diff mbox

[2/3] ARM: qcom_defconfig: enable MSM IOMMU for display

Message ID 20171127114458.20976-3-srinivas.kandagatla@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Srinivas Kandagatla Nov. 27, 2017, 11:44 a.m. UTC 
From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

MSM IOMMU is required for apq8064 display, so enable it by default.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 arch/arm/configs/qcom_defconfig | 1 +
 1 file changed, 1 insertion(+)

Comments

J. Neuschäfer Nov. 27, 2017, 2:34 p.m. UTC | #1 
Hi,

On Mon, Nov 27, 2017 at 11:44:57AM +0000, srinivas.kandagatla@linaro.org wrote:
> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> 
> MSM IOMMU is required for apq8064 display, so enable it by default.

What exactly do you mean by "display"? Which ip block requires IOMMU
support?


Jonathan Neuschäfer
Rob Clark Nov. 27, 2017, 2:48 p.m. UTC | #2 
On Mon, Nov 27, 2017 at 9:34 AM, Jonathan Neuschäfer
<j.neuschaefer@gmx.net> wrote:
> Hi,
>
> On Mon, Nov 27, 2017 at 11:44:57AM +0000, srinivas.kandagatla@linaro.org wrote:
>> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>>
>> MSM IOMMU is required for apq8064 display, so enable it by default.
>
> What exactly do you mean by "display"? Which ip block requires IOMMU
> support?
>

display block in apq8064 is mdp4 (drivers/gpu/drm/msm/mdp/mdp4)..
technically it can use iommu in bypass mode w/ physically contiguous
memory, but no one wants to do that, if they don't have to.  The gpu
does have a hard requirement on iommu.

BR,
-R
diff mbox

Patch

diff --git a/arch/arm/configs/qcom_defconfig b/arch/arm/configs/qcom_defconfig
index 8a340c316a9a..237aa79339f6 100644
--- a/arch/arm/configs/qcom_defconfig
+++ b/arch/arm/configs/qcom_defconfig
@@ -201,6 +201,7 @@  CONFIG_MSM_LCC_8960=y
 CONFIG_MDM_LCC_9615=y
 CONFIG_MSM_MMCC_8960=y
 CONFIG_MSM_MMCC_8974=y
+CONFIG_MSM_IOMMU=y
 CONFIG_HWSPINLOCK=y
 CONFIG_HWSPINLOCK_QCOM=y
 CONFIG_REMOTEPROC=y