[Intel-gfx] [PATCH 19/49] drm/i915: Record ring->start address in error state

[Chris Wilson]

This is mostly useful for execlists where the rings switch between
contexts (and so checking that the ring's start register matches the
context is important).

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_drv.h       |  1 +
 drivers/gpu/drm/i915/i915_gpu_error.c | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 7cf5d1b0a749..68a50891830f 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -455,6 +455,7 @@ struct drm_i915_error_state {
 		u32 semaphore_seqno[I915_NUM_RINGS - 1];
 
 		/* Register state */
+		u32 start;
 		u32 tail;
 		u32 head;
 		u32 ctl;
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 5f798961266f..17dc2fcaba10 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -256,10 +256,11 @@ static void i915_ring_error_state(struct drm_i915_error_state_buf *m,
 		return;
 
 	err_printf(m, "%s command stream:\n", ring_str(ring_idx));
-	err_printf(m, "  HEAD: 0x%08x\n", ring->head);
-	err_printf(m, "  TAIL: 0x%08x\n", ring->tail);
-	err_printf(m, "  CTL: 0x%08x\n", ring->ctl);
-	err_printf(m, "  HWS: 0x%08x\n", ring->hws);
+	err_printf(m, "  START: 0x%08x\n", ring->start);
+	err_printf(m, "  HEAD:  0x%08x\n", ring->head);
+	err_printf(m, "  TAIL:  0x%08x\n", ring->tail);
+	err_printf(m, "  CTL:   0x%08x\n", ring->ctl);
+	err_printf(m, "  HWS:   0x%08x\n", ring->hws);
 	err_printf(m, "  ACTHD: 0x%08x %08x\n", (u32)(ring->acthd>>32), (u32)ring->acthd);
 	err_printf(m, "  IPEIR: 0x%08x\n", ring->ipeir);
 	err_printf(m, "  IPEHR: 0x%08x\n", ring->ipehr);
@@ -890,6 +891,7 @@ static void i915_record_ring_state(struct drm_device *dev,
 	ering->instpm = I915_READ(RING_INSTPM(ring->mmio_base));
 	ering->seqno = ring->get_seqno(ring, false);
 	ering->acthd = intel_ring_get_active_head(ring);
+	ering->start = I915_READ_START(ring);
 	ering->head = I915_READ_HEAD(ring);
 	ering->tail = I915_READ_TAIL(ring);
 	ering->ctl = I915_READ_CTL(ring);
-- 
2.1.4