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_MACRO_CRC32(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 _ASM_MACRO_CRC32(crc32b, 0, 0); 41 _ASM_MACRO_CRC32(crc32h, 1, 0); 42 _ASM_MACRO_CRC32(crc32w, 2, 0); 43 _ASM_MACRO_CRC32(crc32d, 3, 0); 44 _ASM_MACRO_CRC32(crc32cb, 0, 1); 45 _ASM_MACRO_CRC32(crc32ch, 1, 1); 46 _ASM_MACRO_CRC32(crc32cw, 2, 1); 47 _ASM_MACRO_CRC32(crc32cd, 3, 1); 48 #define _ASM_SET_CRC "" 49 #else /* !TOOLCHAIN_SUPPORTS_CRC */ 50 #define _ASM_SET_CRC ".set\tcrc\n\t" 51 #endif 52 53 #define _CRC32(crc, value, size, type) \ 54 do { \ 55 __asm__ __volatile__( \ 56 ".set push\n\t" \ 57 _ASM_SET_CRC \ 58 #type #size " %0, %1, %0\n\t" \ 59 ".set pop" \ 60 : "+r" (crc) \ 61 : "r" (value)); \ 62 } while (0) 63 64 #define CRC32(crc, value, size) \ 65 _CRC32(crc, value, size, crc32) 66 67 #define CRC32C(crc, value, size) \ 68 _CRC32(crc, value, size, crc32c) 69 70 static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) 71 { 72 u32 crc = crc_; 73 74 #ifdef CONFIG_64BIT 75 while (len >= sizeof(u64)) { 76 u64 value = get_unaligned_le64(p); 77 78 CRC32(crc, value, d); 79 p += sizeof(u64); 80 len -= sizeof(u64); 81 } 82 83 if (len & sizeof(u32)) { 84 #else /* !CONFIG_64BIT */ 85 while (len >= sizeof(u32)) { 86 #endif 87 u32 value = get_unaligned_le32(p); 88 89 CRC32(crc, value, w); 90 p += sizeof(u32); 91 len -= sizeof(u32); 92 } 93 94 if (len & sizeof(u16)) { 95 u16 value = get_unaligned_le16(p); 96 97 CRC32(crc, value, h); 98 p += sizeof(u16); 99 } 100 101 if (len & sizeof(u8)) { 102 u8 value = *p++; 103 104 CRC32(crc, value, b); 105 } 106 107 return crc; 108 } 109 110 static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) 111 { 112 u32 crc = crc_; 113 114 #ifdef CONFIG_64BIT 115 while (len >= sizeof(u64)) { 116 u64 value = get_unaligned_le64(p); 117 118 CRC32C(crc, value, d); 119 p += sizeof(u64); 120 len -= sizeof(u64); 121 } 122 123 if (len & sizeof(u32)) { 124 #else /* !CONFIG_64BIT */ 125 while (len >= sizeof(u32)) { 126 #endif 127 u32 value = get_unaligned_le32(p); 128 129 CRC32C(crc, value, w); 130 p += sizeof(u32); 131 len -= sizeof(u32); 132 } 133 134 if (len & sizeof(u16)) { 135 u16 value = get_unaligned_le16(p); 136 137 CRC32C(crc, value, h); 138 p += sizeof(u16); 139 } 140 141 if (len & sizeof(u8)) { 142 u8 value = *p++; 143 144 CRC32C(crc, value, b); 145 } 146 return crc; 147 } 148 149 #define CHKSUM_BLOCK_SIZE 1 150 #define CHKSUM_DIGEST_SIZE 4 151 152 struct chksum_ctx { 153 u32 key; 154 }; 155 156 struct chksum_desc_ctx { 157 u32 crc; 158 }; 159 160 static int chksum_init(struct shash_desc *desc) 161 { 162 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 163 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 164 165 ctx->crc = mctx->key; 166 167 return 0; 168 } 169 170 /* 171 * Setting the seed allows arbitrary accumulators and flexible XOR policy 172 * If your algorithm starts with ~0, then XOR with ~0 before you set 173 * the seed. 174 */ 175 static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, 176 unsigned int keylen) 177 { 178 struct chksum_ctx *mctx = crypto_shash_ctx(tfm); 179 180 if (keylen != sizeof(mctx->key)) 181 return -EINVAL; 182 mctx->key = get_unaligned_le32(key); 183 return 0; 184 } 185 186 static int chksum_update(struct shash_desc *desc, const u8 *data, 187 unsigned int length) 188 { 189 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 190 191 ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); 192 return 0; 193 } 194 195 static int chksumc_update(struct shash_desc *desc, const u8 *data, 196 unsigned int length) 197 { 198 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 199 200 ctx->crc = crc32c_mips_le_hw(ctx->crc, data, length); 201 return 0; 202 } 203 204 static int chksum_final(struct shash_desc *desc, u8 *out) 205 { 206 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 207 208 put_unaligned_le32(ctx->crc, out); 209 return 0; 210 } 211 212 static int chksumc_final(struct shash_desc *desc, u8 *out) 213 { 214 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 215 216 put_unaligned_le32(~ctx->crc, out); 217 return 0; 218 } 219 220 static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) 221 { 222 put_unaligned_le32(crc32_mips_le_hw(crc, data, len), out); 223 return 0; 224 } 225 226 static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) 227 { 228 put_unaligned_le32(~crc32c_mips_le_hw(crc, data, len), out); 229 return 0; 230 } 231 232 static int chksum_finup(struct shash_desc *desc, const u8 *data, 233 unsigned int len, u8 *out) 234 { 235 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 236 237 return __chksum_finup(ctx->crc, data, len, out); 238 } 239 240 static int chksumc_finup(struct shash_desc *desc, const u8 *data, 241 unsigned int len, u8 *out) 242 { 243 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 244 245 return __chksumc_finup(ctx->crc, data, len, out); 246 } 247 248 static int chksum_digest(struct shash_desc *desc, const u8 *data, 249 unsigned int length, u8 *out) 250 { 251 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 252 253 return __chksum_finup(mctx->key, data, length, out); 254 } 255 256 static int chksumc_digest(struct shash_desc *desc, const u8 *data, 257 unsigned int length, u8 *out) 258 { 259 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 260 261 return __chksumc_finup(mctx->key, data, length, out); 262 } 263 264 static int chksum_cra_init(struct crypto_tfm *tfm) 265 { 266 struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); 267 268 mctx->key = ~0; 269 return 0; 270 } 271 272 static struct shash_alg crc32_alg = { 273 .digestsize = CHKSUM_DIGEST_SIZE, 274 .setkey = chksum_setkey, 275 .init = chksum_init, 276 .update = chksum_update, 277 .final = chksum_final, 278 .finup = chksum_finup, 279 .digest = chksum_digest, 280 .descsize = sizeof(struct chksum_desc_ctx), 281 .base = { 282 .cra_name = "crc32", 283 .cra_driver_name = "crc32-mips-hw", 284 .cra_priority = 300, 285 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, 286 .cra_blocksize = CHKSUM_BLOCK_SIZE, 287 .cra_alignmask = 0, 288 .cra_ctxsize = sizeof(struct chksum_ctx), 289 .cra_module = THIS_MODULE, 290 .cra_init = chksum_cra_init, 291 } 292 }; 293 294 static struct shash_alg crc32c_alg = { 295 .digestsize = CHKSUM_DIGEST_SIZE, 296 .setkey = chksum_setkey, 297 .init = chksum_init, 298 .update = chksumc_update, 299 .final = chksumc_final, 300 .finup = chksumc_finup, 301 .digest = chksumc_digest, 302 .descsize = sizeof(struct chksum_desc_ctx), 303 .base = { 304 .cra_name = "crc32c", 305 .cra_driver_name = "crc32c-mips-hw", 306 .cra_priority = 300, 307 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, 308 .cra_blocksize = CHKSUM_BLOCK_SIZE, 309 .cra_alignmask = 0, 310 .cra_ctxsize = sizeof(struct chksum_ctx), 311 .cra_module = THIS_MODULE, 312 .cra_init = chksum_cra_init, 313 } 314 }; 315 316 static int __init crc32_mod_init(void) 317 { 318 int err; 319 320 err = crypto_register_shash(&crc32_alg); 321 322 if (err) 323 return err; 324 325 err = crypto_register_shash(&crc32c_alg); 326 327 if (err) { 328 crypto_unregister_shash(&crc32_alg); 329 return err; 330 } 331 332 return 0; 333 } 334 335 static void __exit crc32_mod_exit(void) 336 { 337 crypto_unregister_shash(&crc32_alg); 338 crypto_unregister_shash(&crc32c_alg); 339 } 340 341 MODULE_AUTHOR("Marcin Nowakowski <marcin.nowakowski@mips.com"); 342 MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions"); 343 MODULE_LICENSE("GPL v2"); 344 345 module_cpu_feature_match(MIPS_CRC32, crc32_mod_init); 346 module_exit(crc32_mod_exit); 347