1 files changed, 34 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index d9bc19be855e..0b8e8eb85c19 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -355,7 +355,8 @@ intel_dp_init_panel_power_sequencer(struct drm_device *dev,
                                     struct intel_dp *intel_dp);
 static void
 intel_dp_init_panel_power_sequencer_registers(struct drm_device *dev,
-                                              struct intel_dp *intel_dp);
+                                              struct intel_dp *intel_dp,
+                                              bool force_disable_vdd);
 static void
 intel_dp_pps_init(struct drm_device *dev, struct intel_dp *intel_dp);
 
@@ -516,7 +517,7 @@ vlv_power_sequencer_pipe(struct intel_dp *intel_dp)
 
         /* init power sequencer on this pipe and port */
         intel_dp_init_panel_power_sequencer(dev, intel_dp);
-        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp);
+        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, true);
 
         /*
          * Even vdd force doesn't work until we've made
@@ -553,7 +554,7 @@ bxt_power_sequencer_idx(struct intel_dp *intel_dp)
          * Only the HW needs to be reprogrammed, the SW state is fixed and
          * has been setup during connector init.
          */
-        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp);
+        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, false);
 
         return 0;
 }
@@ -636,7 +637,7 @@ vlv_initial_power_sequencer_setup(struct intel_dp *intel_dp)
                       port_name(port), pipe_name(intel_dp->pps_pipe));
 
         intel_dp_init_panel_power_sequencer(dev, intel_dp);
-        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp);
+        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, false);
 }
 
 void intel_power_sequencer_reset(struct drm_i915_private *dev_priv)
@@ -2912,7 +2913,7 @@ static void vlv_init_panel_power_sequencer(struct intel_dp *intel_dp)
 
         /* init power sequencer on this pipe and port */
         intel_dp_init_panel_power_sequencer(dev, intel_dp);
-        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp);
+        intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, true);
 }
 
 static void vlv_pre_enable_dp(struct intel_encoder *encoder,
@@ -5055,7 +5056,8 @@ intel_dp_init_panel_power_sequencer(struct drm_device *dev,
 
 static void
 intel_dp_init_panel_power_sequencer_registers(struct drm_device *dev,
-                                              struct intel_dp *intel_dp)
+                                              struct intel_dp *intel_dp,
+                                              bool force_disable_vdd)
 {
         struct drm_i915_private *dev_priv = to_i915(dev);
         u32 pp_on, pp_off, pp_div, port_sel = 0;
@@ -5068,6 +5070,31 @@ intel_dp_init_panel_power_sequencer_registers(struct drm_device *dev,
 
         intel_pps_get_registers(dev_priv, intel_dp, &regs);
 
+        /*
+         * On some VLV machines the BIOS can leave the VDD
+         * enabled even on power seqeuencers which aren't
+         * hooked up to any port. This would mess up the
+         * power domain tracking the first time we pick
+         * one of these power sequencers for use since
+         * edp_panel_vdd_on() would notice that the VDD was
+         * already on and therefore wouldn't grab the power
+         * domain reference. Disable VDD first to avoid this.
+         * This also avoids spuriously turning the VDD on as
+         * soon as the new power seqeuencer gets initialized.
+         */
+        if (force_disable_vdd) {
+                u32 pp = ironlake_get_pp_control(intel_dp);
+
+                WARN(pp & PANEL_POWER_ON, "Panel power already on\n");
+
+                if (pp & EDP_FORCE_VDD)
+                        DRM_DEBUG_KMS("VDD already on, disabling first\n");
+
+                pp &= ~EDP_FORCE_VDD;
+
+                I915_WRITE(regs.pp_ctrl, pp);
+        }
+
         pp_on = (seq->t1_t3 << PANEL_POWER_UP_DELAY_SHIFT) |
                 (seq->t8 << PANEL_LIGHT_ON_DELAY_SHIFT);
         pp_off = (seq->t9 << PANEL_LIGHT_OFF_DELAY_SHIFT) |
@@ -5122,7 +5149,7 @@ static void intel_dp_pps_init(struct drm_device *dev,
                 vlv_initial_power_sequencer_setup(intel_dp);
         } else {
                 intel_dp_init_panel_power_sequencer(dev, intel_dp);
-                intel_dp_init_panel_power_sequencer_registers(dev, intel_dp);
+                intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, false);
         }
 }