Merge tag 'drm-intel-fixes-2013-08-23' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes

Just one patch that soaked for quite a bit to fix a resume issue,
resulting in gpu hangs (or worse) due to tlb containing garbage.

* tag 'drm-intel-fixes-2013-08-23' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: Invalidate TLBs for the rings after a reset

2 files changed, 14 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 6f514297c483..53cddd985406 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -752,6 +752,8 @@
                                         will not assert AGPBUSY# and will only
                                         be delivered when out of C3. */
 #define   INSTPM_FORCE_ORDERING                         (1<<7) /* GEN6+ */
+#define   INSTPM_TLB_INVALIDATE (1<<9)
+#define   INSTPM_SYNC_FLUSH     (1<<5)
 #define ACTHD           0x020c8
 #define FW_BLC          0x020d8
 #define FW_BLC2         0x020dc
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 664118d8c1d6..079ef0129e74 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -968,6 +968,18 @@ void intel_ring_setup_status_page(struct intel_ring_buffer *ring)
 
         I915_WRITE(mmio, (u32)ring->status_page.gfx_addr);
         POSTING_READ(mmio);
+
+        /* Flush the TLB for this page */
+        if (INTEL_INFO(dev)->gen >= 6) {
+                u32 reg = RING_INSTPM(ring->mmio_base);
+                I915_WRITE(reg,
+                           _MASKED_BIT_ENABLE(INSTPM_TLB_INVALIDATE |
+                                              INSTPM_SYNC_FLUSH));
+                if (wait_for((I915_READ(reg) & INSTPM_SYNC_FLUSH) == 0,
+                             1000))
+                        DRM_ERROR("%s: wait for SyncFlush to complete for TLB invalidation timed out\n",
+                                  ring->name);
+        }
 }
 
 static int