drivers/crypto/bfin_crc.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Support Blackfin CRC HW acceleration.
   5  *
   6  * Copyright 2012 Analog Devices Inc.
   7  *
   8  * Licensed under the GPL-2.
   9  */
  10
  11 #include <linux/err.h>
  12 #include <linux/device.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/errno.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel.h>
  18 #include <linux/irq.h>
  19 #include <linux/io.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/scatterlist.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/delay.h>
  24 #include <linux/unaligned/access_ok.h>
  25 #include <linux/crypto.h>
  26 #include <linux/cryptohash.h>
  27 #include <crypto/scatterwalk.h>
  28 #include <crypto/algapi.h>
  29 #include <crypto/hash.h>
  30 #include <crypto/internal/hash.h>
  31
  32 #include <asm/blackfin.h>
  33 #include <asm/bfin_crc.h>
  34 #include <asm/dma.h>
  35 #include <asm/portmux.h>
  36
  37 #define CRC_CCRYPTO_QUEUE_LENGTH        5
  38
  39 #define DRIVER_NAME "bfin-hmac-crc"
  40 #define CHKSUM_DIGEST_SIZE      4
  41 #define CHKSUM_BLOCK_SIZE       1
  42
  43 #define CRC_MAX_DMA_DESC        100
  44
  45 #define CRC_CRYPTO_STATE_UPDATE         1
  46 #define CRC_CRYPTO_STATE_FINALUPDATE    2
  47 #define CRC_CRYPTO_STATE_FINISH         3
  48
  49 struct bfin_crypto_crc {
  50         struct list_head        list;
  51         struct device           *dev;
  52         spinlock_t              lock;
  53
  54         int                     irq;
  55         int                     dma_ch;
  56         u32                     poly;
  57         volatile struct crc_register *regs;
  58
  59         struct ahash_request    *req; /* current request in operation */
  60         struct dma_desc_array   *sg_cpu; /* virt addr of sg dma descriptors */
  61         dma_addr_t              sg_dma; /* phy addr of sg dma descriptors */
  62         u8                      *sg_mid_buf;
  63
  64         struct tasklet_struct   done_task;
  65         struct crypto_queue     queue; /* waiting requests */
  66
  67         u8                      busy:1; /* crc device in operation flag */
  68 };
  69
  70 static struct bfin_crypto_crc_list {
  71         struct list_head        dev_list;
  72         spinlock_t              lock;
  73 } crc_list;
  74
  75 struct bfin_crypto_crc_reqctx {
  76         struct bfin_crypto_crc  *crc;
  77
  78         unsigned int            total;  /* total request bytes */
  79         size_t                  sg_buflen; /* bytes for this update */
  80         unsigned int            sg_nents;
  81         struct scatterlist      *sg; /* sg list head for this update*/
  82         struct scatterlist      bufsl[2]; /* chained sg list */
  83
  84         size_t                  bufnext_len;
  85         size_t                  buflast_len;
  86         u8                      bufnext[CHKSUM_DIGEST_SIZE]; /* extra bytes for next udpate */
  87         u8                      buflast[CHKSUM_DIGEST_SIZE]; /* extra bytes from last udpate */
  88
  89         u8                      flag;
  90 };
  91
  92 struct bfin_crypto_crc_ctx {
  93         struct bfin_crypto_crc  *crc;
  94         u32                     key;
  95 };
  96
  97
  98 /*
  99  * derive number of elements in scatterlist
 100  */
 101 static int sg_count(struct scatterlist *sg_list)
 102 {
 103         struct scatterlist *sg = sg_list;
 104         int sg_nents = 1;
 105
 106         if (sg_list == NULL)
 107                 return 0;
 108
 109         while (!sg_is_last(sg)) {
 110                 sg_nents++;
 111                 sg = scatterwalk_sg_next(sg);
 112         }
 113
 114         return sg_nents;
 115 }
 116
 117 /*
 118  * get element in scatter list by given index
 119  */
 120 static struct scatterlist *sg_get(struct scatterlist *sg_list, unsigned int nents,
 121                                 unsigned int index)
 122 {
 123         struct scatterlist *sg = NULL;
 124         int i;
 125
 126         for_each_sg(sg_list, sg, nents, i)
 127                 if (i == index)
 128                         break;
 129
 130         return sg;
 131 }
 132
 133 static int bfin_crypto_crc_init_hw(struct bfin_crypto_crc *crc, u32 key)
 134 {
 135         crc->regs->datacntrld = 0;
 136         crc->regs->control = MODE_CALC_CRC << OPMODE_OFFSET;
 137         crc->regs->curresult = key;
 138
 139         /* setup CRC interrupts */
 140         crc->regs->status = CMPERRI | DCNTEXPI;
 141         crc->regs->intrenset = CMPERRI | DCNTEXPI;
 142         SSYNC();
 143
 144         return 0;
 145 }
 146
 147 static int bfin_crypto_crc_init(struct ahash_request *req)
 148 {
 149         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 150         struct bfin_crypto_crc_ctx *crc_ctx = crypto_ahash_ctx(tfm);
 151         struct bfin_crypto_crc_reqctx *ctx = ahash_request_ctx(req);
 152         struct bfin_crypto_crc *crc;
 153
 154         dev_dbg(ctx->crc->dev, "crc_init\n");
 155         spin_lock_bh(&crc_list.lock);
 156         list_for_each_entry(crc, &crc_list.dev_list, list) {
 157                 crc_ctx->crc = crc;
 158                 break;
 159         }
 160         spin_unlock_bh(&crc_list.lock);
 161
 162         if (sg_count(req->src) > CRC_MAX_DMA_DESC) {
 163                 dev_dbg(ctx->crc->dev, "init: requested sg list is too big > %d\n",
 164                         CRC_MAX_DMA_DESC);
 165                 return -EINVAL;
 166         }
 167
 168         ctx->crc = crc;
 169         ctx->bufnext_len = 0;
 170         ctx->buflast_len = 0;
 171         ctx->sg_buflen = 0;
 172         ctx->total = 0;
 173         ctx->flag = 0;
 174
 175         /* init crc results */
 176         put_unaligned_le32(crc_ctx->key, req->result);
 177
 178         dev_dbg(ctx->crc->dev, "init: digest size: %d\n",
 179                 crypto_ahash_digestsize(tfm));
 180
 181         return bfin_crypto_crc_init_hw(crc, crc_ctx->key);
 182 }
 183
 184 static void bfin_crypto_crc_config_dma(struct bfin_crypto_crc *crc)
 185 {
 186         struct scatterlist *sg;
 187         struct bfin_crypto_crc_reqctx *ctx = ahash_request_ctx(crc->req);
 188         int i = 0, j = 0;
 189         unsigned long dma_config;
 190         unsigned int dma_count;
 191         unsigned int dma_addr;
 192         unsigned int mid_dma_count = 0;
 193         int dma_mod;
 194
 195         dma_map_sg(crc->dev, ctx->sg, ctx->sg_nents, DMA_TO_DEVICE);
 196
 197         for_each_sg(ctx->sg, sg, ctx->sg_nents, j) {
 198                 dma_config = DMAFLOW_ARRAY | RESTART | NDSIZE_3 | DMAEN | PSIZE_32;
 199                 dma_addr = sg_dma_address(sg);
 200                 /* deduce extra bytes in last sg */
 201                 if (sg_is_last(sg))
 202                         dma_count = sg_dma_len(sg) - ctx->bufnext_len;
 203                 else
 204                         dma_count = sg_dma_len(sg);
 205
 206                 if (mid_dma_count) {
 207                         /* Append last middle dma buffer to 4 bytes with first
 208                            bytes in current sg buffer. Move addr of current
 209                            sg and deduce the length of current sg.
 210                          */
 211                         memcpy(crc->sg_mid_buf +((i-1) << 2) + mid_dma_count,
 212                                 (void *)dma_addr,
 213                                 CHKSUM_DIGEST_SIZE - mid_dma_count);
 214                         dma_addr += CHKSUM_DIGEST_SIZE - mid_dma_count;
 215                         dma_count -= CHKSUM_DIGEST_SIZE - mid_dma_count;
 216                 }
 217                 /* chop current sg dma len to multiple of 32 bits */
 218                 mid_dma_count = dma_count % 4;
 219                 dma_count &= ~0x3;
 220
 221                 if (dma_addr % 4 == 0) {
 222                         dma_config |= WDSIZE_32;
 223                         dma_count >>= 2;
 224                         dma_mod = 4;
 225                 } else if (dma_addr % 2 == 0) {
 226                         dma_config |= WDSIZE_16;
 227                         dma_count >>= 1;
 228                         dma_mod = 2;
 229                 } else {
 230                         dma_config |= WDSIZE_8;
 231                         dma_mod = 1;
 232                 }
 233
 234                 crc->sg_cpu[i].start_addr = dma_addr;
 235                 crc->sg_cpu[i].cfg = dma_config;
 236                 crc->sg_cpu[i].x_count = dma_count;
 237                 crc->sg_cpu[i].x_modify = dma_mod;
 238                 dev_dbg(crc->dev, "%d: crc_dma: start_addr:0x%lx, "
 239                         "cfg:0x%lx, x_count:0x%lx, x_modify:0x%lx\n",
 240                         i, crc->sg_cpu[i].start_addr,
 241                         crc->sg_cpu[i].cfg, crc->sg_cpu[i].x_count,
 242                         crc->sg_cpu[i].x_modify);
 243                 i++;
 244
 245                 if (mid_dma_count) {
 246                         /* copy extra bytes to next middle dma buffer */
 247                         dma_config = DMAFLOW_ARRAY | RESTART | NDSIZE_3 |
 248                                 DMAEN | PSIZE_32 | WDSIZE_32;
 249                         memcpy(crc->sg_mid_buf + (i << 2),
 250                                 (void *)(dma_addr + (dma_count << 2)),
 251                                 mid_dma_count);
 252                         /* setup new dma descriptor for next middle dma */
 253                         crc->sg_cpu[i].start_addr = dma_map_single(crc->dev,
 254                                         crc->sg_mid_buf + (i << 2),
 255                                         CHKSUM_DIGEST_SIZE, DMA_TO_DEVICE);
 256                         crc->sg_cpu[i].cfg = dma_config;
 257                         crc->sg_cpu[i].x_count = 1;
 258                         crc->sg_cpu[i].x_modify = CHKSUM_DIGEST_SIZE;
 259                         dev_dbg(crc->dev, "%d: crc_dma: start_addr:0x%lx, "
 260                                 "cfg:0x%lx, x_count:0x%lx, x_modify:0x%lx\n",
 261                                 i, crc->sg_cpu[i].start_addr,
 262                                 crc->sg_cpu[i].cfg, crc->sg_cpu[i].x_count,
 263                                 crc->sg_cpu[i].x_modify);
 264                         i++;
 265                 }
 266         }
 267
 268         dma_config = DMAFLOW_ARRAY | RESTART | NDSIZE_3 | DMAEN | PSIZE_32 | WDSIZE_32;
 269         /* For final update req, append the buffer for next update as well*/
 270         if (ctx->bufnext_len && (ctx->flag == CRC_CRYPTO_STATE_FINALUPDATE ||
 271                 ctx->flag == CRC_CRYPTO_STATE_FINISH)) {
 272                 crc->sg_cpu[i].start_addr = dma_map_single(crc->dev, ctx->bufnext,
 273                                                 CHKSUM_DIGEST_SIZE, DMA_TO_DEVICE);
 274                 crc->sg_cpu[i].cfg = dma_config;
 275                 crc->sg_cpu[i].x_count = 1;
 276                 crc->sg_cpu[i].x_modify = CHKSUM_DIGEST_SIZE;
 277                 dev_dbg(crc->dev, "%d: crc_dma: start_addr:0x%lx, "
 278                         "cfg:0x%lx, x_count:0x%lx, x_modify:0x%lx\n",
 279                         i, crc->sg_cpu[i].start_addr,
 280                         crc->sg_cpu[i].cfg, crc->sg_cpu[i].x_count,
 281                         crc->sg_cpu[i].x_modify);
 282                 i++;
 283         }
 284
 285         if (i == 0)
 286                 return;
 287
 288         flush_dcache_range((unsigned int)crc->sg_cpu,
 289                         (unsigned int)crc->sg_cpu +
 290                         i * sizeof(struct dma_desc_array));
 291
 292         /* Set the last descriptor to stop mode */
 293         crc->sg_cpu[i - 1].cfg &= ~(DMAFLOW | NDSIZE);
 294         crc->sg_cpu[i - 1].cfg |= DI_EN;
 295         set_dma_curr_desc_addr(crc->dma_ch, (unsigned long *)crc->sg_dma);
 296         set_dma_x_count(crc->dma_ch, 0);
 297         set_dma_x_modify(crc->dma_ch, 0);
 298         SSYNC();
 299         set_dma_config(crc->dma_ch, dma_config);
 300 }
 301
 302 static int bfin_crypto_crc_handle_queue(struct bfin_crypto_crc *crc,
 303                                   struct ahash_request *req)
 304 {
 305         struct crypto_async_request *async_req, *backlog;
 306         struct bfin_crypto_crc_reqctx *ctx;
 307         struct scatterlist *sg;
 308         int ret = 0;
 309         int nsg, i, j;
 310         unsigned int nextlen;
 311         unsigned long flags;
 312
 313         spin_lock_irqsave(&crc->lock, flags);
 314         if (req)
 315                 ret = ahash_enqueue_request(&crc->queue, req);
 316         if (crc->busy) {
 317                 spin_unlock_irqrestore(&crc->lock, flags);
 318                 return ret;
 319         }
 320         backlog = crypto_get_backlog(&crc->queue);
 321         async_req = crypto_dequeue_request(&crc->queue);
 322         if (async_req)
 323                 crc->busy = 1;
 324         spin_unlock_irqrestore(&crc->lock, flags);
 325
 326         if (!async_req)
 327                 return ret;
 328
 329         if (backlog)
 330                 backlog->complete(backlog, -EINPROGRESS);
 331
 332         req = ahash_request_cast(async_req);
 333         crc->req = req;
 334         ctx = ahash_request_ctx(req);
 335         ctx->sg = NULL;
 336         ctx->sg_buflen = 0;
 337         ctx->sg_nents = 0;
 338
 339         dev_dbg(crc->dev, "handling new req, flag=%u, nbytes: %d\n",
 340                                                 ctx->flag, req->nbytes);
 341
 342         if (ctx->flag == CRC_CRYPTO_STATE_FINISH) {
 343                 if (ctx->bufnext_len == 0) {
 344                         crc->busy = 0;
 345                         return 0;
 346                 }
 347
 348                 /* Pack last crc update buffer to 32bit */
 349                 memset(ctx->bufnext + ctx->bufnext_len, 0,
 350                                 CHKSUM_DIGEST_SIZE - ctx->bufnext_len);
 351         } else {
 352                 /* Pack small data which is less than 32bit to buffer for next update. */
 353                 if (ctx->bufnext_len + req->nbytes < CHKSUM_DIGEST_SIZE) {
 354                         memcpy(ctx->bufnext + ctx->bufnext_len,
 355                                 sg_virt(req->src), req->nbytes);
 356                         ctx->bufnext_len += req->nbytes;
 357                         if (ctx->flag == CRC_CRYPTO_STATE_FINALUPDATE &&
 358                                 ctx->bufnext_len) {
 359                                 goto finish_update;
 360                         } else {
 361                                 crc->busy = 0;
 362                                 return 0;
 363                         }
 364                 }
 365
 366                 if (ctx->bufnext_len) {
 367                         /* Chain in extra bytes of last update */
 368                         ctx->buflast_len = ctx->bufnext_len;
 369                         memcpy(ctx->buflast, ctx->bufnext, ctx->buflast_len);
 370
 371                         nsg = ctx->sg_buflen ? 2 : 1;
 372                         sg_init_table(ctx->bufsl, nsg);
 373                         sg_set_buf(ctx->bufsl, ctx->buflast, ctx->buflast_len);
 374                         if (nsg > 1)
 375                                 scatterwalk_sg_chain(ctx->bufsl, nsg,
 376                                                 req->src);
 377                         ctx->sg = ctx->bufsl;
 378                 } else
 379                         ctx->sg = req->src;
 380
 381                 /* Chop crc buffer size to multiple of 32 bit */
 382                 nsg = ctx->sg_nents = sg_count(ctx->sg);
 383                 ctx->sg_buflen = ctx->buflast_len + req->nbytes;
 384                 ctx->bufnext_len = ctx->sg_buflen % 4;
 385                 ctx->sg_buflen &= ~0x3;
 386
 387                 if (ctx->bufnext_len) {
 388                         /* copy extra bytes to buffer for next update */
 389                         memset(ctx->bufnext, 0, CHKSUM_DIGEST_SIZE);
 390                         nextlen = ctx->bufnext_len;
 391                         for (i = nsg - 1; i >= 0; i--) {
 392                                 sg = sg_get(ctx->sg, nsg, i);
 393                                 j = min(nextlen, sg_dma_len(sg));
 394                                 memcpy(ctx->bufnext + nextlen - j,
 395                                         sg_virt(sg) + sg_dma_len(sg) - j, j);
 396                                 if (j == sg_dma_len(sg))
 397                                         ctx->sg_nents--;
 398                                 nextlen -= j;
 399                                 if (nextlen == 0)
 400                                         break;
 401                         }
 402                 }
 403         }
 404
 405 finish_update:
 406         if (ctx->bufnext_len && (ctx->flag == CRC_CRYPTO_STATE_FINALUPDATE ||
 407                 ctx->flag == CRC_CRYPTO_STATE_FINISH))
 408                 ctx->sg_buflen += CHKSUM_DIGEST_SIZE;
 409
 410         /* set CRC data count before start DMA */
 411         crc->regs->datacnt = ctx->sg_buflen >> 2;
 412
 413         /* setup and enable CRC DMA */
 414         bfin_crypto_crc_config_dma(crc);
 415
 416         /* finally kick off CRC operation */
 417         crc->regs->control |= BLKEN;
 418         SSYNC();
 419
 420         return -EINPROGRESS;
 421 }
 422
 423 static int bfin_crypto_crc_update(struct ahash_request *req)
 424 {
 425         struct bfin_crypto_crc_reqctx *ctx = ahash_request_ctx(req);
 426
 427         if (!req->nbytes)
 428                 return 0;
 429
 430         dev_dbg(ctx->crc->dev, "crc_update\n");
 431         ctx->total += req->nbytes;
 432         ctx->flag = CRC_CRYPTO_STATE_UPDATE;
 433
 434         return bfin_crypto_crc_handle_queue(ctx->crc, req);
 435 }
 436
 437 static int bfin_crypto_crc_final(struct ahash_request *req)
 438 {
 439         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 440         struct bfin_crypto_crc_ctx *crc_ctx = crypto_ahash_ctx(tfm);
 441         struct bfin_crypto_crc_reqctx *ctx = ahash_request_ctx(req);
 442
 443         dev_dbg(ctx->crc->dev, "crc_final\n");
 444         ctx->flag = CRC_CRYPTO_STATE_FINISH;
 445         crc_ctx->key = 0;
 446
 447         return bfin_crypto_crc_handle_queue(ctx->crc, req);
 448 }
 449
 450 static int bfin_crypto_crc_finup(struct ahash_request *req)
 451 {
 452         struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 453         struct bfin_crypto_crc_ctx *crc_ctx = crypto_ahash_ctx(tfm);
 454         struct bfin_crypto_crc_reqctx *ctx = ahash_request_ctx(req);
 455
 456         dev_dbg(ctx->crc->dev, "crc_finishupdate\n");
 457         ctx->total += req->nbytes;
 458         ctx->flag = CRC_CRYPTO_STATE_FINALUPDATE;
 459         crc_ctx->key = 0;
 460
 461         return bfin_crypto_crc_handle_queue(ctx->crc, req);
 462 }
 463
 464 static int bfin_crypto_crc_digest(struct ahash_request *req)
 465 {
 466         int ret;
 467
 468         ret = bfin_crypto_crc_init(req);
 469         if (ret)
 470                 return ret;
 471
 472         return bfin_crypto_crc_finup(req);
 473 }
 474
 475 static int bfin_crypto_crc_setkey(struct crypto_ahash *tfm, const u8 *key,
 476                         unsigned int keylen)
 477 {
 478         struct bfin_crypto_crc_ctx *crc_ctx = crypto_ahash_ctx(tfm);
 479
 480         dev_dbg(crc_ctx->crc->dev, "crc_setkey\n");
 481         if (keylen != CHKSUM_DIGEST_SIZE) {
 482                 crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 483                 return -EINVAL;
 484         }
 485
 486         crc_ctx->key = get_unaligned_le32(key);
 487
 488         return 0;
 489 }
 490
 491 static int bfin_crypto_crc_cra_init(struct crypto_tfm *tfm)
 492 {
 493         struct bfin_crypto_crc_ctx *crc_ctx = crypto_tfm_ctx(tfm);
 494
 495         crc_ctx->key = 0;
 496         crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
 497                                  sizeof(struct bfin_crypto_crc_reqctx));
 498
 499         return 0;
 500 }
 501
 502 static void bfin_crypto_crc_cra_exit(struct crypto_tfm *tfm)
 503 {
 504 }
 505
 506 static struct ahash_alg algs = {
 507         .init           = bfin_crypto_crc_init,
 508         .update         = bfin_crypto_crc_update,
 509         .final          = bfin_crypto_crc_final,
 510         .finup          = bfin_crypto_crc_finup,
 511         .digest         = bfin_crypto_crc_digest,
 512         .setkey         = bfin_crypto_crc_setkey,
 513         .halg.digestsize        = CHKSUM_DIGEST_SIZE,
 514         .halg.base      = {
 515                 .cra_name               = "hmac(crc32)",
 516                 .cra_driver_name        = DRIVER_NAME,
 517                 .cra_priority           = 100,
 518                 .cra_flags              = CRYPTO_ALG_TYPE_AHASH |
 519                                                 CRYPTO_ALG_ASYNC,
 520                 .cra_blocksize          = CHKSUM_BLOCK_SIZE,
 521                 .cra_ctxsize            = sizeof(struct bfin_crypto_crc_ctx),
 522                 .cra_alignmask          = 3,
 523                 .cra_module             = THIS_MODULE,
 524                 .cra_init               = bfin_crypto_crc_cra_init,
 525                 .cra_exit               = bfin_crypto_crc_cra_exit,
 526         }
 527 };
 528
 529 static void bfin_crypto_crc_done_task(unsigned long data)
 530 {
 531         struct bfin_crypto_crc *crc = (struct bfin_crypto_crc *)data;
 532
 533         bfin_crypto_crc_handle_queue(crc, NULL);
 534 }
 535
 536 static irqreturn_t bfin_crypto_crc_handler(int irq, void *dev_id)
 537 {
 538         struct bfin_crypto_crc *crc = dev_id;
 539
 540         if (crc->regs->status & DCNTEXP) {
 541                 crc->regs->status = DCNTEXP;
 542                 SSYNC();
 543
 544                 /* prepare results */
 545                 put_unaligned_le32(crc->regs->result, crc->req->result);
 546
 547                 crc->regs->control &= ~BLKEN;
 548                 crc->busy = 0;
 549
 550                 if (crc->req->base.complete)
 551                         crc->req->base.complete(&crc->req->base, 0);
 552
 553                 tasklet_schedule(&crc->done_task);
 554
 555                 return IRQ_HANDLED;
 556         } else
 557                 return IRQ_NONE;
 558 }
 559
 560 #ifdef CONFIG_PM
 561 /**
 562  *      bfin_crypto_crc_suspend - suspend crc device
 563  *      @pdev: device being suspended
 564  *      @state: requested suspend state
 565  */
 566 static int bfin_crypto_crc_suspend(struct platform_device *pdev, pm_message_t state)
 567 {
 568         struct bfin_crypto_crc *crc = platform_get_drvdata(pdev);
 569         int i = 100000;
 570
 571         while ((crc->regs->control & BLKEN) && --i)
 572                 cpu_relax();
 573
 574         if (i == 0)
 575                 return -EBUSY;
 576
 577         return 0;
 578 }
 579 #else
 580 # define bfin_crypto_crc_suspend NULL
 581 #endif
 582
 583 #define bfin_crypto_crc_resume NULL
 584
 585 /**
 586  *      bfin_crypto_crc_probe - Initialize module
 587  *
 588  */
 589 static int bfin_crypto_crc_probe(struct platform_device *pdev)
 590 {
 591         struct device *dev = &pdev->dev;
 592         struct resource *res;
 593         struct bfin_crypto_crc *crc;
 594         unsigned int timeout = 100000;
 595         int ret;
 596
 597         crc = kzalloc(sizeof(*crc), GFP_KERNEL);
 598         if (!crc) {
 599                 dev_err(&pdev->dev, "fail to malloc bfin_crypto_crc\n");
 600                 return -ENOMEM;
 601         }
 602
 603         crc->dev = dev;
 604
 605         INIT_LIST_HEAD(&crc->list);
 606         spin_lock_init(&crc->lock);
 607         tasklet_init(&crc->done_task, bfin_crypto_crc_done_task, (unsigned long)crc);
 608         crypto_init_queue(&crc->queue, CRC_CCRYPTO_QUEUE_LENGTH);
 609
 610         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 611         if (res == NULL) {
 612                 dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
 613                 ret = -ENOENT;
 614                 goto out_error_free_mem;
 615         }
 616
 617         crc->regs = ioremap(res->start, resource_size(res));
 618         if (!crc->regs) {
 619                 dev_err(&pdev->dev, "Cannot map CRC IO\n");
 620                 ret = -ENXIO;
 621                 goto out_error_free_mem;
 622         }
 623
 624         crc->irq = platform_get_irq(pdev, 0);
 625         if (crc->irq < 0) {
 626                 dev_err(&pdev->dev, "No CRC DCNTEXP IRQ specified\n");
 627                 ret = -ENOENT;
 628                 goto out_error_unmap;
 629         }
 630
 631         ret = request_irq(crc->irq, bfin_crypto_crc_handler, IRQF_SHARED, dev_name(dev), crc);
 632         if (ret) {
 633                 dev_err(&pdev->dev, "Unable to request blackfin crc irq\n");
 634                 goto out_error_unmap;
 635         }
 636
 637         res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
 638         if (res == NULL) {
 639                 dev_err(&pdev->dev, "No CRC DMA channel specified\n");
 640                 ret = -ENOENT;
 641                 goto out_error_irq;
 642         }
 643         crc->dma_ch = res->start;
 644
 645         ret = request_dma(crc->dma_ch, dev_name(dev));
 646         if (ret) {
 647                 dev_err(&pdev->dev, "Unable to attach Blackfin CRC DMA channel\n");
 648                 goto out_error_irq;
 649         }
 650
 651         crc->sg_cpu = dma_alloc_coherent(&pdev->dev, PAGE_SIZE, &crc->sg_dma, GFP_KERNEL);
 652         if (crc->sg_cpu == NULL) {
 653                 ret = -ENOMEM;
 654                 goto out_error_dma;
 655         }
 656         /*
 657          * need at most CRC_MAX_DMA_DESC sg + CRC_MAX_DMA_DESC middle  +
 658          * 1 last + 1 next dma descriptors
 659          */
 660         crc->sg_mid_buf = (u8 *)(crc->sg_cpu + ((CRC_MAX_DMA_DESC + 1) << 1));
 661
 662         crc->regs->control = 0;
 663         SSYNC();
 664         crc->regs->poly = crc->poly = (u32)pdev->dev.platform_data;
 665         SSYNC();
 666
 667         while (!(crc->regs->status & LUTDONE) && (--timeout) > 0)
 668                 cpu_relax();
 669
 670         if (timeout == 0)
 671                 dev_info(&pdev->dev, "init crc poly timeout\n");
 672
 673         spin_lock(&crc_list.lock);
 674         list_add(&crc->list, &crc_list.dev_list);
 675         spin_unlock(&crc_list.lock);
 676
 677         platform_set_drvdata(pdev, crc);
 678
 679         ret = crypto_register_ahash(&algs);
 680         if (ret) {
 681                 spin_lock(&crc_list.lock);
 682                 list_del(&crc->list);
 683                 spin_unlock(&crc_list.lock);
 684                 dev_err(&pdev->dev, "Cann't register crypto ahash device\n");
 685                 goto out_error_dma;
 686         }
 687
 688         dev_info(&pdev->dev, "initialized\n");
 689
 690         return 0;
 691
 692 out_error_dma:
 693         if (crc->sg_cpu)
 694                 dma_free_coherent(&pdev->dev, PAGE_SIZE, crc->sg_cpu, crc->sg_dma);
 695         free_dma(crc->dma_ch);
 696 out_error_irq:
 697         free_irq(crc->irq, crc);
 698 out_error_unmap:
 699         iounmap((void *)crc->regs);
 700 out_error_free_mem:
 701         kfree(crc);
 702
 703         return ret;
 704 }
 705
 706 /**
 707  *      bfin_crypto_crc_remove - Initialize module
 708  *
 709  */
 710 static int bfin_crypto_crc_remove(struct platform_device *pdev)
 711 {
 712         struct bfin_crypto_crc *crc = platform_get_drvdata(pdev);
 713
 714         if (!crc)
 715                 return -ENODEV;
 716
 717         spin_lock(&crc_list.lock);
 718         list_del(&crc->list);
 719         spin_unlock(&crc_list.lock);
 720
 721         crypto_unregister_ahash(&algs);
 722         tasklet_kill(&crc->done_task);
 723         free_dma(crc->dma_ch);
 724         if (crc->irq > 0)
 725                 free_irq(crc->irq, crc);
 726         iounmap((void *)crc->regs);
 727         kfree(crc);
 728
 729         return 0;
 730 }
 731
 732 static struct platform_driver bfin_crypto_crc_driver = {
 733         .probe     = bfin_crypto_crc_probe,
 734         .remove    = bfin_crypto_crc_remove,
 735         .suspend   = bfin_crypto_crc_suspend,
 736         .resume    = bfin_crypto_crc_resume,
 737         .driver    = {
 738                 .name  = DRIVER_NAME,
 739                 .owner = THIS_MODULE,
 740         },
 741 };
 742
 743 /**
 744  *      bfin_crypto_crc_mod_init - Initialize module
 745  *
 746  *      Checks the module params and registers the platform driver.
 747  *      Real work is in the platform probe function.
 748  */
 749 static int __init bfin_crypto_crc_mod_init(void)
 750 {
 751         int ret;
 752
 753         pr_info("Blackfin hardware CRC crypto driver\n");
 754
 755         INIT_LIST_HEAD(&crc_list.dev_list);
 756         spin_lock_init(&crc_list.lock);
 757
 758         ret = platform_driver_register(&bfin_crypto_crc_driver);
 759         if (ret) {
 760                 pr_info(KERN_ERR "unable to register driver\n");
 761                 return ret;
 762         }
 763
 764         return 0;
 765 }
 766
 767 /**
 768  *      bfin_crypto_crc_mod_exit - Deinitialize module
 769  */
 770 static void __exit bfin_crypto_crc_mod_exit(void)
 771 {
 772         platform_driver_unregister(&bfin_crypto_crc_driver);
 773 }
 774
 775 module_init(bfin_crypto_crc_mod_init);
 776 module_exit(bfin_crypto_crc_mod_exit);
 777
 778 MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
 779 MODULE_DESCRIPTION("Blackfin CRC hardware crypto driver");
 780 MODULE_LICENSE("GPL");