drm/i915: allow stolen, pre-allocated objects to avoid GTT allocation v2

In some cases, we may not need GTT address space allocated to a stolen
object, so allow passing -1 to the preallocated function to indicate as
much.

v2: remove BUG_ON(gtt_offset & 4095) now that -1 is allowed (Ville)

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 913994cd0a3a..89cbfab9570e 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -339,7 +339,6 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 
         /* KISS and expect everything to be page-aligned */
         BUG_ON(stolen_offset & 4095);
-        BUG_ON(gtt_offset & 4095);
         BUG_ON(size & 4095);
 
         if (WARN_ON(size == 0))
@@ -360,6 +359,10 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
                 return NULL;
         }
 
+        /* Some objects just need physical mem from stolen space */
+        if (gtt_offset == -1)
+                return obj;
+
         /* To simplify the initialisation sequence between KMS and GTT,
          * we allow construction of the stolen object prior to
          * setting up the GTT space. The actual reservation will occur