drm/i915: Propagate errors from writing to ringbuffer
Preparing the ringbuffer for adding new commands can fail (a timeout
whilst waiting for the GPU to catch up and free some space). So check
for any potential error before overwriting HEAD with new commands, and
propagate that error back to the user where possible.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 990f065..eb4c725 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5090,22 +5090,16 @@
if (ret)
goto cleanup_objs;
- /* Block clients from rendering to the new back buffer until
- * the flip occurs and the object is no longer visible.
- */
- atomic_add(1 << intel_crtc->plane,
- &to_intel_bo(work->old_fb_obj)->pending_flip);
-
- work->pending_flip_obj = obj;
- obj_priv = to_intel_bo(obj);
-
if (IS_GEN3(dev) || IS_GEN2(dev)) {
u32 flip_mask;
/* Can't queue multiple flips, so wait for the previous
* one to finish before executing the next.
*/
- BEGIN_LP_RING(2);
+ ret = BEGIN_LP_RING(2);
+ if (ret)
+ goto cleanup_objs;
+
if (intel_crtc->plane)
flip_mask = MI_WAIT_FOR_PLANE_B_FLIP;
else
@@ -5115,13 +5109,25 @@
ADVANCE_LP_RING();
}
+ work->pending_flip_obj = obj;
+ obj_priv = to_intel_bo(obj);
+
work->enable_stall_check = true;
/* Offset into the new buffer for cases of shared fbs between CRTCs */
offset = crtc->y * fb->pitch + crtc->x * fb->bits_per_pixel/8;
- BEGIN_LP_RING(4);
- switch(INTEL_INFO(dev)->gen) {
+ ret = BEGIN_LP_RING(4);
+ if (ret)
+ goto cleanup_objs;
+
+ /* Block clients from rendering to the new back buffer until
+ * the flip occurs and the object is no longer visible.
+ */
+ atomic_add(1 << intel_crtc->plane,
+ &to_intel_bo(work->old_fb_obj)->pending_flip);
+
+ switch (INTEL_INFO(dev)->gen) {
case 2:
OUT_RING(MI_DISPLAY_FLIP |
MI_DISPLAY_FLIP_PLANE(intel_crtc->plane));
@@ -5850,16 +5856,17 @@
struct drm_i915_gem_object *obj_priv;
obj_priv = to_intel_bo(dev_priv->renderctx);
if (obj_priv) {
- BEGIN_LP_RING(4);
- OUT_RING(MI_SET_CONTEXT);
- OUT_RING(obj_priv->gtt_offset |
- MI_MM_SPACE_GTT |
- MI_SAVE_EXT_STATE_EN |
- MI_RESTORE_EXT_STATE_EN |
- MI_RESTORE_INHIBIT);
- OUT_RING(MI_NOOP);
- OUT_RING(MI_FLUSH);
- ADVANCE_LP_RING();
+ if (BEGIN_LP_RING(4) == 0) {
+ OUT_RING(MI_SET_CONTEXT);
+ OUT_RING(obj_priv->gtt_offset |
+ MI_MM_SPACE_GTT |
+ MI_SAVE_EXT_STATE_EN |
+ MI_RESTORE_EXT_STATE_EN |
+ MI_RESTORE_INHIBIT);
+ OUT_RING(MI_NOOP);
+ OUT_RING(MI_FLUSH);
+ ADVANCE_LP_RING();
+ }
}
} else
DRM_DEBUG_KMS("Failed to allocate render context."