[CI v3 21/23] drm/i915: Add state verification for the TypeC port mode

Imre Deak
2019-06-26T20:50:20Z

Add state verification for the TypeC port mode wrt. the port's AUX power
well enabling/disabling. Also check the correctness of changing the port
mode:
- When enabling/disabling the AUX power well for a TypeC port we must hold
the TypeC port lock - the case for AUX transfers - or hold a Type C
port link reference - the case for modeset enabling/disabling.
- When changing the TypeC port mode the port's AUX power domain must be
disabled.

v2: (Ville)
- Simplify power_well_async_ref_count().
- Fix the commit log, clarifying what are the valid conditions to
enable/disable the AUX power wells.

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
.../drm/i915/display/intel_display_power.c | 95 +++++++++++++++++--
drivers/gpu/drm/i915/display/intel_tc.c | 2 +
drivers/gpu/drm/i915/display/intel_tc.h | 10 +-
3 files changed, 98 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index fd13cd68deae..86a38116dc3a 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -17,6 +17,7 @@
#include "intel_drv.h"
#include "intel_hotplug.h"
#include "intel_sideband.h"
+#include "intel_tc.h"

bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv,
enum i915_power_well_id power_well_id);
@@ -447,26 +448,106 @@ icl_combo_phy_aux_power_well_disable(struct drm_i915_private *dev_priv,
#define ICL_TBT_AUX_PW_TO_CH(pw_idx) \
((pw_idx) - ICL_PW_CTL_IDX_AUX_TBT1 + AUX_CH_C)

+static enum aux_ch icl_tc_phy_aux_ch(struct drm_i915_private *dev_priv,
+ struct i915_power_well *power_well)
+{
+ int pw_idx = power_well->desc->hsw.idx;
+
+ return power_well->desc->hsw.is_tc_tbt ? ICL_TBT_AUX_PW_TO_CH(pw_idx) :
+ ICL_AUX_PW_TO_CH(pw_idx);
+}
+
+#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
+
+static u64 async_put_domains_mask(struct i915_power_domains *power_domains);
+
+static int power_well_async_ref_count(struct drm_i915_private *dev_priv,
+ struct i915_power_well *power_well)
+{
+ int refs = hweight64(power_well->desc->domains &
+ async_put_domains_mask(&dev_priv->power_domains));
+
+ WARN_ON(refs > power_well->count);
+
+ return refs;
+}
+
+static void icl_tc_port_assert_ref_held(struct drm_i915_private *dev_priv,
+ struct i915_power_well *power_well)
+{
+ enum aux_ch aux_ch = icl_tc_phy_aux_ch(dev_priv, power_well);
+ struct intel_digital_port *dig_port = NULL;
+ struct intel_encoder *encoder;
+
+ /* Bypass the check if all references are released asynchronously */
+ if (power_well_async_ref_count(dev_priv, power_well) ==
+ power_well->count)
+ return;
+
+ aux_ch = icl_tc_phy_aux_ch(dev_priv, power_well);
+
+ for_each_intel_encoder(&dev_priv->drm, encoder) {
+ if (!intel_port_is_tc(dev_priv, encoder->port))
+ continue;
+
+ /* We'll check the MST primary port */
+ if (encoder->type == INTEL_OUTPUT_DP_MST)
+ continue;
+
+ dig_port = enc_to_dig_port(&encoder->base);
+ if (WARN_ON(!dig_port))
+ continue;
+
+ if (dig_port->aux_ch != aux_ch) {
+ dig_port = NULL;
+ continue;
+ }
+
+ break;
+ }
+
+ if (WARN_ON(!dig_port))
+ return;
+
+ WARN_ON(!intel_tc_port_ref_held(dig_port));
+}
+
+#else
+
+static void icl_tc_port_assert_ref_held(struct drm_i915_private *dev_priv,
+ struct i915_power_well *power_well)
+{
+}
+
+#endif
+
static void
icl_tc_phy_aux_power_well_enable(struct drm_i915_private *dev_priv,
struct i915_power_well *power_well)
{
- int pw_idx = power_well->desc->hsw.idx;
- bool is_tbt = power_well->desc->hsw.is_tc_tbt;
- enum aux_ch aux_ch;
+ enum aux_ch aux_ch = icl_tc_phy_aux_ch(dev_priv, power_well);
u32 val;

- aux_ch = is_tbt ? ICL_TBT_AUX_PW_TO_CH(pw_idx) :
- ICL_AUX_PW_TO_CH(pw_idx);
+ icl_tc_port_assert_ref_held(dev_priv, power_well);
+
val = I915_READ(DP_AUX_CH_CTL(aux_ch));
val &= ~DP_AUX_CH_CTL_TBT_IO;
- if (is_tbt)
+ if (power_well->desc->hsw.is_tc_tbt)
val |= DP_AUX_CH_CTL_TBT_IO;
I915_WRITE(DP_AUX_CH_CTL(aux_ch), val);

hsw_power_well_enable(dev_priv, power_well);
}

+static void
+icl_tc_phy_aux_power_well_disable(struct drm_i915_private *dev_priv,
+ struct i915_power_well *power_well)
+{
+ icl_tc_port_assert_ref_held(dev_priv, power_well);
+
+ hsw_power_well_disable(dev_priv, power_well);
+}
+
/*
* We should only use the power well if we explicitly asked the hardware to
* enable it, so check if it's enabled and also check if we've requested it to
@@ -3119,7 +3200,7 @@ static const struct i915_power_well_ops icl_combo_phy_aux_power_well_ops = {
static const struct i915_power_well_ops icl_tc_phy_aux_power_well_ops = {
.sync_hw = hsw_power_well_sync_hw,
.enable = icl_tc_phy_aux_power_well_enable,
- .disable = hsw_power_well_disable,
+ .disable = icl_tc_phy_aux_power_well_disable,
.is_enabled = hsw_power_well_enabled,
};

diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c
index ba6492bc0ee0..467dd3ec541b 100644
--- a/drivers/gpu/drm/i915/display/intel_tc.c
+++ b/drivers/gpu/drm/i915/display/intel_tc.c
@@ -319,6 +319,8 @@ static void intel_tc_port_reset_mode(struct intel_digital_port *dig_port,
enum tc_port_mode old_tc_mode = dig_port->tc_mode;

intel_display_power_flush_work(dev_priv);
+ WARN_ON(intel_display_power_is_enabled(dev_priv,
+ intel_aux_power_domain(dig_port)));

icl_tc_phy_disconnect(dig_port);
icl_tc_phy_connect(dig_port, required_lanes);
diff --git a/drivers/gpu/drm/i915/display/intel_tc.h b/drivers/gpu/drm/i915/display/intel_tc.h
index 31af7be96070..8adc107cdbcb 100644
--- a/drivers/gpu/drm/i915/display/intel_tc.h
+++ b/drivers/gpu/drm/i915/display/intel_tc.h
@@ -7,8 +7,8 @@
#define __INTEL_TC_H__

#include <linux/types.h>
-
-struct intel_digital_port;
+#include <linux/mutex.h>
+#include "intel_drv.h"

void icl_tc_phy_disconnect(struct intel_digital_port *dig_port);

@@ -23,6 +23,12 @@ void intel_tc_port_get_link(struct intel_digital_port *dig_port,
int required_lanes);
void intel_tc_port_put_link(struct intel_digital_port *dig_port);

+static inline int intel_tc_port_ref_held(struct intel_digital_port *dig_port)
+{
+ return mutex_is_locked(&dig_port->tc_lock) ||
+ dig_port->tc_link_refcount;
+}
+
void intel_tc_port_init(struct intel_digital_port *dig_port, bool is_legacy);

#endif /* __INTEL_TC_H__ */