linux-kernel - Re: [PATCH v2 13/14] drm/msm/a6xx: Vastly increase HFI timeout

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAF6AEGsJ1WyLttZcvkgJjxsHHxX-uyz6+yb4=xizqakeZrSdTQ@mail.gmail.com>
Date:   Wed, 9 Aug 2023 15:15:17 -0700
From:   Rob Clark <robdclark@...il.com>
To:     Konrad Dybcio <konrad.dybcio@...aro.org>
Cc:     Abhinav Kumar <quic_abhinavk@...cinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@...aro.org>,
        Sean Paul <sean@...rly.run>, David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-arm-msm@...r.kernel.org, dri-devel@...ts.freedesktop.org,
        freedreno@...ts.freedesktop.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Neil Armstrong <neil.armstrong@...aro.org>
Subject: Re: [PATCH v2 13/14] drm/msm/a6xx: Vastly increase HFI timeout

On Tue, Aug 8, 2023 at 2:03 PM Konrad Dybcio <konrad.dybcio@...aro.org> wrote:
>
> A7xx GMUs can be slow as molasses at times.
> Increase the timeout to 1 second to match the vendor driver.
>
> Tested-by: Neil Armstrong <neil.armstrong@...aro.org> # on SM8550-QRD
> Tested-by: Dmitry Baryshkov <dmitry.baryshkov@...aro.org> # sm8450
> Signed-off-by: Konrad Dybcio <konrad.dybcio@...aro.org>
> ---
>  drivers/gpu/drm/msm/adreno/a6xx_hfi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_hfi.c b/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
> index cdb3f6e74d3e..e25ddb82a087 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
> @@ -108,7 +108,7 @@ static int a6xx_hfi_wait_for_ack(struct a6xx_gmu *gmu, u32 id, u32 seqnum,
>
>         /* Wait for a response */
>         ret = gmu_poll_timeout(gmu, REG_A6XX_GMU_GMU2HOST_INTR_INFO, val,
> -               val & A6XX_GMU_GMU2HOST_INTR_INFO_MSGQ, 100, 5000);
> +               val & A6XX_GMU_GMU2HOST_INTR_INFO_MSGQ, 100, 1000000);

yikes.. so our default autosuspend delay is 66ms.. and we hit this
path in the resume path (ie. if you click something after things have
been sitting idle for >66ms).. you really don't want something in that
critical path to take 1sec

BR,
-R

>
>         if (ret) {
>                 DRM_DEV_ERROR(gmu->dev,
>
> --
> 2.41.0
>