patches.baytrail/0191-drm-i915-track-ring-progression-using-seqnos.patch

From 9f3f987cb1f2ebc32e2442b63a4b0e75c648f45f Mon Sep 17 00:00:00 2001
From: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Fri, 24 May 2013 17:16:07 +0300
Subject: drm/i915: track ring progression using seqnos

Instead of relying in acthd, track ring seqno progression
to detect if ring has hung.

v2: put hangcheck stuff inside struct (Chris Wilson)

v3: initialize hangcheck.seqno (Ben Widawsky)

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 92cab7345131db7af18f630a799ce6b2e8e624c5)
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h         |    2 --
 drivers/gpu/drm/i915/i915_irq.c         |   30 +++++++++++++-----------------
 drivers/gpu/drm/i915/intel_ringbuffer.c |    1 +
 drivers/gpu/drm/i915/intel_ringbuffer.h |    6 ++++++
 4 files changed, 20 insertions(+), 19 deletions(-)

--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -843,8 +843,6 @@ struct i915_gpu_error {
 #define DRM_I915_HANGCHECK_JIFFIES msecs_to_jiffies(DRM_I915_HANGCHECK_PERIOD)
 	struct timer_list hangcheck_timer;
 	int hangcheck_count;
-	uint32_t last_acthd[I915_NUM_RINGS];
-	uint32_t prev_instdone[I915_NUM_INSTDONE_REG];
 
 	/* For reset and error_state handling. */
 	spinlock_t lock;
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -2421,22 +2421,19 @@ void i915_hangcheck_elapsed(unsigned lon
 {
 	struct drm_device *dev = (struct drm_device *)data;
 	drm_i915_private_t *dev_priv = dev->dev_private;
-	uint32_t acthd[I915_NUM_RINGS], instdone[I915_NUM_INSTDONE_REG];
 	struct intel_ring_buffer *ring;
 	bool err = false, idle;
 	int i;
+	u32 seqno[I915_NUM_RINGS];
+	bool work_done;
 
 	if (!i915_enable_hangcheck)
 		return;
 
-	memset(acthd, 0, sizeof(acthd));
 	idle = true;
 	for_each_ring(ring, dev_priv, i) {
-		u32 seqno;
-
-		seqno = ring->get_seqno(ring, false);
-		idle &= i915_hangcheck_ring_idle(ring, seqno, &err);
-	    acthd[i] = intel_ring_get_active_head(ring);
+		seqno[i] = ring->get_seqno(ring, false);
+		idle &= i915_hangcheck_ring_idle(ring, seqno[i], &err);
 	}
 
 	/* If all work is done then ACTHD clearly hasn't advanced. */
@@ -2452,20 +2449,19 @@ void i915_hangcheck_elapsed(unsigned lon
 		return;
 	}
 
-	i915_get_extra_instdone(dev, instdone);
-	if (memcmp(dev_priv->gpu_error.last_acthd, acthd,
-		   sizeof(acthd)) == 0 &&
-	    memcmp(dev_priv->gpu_error.prev_instdone, instdone,
-		   sizeof(instdone)) == 0) {
+	work_done = false;
+	for_each_ring(ring, dev_priv, i) {
+		if (ring->hangcheck.seqno != seqno[i]) {
+			work_done = true;
+			ring->hangcheck.seqno = seqno[i];
+		}
+	}
+
+	if (!work_done) {
 		if (i915_hangcheck_hung(dev))
 			return;
 	} else {
 		dev_priv->gpu_error.hangcheck_count = 0;
-
-		memcpy(dev_priv->gpu_error.last_acthd, acthd,
-		       sizeof(acthd));
-		memcpy(dev_priv->gpu_error.prev_instdone, instdone,
-		       sizeof(instdone));
 	}
 
 repeat:
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1523,6 +1523,7 @@ void intel_ring_init_seqno(struct intel_
 	}
 
 	ring->set_seqno(ring, seqno);
+	ring->hangcheck.seqno = seqno;
 }
 
 void intel_ring_advance(struct intel_ring_buffer *ring)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -37,6 +37,10 @@ struct  intel_hw_status_page {
 #define I915_READ_SYNC_0(ring) I915_READ(RING_SYNC_0((ring)->mmio_base))
 #define I915_READ_SYNC_1(ring) I915_READ(RING_SYNC_1((ring)->mmio_base))
 
+struct intel_ring_hangcheck {
+	u32 seqno;
+};
+
 struct  intel_ring_buffer {
 	const char	*name;
 	enum intel_ring_id {
@@ -137,6 +141,8 @@ struct  intel_ring_buffer {
 	struct i915_hw_context *default_context;
 	struct i915_hw_context *last_context;
 
+	struct intel_ring_hangcheck hangcheck;
+
 	void *private;
 };