drm/radeon/kms: add sanity check to wptr.
If we resume in a bad way, we'll get 0xffffffff in wptr, and then
oops with no console. This just adds a sanity check so that we can
avoid the oops and hopefully get more details out of people's systems.
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 138ddd4..c8f4b03 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -744,6 +744,8 @@
udelay(10);
rdev->cp.rptr = RREG32(RADEON_CP_RB_RPTR);
rdev->cp.wptr = RREG32(RADEON_CP_RB_WPTR);
+ /* protect against crazy HW on resume */
+ rdev->cp.wptr &= rdev->cp.ptr_mask;
/* Set cp mode to bus mastering & enable cp*/
WREG32(RADEON_CP_CSQ_MODE,
REG_SET(RADEON_INDIRECT2_START, indirect2_start) |