Re: [PATCH v4 06/11] firmware: qcom: scm: remove unused arguments to the shm_brige

Amirreza Zarrabi
2025-05-05T23:19:01Z

On 5/5/2025 8:58 PM, Kuldeep Singh wrote:
>
>
> On 4/29/2025 11:36 AM, Amirreza Zarrabi wrote:
>> shm_bridge create/delete functions always use the scm device.
>> There is no need to pass it as an argument.
>>
>> Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi@oss.qualcomm.com>
>
>
> There are 2 type of APIs exposed by tzmem driver for pool creation.
> devm_qcom_tzmem_pool_new and qcom_tzmem_pool_new.
>
> Device managed pool is created with devm_qcom_tzmem_pool_new but
> currently qcom_scm is using it's own dev to create/delete bridge which
> is problamatic here.
>
> https://elixir.bootlin.com/linux/v6.14.5/source/drivers/firmware/qcom/qcom_scm.c#L1653
>
> If pool is device managed, same dev should be used in qcom_scm to
> create/delete bridge rather than using qcom_scm dev.
> The dev passed as an argument to function should be used instead of
> __scm->dev.
> https://elixir.bootlin.com/linux/v6.14.5/source/drivers/firmware/qcom/qcom_scm.c#L1634
>
> To summarize, I believe correct solution should be to pass corresponding
> dev to bridge create/delete APIs instead of always assuming to be
> qcom_scm dev for devm_qcom_tzmem_pool_new scenarios.
> For qcom_tzmem_pool_new, qcom_scm/qcom_tzmem_dev can be used.
>
> Bartosz/Amirreza, please share your thoughts as well.
>

It is not true.
Why should shmbridge need to have access to random devices, while the resources
are obtained from the scm device, if any?

- Amir