[Intel-gfx] [PATCH 2/4] drm/i915: Do vrr push before sampling the freame counter

[Shankar, Uma]

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Ville Syrjala
> Sent: Thursday, October 21, 2021 4:04 AM
> To: intel-gfx at lists.freedesktop.org
> Cc: Navare, Manasi D <manasi.d.navare at intel.com>
> Subject: [Intel-gfx] [PATCH 2/4] drm/i915: Do vrr push before sampling the freame
> counter

Nit: typo in frame

> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Do the vrr push before we sample the frame counter to know when the commit has
> been latched. Doing these in the wrong order could lead us to complete the flip
> before it has actually happened.
> 
> Cc: Manasi Navare <manasi.d.navare at intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_crtc.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_crtc.c
> b/drivers/gpu/drm/i915/display/intel_crtc.c
> index 254e67141a77..0f8b48b6911c 100644
> --- a/drivers/gpu/drm/i915/display/intel_crtc.c
> +++ b/drivers/gpu/drm/i915/display/intel_crtc.c
> @@ -542,6 +542,9 @@ void intel_pipe_update_end(struct intel_crtc_state
> *new_crtc_state)
> 
>  	trace_intel_pipe_update_end(crtc, end_vbl_count, scanline_end);
> 
> +	/* Send VRR Push to terminate Vblank */
> +	intel_vrr_send_push(new_crtc_state);
> +

This looks right to me.  We are at risk of arming vblank before the push,
i.e. actual vblank termination.

With the typo fixed:
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

>  	/*
>  	 * Incase of mipi dsi command mode, we need to set frame update
>  	 * request for every commit.
> @@ -568,9 +571,6 @@ void intel_pipe_update_end(struct intel_crtc_state
> *new_crtc_state)
> 
>  	local_irq_enable();
> 
> -	/* Send VRR Push to terminate Vblank */
> -	intel_vrr_send_push(new_crtc_state);
> -
>  	if (intel_vgpu_active(dev_priv))
>  		return;
> 
> --
> 2.32.0