drm/i915: Add some debug prints for intel_modeset_all_pipes()

Print out on which pipes, and for what reason, we are forcing a
full modeset.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220928060813.23264-1-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/intel_cdclk.c

@@ -2769,7 +2769,7 @@ int intel_modeset_calc_cdclk(struct intel_atomic_state *state)
 	} else if (intel_cdclk_needs_modeset(&old_cdclk_state->actual,
 					     &new_cdclk_state->actual)) {
 		/* All pipes must be switched off while we change the cdclk. */
-		ret = intel_modeset_all_pipes(state);
+		ret = intel_modeset_all_pipes(state, "CDCLK change");
 		if (ret)
 			return ret;
 

drivers/gpu/drm/i915/display/intel_display.c

@@ -5937,7 +5937,8 @@ intel_verify_planes(struct intel_atomic_state *state)
 			     plane_state->uapi.visible);
 }
 
-int intel_modeset_all_pipes(struct intel_atomic_state *state)
+int intel_modeset_all_pipes(struct intel_atomic_state *state,
+			    const char *reason)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
 	struct intel_crtc *crtc;
@@ -5958,6 +5959,9 @@ int intel_modeset_all_pipes(struct intel_atomic_state *state)
 		    drm_atomic_crtc_needs_modeset(&crtc_state->uapi))
 			continue;
 
+		drm_dbg_kms(&dev_priv->drm, "[CRTC:%d:%s] Full modeset due to %s\n",
+			    crtc->base.base.id, crtc->base.name, reason);
+
 		crtc_state->uapi.mode_changed = true;
 
 		ret = drm_atomic_add_affected_connectors(&state->base,

drivers/gpu/drm/i915/display/intel_display.h

@@ -683,7 +683,8 @@ void intel_modeset_driver_remove(struct drm_i915_private *i915);
 void intel_modeset_driver_remove_noirq(struct drm_i915_private *i915);
 void intel_modeset_driver_remove_nogem(struct drm_i915_private *i915);
 void intel_display_resume(struct drm_device *dev);
-int intel_modeset_all_pipes(struct intel_atomic_state *state);
+int intel_modeset_all_pipes(struct intel_atomic_state *state,
+			    const char *reason);
 void intel_modeset_get_crtc_power_domains(struct intel_crtc_state *crtc_state,
 					  struct intel_power_domain_mask *old_domains);
 void intel_modeset_put_crtc_power_domains(struct intel_crtc *crtc,

drivers/gpu/drm/i915/display/skl_watermark.c

@@ -2486,7 +2486,7 @@ skl_compute_ddb(struct intel_atomic_state *state)
 
 		if (old_dbuf_state->joined_mbus != new_dbuf_state->joined_mbus) {
 			/* TODO: Implement vblank synchronized MBUS joining changes */
-			ret = intel_modeset_all_pipes(state);
+			ret = intel_modeset_all_pipes(state, "MBUS joining change");
 			if (ret)
 				return ret;
 		}