[Intel-gfx] [PATCH 2/4] drm/i915: fix Haswell FDI link training code
Paulo Zanoni
przanoni at gmail.com
Thu Nov 1 21:45:05 CET 2012
From: Paulo Zanoni <paulo.r.zanoni at intel.com>
This commit makes hsw_fdi_link_train responsible for implementing
everything described in the "Enable and train FDI" section from the
Hawell CRT mode set sequence documentation. We completely rewrite
hsw_fdi_link_train to match the documentation and we also call it in
the right place.
This patch was initially sent as a series of tiny patches fixing every
little problem of the function, but since there were too many patches
fixing the same function it got a little difficult to get the "big
picture" of how the function would be in the end, so here we amended
all the patches into a single big patch fixing the whole function.
Problems we fixed:
1 - Train Haswell FDI at the right time.
We need to train the FDI before enabling the pipes and planes, so
we're moving the call from lpt_pch_enable to haswell_crtc_enable
directly.
We are also removing ironlake_fdi_pll_enable since the PLL
enablement on Haswell is completely different and is also done
during the link training steps.
2 - Use the right FDI_RX_CTL register on Haswell
There is only one PCH transcoder, so it's always _FDI_RXA_CTL.
Using "pipe" here is wrong.
3 - Don't rely on DDI_BUF_CTL previous values
Just set the bits we want, everything else is zero. Also
POSTING_READ the register before sleeping.
4 - Program the FDI RX TUSIZE register on hsw_fdi_link_train
According to the mode set sequence documentation, this is the
right place. According to the FDI_RX_TUSIZE register description,
this is the value we should set.
Also remove the code that sets this register from the old
location: lpt_pch_enable.
5 - Properly program FDI_RX_MISC pwrdn lane values on HSW
6 - Wait only 35us for the FDI link training
First we wait 30us for the FDI receiver lane calibration, then we
wait 5us for the FDI auto training time.
7 - Remove an useless indentation level on hsw_fdi_link_train
We already "break" when the link training succeeds.
8 - Disable FDI_RX_ENABLE, not FDI_RX_PLL_ENABLE
When we fail the training.
9 - Change Haswell FDI link training error messages
We shouldn't call DRM_ERROR when still looping through voltage
levels since this is expected and not really a failure. So in this
commit we adjust the error path to only DRM_ERROR when we really
fail after trying everything.
While at it, replace DRM_DEBUG_DRIVER with DRM_DEBUG_KMS since
it's what we use everywhere.
10 - Try each voltage twice at hsw_fdi_link_train
Now with Daniel Vetter's suggestion to use "/2" instead of ">>1".
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 17 ++++--
drivers/gpu/drm/i915/intel_ddi.c | 108 +++++++++++++++++++++--------------
drivers/gpu/drm/i915/intel_display.c | 11 +---
3 files changed, 76 insertions(+), 60 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index d4520d5..a167d76 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3924,16 +3924,21 @@
#define FDI_PORT_WIDTH_2X_LPT (1<<19)
#define FDI_PORT_WIDTH_1X_LPT (0<<19)
-#define _FDI_RXA_MISC 0xf0010
-#define _FDI_RXB_MISC 0xf1010
+#define _FDI_RXA_MISC 0xf0010
+#define _FDI_RXB_MISC 0xf1010
+#define FDI_RX_PWRDN_LANE1_MASK (3<<26)
+#define FDI_RX_PWRDN_LANE1_VAL(x) ((x)<<26)
+#define FDI_RX_PWRDN_LANE0_MASK (3<<24)
+#define FDI_RX_PWRDN_LANE0_VAL(x) ((x)<<24)
+#define FDI_RX_TP1_TO_TP2_48 (2<<20)
+#define FDI_RX_TP1_TO_TP2_64 (3<<20)
+#define FDI_RX_FDI_DELAY_90 (0x90<<0)
+#define FDI_RX_MISC(pipe) _PIPE(pipe, _FDI_RXA_MISC, _FDI_RXB_MISC)
+
#define _FDI_RXA_TUSIZE1 0xf0030
#define _FDI_RXA_TUSIZE2 0xf0038
#define _FDI_RXB_TUSIZE1 0xf1030
#define _FDI_RXB_TUSIZE2 0xf1038
-#define FDI_RX_TP1_TO_TP2_48 (2<<20)
-#define FDI_RX_TP1_TO_TP2_64 (3<<20)
-#define FDI_RX_FDI_DELAY_90 (0x90<<0)
-#define FDI_RX_MISC(pipe) _PIPE(pipe, _FDI_RXA_MISC, _FDI_RXB_MISC)
#define FDI_RX_TUSIZE1(pipe) _PIPE(pipe, _FDI_RXA_TUSIZE1, _FDI_RXB_TUSIZE1)
#define FDI_RX_TUSIZE2(pipe) _PIPE(pipe, _FDI_RXA_TUSIZE2, _FDI_RXB_TUSIZE2)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index a7a555f..92c2d61 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -153,11 +153,33 @@ void hsw_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);
- int pipe = intel_crtc->pipe;
- u32 reg, temp, i;
+ u32 temp, i, rx_ctl_val;
+
+ /* Set the FDI_RX_MISC pwrdn lanes and the 2 workarounds listed at the
+ * mode set "sequence for CRT port" document:
+ * - TP1 to TP2 time with the default value
+ * - FDI delay to 90h
+ */
+ I915_WRITE(_FDI_RXA_MISC, FDI_RX_PWRDN_LANE1_VAL(2) |
+ FDI_RX_PWRDN_LANE0_VAL(2) |
+ FDI_RX_TP1_TO_TP2_48 | FDI_RX_FDI_DELAY_90);
+
+ /* Enable the PCH Receiver FDI PLL */
+ rx_ctl_val = FDI_RX_PLL_ENABLE | FDI_RX_ENHANCE_FRAME_ENABLE |
+ ((intel_crtc->fdi_lanes - 1) << 19);
+ I915_WRITE(_FDI_RXA_CTL, rx_ctl_val);
+ POSTING_READ(_FDI_RXA_CTL);
+ udelay(220);
+
+ /* Switch from Rawclk to PCDclk */
+ rx_ctl_val |= FDI_PCDCLK;
+ I915_WRITE(_FDI_RXA_CTL, rx_ctl_val);
+
+ /* Configure Port Clock Select */
+ I915_WRITE(PORT_CLK_SEL(PORT_E), intel_crtc->ddi_pll_sel);
/* Start the training iterating through available voltages and emphasis */
- for (i=0; i < ARRAY_SIZE(hsw_ddi_buf_ctl_values); i++) {
+ for (i = 0; i < ARRAY_SIZE(hsw_ddi_buf_ctl_values) * 2; i++) {
/* Configure DP_TP_CTL with auto-training */
I915_WRITE(DP_TP_CTL(PORT_E),
DP_TP_CTL_FDI_AUTOTRAIN |
@@ -166,41 +188,37 @@ void hsw_fdi_link_train(struct drm_crtc *crtc)
DP_TP_CTL_ENABLE);
/* Configure and enable DDI_BUF_CTL for DDI E with next voltage */
- temp = I915_READ(DDI_BUF_CTL(PORT_E));
- temp = (temp & ~DDI_BUF_EMP_MASK);
I915_WRITE(DDI_BUF_CTL(PORT_E),
- temp |
- DDI_BUF_CTL_ENABLE |
- ((intel_crtc->fdi_lanes - 1) << 1) |
- hsw_ddi_buf_ctl_values[i]);
+ DDI_BUF_CTL_ENABLE |
+ ((intel_crtc->fdi_lanes - 1) << 1) |
+ hsw_ddi_buf_ctl_values[i / 2]);
+ POSTING_READ(DDI_BUF_CTL(PORT_E));
udelay(600);
- /* We need to program FDI_RX_MISC with the default TP1 to TP2
- * values before enabling the receiver, and configure the delay
- * for the FDI timing generator to 90h. Luckily, all the other
- * bits are supposed to be zeroed, so we can write those values
- * directly.
- */
- I915_WRITE(FDI_RX_MISC(pipe), FDI_RX_TP1_TO_TP2_48 |
- FDI_RX_FDI_DELAY_90);
-
- /* Enable CPU FDI Receiver with auto-training */
- reg = FDI_RX_CTL(pipe);
- I915_WRITE(reg,
- I915_READ(reg) |
- FDI_LINK_TRAIN_AUTO |
- FDI_RX_ENABLE |
- FDI_LINK_TRAIN_PATTERN_1_CPT |
- FDI_RX_ENHANCE_FRAME_ENABLE |
- ((intel_crtc->fdi_lanes - 1) << 19) |
- FDI_RX_PLL_ENABLE);
- POSTING_READ(reg);
- udelay(100);
+ /* Program PCH FDI Receiver TU */
+ I915_WRITE(_FDI_RXA_TUSIZE1, TU_SIZE(64));
+
+ /* Enable PCH FDI Receiver with auto-training */
+ rx_ctl_val |= FDI_RX_ENABLE | FDI_LINK_TRAIN_AUTO;
+ I915_WRITE(_FDI_RXA_CTL, rx_ctl_val);
+ POSTING_READ(_FDI_RXA_CTL);
+
+ /* Wait for FDI receiver lane calibration */
+ udelay(30);
+
+ /* Unset FDI_RX_MISC pwrdn lanes */
+ temp = I915_READ(_FDI_RXA_MISC);
+ temp &= ~(FDI_RX_PWRDN_LANE1_MASK | FDI_RX_PWRDN_LANE0_MASK);
+ I915_WRITE(_FDI_RXA_MISC, temp);
+ POSTING_READ(_FDI_RXA_MISC);
+
+ /* Wait for FDI auto training time */
+ udelay(5);
temp = I915_READ(DP_TP_STATUS(PORT_E));
if (temp & DP_TP_STATUS_AUTOTRAIN_DONE) {
- DRM_DEBUG_DRIVER("BUF_CTL training done on %d step\n", i);
+ DRM_DEBUG_KMS("FDI link training done on step %d\n", i);
/* Enable normal pixel sending for FDI */
I915_WRITE(DP_TP_CTL(PORT_E),
@@ -209,22 +227,24 @@ void hsw_fdi_link_train(struct drm_crtc *crtc)
DP_TP_CTL_ENHANCED_FRAME_ENABLE |
DP_TP_CTL_ENABLE);
- break;
- } else {
- DRM_ERROR("Error training BUF_CTL %d\n", i);
-
- /* Disable DP_TP_CTL and FDI_RX_CTL) and retry */
- I915_WRITE(DP_TP_CTL(PORT_E),
- I915_READ(DP_TP_CTL(PORT_E)) &
- ~DP_TP_CTL_ENABLE);
- I915_WRITE(FDI_RX_CTL(pipe),
- I915_READ(FDI_RX_CTL(pipe)) &
- ~FDI_RX_PLL_ENABLE);
- continue;
+ return;
}
+
+ /* Disable DP_TP_CTL and FDI_RX_CTL and retry */
+ I915_WRITE(DP_TP_CTL(PORT_E),
+ I915_READ(DP_TP_CTL(PORT_E)) & ~DP_TP_CTL_ENABLE);
+
+ rx_ctl_val &= ~FDI_RX_ENABLE;
+ I915_WRITE(_FDI_RXA_CTL, rx_ctl_val);
+
+ /* Reset FDI_RX_MISC pwrdn lanes */
+ temp = I915_READ(_FDI_RXA_MISC);
+ temp &= ~(FDI_RX_PWRDN_LANE1_MASK | FDI_RX_PWRDN_LANE0_MASK);
+ temp |= FDI_RX_PWRDN_LANE1_VAL(2) | FDI_RX_PWRDN_LANE0_VAL(2);
+ I915_WRITE(_FDI_RXA_MISC, temp);
}
- DRM_DEBUG_KMS("FDI train done.\n");
+ DRM_ERROR("FDI link training failed!\n");
}
/* WRPLL clock dividers */
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 14ea479..69ed903 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3114,9 +3114,6 @@ static void ironlake_pch_enable(struct drm_crtc *crtc)
I915_WRITE(FDI_RX_TUSIZE1(pipe),
I915_READ(PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
- /* For PCH output, training FDI link */
- dev_priv->display.fdi_link_train(crtc);
-
/* XXX: pch pll's can be enabled any time before we enable the PCH
* transcoder, and we actually should do this to not upset any PCH
* transcoder that already use the clock when we share it.
@@ -3209,16 +3206,10 @@ static void lpt_pch_enable(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);
- int pipe = intel_crtc->pipe;
enum transcoder cpu_transcoder = intel_crtc->cpu_transcoder;
assert_transcoder_disabled(dev_priv, TRANSCODER_A);
- /* Write the TU size bits before fdi link training, so that error
- * detection works. */
- I915_WRITE(FDI_RX_TUSIZE1(pipe),
- I915_READ(PIPE_DATA_M1(pipe)) & TU_SIZE_MASK);
-
/* For PCH output, training FDI link */
dev_priv->display.fdi_link_train(crtc);
@@ -3451,7 +3442,7 @@ static void haswell_crtc_enable(struct drm_crtc *crtc)
is_pch_port = haswell_crtc_driving_pch(crtc);
if (is_pch_port)
- ironlake_fdi_pll_enable(intel_crtc);
+ dev_priv->display.fdi_link_train(crtc);
for_each_encoder_on_crtc(dev, crtc, encoder)
if (encoder->pre_enable)
--
1.7.11.4
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