drm/i915: Capture batchbuffer state upon GPU hang

The bbstate contains useful bits of debugging information such as
whether the batch is being read from GTT or PPGTT, or whether it is
allowed to execute privileged instructions.

v2: Only record BB_STATE for gen4+

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 57715c8e59c6..8bc0b3b42183 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -299,6 +299,7 @@ struct drm_i915_error_state {
         u32 cpu_ring_tail[I915_NUM_RINGS];
         u32 error; /* gen6+ */
         u32 err_int; /* gen7 */
+        u32 bbstate[I915_NUM_RINGS];
         u32 instpm[I915_NUM_RINGS];
         u32 instps[I915_NUM_RINGS];
         u32 extra_instdone[I915_NUM_INSTDONE_REG];
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 5dde81026471..a8bb213da79f 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -249,7 +249,8 @@ static void i915_ring_error_state(struct drm_i915_error_state_buf *m,
         err_printf(m, "  INSTDONE: 0x%08x\n", error->instdone[ring]);
         if (ring == RCS && INTEL_INFO(dev)->gen >= 4)
                 err_printf(m, "  BBADDR: 0x%08llx\n", error->bbaddr);
-
+        if (INTEL_INFO(dev)->gen >= 4)
+                err_printf(m, "  BB_STATE: 0x%08x\n", error->bbstate[ring]);
         if (INTEL_INFO(dev)->gen >= 4)
                 err_printf(m, "  INSTPS: 0x%08x\n", error->instps[ring]);
         err_printf(m, "  INSTPM: 0x%08x\n", error->instpm[ring]);
@@ -725,6 +726,7 @@ static void i915_record_ring_state(struct drm_device *dev,
                 error->instps[ring->id] = I915_READ(RING_INSTPS(ring->mmio_base));
                 if (ring->id == RCS)
                         error->bbaddr = I915_READ64(BB_ADDR);
+                error->bbstate[ring->id] = I915_READ(RING_BBSTATE(ring->mmio_base));
         } else {
                 error->faddr[ring->id] = I915_READ(DMA_FADD_I8XX);
                 error->ipeir[ring->id] = I915_READ(IPEIR);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 47de41f1d4b4..9785f7d031a4 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -718,6 +718,7 @@
 #define NOPID           0x02094
 #define HWSTAM          0x02098
 #define DMA_FADD_I8XX   0x020d0
+#define RING_BBSTATE(base)      ((base)+0x110)
 
 #define ERROR_GEN6      0x040a0
 #define GEN7_ERR_INT    0x44040