Re: [PATCH v2] drm/xe/pm: Handle GT resume failure

["Vivi, Rodrigo" <rodrigo.vivi@intel.com>]

On Sat, 2025-12-20 at 13:06 +0530, Raag Jadav wrote:
> We've been historically ignoring GT resume failure. Since the
> function
> can return error, handle it properly.
> 
> v2: Bring up display before bailing (Matt Roper, Rodrigo)

I'm afraid this is not exactly what we meant.

1. it is not just about display.
2. display cases might depend on gt (the chicken and egg case I had
mentioned).

It won't be a simple solution. You probably will need to experiment
with error injection cases and manual experiments before deciding
the proper approach...

> 
> Signed-off-by: Raag Jadav <raag.jadav@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_pm.c | 26 ++++++++++++++++++++++----
>  1 file changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pm.c b/drivers/gpu/drm/xe/xe_pm.c
> index 4390ba69610d..559cf5490ac0 100644
> --- a/drivers/gpu/drm/xe/xe_pm.c
> +++ b/drivers/gpu/drm/xe/xe_pm.c
> @@ -260,10 +260,19 @@ int xe_pm_resume(struct xe_device *xe)
>  
>  	xe_irq_resume(xe);
>  
> -	for_each_gt(gt, xe, id)
> -		xe_gt_resume(gt);
> +	for_each_gt(gt, xe, id) {
> +		err = xe_gt_resume(gt);
> +		if (err)
> +			break;
> +	}
>  
> +	/*
> +	 * Try to bring up display before bailing from GT resume
> failure,
> +	 * so we don't leave the user clueless with a blank screen.
> +	 */
>  	xe_display_pm_resume(xe);
> +	if (err)
> +		goto err;
>  
>  	err = xe_bo_restore_late(xe);
>  	if (err)
> @@ -656,10 +665,19 @@ int xe_pm_runtime_resume(struct xe_device *xe)
>  
>  	xe_irq_resume(xe);
>  
> -	for_each_gt(gt, xe, id)
> -		xe->d3cold.allowed ? xe_gt_resume(gt) :
> xe_gt_runtime_resume(gt);
> +	for_each_gt(gt, xe, id) {
> +		err = xe->d3cold.allowed ? xe_gt_resume(gt) :
> xe_gt_runtime_resume(gt);
> +		if (err)
> +			break;
> +	}
>  
> +	/*
> +	 * Try to bring up display before bailing from GT resume
> failure,
> +	 * so we don't leave the user clueless with a blank screen.
> +	 */
>  	xe_display_pm_runtime_resume(xe);
> +	if (err)
> +		goto out;
>  
>  	if (xe->d3cold.allowed) {
>  		err = xe_bo_restore_late(xe);