summaryrefslogtreecommitdiff
path: root/drivers/gpu
diff options
context:
space:
mode:
authorSean Paul <seanpaul@chromium.org>2012-03-02 17:53:39 (GMT)
committerDaniel Vetter <daniel.vetter@ffwll.ch>2012-03-02 18:39:39 (GMT)
commitfa37d39e4c6622d80bd8061d600701bcea1d6870 (patch)
tree3d7af86d6c36d375588f3b982ee05bbd3205a403 /drivers/gpu
parentb2dbf316f32b44d174445f868a39b37e4608541e (diff)
downloadlinux-fsl-qoriq-fa37d39e4c6622d80bd8061d600701bcea1d6870.tar.xz
drm/i915: Retry reading the PCH FDI receiver ISR
According to the PRM (Vol3P2), the PCH FDI receiver ISR read for bit lock should be retried at least once. This patch retries the read 5 times with a small delay in between reads. I've had reports of display corruption on resume with "FDI train 1 fail!", so I'm hoping that adding this retry will mitigate the issue. Signed-off-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/drm/i915/intel_display.c42
1 files changed, 25 insertions, 17 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index de1ba19..615b397 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2537,7 +2537,7 @@ static void gen6_fdi_link_train(struct drm_crtc *crtc)
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
int pipe = intel_crtc->pipe;
- u32 reg, temp, i;
+ u32 reg, temp, i, retry;
/* Train 1: umask FDI RX Interrupt symbol_lock and bit_lock bit
for train result */
@@ -2589,15 +2589,19 @@ static void gen6_fdi_link_train(struct drm_crtc *crtc)
POSTING_READ(reg);
udelay(500);
- reg = FDI_RX_IIR(pipe);
- temp = I915_READ(reg);
- DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
-
- if (temp & FDI_RX_BIT_LOCK) {
- I915_WRITE(reg, temp | FDI_RX_BIT_LOCK);
- DRM_DEBUG_KMS("FDI train 1 done.\n");
- break;
+ for (retry = 0; retry < 5; retry++) {
+ reg = FDI_RX_IIR(pipe);
+ temp = I915_READ(reg);
+ DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
+ if (temp & FDI_RX_BIT_LOCK) {
+ I915_WRITE(reg, temp | FDI_RX_BIT_LOCK);
+ DRM_DEBUG_KMS("FDI train 1 done.\n");
+ break;
+ }
+ udelay(50);
}
+ if (retry < 5)
+ break;
}
if (i == 4)
DRM_ERROR("FDI train 1 fail!\n");
@@ -2638,15 +2642,19 @@ static void gen6_fdi_link_train(struct drm_crtc *crtc)
POSTING_READ(reg);
udelay(500);
- reg = FDI_RX_IIR(pipe);
- temp = I915_READ(reg);
- DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
-
- if (temp & FDI_RX_SYMBOL_LOCK) {
- I915_WRITE(reg, temp | FDI_RX_SYMBOL_LOCK);
- DRM_DEBUG_KMS("FDI train 2 done.\n");
- break;
+ for (retry = 0; retry < 5; retry++) {
+ reg = FDI_RX_IIR(pipe);
+ temp = I915_READ(reg);
+ DRM_DEBUG_KMS("FDI_RX_IIR 0x%x\n", temp);
+ if (temp & FDI_RX_SYMBOL_LOCK) {
+ I915_WRITE(reg, temp | FDI_RX_SYMBOL_LOCK);
+ DRM_DEBUG_KMS("FDI train 2 done.\n");
+ break;
+ }
+ udelay(50);
}
+ if (retry < 5)
+ break;
}
if (i == 4)
DRM_ERROR("FDI train 2 fail!\n");