = 0;
int registers = 0;
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
int this_registers, average;
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
regmap: regcache: Fixup locking for custom lock callbacks The parameter passed to the regmap lock/unlock callbacks needs to be map->lock_arg, regcache passes just map. This works fine in the case that no custom locking callbacks are used since in this case map->lock_arg equals map, but will break when custom locking callbacks are used. The issue was introduced in commit 0d4529c5("regmap: make lock/unlock functions customizable") and is fixed by this patch. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-23 15:23:49 +00:00
map->lock(map->lock_arg);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
regmap: rbtree Expose total memory consumption in the rbtree debugfs entry Provide a feel of how much overhead the rbtree cache adds to the game. [Slightly reworded output in debugfs -- broonie] Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12 17:26:49 +00:00
mem_size = sizeof(*rbtree_ctx);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
for (node = rb_first(&rbtree_ctx->root); node != NULL;
node = rb_next(node)) {
regmap: use rb_entry() To make the code clearer, use rb_entry() instead of container_of() to deal with rbtree. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-19 14:40:25 +00:00
n = rb_entry(node, struct regcache_rbtree_node, node);
regmap: rbtree Expose total memory consumption in the rbtree debugfs entry Provide a feel of how much overhead the rbtree cache adds to the game. [Slightly reworded output in debugfs -- broonie] Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12 17:26:49 +00:00
mem_size += sizeof(*n);
mem_size += (n->blklen * map->cache_word_size);
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
mem_size += BITS_TO_LONGS(n->blklen) * sizeof(long);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
regcache_rbtree_get_base_top_reg(map, n, &base, &top);
this_registers = ((top - base) / map->reg_stride) + 1;
seq_printf(s, "%x-%x (%d)\n", base, top, this_registers);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
nodes++;
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
registers += this_registers;
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
}
regmap: prevent division by zero in rbtree_show If there are no nodes in the cache, nodes will be 0, so calculating "registers / nodes" will cause division by zero. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@vger.kernel.org
2012-04-04 21:48:33 +00:00
if (nodes)
average = registers / nodes;
else
average = 0;
regmap: rbtree Expose total memory consumption in the rbtree debugfs entry Provide a feel of how much overhead the rbtree cache adds to the game. [Slightly reworded output in debugfs -- broonie] Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-12 17:26:49 +00:00
seq_printf(s, "%d nodes, %d registers, average %d registers, used %zu bytes\n",
nodes, registers, average, mem_size);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
regmap: regcache: Fixup locking for custom lock callbacks The parameter passed to the regmap lock/unlock callbacks needs to be map->lock_arg, regcache passes just map. This works fine in the case that no custom locking callbacks are used since in this case map->lock_arg equals map, but will break when custom locking callbacks are used. The issue was introduced in commit 0d4529c5("regmap: make lock/unlock functions customizable") and is fixed by this patch. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-23 15:23:49 +00:00
map->unlock(map->lock_arg);
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
return 0;
}
regmap: rbtree: convert to DEFINE_SHOW_ATTRIBUTE Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-15 08:38:37 +00:00
DEFINE_SHOW_ATTRIBUTE(rbtree);
regmap: Fix rbtreee build when not using debugfs The debugfs functions don't stub themselves out quite so well as might be desirable so provide functions which do do this stubbing. Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-22 11:33:31 +00:00
static void rbtree_debugfs_init(struct regmap *map)
{
debugfs_create_file("rbtree", 0400, map->debugfs, map, &rbtree_fops);
}
regmap: Provide debugfs dump of the rbtree cache data Show the register ranges we have in each rbtree node in debugfs, plus some statistics on how big each node is and the total number of nodes. It may also be worth collecting data on the ranges of dirty registers to see if there's much mileage in trying to coalesce writes on sync. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-21 19:44:44 +00:00
#endif
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
static int regcache_rbtree_init(struct regmap *map)
{
struct regcache_rbtree_ctx *rbtree_ctx;
int i;
int ret;
map->cache = kmalloc(sizeof *rbtree_ctx, GFP_KERNEL);
if (!map->cache)
return -ENOMEM;
rbtree_ctx = map->cache;
rbtree_ctx->root = RB_ROOT;
rbtree_ctx->cached_rbnode = NULL;
for (i = 0; i < map->num_reg_defaults; i++) {
ret = regcache_rbtree_write(map,
map->reg_defaults[i].reg,
map->reg_defaults[i].def);
if (ret)
goto err;
}
return 0;
err:
regmap: Do not call regcache_exit from regcache_rbtree_init error path Calling regcache_exit from regcache_rbtree_init is first of all a layering violation and secondly will cause double frees. regcache_exit will free buffers allocated by the core, but the core will also free the same buffers when the cacheops init callback returns an error. Thus we end up with a double free. Fix this by not calling regcache_exit but only free those buffers which, have been allocated in this function. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-11-15 12:34:40 +00:00
regcache_rbtree_exit(map);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
return ret;
}
static int regcache_rbtree_exit(struct regmap *map)
{
struct rb_node *next;
struct regcache_rbtree_ctx *rbtree_ctx;
struct regcache_rbtree_node *rbtree_node;
/* if we've already been called then just return */
rbtree_ctx = map->cache;
if (!rbtree_ctx)
return 0;
/* free up the rbtree */
next = rb_first(&rbtree_ctx->root);
while (next) {
rbtree_node = rb_entry(next, struct regcache_rbtree_node, node);
next = rb_next(&rbtree_node->node);
rb_erase(&rbtree_node->node, &rbtree_ctx->root);
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
kfree(rbtree_node->cache_present);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
kfree(rbtree_node->block);
kfree(rbtree_node);
}
/* release the resources */
kfree(map->cache);
map->cache = NULL;
return 0;
}
static int regcache_rbtree_read(struct regmap *map,
unsigned int reg, unsigned int *value)
{
struct regcache_rbtree_node *rbnode;
unsigned int reg_tmp;
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
rbnode = regcache_rbtree_lookup(map, reg);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
if (rbnode) {
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
reg_tmp = (reg - rbnode->base_reg) / map->reg_stride;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
if (!test_bit(reg_tmp, rbnode->cache_present))
regmap: Cut down on the average # of nodes in the rbtree cache This patch aims to bring down the average number of nodes in the rbtree cache and increase the average number of registers per node. This should improve general lookup and traversal times. This is achieved by setting the minimum size of a block within the rbnode to the size of the rbnode itself. This will essentially cache possibly non-existent registers so to combat this scenario, we keep a separate bitmap in memory which keeps track of which register exists. The memory overhead of this change is likely in the order of ~5-10%, possibly less depending on the register file layout. On my test system with a bitmap of ~4300 bits and a relatively sparse register layout, the memory requirements for the entire cache did not increase (the cutting down of nodes which was about 50% of the original number compensated the situation). A second patch that can be built on top of this can look at the ratio `sizeof(*rbnode) / map->cache_word_size' in order to suitably adjust the block length of each block. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-15 14:54:35 +00:00
return -ENOENT;
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
*value = regcache_rbtree_get_register(map, rbnode, reg_tmp);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
} else {
regmap: Return a sensible error code if we fail to read the cache If a register isn't cached then let callers know that so they can fall back or error handle appropriately. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2011-10-09 12:23:31 +00:00
return -ENOENT;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
return 0;
}
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
static int regcache_rbtree_insert_to_block(struct regmap *map,
struct regcache_rbtree_node *rbnode,
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
unsigned int base_reg,
unsigned int top_reg,
unsigned int reg,
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
unsigned int value)
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
{
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
unsigned int blklen;
unsigned int pos, offset;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
unsigned long *present;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
u8 *blk;
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
blklen = (top_reg - base_reg) / map->reg_stride + 1;
pos = (reg - base_reg) / map->reg_stride;
offset = (rbnode->base_reg - base_reg) / map->reg_stride;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
blk = krealloc(rbnode->block,
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
blklen * map->cache_word_size,
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
GFP_KERNEL);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
if (!blk)
return -ENOMEM;
regmap: Fix possible double-free in regcache_rbtree_exit() In regcache_rbtree_insert_to_block(), when 'present' realloc failed, the 'blk' which is supposed to assign to 'rbnode->block' will be freed, so 'rbnode->block' points a freed memory, in the error handling path of regcache_rbtree_init(), 'rbnode->block' will be freed again in regcache_rbtree_exit(), KASAN will report double-free as follows: BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 Call Trace: slab_free_freelist_hook+0x10d/0x240 kfree+0xce/0x390 regcache_rbtree_exit+0x15d/0x1a0 regcache_rbtree_init+0x224/0x2c0 regcache_init+0x88d/0x1310 __regmap_init+0x3151/0x4a80 __devm_regmap_init+0x7d/0x100 madera_spi_probe+0x10f/0x333 [madera_spi] spi_probe+0x183/0x210 really_probe+0x285/0xc30 To fix this, moving up the assignment of rbnode->block to immediately after the reallocation has succeeded so that the data structure stays valid even if the second reallocation fails. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 3f4ff561bc88b ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20211012023735.1632786-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2021-10-12 02:37:35 +00:00
rbnode->block = blk;
regmap: regcache-rbtree: Clean new present bits on present bitmap resize When inserting a new register into a block, the present bit map size is increased using krealloc. krealloc does not clear the additionally allocated memory, leaving it filled with random values. Result is that some registers are considered cached even though this is not the case. Fix the problem by clearing the additionally allocated memory. Also, if the bitmap size does not increase, do not reallocate the bitmap at all to reduce overhead. Fixes: 3f4ff561bc88 ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-07-27 04:34:50 +00:00
if (BITS_TO_LONGS(blklen) > BITS_TO_LONGS(rbnode->blklen)) {
present = krealloc(rbnode->cache_present,
BITS_TO_LONGS(blklen) * sizeof(*present),
GFP_KERNEL);
regmap: Fix possible double-free in regcache_rbtree_exit() In regcache_rbtree_insert_to_block(), when 'present' realloc failed, the 'blk' which is supposed to assign to 'rbnode->block' will be freed, so 'rbnode->block' points a freed memory, in the error handling path of regcache_rbtree_init(), 'rbnode->block' will be freed again in regcache_rbtree_exit(), KASAN will report double-free as follows: BUG: KASAN: double-free or invalid-free in kfree+0xce/0x390 Call Trace: slab_free_freelist_hook+0x10d/0x240 kfree+0xce/0x390 regcache_rbtree_exit+0x15d/0x1a0 regcache_rbtree_init+0x224/0x2c0 regcache_init+0x88d/0x1310 __regmap_init+0x3151/0x4a80 __devm_regmap_init+0x7d/0x100 madera_spi_probe+0x10f/0x333 [madera_spi] spi_probe+0x183/0x210 really_probe+0x285/0xc30 To fix this, moving up the assignment of rbnode->block to immediately after the reallocation has succeeded so that the data structure stays valid even if the second reallocation fails. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 3f4ff561bc88b ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20211012023735.1632786-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2021-10-12 02:37:35 +00:00
if (!present)
regmap: regcache-rbtree: Clean new present bits on present bitmap resize When inserting a new register into a block, the present bit map size is increased using krealloc. krealloc does not clear the additionally allocated memory, leaving it filled with random values. Result is that some registers are considered cached even though this is not the case. Fix the problem by clearing the additionally allocated memory. Also, if the bitmap size does not increase, do not reallocate the bitmap at all to reduce overhead. Fixes: 3f4ff561bc88 ("regmap: rbtree: Make cache_present bitmap per node") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-07-27 04:34:50 +00:00
return -ENOMEM;
memset(present + BITS_TO_LONGS(rbnode->blklen), 0,
(BITS_TO_LONGS(blklen) - BITS_TO_LONGS(rbnode->blklen))
* sizeof(*present));
} else {
present = rbnode->cache_present;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* insert the register value in the correct place in the rbnode block */
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
if (pos == 0) {
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
memmove(blk + offset * map->cache_word_size,
blk, rbnode->blklen * map->cache_word_size);
regmap: regcache-rbtree: Fix present bitmap resize When inserting a new register into a block at the lower end the present bitmap is currently shifted into the wrong direction. The effect of this is that the bitmap becomes corrupted and registers which are present might be reported as not present and vice versa. Fix this by shifting left rather than right. Fixes: 472fdec7380c("regmap: rbtree: Reduce number of nodes, take 2") Reported-by: Daniel Baluta <daniel.baluta@gmail.com> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-03-07 16:10:01 +00:00
bitmap_shift_left(present, present, offset, blklen);
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* update the rbnode block, its size and the base register */
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
rbnode->blklen = blklen;
rbnode->base_reg = base_reg;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
rbnode->cache_present = present;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
regcache_rbtree_set_register(map, rbnode, pos, value);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
return 0;
}
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
static struct regcache_rbtree_node *
regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
{
struct regcache_rbtree_node *rbnode;
regmap: rbtree: Use range information to allocate nodes If range information has been provided then when we allocate a rbnode within a range allocate the entire range. The goal is to minimise the number of reallocations done when combining or extending blocks. At present only readability and yes_ranges are taken into account, this is expected to cover most cases efficiently. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:25 +00:00
const struct regmap_range *range;
int i;
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
if (!rbnode)
return NULL;
regmap: rbtree: Use range information to allocate nodes If range information has been provided then when we allocate a rbnode within a range allocate the entire range. The goal is to minimise the number of reallocations done when combining or extending blocks. At present only readability and yes_ranges are taken into account, this is expected to cover most cases efficiently. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:25 +00:00
/* If there is a read table then use it to guess at an allocation */
if (map->rd_table) {
for (i = 0; i < map->rd_table->n_yes_ranges; i++) {
if (regmap_reg_in_range(reg,
&map->rd_table->yes_ranges[i]))
break;
}
if (i != map->rd_table->n_yes_ranges) {
range = &map->rd_table->yes_ranges[i];
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
rbnode->blklen = (range->range_max - range->range_min) /
map->reg_stride + 1;
regmap: rbtree: Use range information to allocate nodes If range information has been provided then when we allocate a rbnode within a range allocate the entire range. The goal is to minimise the number of reallocations done when combining or extending blocks. At present only readability and yes_ranges are taken into account, this is expected to cover most cases efficiently. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:25 +00:00
rbnode->base_reg = range->range_min;
}
}
if (!rbnode->blklen) {
regmap: rbtree: Fix overlapping rbnodes. Avoid overlapping register regions by making the initial blklen of a new node 1. If a register write occurs to a yet uncached register, that is lower than but near an existing node's base_reg, a new node is created and it's blklen is set to an arbitrary value (sizeof(*rbnode)). That may cause this node to overlap with another node. Those nodes should be merged, but this merge doesn't happen yet, so this patch at least makes the initial blklen small enough to avoid hitting the wrong node, which may otherwise lead to severe breakage. Signed-off-by: David Jander <david@protonic.nl> Signed-off-by: Mark Brown <broonie@linaro.org> Cc: stable@vger.kernel.org
2013-08-21 15:37:22 +00:00
rbnode->blklen = 1;
regmap: rbtree: Use range information to allocate nodes If range information has been provided then when we allocate a rbnode within a range allocate the entire range. The goal is to minimise the number of reallocations done when combining or extending blocks. At present only readability and yes_ranges are taken into account, this is expected to cover most cases efficiently. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:25 +00:00
rbnode->base_reg = reg;
}
regmap: replace kmalloc with kmalloc_array Replace kmalloc with specialized function kmalloc_array when the size is a multiplication of : number * size Signed-off-by: lixiubo <lixiubo@cmss.chinamobile.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-20 10:06:30 +00:00
rbnode->block = kmalloc_array(rbnode->blklen, map->cache_word_size,
GFP_KERNEL);
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
if (!rbnode->block)
goto err_free;
regmap: replace kzalloc with kcalloc Replace kzalloc with specialized function kcalloc when the size is a multiplication of : number * sizeof Signed-off-by: lixiubo <lixiubo@cmss.chinamobile.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-20 10:06:29 +00:00
rbnode->cache_present = kcalloc(BITS_TO_LONGS(rbnode->blklen),
sizeof(*rbnode->cache_present),
GFP_KERNEL);
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
if (!rbnode->cache_present)
goto err_free_block;
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
return rbnode;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
err_free_block:
kfree(rbnode->block);
err_free:
kfree(rbnode);
return NULL;
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
unsigned int value)
{
struct regcache_rbtree_ctx *rbtree_ctx;
struct regcache_rbtree_node *rbnode, *rbnode_tmp;
struct rb_node *node;
unsigned int reg_tmp;
int ret;
rbtree_ctx = map->cache;
regmap: Cut down on the average # of nodes in the rbtree cache This patch aims to bring down the average number of nodes in the rbtree cache and increase the average number of registers per node. This should improve general lookup and traversal times. This is achieved by setting the minimum size of a block within the rbnode to the size of the rbnode itself. This will essentially cache possibly non-existent registers so to combat this scenario, we keep a separate bitmap in memory which keeps track of which register exists. The memory overhead of this change is likely in the order of ~5-10%, possibly less depending on the register file layout. On my test system with a bitmap of ~4300 bits and a relatively sparse register layout, the memory requirements for the entire cache did not increase (the cutting down of nodes which was about 50% of the original number compensated the situation). A second patch that can be built on top of this can look at the ratio `sizeof(*rbnode) / map->cache_word_size' in order to suitably adjust the block length of each block. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-03-15 14:54:35 +00:00
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* if we can't locate it in the cached rbnode we'll have
* to traverse the rbtree looking for it.
*/
regmap: rbtree-cache: Move cached rbnode handling into lookup function Move the handling of the cached rbnode into regcache_rbtree_lookup. This allows us to remove of some duplicated code sections in regcache_rbtree_read and regcache_rbtree_write. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-27 18:15:38 +00:00
rbnode = regcache_rbtree_lookup(map, reg);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
if (rbnode) {
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
reg_tmp = (reg - rbnode->base_reg) / map->reg_stride;
regmap: cache: Pass the map rather than the word size when updating values It's more idiomatic to pass the map structure around and this means we can use other bits of information from the map. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-21 18:03:13 +00:00
regcache_rbtree_set_register(map, rbnode, reg_tmp, value);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
} else {
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
unsigned int base_reg, top_reg;
unsigned int new_base_reg, new_top_reg;
unsigned int min, max;
unsigned int max_dist;
regmap: rbtree: Avoid overlapping nodes When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-04 15:22:16 +00:00
unsigned int dist, best_dist = UINT_MAX;
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
max_dist = map->reg_stride * sizeof(*rbnode_tmp) /
map->cache_word_size;
if (reg < max_dist)
min = 0;
else
min = reg - max_dist;
max = reg + max_dist;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
/* look for an adjacent register to the one we are about to add */
regmap: rbtree: When adding a reg do a bsearch for target node A binary search is much more efficient rather than iterating over the rbtree in ascending order which the current code is doing. During initialisation the reg defaults are written to the cache in a large chunk and these are always sorted in the ascending order so for this situation ideally we should have iterated the rbtree in descending order. But at runtime the drivers may write into the cache in any random order so this patch selects to use a bsearch to give an optimal runtime performance and also at initialisation time when reg defaults are written the performance of binary search would be much better than iterating in ascending order which the current code was doing. Signed-off-by: Nikesh Oswal <Nikesh.Oswal@wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-21 13:16:14 +00:00
node = rbtree_ctx->root.rb_node;
while (node) {
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
rbnode_tmp = rb_entry(node, struct regcache_rbtree_node,
node);
regmap: rbtree: Simplify adjacent node look-up A register which is adjacent to a node will either be left to the first register or right to the last register. It will not be within the node's range, so there is no point in checking for each register cached by the node whether the new register is next to it. It is sufficient to check whether the register comes before the first register or after the last register of the node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:32 +00:00
regcache_rbtree_get_base_top_reg(map, rbnode_tmp,
&base_reg, &top_reg);
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
if (base_reg <= max && top_reg >= min) {
regmap: rbtree: Avoid overlapping nodes When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-04 15:22:16 +00:00
if (reg < base_reg)
dist = base_reg - reg;
else if (reg > top_reg)
dist = reg - top_reg;
regmap: rbtree: When adding a reg do a bsearch for target node A binary search is much more efficient rather than iterating over the rbtree in ascending order which the current code is doing. During initialisation the reg defaults are written to the cache in a large chunk and these are always sorted in the ascending order so for this situation ideally we should have iterated the rbtree in descending order. But at runtime the drivers may write into the cache in any random order so this patch selects to use a bsearch to give an optimal runtime performance and also at initialisation time when reg defaults are written the performance of binary search would be much better than iterating in ascending order which the current code was doing. Signed-off-by: Nikesh Oswal <Nikesh.Oswal@wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-21 13:16:14 +00:00
else
regmap: rbtree: Avoid overlapping nodes When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-04 15:22:16 +00:00
dist = 0;
if (dist < best_dist) {
rbnode = rbnode_tmp;
best_dist = dist;
new_base_reg = min(reg, base_reg);
new_top_reg = max(reg, top_reg);
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: rbtree: Simplify adjacent node look-up A register which is adjacent to a node will either be left to the first register or right to the last register. It will not be within the node's range, so there is no point in checking for each register cached by the node whether the new register is next to it. It is sufficient to check whether the register comes before the first register or after the last register of the node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:32 +00:00
regmap: rbtree: Avoid overlapping nodes When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-04 15:22:16 +00:00
/*
* Keep looking, we want to choose the closest block,
* otherwise we might end up creating overlapping
* blocks, which breaks the rbtree.
*/
if (reg < base_reg)
node = node->rb_left;
else if (reg > top_reg)
node = node->rb_right;
else
break;
}
if (rbnode) {
ret = regcache_rbtree_insert_to_block(map, rbnode,
regmap: rbtree: Reduce number of nodes, take 2 Support for reducing the number of nodes and memory consumption of the rbtree cache by allowing for small unused holes in the node's register cache block was initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes in the rbtree cache"). But the commit had problems and so its effect was reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes."). This patch brings the feature back of reducing the average number of nodes, which will speedup node look-up, while at the same time also reducing the memory usage of the rbtree cache. This patch takes a slightly different approach than the original patch though. It modifies the adjacent node look-up to not only consider nodes that are just one to the left or the right of the register but any node that falls in a certain range around the register. The range is calculated based on how much memory it would take to allocate a new node compared to how much memory it takes adding a set of unused registers to an existing node. E.g. if a node takes up 24 bytes and each register in a block uses 1 byte the range will be from the register address - 24 to the register address + 24. If we find a node that falls within this range it is cheaper or as expensive to add the register to the existing node and have a couple of unused registers in the node's cache compared to allocating a new node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:33 +00:00
new_base_reg,
new_top_reg, reg,
value);
regmap: rbtree: Simplify adjacent node look-up A register which is adjacent to a node will either be left to the first register or right to the last register. It will not be within the node's range, so there is no point in checking for each register cached by the node whether the new register is next to it. It is sufficient to check whether the register comes before the first register or after the last register of the node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:32 +00:00
if (ret)
return ret;
regmap: rbtree: Avoid overlapping nodes When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-04 15:22:16 +00:00
rbtree_ctx->cached_rbnode = rbnode;
regmap: rbtree: Simplify adjacent node look-up A register which is adjacent to a node will either be left to the first register or right to the last register. It will not be within the node's range, so there is no point in checking for each register cached by the node whether the new register is next to it. It is sufficient to check whether the register comes before the first register or after the last register of the node. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:32 +00:00
return 0;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
/* We did not manage to find a place to insert it in
* an existing block so create a new rbnode.
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
*/
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
rbnode = regcache_rbtree_node_alloc(map, reg);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
if (!rbnode)
return -ENOMEM;
regmap: rbtree: Factor out node allocation In preparation for being slightly smarter about how we allocate memory factor out the node allocation. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-05-08 12:55:24 +00:00
regcache_rbtree_set_register(map, rbnode,
reg - rbnode->base_reg, value);
regmap: implement register striding regmap_config.reg_stride is introduced. All extant register addresses are a multiple of this value. Users of serial-oriented regmap busses will typically set this to 1. Users of the MMIO regmap bus will typically set this based on the value size of their registers, in bytes, so 4 for a 32-bit register. Throughout the regmap code, actual register addresses are used. Wherever the register address is used to index some array of values, the address is divided by the stride to determine the index, or vice-versa. Error- checking is added to all entry-points for register address data to ensure that register addresses actually satisfy the specified stride. The MMIO bus ensures that the specified stride is large enough for the register size. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-04-09 19:40:24 +00:00
regcache_rbtree_insert(map, &rbtree_ctx->root, rbnode);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
rbtree_ctx->cached_rbnode = rbnode;
}
return 0;
}
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
static int regcache_rbtree_sync(struct regmap *map, unsigned int min,
unsigned int max)
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
{
struct regcache_rbtree_ctx *rbtree_ctx;
struct rb_node *node;
struct regcache_rbtree_node *rbnode;
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
unsigned int base_reg, top_reg;
unsigned int start, end;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
int ret;
rbtree_ctx = map->cache;
for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
rbnode = rb_entry(node, struct regcache_rbtree_node, node);
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
&top_reg);
if (base_reg > max)
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
break;
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
if (top_reg < min)
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
continue;
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
if (min > base_reg)
start = (min - base_reg) / map->reg_stride;
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
else
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
start = 0;
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
regcache-rbtree: Fix reg_stride != 1 There are a couple of calculations, which convert between register addresses and block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which assume that reg_stride is 1. This will break the rb cache for configurations which do not use a reg_stride of 1. Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with 'base_reg'. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-27 11:03:03 +00:00
if (max < top_reg)
end = (max - base_reg) / map->reg_stride + 1;
regmap: Supply ranges to the sync operations In order to allow us to support partial sync operations add minimum and maximum register arguments to the sync operation and update the rbtree and lzo caches to use this new information. The LZO implementation is obviously not good, we could exit the iteration earlier, but there may be room for more wide reaching optimisation there. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-02-23 19:31:04 +00:00
else
end = rbnode->blklen;
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
ret = regcache_sync_block(map, rbnode->block,
rbnode->cache_present,
rbnode->base_reg, start, end);
regmap: cache: Factor out block sync The idea of holding blocks of registers in device format is shared between at least rbtree and lzo cache formats so split out the loop that does the sync from the rbtree code so optimisations on it can be reused. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2013-03-29 19:32:28 +00:00
if (ret != 0)
return ret;
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: cache: Factor out block sync The idea of holding blocks of registers in device format is shared between at least rbtree and lzo cache formats so split out the loop that does the sync from the rbtree code so optimisations on it can be reused. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
2013-03-29 19:32:28 +00:00
return regmap_async_complete(map);
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
}
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
static int regcache_rbtree_drop(struct regmap *map, unsigned int min,
unsigned int max)
{
struct regcache_rbtree_ctx *rbtree_ctx;
struct regcache_rbtree_node *rbnode;
struct rb_node *node;
unsigned int base_reg, top_reg;
unsigned int start, end;
rbtree_ctx = map->cache;
for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
rbnode = rb_entry(node, struct regcache_rbtree_node, node);
regcache_rbtree_get_base_top_reg(map, rbnode, &base_reg,
&top_reg);
if (base_reg > max)
break;
if (top_reg < min)
continue;
if (min > base_reg)
start = (min - base_reg) / map->reg_stride;
else
start = 0;
if (max < top_reg)
end = (max - base_reg) / map->reg_stride + 1;
else
end = rbnode->blklen;
bitmap_clear(rbnode->cache_present, start, end - start);
}
return 0;
}
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
struct regcache_ops regcache_rbtree_ops = {
.type = REGCACHE_RBTREE,
.name = "rbtree",
.init = regcache_rbtree_init,
.exit = regcache_rbtree_exit,
regmap: Fix regcache debugfs initialization Commit 6cfec04bcc05 ("regmap: Separate regmap dev initialization") moved the regmap debugfs initialization after regcache initialization. This means that the regmap debugfs directory is not created yet when the cache initialization runs and so any debugfs files registered by the regcache are created in the debugfs root directory rather than the debugfs directory of the regmap instance. Fix this by adding a separate callback for the regcache debugfs initialization which will be called after the parent debugfs entry has been created. Fixes: 6cfec04bcc05 (regmap: Separate regmap dev initialization) Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org> Cc: stable@vger.kernel.org
2014-08-24 13:32:27 +00:00
#ifdef CONFIG_DEBUG_FS
.debugfs_init = rbtree_debugfs_init,
#endif
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
.read = regcache_rbtree_read,
.write = regcache_rbtree_write,
regmap: rbtree: Make cache_present bitmap per node With devices which have a dense and small register map but placed at a large offset the global cache_present bitmap imposes a huge memory overhead. Making the cache_present per rbtree node avoids the issue and easily reduces the memory footprint by a factor of ten. For devices with a more sparse map or without a large base register offset the memory usage might increase slightly by a few bytes, but not significantly. E.g. for a device which has ~50 registers at offset 0x4000 the memory footprint of the register cache goes down form 2496 bytes to 175 bytes. Moving the bitmap to a per node basis means that the handling of the bitmap is now cache implementation specific and can no longer be managed by the core. The regcache_sync_block() function is extended by a additional parameter so that the cache implementation can tell the core which registers in the block are set and which are not. The parameter is optional and if NULL the core assumes that all registers are set. The rbtree cache also needs to implement its own drop callback instead of relying on the core to handle this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-29 08:26:34 +00:00
.sync = regcache_rbtree_sync,
.drop = regcache_rbtree_drop,
regmap: Add the rbtree cache support This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-09-19 13:34:02 +00:00
};
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