[PATCH v2 10.1/14] drm/i915: Reset power sequencer pipe tracking when disp2d is off

ville.syrjala
2014-08-22T14:22:14Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

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

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
Imre noticed my previouys attempt was utter garbage. Let's try again. Again maybe
we want to squash with 10/14 or at least move the edp_pps_{lock,unlock}() introduction
there to avoid churn.

The alternative of trying to plumb all the power domain calls out from under
pps_mutex seemed a bit too nasty to me, so I opted for this approach instead.

drivers/gpu/drm/i915/intel_dp.c | 157 +++++++++++++++++++++++++--------------
drivers/gpu/drm/i915/intel_drv.h | 1 +
drivers/gpu/drm/i915/intel_pm.c | 2 +
3 files changed, 106 insertions(+), 54 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index d6fe1a2..3468315 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -389,6 +389,67 @@ 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.
+ * edp_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 void edp_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 edp_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 u32 _pp_ctrl_reg(struct intel_dp *intel_dp)
{
struct drm_device *dev = intel_dp_to_dev(intel_dp);
@@ -425,7 +486,7 @@ static int edp_notify_handler(struct notifier_block *this, unsigned long code,
if (!IS_VALLEYVIEW(dev) || !is_edp(intel_dp) || code != SYS_RESTART)
return 0;

- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);

pipe = vlv_power_sequencer_pipe(intel_dp);

@@ -439,7 +500,7 @@ static int edp_notify_handler(struct notifier_block *this, unsigned long code,
I915_WRITE(pp_ctrl_reg, PANEL_UNLOCK_REGS | PANEL_POWER_OFF);
msleep(intel_dp->panel_power_cycle_delay);

- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);

return 0;
}
@@ -458,17 +519,13 @@ 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
intel_dp_check_edp(struct intel_dp *intel_dp)
{
@@ -614,7 +671,7 @@ 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);
+ edp_pps_lock(intel_dp);

/*
* We will be called with VDD already enabled for dpcd/edid/oui reads.
@@ -731,7 +788,7 @@ out:
if (vdd)
edp_panel_vdd_off(intel_dp, false);

- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);

return ret;
}
@@ -1312,16 +1369,14 @@ 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);
+ edp_pps_lock(intel_dp);
vdd = edp_panel_vdd_on(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);

WARN(!vdd, "eDP VDD already requested on\n");
}
@@ -1370,13 +1425,11 @@ 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);
+ edp_pps_lock(intel_dp);
if (!intel_dp->want_panel_vdd)
edp_panel_vdd_off_sync(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

static void edp_panel_vdd_schedule_off(struct intel_dp *intel_dp)
@@ -1414,15 +1467,12 @@ 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);
+ edp_pps_lock(intel_dp);
edp_panel_vdd_off(intel_dp, sync);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

void intel_edp_panel_on(struct intel_dp *intel_dp)
@@ -1437,7 +1487,7 @@ void intel_edp_panel_on(struct intel_dp *intel_dp)

DRM_DEBUG_KMS("Turn eDP power on\n");

- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);

if (edp_have_panel_power(intel_dp)) {
DRM_DEBUG_KMS("eDP power already on\n");
@@ -1472,7 +1522,7 @@ void intel_edp_panel_on(struct intel_dp *intel_dp)
}

out:
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

void intel_edp_panel_off(struct intel_dp *intel_dp)
@@ -1490,7 +1540,7 @@ void intel_edp_panel_off(struct intel_dp *intel_dp)

DRM_DEBUG_KMS("Turn eDP power off\n");

- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);

WARN(!intel_dp->want_panel_vdd, "Need VDD to turn off panel\n");

@@ -1514,7 +1564,7 @@ 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);
+ edp_pps_unlock(intel_dp);
}

void intel_edp_backlight_on(struct intel_dp *intel_dp)
@@ -1540,7 +1590,7 @@ void intel_edp_backlight_on(struct intel_dp *intel_dp)
*/
wait_backlight_on(intel_dp);

- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);

pp = ironlake_get_pp_control(intel_dp);
pp |= EDP_BLC_ENABLE;
@@ -1550,7 +1600,7 @@ 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);
+ edp_pps_unlock(intel_dp);
}

void intel_edp_backlight_off(struct intel_dp *intel_dp)
@@ -1563,7 +1613,7 @@ void intel_edp_backlight_off(struct intel_dp *intel_dp)
if (!is_edp(intel_dp))
return;

- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);

DRM_DEBUG_KMS("\n");
pp = ironlake_get_pp_control(intel_dp);
@@ -1574,7 +1624,7 @@ 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);
+ edp_pps_unlock(intel_dp);

intel_dp->last_backlight_off = jiffies;
edp_wait_backlight_off(intel_dp);
@@ -2290,18 +2340,19 @@ 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);
@@ -2377,9 +2428,9 @@ 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);
+ edp_pps_lock(intel_dp);
vlv_init_panel_power_sequencer(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

intel_enable_dp(encoder);
@@ -2477,9 +2528,9 @@ 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);
+ edp_pps_lock(intel_dp);
vlv_init_panel_power_sequencer(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

intel_enable_dp(encoder);
@@ -4219,17 +4270,16 @@ 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);
+ edp_pps_lock(intel_dp);
edp_panel_vdd_off_sync(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_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;
@@ -4241,15 +4291,13 @@ 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);
+ edp_pps_lock(intel_dp);
edp_panel_vdd_off_sync(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

static void intel_dp_encoder_reset(struct drm_encoder *encoder)
@@ -4727,9 +4775,10 @@ 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);
+
+ edp_pps_lock(intel_dp);
+
if (!edp_have_panel_vdd(intel_dp))
goto out;
/*
@@ -4744,7 +4793,7 @@ 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);
+ edp_pps_unlock(intel_dp);
}

static bool intel_edp_init_connector(struct intel_dp *intel_dp,
@@ -4786,9 +4835,9 @@ 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);
+ edp_pps_lock(intel_dp);
intel_dp_init_panel_power_sequencer_registers(dev, intel_dp, power_seq);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);

mutex_lock(&dev->mode_config.mutex);
edid = drm_get_edid(connector, &intel_dp->aux.ddc);
@@ -4922,14 +4971,14 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
}

if (is_edp(intel_dp)) {
- mutex_lock(&dev_priv->pps_mutex);
+ edp_pps_lock(intel_dp);
if (IS_VALLEYVIEW(dev)) {
vlv_initial_power_sequencer_setup(intel_dp);
} else {
intel_dp_init_panel_power_timestamps(intel_dp);
intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
}
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_pps_unlock(intel_dp);
}

intel_dp_aux_init(intel_dp, intel_connector);
@@ -4945,9 +4994,9 @@ 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);
+ edp_pps_lock(intel_dp);
edp_panel_vdd_off_sync(intel_dp);
- mutex_unlock(&dev_priv->pps_mutex);
+ edp_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 849a447..32627ae 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -943,6 +943,7 @@ 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 39dd066..d5ffda9 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -6328,6 +6328,8 @@ 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,
--
1.8.5.5