Re: [PATCH RFC 00/10] media: qcom: venus: add MSM8939 support

[Dmitry Baryshkov]

On Thu, Apr 16, 2026 at 04:43:47PM +0300, Erikas Bitovtas wrote:
> This patch series adds support for Venus on MSM8939. It is mostly
> similar to MSM8916 Venus, except it needs two additional cores to be
> powered on before it can start decoding.
> 
> This patch series is marked as an RFC. Before submitting a non-RFC
> series, I would like to have some details clarified regarding how Venus
> works in order to improve and eventually upstream support for MSM8939.
> 
> 1. In downstream, particularly in LA.BR.1.2.9.1_rb1.5, the buses
>    for vcodec0 cores have only decoding bits enabled, as depicted
>    by qcom,bus-configs property of qcom,msm-bus-clients children
>    in qcom,vidc node. Do I understand correctly that these cores
>    are only needed for decoding, and not for encoding?
> 2. Currently in device tree there is a video-decoder subnode for Venus
>    node, however, for SDM845-v2 (and newer) chipsets, Venus does not use
>    subnodes. Does this mean it should be dropped for MSM8939 as well?
> 3. MSM8939 supports HEVC decoding, however, as the patchset is written
>    now, it does not work. It can be enabled, however, it will result in
>    breakage of Venus for faulty MSM8916 firmwares, because the code
>    disabling HEVC for HFI v1 needs to be removed, and as per commit
>    c50cc6dc6c48 ("media: venus: hfi_parser: Ignore HEVC encoding for V1"),
>    this would break support for some MSM8916 devices. What could be the
>    best way to work around this?
> 4. To attach vcodec0 power domain list to dev_{dec,enc}, I had to move
>    vdec_get and venc_get later in the probe. Should this be avoided, and
>    is there a better way to attach vcodec power domains?
> 
> There may be some other issues with this patchset - this is WIP code, so
> feedback is very appreciated. Thank you!

for the next iteration, could you please also include fluster results
for the codecs supported by it (VP8, H.264) and also v4l2-compliance
results?

> 
> Signed-off-by: Erikas Bitovtas <xerikasxx@xxxxxxxxx>
> ---
> André Apitzsch (4):
>       media: dt-bindings: venus: Add qcom,msm8939 schema
>       media: venus: core: Add msm8939 resource struct
>       arm64: dts: qcom: msm8939: Add venus node
>       arm64: dts: qcom: msm8939-longcheer-l9100: Enable venus node
> 
> Erikas Bitovtas (6):
>       media: venus: add pmdomains to the struct based on the purpose of cores
>       arm64: dts: qcom: msm8939-asus-z00t: add Venus
>       clk: qcom: gcc-msm8939: mark Venus core GDSCs as hardware controlled
>       media: venus: move getting vdec and venc for later
>       media: qcom: venus: Move HFI v3 venc and vdec methods to HFI v1
>       media: venus: add power domain enable logic for Venus cores
> 
>  .../bindings/media/qcom,msm8939-venus.yaml         | 104 ++++++++++++
>  arch/arm64/boot/dts/qcom/msm8939-asus-z00t.dts     |   8 +
>  .../boot/dts/qcom/msm8939-longcheer-l9100.dts      |   8 +
>  arch/arm64/boot/dts/qcom/msm8939.dtsi              |  24 +++
>  drivers/clk/qcom/gcc-msm8939.c                     |   4 +
>  drivers/media/platform/qcom/venus/core.c           |  39 +++++
>  drivers/media/platform/qcom/venus/core.h           |   8 +
>  drivers/media/platform/qcom/venus/pm_helpers.c     | 187 ++++++++++++++++++---
>  drivers/media/platform/qcom/venus/vdec.c           |  12 +-
>  drivers/media/platform/qcom/venus/venc.c           |  12 +-
>  10 files changed, 374 insertions(+), 32 deletions(-)
> ---
> base-commit: 936c21068d7ade00325e40d82bfd2f3f29d9f659
> change-id: 20260416-msm8939-venus-rfc-c025c4c74fae
> 
> Best regards,
> --  
> Erikas Bitovtas <xerikasxx@xxxxxxxxx>
> 

-- 
With best wishes
Dmitry