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/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 3630c16..df7a855 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -475,8 +475,10 @@
 	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
 	base = RREG32_MC(R_000004_MC_FB_LOCATION);
 	base = G_000004_MC_FB_START(base) << 16;
+	rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev);
 	radeon_vram_location(rdev, &rdev->mc, base);
 	radeon_gtt_location(rdev, &rdev->mc);
+	radeon_update_bandwidth_info(rdev);
 }
 
 void rs600_bandwidth_update(struct radeon_device *rdev)