drm/radeon/kms: clean up some magic numbers

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 5968dde..5f15820 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -1031,8 +1031,8 @@
 	WREG32(RADEON_CP_CSQ_MODE,
 	       REG_SET(RADEON_INDIRECT2_START, indirect2_start) |
 	       REG_SET(RADEON_INDIRECT1_START, indirect1_start));
-	WREG32(0x718, 0);
-	WREG32(0x744, 0x00004D4D);
+	WREG32(RADEON_CP_RB_WPTR_DELAY, 0);
+	WREG32(RADEON_CP_CSQ_MODE, 0x00004D4D);
 	WREG32(RADEON_CP_CSQ_CNTL, RADEON_CSQ_PRIBM_INDBM);
 	radeon_ring_start(rdev);
 	r = radeon_ring_test(rdev);
@@ -2347,10 +2347,10 @@
 
 	temp = RREG32(RADEON_CONFIG_CNTL);
 	if (state == false) {
-		temp &= ~(1<<8);
-		temp |= (1<<9);
+		temp &= ~RADEON_CFG_VGA_RAM_EN;
+		temp |= RADEON_CFG_VGA_IO_DIS;
 	} else {
-		temp &= ~(1<<9);
+		temp &= ~RADEON_CFG_VGA_IO_DIS;
 	}
 	WREG32(RADEON_CONFIG_CNTL, temp);
 }