[Intel-gfx] [PATCH 3/7] drm/i915: Delay between FDI link training tries. Clear FDI_RX_IIR before training

[Keith Packard]

Just a bit of cleanup; it appears to have no effect.

Signed-off-by: Keith Packard <keithp at keithp.com>
---
 drivers/gpu/drm/i915/intel_display.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7106807..95248bd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2391,6 +2391,7 @@ static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 	temp |= FDI_LINK_TRAIN_PATTERN_1;
 	I915_WRITE(reg, temp | FDI_TX_ENABLE);
 
+	I915_WRITE(FDI_RX_IIR(pipe), FDI_RX_BIT_LOCK);
 	reg = FDI_RX_CTL(pipe);
 	temp = I915_READ(reg);
 	temp &= ~FDI_LINK_TRAIN_NONE;
@@ -2398,10 +2399,10 @@ static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 	I915_WRITE(reg, temp | FDI_RX_ENABLE);
 
 	POSTING_READ(reg);
-	udelay(150);
 
 	/* Ironlake workaround, enable clock pointer after FDI enable*/
 	if (HAS_PCH_IBX(dev)) {
+		udelay(150);
 		I915_WRITE(FDI_RX_CHICKEN(pipe), FDI_RX_PHASE_SYNC_POINTER_OVR);
 		I915_WRITE(FDI_RX_CHICKEN(pipe), FDI_RX_PHASE_SYNC_POINTER_OVR |
 			   FDI_RX_PHASE_SYNC_POINTER_EN);
@@ -2409,6 +2410,7 @@ static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 
 	reg = FDI_RX_IIR(pipe);
 	for (tries = 0; tries < 5; tries++) {
+		udelay(150);
 		temp = I915_READ(reg);
 		DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
 
@@ -2422,6 +2424,7 @@ static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 		DRM_ERROR("FDI train 1 fail!\n");
 
 	/* Train 2 */
+	I915_WRITE(FDI_RX_IIR(pipe), FDI_RX_SYMBOL_LOCK);
 	reg = FDI_TX_CTL(pipe);
 	temp = I915_READ(reg);
 	temp &= ~FDI_LINK_TRAIN_NONE;
@@ -2435,10 +2438,10 @@ static void ironlake_fdi_link_train(struct drm_crtc *crtc)
 	I915_WRITE(reg, temp);
 
 	POSTING_READ(reg);
-	udelay(150);
 
 	reg = FDI_RX_IIR(pipe);
 	for (tries = 0; tries < 5; tries++) {
+		udelay(150);
 		temp = I915_READ(reg);
 		DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
 
-- 
1.7.10.4