drm/i915/chv: Don't do group access reads from TX lanes either

Like PCS, TX group reads return 0xffffffff. So we need to target each
lane separately if we want to use RMW cycles to update the registers.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 31 insertions, 18 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index d98de3c18621..f36904c14666 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2311,10 +2311,11 @@ static uint32_t intel_chv_signal_levels(struct intel_dp *intel_dp)
         struct drm_i915_private *dev_priv = dev->dev_private;
         struct intel_digital_port *dport = dp_to_dig_port(intel_dp);
         struct intel_crtc *intel_crtc = to_intel_crtc(dport->base.base.crtc);
-        u32 deemph_reg_value, margin_reg_value, val, tx_dw2;
+        u32 deemph_reg_value, margin_reg_value, val;
         uint8_t train_set = intel_dp->train_set[0];
         enum dpio_channel ch = vlv_dport_to_channel(dport);
-        int pipe = intel_crtc->pipe;
+        enum pipe pipe = intel_crtc->pipe;
+        int i;
 
         switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
         case DP_TRAIN_PRE_EMPHASIS_0:
@@ -2392,21 +2393,27 @@ static uint32_t intel_chv_signal_levels(struct intel_dp *intel_dp)
         vlv_dpio_write(dev_priv, pipe, CHV_PCS_DW10(ch), 0);
 
         /* Program swing deemph */
-        val = vlv_dpio_read(dev_priv, pipe, VLV_TX_DW4(ch));
-        val &= ~DPIO_SWING_DEEMPH9P5_MASK;
-        val |= deemph_reg_value << DPIO_SWING_DEEMPH9P5_SHIFT;
-        vlv_dpio_write(dev_priv, pipe, VLV_TX_DW4(ch), val);
+        for (i = 0; i < 4; i++) {
+                val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW4(ch, i));
+                val &= ~DPIO_SWING_DEEMPH9P5_MASK;
+                val |= deemph_reg_value << DPIO_SWING_DEEMPH9P5_SHIFT;
+                vlv_dpio_write(dev_priv, pipe, CHV_TX_DW4(ch, i), val);
+        }
 
         /* Program swing margin */
-        tx_dw2 = vlv_dpio_read(dev_priv, pipe, VLV_TX_DW2(ch));
-        tx_dw2 &= ~DPIO_SWING_MARGIN_MASK;
-        tx_dw2 |= margin_reg_value << DPIO_SWING_MARGIN_SHIFT;
-        vlv_dpio_write(dev_priv, pipe, VLV_TX_DW2(ch), tx_dw2);
+        for (i = 0; i < 4; i++) {
+                val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW2(ch, i));
+                val &= ~DPIO_SWING_MARGIN_MASK;
+                val |= margin_reg_value << DPIO_SWING_MARGIN_SHIFT;
+                vlv_dpio_write(dev_priv, pipe, CHV_TX_DW2(ch, i), val);
+        }
 
         /* Disable unique transition scale */
-        val = vlv_dpio_read(dev_priv, pipe, VLV_TX_DW3(ch));
-        val &= ~DPIO_TX_UNIQ_TRANS_SCALE_EN;
-        vlv_dpio_write(dev_priv, pipe, VLV_TX_DW3(ch), val);
+        for (i = 0; i < 4; i++) {
+                val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW3(ch, i));
+                val &= ~DPIO_TX_UNIQ_TRANS_SCALE_EN;
+                vlv_dpio_write(dev_priv, pipe, CHV_TX_DW3(ch, i), val);
+        }
 
         if (((train_set & DP_TRAIN_PRE_EMPHASIS_MASK)
                         == DP_TRAIN_PRE_EMPHASIS_0) &&
@@ -2419,12 +2426,18 @@ static uint32_t intel_chv_signal_levels(struct intel_dp *intel_dp)
                  * For now, for this unique transition scale selection, set bit
                  * 27 for ch0 and ch1.
                  */
-                val = vlv_dpio_read(dev_priv, pipe, VLV_TX_DW3(ch));
-                val |= DPIO_TX_UNIQ_TRANS_SCALE_EN;
-                vlv_dpio_write(dev_priv, pipe, VLV_TX_DW3(ch), val);
+                for (i = 0; i < 4; i++) {
+                        val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW3(ch, i));
+                        val |= DPIO_TX_UNIQ_TRANS_SCALE_EN;
+                        vlv_dpio_write(dev_priv, pipe, CHV_TX_DW3(ch, i), val);
+                }
 
-                tx_dw2 |= (0x9a << DPIO_UNIQ_TRANS_SCALE_SHIFT);
-                vlv_dpio_write(dev_priv, pipe, VLV_TX_DW2(ch), tx_dw2);
+                for (i = 0; i < 4; i++) {
+                        val = vlv_dpio_read(dev_priv, pipe, CHV_TX_DW2(ch, i));
+                        val &= ~(0xff << DPIO_UNIQ_TRANS_SCALE_SHIFT);
+                        val |= (0x9a << DPIO_UNIQ_TRANS_SCALE_SHIFT);
+                        vlv_dpio_write(dev_priv, pipe, CHV_TX_DW2(ch, i), val);
+                }
         }
 
         /* Start swing calculation */