diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index e76dc41f683c..c0f0f11752a2 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -973,6 +973,9 @@ struct intel_fbc { bool enabled; bool active; + bool underrun_detected; + struct work_struct underrun_work; + struct intel_fbc_state_cache { struct { unsigned int mode_flags; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 5e9c15e5e58d..6df0f2f2308a 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1516,6 +1516,7 @@ void intel_fbc_invalidate(struct drm_i915_private *dev_priv, void intel_fbc_flush(struct drm_i915_private *dev_priv, unsigned int frontbuffer_bits, enum fb_op_origin origin); void intel_fbc_cleanup_cfb(struct drm_i915_private *dev_priv); +void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv); /* intel_hdmi.c */ void intel_hdmi_init(struct drm_device *dev, i915_reg_t hdmi_reg, enum port port); diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index faa67624e1ed..617189ae04b4 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -774,6 +774,14 @@ static bool intel_fbc_can_activate(struct intel_crtc *crtc) struct intel_fbc *fbc = &dev_priv->fbc; struct intel_fbc_state_cache *cache = &fbc->state_cache; + /* We don't need to use a state cache here since this information is + * global for all CRTC. + */ + if (fbc->underrun_detected) { + fbc->no_fbc_reason = "underrun detected"; + return false; + } + if (!cache->plane.visible) { fbc->no_fbc_reason = "primary plane not visible"; return false; @@ -859,6 +867,11 @@ static bool intel_fbc_can_choose(struct intel_crtc *crtc) return false; } + if (fbc->underrun_detected) { + fbc->no_fbc_reason = "underrun detected"; + return false; + } + if (fbc_on_pipe_a_only(dev_priv) && crtc->pipe != PIPE_A) { fbc->no_fbc_reason = "no enabled pipes can have FBC"; return false; @@ -1221,6 +1234,59 @@ void intel_fbc_global_disable(struct drm_i915_private *dev_priv) cancel_work_sync(&fbc->work.work); } +static void intel_fbc_underrun_work_fn(struct work_struct *work) +{ + struct drm_i915_private *dev_priv = + container_of(work, struct drm_i915_private, fbc.underrun_work); + struct intel_fbc *fbc = &dev_priv->fbc; + + mutex_lock(&fbc->lock); + + /* Maybe we were scheduled twice. */ + if (fbc->underrun_detected) + goto out; + + DRM_DEBUG_KMS("Disabling FBC due to FIFO underrun.\n"); + fbc->underrun_detected = true; + + intel_fbc_deactivate(dev_priv); +out: + mutex_unlock(&fbc->lock); +} + +/** + * intel_fbc_handle_fifo_underrun_irq - disable FBC when we get a FIFO underrun + * @dev_priv: i915 device instance + * + * Without FBC, most underruns are harmless and don't really cause too many + * problems, except for an annoying message on dmesg. With FBC, underruns can + * become black screens or even worse, especially when paired with bad + * watermarks. So in order for us to be on the safe side, completely disable FBC + * in case we ever detect a FIFO underrun on any pipe. An underrun on any pipe + * already suggests that watermarks may be bad, so try to be as safe as + * possible. + * + * This function is called from the IRQ handler. + */ +void intel_fbc_handle_fifo_underrun_irq(struct drm_i915_private *dev_priv) +{ + struct intel_fbc *fbc = &dev_priv->fbc; + + if (!fbc_supported(dev_priv)) + return; + + /* There's no guarantee that underrun_detected won't be set to true + * right after this check and before the work is scheduled, but that's + * not a problem since we'll check it again under the work function + * while FBC is locked. This check here is just to prevent us from + * unnecessarily scheduling the work, and it relies on the fact that we + * never switch underrun_detect back to false after it's true. */ + if (READ_ONCE(fbc->underrun_detected)) + return; + + schedule_work(&fbc->underrun_work); +} + /** * intel_fbc_init_pipe_state - initialize FBC's CRTC visibility tracking * @dev_priv: i915 device instance @@ -1292,6 +1358,7 @@ void intel_fbc_init(struct drm_i915_private *dev_priv) enum pipe pipe; INIT_WORK(&fbc->work.work, intel_fbc_work_fn); + INIT_WORK(&fbc->underrun_work, intel_fbc_underrun_work_fn); mutex_init(&fbc->lock); fbc->enabled = false; fbc->active = false; diff --git a/drivers/gpu/drm/i915/intel_fifo_underrun.c b/drivers/gpu/drm/i915/intel_fifo_underrun.c index 2aa744081f09..ebb4fed8322e 100644 --- a/drivers/gpu/drm/i915/intel_fifo_underrun.c +++ b/drivers/gpu/drm/i915/intel_fifo_underrun.c @@ -372,6 +372,8 @@ void intel_cpu_fifo_underrun_irq_handler(struct drm_i915_private *dev_priv, if (intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false)) DRM_ERROR("CPU pipe %c FIFO underrun\n", pipe_name(pipe)); + + intel_fbc_handle_fifo_underrun_irq(dev_priv); } /**