[Intel-gfx] [PATCH 3/5] drm/i915: Enable vblanks after verifying power domain states.

[Maarten Lankhorst]

Op 03-01-18 om 21:39 schreef Dhinakaran Pandiyan:
> Since we want to allow for a non-blocking power domain for vblanks,
> the power domain use count and power well use count will not be updated
> atomically inside the power domain mutex (see next patch). This affects
> verifying if sum(power_domain_use_count) == power_well_use_count at
> init time. So do not enable vblanks until this verification is done.
>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 24 ++++++++++++++++++++----
>  1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 0cd355978ab4..7bc874b8dac7 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -14739,6 +14739,24 @@ static bool has_pch_trancoder(struct drm_i915_private *dev_priv,
>  		(HAS_PCH_LPT_H(dev_priv) && pch_transcoder == PIPE_A);
>  }
>  
> +static void modeset_enable_vblanks(struct drm_i915_private *dev_priv)
> +{
> +	enum pipe pipe;
> +
> +	for_each_pipe(dev_priv, pipe) {
> +		struct intel_crtc *crtc;
> +
> +		crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
> +
> +		/* restore vblank interrupts to correct state */
> +		drm_crtc_vblank_reset(&crtc->base);
> +
> +		if (crtc->active)
> +			drm_crtc_vblank_on(&crtc->base);
> +	}
> +}
> +
> +
>  static void intel_sanitize_crtc(struct intel_crtc *crtc,
>  				struct drm_modeset_acquire_ctx *ctx)
>  {
> @@ -14754,13 +14772,9 @@ static void intel_sanitize_crtc(struct intel_crtc *crtc,
>  			   I915_READ(reg) & ~PIPECONF_FRAME_START_DELAY_MASK);
>  	}
>  
> -	/* restore vblank interrupts to correct state */
> -	drm_crtc_vblank_reset(&crtc->base);
>  	if (crtc->active) {
>  		struct intel_plane *plane;
>  
> -		drm_crtc_vblank_on(&crtc->base);
> -
>  		/* Disable everything but the primary plane */
>  		for_each_intel_plane_on_crtc(dev, crtc, plane) {
>  			const struct intel_plane_state *plane_state =
> @@ -15147,6 +15161,8 @@ intel_modeset_setup_hw_state(struct drm_device *dev,
>  
>  	intel_power_domains_verify_state(dev_priv);
>  
> +	modeset_enable_vblanks(dev_priv);
> +
>  	intel_fbc_init_pipe_state(dev_priv);
>  }
>  

intel_pre_disable_primary_noatomic calls wait_for_vblank, which will fail with this patch.
Wouldn't it be better to make intel_power_domains_verify_state work correctly with the vblank irq?

~Maarten