diff options
Diffstat (limited to 'drivers/char/drm/radeon_cp.c')
-rw-r--r-- | drivers/char/drm/radeon_cp.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/char/drm/radeon_cp.c b/drivers/char/drm/radeon_cp.c index 5ad43ba7b5a..3956628b257 100644 --- a/drivers/char/drm/radeon_cp.c +++ b/drivers/char/drm/radeon_cp.c @@ -1258,6 +1258,13 @@ static void radeon_test_writeback(drm_radeon_private_t * dev_priv) dev_priv->writeback_works = 0; DRM_INFO("writeback forced off\n"); } + + if (!dev_priv->writeback_works) { + /* Disable writeback to avoid unnecessary bus master transfer */ + RADEON_WRITE(RADEON_CP_RB_CNTL, RADEON_READ(RADEON_CP_RB_CNTL) | + RADEON_RB_NO_UPDATE); + RADEON_WRITE(RADEON_SCRATCH_UMSK, 0); + } } /* Enable or disable PCI-E GART on the chip */ |