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![Frank Rowand](/assets/img/avatar_default.png)
Create a cache of the nodes that contain a phandle property. Use this cache to find the node for a given phandle value instead of scanning the devicetree to find the node. If the phandle value is not found in the cache, of_find_node_by_phandle() will fall back to the tree scan algorithm. The cache is initialized in of_core_init(). The cache is freed via a late_initcall_sync() if modules are not enabled. If the devicetree is created by the dtc compiler, with all phandle property values auto generated, then the size required by the cache could be 4 * (1 + number of phandles) bytes. This results in an O(1) node lookup cost for a given phandle value. Due to a concern that the phandle property values might not be consistent with what is generated by the dtc compiler, a mask has been added to the cache lookup algorithm. To maintain the O(1) node lookup cost, the size of the cache has been increased by rounding the number of entries up to the next power of two. The overhead of finding the devicetree node containing a given phandle value has been noted by several people in the recent past, in some cases with a patch to add a hashed index of devicetree nodes, based on the phandle value of the node. One concern with this approach is the extra space added to each node. This patch takes advantage of the phandle property values auto generated by the dtc compiler, which begin with one and monotonically increase by one, resulting in a range of 1..n for n phandle values. This implementation should also provide a good reduction of overhead for any range of phandle values that are mostly in a monotonic range. Performance measurements by Chintan Pandya <cpandya@codeaurora.org> of several implementations of patches that are similar to this one suggest an expected reduction of boot time by ~400ms for his test system. If the cache size was decreased to 64 entries, the boot time was reduced by ~340 ms. The measurements were on a 4.9.73 kernel for arch/arm64/boot/dts/qcom/sda670-mtp.dts, contains 2371 nodes and 814 phandle values. Reported-by: Chintan Pandya <cpandya@codeaurora.org> Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Rob Herring <robh@kernel.org>
1997 lines
51 KiB
C
1997 lines
51 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Procedures for creating, accessing and interpreting the device tree.
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*
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* Paul Mackerras August 1996.
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* Copyright (C) 1996-2005 Paul Mackerras.
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*
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* Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
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* {engebret|bergner}@us.ibm.com
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*
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* Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
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*
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* Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
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* Grant Likely.
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*/
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#define pr_fmt(fmt) "OF: " fmt
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#include <linux/console.h>
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#include <linux/ctype.h>
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#include <linux/cpu.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/of_graph.h>
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#include <linux/spinlock.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/proc_fs.h>
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#include "of_private.h"
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LIST_HEAD(aliases_lookup);
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struct device_node *of_root;
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EXPORT_SYMBOL(of_root);
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struct device_node *of_chosen;
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struct device_node *of_aliases;
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struct device_node *of_stdout;
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static const char *of_stdout_options;
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struct kset *of_kset;
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/*
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* Used to protect the of_aliases, to hold off addition of nodes to sysfs.
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* This mutex must be held whenever modifications are being made to the
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* device tree. The of_{attach,detach}_node() and
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* of_{add,remove,update}_property() helpers make sure this happens.
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*/
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DEFINE_MUTEX(of_mutex);
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/* use when traversing tree through the child, sibling,
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* or parent members of struct device_node.
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*/
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DEFINE_RAW_SPINLOCK(devtree_lock);
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int of_n_addr_cells(struct device_node *np)
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{
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u32 cells;
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do {
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if (np->parent)
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np = np->parent;
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if (!of_property_read_u32(np, "#address-cells", &cells))
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return cells;
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} while (np->parent);
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/* No #address-cells property for the root node */
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return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
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}
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EXPORT_SYMBOL(of_n_addr_cells);
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int of_n_size_cells(struct device_node *np)
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{
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u32 cells;
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do {
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if (np->parent)
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np = np->parent;
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if (!of_property_read_u32(np, "#size-cells", &cells))
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return cells;
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} while (np->parent);
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/* No #size-cells property for the root node */
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return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
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}
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EXPORT_SYMBOL(of_n_size_cells);
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#ifdef CONFIG_NUMA
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int __weak of_node_to_nid(struct device_node *np)
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{
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return NUMA_NO_NODE;
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}
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#endif
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static struct device_node **phandle_cache;
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static u32 phandle_cache_mask;
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/*
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* Assumptions behind phandle_cache implementation:
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* - phandle property values are in a contiguous range of 1..n
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*
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* If the assumptions do not hold, then
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* - the phandle lookup overhead reduction provided by the cache
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* will likely be less
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*/
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static void of_populate_phandle_cache(void)
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{
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unsigned long flags;
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u32 cache_entries;
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struct device_node *np;
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u32 phandles = 0;
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raw_spin_lock_irqsave(&devtree_lock, flags);
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kfree(phandle_cache);
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phandle_cache = NULL;
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for_each_of_allnodes(np)
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if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL)
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phandles++;
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cache_entries = roundup_pow_of_two(phandles);
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phandle_cache_mask = cache_entries - 1;
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phandle_cache = kcalloc(cache_entries, sizeof(*phandle_cache),
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GFP_ATOMIC);
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if (!phandle_cache)
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goto out;
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for_each_of_allnodes(np)
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if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL)
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phandle_cache[np->phandle & phandle_cache_mask] = np;
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out:
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raw_spin_unlock_irqrestore(&devtree_lock, flags);
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}
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#ifndef CONFIG_MODULES
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static int __init of_free_phandle_cache(void)
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{
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unsigned long flags;
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raw_spin_lock_irqsave(&devtree_lock, flags);
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kfree(phandle_cache);
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phandle_cache = NULL;
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raw_spin_unlock_irqrestore(&devtree_lock, flags);
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return 0;
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}
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late_initcall_sync(of_free_phandle_cache);
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#endif
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void __init of_core_init(void)
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{
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struct device_node *np;
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of_populate_phandle_cache();
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/* Create the kset, and register existing nodes */
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mutex_lock(&of_mutex);
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of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
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if (!of_kset) {
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mutex_unlock(&of_mutex);
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pr_err("failed to register existing nodes\n");
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return;
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}
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for_each_of_allnodes(np)
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__of_attach_node_sysfs(np);
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mutex_unlock(&of_mutex);
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/* Symlink in /proc as required by userspace ABI */
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if (of_root)
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proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
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}
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static struct property *__of_find_property(const struct device_node *np,
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const char *name, int *lenp)
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{
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struct property *pp;
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if (!np)
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return NULL;
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for (pp = np->properties; pp; pp = pp->next) {
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if (of_prop_cmp(pp->name, name) == 0) {
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if (lenp)
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*lenp = pp->length;
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break;
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}
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}
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return pp;
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}
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struct property *of_find_property(const struct device_node *np,
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const char *name,
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int *lenp)
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{
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struct property *pp;
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unsigned long flags;
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raw_spin_lock_irqsave(&devtree_lock, flags);
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pp = __of_find_property(np, name, lenp);
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raw_spin_unlock_irqrestore(&devtree_lock, flags);
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return pp;
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}
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EXPORT_SYMBOL(of_find_property);
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struct device_node *__of_find_all_nodes(struct device_node *prev)
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{
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struct device_node *np;
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if (!prev) {
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np = of_root;
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} else if (prev->child) {
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np = prev->child;
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} else {
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/* Walk back up looking for a sibling, or the end of the structure */
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np = prev;
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while (np->parent && !np->sibling)
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np = np->parent;
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np = np->sibling; /* Might be null at the end of the tree */
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}
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return np;
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}
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/**
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* of_find_all_nodes - Get next node in global list
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* @prev: Previous node or NULL to start iteration
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* of_node_put() will be called on it
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*
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* Returns a node pointer with refcount incremented, use
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* of_node_put() on it when done.
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*/
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struct device_node *of_find_all_nodes(struct device_node *prev)
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{
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struct device_node *np;
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unsigned long flags;
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raw_spin_lock_irqsave(&devtree_lock, flags);
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np = __of_find_all_nodes(prev);
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of_node_get(np);
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of_node_put(prev);
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raw_spin_unlock_irqrestore(&devtree_lock, flags);
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return np;
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}
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EXPORT_SYMBOL(of_find_all_nodes);
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/*
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* Find a property with a given name for a given node
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* and return the value.
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*/
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const void *__of_get_property(const struct device_node *np,
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const char *name, int *lenp)
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{
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struct property *pp = __of_find_property(np, name, lenp);
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return pp ? pp->value : NULL;
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}
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/*
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* Find a property with a given name for a given node
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* and return the value.
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*/
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const void *of_get_property(const struct device_node *np, const char *name,
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int *lenp)
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{
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struct property *pp = of_find_property(np, name, lenp);
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return pp ? pp->value : NULL;
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}
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EXPORT_SYMBOL(of_get_property);
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/*
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* arch_match_cpu_phys_id - Match the given logical CPU and physical id
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*
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* @cpu: logical cpu index of a core/thread
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* @phys_id: physical identifier of a core/thread
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*
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* CPU logical to physical index mapping is architecture specific.
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* However this __weak function provides a default match of physical
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* id to logical cpu index. phys_id provided here is usually values read
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* from the device tree which must match the hardware internal registers.
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*
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* Returns true if the physical identifier and the logical cpu index
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* correspond to the same core/thread, false otherwise.
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*/
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bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id)
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{
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return (u32)phys_id == cpu;
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}
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/**
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* Checks if the given "prop_name" property holds the physical id of the
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* core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
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* NULL, local thread number within the core is returned in it.
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*/
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static bool __of_find_n_match_cpu_property(struct device_node *cpun,
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const char *prop_name, int cpu, unsigned int *thread)
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{
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const __be32 *cell;
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int ac, prop_len, tid;
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u64 hwid;
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ac = of_n_addr_cells(cpun);
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cell = of_get_property(cpun, prop_name, &prop_len);
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if (!cell || !ac)
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return false;
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prop_len /= sizeof(*cell) * ac;
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for (tid = 0; tid < prop_len; tid++) {
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hwid = of_read_number(cell, ac);
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if (arch_match_cpu_phys_id(cpu, hwid)) {
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if (thread)
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*thread = tid;
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return true;
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}
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cell += ac;
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}
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return false;
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}
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/*
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* arch_find_n_match_cpu_physical_id - See if the given device node is
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* for the cpu corresponding to logical cpu 'cpu'. Return true if so,
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* else false. If 'thread' is non-NULL, the local thread number within the
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* core is returned in it.
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*/
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bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun,
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int cpu, unsigned int *thread)
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{
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/* Check for non-standard "ibm,ppc-interrupt-server#s" property
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* for thread ids on PowerPC. If it doesn't exist fallback to
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* standard "reg" property.
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*/
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if (IS_ENABLED(CONFIG_PPC) &&
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__of_find_n_match_cpu_property(cpun,
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"ibm,ppc-interrupt-server#s",
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cpu, thread))
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return true;
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return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread);
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}
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/**
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* of_get_cpu_node - Get device node associated with the given logical CPU
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*
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* @cpu: CPU number(logical index) for which device node is required
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* @thread: if not NULL, local thread number within the physical core is
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* returned
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*
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* The main purpose of this function is to retrieve the device node for the
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* given logical CPU index. It should be used to initialize the of_node in
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* cpu device. Once of_node in cpu device is populated, all the further
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* references can use that instead.
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*
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* CPU logical to physical index mapping is architecture specific and is built
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* before booting secondary cores. This function uses arch_match_cpu_phys_id
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* which can be overridden by architecture specific implementation.
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*
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* Returns a node pointer for the logical cpu with refcount incremented, use
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* of_node_put() on it when done. Returns NULL if not found.
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*/
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struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
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{
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struct device_node *cpun;
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for_each_node_by_type(cpun, "cpu") {
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if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
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return cpun;
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}
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return NULL;
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}
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EXPORT_SYMBOL(of_get_cpu_node);
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/**
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* of_cpu_node_to_id: Get the logical CPU number for a given device_node
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*
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* @cpu_node: Pointer to the device_node for CPU.
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*
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* Returns the logical CPU number of the given CPU device_node.
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* Returns -ENODEV if the CPU is not found.
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*/
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int of_cpu_node_to_id(struct device_node *cpu_node)
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{
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int cpu;
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bool found = false;
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struct device_node *np;
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for_each_possible_cpu(cpu) {
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np = of_cpu_device_node_get(cpu);
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found = (cpu_node == np);
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of_node_put(np);
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if (found)
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return cpu;
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}
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return -ENODEV;
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}
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EXPORT_SYMBOL(of_cpu_node_to_id);
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/**
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* __of_device_is_compatible() - Check if the node matches given constraints
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* @device: pointer to node
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* @compat: required compatible string, NULL or "" for any match
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* @type: required device_type value, NULL or "" for any match
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* @name: required node name, NULL or "" for any match
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*
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* Checks if the given @compat, @type and @name strings match the
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* properties of the given @device. A constraints can be skipped by
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* passing NULL or an empty string as the constraint.
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*
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* Returns 0 for no match, and a positive integer on match. The return
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* value is a relative score with larger values indicating better
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* matches. The score is weighted for the most specific compatible value
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* to get the highest score. Matching type is next, followed by matching
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* name. Practically speaking, this results in the following priority
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* order for matches:
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*
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* 1. specific compatible && type && name
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* 2. specific compatible && type
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* 3. specific compatible && name
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* 4. specific compatible
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* 5. general compatible && type && name
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* 6. general compatible && type
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* 7. general compatible && name
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* 8. general compatible
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* 9. type && name
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* 10. type
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* 11. name
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*/
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static int __of_device_is_compatible(const struct device_node *device,
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const char *compat, const char *type, const char *name)
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{
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struct property *prop;
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const char *cp;
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int index = 0, score = 0;
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/* Compatible match has highest priority */
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if (compat && compat[0]) {
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prop = __of_find_property(device, "compatible", NULL);
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for (cp = of_prop_next_string(prop, NULL); cp;
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cp = of_prop_next_string(prop, cp), index++) {
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if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
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score = INT_MAX/2 - (index << 2);
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break;
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}
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}
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if (!score)
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return 0;
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}
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/* Matching type is better than matching name */
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if (type && type[0]) {
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if (!device->type || of_node_cmp(type, device->type))
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return 0;
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score += 2;
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}
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/* Matching name is a bit better than not */
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if (name && name[0]) {
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if (!device->name || of_node_cmp(name, device->name))
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return 0;
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score++;
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}
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return score;
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}
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/** Checks if the given "compat" string matches one of the strings in
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* the device's "compatible" property
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*/
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int of_device_is_compatible(const struct device_node *device,
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const char *compat)
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{
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unsigned long flags;
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int res;
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raw_spin_lock_irqsave(&devtree_lock, flags);
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res = __of_device_is_compatible(device, compat, NULL, NULL);
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raw_spin_unlock_irqrestore(&devtree_lock, flags);
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return res;
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}
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EXPORT_SYMBOL(of_device_is_compatible);
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/** Checks if the device is compatible with any of the entries in
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* a NULL terminated array of strings. Returns the best match
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* score or 0.
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*/
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int of_device_compatible_match(struct device_node *device,
|
|
const char *const *compat)
|
|
{
|
|
unsigned int tmp, score = 0;
|
|
|
|
if (!compat)
|
|
return 0;
|
|
|
|
while (*compat) {
|
|
tmp = of_device_is_compatible(device, *compat);
|
|
if (tmp > score)
|
|
score = tmp;
|
|
compat++;
|
|
}
|
|
|
|
return score;
|
|
}
|
|
|
|
/**
|
|
* of_machine_is_compatible - Test root of device tree for a given compatible value
|
|
* @compat: compatible string to look for in root node's compatible property.
|
|
*
|
|
* Returns a positive integer if the root node has the given value in its
|
|
* compatible property.
|
|
*/
|
|
int of_machine_is_compatible(const char *compat)
|
|
{
|
|
struct device_node *root;
|
|
int rc = 0;
|
|
|
|
root = of_find_node_by_path("/");
|
|
if (root) {
|
|
rc = of_device_is_compatible(root, compat);
|
|
of_node_put(root);
|
|
}
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL(of_machine_is_compatible);
|
|
|
|
/**
|
|
* __of_device_is_available - check if a device is available for use
|
|
*
|
|
* @device: Node to check for availability, with locks already held
|
|
*
|
|
* Returns true if the status property is absent or set to "okay" or "ok",
|
|
* false otherwise
|
|
*/
|
|
static bool __of_device_is_available(const struct device_node *device)
|
|
{
|
|
const char *status;
|
|
int statlen;
|
|
|
|
if (!device)
|
|
return false;
|
|
|
|
status = __of_get_property(device, "status", &statlen);
|
|
if (status == NULL)
|
|
return true;
|
|
|
|
if (statlen > 0) {
|
|
if (!strcmp(status, "okay") || !strcmp(status, "ok"))
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* of_device_is_available - check if a device is available for use
|
|
*
|
|
* @device: Node to check for availability
|
|
*
|
|
* Returns true if the status property is absent or set to "okay" or "ok",
|
|
* false otherwise
|
|
*/
|
|
bool of_device_is_available(const struct device_node *device)
|
|
{
|
|
unsigned long flags;
|
|
bool res;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
res = __of_device_is_available(device);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return res;
|
|
|
|
}
|
|
EXPORT_SYMBOL(of_device_is_available);
|
|
|
|
/**
|
|
* of_device_is_big_endian - check if a device has BE registers
|
|
*
|
|
* @device: Node to check for endianness
|
|
*
|
|
* Returns true if the device has a "big-endian" property, or if the kernel
|
|
* was compiled for BE *and* the device has a "native-endian" property.
|
|
* Returns false otherwise.
|
|
*
|
|
* Callers would nominally use ioread32be/iowrite32be if
|
|
* of_device_is_big_endian() == true, or readl/writel otherwise.
|
|
*/
|
|
bool of_device_is_big_endian(const struct device_node *device)
|
|
{
|
|
if (of_property_read_bool(device, "big-endian"))
|
|
return true;
|
|
if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
|
|
of_property_read_bool(device, "native-endian"))
|
|
return true;
|
|
return false;
|
|
}
|
|
EXPORT_SYMBOL(of_device_is_big_endian);
|
|
|
|
/**
|
|
* of_get_parent - Get a node's parent if any
|
|
* @node: Node to get parent
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_get_parent(const struct device_node *node)
|
|
{
|
|
struct device_node *np;
|
|
unsigned long flags;
|
|
|
|
if (!node)
|
|
return NULL;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
np = of_node_get(node->parent);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_get_parent);
|
|
|
|
/**
|
|
* of_get_next_parent - Iterate to a node's parent
|
|
* @node: Node to get parent of
|
|
*
|
|
* This is like of_get_parent() except that it drops the
|
|
* refcount on the passed node, making it suitable for iterating
|
|
* through a node's parents.
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_get_next_parent(struct device_node *node)
|
|
{
|
|
struct device_node *parent;
|
|
unsigned long flags;
|
|
|
|
if (!node)
|
|
return NULL;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
parent = of_node_get(node->parent);
|
|
of_node_put(node);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return parent;
|
|
}
|
|
EXPORT_SYMBOL(of_get_next_parent);
|
|
|
|
static struct device_node *__of_get_next_child(const struct device_node *node,
|
|
struct device_node *prev)
|
|
{
|
|
struct device_node *next;
|
|
|
|
if (!node)
|
|
return NULL;
|
|
|
|
next = prev ? prev->sibling : node->child;
|
|
for (; next; next = next->sibling)
|
|
if (of_node_get(next))
|
|
break;
|
|
of_node_put(prev);
|
|
return next;
|
|
}
|
|
#define __for_each_child_of_node(parent, child) \
|
|
for (child = __of_get_next_child(parent, NULL); child != NULL; \
|
|
child = __of_get_next_child(parent, child))
|
|
|
|
/**
|
|
* of_get_next_child - Iterate a node childs
|
|
* @node: parent node
|
|
* @prev: previous child of the parent node, or NULL to get first
|
|
*
|
|
* Returns a node pointer with refcount incremented, use of_node_put() on
|
|
* it when done. Returns NULL when prev is the last child. Decrements the
|
|
* refcount of prev.
|
|
*/
|
|
struct device_node *of_get_next_child(const struct device_node *node,
|
|
struct device_node *prev)
|
|
{
|
|
struct device_node *next;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
next = __of_get_next_child(node, prev);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return next;
|
|
}
|
|
EXPORT_SYMBOL(of_get_next_child);
|
|
|
|
/**
|
|
* of_get_next_available_child - Find the next available child node
|
|
* @node: parent node
|
|
* @prev: previous child of the parent node, or NULL to get first
|
|
*
|
|
* This function is like of_get_next_child(), except that it
|
|
* automatically skips any disabled nodes (i.e. status = "disabled").
|
|
*/
|
|
struct device_node *of_get_next_available_child(const struct device_node *node,
|
|
struct device_node *prev)
|
|
{
|
|
struct device_node *next;
|
|
unsigned long flags;
|
|
|
|
if (!node)
|
|
return NULL;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
next = prev ? prev->sibling : node->child;
|
|
for (; next; next = next->sibling) {
|
|
if (!__of_device_is_available(next))
|
|
continue;
|
|
if (of_node_get(next))
|
|
break;
|
|
}
|
|
of_node_put(prev);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return next;
|
|
}
|
|
EXPORT_SYMBOL(of_get_next_available_child);
|
|
|
|
/**
|
|
* of_get_child_by_name - Find the child node by name for a given parent
|
|
* @node: parent node
|
|
* @name: child name to look for.
|
|
*
|
|
* This function looks for child node for given matching name
|
|
*
|
|
* Returns a node pointer if found, with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
* Returns NULL if node is not found.
|
|
*/
|
|
struct device_node *of_get_child_by_name(const struct device_node *node,
|
|
const char *name)
|
|
{
|
|
struct device_node *child;
|
|
|
|
for_each_child_of_node(node, child)
|
|
if (child->name && (of_node_cmp(child->name, name) == 0))
|
|
break;
|
|
return child;
|
|
}
|
|
EXPORT_SYMBOL(of_get_child_by_name);
|
|
|
|
struct device_node *__of_find_node_by_path(struct device_node *parent,
|
|
const char *path)
|
|
{
|
|
struct device_node *child;
|
|
int len;
|
|
|
|
len = strcspn(path, "/:");
|
|
if (!len)
|
|
return NULL;
|
|
|
|
__for_each_child_of_node(parent, child) {
|
|
const char *name = kbasename(child->full_name);
|
|
if (strncmp(path, name, len) == 0 && (strlen(name) == len))
|
|
return child;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
struct device_node *__of_find_node_by_full_path(struct device_node *node,
|
|
const char *path)
|
|
{
|
|
const char *separator = strchr(path, ':');
|
|
|
|
while (node && *path == '/') {
|
|
struct device_node *tmp = node;
|
|
|
|
path++; /* Increment past '/' delimiter */
|
|
node = __of_find_node_by_path(node, path);
|
|
of_node_put(tmp);
|
|
path = strchrnul(path, '/');
|
|
if (separator && separator < path)
|
|
break;
|
|
}
|
|
return node;
|
|
}
|
|
|
|
/**
|
|
* of_find_node_opts_by_path - Find a node matching a full OF path
|
|
* @path: Either the full path to match, or if the path does not
|
|
* start with '/', the name of a property of the /aliases
|
|
* node (an alias). In the case of an alias, the node
|
|
* matching the alias' value will be returned.
|
|
* @opts: Address of a pointer into which to store the start of
|
|
* an options string appended to the end of the path with
|
|
* a ':' separator.
|
|
*
|
|
* Valid paths:
|
|
* /foo/bar Full path
|
|
* foo Valid alias
|
|
* foo/bar Valid alias + relative path
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_node_opts_by_path(const char *path, const char **opts)
|
|
{
|
|
struct device_node *np = NULL;
|
|
struct property *pp;
|
|
unsigned long flags;
|
|
const char *separator = strchr(path, ':');
|
|
|
|
if (opts)
|
|
*opts = separator ? separator + 1 : NULL;
|
|
|
|
if (strcmp(path, "/") == 0)
|
|
return of_node_get(of_root);
|
|
|
|
/* The path could begin with an alias */
|
|
if (*path != '/') {
|
|
int len;
|
|
const char *p = separator;
|
|
|
|
if (!p)
|
|
p = strchrnul(path, '/');
|
|
len = p - path;
|
|
|
|
/* of_aliases must not be NULL */
|
|
if (!of_aliases)
|
|
return NULL;
|
|
|
|
for_each_property_of_node(of_aliases, pp) {
|
|
if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
|
|
np = of_find_node_by_path(pp->value);
|
|
break;
|
|
}
|
|
}
|
|
if (!np)
|
|
return NULL;
|
|
path = p;
|
|
}
|
|
|
|
/* Step down the tree matching path components */
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
if (!np)
|
|
np = of_node_get(of_root);
|
|
np = __of_find_node_by_full_path(np, path);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_node_opts_by_path);
|
|
|
|
/**
|
|
* of_find_node_by_name - Find a node by its "name" property
|
|
* @from: The node to start searching from or NULL; the node
|
|
* you pass will not be searched, only the next one
|
|
* will. Typically, you pass what the previous call
|
|
* returned. of_node_put() will be called on @from.
|
|
* @name: The name string to match against
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_node_by_name(struct device_node *from,
|
|
const char *name)
|
|
{
|
|
struct device_node *np;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
for_each_of_allnodes_from(from, np)
|
|
if (np->name && (of_node_cmp(np->name, name) == 0)
|
|
&& of_node_get(np))
|
|
break;
|
|
of_node_put(from);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_node_by_name);
|
|
|
|
/**
|
|
* of_find_node_by_type - Find a node by its "device_type" property
|
|
* @from: The node to start searching from, or NULL to start searching
|
|
* the entire device tree. The node you pass will not be
|
|
* searched, only the next one will; typically, you pass
|
|
* what the previous call returned. of_node_put() will be
|
|
* called on from for you.
|
|
* @type: The type string to match against
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_node_by_type(struct device_node *from,
|
|
const char *type)
|
|
{
|
|
struct device_node *np;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
for_each_of_allnodes_from(from, np)
|
|
if (np->type && (of_node_cmp(np->type, type) == 0)
|
|
&& of_node_get(np))
|
|
break;
|
|
of_node_put(from);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_node_by_type);
|
|
|
|
/**
|
|
* of_find_compatible_node - Find a node based on type and one of the
|
|
* tokens in its "compatible" property
|
|
* @from: The node to start searching from or NULL, the node
|
|
* you pass will not be searched, only the next one
|
|
* will; typically, you pass what the previous call
|
|
* returned. of_node_put() will be called on it
|
|
* @type: The type string to match "device_type" or NULL to ignore
|
|
* @compatible: The string to match to one of the tokens in the device
|
|
* "compatible" list.
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_compatible_node(struct device_node *from,
|
|
const char *type, const char *compatible)
|
|
{
|
|
struct device_node *np;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
for_each_of_allnodes_from(from, np)
|
|
if (__of_device_is_compatible(np, compatible, type, NULL) &&
|
|
of_node_get(np))
|
|
break;
|
|
of_node_put(from);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_compatible_node);
|
|
|
|
/**
|
|
* of_find_node_with_property - Find a node which has a property with
|
|
* the given name.
|
|
* @from: The node to start searching from or NULL, the node
|
|
* you pass will not be searched, only the next one
|
|
* will; typically, you pass what the previous call
|
|
* returned. of_node_put() will be called on it
|
|
* @prop_name: The name of the property to look for.
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_node_with_property(struct device_node *from,
|
|
const char *prop_name)
|
|
{
|
|
struct device_node *np;
|
|
struct property *pp;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
for_each_of_allnodes_from(from, np) {
|
|
for (pp = np->properties; pp; pp = pp->next) {
|
|
if (of_prop_cmp(pp->name, prop_name) == 0) {
|
|
of_node_get(np);
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
out:
|
|
of_node_put(from);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_node_with_property);
|
|
|
|
static
|
|
const struct of_device_id *__of_match_node(const struct of_device_id *matches,
|
|
const struct device_node *node)
|
|
{
|
|
const struct of_device_id *best_match = NULL;
|
|
int score, best_score = 0;
|
|
|
|
if (!matches)
|
|
return NULL;
|
|
|
|
for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) {
|
|
score = __of_device_is_compatible(node, matches->compatible,
|
|
matches->type, matches->name);
|
|
if (score > best_score) {
|
|
best_match = matches;
|
|
best_score = score;
|
|
}
|
|
}
|
|
|
|
return best_match;
|
|
}
|
|
|
|
/**
|
|
* of_match_node - Tell if a device_node has a matching of_match structure
|
|
* @matches: array of of device match structures to search in
|
|
* @node: the of device structure to match against
|
|
*
|
|
* Low level utility function used by device matching.
|
|
*/
|
|
const struct of_device_id *of_match_node(const struct of_device_id *matches,
|
|
const struct device_node *node)
|
|
{
|
|
const struct of_device_id *match;
|
|
unsigned long flags;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
match = __of_match_node(matches, node);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return match;
|
|
}
|
|
EXPORT_SYMBOL(of_match_node);
|
|
|
|
/**
|
|
* of_find_matching_node_and_match - Find a node based on an of_device_id
|
|
* match table.
|
|
* @from: The node to start searching from or NULL, the node
|
|
* you pass will not be searched, only the next one
|
|
* will; typically, you pass what the previous call
|
|
* returned. of_node_put() will be called on it
|
|
* @matches: array of of device match structures to search in
|
|
* @match Updated to point at the matches entry which matched
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_matching_node_and_match(struct device_node *from,
|
|
const struct of_device_id *matches,
|
|
const struct of_device_id **match)
|
|
{
|
|
struct device_node *np;
|
|
const struct of_device_id *m;
|
|
unsigned long flags;
|
|
|
|
if (match)
|
|
*match = NULL;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
for_each_of_allnodes_from(from, np) {
|
|
m = __of_match_node(matches, np);
|
|
if (m && of_node_get(np)) {
|
|
if (match)
|
|
*match = m;
|
|
break;
|
|
}
|
|
}
|
|
of_node_put(from);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_matching_node_and_match);
|
|
|
|
/**
|
|
* of_modalias_node - Lookup appropriate modalias for a device node
|
|
* @node: pointer to a device tree node
|
|
* @modalias: Pointer to buffer that modalias value will be copied into
|
|
* @len: Length of modalias value
|
|
*
|
|
* Based on the value of the compatible property, this routine will attempt
|
|
* to choose an appropriate modalias value for a particular device tree node.
|
|
* It does this by stripping the manufacturer prefix (as delimited by a ',')
|
|
* from the first entry in the compatible list property.
|
|
*
|
|
* This routine returns 0 on success, <0 on failure.
|
|
*/
|
|
int of_modalias_node(struct device_node *node, char *modalias, int len)
|
|
{
|
|
const char *compatible, *p;
|
|
int cplen;
|
|
|
|
compatible = of_get_property(node, "compatible", &cplen);
|
|
if (!compatible || strlen(compatible) > cplen)
|
|
return -ENODEV;
|
|
p = strchr(compatible, ',');
|
|
strlcpy(modalias, p ? p + 1 : compatible, len);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_modalias_node);
|
|
|
|
/**
|
|
* of_find_node_by_phandle - Find a node given a phandle
|
|
* @handle: phandle of the node to find
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_find_node_by_phandle(phandle handle)
|
|
{
|
|
struct device_node *np = NULL;
|
|
unsigned long flags;
|
|
phandle masked_handle;
|
|
|
|
if (!handle)
|
|
return NULL;
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
|
|
masked_handle = handle & phandle_cache_mask;
|
|
|
|
if (phandle_cache) {
|
|
if (phandle_cache[masked_handle] &&
|
|
handle == phandle_cache[masked_handle]->phandle)
|
|
np = phandle_cache[masked_handle];
|
|
}
|
|
|
|
if (!np) {
|
|
for_each_of_allnodes(np)
|
|
if (np->phandle == handle) {
|
|
if (phandle_cache)
|
|
phandle_cache[masked_handle] = np;
|
|
break;
|
|
}
|
|
}
|
|
|
|
of_node_get(np);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
return np;
|
|
}
|
|
EXPORT_SYMBOL(of_find_node_by_phandle);
|
|
|
|
void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
|
|
{
|
|
int i;
|
|
printk("%s %pOF", msg, args->np);
|
|
for (i = 0; i < args->args_count; i++) {
|
|
const char delim = i ? ',' : ':';
|
|
|
|
pr_cont("%c%08x", delim, args->args[i]);
|
|
}
|
|
pr_cont("\n");
|
|
}
|
|
|
|
int of_phandle_iterator_init(struct of_phandle_iterator *it,
|
|
const struct device_node *np,
|
|
const char *list_name,
|
|
const char *cells_name,
|
|
int cell_count)
|
|
{
|
|
const __be32 *list;
|
|
int size;
|
|
|
|
memset(it, 0, sizeof(*it));
|
|
|
|
list = of_get_property(np, list_name, &size);
|
|
if (!list)
|
|
return -ENOENT;
|
|
|
|
it->cells_name = cells_name;
|
|
it->cell_count = cell_count;
|
|
it->parent = np;
|
|
it->list_end = list + size / sizeof(*list);
|
|
it->phandle_end = list;
|
|
it->cur = list;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_phandle_iterator_init);
|
|
|
|
int of_phandle_iterator_next(struct of_phandle_iterator *it)
|
|
{
|
|
uint32_t count = 0;
|
|
|
|
if (it->node) {
|
|
of_node_put(it->node);
|
|
it->node = NULL;
|
|
}
|
|
|
|
if (!it->cur || it->phandle_end >= it->list_end)
|
|
return -ENOENT;
|
|
|
|
it->cur = it->phandle_end;
|
|
|
|
/* If phandle is 0, then it is an empty entry with no arguments. */
|
|
it->phandle = be32_to_cpup(it->cur++);
|
|
|
|
if (it->phandle) {
|
|
|
|
/*
|
|
* Find the provider node and parse the #*-cells property to
|
|
* determine the argument length.
|
|
*/
|
|
it->node = of_find_node_by_phandle(it->phandle);
|
|
|
|
if (it->cells_name) {
|
|
if (!it->node) {
|
|
pr_err("%pOF: could not find phandle\n",
|
|
it->parent);
|
|
goto err;
|
|
}
|
|
|
|
if (of_property_read_u32(it->node, it->cells_name,
|
|
&count)) {
|
|
pr_err("%pOF: could not get %s for %pOF\n",
|
|
it->parent,
|
|
it->cells_name,
|
|
it->node);
|
|
goto err;
|
|
}
|
|
} else {
|
|
count = it->cell_count;
|
|
}
|
|
|
|
/*
|
|
* Make sure that the arguments actually fit in the remaining
|
|
* property data length
|
|
*/
|
|
if (it->cur + count > it->list_end) {
|
|
pr_err("%pOF: arguments longer than property\n",
|
|
it->parent);
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
it->phandle_end = it->cur + count;
|
|
it->cur_count = count;
|
|
|
|
return 0;
|
|
|
|
err:
|
|
if (it->node) {
|
|
of_node_put(it->node);
|
|
it->node = NULL;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_phandle_iterator_next);
|
|
|
|
int of_phandle_iterator_args(struct of_phandle_iterator *it,
|
|
uint32_t *args,
|
|
int size)
|
|
{
|
|
int i, count;
|
|
|
|
count = it->cur_count;
|
|
|
|
if (WARN_ON(size < count))
|
|
count = size;
|
|
|
|
for (i = 0; i < count; i++)
|
|
args[i] = be32_to_cpup(it->cur++);
|
|
|
|
return count;
|
|
}
|
|
|
|
static int __of_parse_phandle_with_args(const struct device_node *np,
|
|
const char *list_name,
|
|
const char *cells_name,
|
|
int cell_count, int index,
|
|
struct of_phandle_args *out_args)
|
|
{
|
|
struct of_phandle_iterator it;
|
|
int rc, cur_index = 0;
|
|
|
|
/* Loop over the phandles until all the requested entry is found */
|
|
of_for_each_phandle(&it, rc, np, list_name, cells_name, cell_count) {
|
|
/*
|
|
* All of the error cases bail out of the loop, so at
|
|
* this point, the parsing is successful. If the requested
|
|
* index matches, then fill the out_args structure and return,
|
|
* or return -ENOENT for an empty entry.
|
|
*/
|
|
rc = -ENOENT;
|
|
if (cur_index == index) {
|
|
if (!it.phandle)
|
|
goto err;
|
|
|
|
if (out_args) {
|
|
int c;
|
|
|
|
c = of_phandle_iterator_args(&it,
|
|
out_args->args,
|
|
MAX_PHANDLE_ARGS);
|
|
out_args->np = it.node;
|
|
out_args->args_count = c;
|
|
} else {
|
|
of_node_put(it.node);
|
|
}
|
|
|
|
/* Found it! return success */
|
|
return 0;
|
|
}
|
|
|
|
cur_index++;
|
|
}
|
|
|
|
/*
|
|
* Unlock node before returning result; will be one of:
|
|
* -ENOENT : index is for empty phandle
|
|
* -EINVAL : parsing error on data
|
|
*/
|
|
|
|
err:
|
|
of_node_put(it.node);
|
|
return rc;
|
|
}
|
|
|
|
/**
|
|
* of_parse_phandle - Resolve a phandle property to a device_node pointer
|
|
* @np: Pointer to device node holding phandle property
|
|
* @phandle_name: Name of property holding a phandle value
|
|
* @index: For properties holding a table of phandles, this is the index into
|
|
* the table
|
|
*
|
|
* Returns the device_node pointer with refcount incremented. Use
|
|
* of_node_put() on it when done.
|
|
*/
|
|
struct device_node *of_parse_phandle(const struct device_node *np,
|
|
const char *phandle_name, int index)
|
|
{
|
|
struct of_phandle_args args;
|
|
|
|
if (index < 0)
|
|
return NULL;
|
|
|
|
if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
|
|
index, &args))
|
|
return NULL;
|
|
|
|
return args.np;
|
|
}
|
|
EXPORT_SYMBOL(of_parse_phandle);
|
|
|
|
/**
|
|
* of_parse_phandle_with_args() - Find a node pointed by phandle in a list
|
|
* @np: pointer to a device tree node containing a list
|
|
* @list_name: property name that contains a list
|
|
* @cells_name: property name that specifies phandles' arguments count
|
|
* @index: index of a phandle to parse out
|
|
* @out_args: optional pointer to output arguments structure (will be filled)
|
|
*
|
|
* This function is useful to parse lists of phandles and their arguments.
|
|
* Returns 0 on success and fills out_args, on error returns appropriate
|
|
* errno value.
|
|
*
|
|
* Caller is responsible to call of_node_put() on the returned out_args->np
|
|
* pointer.
|
|
*
|
|
* Example:
|
|
*
|
|
* phandle1: node1 {
|
|
* #list-cells = <2>;
|
|
* }
|
|
*
|
|
* phandle2: node2 {
|
|
* #list-cells = <1>;
|
|
* }
|
|
*
|
|
* node3 {
|
|
* list = <&phandle1 1 2 &phandle2 3>;
|
|
* }
|
|
*
|
|
* To get a device_node of the `node2' node you may call this:
|
|
* of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
|
|
*/
|
|
int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
|
|
const char *cells_name, int index,
|
|
struct of_phandle_args *out_args)
|
|
{
|
|
if (index < 0)
|
|
return -EINVAL;
|
|
return __of_parse_phandle_with_args(np, list_name, cells_name, 0,
|
|
index, out_args);
|
|
}
|
|
EXPORT_SYMBOL(of_parse_phandle_with_args);
|
|
|
|
/**
|
|
* of_parse_phandle_with_args_map() - Find a node pointed by phandle in a list and remap it
|
|
* @np: pointer to a device tree node containing a list
|
|
* @list_name: property name that contains a list
|
|
* @stem_name: stem of property names that specify phandles' arguments count
|
|
* @index: index of a phandle to parse out
|
|
* @out_args: optional pointer to output arguments structure (will be filled)
|
|
*
|
|
* This function is useful to parse lists of phandles and their arguments.
|
|
* Returns 0 on success and fills out_args, on error returns appropriate errno
|
|
* value. The difference between this function and of_parse_phandle_with_args()
|
|
* is that this API remaps a phandle if the node the phandle points to has
|
|
* a <@stem_name>-map property.
|
|
*
|
|
* Caller is responsible to call of_node_put() on the returned out_args->np
|
|
* pointer.
|
|
*
|
|
* Example:
|
|
*
|
|
* phandle1: node1 {
|
|
* #list-cells = <2>;
|
|
* }
|
|
*
|
|
* phandle2: node2 {
|
|
* #list-cells = <1>;
|
|
* }
|
|
*
|
|
* phandle3: node3 {
|
|
* #list-cells = <1>;
|
|
* list-map = <0 &phandle2 3>,
|
|
* <1 &phandle2 2>,
|
|
* <2 &phandle1 5 1>;
|
|
* list-map-mask = <0x3>;
|
|
* };
|
|
*
|
|
* node4 {
|
|
* list = <&phandle1 1 2 &phandle3 0>;
|
|
* }
|
|
*
|
|
* To get a device_node of the `node2' node you may call this:
|
|
* of_parse_phandle_with_args(node4, "list", "list", 1, &args);
|
|
*/
|
|
int of_parse_phandle_with_args_map(const struct device_node *np,
|
|
const char *list_name,
|
|
const char *stem_name,
|
|
int index, struct of_phandle_args *out_args)
|
|
{
|
|
char *cells_name, *map_name = NULL, *mask_name = NULL;
|
|
char *pass_name = NULL;
|
|
struct device_node *cur, *new = NULL;
|
|
const __be32 *map, *mask, *pass;
|
|
static const __be32 dummy_mask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
|
|
static const __be32 dummy_pass[] = { [0 ... MAX_PHANDLE_ARGS] = 0 };
|
|
__be32 initial_match_array[MAX_PHANDLE_ARGS];
|
|
const __be32 *match_array = initial_match_array;
|
|
int i, ret, map_len, match;
|
|
u32 list_size, new_size;
|
|
|
|
if (index < 0)
|
|
return -EINVAL;
|
|
|
|
cells_name = kasprintf(GFP_KERNEL, "#%s-cells", stem_name);
|
|
if (!cells_name)
|
|
return -ENOMEM;
|
|
|
|
ret = -ENOMEM;
|
|
map_name = kasprintf(GFP_KERNEL, "%s-map", stem_name);
|
|
if (!map_name)
|
|
goto free;
|
|
|
|
mask_name = kasprintf(GFP_KERNEL, "%s-map-mask", stem_name);
|
|
if (!mask_name)
|
|
goto free;
|
|
|
|
pass_name = kasprintf(GFP_KERNEL, "%s-map-pass-thru", stem_name);
|
|
if (!pass_name)
|
|
goto free;
|
|
|
|
ret = __of_parse_phandle_with_args(np, list_name, cells_name, 0, index,
|
|
out_args);
|
|
if (ret)
|
|
goto free;
|
|
|
|
/* Get the #<list>-cells property */
|
|
cur = out_args->np;
|
|
ret = of_property_read_u32(cur, cells_name, &list_size);
|
|
if (ret < 0)
|
|
goto put;
|
|
|
|
/* Precalculate the match array - this simplifies match loop */
|
|
for (i = 0; i < list_size; i++)
|
|
initial_match_array[i] = cpu_to_be32(out_args->args[i]);
|
|
|
|
ret = -EINVAL;
|
|
while (cur) {
|
|
/* Get the <list>-map property */
|
|
map = of_get_property(cur, map_name, &map_len);
|
|
if (!map) {
|
|
ret = 0;
|
|
goto free;
|
|
}
|
|
map_len /= sizeof(u32);
|
|
|
|
/* Get the <list>-map-mask property (optional) */
|
|
mask = of_get_property(cur, mask_name, NULL);
|
|
if (!mask)
|
|
mask = dummy_mask;
|
|
/* Iterate through <list>-map property */
|
|
match = 0;
|
|
while (map_len > (list_size + 1) && !match) {
|
|
/* Compare specifiers */
|
|
match = 1;
|
|
for (i = 0; i < list_size; i++, map_len--)
|
|
match &= !((match_array[i] ^ *map++) & mask[i]);
|
|
|
|
of_node_put(new);
|
|
new = of_find_node_by_phandle(be32_to_cpup(map));
|
|
map++;
|
|
map_len--;
|
|
|
|
/* Check if not found */
|
|
if (!new)
|
|
goto put;
|
|
|
|
if (!of_device_is_available(new))
|
|
match = 0;
|
|
|
|
ret = of_property_read_u32(new, cells_name, &new_size);
|
|
if (ret)
|
|
goto put;
|
|
|
|
/* Check for malformed properties */
|
|
if (WARN_ON(new_size > MAX_PHANDLE_ARGS))
|
|
goto put;
|
|
if (map_len < new_size)
|
|
goto put;
|
|
|
|
/* Move forward by new node's #<list>-cells amount */
|
|
map += new_size;
|
|
map_len -= new_size;
|
|
}
|
|
if (!match)
|
|
goto put;
|
|
|
|
/* Get the <list>-map-pass-thru property (optional) */
|
|
pass = of_get_property(cur, pass_name, NULL);
|
|
if (!pass)
|
|
pass = dummy_pass;
|
|
|
|
/*
|
|
* Successfully parsed a <list>-map translation; copy new
|
|
* specifier into the out_args structure, keeping the
|
|
* bits specified in <list>-map-pass-thru.
|
|
*/
|
|
match_array = map - new_size;
|
|
for (i = 0; i < new_size; i++) {
|
|
__be32 val = *(map - new_size + i);
|
|
|
|
if (i < list_size) {
|
|
val &= ~pass[i];
|
|
val |= cpu_to_be32(out_args->args[i]) & pass[i];
|
|
}
|
|
|
|
out_args->args[i] = be32_to_cpu(val);
|
|
}
|
|
out_args->args_count = list_size = new_size;
|
|
/* Iterate again with new provider */
|
|
out_args->np = new;
|
|
of_node_put(cur);
|
|
cur = new;
|
|
}
|
|
put:
|
|
of_node_put(cur);
|
|
of_node_put(new);
|
|
free:
|
|
kfree(mask_name);
|
|
kfree(map_name);
|
|
kfree(cells_name);
|
|
kfree(pass_name);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(of_parse_phandle_with_args_map);
|
|
|
|
/**
|
|
* of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
|
|
* @np: pointer to a device tree node containing a list
|
|
* @list_name: property name that contains a list
|
|
* @cell_count: number of argument cells following the phandle
|
|
* @index: index of a phandle to parse out
|
|
* @out_args: optional pointer to output arguments structure (will be filled)
|
|
*
|
|
* This function is useful to parse lists of phandles and their arguments.
|
|
* Returns 0 on success and fills out_args, on error returns appropriate
|
|
* errno value.
|
|
*
|
|
* Caller is responsible to call of_node_put() on the returned out_args->np
|
|
* pointer.
|
|
*
|
|
* Example:
|
|
*
|
|
* phandle1: node1 {
|
|
* }
|
|
*
|
|
* phandle2: node2 {
|
|
* }
|
|
*
|
|
* node3 {
|
|
* list = <&phandle1 0 2 &phandle2 2 3>;
|
|
* }
|
|
*
|
|
* To get a device_node of the `node2' node you may call this:
|
|
* of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
|
|
*/
|
|
int of_parse_phandle_with_fixed_args(const struct device_node *np,
|
|
const char *list_name, int cell_count,
|
|
int index, struct of_phandle_args *out_args)
|
|
{
|
|
if (index < 0)
|
|
return -EINVAL;
|
|
return __of_parse_phandle_with_args(np, list_name, NULL, cell_count,
|
|
index, out_args);
|
|
}
|
|
EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
|
|
|
|
/**
|
|
* of_count_phandle_with_args() - Find the number of phandles references in a property
|
|
* @np: pointer to a device tree node containing a list
|
|
* @list_name: property name that contains a list
|
|
* @cells_name: property name that specifies phandles' arguments count
|
|
*
|
|
* Returns the number of phandle + argument tuples within a property. It
|
|
* is a typical pattern to encode a list of phandle and variable
|
|
* arguments into a single property. The number of arguments is encoded
|
|
* by a property in the phandle-target node. For example, a gpios
|
|
* property would contain a list of GPIO specifies consisting of a
|
|
* phandle and 1 or more arguments. The number of arguments are
|
|
* determined by the #gpio-cells property in the node pointed to by the
|
|
* phandle.
|
|
*/
|
|
int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
|
|
const char *cells_name)
|
|
{
|
|
struct of_phandle_iterator it;
|
|
int rc, cur_index = 0;
|
|
|
|
rc = of_phandle_iterator_init(&it, np, list_name, cells_name, 0);
|
|
if (rc)
|
|
return rc;
|
|
|
|
while ((rc = of_phandle_iterator_next(&it)) == 0)
|
|
cur_index += 1;
|
|
|
|
if (rc != -ENOENT)
|
|
return rc;
|
|
|
|
return cur_index;
|
|
}
|
|
EXPORT_SYMBOL(of_count_phandle_with_args);
|
|
|
|
/**
|
|
* __of_add_property - Add a property to a node without lock operations
|
|
*/
|
|
int __of_add_property(struct device_node *np, struct property *prop)
|
|
{
|
|
struct property **next;
|
|
|
|
prop->next = NULL;
|
|
next = &np->properties;
|
|
while (*next) {
|
|
if (strcmp(prop->name, (*next)->name) == 0)
|
|
/* duplicate ! don't insert it */
|
|
return -EEXIST;
|
|
|
|
next = &(*next)->next;
|
|
}
|
|
*next = prop;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* of_add_property - Add a property to a node
|
|
*/
|
|
int of_add_property(struct device_node *np, struct property *prop)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
mutex_lock(&of_mutex);
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
rc = __of_add_property(np, prop);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
|
|
if (!rc)
|
|
__of_add_property_sysfs(np, prop);
|
|
|
|
mutex_unlock(&of_mutex);
|
|
|
|
if (!rc)
|
|
of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int __of_remove_property(struct device_node *np, struct property *prop)
|
|
{
|
|
struct property **next;
|
|
|
|
for (next = &np->properties; *next; next = &(*next)->next) {
|
|
if (*next == prop)
|
|
break;
|
|
}
|
|
if (*next == NULL)
|
|
return -ENODEV;
|
|
|
|
/* found the node */
|
|
*next = prop->next;
|
|
prop->next = np->deadprops;
|
|
np->deadprops = prop;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* of_remove_property - Remove a property from a node.
|
|
*
|
|
* Note that we don't actually remove it, since we have given out
|
|
* who-knows-how-many pointers to the data using get-property.
|
|
* Instead we just move the property to the "dead properties"
|
|
* list, so it won't be found any more.
|
|
*/
|
|
int of_remove_property(struct device_node *np, struct property *prop)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
if (!prop)
|
|
return -ENODEV;
|
|
|
|
mutex_lock(&of_mutex);
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
rc = __of_remove_property(np, prop);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
|
|
if (!rc)
|
|
__of_remove_property_sysfs(np, prop);
|
|
|
|
mutex_unlock(&of_mutex);
|
|
|
|
if (!rc)
|
|
of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int __of_update_property(struct device_node *np, struct property *newprop,
|
|
struct property **oldpropp)
|
|
{
|
|
struct property **next, *oldprop;
|
|
|
|
for (next = &np->properties; *next; next = &(*next)->next) {
|
|
if (of_prop_cmp((*next)->name, newprop->name) == 0)
|
|
break;
|
|
}
|
|
*oldpropp = oldprop = *next;
|
|
|
|
if (oldprop) {
|
|
/* replace the node */
|
|
newprop->next = oldprop->next;
|
|
*next = newprop;
|
|
oldprop->next = np->deadprops;
|
|
np->deadprops = oldprop;
|
|
} else {
|
|
/* new node */
|
|
newprop->next = NULL;
|
|
*next = newprop;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* of_update_property - Update a property in a node, if the property does
|
|
* not exist, add it.
|
|
*
|
|
* Note that we don't actually remove it, since we have given out
|
|
* who-knows-how-many pointers to the data using get-property.
|
|
* Instead we just move the property to the "dead properties" list,
|
|
* and add the new property to the property list
|
|
*/
|
|
int of_update_property(struct device_node *np, struct property *newprop)
|
|
{
|
|
struct property *oldprop;
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
if (!newprop->name)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&of_mutex);
|
|
|
|
raw_spin_lock_irqsave(&devtree_lock, flags);
|
|
rc = __of_update_property(np, newprop, &oldprop);
|
|
raw_spin_unlock_irqrestore(&devtree_lock, flags);
|
|
|
|
if (!rc)
|
|
__of_update_property_sysfs(np, newprop, oldprop);
|
|
|
|
mutex_unlock(&of_mutex);
|
|
|
|
if (!rc)
|
|
of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void of_alias_add(struct alias_prop *ap, struct device_node *np,
|
|
int id, const char *stem, int stem_len)
|
|
{
|
|
ap->np = np;
|
|
ap->id = id;
|
|
strncpy(ap->stem, stem, stem_len);
|
|
ap->stem[stem_len] = 0;
|
|
list_add_tail(&ap->link, &aliases_lookup);
|
|
pr_debug("adding DT alias:%s: stem=%s id=%i node=%pOF\n",
|
|
ap->alias, ap->stem, ap->id, np);
|
|
}
|
|
|
|
/**
|
|
* of_alias_scan - Scan all properties of the 'aliases' node
|
|
*
|
|
* The function scans all the properties of the 'aliases' node and populates
|
|
* the global lookup table with the properties. It returns the
|
|
* number of alias properties found, or an error code in case of failure.
|
|
*
|
|
* @dt_alloc: An allocator that provides a virtual address to memory
|
|
* for storing the resulting tree
|
|
*/
|
|
void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
|
|
{
|
|
struct property *pp;
|
|
|
|
of_aliases = of_find_node_by_path("/aliases");
|
|
of_chosen = of_find_node_by_path("/chosen");
|
|
if (of_chosen == NULL)
|
|
of_chosen = of_find_node_by_path("/chosen@0");
|
|
|
|
if (of_chosen) {
|
|
/* linux,stdout-path and /aliases/stdout are for legacy compatibility */
|
|
const char *name = NULL;
|
|
|
|
if (of_property_read_string(of_chosen, "stdout-path", &name))
|
|
of_property_read_string(of_chosen, "linux,stdout-path",
|
|
&name);
|
|
if (IS_ENABLED(CONFIG_PPC) && !name)
|
|
of_property_read_string(of_aliases, "stdout", &name);
|
|
if (name)
|
|
of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
|
|
}
|
|
|
|
if (!of_aliases)
|
|
return;
|
|
|
|
for_each_property_of_node(of_aliases, pp) {
|
|
const char *start = pp->name;
|
|
const char *end = start + strlen(start);
|
|
struct device_node *np;
|
|
struct alias_prop *ap;
|
|
int id, len;
|
|
|
|
/* Skip those we do not want to proceed */
|
|
if (!strcmp(pp->name, "name") ||
|
|
!strcmp(pp->name, "phandle") ||
|
|
!strcmp(pp->name, "linux,phandle"))
|
|
continue;
|
|
|
|
np = of_find_node_by_path(pp->value);
|
|
if (!np)
|
|
continue;
|
|
|
|
/* walk the alias backwards to extract the id and work out
|
|
* the 'stem' string */
|
|
while (isdigit(*(end-1)) && end > start)
|
|
end--;
|
|
len = end - start;
|
|
|
|
if (kstrtoint(end, 10, &id) < 0)
|
|
continue;
|
|
|
|
/* Allocate an alias_prop with enough space for the stem */
|
|
ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap));
|
|
if (!ap)
|
|
continue;
|
|
memset(ap, 0, sizeof(*ap) + len + 1);
|
|
ap->alias = start;
|
|
of_alias_add(ap, np, id, start, len);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* of_alias_get_id - Get alias id for the given device_node
|
|
* @np: Pointer to the given device_node
|
|
* @stem: Alias stem of the given device_node
|
|
*
|
|
* The function travels the lookup table to get the alias id for the given
|
|
* device_node and alias stem. It returns the alias id if found.
|
|
*/
|
|
int of_alias_get_id(struct device_node *np, const char *stem)
|
|
{
|
|
struct alias_prop *app;
|
|
int id = -ENODEV;
|
|
|
|
mutex_lock(&of_mutex);
|
|
list_for_each_entry(app, &aliases_lookup, link) {
|
|
if (strcmp(app->stem, stem) != 0)
|
|
continue;
|
|
|
|
if (np == app->np) {
|
|
id = app->id;
|
|
break;
|
|
}
|
|
}
|
|
mutex_unlock(&of_mutex);
|
|
|
|
return id;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_alias_get_id);
|
|
|
|
/**
|
|
* of_alias_get_highest_id - Get highest alias id for the given stem
|
|
* @stem: Alias stem to be examined
|
|
*
|
|
* The function travels the lookup table to get the highest alias id for the
|
|
* given alias stem. It returns the alias id if found.
|
|
*/
|
|
int of_alias_get_highest_id(const char *stem)
|
|
{
|
|
struct alias_prop *app;
|
|
int id = -ENODEV;
|
|
|
|
mutex_lock(&of_mutex);
|
|
list_for_each_entry(app, &aliases_lookup, link) {
|
|
if (strcmp(app->stem, stem) != 0)
|
|
continue;
|
|
|
|
if (app->id > id)
|
|
id = app->id;
|
|
}
|
|
mutex_unlock(&of_mutex);
|
|
|
|
return id;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
|
|
|
|
/**
|
|
* of_console_check() - Test and setup console for DT setup
|
|
* @dn - Pointer to device node
|
|
* @name - Name to use for preferred console without index. ex. "ttyS"
|
|
* @index - Index to use for preferred console.
|
|
*
|
|
* Check if the given device node matches the stdout-path property in the
|
|
* /chosen node. If it does then register it as the preferred console and return
|
|
* TRUE. Otherwise return FALSE.
|
|
*/
|
|
bool of_console_check(struct device_node *dn, char *name, int index)
|
|
{
|
|
if (!dn || dn != of_stdout || console_set_on_cmdline)
|
|
return false;
|
|
|
|
/*
|
|
* XXX: cast `options' to char pointer to suppress complication
|
|
* warnings: printk, UART and console drivers expect char pointer.
|
|
*/
|
|
return !add_preferred_console(name, index, (char *)of_stdout_options);
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_console_check);
|
|
|
|
/**
|
|
* of_find_next_cache_node - Find a node's subsidiary cache
|
|
* @np: node of type "cpu" or "cache"
|
|
*
|
|
* Returns a node pointer with refcount incremented, use
|
|
* of_node_put() on it when done. Caller should hold a reference
|
|
* to np.
|
|
*/
|
|
struct device_node *of_find_next_cache_node(const struct device_node *np)
|
|
{
|
|
struct device_node *child, *cache_node;
|
|
|
|
cache_node = of_parse_phandle(np, "l2-cache", 0);
|
|
if (!cache_node)
|
|
cache_node = of_parse_phandle(np, "next-level-cache", 0);
|
|
|
|
if (cache_node)
|
|
return cache_node;
|
|
|
|
/* OF on pmac has nodes instead of properties named "l2-cache"
|
|
* beneath CPU nodes.
|
|
*/
|
|
if (!strcmp(np->type, "cpu"))
|
|
for_each_child_of_node(np, child)
|
|
if (!strcmp(child->type, "cache"))
|
|
return child;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* of_find_last_cache_level - Find the level at which the last cache is
|
|
* present for the given logical cpu
|
|
*
|
|
* @cpu: cpu number(logical index) for which the last cache level is needed
|
|
*
|
|
* Returns the the level at which the last cache is present. It is exactly
|
|
* same as the total number of cache levels for the given logical cpu.
|
|
*/
|
|
int of_find_last_cache_level(unsigned int cpu)
|
|
{
|
|
u32 cache_level = 0;
|
|
struct device_node *prev = NULL, *np = of_cpu_device_node_get(cpu);
|
|
|
|
while (np) {
|
|
prev = np;
|
|
of_node_put(np);
|
|
np = of_find_next_cache_node(np);
|
|
}
|
|
|
|
of_property_read_u32(prev, "cache-level", &cache_level);
|
|
|
|
return cache_level;
|
|
}
|