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