[PATCH 09/10] drm/i915: print CPU FIFO underruns

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

Just like the PCH FIFO underruns, except that there's no place
where we expect it to happen.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h      |    2 ++
 drivers/gpu/drm/i915/i915_irq.c      |   33 ++++++++++++++++++++++++++++++++-
 drivers/gpu/drm/i915/i915_reg.h      |    3 +++
 drivers/gpu/drm/i915/intel_display.c |    2 ++
 4 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e96d75e..f614ea8 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -909,6 +909,8 @@ typedef struct drm_i915_private {
 	struct work_struct hotplug_work;
 	bool enable_hotplug_processing;
 
+	/* Bit 0: pipe A and son on. */
+	u8 ignore_cpu_fifo_underrun;
 	/* Bit 0: PCH transcoder A and so on. */
 	u8 ignore_pch_fifo_underrun;
 
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 7497589..09bd8d4 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -680,6 +680,24 @@ static void err_int_handler(struct drm_device *dev)
 	if (err_int & ERR_INT_POISON)
 		DRM_ERROR("Poison interrupt\n");
 
+	if ((err_int & ERR_INT_FIFO_UNDERRUN_A) &&
+	    !(dev_priv->ignore_cpu_fifo_underrun & (1 << PIPE_A))) {
+		DRM_ERROR("Pipe A FIFO underrun\n");
+		dev_priv->ignore_cpu_fifo_underrun |= (1 << PIPE_A);
+	}
+
+	if ((err_int & ERR_INT_FIFO_UNDERRUN_B) &&
+	    !(dev_priv->ignore_cpu_fifo_underrun & (1 << PIPE_B))) {
+		DRM_ERROR("Pipe B FIFO underrun\n");
+		dev_priv->ignore_cpu_fifo_underrun |= (1 << PIPE_B);
+	}
+
+	if ((err_int & ERR_INT_FIFO_UNDERRUN_C) &&
+	    !(dev_priv->ignore_cpu_fifo_underrun & (1 << PIPE_C))) {
+		DRM_ERROR("Pipe C FIFO underrun\n");
+		dev_priv->ignore_cpu_fifo_underrun |= (1 << PIPE_C);
+	}
+
 	I915_WRITE(GEN7_ERR_INT, err_int);
 }
 
@@ -901,6 +919,18 @@ static irqreturn_t ironlake_irq_handler(int irq, void *arg)
 	if (de_iir & DE_POISON)
 		DRM_ERROR("Poison interrupt\n");
 
+	if ((de_iir & DE_PIPEA_FIFO_UNDERRUN) &&
+	    !(dev_priv->ignore_cpu_fifo_underrun & (1 << PIPE_A))) {
+		DRM_ERROR("Pipe A FIFO underrun\n");
+		dev_priv->ignore_cpu_fifo_underrun |= (1 << PIPE_A);
+	}
+
+	if ((de_iir & DE_PIPEB_FIFO_UNDERRUN) &&
+	    !(dev_priv->ignore_cpu_fifo_underrun & (1 << PIPE_B))) {
+		DRM_ERROR("Pipe B FIFO underrun\n");
+		dev_priv->ignore_cpu_fifo_underrun |= (1 << PIPE_B);
+	}
+
 	if (de_iir & DE_PLANEA_FLIP_DONE) {
 		intel_prepare_page_flip(dev, 0);
 		intel_finish_page_flip_plane(dev, 0);
@@ -2051,7 +2081,8 @@ static int ironlake_irq_postinstall(struct drm_device *dev)
 	/* enable kind of interrupts always enabled */
 	u32 display_mask = DE_MASTER_IRQ_CONTROL | DE_GSE | DE_PCH_EVENT |
 			   DE_PLANEA_FLIP_DONE | DE_PLANEB_FLIP_DONE |
-			   DE_AUX_CHANNEL_A | DE_POISON;
+			   DE_AUX_CHANNEL_A | DE_POISON |
+			   DE_PIPEB_FIFO_UNDERRUN | DE_PIPEA_FIFO_UNDERRUN;
 	u32 render_irqs;
 
 	dev_priv->irq_mask = ~display_mask;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index d565bd7..c0db8b4 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -521,6 +521,9 @@
 #define GEN7_ERR_INT	0x44040
 #define   ERR_INT_POISON		(1<<31)
 #define   ERR_INT_MMIO_UNCLAIMED	(1<<13)
+#define   ERR_INT_FIFO_UNDERRUN_C	(1<<6)
+#define   ERR_INT_FIFO_UNDERRUN_B	(1<<3)
+#define   ERR_INT_FIFO_UNDERRUN_A	(1<<0)
 
 #define FPGA_DBG		0x42300
 #define FPGA_DBG_RM_NOCLAIM	(1<<31)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 67bfb58..030a8d3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3275,6 +3275,7 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 
 	intel_crtc->active = true;
 
+	dev_priv->ignore_cpu_fifo_underrun &= ~(1 << pipe);
 	dev_priv->ignore_pch_fifo_underrun &= ~(1 << pipe);
 
 	intel_update_watermarks(dev);
@@ -3372,6 +3373,7 @@ static void haswell_crtc_enable(struct drm_crtc *crtc)
 
 	is_pch_port = haswell_crtc_driving_pch(crtc);
 
+	dev_priv->ignore_cpu_fifo_underrun &= ~(1 << pipe);
 	if (is_pch_port)
 		dev_priv->ignore_pch_fifo_underrun &= ~(1 << TRANSCODER_A);
 
-- 
1.7.10.4