Some unpowered USB type-c dongles requires some time to power on before being able to process aux channel transactions.
It was not a problem for older platforms because there was a hardware bridge between DDI/DP ports and type-c controller adding a implicit delay that hid this issue but ICL have type-c controllers integrated to the SOC, causing sinks to not be detected. So here it test if DP type-c port is responsive before proceed with hotplug sequence, it try 5 times with a 150ms of delay between tries before giving up. If unpowered TBT dongles shows up in the market this approach should be extended to TBT ports too. Signed-off-by: José Roberto de Souza <[email protected]> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/intel_ddi.c | 4 + drivers/gpu/drm/i915/intel_drv.h | 2 + drivers/gpu/drm/i915/intel_hotplug.c | 108 +++++++++++++++++++++++++++ 4 files changed, 115 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 03db011caa8e..3fd8c3fa6515 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2639,6 +2639,7 @@ enum hpd_pin intel_hpd_pin_default(struct drm_i915_private *dev_priv, enum port port); bool intel_hpd_disable(struct drm_i915_private *dev_priv, enum hpd_pin pin); void intel_hpd_enable(struct drm_i915_private *dev_priv, enum hpd_pin pin); +void intel_hotplug_tc_wa_work(struct work_struct *work); /* i915_irq.c */ static inline void i915_queue_hangcheck(struct drm_i915_private *dev_priv) diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index b0bb8dfc2ed5..2c149843cacf 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -4258,6 +4258,10 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port) goto err; intel_dig_port->hpd_pulse = intel_dp_hpd_pulse; + + if (IS_ICELAKE(dev_priv) && intel_port_is_tc(dev_priv, port)) + INIT_DELAYED_WORK(&intel_dig_port->tc_wa_work, + intel_hotplug_tc_wa_work); } /* In theory we don't need the encoder->type check, but leave it just in diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 33b733d37706..fbb6f78ce733 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1242,6 +1242,8 @@ struct intel_digital_port { enum intel_display_power_domain ddi_io_power_domain; bool tc_legacy_port:1; enum tc_port_type tc_type; + struct delayed_work tc_wa_work; + u8 tc_wa_count; void (*write_infoframe)(struct intel_encoder *encoder, const struct intel_crtc_state *crtc_state, diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c index e027d2b4abe5..9838b60e8f63 100644 --- a/drivers/gpu/drm/i915/intel_hotplug.c +++ b/drivers/gpu/drm/i915/intel_hotplug.c @@ -342,6 +342,74 @@ static void i915_digport_work_func(struct work_struct *work) } } +#define TC_WA_DELAY_MSEC 150 +#define TC_WA_TRIES 5 + +/* + * Test if type-c dongle is responsive return true if so otherwise schedule a + * work to try again and return false. + */ +static bool intel_hotplug_tc_wa_test(struct intel_digital_port *dig_port) +{ + struct intel_dp *intel_dp = &dig_port->dp; + u8 buffer; + + dig_port->tc_wa_count++; + + if (drm_dp_dpcd_read(&intel_dp->aux, DP_DPCD_REV, &buffer, 1) != 1) + goto not_responsive; + + if (!drm_probe_ddc(&intel_dp->aux.ddc)) + goto not_responsive; + + return true; + +not_responsive: + if (dig_port->tc_wa_count < TC_WA_TRIES) { + const unsigned long delay = msecs_to_jiffies(TC_WA_DELAY_MSEC); + + schedule_delayed_work(&dig_port->tc_wa_work, delay); + } else { + DRM_DEBUG_KMS("TC port not responsive, giving up\n"); + } + + return false; +} + +void intel_hotplug_tc_wa_work(struct work_struct *work) +{ + struct delayed_work *delayed_work = to_delayed_work(work); + struct intel_digital_port *dig_port = container_of(delayed_work, + struct intel_digital_port, + tc_wa_work); + struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev); + struct intel_encoder *intel_encoder = &dig_port->base; + struct intel_dp *intel_dp = &dig_port->dp; + struct intel_connector *intel_connector = intel_dp->attached_connector; + struct drm_device *dev = &dev_priv->drm; + intel_wakeref_t wakeref; + bool ret; + + wakeref = intel_runtime_pm_get(dev_priv); + + if (!intel_digital_port_connected(intel_encoder) || + dig_port->tc_type != TC_PORT_TYPEC) { + intel_runtime_pm_put(dev_priv, wakeref); + return; + } + + mutex_lock(&dev->mode_config.mutex); + ret = intel_hotplug_tc_wa_test(dig_port); + if (ret) + ret = intel_encoder->hotplug(intel_encoder, intel_connector); + mutex_unlock(&dev->mode_config.mutex); + + if (ret) + drm_kms_helper_hotplug_event(dev); + + intel_runtime_pm_put(dev_priv, wakeref); +} + /* * Handle hotplug events outside the interrupt handler proper. */ @@ -377,9 +445,37 @@ static void i915_hotplug_work_func(struct work_struct *work) continue; intel_encoder = intel_connector->encoder; if (hpd_event_bits & (1 << intel_encoder->hpd_pin)) { + struct intel_digital_port *dig_port = enc_to_dig_port(&intel_encoder->base); + DRM_DEBUG_KMS("Connector %s (pin %i) received hotplug event.\n", connector->name, intel_encoder->hpd_pin); + /* + * Type-C dongles WA: Unpowered type-C dongles can take + * some time to be responsible, so let's try to do a + * DPCD read to check if it is ready, otherwise skip + * the call to the hotplug callback and schedule a work + * to try a DPCD read again after a few micro-seconds. + */ + if (IS_ICELAKE(dev_priv) && + intel_port_is_tc(dev_priv, intel_encoder->port)) { + intel_wakeref_t wakeref; + bool skip_hotplug = false; + + wakeref = intel_runtime_pm_get(dev_priv); + + if (intel_digital_port_connected(intel_encoder) && + dig_port->tc_type == TC_PORT_TYPEC) { + dig_port->tc_wa_count = 0; + skip_hotplug = !intel_hotplug_tc_wa_test(dig_port); + } + + intel_runtime_pm_put(dev_priv, wakeref); + + if (skip_hotplug) + continue; + } + changed |= intel_encoder->hotplug(intel_encoder, intel_connector); } @@ -644,6 +740,8 @@ void intel_hpd_init_work(struct drm_i915_private *dev_priv) void intel_hpd_cancel_work(struct drm_i915_private *dev_priv) { + struct intel_encoder *encoder; + spin_lock_irq(&dev_priv->irq_lock); dev_priv->hotplug.long_port_mask = 0; @@ -656,6 +754,16 @@ void intel_hpd_cancel_work(struct drm_i915_private *dev_priv) cancel_work_sync(&dev_priv->hotplug.hotplug_work); cancel_work_sync(&dev_priv->hotplug.poll_init_work); cancel_delayed_work_sync(&dev_priv->hotplug.reenable_work); + + for_each_intel_encoder(&dev_priv->drm, encoder) { + struct intel_digital_port *dig_port; + + dig_port = enc_to_dig_port(&encoder->base); + /* tc_wa_work is only initialized for TC with DP ports */ + if (IS_ICELAKE(dev_priv) && dig_port && dig_port->hpd_pulse) + cancel_delayed_work_sync(&dig_port->tc_wa_work); + } + } bool intel_hpd_disable(struct drm_i915_private *dev_priv, enum hpd_pin pin) -- 2.20.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
