drivers/crypto/ccp/ccp-dmaengine.c

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) driver
   3  *
   4  * Copyright (C) 2016 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Gary R Hook <gary.hook@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/dmaengine.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/mutex.h>
  17 #include <linux/ccp.h>
  18
  19 #include "ccp-dev.h"
  20 #include "../../dma/dmaengine.h"
  21
  22 #define CCP_DMA_WIDTH(_mask)            \
  23 ({                                      \
  24         u64 mask = _mask + 1;           \
  25         (mask == 0) ? 64 : fls64(mask); \
  26 })
  27
  28 static void ccp_free_cmd_resources(struct ccp_device *ccp,
  29                                    struct list_head *list)
  30 {
  31         struct ccp_dma_cmd *cmd, *ctmp;
  32
  33         list_for_each_entry_safe(cmd, ctmp, list, entry) {
  34                 list_del(&cmd->entry);
  35                 kmem_cache_free(ccp->dma_cmd_cache, cmd);
  36         }
  37 }
  38
  39 static void ccp_free_desc_resources(struct ccp_device *ccp,
  40                                     struct list_head *list)
  41 {
  42         struct ccp_dma_desc *desc, *dtmp;
  43
  44         list_for_each_entry_safe(desc, dtmp, list, entry) {
  45                 ccp_free_cmd_resources(ccp, &desc->active);
  46                 ccp_free_cmd_resources(ccp, &desc->pending);
  47
  48                 list_del(&desc->entry);
  49                 kmem_cache_free(ccp->dma_desc_cache, desc);
  50         }
  51 }
  52
  53 static void ccp_free_chan_resources(struct dma_chan *dma_chan)
  54 {
  55         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
  56                                                  dma_chan);
  57         unsigned long flags;
  58
  59         dev_dbg(chan->ccp->dev, "%s - chan=%p\n", __func__, chan);
  60
  61         spin_lock_irqsave(&chan->lock, flags);
  62
  63         ccp_free_desc_resources(chan->ccp, &chan->complete);
  64         ccp_free_desc_resources(chan->ccp, &chan->active);
  65         ccp_free_desc_resources(chan->ccp, &chan->pending);
  66         ccp_free_desc_resources(chan->ccp, &chan->created);
  67
  68         spin_unlock_irqrestore(&chan->lock, flags);
  69 }
  70
  71 static void ccp_cleanup_desc_resources(struct ccp_device *ccp,
  72                                        struct list_head *list)
  73 {
  74         struct ccp_dma_desc *desc, *dtmp;
  75
  76         list_for_each_entry_safe_reverse(desc, dtmp, list, entry) {
  77                 if (!async_tx_test_ack(&desc->tx_desc))
  78                         continue;
  79
  80                 dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
  81
  82                 ccp_free_cmd_resources(ccp, &desc->active);
  83                 ccp_free_cmd_resources(ccp, &desc->pending);
  84
  85                 list_del(&desc->entry);
  86                 kmem_cache_free(ccp->dma_desc_cache, desc);
  87         }
  88 }
  89
  90 static void ccp_do_cleanup(unsigned long data)
  91 {
  92         struct ccp_dma_chan *chan = (struct ccp_dma_chan *)data;
  93         unsigned long flags;
  94
  95         dev_dbg(chan->ccp->dev, "%s - chan=%s\n", __func__,
  96                 dma_chan_name(&chan->dma_chan));
  97
  98         spin_lock_irqsave(&chan->lock, flags);
  99
 100         ccp_cleanup_desc_resources(chan->ccp, &chan->complete);
 101
 102         spin_unlock_irqrestore(&chan->lock, flags);
 103 }
 104
 105 static int ccp_issue_next_cmd(struct ccp_dma_desc *desc)
 106 {
 107         struct ccp_dma_cmd *cmd;
 108         int ret;
 109
 110         cmd = list_first_entry(&desc->pending, struct ccp_dma_cmd, entry);
 111         list_move(&cmd->entry, &desc->active);
 112
 113         dev_dbg(desc->ccp->dev, "%s - tx %d, cmd=%p\n", __func__,
 114                 desc->tx_desc.cookie, cmd);
 115
 116         ret = ccp_enqueue_cmd(&cmd->ccp_cmd);
 117         if (!ret || (ret == -EINPROGRESS) || (ret == -EBUSY))
 118                 return 0;
 119
 120         dev_dbg(desc->ccp->dev, "%s - error: ret=%d, tx %d, cmd=%p\n", __func__,
 121                 ret, desc->tx_desc.cookie, cmd);
 122
 123         return ret;
 124 }
 125
 126 static void ccp_free_active_cmd(struct ccp_dma_desc *desc)
 127 {
 128         struct ccp_dma_cmd *cmd;
 129
 130         cmd = list_first_entry_or_null(&desc->active, struct ccp_dma_cmd,
 131                                        entry);
 132         if (!cmd)
 133                 return;
 134
 135         dev_dbg(desc->ccp->dev, "%s - freeing tx %d cmd=%p\n",
 136                 __func__, desc->tx_desc.cookie, cmd);
 137
 138         list_del(&cmd->entry);
 139         kmem_cache_free(desc->ccp->dma_cmd_cache, cmd);
 140 }
 141
 142 static struct ccp_dma_desc *__ccp_next_dma_desc(struct ccp_dma_chan *chan,
 143                                                 struct ccp_dma_desc *desc)
 144 {
 145         /* Move current DMA descriptor to the complete list */
 146         if (desc)
 147                 list_move(&desc->entry, &chan->complete);
 148
 149         /* Get the next DMA descriptor on the active list */
 150         desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
 151                                         entry);
 152
 153         return desc;
 154 }
 155
 156 static struct ccp_dma_desc *ccp_handle_active_desc(struct ccp_dma_chan *chan,
 157                                                    struct ccp_dma_desc *desc)
 158 {
 159         struct dma_async_tx_descriptor *tx_desc;
 160         unsigned long flags;
 161
 162         /* Loop over descriptors until one is found with commands */
 163         do {
 164                 if (desc) {
 165                         /* Remove the DMA command from the list and free it */
 166                         ccp_free_active_cmd(desc);
 167
 168                         if (!list_empty(&desc->pending)) {
 169                                 /* No errors, keep going */
 170                                 if (desc->status != DMA_ERROR)
 171                                         return desc;
 172
 173                                 /* Error, free remaining commands and move on */
 174                                 ccp_free_cmd_resources(desc->ccp,
 175                                                        &desc->pending);
 176                         }
 177
 178                         tx_desc = &desc->tx_desc;
 179                 } else {
 180                         tx_desc = NULL;
 181                 }
 182
 183                 spin_lock_irqsave(&chan->lock, flags);
 184
 185                 if (desc) {
 186                         if (desc->status != DMA_ERROR)
 187                                 desc->status = DMA_COMPLETE;
 188
 189                         dev_dbg(desc->ccp->dev,
 190                                 "%s - tx %d complete, status=%u\n", __func__,
 191                                 desc->tx_desc.cookie, desc->status);
 192
 193                         dma_cookie_complete(tx_desc);
 194                 }
 195
 196                 desc = __ccp_next_dma_desc(chan, desc);
 197
 198                 spin_unlock_irqrestore(&chan->lock, flags);
 199
 200                 if (tx_desc) {
 201                         if (tx_desc->callback &&
 202                             (tx_desc->flags & DMA_PREP_INTERRUPT))
 203                                 tx_desc->callback(tx_desc->callback_param);
 204
 205                         dma_run_dependencies(tx_desc);
 206                 }
 207         } while (desc);
 208
 209         return NULL;
 210 }
 211
 212 static struct ccp_dma_desc *__ccp_pending_to_active(struct ccp_dma_chan *chan)
 213 {
 214         struct ccp_dma_desc *desc;
 215
 216         if (list_empty(&chan->pending))
 217                 return NULL;
 218
 219         desc = list_empty(&chan->active)
 220                 ? list_first_entry(&chan->pending, struct ccp_dma_desc, entry)
 221                 : NULL;
 222
 223         list_splice_tail_init(&chan->pending, &chan->active);
 224
 225         return desc;
 226 }
 227
 228 static void ccp_cmd_callback(void *data, int err)
 229 {
 230         struct ccp_dma_desc *desc = data;
 231         struct ccp_dma_chan *chan;
 232         int ret;
 233
 234         if (err == -EINPROGRESS)
 235                 return;
 236
 237         chan = container_of(desc->tx_desc.chan, struct ccp_dma_chan,
 238                             dma_chan);
 239
 240         dev_dbg(chan->ccp->dev, "%s - tx %d callback, err=%d\n",
 241                 __func__, desc->tx_desc.cookie, err);
 242
 243         if (err)
 244                 desc->status = DMA_ERROR;
 245
 246         while (true) {
 247                 /* Check for DMA descriptor completion */
 248                 desc = ccp_handle_active_desc(chan, desc);
 249
 250                 /* Don't submit cmd if no descriptor or DMA is paused */
 251                 if (!desc || (chan->status == DMA_PAUSED))
 252                         break;
 253
 254                 ret = ccp_issue_next_cmd(desc);
 255                 if (!ret)
 256                         break;
 257
 258                 desc->status = DMA_ERROR;
 259         }
 260
 261         tasklet_schedule(&chan->cleanup_tasklet);
 262 }
 263
 264 static dma_cookie_t ccp_tx_submit(struct dma_async_tx_descriptor *tx_desc)
 265 {
 266         struct ccp_dma_desc *desc = container_of(tx_desc, struct ccp_dma_desc,
 267                                                  tx_desc);
 268         struct ccp_dma_chan *chan;
 269         dma_cookie_t cookie;
 270         unsigned long flags;
 271
 272         chan = container_of(tx_desc->chan, struct ccp_dma_chan, dma_chan);
 273
 274         spin_lock_irqsave(&chan->lock, flags);
 275
 276         cookie = dma_cookie_assign(tx_desc);
 277         list_del(&desc->entry);
 278         list_add_tail(&desc->entry, &chan->pending);
 279
 280         spin_unlock_irqrestore(&chan->lock, flags);
 281
 282         dev_dbg(chan->ccp->dev, "%s - added tx descriptor %d to pending list\n",
 283                 __func__, cookie);
 284
 285         return cookie;
 286 }
 287
 288 static struct ccp_dma_cmd *ccp_alloc_dma_cmd(struct ccp_dma_chan *chan)
 289 {
 290         struct ccp_dma_cmd *cmd;
 291
 292         cmd = kmem_cache_alloc(chan->ccp->dma_cmd_cache, GFP_NOWAIT);
 293         if (cmd)
 294                 memset(cmd, 0, sizeof(*cmd));
 295
 296         return cmd;
 297 }
 298
 299 static struct ccp_dma_desc *ccp_alloc_dma_desc(struct ccp_dma_chan *chan,
 300                                                unsigned long flags)
 301 {
 302         struct ccp_dma_desc *desc;
 303
 304         desc = kmem_cache_zalloc(chan->ccp->dma_desc_cache, GFP_NOWAIT);
 305         if (!desc)
 306                 return NULL;
 307
 308         dma_async_tx_descriptor_init(&desc->tx_desc, &chan->dma_chan);
 309         desc->tx_desc.flags = flags;
 310         desc->tx_desc.tx_submit = ccp_tx_submit;
 311         desc->ccp = chan->ccp;
 312         INIT_LIST_HEAD(&desc->pending);
 313         INIT_LIST_HEAD(&desc->active);
 314         desc->status = DMA_IN_PROGRESS;
 315
 316         return desc;
 317 }
 318
 319 static struct ccp_dma_desc *ccp_create_desc(struct dma_chan *dma_chan,
 320                                             struct scatterlist *dst_sg,
 321                                             unsigned int dst_nents,
 322                                             struct scatterlist *src_sg,
 323                                             unsigned int src_nents,
 324                                             unsigned long flags)
 325 {
 326         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 327                                                  dma_chan);
 328         struct ccp_device *ccp = chan->ccp;
 329         struct ccp_dma_desc *desc;
 330         struct ccp_dma_cmd *cmd;
 331         struct ccp_cmd *ccp_cmd;
 332         struct ccp_passthru_nomap_engine *ccp_pt;
 333         unsigned int src_offset, src_len;
 334         unsigned int dst_offset, dst_len;
 335         unsigned int len;
 336         unsigned long sflags;
 337         size_t total_len;
 338
 339         if (!dst_sg || !src_sg)
 340                 return NULL;
 341
 342         if (!dst_nents || !src_nents)
 343                 return NULL;
 344
 345         desc = ccp_alloc_dma_desc(chan, flags);
 346         if (!desc)
 347                 return NULL;
 348
 349         total_len = 0;
 350
 351         src_len = sg_dma_len(src_sg);
 352         src_offset = 0;
 353
 354         dst_len = sg_dma_len(dst_sg);
 355         dst_offset = 0;
 356
 357         while (true) {
 358                 if (!src_len) {
 359                         src_nents--;
 360                         if (!src_nents)
 361                                 break;
 362
 363                         src_sg = sg_next(src_sg);
 364                         if (!src_sg)
 365                                 break;
 366
 367                         src_len = sg_dma_len(src_sg);
 368                         src_offset = 0;
 369                         continue;
 370                 }
 371
 372                 if (!dst_len) {
 373                         dst_nents--;
 374                         if (!dst_nents)
 375                                 break;
 376
 377                         dst_sg = sg_next(dst_sg);
 378                         if (!dst_sg)
 379                                 break;
 380
 381                         dst_len = sg_dma_len(dst_sg);
 382                         dst_offset = 0;
 383                         continue;
 384                 }
 385
 386                 len = min(dst_len, src_len);
 387
 388                 cmd = ccp_alloc_dma_cmd(chan);
 389                 if (!cmd)
 390                         goto err;
 391
 392                 ccp_cmd = &cmd->ccp_cmd;
 393                 ccp_cmd->ccp = chan->ccp;
 394                 ccp_pt = &ccp_cmd->u.passthru_nomap;
 395                 ccp_cmd->flags = CCP_CMD_MAY_BACKLOG;
 396                 ccp_cmd->flags |= CCP_CMD_PASSTHRU_NO_DMA_MAP;
 397                 ccp_cmd->engine = CCP_ENGINE_PASSTHRU;
 398                 ccp_pt->bit_mod = CCP_PASSTHRU_BITWISE_NOOP;
 399                 ccp_pt->byte_swap = CCP_PASSTHRU_BYTESWAP_NOOP;
 400                 ccp_pt->src_dma = sg_dma_address(src_sg) + src_offset;
 401                 ccp_pt->dst_dma = sg_dma_address(dst_sg) + dst_offset;
 402                 ccp_pt->src_len = len;
 403                 ccp_pt->final = 1;
 404                 ccp_cmd->callback = ccp_cmd_callback;
 405                 ccp_cmd->data = desc;
 406
 407                 list_add_tail(&cmd->entry, &desc->pending);
 408
 409                 dev_dbg(ccp->dev,
 410                         "%s - cmd=%p, src=%pad, dst=%pad, len=%llu\n", __func__,
 411                         cmd, &ccp_pt->src_dma,
 412                         &ccp_pt->dst_dma, ccp_pt->src_len);
 413
 414                 total_len += len;
 415
 416                 src_len -= len;
 417                 src_offset += len;
 418
 419                 dst_len -= len;
 420                 dst_offset += len;
 421         }
 422
 423         desc->len = total_len;
 424
 425         if (list_empty(&desc->pending))
 426                 goto err;
 427
 428         dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
 429
 430         spin_lock_irqsave(&chan->lock, sflags);
 431
 432         list_add_tail(&desc->entry, &chan->created);
 433
 434         spin_unlock_irqrestore(&chan->lock, sflags);
 435
 436         return desc;
 437
 438 err:
 439         ccp_free_cmd_resources(ccp, &desc->pending);
 440         kmem_cache_free(ccp->dma_desc_cache, desc);
 441
 442         return NULL;
 443 }
 444
 445 static struct dma_async_tx_descriptor *ccp_prep_dma_memcpy(
 446         struct dma_chan *dma_chan, dma_addr_t dst, dma_addr_t src, size_t len,
 447         unsigned long flags)
 448 {
 449         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 450                                                  dma_chan);
 451         struct ccp_dma_desc *desc;
 452         struct scatterlist dst_sg, src_sg;
 453
 454         dev_dbg(chan->ccp->dev,
 455                 "%s - src=%pad, dst=%pad, len=%zu, flags=%#lx\n",
 456                 __func__, &src, &dst, len, flags);
 457
 458         sg_init_table(&dst_sg, 1);
 459         sg_dma_address(&dst_sg) = dst;
 460         sg_dma_len(&dst_sg) = len;
 461
 462         sg_init_table(&src_sg, 1);
 463         sg_dma_address(&src_sg) = src;
 464         sg_dma_len(&src_sg) = len;
 465
 466         desc = ccp_create_desc(dma_chan, &dst_sg, 1, &src_sg, 1, flags);
 467         if (!desc)
 468                 return NULL;
 469
 470         return &desc->tx_desc;
 471 }
 472
 473 static struct dma_async_tx_descriptor *ccp_prep_dma_sg(
 474         struct dma_chan *dma_chan, struct scatterlist *dst_sg,
 475         unsigned int dst_nents, struct scatterlist *src_sg,
 476         unsigned int src_nents, unsigned long flags)
 477 {
 478         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 479                                                  dma_chan);
 480         struct ccp_dma_desc *desc;
 481
 482         dev_dbg(chan->ccp->dev,
 483                 "%s - src=%p, src_nents=%u dst=%p, dst_nents=%u, flags=%#lx\n",
 484                 __func__, src_sg, src_nents, dst_sg, dst_nents, flags);
 485
 486         desc = ccp_create_desc(dma_chan, dst_sg, dst_nents, src_sg, src_nents,
 487                                flags);
 488         if (!desc)
 489                 return NULL;
 490
 491         return &desc->tx_desc;
 492 }
 493
 494 static struct dma_async_tx_descriptor *ccp_prep_dma_interrupt(
 495         struct dma_chan *dma_chan, unsigned long flags)
 496 {
 497         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 498                                                  dma_chan);
 499         struct ccp_dma_desc *desc;
 500
 501         desc = ccp_alloc_dma_desc(chan, flags);
 502         if (!desc)
 503                 return NULL;
 504
 505         return &desc->tx_desc;
 506 }
 507
 508 static void ccp_issue_pending(struct dma_chan *dma_chan)
 509 {
 510         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 511                                                  dma_chan);
 512         struct ccp_dma_desc *desc;
 513         unsigned long flags;
 514
 515         dev_dbg(chan->ccp->dev, "%s\n", __func__);
 516
 517         spin_lock_irqsave(&chan->lock, flags);
 518
 519         desc = __ccp_pending_to_active(chan);
 520
 521         spin_unlock_irqrestore(&chan->lock, flags);
 522
 523         /* If there was nothing active, start processing */
 524         if (desc)
 525                 ccp_cmd_callback(desc, 0);
 526 }
 527
 528 static enum dma_status ccp_tx_status(struct dma_chan *dma_chan,
 529                                      dma_cookie_t cookie,
 530                                      struct dma_tx_state *state)
 531 {
 532         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 533                                                  dma_chan);
 534         struct ccp_dma_desc *desc;
 535         enum dma_status ret;
 536         unsigned long flags;
 537
 538         if (chan->status == DMA_PAUSED) {
 539                 ret = DMA_PAUSED;
 540                 goto out;
 541         }
 542
 543         ret = dma_cookie_status(dma_chan, cookie, state);
 544         if (ret == DMA_COMPLETE) {
 545                 spin_lock_irqsave(&chan->lock, flags);
 546
 547                 /* Get status from complete chain, if still there */
 548                 list_for_each_entry(desc, &chan->complete, entry) {
 549                         if (desc->tx_desc.cookie != cookie)
 550                                 continue;
 551
 552                         ret = desc->status;
 553                         break;
 554                 }
 555
 556                 spin_unlock_irqrestore(&chan->lock, flags);
 557         }
 558
 559 out:
 560         dev_dbg(chan->ccp->dev, "%s - %u\n", __func__, ret);
 561
 562         return ret;
 563 }
 564
 565 static int ccp_pause(struct dma_chan *dma_chan)
 566 {
 567         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 568                                                  dma_chan);
 569
 570         chan->status = DMA_PAUSED;
 571
 572         /*TODO: Wait for active DMA to complete before returning? */
 573
 574         return 0;
 575 }
 576
 577 static int ccp_resume(struct dma_chan *dma_chan)
 578 {
 579         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 580                                                  dma_chan);
 581         struct ccp_dma_desc *desc;
 582         unsigned long flags;
 583
 584         spin_lock_irqsave(&chan->lock, flags);
 585
 586         desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
 587                                         entry);
 588
 589         spin_unlock_irqrestore(&chan->lock, flags);
 590
 591         /* Indicate the channel is running again */
 592         chan->status = DMA_IN_PROGRESS;
 593
 594         /* If there was something active, re-start */
 595         if (desc)
 596                 ccp_cmd_callback(desc, 0);
 597
 598         return 0;
 599 }
 600
 601 static int ccp_terminate_all(struct dma_chan *dma_chan)
 602 {
 603         struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
 604                                                  dma_chan);
 605         unsigned long flags;
 606
 607         dev_dbg(chan->ccp->dev, "%s\n", __func__);
 608
 609         /*TODO: Wait for active DMA to complete before continuing */
 610
 611         spin_lock_irqsave(&chan->lock, flags);
 612
 613         /*TODO: Purge the complete list? */
 614         ccp_free_desc_resources(chan->ccp, &chan->active);
 615         ccp_free_desc_resources(chan->ccp, &chan->pending);
 616         ccp_free_desc_resources(chan->ccp, &chan->created);
 617
 618         spin_unlock_irqrestore(&chan->lock, flags);
 619
 620         return 0;
 621 }
 622
 623 int ccp_dmaengine_register(struct ccp_device *ccp)
 624 {
 625         struct ccp_dma_chan *chan;
 626         struct dma_device *dma_dev = &ccp->dma_dev;
 627         struct dma_chan *dma_chan;
 628         char *dma_cmd_cache_name;
 629         char *dma_desc_cache_name;
 630         unsigned int i;
 631         int ret;
 632
 633         ccp->ccp_dma_chan = devm_kcalloc(ccp->dev, ccp->cmd_q_count,
 634                                          sizeof(*(ccp->ccp_dma_chan)),
 635                                          GFP_KERNEL);
 636         if (!ccp->ccp_dma_chan)
 637                 return -ENOMEM;
 638
 639         dma_cmd_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
 640                                             "%s-dmaengine-cmd-cache",
 641                                             ccp->name);
 642         if (!dma_cmd_cache_name)
 643                 return -ENOMEM;
 644
 645         ccp->dma_cmd_cache = kmem_cache_create(dma_cmd_cache_name,
 646                                                sizeof(struct ccp_dma_cmd),
 647                                                sizeof(void *),
 648                                                SLAB_HWCACHE_ALIGN, NULL);
 649         if (!ccp->dma_cmd_cache)
 650                 return -ENOMEM;
 651
 652         dma_desc_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
 653                                              "%s-dmaengine-desc-cache",
 654                                              ccp->name);
 655         if (!dma_desc_cache_name) {
 656                 ret = -ENOMEM;
 657                 goto err_cache;
 658         }
 659
 660         ccp->dma_desc_cache = kmem_cache_create(dma_desc_cache_name,
 661                                                 sizeof(struct ccp_dma_desc),
 662                                                 sizeof(void *),
 663                                                 SLAB_HWCACHE_ALIGN, NULL);
 664         if (!ccp->dma_desc_cache) {
 665                 ret = -ENOMEM;
 666                 goto err_cache;
 667         }
 668
 669         dma_dev->dev = ccp->dev;
 670         dma_dev->src_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
 671         dma_dev->dst_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
 672         dma_dev->directions = DMA_MEM_TO_MEM;
 673         dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
 674         dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
 675         dma_cap_set(DMA_SG, dma_dev->cap_mask);
 676         dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
 677
 678         INIT_LIST_HEAD(&dma_dev->channels);
 679         for (i = 0; i < ccp->cmd_q_count; i++) {
 680                 chan = ccp->ccp_dma_chan + i;
 681                 dma_chan = &chan->dma_chan;
 682
 683                 chan->ccp = ccp;
 684
 685                 spin_lock_init(&chan->lock);
 686                 INIT_LIST_HEAD(&chan->created);
 687                 INIT_LIST_HEAD(&chan->pending);
 688                 INIT_LIST_HEAD(&chan->active);
 689                 INIT_LIST_HEAD(&chan->complete);
 690
 691                 tasklet_init(&chan->cleanup_tasklet, ccp_do_cleanup,
 692                              (unsigned long)chan);
 693
 694                 dma_chan->device = dma_dev;
 695                 dma_cookie_init(dma_chan);
 696
 697                 list_add_tail(&dma_chan->device_node, &dma_dev->channels);
 698         }
 699
 700         dma_dev->device_free_chan_resources = ccp_free_chan_resources;
 701         dma_dev->device_prep_dma_memcpy = ccp_prep_dma_memcpy;
 702         dma_dev->device_prep_dma_sg = ccp_prep_dma_sg;
 703         dma_dev->device_prep_dma_interrupt = ccp_prep_dma_interrupt;
 704         dma_dev->device_issue_pending = ccp_issue_pending;
 705         dma_dev->device_tx_status = ccp_tx_status;
 706         dma_dev->device_pause = ccp_pause;
 707         dma_dev->device_resume = ccp_resume;
 708         dma_dev->device_terminate_all = ccp_terminate_all;
 709
 710         ret = dma_async_device_register(dma_dev);
 711         if (ret)
 712                 goto err_reg;
 713
 714         return 0;
 715
 716 err_reg:
 717         kmem_cache_destroy(ccp->dma_desc_cache);
 718
 719 err_cache:
 720         kmem_cache_destroy(ccp->dma_cmd_cache);
 721
 722         return ret;
 723 }
 724
 725 void ccp_dmaengine_unregister(struct ccp_device *ccp)
 726 {
 727         struct dma_device *dma_dev = &ccp->dma_dev;
 728
 729         dma_async_device_unregister(dma_dev);
 730
 731         kmem_cache_destroy(ccp->dma_desc_cache);
 732         kmem_cache_destroy(ccp->dma_cmd_cache);
 733 }