} else
 #endif
        {
-               struct drm_sg_mem *entry = dev->sg;
-               unsigned long tmp_ofs, page_ofs;
-
-               tmp_ofs = dev_priv->ring_rptr->offset -
-                               (unsigned long)dev->sg->virtual;
-               page_ofs = tmp_ofs >> PAGE_SHIFT;
-
-               RADEON_WRITE(RADEON_CP_RB_RPTR_ADDR, entry->busaddr[page_ofs]);
-               DRM_DEBUG("ring rptr: offset=0x%08lx handle=0x%08lx\n",
-                         (unsigned long)entry->busaddr[page_ofs],
-                         entry->handle + tmp_ofs);
+               RADEON_WRITE(RADEON_CP_RB_RPTR_ADDR,
+                            dev_priv->ring_rptr->offset
+                            - ((unsigned long) dev->sg->virtual)
+                            + dev_priv->gart_vm_start);
        }
 
        /* Set ring buffer size */