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* [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool
@ 2014-01-28 18:53 Valentine Barshak
  2014-01-29  9:07 ` Ben Dooks
  2014-01-29  9:52 ` Valentine
  0 siblings, 2 replies; 3+ messages in thread
From: Valentine Barshak @ 2014-01-28 18:53 UTC (permalink / raw)
  To: linux-sh

This increases the size of ARM coherent DMA pool to 4MB to
avoid issues with DMA bounce for PCI DMA transfers.

Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
---
 arch/arm/boot/dts/r8a7790-lager.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7790-lager.dts b/arch/arm/boot/dts/r8a7790-lager.dts
index 1081c5e..b2cac57 100644
--- a/arch/arm/boot/dts/r8a7790-lager.dts
+++ b/arch/arm/boot/dts/r8a7790-lager.dts
@@ -17,7 +17,7 @@
 	compatible = "renesas,lager", "renesas,r8a7790";
 
 	chosen {
-		bootargs = "console=ttySC6,115200 ignore_loglevel rw root=/dev/nfs ip=dhcp";
+		bootargs = "console=ttySC6,115200 ignore_loglevel rw root=/dev/nfs ip=dhcp coherent_pool=4M";
 	};
 
 	memory@40000000 {
-- 
1.8.3.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool
  2014-01-28 18:53 [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool Valentine Barshak
@ 2014-01-29  9:07 ` Ben Dooks
  2014-01-29  9:52 ` Valentine
  1 sibling, 0 replies; 3+ messages in thread
From: Ben Dooks @ 2014-01-29  9:07 UTC (permalink / raw)
  To: linux-sh

On 28/01/14 18:53, Valentine Barshak wrote:
> This increases the size of ARM coherent DMA pool to 4MB to
> avoid issues with DMA bounce for PCI DMA transfers.

Would it be easier to enable CMA support given that the DU
driver really needs it.

-- 
Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool
  2014-01-28 18:53 [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool Valentine Barshak
  2014-01-29  9:07 ` Ben Dooks
@ 2014-01-29  9:52 ` Valentine
  1 sibling, 0 replies; 3+ messages in thread
From: Valentine @ 2014-01-29  9:52 UTC (permalink / raw)
  To: linux-sh

On 01/29/2014 01:07 PM, Ben Dooks wrote:
> On 28/01/14 18:53, Valentine Barshak wrote:
>> This increases the size of ARM coherent DMA pool to 4MB to
>> avoid issues with DMA bounce for PCI DMA transfers.
>
> Would it be easier to enable CMA support given that the DU
> driver really needs it.
>

It doesn't help since dmabounce driver does not allocate bounce buffers from CMA.

Thanks,
Val.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2014-01-29  9:52 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2014-01-28 18:53 [PATCH RFC 2/2] ARM: shmobile: lager: Increase the size of ARM corehent DMA pool Valentine Barshak
2014-01-29  9:07 ` Ben Dooks
2014-01-29  9:52 ` Valentine

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