Re: [PATCH v4 2/2] drm/amd/display: add vendor specific reset

[Hamza Mahfooz <someguy@effective-light.com>]

On Fri, Feb 20, 2026 at 12:15:13PM -0500, Hamza Mahfooz wrote:
> We now have a means to respond to page flip timeouts. So, hook up
> support by trying to reload DMUB firmware if
> drm_atomic_helper_wait_for_flip_done() fails. Also, send out a wedged
> event if the firmware reload fails.
> 
> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com>
> ---
> v2: send a wedged event instead of attempting a GPU reset.
> v3: read return value of drm_atomic_helper_wait_for_flip_done().
> v4: only send wedged event if firmware reload fails and send out "fake"
>     page flip completes.
> ---
>  .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 24 +++++++++++++++++--
>  1 file changed, 22 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 7c51d8d7e73c..0ae6ada22fb0 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -87,6 +87,7 @@
>  #include <drm/drm_atomic_uapi.h>
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_blend.h>
> +#include <drm/drm_drv.h>
>  #include <drm/drm_fixed.h>
>  #include <drm/drm_fourcc.h>
>  #include <drm/drm_edid.h>
> @@ -10829,6 +10830,7 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
>  	struct drm_connector_state *old_con_state = NULL, *new_con_state = NULL;
>  	struct dm_crtc_state *dm_old_crtc_state, *dm_new_crtc_state;
>  	int crtc_disable_count = 0;
> +	struct amdgpu_crtc *acrtc;
>  
>  	trace_amdgpu_dm_atomic_commit_tail_begin(state);
>  
> @@ -11085,8 +11087,26 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
>  	/* Signal HW programming completion */
>  	drm_atomic_helper_commit_hw_done(state);
>  
> -	if (wait_for_vblank)
> -		drm_atomic_helper_wait_for_flip_done(dev, state);
> +	if (wait_for_vblank &&
> +	    drm_atomic_helper_wait_for_flip_done(dev, state)) {
> +		mutex_lock(&dm->dc_lock);
> +		if (dm_dmub_hw_init(adev))
> +			drm_dev_wedged_event(dev, DRM_WEDGE_RECOVERY_REBIND |
> +					     DRM_WEDGE_RECOVERY_BUS_RESET,
> +					     NULL);
> +		mutex_unlock(&dm->dc_lock);
> +
> +		spin_lock_irqsave(&dev->event_lock, flags);
> +		drm_for_each_crtc(crtc, dev) {

Whoops, sent out an older version of this patch, the following line is
here as of the latest (tested) version:

			acrtc = to_amdgpu_crtc(crtc);
> +			if (acrtc->event) {

> +				drm_crtc_send_vblank_event(crtc, acrtc->event);
> +				acrtc->event = NULL;
> +				drm_crtc_vblank_put(crtc);
> +				acrtc->pflip_status = AMDGPU_FLIP_NONE;
> +			}
> +		}
> +		spin_unlock_irqrestore(&dev->event_lock, flags);
> +	}
>  
>  	drm_atomic_helper_cleanup_planes(dev, state);
>  
> -- 
> 2.53.0
>