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(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(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(ctx->crc, data, 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(ctx->crc, data, 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(ctx->crc, 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(~ctx->crc, 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(crc32_mips_le_hw(crc, data, len), 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(~crc32c_mips_le_hw(crc, data, len), 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(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(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(desc->tfm); 258 259 return __chksum_finup(mctx->key, data, 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(desc->tfm); 266 267 return __chksumc_finup(mctx->key, data, 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(&crc32_alg); 325 326 if (err) 327 return err; 328 329 err = crypto_register_shash(&crc32c_alg); 330 331 if (err) { 332 crypto_unregister_shash(&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(&crc32_alg); 342 crypto_unregister_shash(&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