1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * crc32-mips.c - CRC32 and CRC32C using optional MIPSr6 instructions |
4 | * |
5 | * Module based on arm64/crypto/crc32-arm.c |
6 | * |
7 | * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org> |
8 | * Copyright (C) 2018 MIPS Tech, LLC |
9 | */ |
10 | |
11 | #include <linux/cpufeature.h> |
12 | #include <linux/init.h> |
13 | #include <linux/kernel.h> |
14 | #include <linux/module.h> |
15 | #include <linux/string.h> |
16 | #include <asm/mipsregs.h> |
17 | #include <asm/unaligned.h> |
18 | |
19 | #include <crypto/internal/hash.h> |
20 | |
21 | enum crc_op_size { |
22 | b, h, w, d, |
23 | }; |
24 | |
25 | enum crc_type { |
26 | crc32, |
27 | crc32c, |
28 | }; |
29 | |
30 | #ifndef TOOLCHAIN_SUPPORTS_CRC |
31 | #define _ASM_SET_CRC(OP, SZ, TYPE) \ |
32 | _ASM_MACRO_3R(OP, rt, rs, rt2, \ |
33 | ".ifnc \\rt, \\rt2\n\t" \ |
34 | ".error \"invalid operands \\\"" #OP " \\rt,\\rs,\\rt2\\\"\"\n\t" \ |
35 | ".endif\n\t" \ |
36 | _ASM_INSN_IF_MIPS(0x7c00000f | (__rt << 16) | (__rs << 21) | \ |
37 | ((SZ) << 6) | ((TYPE) << 8)) \ |
38 | _ASM_INSN32_IF_MM(0x00000030 | (__rs << 16) | (__rt << 21) | \ |
39 | ((SZ) << 14) | ((TYPE) << 3))) |
40 | #define _ASM_UNSET_CRC(op, SZ, TYPE) ".purgem " #op "\n\t" |
41 | #else /* !TOOLCHAIN_SUPPORTS_CRC */ |
42 | #define _ASM_SET_CRC(op, SZ, TYPE) ".set\tcrc\n\t" |
43 | #define _ASM_UNSET_CRC(op, SZ, TYPE) |
44 | #endif |
45 | |
46 | #define __CRC32(crc, value, op, SZ, TYPE) \ |
47 | do { \ |
48 | __asm__ __volatile__( \ |
49 | ".set push\n\t" \ |
50 | _ASM_SET_CRC(op, SZ, TYPE) \ |
51 | #op " %0, %1, %0\n\t" \ |
52 | _ASM_UNSET_CRC(op, SZ, TYPE) \ |
53 | ".set pop" \ |
54 | : "+r" (crc) \ |
55 | : "r" (value)); \ |
56 | } while (0) |
57 | |
58 | #define _CRC32_crc32b(crc, value) __CRC32(crc, value, crc32b, 0, 0) |
59 | #define _CRC32_crc32h(crc, value) __CRC32(crc, value, crc32h, 1, 0) |
60 | #define _CRC32_crc32w(crc, value) __CRC32(crc, value, crc32w, 2, 0) |
61 | #define _CRC32_crc32d(crc, value) __CRC32(crc, value, crc32d, 3, 0) |
62 | #define _CRC32_crc32cb(crc, value) __CRC32(crc, value, crc32cb, 0, 1) |
63 | #define _CRC32_crc32ch(crc, value) __CRC32(crc, value, crc32ch, 1, 1) |
64 | #define _CRC32_crc32cw(crc, value) __CRC32(crc, value, crc32cw, 2, 1) |
65 | #define _CRC32_crc32cd(crc, value) __CRC32(crc, value, crc32cd, 3, 1) |
66 | |
67 | #define _CRC32(crc, value, size, op) \ |
68 | _CRC32_##op##size(crc, value) |
69 | |
70 | #define CRC32(crc, value, size) \ |
71 | _CRC32(crc, value, size, crc32) |
72 | |
73 | #define CRC32C(crc, value, size) \ |
74 | _CRC32(crc, value, size, crc32c) |
75 | |
76 | static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) |
77 | { |
78 | u32 crc = crc_; |
79 | |
80 | #ifdef CONFIG_64BIT |
81 | while (len >= sizeof(u64)) { |
82 | u64 value = get_unaligned_le64(p); |
83 | |
84 | CRC32(crc, value, d); |
85 | p += sizeof(u64); |
86 | len -= sizeof(u64); |
87 | } |
88 | |
89 | if (len & sizeof(u32)) { |
90 | #else /* !CONFIG_64BIT */ |
91 | while (len >= sizeof(u32)) { |
92 | #endif |
93 | u32 value = get_unaligned_le32(p); |
94 | |
95 | CRC32(crc, value, w); |
96 | p += sizeof(u32); |
97 | len -= sizeof(u32); |
98 | } |
99 | |
100 | if (len & sizeof(u16)) { |
101 | u16 value = get_unaligned_le16(p); |
102 | |
103 | CRC32(crc, value, h); |
104 | p += sizeof(u16); |
105 | } |
106 | |
107 | if (len & sizeof(u8)) { |
108 | u8 value = *p++; |
109 | |
110 | CRC32(crc, value, b); |
111 | } |
112 | |
113 | return crc; |
114 | } |
115 | |
116 | static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) |
117 | { |
118 | u32 crc = crc_; |
119 | |
120 | #ifdef CONFIG_64BIT |
121 | while (len >= sizeof(u64)) { |
122 | u64 value = get_unaligned_le64(p); |
123 | |
124 | CRC32C(crc, value, d); |
125 | p += sizeof(u64); |
126 | len -= sizeof(u64); |
127 | } |
128 | |
129 | if (len & sizeof(u32)) { |
130 | #else /* !CONFIG_64BIT */ |
131 | while (len >= sizeof(u32)) { |
132 | #endif |
133 | u32 value = get_unaligned_le32(p); |
134 | |
135 | CRC32C(crc, value, w); |
136 | p += sizeof(u32); |
137 | len -= sizeof(u32); |
138 | } |
139 | |
140 | if (len & sizeof(u16)) { |
141 | u16 value = get_unaligned_le16(p); |
142 | |
143 | CRC32C(crc, value, h); |
144 | p += sizeof(u16); |
145 | } |
146 | |
147 | if (len & sizeof(u8)) { |
148 | u8 value = *p++; |
149 | |
150 | CRC32C(crc, value, b); |
151 | } |
152 | return crc; |
153 | } |
154 | |
155 | #define CHKSUM_BLOCK_SIZE 1 |
156 | #define CHKSUM_DIGEST_SIZE 4 |
157 | |
158 | struct chksum_ctx { |
159 | u32 key; |
160 | }; |
161 | |
162 | struct chksum_desc_ctx { |
163 | u32 crc; |
164 | }; |
165 | |
166 | static int chksum_init(struct shash_desc *desc) |
167 | { |
168 | struct chksum_ctx *mctx = crypto_shash_ctx(tfm: desc->tfm); |
169 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
170 | |
171 | ctx->crc = mctx->key; |
172 | |
173 | return 0; |
174 | } |
175 | |
176 | /* |
177 | * Setting the seed allows arbitrary accumulators and flexible XOR policy |
178 | * If your algorithm starts with ~0, then XOR with ~0 before you set |
179 | * the seed. |
180 | */ |
181 | static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, |
182 | unsigned int keylen) |
183 | { |
184 | struct chksum_ctx *mctx = crypto_shash_ctx(tfm); |
185 | |
186 | if (keylen != sizeof(mctx->key)) |
187 | return -EINVAL; |
188 | mctx->key = get_unaligned_le32(p: key); |
189 | return 0; |
190 | } |
191 | |
192 | static int chksum_update(struct shash_desc *desc, const u8 *data, |
193 | unsigned int length) |
194 | { |
195 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
196 | |
197 | ctx->crc = crc32_mips_le_hw(crc_: ctx->crc, p: data, len: length); |
198 | return 0; |
199 | } |
200 | |
201 | static int chksumc_update(struct shash_desc *desc, const u8 *data, |
202 | unsigned int length) |
203 | { |
204 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
205 | |
206 | ctx->crc = crc32c_mips_le_hw(crc_: ctx->crc, p: data, len: length); |
207 | return 0; |
208 | } |
209 | |
210 | static int chksum_final(struct shash_desc *desc, u8 *out) |
211 | { |
212 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
213 | |
214 | put_unaligned_le32(val: ctx->crc, p: out); |
215 | return 0; |
216 | } |
217 | |
218 | static int chksumc_final(struct shash_desc *desc, u8 *out) |
219 | { |
220 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
221 | |
222 | put_unaligned_le32(val: ~ctx->crc, p: out); |
223 | return 0; |
224 | } |
225 | |
226 | static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) |
227 | { |
228 | put_unaligned_le32(val: crc32_mips_le_hw(crc_: crc, p: data, len), p: out); |
229 | return 0; |
230 | } |
231 | |
232 | static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) |
233 | { |
234 | put_unaligned_le32(val: ~crc32c_mips_le_hw(crc_: crc, p: data, len), p: out); |
235 | return 0; |
236 | } |
237 | |
238 | static int chksum_finup(struct shash_desc *desc, const u8 *data, |
239 | unsigned int len, u8 *out) |
240 | { |
241 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
242 | |
243 | return __chksum_finup(crc: ctx->crc, data, len, out); |
244 | } |
245 | |
246 | static int chksumc_finup(struct shash_desc *desc, const u8 *data, |
247 | unsigned int len, u8 *out) |
248 | { |
249 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
250 | |
251 | return __chksumc_finup(crc: ctx->crc, data, len, out); |
252 | } |
253 | |
254 | static int chksum_digest(struct shash_desc *desc, const u8 *data, |
255 | unsigned int length, u8 *out) |
256 | { |
257 | struct chksum_ctx *mctx = crypto_shash_ctx(tfm: desc->tfm); |
258 | |
259 | return __chksum_finup(crc: mctx->key, data, len: length, out); |
260 | } |
261 | |
262 | static int chksumc_digest(struct shash_desc *desc, const u8 *data, |
263 | unsigned int length, u8 *out) |
264 | { |
265 | struct chksum_ctx *mctx = crypto_shash_ctx(tfm: desc->tfm); |
266 | |
267 | return __chksumc_finup(crc: mctx->key, data, len: length, out); |
268 | } |
269 | |
270 | static int chksum_cra_init(struct crypto_tfm *tfm) |
271 | { |
272 | struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); |
273 | |
274 | mctx->key = ~0; |
275 | return 0; |
276 | } |
277 | |
278 | static struct shash_alg crc32_alg = { |
279 | .digestsize = CHKSUM_DIGEST_SIZE, |
280 | .setkey = chksum_setkey, |
281 | .init = chksum_init, |
282 | .update = chksum_update, |
283 | .final = chksum_final, |
284 | .finup = chksum_finup, |
285 | .digest = chksum_digest, |
286 | .descsize = sizeof(struct chksum_desc_ctx), |
287 | .base = { |
288 | .cra_name = "crc32" , |
289 | .cra_driver_name = "crc32-mips-hw" , |
290 | .cra_priority = 300, |
291 | .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, |
292 | .cra_blocksize = CHKSUM_BLOCK_SIZE, |
293 | .cra_ctxsize = sizeof(struct chksum_ctx), |
294 | .cra_module = THIS_MODULE, |
295 | .cra_init = chksum_cra_init, |
296 | } |
297 | }; |
298 | |
299 | static struct shash_alg crc32c_alg = { |
300 | .digestsize = CHKSUM_DIGEST_SIZE, |
301 | .setkey = chksum_setkey, |
302 | .init = chksum_init, |
303 | .update = chksumc_update, |
304 | .final = chksumc_final, |
305 | .finup = chksumc_finup, |
306 | .digest = chksumc_digest, |
307 | .descsize = sizeof(struct chksum_desc_ctx), |
308 | .base = { |
309 | .cra_name = "crc32c" , |
310 | .cra_driver_name = "crc32c-mips-hw" , |
311 | .cra_priority = 300, |
312 | .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, |
313 | .cra_blocksize = CHKSUM_BLOCK_SIZE, |
314 | .cra_ctxsize = sizeof(struct chksum_ctx), |
315 | .cra_module = THIS_MODULE, |
316 | .cra_init = chksum_cra_init, |
317 | } |
318 | }; |
319 | |
320 | static int __init crc32_mod_init(void) |
321 | { |
322 | int err; |
323 | |
324 | err = crypto_register_shash(alg: &crc32_alg); |
325 | |
326 | if (err) |
327 | return err; |
328 | |
329 | err = crypto_register_shash(alg: &crc32c_alg); |
330 | |
331 | if (err) { |
332 | crypto_unregister_shash(alg: &crc32_alg); |
333 | return err; |
334 | } |
335 | |
336 | return 0; |
337 | } |
338 | |
339 | static void __exit crc32_mod_exit(void) |
340 | { |
341 | crypto_unregister_shash(alg: &crc32_alg); |
342 | crypto_unregister_shash(alg: &crc32c_alg); |
343 | } |
344 | |
345 | MODULE_AUTHOR("Marcin Nowakowski <marcin.nowakowski@mips.com" ); |
346 | MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions" ); |
347 | MODULE_LICENSE("GPL v2" ); |
348 | |
349 | module_cpu_feature_match(MIPS_CRC32, crc32_mod_init); |
350 | module_exit(crc32_mod_exit); |
351 | |