drm/i915: Reset power sequencer pipe tracking when disp2d is off

The power sequencer loses its state when the disp2d power well is down.
Clear the dev_priv->pps_pipe tracking so that the power sequencer state
gets reinitialized the next time it's needed.

v2: Fix the pps_mutex vs. power_domain mutex deadlock by taking power
    domain reference first
v3: Rename from edp_pps_(un)lock() to just pps_(un)lock() for the future,
    update due to backlight code changes

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 107 insertions, 57 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ef6a0a5088fd..83d2f76cf3e2 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -290,6 +290,38 @@ intel_dp_init_panel_power_sequencer_registers(struct drm_device *dev,
                                               struct intel_dp *intel_dp,
                                               struct edp_power_seq *out);
 
+static void pps_lock(struct intel_dp *intel_dp)
+{
+        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+        struct intel_encoder *encoder = &intel_dig_port->base;
+        struct drm_device *dev = encoder->base.dev;
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        enum intel_display_power_domain power_domain;
+
+        /*
+         * See vlv_power_sequencer_reset() why we need
+         * a power domain reference here.
+         */
+        power_domain = intel_display_port_power_domain(encoder);
+        intel_display_power_get(dev_priv, power_domain);
+
+        mutex_lock(&dev_priv->pps_mutex);
+}
+
+static void pps_unlock(struct intel_dp *intel_dp)
+{
+        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+        struct intel_encoder *encoder = &intel_dig_port->base;
+        struct drm_device *dev = encoder->base.dev;
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        enum intel_display_power_domain power_domain;
+
+        mutex_unlock(&dev_priv->pps_mutex);
+
+        power_domain = intel_display_port_power_domain(encoder);
+        intel_display_power_put(dev_priv, power_domain);
+}
+
 static enum pipe
 vlv_power_sequencer_pipe(struct intel_dp *intel_dp)
 {
@@ -391,6 +423,35 @@ vlv_initial_power_sequencer_setup(struct intel_dp *intel_dp)
                                                       &power_seq);
 }
 
+void vlv_power_sequencer_reset(struct drm_i915_private *dev_priv)
+{
+        struct drm_device *dev = dev_priv->dev;
+        struct intel_encoder *encoder;
+
+        if (WARN_ON(!IS_VALLEYVIEW(dev)))
+                return;
+
+        /*
+         * We can't grab pps_mutex here due to deadlock with power_domain
+         * mutex when power_domain functions are called while holding pps_mutex.
+         * That also means that in order to use pps_pipe the code needs to
+         * hold both a power domain reference and pps_mutex, and the power domain
+         * reference get/put must be done while _not_ holding pps_mutex.
+         * pps_{lock,unlock}() do these steps in the correct order, so one
+         * should use them always.
+         */
+
+        list_for_each_entry(encoder, &dev->mode_config.encoder_list, base.head) {
+                struct intel_dp *intel_dp;
+
+                if (encoder->type != INTEL_OUTPUT_EDP)
+                        continue;
+
+                intel_dp = enc_to_intel_dp(&encoder->base);
+                intel_dp->pps_pipe = INVALID_PIPE;
+        }
+}
+
 static u32 _pp_ctrl_reg(struct intel_dp *intel_dp)
 {
         struct drm_device *dev = intel_dp_to_dev(intel_dp);
@@ -426,7 +487,7 @@ static int edp_notify_handler(struct notifier_block *this, unsigned long code,
         if (!is_edp(intel_dp) || code != SYS_RESTART)
                 return 0;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         if (IS_VALLEYVIEW(dev)) {
                 enum pipe pipe = vlv_power_sequencer_pipe(intel_dp);
@@ -442,7 +503,7 @@ static int edp_notify_handler(struct notifier_block *this, unsigned long code,
                 msleep(intel_dp->panel_power_cycle_delay);
         }
 
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         return 0;
 }
@@ -461,15 +522,10 @@ static bool edp_have_panel_vdd(struct intel_dp *intel_dp)
 {
         struct drm_device *dev = intel_dp_to_dev(intel_dp);
         struct drm_i915_private *dev_priv = dev->dev_private;
-        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
-        struct intel_encoder *intel_encoder = &intel_dig_port->base;
-        enum intel_display_power_domain power_domain;
 
         lockdep_assert_held(&dev_priv->pps_mutex);
 
-        power_domain = intel_display_port_power_domain(intel_encoder);
-        return intel_display_power_enabled(dev_priv, power_domain) &&
-               (I915_READ(_pp_ctrl_reg(intel_dp)) & EDP_FORCE_VDD) != 0;
+        return I915_READ(_pp_ctrl_reg(intel_dp)) & EDP_FORCE_VDD;
 }
 
 static void
@@ -617,7 +673,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
         bool has_aux_irq = HAS_AUX_IRQ(dev);
         bool vdd;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         /*
          * We will be called with VDD already enabled for dpcd/edid/oui reads.
@@ -734,7 +790,7 @@ out:
         if (vdd)
                 edp_panel_vdd_off(intel_dp, false);
 
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         return ret;
 }
@@ -1315,16 +1371,14 @@ static bool edp_panel_vdd_on(struct intel_dp *intel_dp)
 
 void intel_edp_panel_vdd_on(struct intel_dp *intel_dp)
 {
-        struct drm_i915_private *dev_priv =
-                intel_dp_to_dev(intel_dp)->dev_private;
         bool vdd;
 
         if (!is_edp(intel_dp))
                 return;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         vdd = edp_panel_vdd_on(intel_dp);
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         WARN(!vdd, "eDP VDD already requested on\n");
 }
@@ -1373,13 +1427,11 @@ static void edp_panel_vdd_work(struct work_struct *__work)
 {
         struct intel_dp *intel_dp = container_of(to_delayed_work(__work),
                                                  struct intel_dp, panel_vdd_work);
-        struct drm_i915_private *dev_priv =
-                intel_dp_to_dev(intel_dp)->dev_private;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         if (!intel_dp->want_panel_vdd)
                 edp_panel_vdd_off_sync(intel_dp);
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 static void edp_panel_vdd_schedule_off(struct intel_dp *intel_dp)
@@ -1417,15 +1469,12 @@ static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)
 
 static void intel_edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)
 {
-        struct drm_i915_private *dev_priv =
-                intel_dp_to_dev(intel_dp)->dev_private;
-
         if (!is_edp(intel_dp))
                 return;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         edp_panel_vdd_off(intel_dp, sync);
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 void intel_edp_panel_on(struct intel_dp *intel_dp)
@@ -1440,7 +1489,7 @@ void intel_edp_panel_on(struct intel_dp *intel_dp)
 
         DRM_DEBUG_KMS("Turn eDP power on\n");
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         if (edp_have_panel_power(intel_dp)) {
                 DRM_DEBUG_KMS("eDP power already on\n");
@@ -1475,7 +1524,7 @@ void intel_edp_panel_on(struct intel_dp *intel_dp)
         }
 
  out:
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 void intel_edp_panel_off(struct intel_dp *intel_dp)
@@ -1493,7 +1542,7 @@ void intel_edp_panel_off(struct intel_dp *intel_dp)
 
         DRM_DEBUG_KMS("Turn eDP power off\n");
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         WARN(!intel_dp->want_panel_vdd, "Need VDD to turn off panel\n");
 
@@ -1517,7 +1566,7 @@ void intel_edp_panel_off(struct intel_dp *intel_dp)
         power_domain = intel_display_port_power_domain(intel_encoder);
         intel_display_power_put(dev_priv, power_domain);
 
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 /* Enable backlight in the panel power control. */
@@ -1537,7 +1586,7 @@ static void _intel_edp_backlight_on(struct intel_dp *intel_dp)
          */
         wait_backlight_on(intel_dp);
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         pp = ironlake_get_pp_control(intel_dp);
         pp |= EDP_BLC_ENABLE;
@@ -1547,7 +1596,7 @@ static void _intel_edp_backlight_on(struct intel_dp *intel_dp)
         I915_WRITE(pp_ctrl_reg, pp);
         POSTING_READ(pp_ctrl_reg);
 
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 /* Enable backlight PWM and backlight PP control. */
@@ -1573,7 +1622,7 @@ static void _intel_edp_backlight_off(struct intel_dp *intel_dp)
         if (!is_edp(intel_dp))
                 return;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
 
         pp = ironlake_get_pp_control(intel_dp);
         pp &= ~EDP_BLC_ENABLE;
@@ -1583,7 +1632,7 @@ static void _intel_edp_backlight_off(struct intel_dp *intel_dp)
         I915_WRITE(pp_ctrl_reg, pp);
         POSTING_READ(pp_ctrl_reg);
 
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         intel_dp->last_backlight_off = jiffies;
         edp_wait_backlight_off(intel_dp);
@@ -1608,13 +1657,12 @@ void intel_edp_backlight_off(struct intel_dp *intel_dp)
 static void intel_edp_backlight_power(struct intel_connector *connector,
                                       bool enable)
 {
-        struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
         struct intel_dp *intel_dp = intel_attached_dp(&connector->base);
         bool is_enabled;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         is_enabled = ironlake_get_pp_control(intel_dp) & EDP_BLC_ENABLE;
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         if (is_enabled == enable)
                 return;
@@ -2339,18 +2387,19 @@ static void vlv_steal_power_sequencer(struct drm_device *dev,
         list_for_each_entry(encoder, &dev->mode_config.encoder_list,
                             base.head) {
                 struct intel_dp *intel_dp;
+                enum port port;
 
                 if (encoder->type != INTEL_OUTPUT_EDP)
                         continue;
 
                 intel_dp = enc_to_intel_dp(&encoder->base);
+                port = dp_to_dig_port(intel_dp)->port;
 
                 if (intel_dp->pps_pipe != pipe)
                         continue;
 
                 DRM_DEBUG_KMS("stealing pipe %c power sequencer from port %c\n",
-                              pipe_name(pipe),
-                              port_name(dp_to_dig_port(intel_dp)->port));
+                              pipe_name(pipe), port_name(port));
 
                 /* make sure vdd is off before we steal it */
                 edp_panel_vdd_off_sync(intel_dp);
@@ -2426,9 +2475,9 @@ static void vlv_pre_enable_dp(struct intel_encoder *encoder)
         mutex_unlock(&dev_priv->dpio_lock);
 
         if (is_edp(intel_dp)) {
-                mutex_lock(&dev_priv->pps_mutex);
+                pps_lock(intel_dp);
                 vlv_init_panel_power_sequencer(intel_dp);
-                mutex_unlock(&dev_priv->pps_mutex);
+                pps_unlock(intel_dp);
         }
 
         intel_enable_dp(encoder);
@@ -2517,9 +2566,9 @@ static void chv_pre_enable_dp(struct intel_encoder *encoder)
         mutex_unlock(&dev_priv->dpio_lock);
 
         if (is_edp(intel_dp)) {
-                mutex_lock(&dev_priv->pps_mutex);
+                pps_lock(intel_dp);
                 vlv_init_panel_power_sequencer(intel_dp);
-                mutex_unlock(&dev_priv->pps_mutex);
+                pps_unlock(intel_dp);
         }
 
         intel_enable_dp(encoder);
@@ -4258,17 +4307,16 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
 {
         struct intel_digital_port *intel_dig_port = enc_to_dig_port(encoder);
         struct intel_dp *intel_dp = &intel_dig_port->dp;
-        struct drm_device *dev = intel_dp_to_dev(intel_dp);
-        struct drm_i915_private *dev_priv = dev->dev_private;
 
         drm_dp_aux_unregister(&intel_dp->aux);
         intel_dp_mst_encoder_cleanup(intel_dig_port);
         drm_encoder_cleanup(encoder);
         if (is_edp(intel_dp)) {
                 cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
-                mutex_lock(&dev_priv->pps_mutex);
+                pps_lock(intel_dp);
                 edp_panel_vdd_off_sync(intel_dp);
-                mutex_unlock(&dev_priv->pps_mutex);
+                pps_unlock(intel_dp);
+
                 if (intel_dp->edp_notifier.notifier_call) {
                         unregister_reboot_notifier(&intel_dp->edp_notifier);
                         intel_dp->edp_notifier.notifier_call = NULL;
@@ -4280,15 +4328,13 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
 static void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder)
 {
         struct intel_dp *intel_dp = enc_to_intel_dp(&intel_encoder->base);
-        struct drm_device *dev = intel_dp_to_dev(intel_dp);
-        struct drm_i915_private *dev_priv = dev->dev_private;
 
         if (!is_edp(intel_dp))
                 return;
 
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         edp_panel_vdd_off_sync(intel_dp);
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 static void intel_dp_encoder_reset(struct drm_encoder *encoder)
@@ -4767,9 +4813,10 @@ void intel_edp_panel_vdd_sanitize(struct intel_encoder *intel_encoder)
         if (intel_encoder->type != INTEL_OUTPUT_EDP)
                 return;
 
-        mutex_lock(&dev_priv->pps_mutex);
-
         intel_dp = enc_to_intel_dp(&intel_encoder->base);
+
+        pps_lock(intel_dp);
+
         if (!edp_have_panel_vdd(intel_dp))
                 goto out;
         /*
@@ -4784,7 +4831,7 @@ void intel_edp_panel_vdd_sanitize(struct intel_encoder *intel_encoder)
 
         edp_panel_vdd_schedule_off(intel_dp);
  out:
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 }
 
 static bool intel_edp_init_connector(struct intel_dp *intel_dp,
@@ -4826,9 +4873,9 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
         }
 
         /* We now know it's not a ghost, init power sequence regs. */
-        mutex_lock(&dev_priv->pps_mutex);
+        pps_lock(intel_dp);
         intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, power_seq);
-        mutex_unlock(&dev_priv->pps_mutex);
+        pps_unlock(intel_dp);
 
         mutex_lock(&dev->mode_config.mutex);
         edid = drm_get_edid(connector, &intel_dp->aux.ddc);
@@ -4963,7 +5010,7 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
         }
 
         if (is_edp(intel_dp)) {
-                mutex_lock(&dev_priv->pps_mutex);
+                pps_lock(intel_dp);
                 if (IS_VALLEYVIEW(dev)) {
                         vlv_initial_power_sequencer_setup(intel_dp);
                 } else {
@@ -4971,8 +5018,8 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
                         intel_dp_init_panel_power_sequencer(dev, intel_dp,
                                                             &power_seq);
                 }
+                pps_unlock(intel_dp);
         }
-        mutex_unlock(&dev_priv->pps_mutex);
 
         intel_dp_aux_init(intel_dp, intel_connector);
 
@@ -4988,9 +5035,9 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
                 drm_dp_aux_unregister(&intel_dp->aux);
                 if (is_edp(intel_dp)) {
                         cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
-                        mutex_lock(&dev_priv->pps_mutex);
+                        pps_lock(intel_dp);
                         edp_panel_vdd_off_sync(intel_dp);
-                        mutex_unlock(&dev_priv->pps_mutex);
+                        pps_unlock(intel_dp);
                 }
                 drm_connector_unregister(connector);
                 drm_connector_cleanup(connector);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 1278b2529d6e..a505bf3ef33b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -946,6 +946,7 @@ void intel_dp_mst_suspend(struct drm_device *dev);
 void intel_dp_mst_resume(struct drm_device *dev);
 int intel_dp_max_link_bw(struct intel_dp *intel_dp);
 void intel_dp_hot_plug(struct intel_encoder *intel_encoder);
+void vlv_power_sequencer_reset(struct drm_i915_private *dev_priv);
 /* intel_dp_mst.c */
 int intel_dp_mst_encoder_init(struct intel_digital_port *intel_dig_port, int conn_id);
 void intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port);
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 49af81f6b4ad..45f71e6dc544 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -6468,6 +6468,8 @@ static void vlv_display_power_well_disable(struct drm_i915_private *dev_priv,
         spin_unlock_irq(&dev_priv->irq_lock);
 
         vlv_set_power_well(dev_priv, power_well, false);
+
+        vlv_power_sequencer_reset(dev_priv);
 }
 
 static void vlv_dpio_cmn_power_well_enable(struct drm_i915_private *dev_priv,