Re: [PATCH v1 07/10] drm/msm/adreno: Retry on gpu resume failure

[Akhil P Oommen]

On 3/3/2022 2:51 PM, AngeloGioacchino Del Regno wrote:
> Il 02/03/22 18:27, Akhil P Oommen ha scritto:
> > Retry infinitely on resume failure because there is nothing much we can
> > do if GPU is not ON. Also, this helps us to avoid checking for the
> > return value of pm_runtime_get() to see if GPU is ON.
> >
> > Signed-off-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx>
> > ---
> >
> >   drivers/gpu/drm/msm/adreno/adreno_device.c | 10 +++++++++-
> >   1 file changed, 9 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/msm/adreno/adreno_device.c 
> > b/drivers/gpu/drm/msm/adreno/adreno_device.c
> > index 89cfd84..abcc553 100644
> > --- a/drivers/gpu/drm/msm/adreno/adreno_device.c
> > +++ b/drivers/gpu/drm/msm/adreno/adreno_device.c
> > @@ -603,8 +603,16 @@ static const struct of_device_id dt_match[] = {
> >   static int adreno_resume(struct device *dev)
> >   {
> >       struct msm_gpu *gpu = dev_to_gpu(dev);
> > +    int ret;
> > +
> > +    /* What hope do we have for the future if we can't turn ON gpu */
>
> Hello Akhil,
>
> the hope for the future would be to at least not lock up everything with
> an infinite loop, so, please change this to have a limited amount of 
> retries.
>
> My guess would be that a maximum of 10 is already a lot of retries, but
> feel free to choose an appropriate number.

Thanks for the feedback, Angelo. I will revisit this.

-Akhil.
> Regards,
> Angelo
>
> > +    while (true) {
> > +        ret = gpu->funcs->pm_resume(gpu);
> > +        if (!ret)
> > +            break;
> > +    }
> >   -    return gpu->funcs->pm_resume(gpu);
> > +    return 0;
> >   }
> >     static int active_submits(struct msm_gpu *gpu)