+ /*
+ * PIPE_CONTROL and MI_* use PPGTT writes on GEN7+ and privileged GGTT
+ * writes on GEN6.
+ *
+ * From the Sandy Bridge PRM, volume 1 part 3, page 101:
+ *
+ * "[DevSNB] When Per-Process GTT Enable is set, it is assumed that all
+ * code is in a secure environment, independent of address space.
+ * Under this condition, this bit only specifies the address space
+ * (GGTT or PPGTT). All commands are executed "as-is""
+ *
+ * We need PPGTT to be enabled on GEN6 too.
+ */
+ if (!dev->has_ppgtt) {
+ /* experiments show that it does not really matter... */
+ ilo_warn("PPGTT disabled\n");
+ }
+