drm/i915: set CPT FDI RX polarity bits based on VBT

Check the VBT to see if the machine has inverted FDI RX polarity on
CPT. Based on this bit, set the appropriate bit on the TRANS_CHICKEN2
registers.

This should fix some machines that were showing black screens on all
outputs.

Cc: stable@vger.kernel.org
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=60029
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 9b85fcd..d5dcf7f 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -976,6 +976,7 @@ typedef struct drm_i915_private {
        unsigned int int_crt_support:1;
        unsigned int lvds_use_ssc:1;
        unsigned int display_clock_mode:1;
+       unsigned int fdi_rx_polarity_inverted:1;
        int lvds_ssc_freq;
        unsigned int bios_lvds_val; /* initial [PCH_]LVDS reg val in VBIOS */
        struct {

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 077d40f..fc8a4a9 100644 (file)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3960,7 +3960,7 @@
 #define _TRANSB_CHICKEN2        0xf1064
 #define TRANS_CHICKEN2(pipe) _PIPE(pipe, _TRANSA_CHICKEN2, _TRANSB_CHICKEN2)
 #define  TRANS_CHICKEN2_TIMING_OVERRIDE                (1<<31)
-
+#define  TRANS_CHICKEN2_FDI_POLARITY_REVERSED  (1<<29)
 
 #define SOUTH_CHICKEN1         0xc2000
 #define  FDIA_PHASE_SYNC_SHIFT_OVR     19

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 194df27..95070b2 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -351,12 +351,14 @@ parse_general_features(struct drm_i915_private *dev_priv,
                dev_priv->lvds_ssc_freq =
                        intel_bios_ssc_frequency(dev, general->ssc_freq);
                dev_priv->display_clock_mode = general->display_clock_mode;
-               DRM_DEBUG_KMS("BDB_GENERAL_FEATURES int_tv_support %d int_crt_support %d lvds_use_ssc %d lvds_ssc_freq %d display_clock_mode %d\n",
+               dev_priv->fdi_rx_polarity_inverted = general->fdi_rx_polarity_inverted;
+               DRM_DEBUG_KMS("BDB_GENERAL_FEATURES int_tv_support %d int_crt_support %d lvds_use_ssc %d lvds_ssc_freq %d display_clock_mode %d fdi_rx_polarity_inverted %d\n",
                              dev_priv->int_tv_support,
                              dev_priv->int_crt_support,
                              dev_priv->lvds_use_ssc,
                              dev_priv->lvds_ssc_freq,
-                             dev_priv->display_clock_mode);
+                             dev_priv->display_clock_mode,
+                             dev_priv->fdi_rx_polarity_inverted);
        }
 }
 

diff --git a/drivers/gpu/drm/i915/intel_bios.h b/drivers/gpu/drm/i915/intel_bios.h
index 36e57f9..e088d6f 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.h
+++ b/drivers/gpu/drm/i915/intel_bios.h
@@ -127,7 +127,9 @@ struct bdb_general_features {
         /* bits 3 */
        u8 disable_smooth_vision:1;
        u8 single_dvi:1;
-       u8 rsvd9:6; /* finish byte */
+       u8 rsvd9:1;
+       u8 fdi_rx_polarity_inverted:1;
+       u8 rsvd10:4; /* finish byte */
 
         /* bits 4 */
        u8 legacy_monitor_detect;

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index f747cb0..6f67fa1 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3590,6 +3590,7 @@ static void cpt_init_clock_gating(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
        int pipe;
+       uint32_t val;
 
        /*
         * On Ibex Peak and Cougar Point, we need to disable clock
@@ -3602,8 +3603,12 @@ static void cpt_init_clock_gating(struct drm_device *dev)
        /* The below fixes the weird display corruption, a few pixels shifted
         * downward, on (only) LVDS of some HP laptops with IVY.
         */
-       for_each_pipe(pipe)
-               I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_CHICKEN2_TIMING_OVERRIDE);
+       for_each_pipe(pipe) {
+               val = TRANS_CHICKEN2_TIMING_OVERRIDE;
+               if (dev_priv->fdi_rx_polarity_inverted)
+                       val |= TRANS_CHICKEN2_FDI_POLARITY_REVERSED;
+               I915_WRITE(TRANS_CHICKEN2(pipe), val);
+       }
        /* WADP0ClockGatingDisable */
        for_each_pipe(pipe) {
                I915_WRITE(TRANS_CHICKEN1(pipe),