[PATCH v4 12/15] drm/i915: prepare pipe for YCBCR output

[Shashank Sharma]

To get HDMI YCBCR420 output, the PIPEMISC register should be
programmed to:
- Generate YCBCR output (bit 11)
- In case of YCBCR420 outputs, it should be programmed in full
  blend mode to use the scaler in 5x3 ratio (bits 26 and 27)

This patch:
- Adds definition of these bits.
- Programs PIPEMISC for YCBCR outputs.

V2: rebase
V3: rebase
V4: rebase

Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
Cc: Ander Conselvan De Oliveira <ander.conselvan.de.oliveira at intel.com>
Cc: Daniel Vetter <daniel.vetter at intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h      | 3 +++
 drivers/gpu/drm/i915/intel_display.c | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 88e4707..77921ec 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5196,6 +5196,9 @@ enum {
 
 #define _PIPE_MISC_A			0x70030
 #define _PIPE_MISC_B			0x71030
+#define   PIPEMISC_YCBCR420_ENABLE	(1<<27)
+#define   PIPEMISC_YCBCR420_MODE_BLEND	(1<<26)
+#define   PIPEMISC_OUTPUT_YCBCR		(1<<11)
 #define   PIPEMISC_DITHER_BPC_MASK	(7<<5)
 #define   PIPEMISC_DITHER_8_BPC		(0<<5)
 #define   PIPEMISC_DITHER_10_BPC	(1<<5)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 983f581..71fd19e 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8109,6 +8109,15 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
 		if (intel_crtc->config->dither)
 			val |= PIPEMISC_DITHER_ENABLE | PIPEMISC_DITHER_TYPE_SP;
 
+		if (hdmi_out > DRM_HDMI_OUTPUT_DEFAULT_RGB) {
+			val |= PIPEMISC_OUTPUT_YCBCR;
+
+			if (hdmi_out == DRM_HDMI_OUTPUT_YCBCR420) {
+				val |= PIPEMISC_YCBCR420_ENABLE |
+				       PIPEMISC_YCBCR420_MODE_BLEND;
+			}
+		}
+
 		I915_WRITE(PIPEMISC(intel_crtc->pipe), val);
 	}
 }
-- 
2.7.4