[Intel-gfx] [PATCH v4 2/2] drm/i915: Disable PSR around cdclk changes

[Gwan-gyeong Mun]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

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 <mika.kahola at intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
Reviewed-by: Mika Kahola <mika.kahola at intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 4656a6edc3be..618a9e1e2b0c 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/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")) {
-- 
2.31.1