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References: <20230628-topic-a635-v2-1-5494c881b8be@linaro.org>
In-Reply-To: <20230628-topic-a635-v2-1-5494c881b8be@linaro.org>
From:   Rob Clark <robdclark@gmail.com>
Date:   Sat, 1 Jul 2023 08:49:52 -0700
Message-ID: <CAF6AEGsH0BZd_yyn7UtJ3cLbbw2A5qdg8gQ6SORzQKjsMsnvHA@mail.gmail.com>
Subject: Re: [PATCH v2] drm/msm/adreno: Assign revn to A635
To:     Konrad Dybcio <konrad.dybcio@linaro.org>
Cc:     Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Stephen Boyd <swboyd@chromium.org>,
        Marijn Suijten <marijn.suijten@somainline.org>,
        linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org,
        freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Rob Clark <robdclark@chromium.org>
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On Fri, Jun 30, 2023 at 4:12=E2=80=AFPM Konrad Dybcio <konrad.dybcio@linaro=
.org> wrote:
>
> Recently, a WARN_ON() was introduced to ensure that revn is filled before
> adreno_is_aXYZ is called. This however doesn't work very well when revn i=
s
> 0 by design (such as for A635). Fill it in as a stopgap solution for
> -fixes.
>
> Fixes: cc943f43ece7 ("drm/msm/adreno: warn if chip revn is verified befor=
e being set")
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---
> Changes in v2:
> - add fixes
> - Link to v1: https://lore.kernel.org/r/20230628-topic-a635-v1-1-5056e09c=
08fb@linaro.org
> ---
>  drivers/gpu/drm/msm/adreno/adreno_device.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c b/drivers/gpu/drm=
/msm/adreno/adreno_device.c
> index cb94cfd137a8..8ea7eae9fc52 100644
> --- a/drivers/gpu/drm/msm/adreno/adreno_device.c
> +++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
> @@ -345,6 +345,7 @@ static const struct adreno_info gpulist[] =3D {
>                 .address_space_size =3D SZ_16G,
>         }, {
>                 .rev =3D ADRENO_REV(6, 3, 5, ANY_ID),
> +               .revn =3D 635,
>                 .fw =3D {
>                         [ADRENO_FW_SQE] =3D "a660_sqe.fw",
>                         [ADRENO_FW_GMU] =3D "a660_gmu.bin",
>

hmm, I realized a problem with this, it would change what
MSM_PARAM_GPU_ID and more importantly MSM_PARAM_CHIP_ID return..  The
former should be "harmless", although it isn't a good idea for uabi
changes to be a side effect of a fix.  The latter is more problematic.

I think I'm leaning more towards reverting commit cc943f43ece7
("drm/msm/adreno: warn if chip revn is verified before being set") for
-fixes.  I'm still thinking about options for a longer term fix.

BR,
-R


> ---
> base-commit: 5c875096d59010cee4e00da1f9c7bdb07a025dc2
> change-id: 20230628-topic-a635-1b3c2c987417
>
> Best regards,
> --
> Konrad Dybcio <konrad.dybcio@linaro.org>
>