drm/nouveau/fb/ram/mcp77: use carveout reg to determine size

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/subdev/fb/ramnvaa.c

@@ -44,16 +44,15 @@ nvaa_ram_ctor(struct nouveau_object *parent, struct nouveau_object *engine,
 	if (ret)
 		return ret;
 
-	priv->base.size = nv_rd32(pfb, 0x10020c);
-	priv->base.size = (priv->base.size & 0xffffff00) | ((priv->base.size & 0x000000ff) << 32);
+	priv->base.type   = NV_MEM_TYPE_STOLEN;
+	priv->base.stolen = (u64)nv_rd32(pfb, 0x100e10) << 12;
+	priv->base.size   = (u64)nv_rd32(pfb, 0x100e14) << 12;
 
 	ret = nouveau_mm_init(&pfb->vram, rsvd_head, (priv->base.size >> 12) -
 			      (rsvd_head + rsvd_tail), 1);
 	if (ret)
 		return ret;
 
-	priv->base.type   = NV_MEM_TYPE_STOLEN;
-	priv->base.stolen = (u64)nv_rd32(pfb, 0x100e10) << 12;
 	priv->base.get = nv50_ram_get;
 	priv->base.put = nv50_ram_put;
 	return 0;