[PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[bibek.patro]

From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>

The ACTLR configuration for the sa8775p MDSS client was inadvertently
dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
Add actlr settings for mdss on Qualcomm platforms"). Without this
entry, the sa8775p MDSS block does not receive the intended default
ACTLR configuration.

Restore the missing compatible entry so that the platform receives the
expected behavior.

Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
---

Hello community,

Resending this patch as the earlier version was sent as an
in‑reply‑to within an ongoing discussion thread [1], instead of being sent
as a new standalone patch submission. This may have caused it to inherit
the same message-id and appear threaded incorrectly.

Please consider this as the correct patch submission.

[1]:
https://lore.kernel.org/all/20260109204551.845959-1-bibek.patro@oss.qualcomm.com/

Thanks & regards,
Bibek

 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index 456d5146831e..718d102356d9 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -43,6 +43,8 @@ static const struct of_device_id qcom_smmu_actlr_client_of_match[] = {
 			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
 	{ .compatible = "qcom,qcm2290-mdss",
 			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
+	{ .compatible = "qcom,sa8775p-mdss",
+			.data = (const void *) (PREFETCH_DEFAULT | CMTLB) },
 	{ .compatible = "qcom,sc7280-mdss",
 			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
 	{ .compatible = "qcom,sc7280-venus",
--
2.34.1

Re: [PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[Dmitry Baryshkov]

On Tue, Jan 20, 2026 at 08:41:05PM +0530, bibek.patro@oss.qualcomm.com wrote:
> From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> 
> The ACTLR configuration for the sa8775p MDSS client was inadvertently
> dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
> Add actlr settings for mdss on Qualcomm platforms"). Without this
> entry, the sa8775p MDSS block does not receive the intended default
> ACTLR configuration.
> 
> Restore the missing compatible entry so that the platform receives the
> expected behavior.
> 
> Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>

Missing Fixes tag. Otherwise LGTM

-- 
With best wishes
Dmitry

Re: [PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[Bibek Kumar Patro]

On 1/21/2026 3:56 AM, Dmitry Baryshkov wrote:
> On Tue, Jan 20, 2026 at 08:41:05PM +0530, bibek.patro@oss.qualcomm.com wrote:
>> From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
>>
>> The ACTLR configuration for the sa8775p MDSS client was inadvertently
>> dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
>> Add actlr settings for mdss on Qualcomm platforms"). Without this
>> entry, the sa8775p MDSS block does not receive the intended default
>> ACTLR configuration.
>>
>> Restore the missing compatible entry so that the platform receives the
>> expected behavior.
>>
>> Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> 
> Missing Fixes tag. Otherwise LGTM

It looks like [1] hasn’t landed on any release branch yet - it’s still
only present in Will’s tree, which is also where the referenced “fixed
‘commit f91879fdf70b’” SHA was taken from.
Given that, do we need a Fixes: tag in this case? and should it use the
same SHA from Will’s tree.

[1]:
https://lore.kernel.org/all/176764799410.1451727.17568755330994660848.b4-ty@kernel.org/

Thanks & regards,
Bibek

> 

Re: [PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[Will Deacon]

On Thu, Jan 22, 2026 at 04:52:10PM +0530, Bibek Kumar Patro wrote:
> 
> 
> On 1/21/2026 3:56 AM, Dmitry Baryshkov wrote:
> > On Tue, Jan 20, 2026 at 08:41:05PM +0530, bibek.patro@oss.qualcomm.com wrote:
> > > From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> > > 
> > > The ACTLR configuration for the sa8775p MDSS client was inadvertently
> > > dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
> > > Add actlr settings for mdss on Qualcomm platforms"). Without this
> > > entry, the sa8775p MDSS block does not receive the intended default
> > > ACTLR configuration.
> > > 
> > > Restore the missing compatible entry so that the platform receives the
> > > expected behavior.
> > > 
> > > Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> > 
> > Missing Fixes tag. Otherwise LGTM
> 
> It looks like [1] hasn’t landed on any release branch yet - it’s still
> only present in Will’s tree, which is also where the referenced “fixed
> ‘commit f91879fdf70b’” SHA was taken from.
> Given that, do we need a Fixes: tag in this case? and should it use the
> same SHA from Will’s tree.

I'll add it when I apply, no worries. Still playing catch-up with patches
:(

Will

Re: [PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[Will Deacon]

On Tue, 20 Jan 2026 20:41:05 +0530, bibek.patro@oss.qualcomm.com wrote:
> The ACTLR configuration for the sa8775p MDSS client was inadvertently
> dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
> Add actlr settings for mdss on Qualcomm platforms"). Without this
> entry, the sa8775p MDSS block does not receive the intended default
> ACTLR configuration.
> 
> Restore the missing compatible entry so that the platform receives the
> expected behavior.
> 
> [...]

Applied to iommu (arm/smmu/updates), thanks!

[1/1] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p
      https://git.kernel.org/iommu/c/14e9a138dd02

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev

Re: [PATCH v5] iommu/arm-smmu-qcom: add actlr settings for mdss on Qualcomm platforms

[Will Deacon]

On Fri, Jan 09, 2026 at 04:59:13PM +0530, Bibek Kumar Patro wrote:
> 
> 
> On 1/6/2026 4:28 AM, Will Deacon wrote:
> > On Tue, 09 Dec 2025 10:53:23 +0530, bibek.patro@oss.qualcomm.com wrote:
> > > Add ACTLR settings for missing MDSS devices on Qualcomm platforms.
> > > 
> > > These are QoS settings and are specific to per SoC thus different
> > > settings, eg: some have shallow prefetch while others have no
> > > prefetch.
> > > 
> > > Aswell, this prefetch feature is not implemented for all the
> > > platforms, capturing to those are implemented to the best of my
> > > knowledge.
> > > 
> > > [...]
> > 
> > Applied to iommu (arm/smmu/updates), thanks!
> > 
> 
> Hi Will,
> 
> While reviewing the applied patch, I noticed that during the transition from
> v2 [1] to v3 [2], one of the SoC entries (sa8775p) appears to have been
> dropped while addressing the review comments.
> 
> Sorry for not catching this earlier.
> 
> Would it be acceptable at this stage to send a v6 including the diff below?
> Alternatively, if it’s easier on your side, please feel free to squash this
> into the existing patch currently applied in your tree.
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> index 456d5146831e..718d102356d9 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> @@ -43,6 +43,8 @@ static const struct of_device_id
> qcom_smmu_actlr_client_of_match[] = {
>                         .data = (const void *) (PREFETCH_DEEP | CPRE |
> CMTLB) },
>         { .compatible = "qcom,qcm2290-mdss",
>                         .data = (const void *) (PREFETCH_SHALLOW | CPRE |
> CMTLB) },
> +       { .compatible = "qcom,sa8775p-mdss",
> +                       .data = (const void *) (PREFETCH_DEFAULT | CMTLB) },
>         { .compatible = "qcom,sc7280-mdss",
>                         .data = (const void *) (PREFETCH_SHALLOW | CPRE |
> CMTLB) },
>         { .compatible = "qcom,sc7280-venus",
> 
> If neither approach looks suitable, I can send a standalone follow‑up patch,
> either on top of your tree[3] or on tip.

No worries, but please just send a patch on top so that we have an
explanation in the commit message and we won't have to rebase the
branch.

Cheers,

Will

[PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[bibek.patro]

From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>

The ACTLR configuration for the sa8775p MDSS client was inadvertently
dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
Add actlr settings for mdss on Qualcomm platforms"). Without this
entry, the sa8775p MDSS block does not receive the intended default
ACTLR configuration.

Restore the missing compatible entry so that the platform receives the
expected behavior.

Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
---
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index 456d5146831e..718d102356d9 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -43,6 +43,8 @@ static const struct of_device_id qcom_smmu_actlr_client_of_match[] = {
 			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
 	{ .compatible = "qcom,qcm2290-mdss",
 			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
+	{ .compatible = "qcom,sa8775p-mdss",
+			.data = (const void *) (PREFETCH_DEFAULT | CMTLB) },
 	{ .compatible = "qcom,sc7280-mdss",
 			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
 	{ .compatible = "qcom,sc7280-venus",
--
2.34.1

Re: [PATCH] iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p

[Bibek Kumar Patro]

Hi Will,

Thanks for the clarification in [1].
I’ve sent the follow‑up patch on top, including the explanation in the 
commit message as suggested.
Please lmk if any further adjustment is needed.

https://lore.kernel.org/all/aWDsFoEe7PHQaL9F@willie-the-truck/

Thanks & Regards,
Bibek

On 1/10/2026 2:15 AM, bibek.patro@oss.qualcomm.com wrote:
> From: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> 
> The ACTLR configuration for the sa8775p MDSS client was inadvertently
> dropped while reworking the commit f91879fdf70b ("iommu/arm-smmu-qcom:
> Add actlr settings for mdss on Qualcomm platforms"). Without this
> entry, the sa8775p MDSS block does not receive the intended default
> ACTLR configuration.
> 
> Restore the missing compatible entry so that the platform receives the
> expected behavior.
> 
> Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
> ---
>   drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> index 456d5146831e..718d102356d9 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
> @@ -43,6 +43,8 @@ static const struct of_device_id qcom_smmu_actlr_client_of_match[] = {
>   			.data = (const void *) (PREFETCH_DEEP | CPRE | CMTLB) },
>   	{ .compatible = "qcom,qcm2290-mdss",
>   			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
> +	{ .compatible = "qcom,sa8775p-mdss",
> +			.data = (const void *) (PREFETCH_DEFAULT | CMTLB) },
>   	{ .compatible = "qcom,sc7280-mdss",
>   			.data = (const void *) (PREFETCH_SHALLOW | CPRE | CMTLB) },
>   	{ .compatible = "qcom,sc7280-venus",
> --
> 2.34.1
>