[Intel-gfx] [PATCH 09/19] drm/i915: automatic FDI training support for Ivy Bridge
Jesse Barnes
jbarnes at virtuousgeek.org
Fri Apr 29 00:12:55 CEST 2011
Ivy Bridge supports auto-training on the CPU side, so add a separate
training function to handle it.
Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
drivers/gpu/drm/i915/i915_reg.h | 2 +
drivers/gpu/drm/i915/intel_display.c | 82 +++++++++++++++++++++++++++++++--
2 files changed, 79 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index aba3fe5..03c99ed 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3116,6 +3116,8 @@
#define FDI_LINK_TRAIN_AUTO (1<<10)
#define FDI_SCRAMBLING_ENABLE (0<<7)
#define FDI_SCRAMBLING_DISABLE (1<<7)
+/* Ivybridge */
+#define FDI_AUTO_TRAIN_DONE (1<<1)
/* FDI_RX, FDI_X is hard-wired to Transcoder_X */
#define _FDI_RXA_CTL 0xf000c
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index ab840a6..3396043 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2411,6 +2411,75 @@ static void ivb_manual_fdi_link_train(struct drm_crtc *crtc)
DRM_DEBUG_KMS("FDI train done.\n");
}
+/* On Ivybridge we can use auto training */
+static void ivb_fdi_link_train(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ unsigned long start = jiffies_to_msecs(jiffies);
+ int pipe = intel_crtc->pipe;
+ u32 reg, temp, i, j;
+
+ /* Can't pair IVB & Ibex Peak */
+ BUG_ON(HAS_PCH_IBX(dev));
+
+ reg = FDI_TX_CTL(pipe);
+ temp = I915_READ(reg);
+ temp &= ~(7 << 19);
+ temp |= (intel_crtc->fdi_lanes - 1) << 19;
+ temp &= ~FDI_LINK_TRAIN_NONE;
+ I915_WRITE(reg, temp);
+
+ /* Enable auto training on TX and RX */
+ for (i = 0; i < ARRAY_SIZE(snb_b_fdi_train_param); i++) {
+ /* Try each vswing/pre-emphasis pair twice */
+ for (j = 0; j < 2; j++) {
+ reg = FDI_TX_CTL(pipe);
+ temp = I915_READ(reg);
+ temp |= FDI_AUTO_TRAINING;
+ temp &= ~FDI_LINK_TRAIN_VOL_EMP_MASK;
+ temp |= snb_b_fdi_train_param[i];
+ I915_WRITE(reg, temp | FDI_TX_ENABLE);
+
+ reg = FDI_RX_CTL(pipe);
+ temp = I915_READ(reg);
+ I915_WRITE(reg, temp | FDI_RX_ENABLE);
+ POSTING_READ(reg);
+
+ udelay(5);
+
+ reg = FDI_TX_CTL(pipe);
+ temp = I915_READ(reg);
+ if ((temp & FDI_AUTO_TRAIN_DONE) ||
+ (I915_READ(reg) & FDI_AUTO_TRAIN_DONE)) {
+ DRM_DEBUG_KMS("FDI auto train complete in %d ms\n",
+ jiffies_to_msecs(jiffies) - start);
+ goto done;
+ }
+
+ reg = FDI_TX_CTL(pipe);
+ temp = I915_READ(reg);
+ I915_WRITE(reg, temp & ~FDI_TX_ENABLE);
+
+ reg = FDI_RX_CTL(pipe);
+ temp = I915_READ(reg);
+ I915_WRITE(reg, temp & ~FDI_RX_ENABLE);
+ POSTING_READ(reg);
+ udelay(31); /* wait idle time before retrying */
+ }
+ }
+ DRM_ERROR("FDI auto train failed\n");
+ return;
+
+done:
+ reg = FDI_RX_CTL(pipe);
+ temp = I915_READ(reg);
+ temp |= FDI_FS_ERR_CORRECT_ENABLE | FDI_FE_ERR_CORRECT_ENABLE;
+ I915_WRITE(reg, temp);
+ POSTING_READ(reg);
+}
+
static void ironlake_fdi_pll_enable(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
@@ -2452,7 +2521,7 @@ static void ironlake_fdi_pll_enable(struct drm_crtc *crtc)
}
}
-static void ironlake_fdi_disable(struct drm_crtc *crtc)
+static void ironlake_fdi_pll_disable(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -2674,9 +2743,9 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
is_pch_port = intel_crtc_driving_pch(crtc);
if (is_pch_port)
- ironlake_fdi_enable(crtc);
+ ironlake_fdi_pll_enable(crtc);
else
- ironlake_fdi_disable(crtc);
+ ironlake_fdi_pll_disable(crtc);
/* Enable panel fitting for LVDS */
if (dev_priv->pch_pf_size &&
@@ -2729,7 +2798,7 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc)
I915_WRITE(PF_CTL(pipe), 0);
I915_WRITE(PF_WIN_SZ(pipe), 0);
- ironlake_fdi_disable(crtc);
+ ironlake_fdi_pll_disable(crtc);
/* This is a horrible layering violation; we should be doing this in
* the connector/encoder ->prepare instead, but we don't always have
@@ -7418,7 +7487,10 @@ static void intel_init_display(struct drm_device *dev)
dev_priv->display.fdi_link_train = gen6_fdi_link_train;
} else if (IS_IVYBRIDGE(dev)) {
/* FIXME: detect B0+ stepping and use auto training */
- dev_priv->display.fdi_link_train = ivb_manual_fdi_link_train;
+ if (0)
+ dev_priv->display.fdi_link_train = ivb_fdi_link_train;
+ else
+ dev_priv->display.fdi_link_train = ivb_manual_fdi_link_train;
} else
dev_priv->display.update_wm = NULL;
} else if (IS_PINEVIEW(dev)) {
--
1.7.4.1
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