Re: [RFC PATCH] DMA: PL330: Update PL330 DMAC to support runtime PM
Russell King - ARM Linux wrote: > On Wed, Jul 27, 2011 at 03:14:27PM +0900, Chanwoo Choi wrote: >> +#ifdef CONFIG_PM_RUNTIME >> +struct dma_pl330_chan *pch; >> +struct dma_pl330_dmac *pdmac; >> +#endif >> >> dma_cap_zero(mask); >> dma_cap_set(info->cap, mask); >> >> chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch); >> >> +#ifdef CONFIG_PM_RUNTIME >> +pch = container_of(chan, struct dma_pl330_chan, chan); >> +pdmac = pch->dmac; >> + >> +pm_runtime_get_sync(pdmac->pif.dev); >> +#endif > > This is not the right way to do this. The pm runtime stuff should be > internal to the PL330 driver. Take a moment to think about this: > > You need to wake it up just before a transfer starts. You need to > put it back to sleep just after the last transfer has finished. > That gives you a hint where the calls need to be. > > That can only be done from within the PL330 driver. > Thanks for your comment&hint. I will repost the patch which support runtime pm of PL330 in internal to the PL330 driver. Regards, Chanwoo Choi -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC PATCH] DMA: PL330: Update PL330 DMAC to support runtime PM
On Wed, Jul 27, 2011 at 03:14:27PM +0900, Chanwoo Choi wrote: > +#ifdef CONFIG_PM_RUNTIME > + struct dma_pl330_chan *pch; > + struct dma_pl330_dmac *pdmac; > +#endif > > dma_cap_zero(mask); > dma_cap_set(info->cap, mask); > > chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch); > > +#ifdef CONFIG_PM_RUNTIME > + pch = container_of(chan, struct dma_pl330_chan, chan); > + pdmac = pch->dmac; > + > + pm_runtime_get_sync(pdmac->pif.dev); > +#endif This is not the right way to do this. The pm runtime stuff should be internal to the PL330 driver. Take a moment to think about this: You need to wake it up just before a transfer starts. You need to put it back to sleep just after the last transfer has finished. That gives you a hint where the calls need to be. That can only be done from within the PL330 driver. -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC PATCH] DMA: PL330: Update PL330 DMAC to support runtime PM
On Wed, Jul 27, 2011 at 11:44 AM, Chanwoo Choi wrote:
> This patch update runtime PM for PL330 DMAC to reduce power consumption.
>
> Signed-off-by: Chanwoo Choi
> Signed-off-by: Kyungmin Park
> ---
> The following patch support runtime PM for PL330 DMAC, but the clock
> of PL330 is always on. If the clock of PL330 is always on, additional power
> (10mA) is consumed.
Yes, we need to do this, but please do it in drivers/dma/pl330.c so that
every platform benefits.
> diff --git a/include/linux/amba/pl330.h b/include/linux/amba/pl330.h
> index 17b0ada..d9a63fd 100644
> --- a/include/linux/amba/pl330.h
> +++ b/include/linux/amba/pl330.h
> @@ -12,6 +12,9 @@
> #ifndef __AMBA_PL330_H_
> #define __AMBA_PL330_H_
>
> +#include
> +#include
> +
> #include
>
> struct dma_pl330_peri {
> @@ -42,4 +45,55 @@ struct dma_pl330_platdata {
> unsigned mcbuf_sz;
> };
>
> +struct dma_pl330_chan {
> + /* Schedule desc completion */
> + struct tasklet_struct task;
> +
> + /* DMA-Engine Channel */
> + struct dma_chan chan;
> +
> + /* Last completed cookie */
> + dma_cookie_t completed;
> +
> + /* List of to be xfered descriptors */
> + struct list_head work_list;
> +
> + /* Pointer to the DMAC that manages this channel,
> + * NULL if the channel is available to be acquired.
> + * As the parent, this DMAC also provides descriptors
> + * to the channel.
> + */
> + struct dma_pl330_dmac *dmac;
> +
> + /* To protect channel manipulation */
> + spinlock_t lock;
> +
> + /* Token of a hardware channel thread of PL330 DMAC
> + * NULL if the channel is available to be acquired.
> + */
> + void *pl330_chid;
> +
> + /* taks for cyclic capability */
> + struct tasklet_struct *cyclic_task;
> +
> + bool cyclic;
> +};
> +
> +struct dma_pl330_dmac {
> + struct pl330_info pif;
> +
> + /* DMA-Engine Device */
> + struct dma_device ddma;
> +
> + /* Pool of descriptors available for the DMAC's channels */
> + struct list_head desc_pool;
> + /* To protect desc_pool manipulation */
> + spinlock_t pool_lock;
> +
> + /* Peripheral channels connected to this DMAC */
> + struct dma_pl330_chan peripherals[0]; /* keep at end */
> +
> + struct clk *clk;
> +};
> +
> #endif /* __AMBA_PL330_H_ */
struct dma_pl330_dmac and struct dma_pl330_chan are internal to the
pl330 dmac driver. Nobody from outside should ever need them.
Thanks,
Jassi
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[RFC PATCH] DMA: PL330: Update PL330 DMAC to support runtime PM
This patch update runtime PM for PL330 DMAC to reduce power consumption.
Signed-off-by: Chanwoo Choi
Signed-off-by: Kyungmin Park
---
The following patch support runtime PM for PL330 DMAC, but the clock
of PL330 is always on. If the clock of PL330 is always on, additional power
(10mA) is consumed.
"[PATCH 01/15] DMA: PL330: Add support runtime PM for PL330 DMAC"
http://permalink.gmane.org/gmane.linux.kernel.samsung-soc/5931
arch/arm/plat-samsung/dma-ops.c | 21 +++
drivers/dma/pl330.c | 76 +--
include/linux/amba/pl330.h | 54 +++
3 files changed, 100 insertions(+), 51 deletions(-)
diff --git a/arch/arm/plat-samsung/dma-ops.c b/arch/arm/plat-samsung/dma-ops.c
index 9053433..b726e4a 100644
--- a/arch/arm/plat-samsung/dma-ops.c
+++ b/arch/arm/plat-samsung/dma-ops.c
@@ -13,6 +13,7 @@
#include
#include
#include
+#include
#include
@@ -33,12 +34,23 @@ static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
struct dma_chan *chan;
dma_cap_mask_t mask;
struct dma_slave_config slave_config;
+#ifdef CONFIG_PM_RUNTIME
+ struct dma_pl330_chan *pch;
+ struct dma_pl330_dmac *pdmac;
+#endif
dma_cap_zero(mask);
dma_cap_set(info->cap, mask);
chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch);
+#ifdef CONFIG_PM_RUNTIME
+ pch = container_of(chan, struct dma_pl330_chan, chan);
+ pdmac = pch->dmac;
+
+ pm_runtime_get_sync(pdmac->pif.dev);
+#endif
+
if (info->direction == DMA_FROM_DEVICE) {
memset(&slave_config, 0, sizeof(struct dma_slave_config));
slave_config.direction = info->direction;
@@ -59,8 +71,17 @@ static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
static int samsung_dmadev_release(unsigned ch,
struct s3c2410_dma_client *client)
{
+#ifdef CONFIG_PM_RUNTIME
+ struct dma_pl330_chan *pch =
+ container_of((struct dma_chan *)ch, struct dma_pl330_chan,
chan);
+ struct dma_pl330_dmac *pdmac = pdmac = pch->dmac;;
+#endif
+
dma_release_channel((struct dma_chan *)ch);
+#ifdef CONFIG_PM_RUNTIME
+ pm_runtime_put(pdmac->pif.dev);
+#endif
return 0;
}
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 121c75a..14d0ba6 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -42,57 +42,6 @@ enum desc_status {
DONE,
};
-struct dma_pl330_chan {
- /* Schedule desc completion */
- struct tasklet_struct task;
-
- /* DMA-Engine Channel */
- struct dma_chan chan;
-
- /* Last completed cookie */
- dma_cookie_t completed;
-
- /* List of to be xfered descriptors */
- struct list_head work_list;
-
- /* Pointer to the DMAC that manages this channel,
-* NULL if the channel is available to be acquired.
-* As the parent, this DMAC also provides descriptors
-* to the channel.
-*/
- struct dma_pl330_dmac *dmac;
-
- /* To protect channel manipulation */
- spinlock_t lock;
-
- /* Token of a hardware channel thread of PL330 DMAC
-* NULL if the channel is available to be acquired.
-*/
- void *pl330_chid;
-
- /* taks for cyclic capability */
- struct tasklet_struct *cyclic_task;
-
- bool cyclic;
-};
-
-struct dma_pl330_dmac {
- struct pl330_info pif;
-
- /* DMA-Engine Device */
- struct dma_device ddma;
-
- /* Pool of descriptors available for the DMAC's channels */
- struct list_head desc_pool;
- /* To protect desc_pool manipulation */
- spinlock_t pool_lock;
-
- /* Peripheral channels connected to this DMAC */
- struct dma_pl330_chan peripherals[0]; /* keep at end */
-
- struct clk *clk;
-};
-
struct dma_pl330_desc {
/* To attach to a queue as child */
struct list_head node;
@@ -935,6 +884,18 @@ pl330_probe(struct amba_device *adev, const struct amba_id
*id)
pi->pcfg.data_bus_width / 8, pi->pcfg.num_chan,
pi->pcfg.num_peri, pi->pcfg.num_events);
+#ifdef CONFIG_PM_RUNTIME
+ /* disable the power domain */
+ ret = pm_runtime_put(&adev->dev);
+ if (ret < 0) {
+ dev_err(&adev->dev, "failed to put runtime pm\n");
+ ret = -ENODEV;
+ goto probe_err4;
+ }
+#else
+ /* disable dma clk */
+ clk_disable(pdmac->clk);
+#endif
return 0;
probe_err4:
@@ -943,6 +904,13 @@ probe_err3:
free_irq(irq, pi);
probe_err2:
iounmap(pi->base);
+
+#ifdef CONFIG_PM_RUNTIME
+ pm_runtime_disable(&adev->dev);
+ pm_runtime_put(&adev->dev);
+#else
+ clk_disable(pdmac->clk);
+#endif
probe_err1:
release_mem_region(res->start, resource_size(res));
kfree(pdmac);
@@ -961,6 +929,12 @@ static int __devexit pl330_remove(struct amba_device *adev)
