a-r-karthick: thanks for your analysis. This invalid register read seems something very similar which was also workarounded at r100_cp_init function, take a look at this change:
commit 9e5786bd14cb9ffe29ebe66d41cedf03311b0d30 Author: Dave Airlie <[email protected]> Date: Wed Mar 31 13:38:56 2010 +1000 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 <[email protected]> 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 @@ int r100_cp_init(struct radeon_device *rdev, unsigned ring_size) 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) | a-r-karthick: Can you raise this issue upstream, at [email protected] mailing list? You can just test and send a similar patch for review, using ptr_mask also. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/820746 Title: Black screen on boot - Oops: 0002 [#1] SMP on Lenovo T400 laptop with radeon To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/820746/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
