drm/radeon/kms: display watermark fixes

- rs780/880 were using the wrong bandwidth functions
- convert r1xx-r4xx to use the same pm sclk/mclk structs as
r5xx+
- move bandwidth setup to a common function

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index db78d93..647a0ef 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -437,7 +437,6 @@
 
 int evergreen_mc_init(struct radeon_device *rdev)
 {
-	fixed20_12 a;
 	u32 tmp;
 	int chansize, numchan;
 
@@ -482,12 +481,8 @@
 		rdev->mc.real_vram_size = rdev->mc.aper_size;
 	}
 	r600_vram_gtt_location(rdev, &rdev->mc);
-	/* FIXME: we should enforce default clock in case GPU is not in
-	 * default setup
-	 */
-	a.full = rfixed_const(100);
-	rdev->pm.sclk.full = rfixed_const(rdev->clock.default_sclk);
-	rdev->pm.sclk.full = rfixed_div(rdev->pm.sclk, a);
+	radeon_update_bandwidth_info(rdev);
+
 	return 0;
 }