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