Re: [PATCH 5/8] media: iris: Move vpu register defines to common header file

Konrad Dybcio
2025-09-25T09:10:20Z

On 9/25/25 1:14 AM, Vikash Garodia wrote:
> Some of vpu4 register defines are common with vpu3x. Move those into the
> common register defines header. This is done to reuse the defines for
> vpu4 in subsequent patch which enables the power sequence for vpu4.
>
> Co-developed-by: Vishnu Reddy <quic_bvisredd@quicinc.com>
> Signed-off-by: Vishnu Reddy <quic_bvisredd@quicinc.com>
> Signed-off-by: Vikash Garodia <vikash.garodia@oss.qualcomm.com>
> ---
> drivers/media/platform/qcom/iris/iris_vpu3x.c | 36 ----------------------
> drivers/media/platform/qcom/iris/iris_vpu_common.c | 23 --------------
> .../platform/qcom/iris/iris_vpu_register_defines.h | 29 +++++++++++++++++

This is a slippery slope. I think it's better if you explicitly say
the header file contains the register map of VPU3 instead, as let's say
VPU5 may add a random register in the middle (pushing some existing ones
+0x4 down). Such changes are annoying to debug, and we've unfortunately
been there on Adreno..

Because you're using this for a single common function that is both acting
upon the same registers and performing the same operations on them across
VPU35 and VPU4, it's okay to de-static-ize the function from iris_vpu3.c and
refer to it from vpu4 ops, keeping the register map private to the former
file which I think will end up less error-prone for the future.

Konrad