Initial commit.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

include/sbi/riscv_atomic.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2018 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#ifndef __RISCV_ATOMIC_H__
+#define __RISCV_ATOMIC_H__
+
+typedef struct {
+	volatile long counter;
+} atomic_t;
+
+#define ATOMIC_INIT(_lptr, val)		\
+	(_lptr)->counter = (val)
+
+#define ATOMIC_INITIALIZER(val)		\
+	{ .counter = (val), }
+
+long atomic_read(atomic_t *atom);
+
+void atomic_write(atomic_t *atom, long value);
+
+long atomic_add_return(atomic_t *atom, long value);
+
+long atomic_sub_return(atomic_t *atom, long value);
+
+long arch_atomic_cmpxchg(atomic_t *atom, long oldval, long newval);
+
+long arch_atomic_xchg(atomic_t *atom, long newval);
+
+unsigned int atomic_raw_xchg_uint(volatile unsigned int *ptr,
+				  unsigned int newval);
+
+#endif