[opensbi] create opensbi from T-Head official:

repo: https://github.com/T-head-Semi/opensbi
	commit: 89182b257c8798e15e4c685c1af0c2862d528d2a

Change-Id: I7b39d66729e0108661a6f4c9e28acbdb303684ea

opensbi/include/sbi/sbi_fifo.h

@@ -0,0 +1,42 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Atish Patra<atish.patra@wdc.com>
+ *
+ */
+
+#ifndef __SBI_FIFO_H__
+#define __SBI_FIFO_H__
+
+#include <sbi/riscv_locks.h>
+#include <sbi/sbi_types.h>
+
+struct sbi_fifo {
+	void *queue;
+	spinlock_t qlock;
+	u16 entry_size;
+	u16 num_entries;
+	u16 avail;
+	u16 tail;
+};
+
+enum sbi_fifo_inplace_update_types {
+	SBI_FIFO_SKIP,
+	SBI_FIFO_UPDATED,
+	SBI_FIFO_UNCHANGED,
+};
+
+int sbi_fifo_dequeue(struct sbi_fifo *fifo, void *data);
+int sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data);
+void sbi_fifo_init(struct sbi_fifo *fifo, void *queue_mem, u16 entries,
+		   u16 entry_size);
+bool sbi_fifo_is_empty(struct sbi_fifo *fifo);
+bool sbi_fifo_is_full(struct sbi_fifo *fifo);
+int sbi_fifo_inplace_update(struct sbi_fifo *fifo, void *in,
+			    int (*fptr)(void *in, void *data));
+u16 sbi_fifo_avail(struct sbi_fifo *fifo);
+
+#endif