Re: [PATCH v3 1/2] dt-bindings: sram: Document samsung,exynos850-acpm-sram

["Alexey Klimov" <alexey.klimov@linaro.org>]

On Fri Sep 11, 2026 at 1:42 AM BST, Sam Protsenko wrote:
> On Mon, Jul 27, 2026 at 8:23 AM Alexey Klimov <alexey.klimov@linaro.org> wrote:
>>
>> Document "samsung,exynos850-acpm-sram" which represents an SRAM region used
>> for ACPM communication on Samsung-based SoCs.
>>
>> The SRAM is consumed as a whole, is not split up using child nodes and
>> properties related to this are not required.
>>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
>> Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
>> ---
>>  Documentation/devicetree/bindings/sram/sram.yaml | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/sram/sram.yaml b/Documentation/devicetree/bindings/sram/sram.yaml
>> index b83fc6831947..b9c4d4f3199b 100644
>> --- a/Documentation/devicetree/bindings/sram/sram.yaml
>> +++ b/Documentation/devicetree/bindings/sram/sram.yaml
>> @@ -43,6 +43,7 @@ properties:
>>          - qcom,rpm-msg-ram
>>          - qcom,shikra-imem
>>          - rockchip,rk3288-pmu-sram
>> +        - samsung,exynos850-acpm-sram
>
> Is there a reason we can't just use "mmio-sram" for Exynos850 ACPM
> needs? I can see it's used in the gs101 device tree like this. If
> there is a reason for this, I think it might be a good idea to
> document it in the commit message (probably in both patches).

But isn't it already in this commit message?
"The SRAM is consumed as a whole, is not split up using child nodes and
properties related to this are not required."

Also: https://lore.kernel.org/all/5797be19-8886-45a2-bfce-eb7d5f0df6c2@linaro.org/

Do you want it to be re-phrased smth like this:
"OSPM ACPM should parse the SRAM and discover essential data (e.g. queue
offsets) for establishing ACPM communication. At this point it is not
expected for any software entities apart ACPM to use SRAM so the SRAM is
consumed as a whole, is not split up using child nodes and properties
related to this are not required."

or

"The OSPM/ACPM IPC should parse the SRAM at runtime to find configuration
data (e.g., queue offsets). Because this SRAM region is dedicated
exclusively to ACPM IPC communication and is not shared with other
software entities, it is represented as a monolithic SRAM block without
requiring sub-node partitioning."

?

I hope if there will be other software entities then we will be able to
fix it later.

>Also,
> should "mmio-sram" be added as a backup option (after comma) in your
> [PATCH 2/2]?

Sure, I can add "mmio-sram".
The compatible = "rockchip,rk3288-pmu-sram", "mmio-sram"
and compatible = "qcom,rpm-msg-ram", "mmio-sram" are used in such way.

Best regards,
Alexey