[PATCH 12/20] drm/i915: prepare pipe for YCBCR420 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 YCBCR420 outputs.

V2: rebase
V3: rebase
V4: rebase
V5: added r-b from Ander
V6: Handle only YCBCR420 outputs (ville)

Reviewed-by: Ander Conselvan de Oliveira <conselvan2 at gmail.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 | 7 +++++++
 2 files changed, 10 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 64cc674..5aea2a9 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5227,6 +5227,9 @@ 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 c56081e..b4a6415 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8081,6 +8081,7 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+	struct intel_crtc_state *config = intel_crtc->config;
 
 	if (IS_BROADWELL(dev_priv) || INTEL_INFO(dev_priv)->gen >= 9) {
 		u32 val = 0;
@@ -8106,6 +8107,12 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
 		if (intel_crtc->config->dither)
 			val |= PIPEMISC_DITHER_ENABLE | PIPEMISC_DITHER_TYPE_SP;
 
+		if (config->ycbcr420) {
+			val |= PIPEMISC_OUTPUT_YCBCR |
+				PIPEMISC_YCBCR420_ENABLE |
+				PIPEMISC_YCBCR420_MODE_BLEND;
+		}
+
 		I915_WRITE(PIPEMISC(intel_crtc->pipe), val);
 	}
 }
-- 
2.7.4