[Intel-gfx] [PATCH 1/2] drm/i915: Set M2_N2 registers during mode set

[Vandana Kannan]

For Gen < 8, set M2_N2 registers on every mode set. This is required to make
sure M2_N2 registers are set during boot, resume from sleep for cross-
checking the state. The register is set only if DRRS is supported.

Signed-off-by: Vandana Kannan <vandana.kannan at intel.com>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_drv.h      |  3 +++
 drivers/gpu/drm/i915/intel_display.c | 30 +++++++++++++++++++++++++++---
 drivers/gpu/drm/i915/intel_dp.c      | 14 --------------
 drivers/gpu/drm/i915/intel_drv.h     |  1 +
 4 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 6b0e174..b82f157 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1956,6 +1956,9 @@ struct drm_i915_cmd_table {
 #define HAS_PSR(dev)		(IS_HASWELL(dev) || IS_BROADWELL(dev))
 #define HAS_RUNTIME_PM(dev)	(IS_GEN6(dev) || IS_HASWELL(dev) || \
 				 IS_BROADWELL(dev) || IS_VALLEYVIEW(dev))
+#define HAS_DRRS(dev)		(to_i915(dev)->drrs.connector && \
+				 to_i915(dev)->drrs.connector-> \
+				 panel.downclock_mode)
 
 #define INTEL_PCH_DEVICE_ID_MASK		0xff00
 #define INTEL_PCH_IBX_DEVICE_ID_TYPE		0x3b00
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 767ca96..cf3ad87 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5278,6 +5278,18 @@ static void intel_dp_set_m_n(struct intel_crtc *crtc)
 		intel_cpu_transcoder_set_m_n(crtc, &crtc->config.dp_m_n);
 }
 
+void intel_dp_set_m2_n2(struct intel_crtc *crtc, struct intel_link_m_n *m_n)
+{
+	struct drm_device *dev = crtc->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	enum transcoder transcoder = crtc->config.cpu_transcoder;
+
+	I915_WRITE(PIPE_DATA_M2(transcoder), TU_SIZE(m_n->tu) | m_n->gmch_m);
+	I915_WRITE(PIPE_DATA_N2(transcoder), m_n->gmch_n);
+	I915_WRITE(PIPE_LINK_M2(transcoder), m_n->link_m);
+	I915_WRITE(PIPE_LINK_N2(transcoder), m_n->link_n);
+}
+
 static void vlv_update_pll(struct intel_crtc *crtc)
 {
 	struct drm_device *dev = crtc->base.dev;
@@ -5872,8 +5884,12 @@ skip_dpll:
 			dspcntr |= DISPPLANE_SEL_PIPE_B;
 	}
 
-	if (intel_crtc->config.has_dp_encoder)
+	if (intel_crtc->config.has_dp_encoder) {
 		intel_dp_set_m_n(intel_crtc);
+		if (INTEL_INFO(dev)->gen < 8 && HAS_DRRS(dev))
+			intel_dp_set_m2_n2(intel_crtc,
+				&intel_crtc->config.dp_m2_n2);
+	}
 
 	intel_set_pipe_timings(intel_crtc);
 
@@ -6881,8 +6897,12 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
 	} else
 		intel_put_shared_dpll(intel_crtc);
 
-	if (intel_crtc->config.has_dp_encoder)
+	if (intel_crtc->config.has_dp_encoder) {
 		intel_dp_set_m_n(intel_crtc);
+		if (INTEL_INFO(dev)->gen < 8 && HAS_DRRS(dev))
+			intel_dp_set_m2_n2(intel_crtc,
+				&intel_crtc->config.dp_m2_n2);
+	}
 
 	if (is_lvds && has_reduced_clock && i915.powersave)
 		intel_crtc->lowfreq_avail = true;
@@ -7377,8 +7397,12 @@ static int haswell_crtc_mode_set(struct drm_crtc *crtc,
 		return -EINVAL;
 	intel_ddi_pll_enable(intel_crtc);
 
-	if (intel_crtc->config.has_dp_encoder)
+	if (intel_crtc->config.has_dp_encoder) {
 		intel_dp_set_m_n(intel_crtc);
+		if (INTEL_INFO(dev)->gen < 8 && HAS_DRRS(dev))
+			intel_dp_set_m2_n2(intel_crtc,
+					&intel_crtc->config.dp_m2_n2);
+	}
 
 	intel_crtc->lowfreq_avail = false;
 
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 9f67b72..bcab4ea 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -780,20 +780,6 @@ intel_dp_set_clock(struct intel_encoder *encoder,
 	}
 }
 
-static void
-intel_dp_set_m2_n2(struct intel_crtc *crtc, struct intel_link_m_n *m_n)
-{
-	struct drm_device *dev = crtc->base.dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	enum transcoder transcoder = crtc->config.cpu_transcoder;
-
-	I915_WRITE(PIPE_DATA_M2(transcoder),
-		TU_SIZE(m_n->tu) | m_n->gmch_m);
-	I915_WRITE(PIPE_DATA_N2(transcoder), m_n->gmch_n);
-	I915_WRITE(PIPE_LINK_M2(transcoder), m_n->link_m);
-	I915_WRITE(PIPE_LINK_N2(transcoder), m_n->link_n);
-}
-
 bool
 intel_dp_compute_config(struct intel_encoder *encoder,
 			struct intel_crtc_config *pipe_config)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index acfc5c8..5233a3d 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -792,6 +792,7 @@ int valleyview_get_vco(struct drm_i915_private *dev_priv);
 void intel_mode_from_pipe_config(struct drm_display_mode *mode,
 				 struct intel_crtc_config *pipe_config);
 int intel_format_to_fourcc(int format);
+void intel_dp_set_m2_n2(struct intel_crtc *crtc, struct intel_link_m_n *m_n);
 
 /* intel_dp.c */
 void intel_dp_init(struct drm_device *dev, int output_reg, enum port port);
-- 
1.9.3