agp/intel-gtt: export the scratch page dma address

To implement a PPGTT for drm/i915 that fully aliases the GTT, we also
need to properly alias the scratch page.

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/drm/intel-gtt.h b/include/drm/intel-gtt.h
index b174620cc9b3..6d4c77ac7d76 100644
--- a/include/drm/intel-gtt.h
+++ b/include/drm/intel-gtt.h
@@ -15,6 +15,8 @@ const struct intel_gtt {
         unsigned int needs_dmar : 1;
         /* Whether we idle the gpu before mapping/unmapping */
         unsigned int do_idle_maps : 1;
+        /* Share the scratch page dma with ppgtts. */
+        dma_addr_t scratch_page_dma;
 } *intel_gtt_get(void);
 
 void intel_gtt_chipset_flush(void);