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dma40: Improve the logic of stopping logical chan

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can be directly stopped by issuing a SUSPEND_REQ on the EE
bits. There is no need to suspend the physical channel and
restart it.

Also, the support for pre-V2 hw is discontinued.

EE bits for writing:

00: disable only if AS=11 or AS=00
01: enable
10: suspend_req only if AS=01 & EE=01 or EE=11
11: round / no change for writing

Signed-off-by: Narayanan G <narayanan.gopalakrishnan@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
This commit is contained in:
Narayanan G 2012-02-09 12:41:37 +05:30 committed by Vinod Koul
parent ed8b0d67f3
commit 1bdae6f49c
2 changed files with 202 additions and 126 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

326
drivers/dma/ste_dma40.c
View File

@ -68,6 +68,22 @@ enum d40_command {
D40_DMA_SUSPENDED = 3
};
/*
* enum d40_events - The different Event Enables for the event lines.
*
* @D40_DEACTIVATE_EVENTLINE: De-activate Event line, stopping the logical chan.
* @D40_ACTIVATE_EVENTLINE: Activate the Event line, to start a logical chan.
* @D40_SUSPEND_REQ_EVENTLINE: Requesting for suspending a event line.
* @D40_ROUND_EVENTLINE: Status check for event line.
*/
enum d40_events {
D40_DEACTIVATE_EVENTLINE = 0,
D40_ACTIVATE_EVENTLINE = 1,
D40_SUSPEND_REQ_EVENTLINE = 2,
D40_ROUND_EVENTLINE = 3
};
/*
* These are the registers that has to be saved and later restored
* when the DMA hw is powered off.
@ -870,8 +886,8 @@ static void d40_save_restore_registers(struct d40_base *base, bool save)
}
#endif
static int d40_channel_execute_command(struct d40_chan *d40c,
enum d40_command command)
static int __d40_execute_command_phy(struct d40_chan *d40c,
enum d40_command command)
{
u32 status;
int i;
@ -880,6 +896,12 @@ static int d40_channel_execute_command(struct d40_chan *d40c,
unsigned long flags;
u32 wmask;
if (command == D40_DMA_STOP) {
ret = __d40_execute_command_phy(d40c, D40_DMA_SUSPEND_REQ);
if (ret)
return ret;
}
spin_lock_irqsave(&d40c->base->execmd_lock, flags);
if (d40c->phy_chan->num % 2 == 0)
@ -973,67 +995,109 @@ static void d40_term_all(struct d40_chan *d40c)
}
d40c->pending_tx = 0;
d40c->busy = false;
}
static void __d40_config_set_event(struct d40_chan *d40c, bool enable,
u32 event, int reg)
static void __d40_config_set_event(struct d40_chan *d40c,
enum d40_events event_type, u32 event,
int reg)
{
void __iomem *addr = chan_base(d40c) + reg;
int tries;
u32 status;
switch (event_type) {
case D40_DEACTIVATE_EVENTLINE:
if (!enable) {
writel((D40_DEACTIVATE_EVENTLINE << D40_EVENTLINE_POS(event))
| ~D40_EVENTLINE_MASK(event), addr);
return;
}
break;
case D40_SUSPEND_REQ_EVENTLINE:
status = (readl(addr) & D40_EVENTLINE_MASK(event)) >>
D40_EVENTLINE_POS(event);
if (status == D40_DEACTIVATE_EVENTLINE ||
status == D40_SUSPEND_REQ_EVENTLINE)
break;
writel((D40_SUSPEND_REQ_EVENTLINE << D40_EVENTLINE_POS(event))
| ~D40_EVENTLINE_MASK(event), addr);
for (tries = 0 ; tries < D40_SUSPEND_MAX_IT; tries++) {
status = (readl(addr) & D40_EVENTLINE_MASK(event)) >>
D40_EVENTLINE_POS(event);
cpu_relax();
/*
* Reduce the number of bus accesses while
* waiting for the DMA to suspend.
*/
udelay(3);
if (status == D40_DEACTIVATE_EVENTLINE)
break;
}
if (tries == D40_SUSPEND_MAX_IT) {
chan_err(d40c,
"unable to stop the event_line chl %d (log: %d)"
"status %x\n", d40c->phy_chan->num,
d40c->log_num, status);
}
break;
case D40_ACTIVATE_EVENTLINE:
/*
* The hardware sometimes doesn't register the enable when src and dst
* event lines are active on the same logical channel. Retry to ensure
* it does. Usually only one retry is sufficient.
*/
tries = 100;
while (--tries) {
writel((D40_ACTIVATE_EVENTLINE << D40_EVENTLINE_POS(event))
| ~D40_EVENTLINE_MASK(event), addr);
tries = 100;
while (--tries) {
writel((D40_ACTIVATE_EVENTLINE <<
D40_EVENTLINE_POS(event)) |
~D40_EVENTLINE_MASK(event), addr);
if (readl(addr) & D40_EVENTLINE_MASK(event))
break;
}
if (tries != 99)
dev_dbg(chan2dev(d40c),
"[%s] workaround enable S%cLNK (%d tries)\n",
__func__, reg == D40_CHAN_REG_SSLNK ? 'S' : 'D',
100 - tries);
WARN_ON(!tries);
break;
case D40_ROUND_EVENTLINE:
BUG();
break;
if (readl(addr) & D40_EVENTLINE_MASK(event))
break;
}
if (tries != 99)
dev_dbg(chan2dev(d40c),
"[%s] workaround enable S%cLNK (%d tries)\n",
__func__, reg == D40_CHAN_REG_SSLNK ? 'S' : 'D',
100 - tries);
WARN_ON(!tries);
}
static void d40_config_set_event(struct d40_chan *d40c, bool do_enable)
static void d40_config_set_event(struct d40_chan *d40c,
enum d40_events event_type)
{
unsigned long flags;
spin_lock_irqsave(&d40c->phy_chan->lock, flags);
/* Enable event line connected to device (or memcpy) */
if ((d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM) ||
(d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH)) {
u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type);
__d40_config_set_event(d40c, do_enable, event,
__d40_config_set_event(d40c, event_type, event,
D40_CHAN_REG_SSLNK);
}
if (d40c->dma_cfg.dir != STEDMA40_PERIPH_TO_MEM) {
u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
__d40_config_set_event(d40c, do_enable, event,
__d40_config_set_event(d40c, event_type, event,
D40_CHAN_REG_SDLNK);
}
spin_unlock_irqrestore(&d40c->phy_chan->lock, flags);
}
static u32 d40_chan_has_events(struct d40_chan *d40c)
@ -1047,6 +1111,64 @@ static u32 d40_chan_has_events(struct d40_chan *d40c)
return val;
}
static int
__d40_execute_command_log(struct d40_chan *d40c, enum d40_command command)
{
unsigned long flags;
int ret = 0;
u32 active_status;
void __iomem *active_reg;
if (d40c->phy_chan->num % 2 == 0)
active_reg = d40c->base->virtbase + D40_DREG_ACTIVE;
else
active_reg = d40c->base->virtbase + D40_DREG_ACTIVO;
spin_lock_irqsave(&d40c->phy_chan->lock, flags);
switch (command) {
case D40_DMA_STOP:
case D40_DMA_SUSPEND_REQ:
active_status = (readl(active_reg) &
D40_CHAN_POS_MASK(d40c->phy_chan->num)) >>
D40_CHAN_POS(d40c->phy_chan->num);
if (active_status == D40_DMA_RUN)
d40_config_set_event(d40c, D40_SUSPEND_REQ_EVENTLINE);
else
d40_config_set_event(d40c, D40_DEACTIVATE_EVENTLINE);
if (!d40_chan_has_events(d40c) && (command == D40_DMA_STOP))
ret = __d40_execute_command_phy(d40c, command);
break;
case D40_DMA_RUN:
d40_config_set_event(d40c, D40_ACTIVATE_EVENTLINE);
ret = __d40_execute_command_phy(d40c, command);
break;
case D40_DMA_SUSPENDED:
BUG();
break;
}
spin_unlock_irqrestore(&d40c->phy_chan->lock, flags);
return ret;
}
static int d40_channel_execute_command(struct d40_chan *d40c,
enum d40_command command)
{
if (chan_is_logical(d40c))
return __d40_execute_command_log(d40c, command);
else
return __d40_execute_command_phy(d40c, command);
}
static u32 d40_get_prmo(struct d40_chan *d40c)
{
static const unsigned int phy_map[] = {
@ -1149,15 +1271,7 @@ static int d40_pause(struct d40_chan *d40c)
spin_lock_irqsave(&d40c->lock, flags);
res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
if (res == 0) {
if (chan_is_logical(d40c)) {
d40_config_set_event(d40c, false);
/* Resume the other logical channels if any */
if (d40_chan_has_events(d40c))
res = d40_channel_execute_command(d40c,
D40_DMA_RUN);
}
}
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
spin_unlock_irqrestore(&d40c->lock, flags);
@ -1174,45 +1288,17 @@ static int d40_resume(struct d40_chan *d40c)
spin_lock_irqsave(&d40c->lock, flags);
pm_runtime_get_sync(d40c->base->dev);
if (d40c->base->rev == 0)
if (chan_is_logical(d40c)) {
res = d40_channel_execute_command(d40c,
D40_DMA_SUSPEND_REQ);
goto no_suspend;
}
/* If bytes left to transfer or linked tx resume job */
if (d40_residue(d40c) || d40_tx_is_linked(d40c)) {
if (chan_is_logical(d40c))
d40_config_set_event(d40c, true);
if (d40_residue(d40c) || d40_tx_is_linked(d40c))
res = d40_channel_execute_command(d40c, D40_DMA_RUN);
}
no_suspend:
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
spin_unlock_irqrestore(&d40c->lock, flags);
return res;
}
static int d40_terminate_all(struct d40_chan *chan)
{
unsigned long flags;
int ret = 0;
ret = d40_pause(chan);
if (!ret && chan_is_physical(chan))
ret = d40_channel_execute_command(chan, D40_DMA_STOP);
spin_lock_irqsave(&chan->lock, flags);
d40_term_all(chan);
spin_unlock_irqrestore(&chan->lock, flags);
return ret;
}
static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct d40_chan *d40c = container_of(tx->chan,
@ -1232,20 +1318,6 @@ static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)
static int d40_start(struct d40_chan *d40c)
{
if (d40c->base->rev == 0) {
int err;
if (chan_is_logical(d40c)) {
err = d40_channel_execute_command(d40c,
D40_DMA_SUSPEND_REQ);
if (err)
return err;
}
}
if (chan_is_logical(d40c))
d40_config_set_event(d40c, true);
return d40_channel_execute_command(d40c, D40_DMA_RUN);
}
@ -1258,10 +1330,10 @@ static struct d40_desc *d40_queue_start(struct d40_chan *d40c)
d40d = d40_first_queued(d40c);
if (d40d != NULL) {
if (!d40c->busy)
if (!d40c->busy) {
d40c->busy = true;
pm_runtime_get_sync(d40c->base->dev);
pm_runtime_get_sync(d40c->base->dev);
}
/* Remove from queue */
d40_desc_remove(d40d);
@ -1388,8 +1460,8 @@ static void dma_tasklet(unsigned long data)
return;
err:
/* Rescue manoeuvre if receiving double interrupts */
err:
/* Rescue manouver if receiving double interrupts */
if (d40c->pending_tx > 0)
d40c->pending_tx--;
spin_unlock_irqrestore(&d40c->lock, flags);
@ -1770,7 +1842,6 @@ static int d40_config_memcpy(struct d40_chan *d40c)
return 0;
}
static int d40_free_dma(struct d40_chan *d40c)
{
@ -1806,44 +1877,19 @@ static int d40_free_dma(struct d40_chan *d40c)
}
pm_runtime_get_sync(d40c->base->dev);
res = d40_channel_execute_command(d40c, D40_DMA_SUSPEND_REQ);
if (res) {
chan_err(d40c, "suspend failed\n");
goto out;
}
if (chan_is_logical(d40c)) {
/* Release logical channel, deactivate the event line */
d40_config_set_event(d40c, false);
d40c->base->lookup_log_chans[d40c->log_num] = NULL;
/*
* Check if there are more logical allocation
* on this phy channel.
*/
if (!d40_alloc_mask_free(phy, is_src, event)) {
/* Resume the other logical channels if any */
if (d40_chan_has_events(d40c)) {
res = d40_channel_execute_command(d40c,
D40_DMA_RUN);
if (res)
chan_err(d40c,
"Executing RUN command\n");
}
goto out;
}
} else {
(void) d40_alloc_mask_free(phy, is_src, 0);
}
/* Release physical channel */
res = d40_channel_execute_command(d40c, D40_DMA_STOP);
if (res) {
chan_err(d40c, "Failed to stop channel\n");
chan_err(d40c, "stop failed\n");
goto out;
}
d40_alloc_mask_free(phy, is_src, chan_is_logical(d40c) ? event : 0);
if (chan_is_logical(d40c))
d40c->base->lookup_log_chans[d40c->log_num] = NULL;
else
d40c->base->lookup_phy_chans[phy->num] = NULL;
if (d40c->busy) {
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
@ -1852,7 +1898,6 @@ static int d40_free_dma(struct d40_chan *d40c)
d40c->busy = false;
d40c->phy_chan = NULL;
d40c->configured = false;
d40c->base->lookup_phy_chans[phy->num] = NULL;
out:
pm_runtime_mark_last_busy(d40c->base->dev);
@ -2371,6 +2416,31 @@ static void d40_issue_pending(struct dma_chan *chan)
spin_unlock_irqrestore(&d40c->lock, flags);
}
static void d40_terminate_all(struct dma_chan *chan)
{
unsigned long flags;
struct d40_chan *d40c = container_of(chan, struct d40_chan, chan);
int ret;
spin_lock_irqsave(&d40c->lock, flags);
pm_runtime_get_sync(d40c->base->dev);
ret = d40_channel_execute_command(d40c, D40_DMA_STOP);
if (ret)
chan_err(d40c, "Failed to stop channel\n");
d40_term_all(d40c);
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
if (d40c->busy) {
pm_runtime_mark_last_busy(d40c->base->dev);
pm_runtime_put_autosuspend(d40c->base->dev);
}
d40c->busy = false;
spin_unlock_irqrestore(&d40c->lock, flags);
}
static int
dma40_config_to_halfchannel(struct d40_chan *d40c,
struct stedma40_half_channel_info *info,
@ -2551,7 +2621,8 @@ static int d40_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
switch (cmd) {
case DMA_TERMINATE_ALL:
return d40_terminate_all(d40c);
d40_terminate_all(chan);
return 0;
case DMA_PAUSE:
return d40_pause(d40c);
case DMA_RESUME:
@ -2908,6 +2979,12 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
dev_info(&pdev->dev, "hardware revision: %d @ 0x%x\n",
rev, res->start);
if (rev < 2) {
d40_err(&pdev->dev, "hardware revision: %d is not supported",
rev);
goto failure;
}
plat_data = pdev->dev.platform_data;
/* Count the number of logical channels in use */
@ -2998,6 +3075,7 @@ failure:
if (base) {
kfree(base->lcla_pool.alloc_map);
kfree(base->reg_val_backup_chan);
kfree(base->lookup_log_chans);
kfree(base->lookup_phy_chans);
kfree(base->phy_res);

2
drivers/dma/ste_dma40_ll.h
View File

@ -62,8 +62,6 @@
#define D40_SREG_ELEM_LOG_LIDX_MASK (0xFF << D40_SREG_ELEM_LOG_LIDX_POS)
/* Link register */
#define D40_DEACTIVATE_EVENTLINE 0x0
#define D40_ACTIVATE_EVENTLINE 0x1
#define D40_EVENTLINE_POS(i) (2 * i)
#define D40_EVENTLINE_MASK(i) (0x3 << D40_EVENTLINE_POS(i))