drm/i915: Disable PSR around cdclk changes

AUX logic is often clocked from cdclk. Disable PSR to make sure
there are no hw initiated AUX transactions in flight while we
change the cdclk frequency.

Cc: Mika Kahola <[email protected]>
Signed-off-by: Ville Syrjälä <[email protected]>
Signed-off-by: Gwan-gyeong Mun <[email protected]>
Reviewed-by: Mika Kahola <[email protected]>
Signed-off-by: José Roberto de Souza <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: vsyrjala

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

@@ -28,6 +28,7 @@
 #include "intel_cdclk.h"
 #include "intel_de.h"
 #include "intel_display_types.h"
+#include "intel_psr.h"
 #include "intel_sideband.h"
 
 /**
@@ -1908,6 +1909,12 @@ static void intel_set_cdclk(struct drm_i915_private *dev_priv,
 
 	intel_dump_cdclk_config(cdclk_config, "Changing CDCLK to");
 
+	for_each_intel_encoder_with_psr(&dev_priv->drm, encoder) {
+		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+
+		intel_psr_pause(intel_dp);
+	}
+
 	/*
 	 * Lock aux/gmbus while we change cdclk in case those
 	 * functions use cdclk. Not all platforms/ports do,
@@ -1930,6 +1937,12 @@ static void intel_set_cdclk(struct drm_i915_private *dev_priv,
 	}
 	mutex_unlock(&dev_priv->gmbus_mutex);
 
+	for_each_intel_encoder_with_psr(&dev_priv->drm, encoder) {
+		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+
+		intel_psr_resume(intel_dp);
+	}
+
 	if (drm_WARN(&dev_priv->drm,
 		     intel_cdclk_changed(&dev_priv->cdclk.hw, cdclk_config),
 		     "cdclk state doesn't match!\n")) {