diff options
| -rw-r--r-- | drivers/char/drm/radeon_cp.c | 7 | ||||
| -rw-r--r-- | drivers/char/drm/radeon_drv.h | 1 |
2 files changed, 8 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 */ diff --git a/drivers/char/drm/radeon_drv.h b/drivers/char/drm/radeon_drv.h index e5a256f5429..b54b8967dcd 100644 --- a/drivers/char/drm/radeon_drv.h +++ b/drivers/char/drm/radeon_drv.h @@ -681,6 +681,7 @@ extern int r300_do_cp_cmdbuf(drm_device_t * dev, DRMFILE filp, #define RADEON_CP_RB_BASE 0x0700 #define RADEON_CP_RB_CNTL 0x0704 # define RADEON_BUF_SWAP_32BIT (2 << 16) +# define RADEON_RB_NO_UPDATE (1 << 27) #define RADEON_CP_RB_RPTR_ADDR 0x070c #define RADEON_CP_RB_RPTR 0x0710 #define RADEON_CP_RB_WPTR 0x0714 |