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 <asm/unaligned.h> 13 #include <linux/scatterlist.h> 14 15 /* This is a totally arbitrary value */ 16 #define SS_TIMEOUT 100 17 18 int sun4i_hash_crainit(struct crypto_tfm *tfm) 19 { 20 struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm); 21 struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg); 22 struct sun4i_ss_alg_template *algt; 23 int err; 24 25 memset(op, 0, sizeof(struct sun4i_tfm_ctx)); 26 27 algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash); 28 op->ss = algt->ss; 29 30 err = pm_runtime_get_sync(op->ss->dev); 31 if (err < 0) 32 return err; 33 34 crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm), 35 sizeof(struct sun4i_req_ctx)); 36 return 0; 37 } 38 39 void sun4i_hash_craexit(struct crypto_tfm *tfm) 40 { 41 struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm); 42 43 pm_runtime_put(op->ss->dev); 44 } 45 46 /* sun4i_hash_init: initialize request context */ 47 int sun4i_hash_init(struct ahash_request *areq) 48 { 49 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 50 struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); 51 struct ahash_alg *alg = __crypto_ahash_alg(tfm->base.__crt_alg); 52 struct sun4i_ss_alg_template *algt; 53 54 memset(op, 0, sizeof(struct sun4i_req_ctx)); 55 56 algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash); 57 op->mode = algt->mode; 58 59 return 0; 60 } 61 62 int sun4i_hash_export_md5(struct ahash_request *areq, void *out) 63 { 64 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 65 struct md5_state *octx = out; 66 int i; 67 68 octx->byte_count = op->byte_count + op->len; 69 70 memcpy(octx->block, op->buf, op->len); 71 72 if (op->byte_count) { 73 for (i = 0; i < 4; i++) 74 octx->hash[i] = op->hash[i]; 75 } else { 76 octx->hash[0] = SHA1_H0; 77 octx->hash[1] = SHA1_H1; 78 octx->hash[2] = SHA1_H2; 79 octx->hash[3] = SHA1_H3; 80 } 81 82 return 0; 83 } 84 85 int sun4i_hash_import_md5(struct ahash_request *areq, const void *in) 86 { 87 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 88 const struct md5_state *ictx = in; 89 int i; 90 91 sun4i_hash_init(areq); 92 93 op->byte_count = ictx->byte_count & ~0x3F; 94 op->len = ictx->byte_count & 0x3F; 95 96 memcpy(op->buf, ictx->block, op->len); 97 98 for (i = 0; i < 4; i++) 99 op->hash[i] = ictx->hash[i]; 100 101 return 0; 102 } 103 104 int sun4i_hash_export_sha1(struct ahash_request *areq, void *out) 105 { 106 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 107 struct sha1_state *octx = out; 108 int i; 109 110 octx->count = op->byte_count + op->len; 111 112 memcpy(octx->buffer, op->buf, op->len); 113 114 if (op->byte_count) { 115 for (i = 0; i < 5; i++) 116 octx->state[i] = op->hash[i]; 117 } else { 118 octx->state[0] = SHA1_H0; 119 octx->state[1] = SHA1_H1; 120 octx->state[2] = SHA1_H2; 121 octx->state[3] = SHA1_H3; 122 octx->state[4] = SHA1_H4; 123 } 124 125 return 0; 126 } 127 128 int sun4i_hash_import_sha1(struct ahash_request *areq, const void *in) 129 { 130 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 131 const struct sha1_state *ictx = in; 132 int i; 133 134 sun4i_hash_init(areq); 135 136 op->byte_count = ictx->count & ~0x3F; 137 op->len = ictx->count & 0x3F; 138 139 memcpy(op->buf, ictx->buffer, op->len); 140 141 for (i = 0; i < 5; i++) 142 op->hash[i] = ictx->state[i]; 143 144 return 0; 145 } 146 147 #define SS_HASH_UPDATE 1 148 #define SS_HASH_FINAL 2 149 150 /* 151 * sun4i_hash_update: update hash engine 152 * 153 * Could be used for both SHA1 and MD5 154 * Write data by step of 32bits and put then in the SS. 155 * 156 * Since we cannot leave partial data and hash state in the engine, 157 * we need to get the hash state at the end of this function. 158 * We can get the hash state every 64 bytes 159 * 160 * So the first work is to get the number of bytes to write to SS modulo 64 161 * The extra bytes will go to a temporary buffer op->buf storing op->len bytes 162 * 163 * So at the begin of update() 164 * if op->len + areq->nbytes < 64 165 * => all data will be written to wait buffer (op->buf) and end=0 166 * if not, write all data from op->buf to the device and position end to 167 * complete to 64bytes 168 * 169 * example 1: 170 * update1 60o => op->len=60 171 * update2 60o => need one more word to have 64 bytes 172 * end=4 173 * so write all data from op->buf and one word of SGs 174 * write remaining data in op->buf 175 * final state op->len=56 176 */ 177 static int sun4i_hash(struct ahash_request *areq) 178 { 179 /* 180 * i is the total bytes read from SGs, to be compared to areq->nbytes 181 * i is important because we cannot rely on SG length since the sum of 182 * SG->length could be greater than areq->nbytes 183 * 184 * end is the position when we need to stop writing to the device, 185 * to be compared to i 186 * 187 * in_i: advancement in the current SG 188 */ 189 unsigned int i = 0, end, fill, min_fill, nwait, nbw = 0, j = 0, todo; 190 unsigned int in_i = 0; 191 u32 spaces, rx_cnt = SS_RX_DEFAULT, bf[32] = {0}, v, ivmode = 0; 192 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 193 struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq); 194 struct sun4i_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm); 195 struct sun4i_ss_ctx *ss = tfmctx->ss; 196 struct scatterlist *in_sg = areq->src; 197 struct sg_mapping_iter mi; 198 int in_r, err = 0; 199 size_t copied = 0; 200 u32 wb = 0; 201 202 dev_dbg(ss->dev, "%s %s bc=%llu len=%u mode=%x wl=%u h0=%0x", 203 __func__, crypto_tfm_alg_name(areq->base.tfm), 204 op->byte_count, areq->nbytes, op->mode, 205 op->len, op->hash[0]); 206 207 if (unlikely(!areq->nbytes) && !(op->flags & SS_HASH_FINAL)) 208 return 0; 209 210 /* protect against overflow */ 211 if (unlikely(areq->nbytes > UINT_MAX - op->len)) { 212 dev_err(ss->dev, "Cannot process too large request\n"); 213 return -EINVAL; 214 } 215 216 if (op->len + areq->nbytes < 64 && !(op->flags & SS_HASH_FINAL)) { 217 /* linearize data to op->buf */ 218 copied = sg_pcopy_to_buffer(areq->src, sg_nents(areq->src), 219 op->buf + op->len, areq->nbytes, 0); 220 op->len += copied; 221 return 0; 222 } 223 224 spin_lock_bh(&ss->slock); 225 226 /* 227 * if some data have been processed before, 228 * we need to restore the partial hash state 229 */ 230 if (op->byte_count) { 231 ivmode = SS_IV_ARBITRARY; 232 for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) 233 writel(op->hash[i], ss->base + SS_IV0 + i * 4); 234 } 235 /* Enable the device */ 236 writel(op->mode | SS_ENABLED | ivmode, ss->base + SS_CTL); 237 238 if (!(op->flags & SS_HASH_UPDATE)) 239 goto hash_final; 240 241 /* start of handling data */ 242 if (!(op->flags & SS_HASH_FINAL)) { 243 end = ((areq->nbytes + op->len) / 64) * 64 - op->len; 244 245 if (end > areq->nbytes || areq->nbytes - end > 63) { 246 dev_err(ss->dev, "ERROR: Bound error %u %u\n", 247 end, areq->nbytes); 248 err = -EINVAL; 249 goto release_ss; 250 } 251 } else { 252 /* Since we have the flag final, we can go up to modulo 4 */ 253 if (areq->nbytes < 4) 254 end = 0; 255 else 256 end = ((areq->nbytes + op->len) / 4) * 4 - op->len; 257 } 258 259 /* TODO if SGlen % 4 and !op->len then DMA */ 260 i = 1; 261 while (in_sg && i == 1) { 262 if (in_sg->length % 4) 263 i = 0; 264 in_sg = sg_next(in_sg); 265 } 266 if (i == 1 && !op->len && areq->nbytes) 267 dev_dbg(ss->dev, "We can DMA\n"); 268 269 i = 0; 270 sg_miter_start(&mi, areq->src, sg_nents(areq->src), 271 SG_MITER_FROM_SG | SG_MITER_ATOMIC); 272 sg_miter_next(&mi); 273 in_i = 0; 274 275 do { 276 /* 277 * we need to linearize in two case: 278 * - the buffer is already used 279 * - the SG does not have enough byte remaining ( < 4) 280 */ 281 if (op->len || (mi.length - in_i) < 4) { 282 /* 283 * if we have entered here we have two reason to stop 284 * - the buffer is full 285 * - reach the end 286 */ 287 while (op->len < 64 && i < end) { 288 /* how many bytes we can read from current SG */ 289 in_r = min(end - i, 64 - op->len); 290 in_r = min_t(size_t, mi.length - in_i, in_r); 291 memcpy(op->buf + op->len, mi.addr + in_i, in_r); 292 op->len += in_r; 293 i += in_r; 294 in_i += in_r; 295 if (in_i == mi.length) { 296 sg_miter_next(&mi); 297 in_i = 0; 298 } 299 } 300 if (op->len > 3 && !(op->len % 4)) { 301 /* write buf to the device */ 302 writesl(ss->base + SS_RXFIFO, op->buf, 303 op->len / 4); 304 op->byte_count += op->len; 305 op->len = 0; 306 } 307 } 308 if (mi.length - in_i > 3 && i < end) { 309 /* how many bytes we can read from current SG */ 310 in_r = min_t(size_t, mi.length - in_i, areq->nbytes - i); 311 in_r = min_t(size_t, ((mi.length - in_i) / 4) * 4, in_r); 312 /* how many bytes we can write in the device*/ 313 todo = min3((u32)(end - i) / 4, rx_cnt, (u32)in_r / 4); 314 writesl(ss->base + SS_RXFIFO, mi.addr + in_i, todo); 315 op->byte_count += todo * 4; 316 i += todo * 4; 317 in_i += todo * 4; 318 rx_cnt -= todo; 319 if (!rx_cnt) { 320 spaces = readl(ss->base + SS_FCSR); 321 rx_cnt = SS_RXFIFO_SPACES(spaces); 322 } 323 if (in_i == mi.length) { 324 sg_miter_next(&mi); 325 in_i = 0; 326 } 327 } 328 } while (i < end); 329 330 /* 331 * Now we have written to the device all that we can, 332 * store the remaining bytes in op->buf 333 */ 334 if ((areq->nbytes - i) < 64) { 335 while (i < areq->nbytes && in_i < mi.length && op->len < 64) { 336 /* how many bytes we can read from current SG */ 337 in_r = min(areq->nbytes - i, 64 - op->len); 338 in_r = min_t(size_t, mi.length - in_i, in_r); 339 memcpy(op->buf + op->len, mi.addr + in_i, in_r); 340 op->len += in_r; 341 i += in_r; 342 in_i += in_r; 343 if (in_i == mi.length) { 344 sg_miter_next(&mi); 345 in_i = 0; 346 } 347 } 348 } 349 350 sg_miter_stop(&mi); 351 352 /* 353 * End of data process 354 * Now if we have the flag final go to finalize part 355 * If not, store the partial hash 356 */ 357 if (op->flags & SS_HASH_FINAL) 358 goto hash_final; 359 360 writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); 361 i = 0; 362 do { 363 v = readl(ss->base + SS_CTL); 364 i++; 365 } while (i < SS_TIMEOUT && (v & SS_DATA_END)); 366 if (unlikely(i >= SS_TIMEOUT)) { 367 dev_err_ratelimited(ss->dev, 368 "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", 369 i, SS_TIMEOUT, v, areq->nbytes); 370 err = -EIO; 371 goto release_ss; 372 } 373 374 /* 375 * The datasheet isn't very clear about when to retrieve the digest. The 376 * bit SS_DATA_END is cleared when the engine has processed the data and 377 * when the digest is computed *but* it doesn't mean the digest is 378 * available in the digest registers. Hence the delay to be sure we can 379 * read it. 380 */ 381 ndelay(1); 382 383 for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) 384 op->hash[i] = readl(ss->base + SS_MD0 + i * 4); 385 386 goto release_ss; 387 388 /* 389 * hash_final: finalize hashing operation 390 * 391 * If we have some remaining bytes, we write them. 392 * Then ask the SS for finalizing the hashing operation 393 * 394 * I do not check RX FIFO size in this function since the size is 32 395 * after each enabling and this function neither write more than 32 words. 396 * If we come from the update part, we cannot have more than 397 * 3 remaining bytes to write and SS is fast enough to not care about it. 398 */ 399 400 hash_final: 401 402 /* write the remaining words of the wait buffer */ 403 if (op->len) { 404 nwait = op->len / 4; 405 if (nwait) { 406 writesl(ss->base + SS_RXFIFO, op->buf, nwait); 407 op->byte_count += 4 * nwait; 408 } 409 410 nbw = op->len - 4 * nwait; 411 if (nbw) { 412 wb = le32_to_cpup((__le32 *)(op->buf + nwait * 4)); 413 wb &= GENMASK((nbw * 8) - 1, 0); 414 415 op->byte_count += nbw; 416 } 417 } 418 419 /* write the remaining bytes of the nbw buffer */ 420 wb |= ((1 << 7) << (nbw * 8)); 421 ((__le32 *)bf)[j++] = cpu_to_le32(wb); 422 423 /* 424 * number of space to pad to obtain 64o minus 8(size) minus 4 (final 1) 425 * I take the operations from other MD5/SHA1 implementations 426 */ 427 428 /* last block size */ 429 fill = 64 - (op->byte_count % 64); 430 min_fill = 2 * sizeof(u32) + (nbw ? 0 : sizeof(u32)); 431 432 /* if we can't fill all data, jump to the next 64 block */ 433 if (fill < min_fill) 434 fill += 64; 435 436 j += (fill - min_fill) / sizeof(u32); 437 438 /* write the length of data */ 439 if (op->mode == SS_OP_SHA1) { 440 __be64 *bits = (__be64 *)&bf[j]; 441 *bits = cpu_to_be64(op->byte_count << 3); 442 j += 2; 443 } else { 444 __le64 *bits = (__le64 *)&bf[j]; 445 *bits = cpu_to_le64(op->byte_count << 3); 446 j += 2; 447 } 448 writesl(ss->base + SS_RXFIFO, bf, j); 449 450 /* Tell the SS to stop the hashing */ 451 writel(op->mode | SS_ENABLED | SS_DATA_END, ss->base + SS_CTL); 452 453 /* 454 * Wait for SS to finish the hash. 455 * The timeout could happen only in case of bad overclocking 456 * or driver bug. 457 */ 458 i = 0; 459 do { 460 v = readl(ss->base + SS_CTL); 461 i++; 462 } while (i < SS_TIMEOUT && (v & SS_DATA_END)); 463 if (unlikely(i >= SS_TIMEOUT)) { 464 dev_err_ratelimited(ss->dev, 465 "ERROR: hash end timeout %d>%d ctl=%x len=%u\n", 466 i, SS_TIMEOUT, v, areq->nbytes); 467 err = -EIO; 468 goto release_ss; 469 } 470 471 /* 472 * The datasheet isn't very clear about when to retrieve the digest. The 473 * bit SS_DATA_END is cleared when the engine has processed the data and 474 * when the digest is computed *but* it doesn't mean the digest is 475 * available in the digest registers. Hence the delay to be sure we can 476 * read it. 477 */ 478 ndelay(1); 479 480 /* Get the hash from the device */ 481 if (op->mode == SS_OP_SHA1) { 482 for (i = 0; i < 5; i++) { 483 v = readl(ss->base + SS_MD0 + i * 4); 484 if (ss->variant->sha1_in_be) 485 put_unaligned_le32(v, areq->result + i * 4); 486 else 487 put_unaligned_be32(v, areq->result + i * 4); 488 } 489 } else { 490 for (i = 0; i < 4; i++) { 491 v = readl(ss->base + SS_MD0 + i * 4); 492 put_unaligned_le32(v, areq->result + i * 4); 493 } 494 } 495 496 release_ss: 497 writel(0, ss->base + SS_CTL); 498 spin_unlock_bh(&ss->slock); 499 return err; 500 } 501 502 int sun4i_hash_final(struct ahash_request *areq) 503 { 504 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 505 506 op->flags = SS_HASH_FINAL; 507 return sun4i_hash(areq); 508 } 509 510 int sun4i_hash_update(struct ahash_request *areq) 511 { 512 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 513 514 op->flags = SS_HASH_UPDATE; 515 return sun4i_hash(areq); 516 } 517 518 /* sun4i_hash_finup: finalize hashing operation after an update */ 519 int sun4i_hash_finup(struct ahash_request *areq) 520 { 521 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 522 523 op->flags = SS_HASH_UPDATE | SS_HASH_FINAL; 524 return sun4i_hash(areq); 525 } 526 527 /* combo of init/update/final functions */ 528 int sun4i_hash_digest(struct ahash_request *areq) 529 { 530 int err; 531 struct sun4i_req_ctx *op = ahash_request_ctx(areq); 532 533 err = sun4i_hash_init(areq); 534 if (err) 535 return err; 536 537 op->flags = SS_HASH_UPDATE | SS_HASH_FINAL; 538 return sun4i_hash(areq); 539 } 540