From 42e5e65765265485ecf2a480c244d76c2c624449 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Mon, 13 Nov 2017 17:01:40 +0100 Subject: [PATCH] drm/i915: sync dp link status checks against atomic commmits MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Two bits: - check actual atomic state, the legacy stuff can only be looked at from within the atomic_commit_tail function, since it's only protected by ordering and not by any locks. - Make sure we don't wreak the work an ongoing nonblocking commit is doing. v2: We need the crtc lock too, because a plane update might change it without having to acquire the connection_mutex (Maarten). Use Maarten's changes for this locking, while keeping the logic that uses the connection->commit->hw_done signal for syncing with nonblocking commits. v3: The initial state objects from the hw state readout do not have a commit object. Check for that (spotted by CI). v4: Fix deadlock from jumping to put_power with locks still held. (mlankhorst) Cc: Manasi Navare Cc: Maarten Lankhorst Cc: Ville Syrjälä References: https://bugs.freedesktop.org/show_bug.cgi?id=103336 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99272 Signed-off-by: Daniel Vetter Signed-off-by: Maarten Lankhorst Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20171113160140.22679-1-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/i915/intel_dp.c | 61 +++++++++++++++++++++++++++++++++++++---- 1 file changed, 55 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index bc61f38..dd0b3a0 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4277,6 +4277,8 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) { struct drm_i915_private *dev_priv = to_i915(intel_dp_to_dev(intel_dp)); struct intel_encoder *intel_encoder = &dp_to_dig_port(intel_dp)->base; + struct drm_connector_state *conn_state = + intel_dp->attached_connector->base.state; u8 link_status[DP_LINK_STATUS_SIZE]; WARN_ON(!drm_modeset_is_locked(&dev_priv->drm.mode_config.connection_mutex)); @@ -4286,10 +4288,16 @@ intel_dp_check_link_status(struct intel_dp *intel_dp) return; } - if (!intel_encoder->base.crtc) + if (!conn_state->crtc) return; - if (!to_intel_crtc(intel_encoder->base.crtc)->active) + WARN_ON(!drm_modeset_is_locked(&conn_state->crtc->mutex)); + + if (!conn_state->crtc->state->active) + return; + + if (conn_state->commit && + !try_wait_for_completion(&conn_state->commit->hw_done)) return; /* @@ -4364,9 +4372,8 @@ intel_dp_short_pulse(struct intel_dp *intel_dp) DRM_DEBUG_DRIVER("CP or sink specific irq unhandled\n"); } - drm_modeset_lock(&dev_priv->drm.mode_config.connection_mutex, NULL); intel_dp_check_link_status(intel_dp); - drm_modeset_unlock(&dev_priv->drm.mode_config.connection_mutex); + if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) { DRM_DEBUG_KMS("Link Training Compliance Test requested\n"); /* Send a Hotplug Uevent to userspace to start modeset */ @@ -4814,8 +4821,19 @@ intel_dp_detect(struct drm_connector *connector, connector->base.id, connector->name); /* If full detect is not performed yet, do a full detect */ - if (!intel_dp->detect_done) + if (!intel_dp->detect_done) { + struct drm_crtc *crtc; + int ret; + + crtc = connector->state->crtc; + if (crtc) { + ret = drm_modeset_lock(&crtc->mutex, ctx); + if (ret) + return ret; + } + status = intel_dp_long_pulse(intel_dp->attached_connector); + } intel_dp->detect_done = false; @@ -5097,7 +5115,38 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) } if (!intel_dp->is_mst) { - if (!intel_dp_short_pulse(intel_dp)) { + struct drm_modeset_acquire_ctx ctx; + struct drm_connector *connector = &intel_dp->attached_connector->base; + struct drm_crtc *crtc; + int iret; + bool handled = false; + + drm_modeset_acquire_init(&ctx, 0); +retry: + iret = drm_modeset_lock(&dev_priv->drm.mode_config.connection_mutex, &ctx); + if (iret) + goto err; + + crtc = connector->state->crtc; + if (crtc) { + iret = drm_modeset_lock(&crtc->mutex, &ctx); + if (iret) + goto err; + } + + handled = intel_dp_short_pulse(intel_dp); + +err: + if (iret == -EDEADLK) { + drm_modeset_backoff(&ctx); + goto retry; + } + + drm_modeset_drop_locks(&ctx); + drm_modeset_acquire_fini(&ctx); + WARN(iret, "Acquiring modeset locks failed with %i\n", iret); + + if (!handled) { intel_dp->detect_done = false; goto put_power; } -- 2.7.4