drm/i915: Prepare to track new pipe config per pipe

Add a new_config pointer to intel_crtc which will point to the new pipe
config for said crtc while intel_crtc.config will still contain the old
config during first parts of the modeset operation. This is a step
towards having the entire new state available during the compute phase,
so that we can make accurate decisions about global resource usage.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -9225,6 +9225,7 @@ intel_modeset_update_state(struct drm_device *dev, unsigned prepare_pipes)
 	list_for_each_entry(intel_crtc, &dev->mode_config.crtc_list,
 			    base.head) {
 		WARN_ON(intel_crtc->base.enabled != intel_crtc_in_use(&intel_crtc->base));
+		WARN_ON(intel_crtc->new_config != &intel_crtc->config);
 	}
 
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
@@ -9656,6 +9657,7 @@ static int __intel_set_mode(struct drm_crtc *crtc,
 		}
 		intel_dump_pipe_config(to_intel_crtc(crtc), pipe_config,
 				       "[modeset]");
+		to_intel_crtc(crtc)->new_config = pipe_config;
 	}
 
 	/*
@@ -9689,6 +9691,7 @@ static int __intel_set_mode(struct drm_crtc *crtc,
 		/* mode_set/enable/disable functions rely on a correct pipe
 		 * config. */
 		to_intel_crtc(crtc)->config = *pipe_config;
+		to_intel_crtc(crtc)->new_config = &to_intel_crtc(crtc)->config;
 
 		/*
 		 * Calculate and store various constants which
@@ -10261,6 +10264,8 @@ static void intel_crtc_init(struct drm_device *dev, int pipe)
 	dev_priv->plane_to_crtc_mapping[intel_crtc->plane] = &intel_crtc->base;
 	dev_priv->pipe_to_crtc_mapping[intel_crtc->pipe] = &intel_crtc->base;
 
+	intel_crtc->new_config = &intel_crtc->config;
+
 	drm_crtc_helper_add(&intel_crtc->base, &intel_helper_funcs);
 }
 

drivers/gpu/drm/i915/intel_drv.h

@@ -359,6 +359,7 @@ struct intel_crtc {
 	bool cursor_visible;
 
 	struct intel_crtc_config config;
+	struct intel_crtc_config *new_config;
 	bool new_enabled;
 
 	uint32_t ddi_pll_sel;