1 files changed, 83 insertions, 0 deletions
diff --git a/src/gallium/winsys/i915/drm/i915_drm_fence.c b/src/gallium/winsys/i915/drm/i915_drm_fence.c
new file mode 100644
index 0000000000..30ebf4835e
--- /dev/null
+++ b/src/gallium/winsys/i915/drm/i915_drm_fence.c
@@ -0,0 +1,83 @@
+
+#include "i915_drm_winsys.h"
+#include "util/u_memory.h"
+#include "util/u_atomic.h"
+#include "util/u_inlines.h"
+
+/**
+ * Because gem does not have fence's we have to create our own fences.
+ *
+ * They work by keeping the batchbuffer around and checking if that has
+ * been idled. If bo is NULL fence has expired.
+ */
+struct i915_drm_fence
+{
+   struct pipe_reference reference;
+   drm_intel_bo *bo;
+};
+
+
+struct pipe_fence_handle *
+i915_drm_fence_create(drm_intel_bo *bo)
+{
+   struct i915_drm_fence *fence = CALLOC_STRUCT(i915_drm_fence);
+
+   pipe_reference_init(&fence->reference, 1);
+   /* bo is null if fence already expired */
+   if (bo) {
+      drm_intel_bo_reference(bo);
+      fence->bo = bo;
+   }
+
+   return (struct pipe_fence_handle *)fence;
+}
+
+static void
+i915_drm_fence_reference(struct i915_winsys *iws,
+                          struct pipe_fence_handle **ptr,
+                          struct pipe_fence_handle *fence)
+{
+   struct i915_drm_fence *old = (struct i915_drm_fence *)*ptr;
+   struct i915_drm_fence *f = (struct i915_drm_fence *)fence;
+
+   if (pipe_reference(&((struct i915_drm_fence *)(*ptr))->reference, &f->reference)) {
+      if (old->bo)
+         drm_intel_bo_unreference(old->bo);
+      FREE(old);
+   }
+   *ptr = fence;
+}
+
+static int
+i915_drm_fence_signalled(struct i915_winsys *iws,
+                          struct pipe_fence_handle *fence)
+{
+   assert(0);
+
+   return 0;
+}
+
+static int
+i915_drm_fence_finish(struct i915_winsys *iws,
+                       struct pipe_fence_handle *fence)
+{
+   struct i915_drm_fence *f = (struct i915_drm_fence *)fence;
+
+   /* fence already expired */
+   if (!f->bo)
+      return 0;
+
+   drm_intel_bo_wait_rendering(f->bo);
+   drm_intel_bo_unreference(f->bo);
+   f->bo = NULL;
+
+   return 0;
+}
+
+void
+i915_drm_winsys_init_fence_functions(struct i915_drm_winsys *idws)
+{
+   idws->base.fence_reference = i915_drm_fence_reference;
+   idws->base.fence_signalled = i915_drm_fence_signalled;
+   idws->base.fence_finish = i915_drm_fence_finish;
+}