1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * sun4i-ss-hash.c - hardware cryptographic accelerator for Allwinner A20 SoC 4 * 5 * Copyright (C) 2013-2015 Corentin LABBE <clabbe.montjoie@gmail.com> 6 * 7 * This file add support for MD5 and SHA1. 8 * 9 * You could find the datasheet in Documentation/arm/sunxi.rst 10 */ 11 #include "sun4i-ss.h" 12 #include <linux/scatterlist.h> 13 14 /* This is a totally arbitrary value */ 15 #define SS_TIMEOUT 100 16 17 int sun4i_hash_crainit(struct crypto_tfm *tfm) 18 { 19 struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm); 20 struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg); 21 struct sun4i_ss_alg_template *algt; 22 int err; 23 24 memset(op, 0, sizeof(struct sun4i_tfm_ctx)); 25 26 algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash); 27 op->ss = algt->ss; 28 29 err = pm_runtime_get_sync(op->ss->dev); 30 if (err < 0) 31 return err; 32 33 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm), 34 sizeof(struct sun4i_req_ctx)); 35 return 0; 36 } 37 38 void sun4i_hash_craexit(struct crypto_tfm *tfm) 39 { 40 struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm); 41 42 pm_runtime_put(op->ss->dev); 43 } 44 45 /* sun4i_hash_init: initialize request context */ 46 int sun4i_hash_init(struct ahash_request *areq) 47 { 48 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 49 struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); 50 struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg); 51 struct sun4i_ss_alg_template *algt; 52 53 memset(op, 0, sizeof(struct sun4i_req_ctx)); 54 55 algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash); 56 op->mode = algt->mode; 57 58 return 0; 59 } 60 61 int sun4i_hash_export_md5(struct ahash_request *areq, void *out) 62 { 63 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 64 struct md5_state *octx = out; 65 int i; 66 67 octx->byte_count = op->byte_count + op->len; 68 69 memcpy(octx->block, op->buf, op->len); 70 71 if (op->byte_count) { 72 for (i = 0; i < 4; i++) 73 octx->hash[i] = op->hash[i]; 74 } else { 75 octx->hash[0] = SHA1_H0; 76 octx->hash[1] = SHA1_H1; 77 octx->hash[2] = SHA1_H2; 78 octx->hash[3] = SHA1_H3; 79 } 80 81 return 0; 82 } 83 84 int sun4i_hash_import_md5(struct ahash_request *areq, const void *in) 85 { 86 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 87 const struct md5_state *ictx = in; 88 int i; 89 90 sun4i_hash_init(areq); 91 92 op->byte_count = ictx->byte_count & ~0x3F; 93 op->len = ictx->byte_count & 0x3F; 94 95 memcpy(op->buf, ictx->block, op->len); 96 97 for (i = 0; i < 4; i++) 98 op->hash[i] = ictx->hash[i]; 99 100 return 0; 101 } 102 103 int sun4i_hash_export_sha1(struct ahash_request *areq, void *out) 104 { 105 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 106 struct sha1_state *octx = out; 107 int i; 108 109 octx->count = op->byte_count + op->len; 110 111 memcpy(octx->buffer, op->buf, op->len); 112 113 if (op->byte_count) { 114 for (i = 0; i < 5; i++) 115 octx->state[i] = op->hash[i]; 116 } else { 117 octx->state[0] = SHA1_H0; 118 octx->state[1] = SHA1_H1; 119 octx->state[2] = SHA1_H2; 120 octx->state[3] = SHA1_H3; 121 octx->state[4] = SHA1_H4; 122 } 123 124 return 0; 125 } 126 127 int sun4i_hash_import_sha1(struct ahash_request *areq, const void *in) 128 { 129 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 130 const struct sha1_state *ictx = in; 131 int i; 132 133 sun4i_hash_init(areq); 134 135 op->byte_count = ictx->count & ~0x3F; 136 op->len = ictx->count & 0x3F; 137 138 memcpy(op->buf, ictx->buffer, op->len); 139 140 for (i = 0; i < 5; i++) 141 op->hash[i] = ictx->state[i]; 142 143 return 0; 144 } 145 146 #define SS_HASH_UPDATE 1 147 #define SS_HASH_FINAL 2 148 149 /* 150 * sun4i_hash_update: update hash engine 151 * 152 * Could be used for both SHA1 and MD5 153 * Write data by step of 32bits and put then in the SS. 154 * 155 * Since we cannot leave partial data and hash state in the engine, 156 * we need to get the hash state at the end of this function. 157 * We can get the hash state every 64 bytes 158 * 159 * So the first work is to get the number of bytes to write to SS modulo 64 160 * The extra bytes will go to a temporary buffer op->buf storing op->len bytes 161 * 162 * So at the begin of update() 163 * if op->len + areq->nbytes < 64 164 * => all data will be written to wait buffer (op->buf) and end=0 165 * if not, write all data from op->buf to the device and position end to 166 * complete to 64bytes 167 * 168 * example 1: 169 * update1 60o => op->len=60 170 * update2 60o => need one more word to have 64 bytes 171 * end=4 172 * so write all data from op->buf and one word of SGs 173 * write remaining data in op->buf 174 * final state op->len=56 175 */ 176 static int sun4i_hash(struct ahash_request *areq) 177 { 178 /* 179 * i is the total bytes read from SGs, to be compared to areq->nbytes 180 * i is important because we cannot rely on SG length since the sum of 181 * SG->length could be greater than areq->nbytes 182 * 183 * end is the position when we need to stop writing to the device, 184 * to be compared to i 185 * 186 * in_i: advancement in the current SG 187 */ 188 unsigned int i = 0, end, fill, min_fill, nwait, nbw = 0, j = 0, todo; 189 unsigned int in_i = 0; 190 u32 spaces, rx_cnt = SS_RX_DEFAULT, bf[32] = {0}, v, ivmode = 0; 191 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 192 struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); 193 struct sun4i_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm); 194 struct sun4i_ss_ctx *ss = tfmctx->ss; 195 struct scatterlist *in_sg = areq->src; 196 struct sg_mapping_iter mi; 197 int in_r, err = 0; 198 size_t copied = 0; 199 __le32 wb = 0; 200 201 dev_dbg(ss->dev, "%s %s bc=%llu len=%u mode=%x wl=%u h0=%0x", 202 __func__, crypto_tfm_alg_name(areq->base.tfm), 203 op->byte_count, areq->nbytes, op->mode, 204 op->len, op->hash[0]); 205 206 if (unlikely(!areq->nbytes) && !(op->flags & SS_HASH_FINAL)) 207 return 0; 208 209 /* protect against overflow */ 210 if (unlikely(areq->nbytes > UINT_MAX - op->len)) { 211 dev_err(ss->dev, "Cannot process too large request\n"); 212 return -EINVAL; 213 } 214 215 if (op->len + areq->nbytes < 64 && !(op->flags & SS_HASH_FINAL)) { 216 /* linearize data to op->buf */ 217 copied = sg_pcopy_to_buffer(areq->src, sg_nents(areq->src), 218 op->buf + op->len, areq->nbytes, 0); 219 op->len += copied; 220 return 0; 221 } 222 223 spin_lock_bh(&ss->slock); 224 225 /* 226 * if some data have been processed before, 227 * we need to restore the partial hash state 228 */ 229 if (op->byte_count) { 230 ivmode = SS_IV_ARBITRARY; 231 for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) 232 writel(op->hash[i], ss->base + SS_IV0 + i * 4); 233 } 234 /* Enable the device */ 235 writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL); 236 237 if (!(op->flags & SS_HASH_UPDATE)) 238 goto hash_final; 239 240 /* start of handling data */ 241 if (!(op->flags & SS_HASH_FINAL)) { 242 end = ((areq->nbytes + op->len) / 64) * 64 - op->len; 243 244 if (end > areq->nbytes || areq->nbytes - end > 63) { 245 dev_err(ss->dev, "ERROR: Bound error %u %u\n", 246 end, areq->nbytes); 247 err = -EINVAL; 248 goto release_ss; 249 } 250 } else { 251 /* Since we have the flag final, we can go up to modulo 4 */ 252 if (areq->nbytes < 4) 253 end = 0; 254 else 255 end = ((areq->nbytes + op->len) / 4) * 4 - op->len; 256 } 257 258 /* TODO if SGlen % 4 and !op->len then DMA */ 259 i = 1; 260 while (in_sg && i == 1) { 261 if (in_sg->length % 4) 262 i = 0; 263 in_sg = sg_next(in_sg); 264 } 265 if (i == 1 && !op->len && areq->nbytes) 266 dev_dbg(ss->dev, "We can DMA\n"); 267 268 i = 0; 269 sg_miter_start(&mi, areq->src, sg_nents(areq->src), 270 SG_MITER_FROM_SG | SG_MITER_ATOMIC); 271 sg_miter_next(&mi); 272 in_i = 0; 273 274 do { 275 /* 276 * we need to linearize in two case: 277 * - the buffer is already used 278 * - the SG does not have enough byte remaining ( < 4) 279 */ 280 if (op->len || (mi.length - in_i) < 4) { 281 /* 282 * if we have entered here we have two reason to stop 283 * - the buffer is full 284 * - reach the end 285 */ 286 while (op->len < 64 && i < end) { 287 /* how many bytes we can read from current SG */ 288 in_r = min(end - i, 64 - op->len); 289 in_r = min_t(size_t, mi.length - in_i, in_r); 290 memcpy(op->buf + op->len, mi.addr + in_i, in_r); 291 op->len += in_r; 292 i += in_r; 293 in_i += in_r; 294 if (in_i == mi.length) { 295 sg_miter_next(&mi); 296 in_i = 0; 297 } 298 } 299 if (op->len > 3 && !(op->len % 4)) { 300 /* write buf to the device */ 301 writesl(ss->base + SS_RXFIFO, op->buf, 302 op->len / 4); 303 op->byte_count += op->len; 304 op->len = 0; 305 } 306 } 307 if (mi.length - in_i > 3 && i < end) { 308 /* how many bytes we can read from current SG */ 309 in_r = min_t(size_t, mi.length - in_i, areq->nbytes - i); 310 in_r = min_t(size_t, ((mi.length - in_i) / 4) * 4, in_r); 311 /* how many bytes we can write in the device*/ 312 todo = min3((u32)(end - i) / 4, rx_cnt, (u32)in_r / 4); 313 writesl(ss->base + SS_RXFIFO, mi.addr + in_i, todo); 314 op->byte_count += todo * 4; 315 i += todo * 4; 316 in_i += todo * 4; 317 rx_cnt -= todo; 318 if (!rx_cnt) { 319 spaces = readl(ss->base + SS_FCSR); 320 rx_cnt = SS_RXFIFO_SPACES(spaces); 321 } 322 if (in_i == mi.length) { 323 sg_miter_next(&mi); 324 in_i = 0; 325 } 326 } 327 } while (i < end); 328 329 /* 330 * Now we have written to the device all that we can, 331 * store the remaining bytes in op->buf 332 */ 333 if ((areq->nbytes - i) < 64) { 334 while (i < areq->nbytes && in_i < mi.length && op->len < 64) { 335 /* how many bytes we can read from current SG */ 336 in_r = min(areq->nbytes - i, 64 - op->len); 337 in_r = min_t(size_t, mi.length - in_i, in_r); 338 memcpy(op->buf + op->len, mi.addr + in_i, in_r); 339 op->len += in_r; 340 i += in_r; 341 in_i += in_r; 342 if (in_i == mi.length) { 343 sg_miter_next(&mi); 344 in_i = 0; 345 } 346 } 347 } 348 349 sg_miter_stop(&mi); 350 351 /* 352 * End of data process 353 * Now if we have the flag final go to finalize part 354 * If not, store the partial hash 355 */ 356 if (op->flags & SS_HASH_FINAL) 357 goto hash_final; 358 359 writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); 360 i = 0; 361 do { 362 v = readl(ss->base + SS_CTL); 363 i++; 364 } while (i < SS_TIMEOUT && (v & SS_DATA_END)); 365 if (unlikely(i >= SS_TIMEOUT)) { 366 dev_err_ratelimited(ss->dev, 367 "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", 368 i, SS_TIMEOUT, v, areq->nbytes); 369 err = -EIO; 370 goto release_ss; 371 } 372 373 /* 374 * The datasheet isn't very clear about when to retrieve the digest. The 375 * bit SS_DATA_END is cleared when the engine has processed the data and 376 * when the digest is computed *but* it doesn't mean the digest is 377 * available in the digest registers. Hence the delay to be sure we can 378 * read it. 379 */ 380 ndelay(1); 381 382 for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) 383 op->hash[i] = readl(ss->base + SS_MD0 + i * 4); 384 385 goto release_ss; 386 387 /* 388 * hash_final: finalize hashing operation 389 * 390 * If we have some remaining bytes, we write them. 391 * Then ask the SS for finalizing the hashing operation 392 * 393 * I do not check RX FIFO size in this function since the size is 32 394 * after each enabling and this function neither write more than 32 words. 395 * If we come from the update part, we cannot have more than 396 * 3 remaining bytes to write and SS is fast enough to not care about it. 397 */ 398 399 hash_final: 400 401 /* write the remaining words of the wait buffer */ 402 if (op->len) { 403 nwait = op->len / 4; 404 if (nwait) { 405 writesl(ss->base + SS_RXFIFO, op->buf, nwait); 406 op->byte_count += 4 * nwait; 407 } 408 409 nbw = op->len - 4 * nwait; 410 if (nbw) { 411 wb = cpu_to_le32(*(u32 *)(op->buf + nwait * 4)); 412 wb &= GENMASK((nbw * 8) - 1, 0); 413 414 op->byte_count += nbw; 415 } 416 } 417 418 /* write the remaining bytes of the nbw buffer */ 419 wb |= ((1 << 7) << (nbw * 8)); 420 bf[j++] = le32_to_cpu(wb); 421 422 /* 423 * number of space to pad to obtain 64o minus 8(size) minus 4 (final 1) 424 * I take the operations from other MD5/SHA1 implementations 425 */ 426 427 /* last block size */ 428 fill = 64 - (op->byte_count % 64); 429 min_fill = 2 * sizeof(u32) + (nbw ? 0 : sizeof(u32)); 430 431 /* if we can't fill all data, jump to the next 64 block */ 432 if (fill < min_fill) 433 fill += 64; 434 435 j += (fill - min_fill) / sizeof(u32); 436 437 /* write the length of data */ 438 if (op->mode == SS_OP_SHA1) { 439 __be64 *bits = (__be64 *)&bf[j]; 440 *bits = cpu_to_be64(op->byte_count << 3); 441 j += 2; 442 } else { 443 __le64 *bits = (__le64 *)&bf[j]; 444 *bits = cpu_to_le64(op->byte_count << 3); 445 j += 2; 446 } 447 writesl(ss->base + SS_RXFIFO, bf, j); 448 449 /* Tell the SS to stop the hashing */ 450 writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); 451 452 /* 453 * Wait for SS to finish the hash. 454 * The timeout could happen only in case of bad overclocking 455 * or driver bug. 456 */ 457 i = 0; 458 do { 459 v = readl(ss->base + SS_CTL); 460 i++; 461 } while (i < SS_TIMEOUT && (v & SS_DATA_END)); 462 if (unlikely(i >= SS_TIMEOUT)) { 463 dev_err_ratelimited(ss->dev, 464 "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", 465 i, SS_TIMEOUT, v, areq->nbytes); 466 err = -EIO; 467 goto release_ss; 468 } 469 470 /* 471 * The datasheet isn't very clear about when to retrieve the digest. The 472 * bit SS_DATA_END is cleared when the engine has processed the data and 473 * when the digest is computed *but* it doesn't mean the digest is 474 * available in the digest registers. Hence the delay to be sure we can 475 * read it. 476 */ 477 ndelay(1); 478 479 /* Get the hash from the device */ 480 if (op->mode == SS_OP_SHA1) { 481 for (i = 0; i < 5; i++) { 482 v = cpu_to_be32(readl(ss->base + SS_MD0 + i * 4)); 483 memcpy(areq->result + i * 4, &v, 4); 484 } 485 } else { 486 for (i = 0; i < 4; i++) { 487 v = cpu_to_le32(readl(ss->base + SS_MD0 + i * 4)); 488 memcpy(areq->result + i * 4, &v, 4); 489 } 490 } 491 492 release_ss: 493 writel(0, ss->base + SS_CTL); 494 spin_unlock_bh(&ss->slock); 495 return err; 496 } 497 498 int sun4i_hash_final(struct ahash_request *areq) 499 { 500 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 501 502 op->flags = SS_HASH_FINAL; 503 return sun4i_hash(areq); 504 } 505 506 int sun4i_hash_update(struct ahash_request *areq) 507 { 508 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 509 510 op->flags = SS_HASH_UPDATE; 511 return sun4i_hash(areq); 512 } 513 514 /* sun4i_hash_finup: finalize hashing operation after an update */ 515 int sun4i_hash_finup(struct ahash_request *areq) 516 { 517 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 518 519 op->flags = SS_HASH_UPDATE | SS_HASH_FINAL; 520 return sun4i_hash(areq); 521 } 522 523 /* combo of init/update/final functions */ 524 int sun4i_hash_digest(struct ahash_request *areq) 525 { 526 int err; 527 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 528 529 err = sun4i_hash_init(areq); 530 if (err) 531 return err; 532 533 op->flags = SS_HASH_UPDATE | SS_HASH_FINAL; 534 return sun4i_hash(areq); 535 } 536