[PATCH 06/09] drm/i915: fix Haswell M/N registers

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

We have to write the correct values inside intel_dp_set_m_n and then
we have to prevent ironlake_crtc_mode_set from overwriting the correct
values with wrong ones.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/intel_display.c |   10 ++++++----
 drivers/gpu/drm/i915/intel_dp.c      |    9 ++++++++-
 2 files changed, 14 insertions(+), 5 deletions(-)

When exactly the M/N values set inside crtc_mode_set should be used? It's
certainly not for DP...

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 1475b18..d2542bd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5018,10 +5018,12 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
 	I915_WRITE(PIPESRC(pipe),
 		   ((mode->hdisplay - 1) << 16) | (mode->vdisplay - 1));
 
-	I915_WRITE(PIPE_DATA_M1(pipe), TU_SIZE(m_n.tu) | m_n.gmch_m);
-	I915_WRITE(PIPE_DATA_N1(pipe), m_n.gmch_n);
-	I915_WRITE(PIPE_LINK_M1(pipe), m_n.link_m);
-	I915_WRITE(PIPE_LINK_N1(pipe), m_n.link_n);
+	if (!(IS_HASWELL(dev) && is_dp)) {
+		I915_WRITE(PIPE_DATA_M1(pipe), TU_SIZE(m_n.tu) | m_n.gmch_m);
+		I915_WRITE(PIPE_DATA_N1(pipe), m_n.gmch_n);
+		I915_WRITE(PIPE_LINK_M1(pipe), m_n.link_m);
+		I915_WRITE(PIPE_LINK_N1(pipe), m_n.link_n);
+	}
 
 	if (is_cpu_edp)
 		ironlake_set_pll_edp(crtc, adjusted_mode->clock);
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 2a8bf47..8c66c0c 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -795,7 +795,14 @@ intel_dp_set_m_n(struct drm_crtc *crtc, struct drm_display_mode *mode,
 	intel_dp_compute_m_n(intel_crtc->bpp, lane_count,
 			     mode->clock, adjusted_mode->clock, &m_n);
 
-	if (HAS_PCH_SPLIT(dev)) {
+	if (IS_HASWELL(dev)) {
+		I915_WRITE(PIPE_DATA_M1(pipe),
+			   ((m_n.tu - 1) << PIPE_GMCH_DATA_M_TU_SIZE_SHIFT) |
+			   m_n.gmch_m);
+		I915_WRITE(PIPE_DATA_N1(pipe), m_n.gmch_n);
+		I915_WRITE(PIPE_LINK_M1(pipe), m_n.link_m);
+		I915_WRITE(PIPE_LINK_N1(pipe), m_n.link_n);
+	} else if (HAS_PCH_SPLIT(dev)) {
 		I915_WRITE(TRANSDATA_M1(pipe),
 			   ((m_n.tu - 1) << PIPE_GMCH_DATA_M_TU_SIZE_SHIFT) |
 			   m_n.gmch_m);
-- 
1.7.10.2