* [PATCH v2 0/2] imx-sdma: memory barrier fix
@ 2012-01-01 14:38 Richard Zhao
2012-01-01 14:38 ` [PATCH v2 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel Richard Zhao
2012-01-01 14:38 ` [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel Richard Zhao
0 siblings, 2 replies; 6+ messages in thread
From: Richard Zhao @ 2012-01-01 14:38 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel
Cc: kernel, shawn.guo, vinod.koul, dan.j.williams, eric.miao, patches
Changes in v2:
- add "let sdma_run_channel call sdma_enable_channel"
[PATCH v2 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel
[PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel
Thanks
Richard
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v2 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel
2012-01-01 14:38 [PATCH v2 0/2] imx-sdma: memory barrier fix Richard Zhao
@ 2012-01-01 14:38 ` Richard Zhao
2012-01-01 14:38 ` [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel Richard Zhao
1 sibling, 0 replies; 6+ messages in thread
From: Richard Zhao @ 2012-01-01 14:38 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel
Cc: kernel, shawn.guo, vinod.koul, dan.j.williams, eric.miao,
patches, Richard Zhao
Let all enable channel code call sdma_enable_channel.
Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
---
drivers/dma/imx-sdma.c | 12 ++++++------
1 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 2ebb2bc..f8e87b5 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -392,6 +392,11 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
return 0;
}
+static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
+{
+ __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
+}
+
/*
* sdma_run_channel - run a channel and wait till it's done
*/
@@ -403,7 +408,7 @@ static int sdma_run_channel(struct sdma_channel *sdmac)
init_completion(&sdmac->done);
- __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
+ sdma_enable_channel(sdma, channel);
ret = wait_for_completion_timeout(&sdmac->done, HZ);
@@ -807,11 +812,6 @@ out:
return ret;
}
-static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
-{
- __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
-}
-
static dma_cookie_t sdma_assign_cookie(struct sdma_channel *sdmac)
{
dma_cookie_t cookie = sdmac->chan.cookie;
--
1.7.4.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel
2012-01-01 14:38 [PATCH v2 0/2] imx-sdma: memory barrier fix Richard Zhao
2012-01-01 14:38 ` [PATCH v2 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel Richard Zhao
@ 2012-01-01 14:38 ` Richard Zhao
2012-01-03 17:46 ` Russell King - ARM Linux
1 sibling, 1 reply; 6+ messages in thread
From: Richard Zhao @ 2012-01-01 14:38 UTC (permalink / raw)
To: linux-kernel, linux-arm-kernel
Cc: kernel, shawn.guo, vinod.koul, dan.j.williams, eric.miao,
patches, Richard Zhao
dma_alloc_coherent memory may be bufferable. We need to add
nececcary memory barrier.
Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
---
drivers/dma/imx-sdma.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index f8e87b5..9301bff 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -394,6 +394,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
{
+ wmb();
__raw_writel(1 << channel, sdma->regs + SDMA_H_START);
}
--
1.7.4.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel
2012-01-01 14:38 ` [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel Richard Zhao
@ 2012-01-03 17:46 ` Russell King - ARM Linux
2012-01-04 2:31 ` Richard Zhao
0 siblings, 1 reply; 6+ messages in thread
From: Russell King - ARM Linux @ 2012-01-03 17:46 UTC (permalink / raw)
To: Richard Zhao
Cc: linux-kernel, linux-arm-kernel, patches, vinod.koul, eric.miao,
kernel, dan.j.williams, shawn.guo
On Sun, Jan 01, 2012 at 10:38:12PM +0800, Richard Zhao wrote:
> dma_alloc_coherent memory may be bufferable. We need to add
> nececcary memory barrier.
>
> Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
> ---
> drivers/dma/imx-sdma.c | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> index f8e87b5..9301bff 100644
> --- a/drivers/dma/imx-sdma.c
> +++ b/drivers/dma/imx-sdma.c
> @@ -394,6 +394,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
>
> static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
> {
> + wmb();
> __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
Use writel(). That's what it's there for:
#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
#define __iowmb() wmb()
#endif
#define writel_relaxed(v,c) ((void)__raw_writel((__force u32) \
cpu_to_le32(v),__mem_pci(c)))
#define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); })
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel
2012-01-03 17:46 ` Russell King - ARM Linux
@ 2012-01-04 2:31 ` Richard Zhao
2012-01-05 1:56 ` Richard Zhao
0 siblings, 1 reply; 6+ messages in thread
From: Richard Zhao @ 2012-01-04 2:31 UTC (permalink / raw)
To: Russell King - ARM Linux
Cc: Richard Zhao, patches, vinod.koul, linux-kernel, eric.miao,
kernel, dan.j.williams, shawn.guo, linux-arm-kernel
On Tue, Jan 03, 2012 at 05:46:39PM +0000, Russell King - ARM Linux wrote:
> On Sun, Jan 01, 2012 at 10:38:12PM +0800, Richard Zhao wrote:
> > dma_alloc_coherent memory may be bufferable. We need to add
> > nececcary memory barrier.
> >
> > Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
> > ---
> > drivers/dma/imx-sdma.c | 1 +
> > 1 files changed, 1 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> > index f8e87b5..9301bff 100644
> > --- a/drivers/dma/imx-sdma.c
> > +++ b/drivers/dma/imx-sdma.c
> > @@ -394,6 +394,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
> >
> > static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
> > {
> > + wmb();
> > __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
>
> Use writel(). That's what it's there for:
>
> #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
> #define __iowmb() wmb()
> #endif
> #define writel_relaxed(v,c) ((void)__raw_writel((__force u32) \
> cpu_to_le32(v),__mem_pci(c)))
> #define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); })
Why does writel always call wmb? ioremap memory needs mb too?
Isn't it supposed to be when there's prior touch of dma memory?
Thanks
Richard
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel
2012-01-04 2:31 ` Richard Zhao
@ 2012-01-05 1:56 ` Richard Zhao
0 siblings, 0 replies; 6+ messages in thread
From: Richard Zhao @ 2012-01-05 1:56 UTC (permalink / raw)
To: s.hauer, Russell King - ARM Linux
Cc: patches, vinod.koul, linux-kernel, eric.miao, kernel,
dan.j.williams, shawn.guo, Richard Zhao, linux-arm-kernel
Hi Sascha,
On Wed, Jan 04, 2012 at 10:31:58AM +0800, Richard Zhao wrote:
> On Tue, Jan 03, 2012 at 05:46:39PM +0000, Russell King - ARM Linux wrote:
> > On Sun, Jan 01, 2012 at 10:38:12PM +0800, Richard Zhao wrote:
> > > dma_alloc_coherent memory may be bufferable. We need to add
> > > nececcary memory barrier.
> > >
> > > Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
> > > ---
> > > drivers/dma/imx-sdma.c | 1 +
> > > 1 files changed, 1 insertions(+), 0 deletions(-)
> > >
> > > diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> > > index f8e87b5..9301bff 100644
> > > --- a/drivers/dma/imx-sdma.c
> > > +++ b/drivers/dma/imx-sdma.c
> > > @@ -394,6 +394,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
> > >
> > > static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
> > > {
> > > + wmb();
> > > __raw_writel(1 << channel, sdma->regs + SDMA_H_START);
> >
> > Use writel(). That's what it's there for:
> >
> > #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
> > #define __iowmb() wmb()
> > #endif
> > #define writel_relaxed(v,c) ((void)__raw_writel((__force u32) \
> > cpu_to_le32(v),__mem_pci(c)))
> > #define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); })
> Why does writel always call wmb? ioremap memory needs mb too?
> Isn't it supposed to be when there's prior touch of dma memory?
What do you think?
Thanks
Richard
>
> Thanks
> Richard
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> >
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-01-05 1:56 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-01-01 14:38 [PATCH v2 0/2] imx-sdma: memory barrier fix Richard Zhao
2012-01-01 14:38 ` [PATCH v2 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel Richard Zhao
2012-01-01 14:38 ` [PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel Richard Zhao
2012-01-03 17:46 ` Russell King - ARM Linux
2012-01-04 2:31 ` Richard Zhao
2012-01-05 1:56 ` Richard Zhao
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).