Re: [PATCH 1/3] drm/panthor: Fix runtime suspend sequence after OPP transition error

[Liviu Dudau <liviu.dudau@arm.com>]

On Fri, Oct 11, 2024 at 11:56:59PM +0100, Adrián Larumbe wrote:
> In case an OPP transition to a suspension state fails during the runtime
> PM suspend call, if the driver's subsystems were successfully resumed,
> we should return -EAGAIN so that the device's runtime PM status remains
> 'active'.
> 
> If FW reload failed, then we should fall through, so that the PM core
> can flag the device as having suffered a runtime error.
> 
> Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com>

Acked-by: Liviu Dudau <liviu.dudau@arm.com> for this patch. For the other two
I would like first if we try to understand why the suspend does not happen
quick enough (or at all).

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_device.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c
> index 4082c8f2951d..cedd3cbcb47d 100644
> --- a/drivers/gpu/drm/panthor/panthor_device.c
> +++ b/drivers/gpu/drm/panthor/panthor_device.c
> @@ -528,8 +528,13 @@ int panthor_device_suspend(struct device *dev)
>  		    drm_dev_enter(&ptdev->base, &cookie)) {
>  			panthor_gpu_resume(ptdev);
>  			panthor_mmu_resume(ptdev);
> -			drm_WARN_ON(&ptdev->base, panthor_fw_resume(ptdev));
> -			panthor_sched_resume(ptdev);
> +			ret = panthor_fw_resume(ptdev);
> +			if (!ret) {
> +				panthor_sched_resume(ptdev);
> +				ret = -EAGAIN;
> +			} else {
> +				drm_err(&ptdev->base, "FW resume failed at runtime suspend: %d\n", ret);
> +			}
>  			drm_dev_exit(cookie);
>  		}
>  
> -- 
> 2.46.2
> 

-- 
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| but they're not |
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