1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
3 */
4
5 #ifndef _RTE_HASH_CRC_H_
6 #define _RTE_HASH_CRC_H_
7
8 /**
9 * @file
10 *
11 * RTE CRC Hash
12 */
13
14 #ifdef __cplusplus
15 extern "C" {
16 #endif
17
18 #include <stdint.h>
19
20 #include <rte_branch_prediction.h>
21 #include <rte_common.h>
22 #include <rte_config.h>
23 #include <rte_cpuflags.h>
24 #include <rte_log.h>
25
26 #include "rte_crc_sw.h"
27
28 #define CRC32_SW (1U << 0)
29 #define CRC32_SSE42 (1U << 1)
30 #define CRC32_x64 (1U << 2)
31 #define CRC32_SSE42_x64 (CRC32_x64|CRC32_SSE42)
32 #define CRC32_ARM64 (1U << 3)
33
34 static uint8_t crc32_alg = CRC32_SW;
35
36 #if defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
37 #include "rte_crc_arm64.h"
38 #elif defined(RTE_ARCH_X86)
39 #include "rte_crc_x86.h"
40 #else
41 #include "rte_crc_generic.h"
42 #endif
43
44 /**
45 * Allow or disallow use of SSE4.2/ARMv8 intrinsics for CRC32 hash
46 * calculation.
47 *
48 * @param alg
49 * An OR of following flags:
50 * - (CRC32_SW) Don't use SSE4.2/ARMv8 intrinsics (default non-[x86/ARMv8])
51 * - (CRC32_SSE42) Use SSE4.2 intrinsics if available
52 * - (CRC32_SSE42_x64) Use 64-bit SSE4.2 intrinsic if available (default x86)
53 * - (CRC32_ARM64) Use ARMv8 CRC intrinsic if available (default ARMv8)
54 *
55 */
56 static inline void
rte_hash_crc_set_alg(uint8_t alg)57 rte_hash_crc_set_alg(uint8_t alg)
58 {
59 crc32_alg = CRC32_SW;
60
61 if (alg == CRC32_SW)
62 return;
63
64 #if defined RTE_ARCH_X86
65 if (!(alg & CRC32_SSE42_x64))
66 RTE_LOG(WARNING, HASH,
67 "Unsupported CRC32 algorithm requested using CRC32_x64/CRC32_SSE42\n");
68 if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_EM64T) || alg == CRC32_SSE42)
69 crc32_alg = CRC32_SSE42;
70 else
71 crc32_alg = CRC32_SSE42_x64;
72 #endif
73
74 #if defined RTE_ARCH_ARM64
75 if (!(alg & CRC32_ARM64))
76 RTE_LOG(WARNING, HASH,
77 "Unsupported CRC32 algorithm requested using CRC32_ARM64\n");
78 if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
79 crc32_alg = CRC32_ARM64;
80 #endif
81
82 if (crc32_alg == CRC32_SW)
83 RTE_LOG(WARNING, HASH,
84 "Unsupported CRC32 algorithm requested using CRC32_SW\n");
85 }
86
87 /* Setting the best available algorithm */
RTE_INIT(rte_hash_crc_init_alg)88 RTE_INIT(rte_hash_crc_init_alg)
89 {
90 #if defined(RTE_ARCH_X86)
91 rte_hash_crc_set_alg(CRC32_SSE42_x64);
92 #elif defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
93 rte_hash_crc_set_alg(CRC32_ARM64);
94 #else
95 rte_hash_crc_set_alg(CRC32_SW);
96 #endif
97 }
98
99 #ifdef __DOXYGEN__
100
101 /**
102 * Use single CRC32 instruction to perform a hash on a byte value.
103 *
104 * @param data
105 * Data to perform hash on.
106 * @param init_val
107 * Value to initialise hash generator.
108 * @return
109 * 32bit calculated hash value.
110 */
111 static inline uint32_t
112 rte_hash_crc_1byte(uint8_t data, uint32_t init_val);
113
114 /**
115 * Use single CRC32 instruction to perform a hash on a 2 bytes value.
116 *
117 * @param data
118 * Data to perform hash on.
119 * @param init_val
120 * Value to initialise hash generator.
121 * @return
122 * 32bit calculated hash value.
123 */
124 static inline uint32_t
125 rte_hash_crc_2byte(uint16_t data, uint32_t init_val);
126
127 /**
128 * Use single CRC32 instruction to perform a hash on a 4 bytes value.
129 *
130 * @param data
131 * Data to perform hash on.
132 * @param init_val
133 * Value to initialise hash generator.
134 * @return
135 * 32bit calculated hash value.
136 */
137 static inline uint32_t
138 rte_hash_crc_4byte(uint32_t data, uint32_t init_val);
139
140 /**
141 * Use single CRC32 instruction to perform a hash on a 8 bytes value.
142 *
143 * @param data
144 * Data to perform hash on.
145 * @param init_val
146 * Value to initialise hash generator.
147 * @return
148 * 32bit calculated hash value.
149 */
150 static inline uint32_t
151 rte_hash_crc_8byte(uint64_t data, uint32_t init_val);
152
153 #endif /* __DOXYGEN__ */
154
155 /**
156 * Calculate CRC32 hash on user-supplied byte array.
157 *
158 * @param data
159 * Data to perform hash on.
160 * @param data_len
161 * How many bytes to use to calculate hash value.
162 * @param init_val
163 * Value to initialise hash generator.
164 * @return
165 * 32bit calculated hash value.
166 */
167 static inline uint32_t
rte_hash_crc(const void * data,uint32_t data_len,uint32_t init_val)168 rte_hash_crc(const void *data, uint32_t data_len, uint32_t init_val)
169 {
170 unsigned i;
171 uintptr_t pd = (uintptr_t) data;
172
173 for (i = 0; i < data_len / 8; i++) {
174 init_val = rte_hash_crc_8byte(*(const uint64_t *)pd, init_val);
175 pd += 8;
176 }
177
178 if (data_len & 0x4) {
179 init_val = rte_hash_crc_4byte(*(const uint32_t *)pd, init_val);
180 pd += 4;
181 }
182
183 if (data_len & 0x2) {
184 init_val = rte_hash_crc_2byte(*(const uint16_t *)pd, init_val);
185 pd += 2;
186 }
187
188 if (data_len & 0x1)
189 init_val = rte_hash_crc_1byte(*(const uint8_t *)pd, init_val);
190
191 return init_val;
192 }
193
194 #ifdef __cplusplus
195 }
196 #endif
197
198 #endif /* _RTE_HASH_CRC_H_ */
199