drm/i915: Check for FIFO underruns at the end of modeset on gmch
FIFO underruns don't generate interrupts on gmch platforms, so
if we want to know whether a modeset triggered FIFO underruns we
need to explicitly check for them.
As a modeset on one pipe could cause underruns on other pipes,
check for underruns on all pipes.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Thomas Wood <thomas.wood@intel.com>
[danvet: Fix up merge error, kudos to Ville for noticing it.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 83ad4b4..57e86ba 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -306,6 +306,34 @@
return true;
}
+void i9xx_check_fifo_underruns(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *crtc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev_priv->irq_lock, flags);
+
+ for_each_intel_crtc(dev, crtc) {
+ u32 reg = PIPESTAT(crtc->pipe);
+ u32 pipestat;
+
+ if (crtc->cpu_fifo_underrun_disabled)
+ continue;
+
+ pipestat = I915_READ(reg) & 0xffff0000;
+ if ((pipestat & PIPE_FIFO_UNDERRUN_STATUS) == 0)
+ continue;
+
+ I915_WRITE(reg, pipestat | PIPE_FIFO_UNDERRUN_STATUS);
+ POSTING_READ(reg);
+
+ DRM_ERROR("pipe %c underrun\n", pipe_name(crtc->pipe));
+ }
+
+ spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
+}
+
static void i9xx_set_fifo_underrun_reporting(struct drm_device *dev,
enum pipe pipe, bool enable)
{
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 6c5db7c..8d960d2 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4625,6 +4625,9 @@
intel_crtc_enable_planes(crtc);
drm_crtc_vblank_on(crtc);
+
+ /* Underruns don't raise interrupts, so check manually. */
+ i9xx_check_fifo_underruns(dev);
}
static void i9xx_set_pll_dividers(struct intel_crtc *crtc)
@@ -4704,6 +4707,9 @@
intel_crtc_enable_planes(crtc);
drm_crtc_vblank_on(crtc);
+
+ /* Underruns don't raise interrupts, so check manually. */
+ i9xx_check_fifo_underruns(dev);
}
static void i9xx_pfit_disable(struct intel_crtc *crtc)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index a78eb75..fe2533b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -680,6 +680,7 @@
void intel_runtime_pm_disable_interrupts(struct drm_device *dev);
void intel_runtime_pm_restore_interrupts(struct drm_device *dev);
int intel_get_crtc_scanline(struct intel_crtc *crtc);
+void i9xx_check_fifo_underruns(struct drm_device *dev);
/* intel_crt.c */