drm/radeon: add support for MC/VM setup on CIK (v6)

The vm callbacks are the same as the SI ones right now
(same regs and bits). We could share the SI variants, and
I may yet do that, but I figured I would add CIK specific
ones for now in case we need to change anything.

V2: add documentation, minor fixes.
V3: integrate vram offset fixes for APUs
V4: enable 2 level VM PTs
V5: index SH_MEM_* regs properly
V6: add ib_parse()

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index a1b0da6..813a8a9 100644
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -3535,8 +3535,8 @@
 	}
 }
 
-static void si_vram_gtt_location(struct radeon_device *rdev,
-				 struct radeon_mc *mc)
+void si_vram_gtt_location(struct radeon_device *rdev,
+			  struct radeon_mc *mc)
 {
 	if (mc->mc_vram_size > 0xFFC0000000ULL) {
 		/* leave room for at least 1024M GTT */