[PATCH 07/21] drm/i915: Wire up cpu fifo underrun reporting support for bdw

Ben Widawsky
2013-11-08T06:09:09Z

From: Daniel Vetter <daniel.vetter@ffwll.ch>

HW engineers have listened and given us again a real interrupt with
masking and status regs. Yay!

For consistency with other platforms call the #define FIFO_UNDERRUN.
Eventually we also might need to have some enable/disable functions
for bdw display interrupts, but for now open-coding seems to be good
enough.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
drivers/gpu/drm/i915/i915_irq.c | 25 +++++++++++++++++++++++++
drivers/gpu/drm/i915/i915_reg.h | 2 +-
2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 9ea0df2..bf71e35 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -270,6 +270,21 @@ static void ivybridge_set_fifo_underrun_reporting(struct drm_device *dev,
}
}

+static void broadwell_set_fifo_underrun_reporting(struct drm_device *dev,
+ enum pipe pipe, bool enable)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+
+ assert_spin_locked(&dev_priv->irq_lock);
+
+ if (enable)
+ dev_priv->de_irq_mask[pipe] &= ~GEN8_PIPE_FIFO_UNDERRUN;
+ else
+ dev_priv->de_irq_mask[pipe] |= GEN8_PIPE_FIFO_UNDERRUN;
+ I915_WRITE(GEN8_DE_PIPE_IMR(pipe), dev_priv->de_irq_mask[pipe]);
+ POSTING_READ(GEN8_DE_PIPE_IMR(pipe));
+}
+
/**
* ibx_display_interrupt_update - update SDEIMR
* @dev_priv: driver private
@@ -382,6 +397,8 @@ bool intel_set_cpu_fifo_underrun_reporting(struct drm_device *dev,
ironlake_set_fifo_underrun_reporting(dev, pipe, enable);
else if (IS_GEN7(dev))
ivybridge_set_fifo_underrun_reporting(dev, pipe, enable);
+ else if (IS_GEN8(dev))
+ broadwell_set_fifo_underrun_reporting(dev, pipe, enable);

done:
spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
@@ -1811,6 +1828,13 @@ static irqreturn_t gen8_irq_handler(int irq, void *arg)
if (pipe_iir & GEN8_PIPE_CDCLK_CRC_DONE)
hsw_pipe_crc_irq_handler(dev, pipe);

+ if (pipe_iir & GEN8_PIPE_FIFO_UNDERRUN) {
+ if (intel_set_cpu_fifo_underrun_reporting(dev, pipe,
+ false))
+ DRM_DEBUG_DRIVER("Pipe %c FIFO underrun\n",
+ pipe_name(pipe));
+ }
+
if (pipe_iir & GEN8_DE_PIPE_IRQ_FAULT_ERRORS) {
DRM_ERROR("Fault errors on pipe %c\n: 0x%08x",
pipe_name(pipe),
@@ -2896,6 +2920,7 @@ static void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
uint32_t de_pipe_enables = GEN8_PIPE_FLIP_DONE |
GEN8_PIPE_VBLANK |
GEN8_PIPE_CDCLK_CRC_DONE |
+ GEN8_PIPE_FIFO_UNDERRUN |
GEN8_DE_PIPE_IRQ_FAULT_ERRORS;
int pipe;
dev_priv->de_irq_mask[PIPE_A] = ~de_pipe_enables;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index fe8cb4c..40fe67b 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4053,7 +4053,7 @@
#define GEN8_DE_PIPE_IMR(pipe) (0x44404 + (0x10 * (pipe)))
#define GEN8_DE_PIPE_IIR(pipe) (0x44408 + (0x10 * (pipe)))
#define GEN8_DE_PIPE_IER(pipe) (0x4440c + (0x10 * (pipe)))
-#define GEN8_PIPE_UNDERRUN (1 << 31)
+#define GEN8_PIPE_FIFO_UNDERRUN (1 << 31)
#define GEN8_PIPE_CDCLK_CRC_ERROR (1 << 29)
#define GEN8_PIPE_CDCLK_CRC_DONE (1 << 28)
#define GEN8_PIPE_CURSOR_FAULT (1 << 10)
--
1.8.4.2