linux-stable/drivers/dma/img-mdc-dma.c
Vinod Koul e5a6b3d5de dmaengine: img-mdc: remove unused ‘prev_phys’
In mdc_prep_dma_memcpy(), mdc_prep_dma_cyclic() and mdc_prep_slave_sg()
variable ‘prev_phys’ is initialized but never used, which
leads to warning with W=1

drivers/dma/img-mdc-dma.c: In function ‘mdc_prep_dma_memcpy’:
drivers/dma/img-mdc-dma.c:295:24: warning: variable ‘prev_phys’ set but not used [-Wunused-but-set-variable]
  dma_addr_t curr_phys, prev_phys;

drivers/dma/img-mdc-dma.c: In function ‘mdc_prep_dma_cyclic’:
drivers/dma/img-mdc-dma.c:378:24: warning: variable ‘prev_phys’ set but not used [-Wunused-but-set-variable]
  dma_addr_t curr_phys, prev_phys;

drivers/dma/img-mdc-dma.c: In function ‘mdc_prep_slave_sg’:
drivers/dma/img-mdc-dma.c:461:24: warning: variable ‘prev_phys’ set but not
used [-Wunused-but-set-variable]
  dma_addr_t curr_phys, prev_phys;

So remove it.

Cc: Damien.Horsley <Damien.Horsley@imgtec.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-12-12 22:25:22 +05:30

1024 lines
26 KiB
C

/*
* IMG Multi-threaded DMA Controller (MDC)
*
* Copyright (C) 2009,2012,2013 Imagination Technologies Ltd.
* Copyright (C) 2014 Google, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include "dmaengine.h"
#include "virt-dma.h"
#define MDC_MAX_DMA_CHANNELS 32
#define MDC_GENERAL_CONFIG 0x000
#define MDC_GENERAL_CONFIG_LIST_IEN BIT(31)
#define MDC_GENERAL_CONFIG_IEN BIT(29)
#define MDC_GENERAL_CONFIG_LEVEL_INT BIT(28)
#define MDC_GENERAL_CONFIG_INC_W BIT(12)
#define MDC_GENERAL_CONFIG_INC_R BIT(8)
#define MDC_GENERAL_CONFIG_PHYSICAL_W BIT(7)
#define MDC_GENERAL_CONFIG_WIDTH_W_SHIFT 4
#define MDC_GENERAL_CONFIG_WIDTH_W_MASK 0x7
#define MDC_GENERAL_CONFIG_PHYSICAL_R BIT(3)
#define MDC_GENERAL_CONFIG_WIDTH_R_SHIFT 0
#define MDC_GENERAL_CONFIG_WIDTH_R_MASK 0x7
#define MDC_READ_PORT_CONFIG 0x004
#define MDC_READ_PORT_CONFIG_STHREAD_SHIFT 28
#define MDC_READ_PORT_CONFIG_STHREAD_MASK 0xf
#define MDC_READ_PORT_CONFIG_RTHREAD_SHIFT 24
#define MDC_READ_PORT_CONFIG_RTHREAD_MASK 0xf
#define MDC_READ_PORT_CONFIG_WTHREAD_SHIFT 16
#define MDC_READ_PORT_CONFIG_WTHREAD_MASK 0xf
#define MDC_READ_PORT_CONFIG_BURST_SIZE_SHIFT 4
#define MDC_READ_PORT_CONFIG_BURST_SIZE_MASK 0xff
#define MDC_READ_PORT_CONFIG_DREQ_ENABLE BIT(1)
#define MDC_READ_ADDRESS 0x008
#define MDC_WRITE_ADDRESS 0x00c
#define MDC_TRANSFER_SIZE 0x010
#define MDC_TRANSFER_SIZE_MASK 0xffffff
#define MDC_LIST_NODE_ADDRESS 0x014
#define MDC_CMDS_PROCESSED 0x018
#define MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT 16
#define MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK 0x3f
#define MDC_CMDS_PROCESSED_INT_ACTIVE BIT(8)
#define MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT 0
#define MDC_CMDS_PROCESSED_CMDS_DONE_MASK 0x3f
#define MDC_CONTROL_AND_STATUS 0x01c
#define MDC_CONTROL_AND_STATUS_CANCEL BIT(20)
#define MDC_CONTROL_AND_STATUS_LIST_EN BIT(4)
#define MDC_CONTROL_AND_STATUS_EN BIT(0)
#define MDC_ACTIVE_TRANSFER_SIZE 0x030
#define MDC_GLOBAL_CONFIG_A 0x900
#define MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_SHIFT 16
#define MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_MASK 0xff
#define MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_SHIFT 8
#define MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_MASK 0xff
#define MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_SHIFT 0
#define MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_MASK 0xff
struct mdc_hw_list_desc {
u32 gen_conf;
u32 readport_conf;
u32 read_addr;
u32 write_addr;
u32 xfer_size;
u32 node_addr;
u32 cmds_done;
u32 ctrl_status;
/*
* Not part of the list descriptor, but instead used by the CPU to
* traverse the list.
*/
struct mdc_hw_list_desc *next_desc;
};
struct mdc_tx_desc {
struct mdc_chan *chan;
struct virt_dma_desc vd;
dma_addr_t list_phys;
struct mdc_hw_list_desc *list;
bool cyclic;
bool cmd_loaded;
unsigned int list_len;
unsigned int list_period_len;
size_t list_xfer_size;
unsigned int list_cmds_done;
};
struct mdc_chan {
struct mdc_dma *mdma;
struct virt_dma_chan vc;
struct dma_slave_config config;
struct mdc_tx_desc *desc;
int irq;
unsigned int periph;
unsigned int thread;
unsigned int chan_nr;
};
struct mdc_dma_soc_data {
void (*enable_chan)(struct mdc_chan *mchan);
void (*disable_chan)(struct mdc_chan *mchan);
};
struct mdc_dma {
struct dma_device dma_dev;
void __iomem *regs;
struct clk *clk;
struct dma_pool *desc_pool;
struct regmap *periph_regs;
spinlock_t lock;
unsigned int nr_threads;
unsigned int nr_channels;
unsigned int bus_width;
unsigned int max_burst_mult;
unsigned int max_xfer_size;
const struct mdc_dma_soc_data *soc;
struct mdc_chan channels[MDC_MAX_DMA_CHANNELS];
};
static inline u32 mdc_readl(struct mdc_dma *mdma, u32 reg)
{
return readl(mdma->regs + reg);
}
static inline void mdc_writel(struct mdc_dma *mdma, u32 val, u32 reg)
{
writel(val, mdma->regs + reg);
}
static inline u32 mdc_chan_readl(struct mdc_chan *mchan, u32 reg)
{
return mdc_readl(mchan->mdma, mchan->chan_nr * 0x040 + reg);
}
static inline void mdc_chan_writel(struct mdc_chan *mchan, u32 val, u32 reg)
{
mdc_writel(mchan->mdma, val, mchan->chan_nr * 0x040 + reg);
}
static inline struct mdc_chan *to_mdc_chan(struct dma_chan *c)
{
return container_of(to_virt_chan(c), struct mdc_chan, vc);
}
static inline struct mdc_tx_desc *to_mdc_desc(struct dma_async_tx_descriptor *t)
{
struct virt_dma_desc *vdesc = container_of(t, struct virt_dma_desc, tx);
return container_of(vdesc, struct mdc_tx_desc, vd);
}
static inline struct device *mdma2dev(struct mdc_dma *mdma)
{
return mdma->dma_dev.dev;
}
static inline unsigned int to_mdc_width(unsigned int bytes)
{
return ffs(bytes) - 1;
}
static inline void mdc_set_read_width(struct mdc_hw_list_desc *ldesc,
unsigned int bytes)
{
ldesc->gen_conf |= to_mdc_width(bytes) <<
MDC_GENERAL_CONFIG_WIDTH_R_SHIFT;
}
static inline void mdc_set_write_width(struct mdc_hw_list_desc *ldesc,
unsigned int bytes)
{
ldesc->gen_conf |= to_mdc_width(bytes) <<
MDC_GENERAL_CONFIG_WIDTH_W_SHIFT;
}
static void mdc_list_desc_config(struct mdc_chan *mchan,
struct mdc_hw_list_desc *ldesc,
enum dma_transfer_direction dir,
dma_addr_t src, dma_addr_t dst, size_t len)
{
struct mdc_dma *mdma = mchan->mdma;
unsigned int max_burst, burst_size;
ldesc->gen_conf = MDC_GENERAL_CONFIG_IEN | MDC_GENERAL_CONFIG_LIST_IEN |
MDC_GENERAL_CONFIG_LEVEL_INT | MDC_GENERAL_CONFIG_PHYSICAL_W |
MDC_GENERAL_CONFIG_PHYSICAL_R;
ldesc->readport_conf =
(mchan->thread << MDC_READ_PORT_CONFIG_STHREAD_SHIFT) |
(mchan->thread << MDC_READ_PORT_CONFIG_RTHREAD_SHIFT) |
(mchan->thread << MDC_READ_PORT_CONFIG_WTHREAD_SHIFT);
ldesc->read_addr = src;
ldesc->write_addr = dst;
ldesc->xfer_size = len - 1;
ldesc->node_addr = 0;
ldesc->cmds_done = 0;
ldesc->ctrl_status = MDC_CONTROL_AND_STATUS_LIST_EN |
MDC_CONTROL_AND_STATUS_EN;
ldesc->next_desc = NULL;
if (IS_ALIGNED(dst, mdma->bus_width) &&
IS_ALIGNED(src, mdma->bus_width))
max_burst = mdma->bus_width * mdma->max_burst_mult;
else
max_burst = mdma->bus_width * (mdma->max_burst_mult - 1);
if (dir == DMA_MEM_TO_DEV) {
ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_R;
ldesc->readport_conf |= MDC_READ_PORT_CONFIG_DREQ_ENABLE;
mdc_set_read_width(ldesc, mdma->bus_width);
mdc_set_write_width(ldesc, mchan->config.dst_addr_width);
burst_size = min(max_burst, mchan->config.dst_maxburst *
mchan->config.dst_addr_width);
} else if (dir == DMA_DEV_TO_MEM) {
ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_W;
ldesc->readport_conf |= MDC_READ_PORT_CONFIG_DREQ_ENABLE;
mdc_set_read_width(ldesc, mchan->config.src_addr_width);
mdc_set_write_width(ldesc, mdma->bus_width);
burst_size = min(max_burst, mchan->config.src_maxburst *
mchan->config.src_addr_width);
} else {
ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_R |
MDC_GENERAL_CONFIG_INC_W;
mdc_set_read_width(ldesc, mdma->bus_width);
mdc_set_write_width(ldesc, mdma->bus_width);
burst_size = max_burst;
}
ldesc->readport_conf |= (burst_size - 1) <<
MDC_READ_PORT_CONFIG_BURST_SIZE_SHIFT;
}
static void mdc_list_desc_free(struct mdc_tx_desc *mdesc)
{
struct mdc_dma *mdma = mdesc->chan->mdma;
struct mdc_hw_list_desc *curr, *next;
dma_addr_t curr_phys, next_phys;
curr = mdesc->list;
curr_phys = mdesc->list_phys;
while (curr) {
next = curr->next_desc;
next_phys = curr->node_addr;
dma_pool_free(mdma->desc_pool, curr, curr_phys);
curr = next;
curr_phys = next_phys;
}
}
static void mdc_desc_free(struct virt_dma_desc *vd)
{
struct mdc_tx_desc *mdesc = to_mdc_desc(&vd->tx);
mdc_list_desc_free(mdesc);
kfree(mdesc);
}
static struct dma_async_tx_descriptor *mdc_prep_dma_memcpy(
struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len,
unsigned long flags)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_dma *mdma = mchan->mdma;
struct mdc_tx_desc *mdesc;
struct mdc_hw_list_desc *curr, *prev = NULL;
dma_addr_t curr_phys;
if (!len)
return NULL;
mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT);
if (!mdesc)
return NULL;
mdesc->chan = mchan;
mdesc->list_xfer_size = len;
while (len > 0) {
size_t xfer_size;
curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT, &curr_phys);
if (!curr)
goto free_desc;
if (prev) {
prev->node_addr = curr_phys;
prev->next_desc = curr;
} else {
mdesc->list_phys = curr_phys;
mdesc->list = curr;
}
xfer_size = min_t(size_t, mdma->max_xfer_size, len);
mdc_list_desc_config(mchan, curr, DMA_MEM_TO_MEM, src, dest,
xfer_size);
prev = curr;
mdesc->list_len++;
src += xfer_size;
dest += xfer_size;
len -= xfer_size;
}
return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags);
free_desc:
mdc_desc_free(&mdesc->vd);
return NULL;
}
static int mdc_check_slave_width(struct mdc_chan *mchan,
enum dma_transfer_direction dir)
{
enum dma_slave_buswidth width;
if (dir == DMA_MEM_TO_DEV)
width = mchan->config.dst_addr_width;
else
width = mchan->config.src_addr_width;
switch (width) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
case DMA_SLAVE_BUSWIDTH_2_BYTES:
case DMA_SLAVE_BUSWIDTH_4_BYTES:
case DMA_SLAVE_BUSWIDTH_8_BYTES:
break;
default:
return -EINVAL;
}
if (width > mchan->mdma->bus_width)
return -EINVAL;
return 0;
}
static struct dma_async_tx_descriptor *mdc_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction dir,
unsigned long flags)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_dma *mdma = mchan->mdma;
struct mdc_tx_desc *mdesc;
struct mdc_hw_list_desc *curr, *prev = NULL;
dma_addr_t curr_phys;
if (!buf_len && !period_len)
return NULL;
if (!is_slave_direction(dir))
return NULL;
if (mdc_check_slave_width(mchan, dir) < 0)
return NULL;
mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT);
if (!mdesc)
return NULL;
mdesc->chan = mchan;
mdesc->cyclic = true;
mdesc->list_xfer_size = buf_len;
mdesc->list_period_len = DIV_ROUND_UP(period_len,
mdma->max_xfer_size);
while (buf_len > 0) {
size_t remainder = min(period_len, buf_len);
while (remainder > 0) {
size_t xfer_size;
curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT,
&curr_phys);
if (!curr)
goto free_desc;
if (!prev) {
mdesc->list_phys = curr_phys;
mdesc->list = curr;
} else {
prev->node_addr = curr_phys;
prev->next_desc = curr;
}
xfer_size = min_t(size_t, mdma->max_xfer_size,
remainder);
if (dir == DMA_MEM_TO_DEV) {
mdc_list_desc_config(mchan, curr, dir,
buf_addr,
mchan->config.dst_addr,
xfer_size);
} else {
mdc_list_desc_config(mchan, curr, dir,
mchan->config.src_addr,
buf_addr,
xfer_size);
}
prev = curr;
mdesc->list_len++;
buf_addr += xfer_size;
buf_len -= xfer_size;
remainder -= xfer_size;
}
}
prev->node_addr = mdesc->list_phys;
return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags);
free_desc:
mdc_desc_free(&mdesc->vd);
return NULL;
}
static struct dma_async_tx_descriptor *mdc_prep_slave_sg(
struct dma_chan *chan, struct scatterlist *sgl,
unsigned int sg_len, enum dma_transfer_direction dir,
unsigned long flags, void *context)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_dma *mdma = mchan->mdma;
struct mdc_tx_desc *mdesc;
struct scatterlist *sg;
struct mdc_hw_list_desc *curr, *prev = NULL;
dma_addr_t curr_phys;
unsigned int i;
if (!sgl)
return NULL;
if (!is_slave_direction(dir))
return NULL;
if (mdc_check_slave_width(mchan, dir) < 0)
return NULL;
mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT);
if (!mdesc)
return NULL;
mdesc->chan = mchan;
for_each_sg(sgl, sg, sg_len, i) {
dma_addr_t buf = sg_dma_address(sg);
size_t buf_len = sg_dma_len(sg);
while (buf_len > 0) {
size_t xfer_size;
curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT,
&curr_phys);
if (!curr)
goto free_desc;
if (!prev) {
mdesc->list_phys = curr_phys;
mdesc->list = curr;
} else {
prev->node_addr = curr_phys;
prev->next_desc = curr;
}
xfer_size = min_t(size_t, mdma->max_xfer_size,
buf_len);
if (dir == DMA_MEM_TO_DEV) {
mdc_list_desc_config(mchan, curr, dir, buf,
mchan->config.dst_addr,
xfer_size);
} else {
mdc_list_desc_config(mchan, curr, dir,
mchan->config.src_addr,
buf, xfer_size);
}
prev = curr;
mdesc->list_len++;
mdesc->list_xfer_size += xfer_size;
buf += xfer_size;
buf_len -= xfer_size;
}
}
return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags);
free_desc:
mdc_desc_free(&mdesc->vd);
return NULL;
}
static void mdc_issue_desc(struct mdc_chan *mchan)
{
struct mdc_dma *mdma = mchan->mdma;
struct virt_dma_desc *vd;
struct mdc_tx_desc *mdesc;
u32 val;
vd = vchan_next_desc(&mchan->vc);
if (!vd)
return;
list_del(&vd->node);
mdesc = to_mdc_desc(&vd->tx);
mchan->desc = mdesc;
dev_dbg(mdma2dev(mdma), "Issuing descriptor on channel %d\n",
mchan->chan_nr);
mdma->soc->enable_chan(mchan);
val = mdc_chan_readl(mchan, MDC_GENERAL_CONFIG);
val |= MDC_GENERAL_CONFIG_LIST_IEN | MDC_GENERAL_CONFIG_IEN |
MDC_GENERAL_CONFIG_LEVEL_INT | MDC_GENERAL_CONFIG_PHYSICAL_W |
MDC_GENERAL_CONFIG_PHYSICAL_R;
mdc_chan_writel(mchan, val, MDC_GENERAL_CONFIG);
val = (mchan->thread << MDC_READ_PORT_CONFIG_STHREAD_SHIFT) |
(mchan->thread << MDC_READ_PORT_CONFIG_RTHREAD_SHIFT) |
(mchan->thread << MDC_READ_PORT_CONFIG_WTHREAD_SHIFT);
mdc_chan_writel(mchan, val, MDC_READ_PORT_CONFIG);
mdc_chan_writel(mchan, mdesc->list_phys, MDC_LIST_NODE_ADDRESS);
val = mdc_chan_readl(mchan, MDC_CONTROL_AND_STATUS);
val |= MDC_CONTROL_AND_STATUS_LIST_EN;
mdc_chan_writel(mchan, val, MDC_CONTROL_AND_STATUS);
}
static void mdc_issue_pending(struct dma_chan *chan)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
unsigned long flags;
spin_lock_irqsave(&mchan->vc.lock, flags);
if (vchan_issue_pending(&mchan->vc) && !mchan->desc)
mdc_issue_desc(mchan);
spin_unlock_irqrestore(&mchan->vc.lock, flags);
}
static enum dma_status mdc_tx_status(struct dma_chan *chan,
dma_cookie_t cookie, struct dma_tx_state *txstate)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_tx_desc *mdesc;
struct virt_dma_desc *vd;
unsigned long flags;
size_t bytes = 0;
int ret;
ret = dma_cookie_status(chan, cookie, txstate);
if (ret == DMA_COMPLETE)
return ret;
if (!txstate)
return ret;
spin_lock_irqsave(&mchan->vc.lock, flags);
vd = vchan_find_desc(&mchan->vc, cookie);
if (vd) {
mdesc = to_mdc_desc(&vd->tx);
bytes = mdesc->list_xfer_size;
} else if (mchan->desc && mchan->desc->vd.tx.cookie == cookie) {
struct mdc_hw_list_desc *ldesc;
u32 val1, val2, done, processed, residue;
int i, cmds;
mdesc = mchan->desc;
/*
* Determine the number of commands that haven't been
* processed (handled by the IRQ handler) yet.
*/
do {
val1 = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED) &
~MDC_CMDS_PROCESSED_INT_ACTIVE;
residue = mdc_chan_readl(mchan,
MDC_ACTIVE_TRANSFER_SIZE);
val2 = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED) &
~MDC_CMDS_PROCESSED_INT_ACTIVE;
} while (val1 != val2);
done = (val1 >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) &
MDC_CMDS_PROCESSED_CMDS_DONE_MASK;
processed = (val1 >> MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) &
MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK;
cmds = (done - processed) %
(MDC_CMDS_PROCESSED_CMDS_DONE_MASK + 1);
/*
* If the command loaded event hasn't been processed yet, then
* the difference above includes an extra command.
*/
if (!mdesc->cmd_loaded)
cmds--;
else
cmds += mdesc->list_cmds_done;
bytes = mdesc->list_xfer_size;
ldesc = mdesc->list;
for (i = 0; i < cmds; i++) {
bytes -= ldesc->xfer_size + 1;
ldesc = ldesc->next_desc;
}
if (ldesc) {
if (residue != MDC_TRANSFER_SIZE_MASK)
bytes -= ldesc->xfer_size - residue;
else
bytes -= ldesc->xfer_size + 1;
}
}
spin_unlock_irqrestore(&mchan->vc.lock, flags);
dma_set_residue(txstate, bytes);
return ret;
}
static unsigned int mdc_get_new_events(struct mdc_chan *mchan)
{
u32 val, processed, done1, done2;
unsigned int ret;
val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED);
processed = (val >> MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) &
MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK;
/*
* CMDS_DONE may have incremented between reading CMDS_PROCESSED
* and clearing INT_ACTIVE. Re-read CMDS_PROCESSED to ensure we
* didn't miss a command completion.
*/
do {
val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED);
done1 = (val >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) &
MDC_CMDS_PROCESSED_CMDS_DONE_MASK;
val &= ~((MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK <<
MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) |
MDC_CMDS_PROCESSED_INT_ACTIVE);
val |= done1 << MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT;
mdc_chan_writel(mchan, val, MDC_CMDS_PROCESSED);
val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED);
done2 = (val >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) &
MDC_CMDS_PROCESSED_CMDS_DONE_MASK;
} while (done1 != done2);
if (done1 >= processed)
ret = done1 - processed;
else
ret = ((MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK + 1) -
processed) + done1;
return ret;
}
static int mdc_terminate_all(struct dma_chan *chan)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_tx_desc *mdesc;
unsigned long flags;
LIST_HEAD(head);
spin_lock_irqsave(&mchan->vc.lock, flags);
mdc_chan_writel(mchan, MDC_CONTROL_AND_STATUS_CANCEL,
MDC_CONTROL_AND_STATUS);
mdesc = mchan->desc;
mchan->desc = NULL;
vchan_get_all_descriptors(&mchan->vc, &head);
mdc_get_new_events(mchan);
spin_unlock_irqrestore(&mchan->vc.lock, flags);
if (mdesc)
mdc_desc_free(&mdesc->vd);
vchan_dma_desc_free_list(&mchan->vc, &head);
return 0;
}
static int mdc_slave_config(struct dma_chan *chan,
struct dma_slave_config *config)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
unsigned long flags;
spin_lock_irqsave(&mchan->vc.lock, flags);
mchan->config = *config;
spin_unlock_irqrestore(&mchan->vc.lock, flags);
return 0;
}
static void mdc_free_chan_resources(struct dma_chan *chan)
{
struct mdc_chan *mchan = to_mdc_chan(chan);
struct mdc_dma *mdma = mchan->mdma;
mdc_terminate_all(chan);
mdma->soc->disable_chan(mchan);
}
static irqreturn_t mdc_chan_irq(int irq, void *dev_id)
{
struct mdc_chan *mchan = (struct mdc_chan *)dev_id;
struct mdc_tx_desc *mdesc;
unsigned int i, new_events;
spin_lock(&mchan->vc.lock);
dev_dbg(mdma2dev(mchan->mdma), "IRQ on channel %d\n", mchan->chan_nr);
new_events = mdc_get_new_events(mchan);
if (!new_events)
goto out;
mdesc = mchan->desc;
if (!mdesc) {
dev_warn(mdma2dev(mchan->mdma),
"IRQ with no active descriptor on channel %d\n",
mchan->chan_nr);
goto out;
}
for (i = 0; i < new_events; i++) {
/*
* The first interrupt in a transfer indicates that the
* command list has been loaded, not that a command has
* been completed.
*/
if (!mdesc->cmd_loaded) {
mdesc->cmd_loaded = true;
continue;
}
mdesc->list_cmds_done++;
if (mdesc->cyclic) {
mdesc->list_cmds_done %= mdesc->list_len;
if (mdesc->list_cmds_done % mdesc->list_period_len == 0)
vchan_cyclic_callback(&mdesc->vd);
} else if (mdesc->list_cmds_done == mdesc->list_len) {
mchan->desc = NULL;
vchan_cookie_complete(&mdesc->vd);
mdc_issue_desc(mchan);
break;
}
}
out:
spin_unlock(&mchan->vc.lock);
return IRQ_HANDLED;
}
static struct dma_chan *mdc_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct mdc_dma *mdma = ofdma->of_dma_data;
struct dma_chan *chan;
if (dma_spec->args_count != 3)
return NULL;
list_for_each_entry(chan, &mdma->dma_dev.channels, device_node) {
struct mdc_chan *mchan = to_mdc_chan(chan);
if (!(dma_spec->args[1] & BIT(mchan->chan_nr)))
continue;
if (dma_get_slave_channel(chan)) {
mchan->periph = dma_spec->args[0];
mchan->thread = dma_spec->args[2];
return chan;
}
}
return NULL;
}
#define PISTACHIO_CR_PERIPH_DMA_ROUTE(ch) (0x120 + 0x4 * ((ch) / 4))
#define PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(ch) (8 * ((ch) % 4))
#define PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK 0x3f
static void pistachio_mdc_enable_chan(struct mdc_chan *mchan)
{
struct mdc_dma *mdma = mchan->mdma;
regmap_update_bits(mdma->periph_regs,
PISTACHIO_CR_PERIPH_DMA_ROUTE(mchan->chan_nr),
PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK <<
PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr),
mchan->periph <<
PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr));
}
static void pistachio_mdc_disable_chan(struct mdc_chan *mchan)
{
struct mdc_dma *mdma = mchan->mdma;
regmap_update_bits(mdma->periph_regs,
PISTACHIO_CR_PERIPH_DMA_ROUTE(mchan->chan_nr),
PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK <<
PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr),
0);
}
static const struct mdc_dma_soc_data pistachio_mdc_data = {
.enable_chan = pistachio_mdc_enable_chan,
.disable_chan = pistachio_mdc_disable_chan,
};
static const struct of_device_id mdc_dma_of_match[] = {
{ .compatible = "img,pistachio-mdc-dma", .data = &pistachio_mdc_data, },
{ },
};
MODULE_DEVICE_TABLE(of, mdc_dma_of_match);
static int mdc_dma_probe(struct platform_device *pdev)
{
struct mdc_dma *mdma;
struct resource *res;
unsigned int i;
u32 val;
int ret;
mdma = devm_kzalloc(&pdev->dev, sizeof(*mdma), GFP_KERNEL);
if (!mdma)
return -ENOMEM;
platform_set_drvdata(pdev, mdma);
mdma->soc = of_device_get_match_data(&pdev->dev);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mdma->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(mdma->regs))
return PTR_ERR(mdma->regs);
mdma->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"img,cr-periph");
if (IS_ERR(mdma->periph_regs))
return PTR_ERR(mdma->periph_regs);
mdma->clk = devm_clk_get(&pdev->dev, "sys");
if (IS_ERR(mdma->clk))
return PTR_ERR(mdma->clk);
ret = clk_prepare_enable(mdma->clk);
if (ret)
return ret;
dma_cap_zero(mdma->dma_dev.cap_mask);
dma_cap_set(DMA_SLAVE, mdma->dma_dev.cap_mask);
dma_cap_set(DMA_PRIVATE, mdma->dma_dev.cap_mask);
dma_cap_set(DMA_CYCLIC, mdma->dma_dev.cap_mask);
dma_cap_set(DMA_MEMCPY, mdma->dma_dev.cap_mask);
val = mdc_readl(mdma, MDC_GLOBAL_CONFIG_A);
mdma->nr_channels = (val >> MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_SHIFT) &
MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_MASK;
mdma->nr_threads =
1 << ((val >> MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_SHIFT) &
MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_MASK);
mdma->bus_width =
(1 << ((val >> MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_SHIFT) &
MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_MASK)) / 8;
/*
* Although transfer sizes of up to MDC_TRANSFER_SIZE_MASK + 1 bytes
* are supported, this makes it possible for the value reported in
* MDC_ACTIVE_TRANSFER_SIZE to be ambiguous - an active transfer size
* of MDC_TRANSFER_SIZE_MASK may indicate either that 0 bytes or
* MDC_TRANSFER_SIZE_MASK + 1 bytes are remaining. To eliminate this
* ambiguity, restrict transfer sizes to one bus-width less than the
* actual maximum.
*/
mdma->max_xfer_size = MDC_TRANSFER_SIZE_MASK + 1 - mdma->bus_width;
of_property_read_u32(pdev->dev.of_node, "dma-channels",
&mdma->nr_channels);
ret = of_property_read_u32(pdev->dev.of_node,
"img,max-burst-multiplier",
&mdma->max_burst_mult);
if (ret)
goto disable_clk;
mdma->dma_dev.dev = &pdev->dev;
mdma->dma_dev.device_prep_slave_sg = mdc_prep_slave_sg;
mdma->dma_dev.device_prep_dma_cyclic = mdc_prep_dma_cyclic;
mdma->dma_dev.device_prep_dma_memcpy = mdc_prep_dma_memcpy;
mdma->dma_dev.device_free_chan_resources = mdc_free_chan_resources;
mdma->dma_dev.device_tx_status = mdc_tx_status;
mdma->dma_dev.device_issue_pending = mdc_issue_pending;
mdma->dma_dev.device_terminate_all = mdc_terminate_all;
mdma->dma_dev.device_config = mdc_slave_config;
mdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
mdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
for (i = 1; i <= mdma->bus_width; i <<= 1) {
mdma->dma_dev.src_addr_widths |= BIT(i);
mdma->dma_dev.dst_addr_widths |= BIT(i);
}
INIT_LIST_HEAD(&mdma->dma_dev.channels);
for (i = 0; i < mdma->nr_channels; i++) {
struct mdc_chan *mchan = &mdma->channels[i];
mchan->mdma = mdma;
mchan->chan_nr = i;
mchan->irq = platform_get_irq(pdev, i);
if (mchan->irq < 0) {
ret = mchan->irq;
goto disable_clk;
}
ret = devm_request_irq(&pdev->dev, mchan->irq, mdc_chan_irq,
IRQ_TYPE_LEVEL_HIGH,
dev_name(&pdev->dev), mchan);
if (ret < 0)
goto disable_clk;
mchan->vc.desc_free = mdc_desc_free;
vchan_init(&mchan->vc, &mdma->dma_dev);
}
mdma->desc_pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
sizeof(struct mdc_hw_list_desc),
4, 0);
if (!mdma->desc_pool) {
ret = -ENOMEM;
goto disable_clk;
}
ret = dma_async_device_register(&mdma->dma_dev);
if (ret)
goto disable_clk;
ret = of_dma_controller_register(pdev->dev.of_node, mdc_of_xlate, mdma);
if (ret)
goto unregister;
dev_info(&pdev->dev, "MDC with %u channels and %u threads\n",
mdma->nr_channels, mdma->nr_threads);
return 0;
unregister:
dma_async_device_unregister(&mdma->dma_dev);
disable_clk:
clk_disable_unprepare(mdma->clk);
return ret;
}
static int mdc_dma_remove(struct platform_device *pdev)
{
struct mdc_dma *mdma = platform_get_drvdata(pdev);
struct mdc_chan *mchan, *next;
of_dma_controller_free(pdev->dev.of_node);
dma_async_device_unregister(&mdma->dma_dev);
list_for_each_entry_safe(mchan, next, &mdma->dma_dev.channels,
vc.chan.device_node) {
list_del(&mchan->vc.chan.device_node);
devm_free_irq(&pdev->dev, mchan->irq, mchan);
tasklet_kill(&mchan->vc.task);
}
clk_disable_unprepare(mdma->clk);
return 0;
}
static struct platform_driver mdc_dma_driver = {
.driver = {
.name = "img-mdc-dma",
.of_match_table = of_match_ptr(mdc_dma_of_match),
},
.probe = mdc_dma_probe,
.remove = mdc_dma_remove,
};
module_platform_driver(mdc_dma_driver);
MODULE_DESCRIPTION("IMG Multi-threaded DMA Controller (MDC) driver");
MODULE_AUTHOR("Andrew Bresticker <abrestic@chromium.org>");
MODULE_LICENSE("GPL v2");