Comment 24 for bug 19711

(In reply to comment #17)
> Your workflow looks good (for extra paranoia, you may want to stick a DRM_INFO
> with the added RADEON_WRITEs and verify that it appears in the kernel output),
> so this rules out the CP writeback as the source of the problem.
>

O.K. I also checked radeon_cp.c that it really contains

       if (radeon_no_wb == 1) {
                dev_priv->writeback_works = 0;
                DRM_INFO("writeback forced off\n");
        }

        if (!dev_priv->writeback_works) {
                /* Disable writeback to avoid unnecessary bus master transfers *
/
                RADEON_WRITE(RADEON_CP_RB_CNTL, RADEON_READ(RADEON_CP_RB_CNTL) |
 RADEON_RB_NO_UPDATE);
                RADEON_WRITE(RADEON_SCRATCH_UMSK, 0);
        }
}

after the patch and it does. Furthermore it seems to be clear that the new
module is loaded as the old one was "1.24.0 20060225". I'm just wondering
because of the kernel oops at unloading...

So as this rules out CP writebacks for increased bus mastering activity, do you
have other ideas?

> BTW, what's the unit of the latency values in /proc/acpi/processor/CPU0/power?

I think they are milliseconds, but don't take that for granted. I'm not sure...