On Die, 2011-08-09 at 23:52 +0530, Mayank Rungta wrote: > Added a check for the radeon ring buffer write index in r600.c which > reads 0xffffffff on resume. This results in an Oops during > radeon_ring_write. Masking the value averts this. > > This problem is not seen to be fixed in 3.0 r600.c as well. > > Detailed analysis of the problem can be found at - > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/820746/ > > --- > > BUG: unable to handle kernel paging request at fa501ffc - Oops at > r600_cp_start+0x48/0x380 in r600_cp_resume+0x345/0x580 [radeon] > > drivers/gpu/drm/radeon/r600.c > > > > --- linux-2.6.38/drivers/gpu/drm/radeon/r600.c.orig 2011-08-05 > 15:39:40.824612700 +0530 > +++ linux-2.6.38/drivers/gpu/drm/radeon/r600.c 2011-08-08 > 05:29:21.744417857 +0530 > @@ -2218,6 +2218,8 @@ int r600_cp_resume(struct radeon_device > > rdev->cp.rptr = RREG32(CP_RB_RPTR); > rdev->cp.wptr = RREG32(CP_RB_WPTR); > + /* protect against crazy HW on resume */ > + rdev->cp.wptr &= rdev->cp.ptr_mask; The indentation of the lines you're adding doesn't match the surrounding lines. Although the same workaround is already in r100.c, I wonder if we shouldn't rather try and eliminate all reads from the CP_RB_WPTR register, at least other than for debugging purposes. Alex, what do you think? Otherwise, this should probably be added in evergreen.c as well. > Developer's Certificate of Origin 1.1 > > [...] No need to include all this text, just the *-by: tags are enough. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Debian, X and DRI developer _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
