drm/radeon/kms: add some loop timeouts in pageflip code
Avoid infinite loops waiting for surface updates if a GPU
reset happens while waiting for a page flip.
See:
https://bugs.freedesktop.org/show_bug.cgi?id=43191
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@kernel.org
Reviewed-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Tested-by: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index ad158ea..bfc08f6 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -187,13 +187,18 @@
{
struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
u32 tmp = ((u32)crtc_base) | RADEON_CRTC_OFFSET__OFFSET_LOCK;
+ int i;
/* Lock the graphics update lock */
/* update the scanout addresses */
WREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset, tmp);
/* Wait for update_pending to go high. */
- while (!(RREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset) & RADEON_CRTC_OFFSET__GUI_TRIG_OFFSET));
+ for (i = 0; i < rdev->usec_timeout; i++) {
+ if (RREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset) & RADEON_CRTC_OFFSET__GUI_TRIG_OFFSET)
+ break;
+ udelay(1);
+ }
DRM_DEBUG("Update pending now high. Unlocking vupdate_lock.\n");
/* Unlock the lock, so double-buffering can take place inside vblank */