[PATCH 17/23] drm/i915: Do not initialize display core when display is disabled

[José Roberto de Souza]

The only thing left from *_display_core_init when display is disabled
is the skl_pch_reset_handshake() that is already handling display
enabled and disabled. And *_display_core_uninit() also was left
to disable DC.

If more power savings is required, we could disable the power wells
that BIOS enable.

Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/intel_runtime_pm.c | 32 +++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 33d7a332add4..419eae7c9ba1 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -3272,6 +3272,9 @@ static void skl_display_core_init(struct drm_i915_private *dev_priv,
 	/* enable PCH reset handshake */
 	skl_pch_reset_handshake(dev_priv);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	/* enable PG1 and Misc I/O */
 	mutex_lock(&power_domains->lock);
 
@@ -3298,6 +3301,9 @@ static void skl_display_core_uninit(struct drm_i915_private *dev_priv)
 
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	gen9_dbuf_disable(dev_priv);
 
 	skl_uninit_cdclk(dev_priv);
@@ -3337,6 +3343,9 @@ void bxt_display_core_init(struct drm_i915_private *dev_priv,
 	 */
 	skl_pch_reset_handshake(dev_priv);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	/* Enable PG1 */
 	mutex_lock(&power_domains->lock);
 
@@ -3360,6 +3369,9 @@ void bxt_display_core_uninit(struct drm_i915_private *dev_priv)
 
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	gen9_dbuf_disable(dev_priv);
 
 	bxt_uninit_cdclk(dev_priv);
@@ -3458,6 +3470,9 @@ static void cnl_display_core_init(struct drm_i915_private *dev_priv, bool resume
 	/* 1. Enable PCH Reset Handshake */
 	skl_pch_reset_handshake(dev_priv);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	/* 2. Enable Comp */
 	val = I915_READ(CHICKEN_MISC_2);
 	val &= ~CNL_COMP_PWR_DOWN;
@@ -3502,7 +3517,10 @@ static void cnl_display_core_uninit(struct drm_i915_private *dev_priv)
 
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 
-	/* 1. Disable all display engine functions -> aready done */
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
+	/* 1. Disable all display engine functions -> already done */
 
 	/* 2. Disable DBUF */
 	gen9_dbuf_disable(dev_priv);
@@ -3541,6 +3559,9 @@ static void icl_display_core_init(struct drm_i915_private *dev_priv,
 	/* 1. Enable PCH reset handshake. */
 	skl_pch_reset_handshake(dev_priv);
 
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
 	for (port = PORT_A; port <= PORT_B; port++) {
 		/* 2. Enable DDI combo PHY comp. */
 		val = I915_READ(ICL_PHY_MISC(port));
@@ -3587,7 +3608,10 @@ static void icl_display_core_uninit(struct drm_i915_private *dev_priv)
 
 	gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
 
-	/* 1. Disable all display engine functions -> aready done */
+	if (!INTEL_INFO(dev_priv)->num_pipes)
+		return;
+
+	/* 1. Disable all display engine functions -> already done */
 
 	/* 2. Disable DBUF */
 	icl_dbuf_disable(dev_priv);
@@ -3760,11 +3784,11 @@ void intel_power_domains_init_hw(struct drm_i915_private *dev_priv, bool resume)
 		skl_display_core_init(dev_priv, resume);
 	} else if (IS_GEN9_LP(dev_priv)) {
 		bxt_display_core_init(dev_priv, resume);
-	} else if (IS_CHERRYVIEW(dev_priv)) {
+	} else if (IS_CHERRYVIEW(dev_priv) && INTEL_INFO(dev_priv)->num_pipes) {
 		mutex_lock(&power_domains->lock);
 		chv_phy_control_init(dev_priv);
 		mutex_unlock(&power_domains->lock);
-	} else if (IS_VALLEYVIEW(dev_priv)) {
+	} else if (IS_VALLEYVIEW(dev_priv) && INTEL_INFO(dev_priv)->num_pipes) {
 		mutex_lock(&power_domains->lock);
 		vlv_cmnlane_wa(dev_priv);
 		mutex_unlock(&power_domains->lock);
-- 
2.19.0