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/r300.c b/drivers/gpu/drm/radeon/r300.c
index 6d75f81..63fe275 100644
--- a/drivers/gpu/drm/radeon/r300.c
+++ b/drivers/gpu/drm/radeon/r300.c
@@ -482,6 +482,7 @@
 	radeon_vram_location(rdev, &rdev->mc, base);
 	if (!(rdev->flags & RADEON_IS_AGP))
 		radeon_gtt_location(rdev, &rdev->mc);
+	radeon_update_bandwidth_info(rdev);
 }
 
 void rv370_set_pcie_lanes(struct radeon_device *rdev, int lanes)