[Intel-gfx] [PATCH v3] drm/i915/psr: New power domain for AUX IO.

[Dhinakaran Pandiyan]

PSR on CNL requires AUX IO wells to be kept on and the existing AUX domain
for AUX-A enables DC_OFF well too. This is not required, so add a new
AUX_IO_A domain for AUX-A to allow DC states to remain enabled. Other AUX
channels re-use the existing AUX domains as they do need power well 2.

v3: Extract aux domain selection into a function (Ville)
v2: Add AUX IO domain only for AUX-A
    Rebased on top of Ville's AUX series.

Cc: Imre Deak <imre.deak at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Suggested-by: Imre Deak <imre.deak at intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
---
 drivers/gpu/drm/i915/intel_display.h    |  1 +
 drivers/gpu/drm/i915/intel_dp.c         |  2 +-
 drivers/gpu/drm/i915/intel_drv.h        |  1 +
 drivers/gpu/drm/i915/intel_psr.c        | 38 +++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_runtime_pm.c |  3 +++
 5 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.h b/drivers/gpu/drm/i915/intel_display.h
index f5733a2576e7..4e7418b345bc 100644
--- a/drivers/gpu/drm/i915/intel_display.h
+++ b/drivers/gpu/drm/i915/intel_display.h
@@ -186,6 +186,7 @@ enum intel_display_power_domain {
 	POWER_DOMAIN_AUX_C,
 	POWER_DOMAIN_AUX_D,
 	POWER_DOMAIN_AUX_F,
+	POWER_DOMAIN_AUX_IO_A,
 	POWER_DOMAIN_GMBUS,
 	POWER_DOMAIN_MODESET,
 	POWER_DOMAIN_GT_IRQ,
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 005735a7fc29..b78b9972ebae 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1331,7 +1331,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 	return ret;
 }
 
-static enum aux_ch intel_aux_ch(struct intel_dp *intel_dp)
+enum aux_ch intel_aux_ch(struct intel_dp *intel_dp)
 {
 	struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 5132f6a58c6d..bcd6dc9fb13d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1685,6 +1685,7 @@ bool intel_dp_read_dpcd(struct intel_dp *intel_dp);
 int intel_dp_link_required(int pixel_clock, int bpp);
 int intel_dp_max_data_rate(int max_link_clock, int max_lanes);
 bool intel_digital_port_connected(struct intel_encoder *encoder);
+enum aux_ch intel_aux_ch(struct intel_dp *intel_dp);
 
 /* intel_dp_aux_backlight.c */
 int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector);
diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index 2ef374f936b9..03814f7bc2d3 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -56,6 +56,40 @@
 #include "intel_drv.h"
 #include "i915_drv.h"
 
+static inline enum intel_display_power_domain
+psr_aux_domain(struct intel_dp *intel_dp)
+{
+	/* CNL HW requires corresponding AUX IOs to be powered up for PSR, AUX-A
+	 * does not require the driver to disable DC states, but the rest do.
+	 * Although PSR is enabled only on Port A currently, let's do this
+	 * correctly for other ports too.
+	 */
+	return intel_dp->aux_ch == AUX_CH_A ? POWER_DOMAIN_AUX_IO_A :
+					      intel_dp->aux_power_domain;
+}
+
+static void psr_power_get(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+	struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
+
+	if (INTEL_GEN(dev_priv) < 10)
+		return;
+
+	intel_display_power_get(dev_priv, psr_aux_domain(intel_dp));
+}
+
+static void psr_power_put(struct intel_dp *intel_dp)
+{
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+	struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
+
+	if (INTEL_GEN(dev_priv) < 10)
+		return;
+
+	intel_display_power_put(dev_priv, psr_aux_domain(intel_dp));
+}
+
 static bool vlv_is_psr_active_on_pipe(struct drm_device *dev, int pipe)
 {
 	struct drm_i915_private *dev_priv = to_i915(dev);
@@ -459,6 +493,8 @@ static void hsw_psr_enable_source(struct intel_dp *intel_dp,
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 	u32 chicken;
 
+	psr_power_get(intel_dp);
+
 	if (dev_priv->psr.psr2_support) {
 		chicken = PSR2_VSC_ENABLE_PROG_HEADER;
 		if (dev_priv->psr.y_cord_support)
@@ -617,6 +653,8 @@ static void hsw_psr_disable(struct intel_dp *intel_dp,
 		else
 			WARN_ON(I915_READ(EDP_PSR_CTL) & EDP_PSR_ENABLE);
 	}
+
+	psr_power_put(intel_dp);
 }
 
 /**
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index b7924feb9f27..53ea564f971e 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -130,6 +130,8 @@ intel_display_power_domain_str(enum intel_display_power_domain domain)
 		return "AUX_D";
 	case POWER_DOMAIN_AUX_F:
 		return "AUX_F";
+	case POWER_DOMAIN_AUX_IO_A:
+		return "AUX_IO_A";
 	case POWER_DOMAIN_GMBUS:
 		return "GMBUS";
 	case POWER_DOMAIN_INIT:
@@ -1853,6 +1855,7 @@ void intel_display_power_put(struct drm_i915_private *dev_priv,
 	BIT_ULL(POWER_DOMAIN_INIT))
 #define CNL_DISPLAY_AUX_A_POWER_DOMAINS (		\
 	BIT_ULL(POWER_DOMAIN_AUX_A) |			\
+	BIT_ULL(POWER_DOMAIN_AUX_IO_A) |		\
 	BIT_ULL(POWER_DOMAIN_INIT))
 #define CNL_DISPLAY_AUX_B_POWER_DOMAINS (		\
 	BIT_ULL(POWER_DOMAIN_AUX_B) |			\
-- 
2.14.1