drm/nv50/fb: prevent oops on chipsets without compression tags

Unconditionally create the tagram mm, even if there's zero tags.

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

diff --git a/drivers/gpu/drm/nouveau/core/subdev/fb/nv50.c b/drivers/gpu/drm/nouveau/core/subdev/fb/nv50.c
index 27fb1af..5f57080 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/subdev/fb/nv50.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/fb/nv50.c
@@ -219,13 +219,11 @@ nv50_fb_ctor(struct nouveau_object *parent, struct nouveau_object *engine,
                             ((priv->base.ram.size & 0x000000ff) << 32);
 
        tags = nv_rd32(priv, 0x100320);
-       if (tags) {
-               ret = nouveau_mm_init(&priv->base.tags, 0, tags, 1);
-               if (ret)
-                       return ret;
+       ret = nouveau_mm_init(&priv->base.tags, 0, tags, 1);
+       if (ret)
+               return ret;
 
-               nv_debug(priv, "%d compression tags\n", tags);
-       }
+       nv_debug(priv, "%d compression tags\n", tags);
 
        size = (priv->base.ram.size >> 12) - rsvd_head - rsvd_tail;
        switch (device->chipset) {