Remove unused arch-agnostic instruction barrier.
Add an implementation for the fake architecture used for host unit
tests.
Change-Id: I5ba49b3f0a4ce0199f421f12c3019e3cb7a58b6a
diff --git a/src/arch/aarch64/inc/hf/arch/barriers.h b/src/arch/aarch64/inc/hf/arch/barriers.h
index 85d4e7d..3d61434 100644
--- a/src/arch/aarch64/inc/hf/arch/barriers.h
+++ b/src/arch/aarch64/inc/hf/arch/barriers.h
@@ -62,9 +62,3 @@
* before continuing.
*/
#define data_sync_barrier() dsb(sy)
-
-/**
- * Flushes the instruction pipeline so that instructions are fetched from
- * memory.
- */
-#define insn_sync_barrier() isb()
diff --git a/src/arch/fake/inc/hf/arch/barriers.h b/src/arch/fake/inc/hf/arch/barriers.h
new file mode 100644
index 0000000..46f35a9
--- /dev/null
+++ b/src/arch/fake/inc/hf/arch/barriers.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2019 The Hafnium Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdatomic.h>
+
+/** Platform-agnostic API */
+
+/**
+ * Ensures all explicit memory accesses before this point are completed before
+ * any later memory accesses are performed.
+ */
+#define memory_ordering_barrier() atomic_thread_fence(memory_order_seq_cst)
+
+/**
+ * Ensures all explicit memory access and management instructions have completed
+ * before continuing.
+ *
+ * FIXME: this is just a memory barrier but, without MMIO or registers to modify
+ * operation in the fake architecture, this is likely enough. If there's a way
+ * to have a true synchronization then we should update it.
+ */
+#define data_sync_barrier() atomic_thread_fence(memory_order_seq_cst)
