1 /* Copyright (C) 2004-2006, Advanced Micro Devices, Inc. 2 * 3 * This program is free software; you can redistribute it and/or modify 4 * it under the terms of the GNU General Public License as published by 5 * the Free Software Foundation; either version 2 of the License, or 6 * (at your option) any later version. 7 */ 8 9 #include <linux/module.h> 10 #include <linux/kernel.h> 11 #include <linux/pci.h> 12 #include <linux/pci_ids.h> 13 #include <linux/crypto.h> 14 #include <linux/spinlock.h> 15 #include <crypto/algapi.h> 16 #include <crypto/aes.h> 17 18 #include <linux/io.h> 19 #include <linux/delay.h> 20 21 #include "geode-aes.h" 22 23 /* Static structures */ 24 25 static void __iomem *_iobase; 26 static spinlock_t lock; 27 28 /* Write a 128 bit field (either a writable key or IV) */ 29 static inline void 30 _writefield(u32 offset, void *value) 31 { 32 int i; 33 34 for (i = 0; i < 4; i++) 35 iowrite32(((u32 *) value)[i], _iobase + offset + (i * 4)); 36 } 37 38 /* Read a 128 bit field (either a writable key or IV) */ 39 static inline void 40 _readfield(u32 offset, void *value) 41 { 42 int i; 43 44 for (i = 0; i < 4; i++) 45 ((u32 *) value)[i] = ioread32(_iobase + offset + (i * 4)); 46 } 47 48 static int 49 do_crypt(void *src, void *dst, int len, u32 flags) 50 { 51 u32 status; 52 u32 counter = AES_OP_TIMEOUT; 53 54 iowrite32(virt_to_phys(src), _iobase + AES_SOURCEA_REG); 55 iowrite32(virt_to_phys(dst), _iobase + AES_DSTA_REG); 56 iowrite32(len, _iobase + AES_LENA_REG); 57 58 /* Start the operation */ 59 iowrite32(AES_CTRL_START | flags, _iobase + AES_CTRLA_REG); 60 61 do { 62 status = ioread32(_iobase + AES_INTR_REG); 63 cpu_relax(); 64 } while (!(status & AES_INTRA_PENDING) && --counter); 65 66 /* Clear the event */ 67 iowrite32((status & 0xFF) | AES_INTRA_PENDING, _iobase + AES_INTR_REG); 68 return counter ? 0 : 1; 69 } 70 71 static unsigned int 72 geode_aes_crypt(struct geode_aes_op *op) 73 { 74 u32 flags = 0; 75 unsigned long iflags; 76 int ret; 77 78 if (op->len == 0) 79 return 0; 80 81 /* If the source and destination is the same, then 82 * we need to turn on the coherent flags, otherwise 83 * we don't need to worry 84 */ 85 86 flags |= (AES_CTRL_DCA | AES_CTRL_SCA); 87 88 if (op->dir == AES_DIR_ENCRYPT) 89 flags |= AES_CTRL_ENCRYPT; 90 91 /* Start the critical section */ 92 93 spin_lock_irqsave(&lock, iflags); 94 95 if (op->mode == AES_MODE_CBC) { 96 flags |= AES_CTRL_CBC; 97 _writefield(AES_WRITEIV0_REG, op->iv); 98 } 99 100 if (!(op->flags & AES_FLAGS_HIDDENKEY)) { 101 flags |= AES_CTRL_WRKEY; 102 _writefield(AES_WRITEKEY0_REG, op->key); 103 } 104 105 ret = do_crypt(op->src, op->dst, op->len, flags); 106 BUG_ON(ret); 107 108 if (op->mode == AES_MODE_CBC) 109 _readfield(AES_WRITEIV0_REG, op->iv); 110 111 spin_unlock_irqrestore(&lock, iflags); 112 113 return op->len; 114 } 115 116 /* CRYPTO-API Functions */ 117 118 static int geode_setkey_cip(struct crypto_tfm *tfm, const u8 *key, 119 unsigned int len) 120 { 121 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 122 unsigned int ret; 123 124 op->keylen = len; 125 126 if (len == AES_KEYSIZE_128) { 127 memcpy(op->key, key, len); 128 return 0; 129 } 130 131 if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256) { 132 /* not supported at all */ 133 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 134 return -EINVAL; 135 } 136 137 /* 138 * The requested key size is not supported by HW, do a fallback 139 */ 140 op->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 141 op->fallback.cip->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK); 142 143 ret = crypto_cipher_setkey(op->fallback.cip, key, len); 144 if (ret) { 145 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 146 tfm->crt_flags |= (op->fallback.cip->base.crt_flags & CRYPTO_TFM_RES_MASK); 147 } 148 return ret; 149 } 150 151 static int geode_setkey_blk(struct crypto_tfm *tfm, const u8 *key, 152 unsigned int len) 153 { 154 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 155 unsigned int ret; 156 157 op->keylen = len; 158 159 if (len == AES_KEYSIZE_128) { 160 memcpy(op->key, key, len); 161 return 0; 162 } 163 164 if (len != AES_KEYSIZE_192 && len != AES_KEYSIZE_256) { 165 /* not supported at all */ 166 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; 167 return -EINVAL; 168 } 169 170 /* 171 * The requested key size is not supported by HW, do a fallback 172 */ 173 op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; 174 op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK); 175 176 ret = crypto_blkcipher_setkey(op->fallback.blk, key, len); 177 if (ret) { 178 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; 179 tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK); 180 } 181 return ret; 182 } 183 184 static int fallback_blk_dec(struct blkcipher_desc *desc, 185 struct scatterlist *dst, struct scatterlist *src, 186 unsigned int nbytes) 187 { 188 unsigned int ret; 189 struct crypto_blkcipher *tfm; 190 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 191 192 tfm = desc->tfm; 193 desc->tfm = op->fallback.blk; 194 195 ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); 196 197 desc->tfm = tfm; 198 return ret; 199 } 200 static int fallback_blk_enc(struct blkcipher_desc *desc, 201 struct scatterlist *dst, struct scatterlist *src, 202 unsigned int nbytes) 203 { 204 unsigned int ret; 205 struct crypto_blkcipher *tfm; 206 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 207 208 tfm = desc->tfm; 209 desc->tfm = op->fallback.blk; 210 211 ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); 212 213 desc->tfm = tfm; 214 return ret; 215 } 216 217 static void 218 geode_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 219 { 220 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 221 222 if (unlikely(op->keylen != AES_KEYSIZE_128)) { 223 crypto_cipher_encrypt_one(op->fallback.cip, out, in); 224 return; 225 } 226 227 op->src = (void *) in; 228 op->dst = (void *) out; 229 op->mode = AES_MODE_ECB; 230 op->flags = 0; 231 op->len = AES_BLOCK_SIZE; 232 op->dir = AES_DIR_ENCRYPT; 233 234 geode_aes_crypt(op); 235 } 236 237 238 static void 239 geode_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 240 { 241 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 242 243 if (unlikely(op->keylen != AES_KEYSIZE_128)) { 244 crypto_cipher_decrypt_one(op->fallback.cip, out, in); 245 return; 246 } 247 248 op->src = (void *) in; 249 op->dst = (void *) out; 250 op->mode = AES_MODE_ECB; 251 op->flags = 0; 252 op->len = AES_BLOCK_SIZE; 253 op->dir = AES_DIR_DECRYPT; 254 255 geode_aes_crypt(op); 256 } 257 258 static int fallback_init_cip(struct crypto_tfm *tfm) 259 { 260 const char *name = crypto_tfm_alg_name(tfm); 261 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 262 263 op->fallback.cip = crypto_alloc_cipher(name, 0, 264 CRYPTO_ALG_NEED_FALLBACK); 265 266 if (IS_ERR(op->fallback.cip)) { 267 printk(KERN_ERR "Error allocating fallback algo %s\n", name); 268 return PTR_ERR(op->fallback.cip); 269 } 270 271 return 0; 272 } 273 274 static void fallback_exit_cip(struct crypto_tfm *tfm) 275 { 276 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 277 278 crypto_free_cipher(op->fallback.cip); 279 op->fallback.cip = NULL; 280 } 281 282 static struct crypto_alg geode_alg = { 283 .cra_name = "aes", 284 .cra_driver_name = "geode-aes", 285 .cra_priority = 300, 286 .cra_alignmask = 15, 287 .cra_flags = CRYPTO_ALG_TYPE_CIPHER | 288 CRYPTO_ALG_NEED_FALLBACK, 289 .cra_init = fallback_init_cip, 290 .cra_exit = fallback_exit_cip, 291 .cra_blocksize = AES_BLOCK_SIZE, 292 .cra_ctxsize = sizeof(struct geode_aes_op), 293 .cra_module = THIS_MODULE, 294 .cra_u = { 295 .cipher = { 296 .cia_min_keysize = AES_MIN_KEY_SIZE, 297 .cia_max_keysize = AES_MAX_KEY_SIZE, 298 .cia_setkey = geode_setkey_cip, 299 .cia_encrypt = geode_encrypt, 300 .cia_decrypt = geode_decrypt 301 } 302 } 303 }; 304 305 static int 306 geode_cbc_decrypt(struct blkcipher_desc *desc, 307 struct scatterlist *dst, struct scatterlist *src, 308 unsigned int nbytes) 309 { 310 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 311 struct blkcipher_walk walk; 312 int err, ret; 313 314 if (unlikely(op->keylen != AES_KEYSIZE_128)) 315 return fallback_blk_dec(desc, dst, src, nbytes); 316 317 blkcipher_walk_init(&walk, dst, src, nbytes); 318 err = blkcipher_walk_virt(desc, &walk); 319 op->iv = walk.iv; 320 321 while ((nbytes = walk.nbytes)) { 322 op->src = walk.src.virt.addr, 323 op->dst = walk.dst.virt.addr; 324 op->mode = AES_MODE_CBC; 325 op->len = nbytes - (nbytes % AES_BLOCK_SIZE); 326 op->dir = AES_DIR_DECRYPT; 327 328 ret = geode_aes_crypt(op); 329 330 nbytes -= ret; 331 err = blkcipher_walk_done(desc, &walk, nbytes); 332 } 333 334 return err; 335 } 336 337 static int 338 geode_cbc_encrypt(struct blkcipher_desc *desc, 339 struct scatterlist *dst, struct scatterlist *src, 340 unsigned int nbytes) 341 { 342 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 343 struct blkcipher_walk walk; 344 int err, ret; 345 346 if (unlikely(op->keylen != AES_KEYSIZE_128)) 347 return fallback_blk_enc(desc, dst, src, nbytes); 348 349 blkcipher_walk_init(&walk, dst, src, nbytes); 350 err = blkcipher_walk_virt(desc, &walk); 351 op->iv = walk.iv; 352 353 while ((nbytes = walk.nbytes)) { 354 op->src = walk.src.virt.addr, 355 op->dst = walk.dst.virt.addr; 356 op->mode = AES_MODE_CBC; 357 op->len = nbytes - (nbytes % AES_BLOCK_SIZE); 358 op->dir = AES_DIR_ENCRYPT; 359 360 ret = geode_aes_crypt(op); 361 nbytes -= ret; 362 err = blkcipher_walk_done(desc, &walk, nbytes); 363 } 364 365 return err; 366 } 367 368 static int fallback_init_blk(struct crypto_tfm *tfm) 369 { 370 const char *name = crypto_tfm_alg_name(tfm); 371 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 372 373 op->fallback.blk = crypto_alloc_blkcipher(name, 0, 374 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); 375 376 if (IS_ERR(op->fallback.blk)) { 377 printk(KERN_ERR "Error allocating fallback algo %s\n", name); 378 return PTR_ERR(op->fallback.blk); 379 } 380 381 return 0; 382 } 383 384 static void fallback_exit_blk(struct crypto_tfm *tfm) 385 { 386 struct geode_aes_op *op = crypto_tfm_ctx(tfm); 387 388 crypto_free_blkcipher(op->fallback.blk); 389 op->fallback.blk = NULL; 390 } 391 392 static struct crypto_alg geode_cbc_alg = { 393 .cra_name = "cbc(aes)", 394 .cra_driver_name = "cbc-aes-geode", 395 .cra_priority = 400, 396 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | 397 CRYPTO_ALG_KERN_DRIVER_ONLY | 398 CRYPTO_ALG_NEED_FALLBACK, 399 .cra_init = fallback_init_blk, 400 .cra_exit = fallback_exit_blk, 401 .cra_blocksize = AES_BLOCK_SIZE, 402 .cra_ctxsize = sizeof(struct geode_aes_op), 403 .cra_alignmask = 15, 404 .cra_type = &crypto_blkcipher_type, 405 .cra_module = THIS_MODULE, 406 .cra_u = { 407 .blkcipher = { 408 .min_keysize = AES_MIN_KEY_SIZE, 409 .max_keysize = AES_MAX_KEY_SIZE, 410 .setkey = geode_setkey_blk, 411 .encrypt = geode_cbc_encrypt, 412 .decrypt = geode_cbc_decrypt, 413 .ivsize = AES_BLOCK_SIZE, 414 } 415 } 416 }; 417 418 static int 419 geode_ecb_decrypt(struct blkcipher_desc *desc, 420 struct scatterlist *dst, struct scatterlist *src, 421 unsigned int nbytes) 422 { 423 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 424 struct blkcipher_walk walk; 425 int err, ret; 426 427 if (unlikely(op->keylen != AES_KEYSIZE_128)) 428 return fallback_blk_dec(desc, dst, src, nbytes); 429 430 blkcipher_walk_init(&walk, dst, src, nbytes); 431 err = blkcipher_walk_virt(desc, &walk); 432 433 while ((nbytes = walk.nbytes)) { 434 op->src = walk.src.virt.addr, 435 op->dst = walk.dst.virt.addr; 436 op->mode = AES_MODE_ECB; 437 op->len = nbytes - (nbytes % AES_BLOCK_SIZE); 438 op->dir = AES_DIR_DECRYPT; 439 440 ret = geode_aes_crypt(op); 441 nbytes -= ret; 442 err = blkcipher_walk_done(desc, &walk, nbytes); 443 } 444 445 return err; 446 } 447 448 static int 449 geode_ecb_encrypt(struct blkcipher_desc *desc, 450 struct scatterlist *dst, struct scatterlist *src, 451 unsigned int nbytes) 452 { 453 struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); 454 struct blkcipher_walk walk; 455 int err, ret; 456 457 if (unlikely(op->keylen != AES_KEYSIZE_128)) 458 return fallback_blk_enc(desc, dst, src, nbytes); 459 460 blkcipher_walk_init(&walk, dst, src, nbytes); 461 err = blkcipher_walk_virt(desc, &walk); 462 463 while ((nbytes = walk.nbytes)) { 464 op->src = walk.src.virt.addr, 465 op->dst = walk.dst.virt.addr; 466 op->mode = AES_MODE_ECB; 467 op->len = nbytes - (nbytes % AES_BLOCK_SIZE); 468 op->dir = AES_DIR_ENCRYPT; 469 470 ret = geode_aes_crypt(op); 471 nbytes -= ret; 472 ret = blkcipher_walk_done(desc, &walk, nbytes); 473 } 474 475 return err; 476 } 477 478 static struct crypto_alg geode_ecb_alg = { 479 .cra_name = "ecb(aes)", 480 .cra_driver_name = "ecb-aes-geode", 481 .cra_priority = 400, 482 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | 483 CRYPTO_ALG_KERN_DRIVER_ONLY | 484 CRYPTO_ALG_NEED_FALLBACK, 485 .cra_init = fallback_init_blk, 486 .cra_exit = fallback_exit_blk, 487 .cra_blocksize = AES_BLOCK_SIZE, 488 .cra_ctxsize = sizeof(struct geode_aes_op), 489 .cra_alignmask = 15, 490 .cra_type = &crypto_blkcipher_type, 491 .cra_module = THIS_MODULE, 492 .cra_u = { 493 .blkcipher = { 494 .min_keysize = AES_MIN_KEY_SIZE, 495 .max_keysize = AES_MAX_KEY_SIZE, 496 .setkey = geode_setkey_blk, 497 .encrypt = geode_ecb_encrypt, 498 .decrypt = geode_ecb_decrypt, 499 } 500 } 501 }; 502 503 static void geode_aes_remove(struct pci_dev *dev) 504 { 505 crypto_unregister_alg(&geode_alg); 506 crypto_unregister_alg(&geode_ecb_alg); 507 crypto_unregister_alg(&geode_cbc_alg); 508 509 pci_iounmap(dev, _iobase); 510 _iobase = NULL; 511 512 pci_release_regions(dev); 513 pci_disable_device(dev); 514 } 515 516 517 static int geode_aes_probe(struct pci_dev *dev, const struct pci_device_id *id) 518 { 519 int ret; 520 521 ret = pci_enable_device(dev); 522 if (ret) 523 return ret; 524 525 ret = pci_request_regions(dev, "geode-aes"); 526 if (ret) 527 goto eenable; 528 529 _iobase = pci_iomap(dev, 0, 0); 530 531 if (_iobase == NULL) { 532 ret = -ENOMEM; 533 goto erequest; 534 } 535 536 spin_lock_init(&lock); 537 538 /* Clear any pending activity */ 539 iowrite32(AES_INTR_PENDING | AES_INTR_MASK, _iobase + AES_INTR_REG); 540 541 ret = crypto_register_alg(&geode_alg); 542 if (ret) 543 goto eiomap; 544 545 ret = crypto_register_alg(&geode_ecb_alg); 546 if (ret) 547 goto ealg; 548 549 ret = crypto_register_alg(&geode_cbc_alg); 550 if (ret) 551 goto eecb; 552 553 dev_notice(&dev->dev, "GEODE AES engine enabled.\n"); 554 return 0; 555 556 eecb: 557 crypto_unregister_alg(&geode_ecb_alg); 558 559 ealg: 560 crypto_unregister_alg(&geode_alg); 561 562 eiomap: 563 pci_iounmap(dev, _iobase); 564 565 erequest: 566 pci_release_regions(dev); 567 568 eenable: 569 pci_disable_device(dev); 570 571 dev_err(&dev->dev, "GEODE AES initialization failed.\n"); 572 return ret; 573 } 574 575 static struct pci_device_id geode_aes_tbl[] = { 576 { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_LX_AES), }, 577 { 0, } 578 }; 579 580 MODULE_DEVICE_TABLE(pci, geode_aes_tbl); 581 582 static struct pci_driver geode_aes_driver = { 583 .name = "Geode LX AES", 584 .id_table = geode_aes_tbl, 585 .probe = geode_aes_probe, 586 .remove = geode_aes_remove, 587 }; 588 589 module_pci_driver(geode_aes_driver); 590 591 MODULE_AUTHOR("Advanced Micro Devices, Inc."); 592 MODULE_DESCRIPTION("Geode LX Hardware AES driver"); 593 MODULE_LICENSE("GPL"); 594