Re: [PATCH v2 1/4] dt-bindings: firmware: qcom,scm: Document that SCM can be dma-coherent

From: Konrad Dybcio
Date: Mon Jun 19 2023 - 06:00:58 EST


On 18.06.2023 10:07, Krzysztof Kozlowski wrote:
> On 16/06/2023 17:14, Douglas Anderson wrote:
>> Trogdor devices use firmware backed by TF-A instead of Qualcomm's
>> normal TZ. On TF-A we end up mapping memory as cacheable. Specifically,
>> you can see in Trogdor's TF-A code [1] in qti_sip_mem_assign() that we
>> call qti_mmap_add_dynamic_region() with MT_RO_DATA. This translates
>> down to MT_MEMORY instead of MT_NON_CACHEABLE or MT_DEVICE.
>>
>> Let's allow devices like trogdor to be described properly by allowing
>> "dma-coherent" in the SCM node.
>>
>> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx
>
> 2
Forgot to press alt or something

Konrad
>
> Best regards,
> Krzysztof
>