drm/i915: Start tracking voltage level in the cdclk state

For CNL we'll need to start considering the port clocks when we select
the voltage level for the system agent. To that end start tracking the
voltage in the cdclk state (since that already has to adjust it).

v2: s/voltage/voltage_level/ (Rodrigo)

Cc: Mika Kahola <mika.kahola@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171024095216.1638-3-ville.syrjala@linux.intel.com

5 files changed, 34 insertions, 13 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 54b5d4c..2c64c66 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2228,6 +2228,7 @@ struct i915_oa_ops {
 
 struct intel_cdclk_state {
 	unsigned int cdclk, vco, ref;
+	u8 voltage_level;
 };
 
 struct drm_i915_private {
diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c
index 4bffd31..6dad2ef 100644
--- a/drivers/gpu/drm/i915/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/intel_cdclk.c
@@ -1690,17 +1690,34 @@ void cnl_uninit_cdclk(struct drm_i915_private *dev_priv)
 }
 
 /**
- * intel_cdclk_state_compare - Determine if two CDCLK states differ
+ * intel_cdclk_needs_modeset - Determine if two CDCLK states require a modeset on all pipes
  * @a: first CDCLK state
  * @b: second CDCLK state
  *
  * Returns:
- * True if the CDCLK states are identical, false if they differ.
+ * True if the CDCLK states require pipes to be off during reprogramming, false if not.
  */
-bool intel_cdclk_state_compare(const struct intel_cdclk_state *a,
+bool intel_cdclk_needs_modeset(const struct intel_cdclk_state *a,
 			       const struct intel_cdclk_state *b)
 {
-	return memcmp(a, b, sizeof(*a)) == 0;
+	return a->cdclk != b->cdclk ||
+		a->vco != b->vco ||
+		a->ref != b->ref;
+}
+
+/**
+ * intel_cdclk_changed - Determine if two CDCLK states are different
+ * @a: first CDCLK state
+ * @b: second CDCLK state
+ *
+ * Returns:
+ * True if the CDCLK states don't match, false if they do.
+ */
+bool intel_cdclk_changed(const struct intel_cdclk_state *a,
+			 const struct intel_cdclk_state *b)
+{
+	return intel_cdclk_needs_modeset(a, b) ||
+		a->voltage_level != b->voltage_level;
 }
 
 /**
@@ -1714,15 +1731,15 @@ bool intel_cdclk_state_compare(const struct intel_cdclk_state *a,
 void intel_set_cdclk(struct drm_i915_private *dev_priv,
 		     const struct intel_cdclk_state *cdclk_state)
 {
-	if (intel_cdclk_state_compare(&dev_priv->cdclk.hw, cdclk_state))
+	if (!intel_cdclk_changed(&dev_priv->cdclk.hw, cdclk_state))
 		return;
 
 	if (WARN_ON_ONCE(!dev_priv->display.set_cdclk))
 		return;
 
-	DRM_DEBUG_DRIVER("Changing CDCLK to %d kHz, VCO %d kHz, ref %d kHz\n",
+	DRM_DEBUG_DRIVER("Changing CDCLK to %d kHz, VCO %d kHz, ref %d kHz, voltage_level %d\n",
 			 cdclk_state->cdclk, cdclk_state->vco,
-			 cdclk_state->ref);
+			 cdclk_state->ref, cdclk_state->voltage_level);
 
 	dev_priv->display.set_cdclk(dev_priv, cdclk_state);
 }
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e2ac976..1d2031a 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11931,16 +11931,16 @@ static int intel_modeset_checks(struct drm_atomic_state *state)
 		 * holding all the crtc locks, even if we don't end up
 		 * touching the hardware
 		 */
-		if (!intel_cdclk_state_compare(&dev_priv->cdclk.logical,
-					       &intel_state->cdclk.logical)) {
+		if (intel_cdclk_changed(&dev_priv->cdclk.logical,
+					&intel_state->cdclk.logical)) {
 			ret = intel_lock_all_pipes(state);
 			if (ret < 0)
 				return ret;
 		}
 
 		/* All pipes must be switched off while we change the cdclk. */
-		if (!intel_cdclk_state_compare(&dev_priv->cdclk.actual,
-					       &intel_state->cdclk.actual)) {
+		if (intel_cdclk_needs_modeset(&dev_priv->cdclk.actual,
+					      &intel_state->cdclk.actual)) {
 			ret = intel_modeset_all_pipes(state);
 			if (ret < 0)
 				return ret;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 47d022d..a551aad 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1323,8 +1323,10 @@ void intel_init_cdclk_hooks(struct drm_i915_private *dev_priv);
 void intel_update_max_cdclk(struct drm_i915_private *dev_priv);
 void intel_update_cdclk(struct drm_i915_private *dev_priv);
 void intel_update_rawclk(struct drm_i915_private *dev_priv);
-bool intel_cdclk_state_compare(const struct intel_cdclk_state *a,
+bool intel_cdclk_needs_modeset(const struct intel_cdclk_state *a,
 			       const struct intel_cdclk_state *b);
+bool intel_cdclk_changed(const struct intel_cdclk_state *a,
+			 const struct intel_cdclk_state *b);
 void intel_set_cdclk(struct drm_i915_private *dev_priv,
 		     const struct intel_cdclk_state *cdclk_state);
 
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 8af286c..8315499 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -705,7 +705,8 @@ static void gen9_dc_off_power_well_enable(struct drm_i915_private *dev_priv,
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 
 	dev_priv->display.get_cdclk(dev_priv, &cdclk_state);
-	WARN_ON(!intel_cdclk_state_compare(&dev_priv->cdclk.hw, &cdclk_state));
+	/* Can't read out voltage_level so can't use intel_cdclk_changed() */
+	WARN_ON(intel_cdclk_needs_modeset(&dev_priv->cdclk.hw, &cdclk_state));
 
 	gen9_assert_dbuf_enabled(dev_priv);