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

[AngeloGioacchino Del Regno]

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.

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)