Currently we perform both short IRQ handling for DP, and connector reprobing in the HPD IRQ handler. However since we need to grab connection_mutex in order to reprobe a connector, in theory we could accidentally block ourselves from handling any short IRQs until after a modeset completes if a connector hotplug happens to occur in parallel with a modeset.
I haven't seen this actually happen yet, but since we're cleaning up nouveau's hotplug handling code anyway and we already have a hpd worker, we can simply fix this by only relying on the HPD worker to actually reprobe connectors when we receive a HPD IRQ. We also add a mask to nouveau_drm to keep track of which connectors are waiting to be reprobed in response to an HPD IRQ.
Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/nouveau/nouveau_connector.c | 42 +++++-------- drivers/gpu/drm/nouveau/nouveau_connector.h | 1 + drivers/gpu/drm/nouveau/nouveau_display.c | 70 ++++++++++++++++++--- drivers/gpu/drm/nouveau/nouveau_display.h | 1 + drivers/gpu/drm/nouveau/nouveau_dp.c | 2 +- drivers/gpu/drm/nouveau/nouveau_drm.c | 4 +- drivers/gpu/drm/nouveau/nouveau_drv.h | 2 + 7 files changed, 86 insertions(+), 36 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c index 4a29f691c08e4..637e91594fbe8 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.c +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c @@ -1138,6 +1138,20 @@ nouveau_connector_funcs_lvds = { .early_unregister = nouveau_connector_early_unregister, };
+void +nouveau_connector_hpd(struct drm_connector *connector) +{ + struct nouveau_drm *drm = nouveau_drm(connector->dev); + u32 mask = drm_connector_mask(connector); + + mutex_lock(&drm->hpd_lock); + if (!(drm->hpd_pending & mask)) { + drm->hpd_pending |= mask; + schedule_work(&drm->hpd_work); + } + mutex_unlock(&drm->hpd_lock); +} + static int nouveau_connector_hotplug(struct nvif_notify *notify) { @@ -1147,8 +1161,6 @@ nouveau_connector_hotplug(struct nvif_notify *notify) struct drm_device *dev = connector->dev; struct nouveau_drm *drm = nouveau_drm(dev); const struct nvif_notify_conn_rep_v0 *rep = notify->data; - const char *name = connector->name; - int ret; bool plugged = (rep->mask != NVIF_NOTIFY_CONN_V0_UNPLUG);
if (rep->mask & NVIF_NOTIFY_CONN_V0_IRQ) { @@ -1156,31 +1168,9 @@ nouveau_connector_hotplug(struct nvif_notify *notify) return NVIF_NOTIFY_KEEP; }
- ret = pm_runtime_get(drm->dev->dev); - if (ret == 0) { - /* We can't block here if there's a pending PM request - * running, as we'll deadlock nouveau_display_fini() when it - * calls nvif_put() on our nvif_notify struct. So, simply - * defer the hotplug event until the device finishes resuming - */ - NV_DEBUG(drm, "Deferring HPD on %s until runtime resume\n", - name); - schedule_work(&drm->hpd_work); - - pm_runtime_put_noidle(drm->dev->dev); - return NVIF_NOTIFY_KEEP; - } else if (ret != 1 && ret != -EACCES) { - NV_WARN(drm, "HPD on %s dropped due to RPM failure: %d\n", - name, ret); - return NVIF_NOTIFY_DROP; - } - - NV_DEBUG(drm, "%splugged %s\n", plugged ? "" : "un", name); - - drm_helper_hpd_irq_event(connector->dev); + NV_DEBUG(drm, "%splugged %s\n", plugged ? "" : "un", connector->name); + nouveau_connector_hpd(connector);
- pm_runtime_mark_last_busy(drm->dev->dev); - pm_runtime_put_autosuspend(drm->dev->dev); return NVIF_NOTIFY_KEEP; }
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.h b/drivers/gpu/drm/nouveau/nouveau_connector.h index d6de5cb8e2238..d0b859c4a80ea 100644 --- a/drivers/gpu/drm/nouveau/nouveau_connector.h +++ b/drivers/gpu/drm/nouveau/nouveau_connector.h @@ -187,6 +187,7 @@ nouveau_crtc_connector_get(struct nouveau_crtc *nv_crtc)
struct drm_connector * nouveau_connector_create(struct drm_device *, const struct dcb_output *); +void nouveau_connector_hpd(struct drm_connector *connector);
extern int nouveau_tv_disable; extern int nouveau_ignorelid; diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c index 13016769a194b..bceb48a2dfca6 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.c +++ b/drivers/gpu/drm/nouveau/nouveau_display.c @@ -457,16 +457,70 @@ static struct nouveau_drm_prop_enum_list dither_depth[] = { } \ } while(0)
+void +nouveau_display_hpd_resume(struct drm_device *dev) +{ + struct nouveau_drm *drm = nouveau_drm(dev); + + mutex_lock(&drm->hpd_lock); + drm->hpd_pending = ~0; + mutex_unlock(&drm->hpd_lock); + + schedule_work(&drm->hpd_work); +} + static void nouveau_display_hpd_work(struct work_struct *work) { struct nouveau_drm *drm = container_of(work, typeof(*drm), hpd_work); + struct drm_device *dev = drm->dev; + struct drm_connector *connector; + struct drm_connector_list_iter conn_iter; + u32 pending; + bool changed = false; + + pm_runtime_get_sync(dev->dev);
- pm_runtime_get_sync(drm->dev->dev); + mutex_lock(&drm->hpd_lock); + pending = drm->hpd_pending; + drm->hpd_pending = 0; + mutex_unlock(&drm->hpd_lock);
- drm_helper_hpd_irq_event(drm->dev); + /* Nothing to do, exit early without updating the last busy counter */ + if (!pending) + goto noop; + + mutex_lock(&dev->mode_config.mutex); + drm_connector_list_iter_begin(dev, &conn_iter); + + nouveau_for_each_non_mst_connector_iter(connector, &conn_iter) { + enum drm_connector_status old_status = connector->status; + u64 old_epoch_counter = connector->epoch_counter; + + if (!(pending & drm_connector_mask(connector))) + continue; + + connector->status = drm_helper_probe_detect(connector, NULL, + false); + if (old_epoch_counter == connector->epoch_counter) + continue; + + changed = true; + drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s (epoch counter %llu->%llu)\n", + connector->base.id, connector->name, + drm_get_connector_status_name(old_status), + drm_get_connector_status_name(connector->status), + old_epoch_counter, connector->epoch_counter); + } + + drm_connector_list_iter_end(&conn_iter); + mutex_unlock(&dev->mode_config.mutex); + + if (changed) + drm_kms_helper_hotplug_event(dev);
pm_runtime_mark_last_busy(drm->dev->dev); +noop: pm_runtime_put_sync(drm->dev->dev); }
@@ -490,12 +544,11 @@ nouveau_display_acpi_ntfy(struct notifier_block *nb, unsigned long val, */ pm_runtime_put_autosuspend(drm->dev->dev); } else if (ret == 0) { - /* This may be the only indication we receive - * of a connector hotplug on a runtime - * suspended GPU, schedule hpd_work to check. + /* We've started resuming the GPU already, so + * it will handle scheduling a full reprobe + * itself */ NV_DEBUG(drm, "ACPI requested connector reprobe\n"); - schedule_work(&drm->hpd_work); pm_runtime_put_noidle(drm->dev->dev); } else { NV_WARN(drm, "Dropped ACPI reprobe event due to RPM error: %d\n", @@ -686,6 +739,7 @@ nouveau_display_create(struct drm_device *dev) }
INIT_WORK(&drm->hpd_work, nouveau_display_hpd_work); + mutex_init(&drm->hpd_lock); #ifdef CONFIG_ACPI drm->acpi_nb.notifier_call = nouveau_display_acpi_ntfy; register_acpi_notifier(&drm->acpi_nb); @@ -705,9 +759,10 @@ void nouveau_display_destroy(struct drm_device *dev) { struct nouveau_display *disp = nouveau_display(dev); + struct nouveau_drm *drm = nouveau_drm(dev);
#ifdef CONFIG_ACPI - unregister_acpi_notifier(&nouveau_drm(dev)->acpi_nb); + unregister_acpi_notifier(&drm->acpi_nb); #endif
drm_kms_helper_poll_fini(dev); @@ -719,6 +774,7 @@ nouveau_display_destroy(struct drm_device *dev) nvif_disp_dtor(&disp->disp);
nouveau_drm(dev)->display = NULL; + mutex_destroy(&drm->hpd_lock); kfree(disp); }
diff --git a/drivers/gpu/drm/nouveau/nouveau_display.h b/drivers/gpu/drm/nouveau/nouveau_display.h index 76ba93e01aff4..616c434270594 100644 --- a/drivers/gpu/drm/nouveau/nouveau_display.h +++ b/drivers/gpu/drm/nouveau/nouveau_display.h @@ -45,6 +45,7 @@ nouveau_display(struct drm_device *dev) int nouveau_display_create(struct drm_device *dev); void nouveau_display_destroy(struct drm_device *dev); int nouveau_display_init(struct drm_device *dev, bool resume, bool runtime); +void nouveau_display_hpd_resume(struct drm_device *dev); void nouveau_display_fini(struct drm_device *dev, bool suspend, bool runtime); int nouveau_display_suspend(struct drm_device *dev, bool runtime); void nouveau_display_resume(struct drm_device *dev, bool runtime); diff --git a/drivers/gpu/drm/nouveau/nouveau_dp.c b/drivers/gpu/drm/nouveau/nouveau_dp.c index 201c0b4335563..71d095409c90d 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dp.c +++ b/drivers/gpu/drm/nouveau/nouveau_dp.c @@ -165,7 +165,7 @@ void nouveau_dp_irq(struct nouveau_drm *drm,
if (mstm && mstm->is_mst) { if (!nv50_mstm_service(drm, nv_connector, mstm)) - schedule_work(&drm->hpd_work); + nouveau_connector_hpd(connector); } else { drm_dp_cec_irq(&nv_connector->aux); } diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c index 22d246acc5e52..42fc5c813a9bb 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drm.c +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c @@ -953,7 +953,7 @@ nouveau_pmops_resume(struct device *dev) ret = nouveau_do_resume(drm_dev, false);
/* Monitors may have been connected / disconnected during suspend */ - schedule_work(&nouveau_drm(drm_dev)->hpd_work); + nouveau_display_hpd_resume(drm_dev);
return ret; } @@ -1036,7 +1036,7 @@ nouveau_pmops_runtime_resume(struct device *dev) drm_dev->switch_power_state = DRM_SWITCH_POWER_ON;
/* Monitors may have been connected / disconnected during suspend */ - schedule_work(&nouveau_drm(drm_dev)->hpd_work); + nouveau_display_hpd_resume(drm_dev);
return ret; } diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h index f63ac72aa556f..73ebf5fba2fcd 100644 --- a/drivers/gpu/drm/nouveau/nouveau_drv.h +++ b/drivers/gpu/drm/nouveau/nouveau_drv.h @@ -198,6 +198,8 @@ struct nouveau_drm { struct nvbios vbios; struct nouveau_display *display; struct work_struct hpd_work; + struct mutex hpd_lock; + u32 hpd_pending; struct work_struct fbcon_work; int fbcon_new_state; #ifdef CONFIG_ACPI