Re: [Intel-gfx] [PATCH v21 05/10] drm/i915: Extract gen specific functions from intel_can_enable_sagv

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Apr 03, 2020 at 09:20:03AM +0300, Stanislav Lisovskiy wrote:
> Addressing one of the comments, recommending to extract platform
> specific code from intel_can_enable_sagv as a preparation, before
> we are going to add support for tgl+.
> 
> Current code in intel_can_enable_sagv is valid only for skl,
> so this patch adds also proper support for icl, subsequent
> patches will add support for tgl+, combined with other required
> changes.
> 
> v2: - Renamed icl_can_enable_sagv into icl_crtc_can_enable_sagv(Ville)
>     - Removed dev variables(Ville)
>     - Constified crtc/plane_state in icl_crtc_can_enable_sagv
>       function(Ville)
>     - Added hw.active check(Ville)
>     - Refactored if ladder(Ville)
> 
> Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_pm.c | 84 +++++++++++++++++++++------------
>  1 file changed, 55 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index f8d62d1977ac..27d4d626cb34 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -3757,42 +3757,25 @@ intel_disable_sagv(struct drm_i915_private *dev_priv)
>  	return 0;
>  }
>  
> -bool intel_can_enable_sagv(struct intel_atomic_state *state)
> +static bool icl_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state)
>  {
> -	struct drm_device *dev = state->base.dev;
> -	struct drm_i915_private *dev_priv = to_i915(dev);
> -	struct intel_crtc *crtc;
> +	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
> +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
>  	struct intel_plane *plane;
> -	struct intel_crtc_state *crtc_state;
> -	enum pipe pipe;
> +	const struct intel_plane_state *plane_state;
>  	int level, latency;
>  
> -	if (!intel_has_sagv(dev_priv))
> +	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE) {
> +		DRM_DEBUG_KMS("No SAGV for interlaced mode on pipe %c\n",
> +			      pipe_name(crtc->pipe));
>  		return false;
> +	}
>  
> -	/*
> -	 * If there are no active CRTCs, no additional checks need be performed
> -	 */
> -	if (hweight8(state->active_pipes) == 0)
> +	if (!crtc_state->hw.active)

Should really be checked before anything else. Doesn't matter too much
anymore since I made us clear the crtc state always, but still a bit
inconsistent to look at other stuff in the state before we even know if
the crtc is even enabled.

>  		return true;
>  
> -	/*
> -	 * SKL+ workaround: bspec recommends we disable SAGV when we have
> -	 * more then one pipe enabled
> -	 */
> -	if (hweight8(state->active_pipes) > 1)
> -		return false;
> -
> -	/* Since we're now guaranteed to only have one active CRTC... */
> -	pipe = ffs(state->active_pipes) - 1;
> -	crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
> -	crtc_state = to_intel_crtc_state(crtc->base.state);
> -
> -	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE)
> -		return false;
> -
> -	for_each_intel_plane_on_crtc(dev, crtc, plane) {
> -		struct skl_plane_wm *wm =
> +	intel_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state) {
> +		const struct skl_plane_wm *wm =
>  			&crtc_state->wm.skl.optimal.planes[plane->id];
>  
>  		/* Skip this plane if it's not enabled */
> @@ -3807,7 +3790,7 @@ bool intel_can_enable_sagv(struct intel_atomic_state *state)
>  		latency = dev_priv->wm.skl_latency[level];
>  
>  		if (skl_needs_memory_bw_wa(dev_priv) &&
> -		    plane->base.state->fb->modifier ==
> +		    plane_state->uapi.fb->modifier ==

hw.fb

With those this is basically good, but still need to think how to avoid
the regression due to only checking the crtcs in the state.

>  		    I915_FORMAT_MOD_X_TILED)
>  			latency += 15;
>  
> @@ -3823,6 +3806,49 @@ bool intel_can_enable_sagv(struct intel_atomic_state *state)
>  	return true;
>  }
>  
> +static bool skl_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state)
> +{
> +	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
> +
> +	/*
> +	 * It has been recommended that for Gen 9 we switch SAGV off when
> +	 * multiple pipes are used.
> +	 */
> +	if (hweight8(state->active_pipes) > 1)
> +		return false;
> +
> +	/*
> +	 * Besides active pipe limitation, rest of checks pretty much match ICL
> +	 * so no need to duplicate code
> +	 */
> +	return icl_crtc_can_enable_sagv(crtc_state);
> +}
> +
> +bool intel_can_enable_sagv(struct intel_atomic_state *state)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> +	struct intel_crtc *crtc;
> +	const struct intel_crtc_state *crtc_state;
> +	int i;
> +
> +	if (!intel_has_sagv(dev_priv))
> +		return false;
> +
> +	for_each_new_intel_crtc_in_state(state, crtc, crtc_state, i) {
> +		bool can_sagv;
> +
> +		if (INTEL_GEN(dev_priv) >= 11)
> +			can_sagv = icl_crtc_can_enable_sagv(crtc_state);
> +		else
> +			can_sagv = skl_crtc_can_enable_sagv(crtc_state);
> +
> +		if (!can_sagv)
> +			return false;
> +	}
> +
> +	return true;
> +}
> +
>  /*
>   * Calculate initial DBuf slice offset, based on slice size
>   * and mask(i.e if slice size is 1024 and second slice is enabled
> -- 
> 2.24.1.485.gad05a3d8e5

-- 
Ville Syrjälä
Intel
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx