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diff --git a/lib/librte_hash/rte_hash_crc.h b/lib/librte_hash/rte_hash_crc.h
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+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+#ifndef _RTE_HASH_CRC_H_
+#define _RTE_HASH_CRC_H_
+
+/**
+ * @file
+ *
+ * RTE CRC Hash
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+/**
+ * Use single crc32 instruction to perform a hash on a 4 byte value.
+ *
+ * @param data
+ * Data to perform hash on.
+ * @param init_val
+ * Value to initialise hash generator.
+ * @return
+ * 32bit calculated hash value.
+ */
+static inline uint32_t
+rte_hash_crc_4byte(uint32_t data, uint32_t init_val)
+{
+ asm volatile("crc32 %[data], %[init_val]"
+ : [init_val]"=r" (init_val)
+ : [data]"r" (data), "[init_val]" (init_val));
+ return init_val;
+}
+
+/**
+ * Use crc32 instruction to perform a hash.
+ *
+ * @param data
+ * Data to perform hash on.
+ * @param data_len
+ * How many bytes to use to calculate hash value.
+ * @param init_val
+ * Value to initialise hash generator.
+ * @return
+ * 32bit calculated hash value.
+ */
+static inline uint32_t
+rte_hash_crc(const void *data, uint32_t data_len, uint32_t init_val)
+{
+ unsigned i;
+ uint32_t temp = 0;
+ const uint32_t *p32 = (const uint32_t *)data;
+
+ for (i = 0; i < data_len / 4; i++) {
+ init_val = rte_hash_crc_4byte(*p32++, init_val);
+ }
+
+ switch (3 - (data_len & 0x03)) {
+ case 0:
+ temp |= *((const uint8_t *)p32 + 2) << 16;
+ /* Fallthrough */
+ case 1:
+ temp |= *((const uint8_t *)p32 + 1) << 8;
+ /* Fallthrough */
+ case 2:
+ temp |= *((const uint8_t *)p32);
+ init_val = rte_hash_crc_4byte(temp, init_val);
+ default:
+ break;
+ }
+
+ return init_val;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_HASH_CRC_H_ */