drivers/dma/iop-adma.c

   1 /*
   2  * offload engine driver for the Intel Xscale series of i/o processors
   3  * Copyright © 2006, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  */
  19
  20 /*
  21  * This driver supports the asynchrounous DMA copy and RAID engines available
  22  * on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x)
  23  */
  24
  25 #include <linux/init.h>
  26 #include <linux/module.h>
  27 #include <linux/delay.h>
  28 #include <linux/dma-mapping.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/memory.h>
  33 #include <linux/ioport.h>
  34 #include <linux/raid/pq.h>
  35
  36 #include <mach/adma.h>
  37
  38 #define to_iop_adma_chan(chan) container_of(chan, struct iop_adma_chan, common)
  39 #define to_iop_adma_device(dev) \
  40         container_of(dev, struct iop_adma_device, common)
  41 #define tx_to_iop_adma_slot(tx) \
  42         container_of(tx, struct iop_adma_desc_slot, async_tx)
  43
  44 /**
  45  * iop_adma_free_slots - flags descriptor slots for reuse
  46  * @slot: Slot to free
  47  * Caller must hold &iop_chan->lock while calling this function
  48  */
  49 static void iop_adma_free_slots(struct iop_adma_desc_slot *slot)
  50 {
  51         int stride = slot->slots_per_op;
  52
  53         while (stride--) {
  54                 slot->slots_per_op = 0;
  55                 slot = list_entry(slot->slot_node.next,
  56                                 struct iop_adma_desc_slot,
  57                                 slot_node);
  58         }
  59 }
  60
  61 static void
  62 iop_desc_unmap(struct iop_adma_chan *iop_chan, struct iop_adma_desc_slot *desc)
  63 {
  64         struct dma_async_tx_descriptor *tx = &desc->async_tx;
  65         struct iop_adma_desc_slot *unmap = desc->group_head;
  66         struct device *dev = &iop_chan->device->pdev->dev;
  67         u32 len = unmap->unmap_len;
  68         enum dma_ctrl_flags flags = tx->flags;
  69         u32 src_cnt;
  70         dma_addr_t addr;
  71         dma_addr_t dest;
  72
  73         src_cnt = unmap->unmap_src_cnt;
  74         dest = iop_desc_get_dest_addr(unmap, iop_chan);
  75         if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
  76                 enum dma_data_direction dir;
  77
  78                 if (src_cnt > 1) /* is xor? */
  79                         dir = DMA_BIDIRECTIONAL;
  80                 else
  81                         dir = DMA_FROM_DEVICE;
  82
  83                 dma_unmap_page(dev, dest, len, dir);
  84         }
  85
  86         if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
  87                 while (src_cnt--) {
  88                         addr = iop_desc_get_src_addr(unmap, iop_chan, src_cnt);
  89                         if (addr == dest)
  90                                 continue;
  91                         dma_unmap_page(dev, addr, len, DMA_TO_DEVICE);
  92                 }
  93         }
  94         desc->group_head = NULL;
  95 }
  96
  97 static void
  98 iop_desc_unmap_pq(struct iop_adma_chan *iop_chan, struct iop_adma_desc_slot *desc)
  99 {
 100         struct dma_async_tx_descriptor *tx = &desc->async_tx;
 101         struct iop_adma_desc_slot *unmap = desc->group_head;
 102         struct device *dev = &iop_chan->device->pdev->dev;
 103         u32 len = unmap->unmap_len;
 104         enum dma_ctrl_flags flags = tx->flags;
 105         u32 src_cnt = unmap->unmap_src_cnt;
 106         dma_addr_t pdest = iop_desc_get_dest_addr(unmap, iop_chan);
 107         dma_addr_t qdest = iop_desc_get_qdest_addr(unmap, iop_chan);
 108         int i;
 109
 110         if (tx->flags & DMA_PREP_CONTINUE)
 111                 src_cnt -= 3;
 112
 113         if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP) && !desc->pq_check_result) {
 114                 dma_unmap_page(dev, pdest, len, DMA_BIDIRECTIONAL);
 115                 dma_unmap_page(dev, qdest, len, DMA_BIDIRECTIONAL);
 116         }
 117
 118         if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
 119                 dma_addr_t addr;
 120
 121                 for (i = 0; i < src_cnt; i++) {
 122                         addr = iop_desc_get_src_addr(unmap, iop_chan, i);
 123                         dma_unmap_page(dev, addr, len, DMA_TO_DEVICE);
 124                 }
 125                 if (desc->pq_check_result) {
 126                         dma_unmap_page(dev, pdest, len, DMA_TO_DEVICE);
 127                         dma_unmap_page(dev, qdest, len, DMA_TO_DEVICE);
 128                 }
 129         }
 130
 131         desc->group_head = NULL;
 132 }
 133
 134
 135 static dma_cookie_t
 136 iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc,
 137         struct iop_adma_chan *iop_chan, dma_cookie_t cookie)
 138 {
 139         struct dma_async_tx_descriptor *tx = &desc->async_tx;
 140
 141         BUG_ON(tx->cookie < 0);
 142         if (tx->cookie > 0) {
 143                 cookie = tx->cookie;
 144                 tx->cookie = 0;
 145
 146                 /* call the callback (must not sleep or submit new
 147                  * operations to this channel)
 148                  */
 149                 if (tx->callback)
 150                         tx->callback(tx->callback_param);
 151
 152                 /* unmap dma addresses
 153                  * (unmap_single vs unmap_page?)
 154                  */
 155                 if (desc->group_head && desc->unmap_len) {
 156                         if (iop_desc_is_pq(desc))
 157                                 iop_desc_unmap_pq(iop_chan, desc);
 158                         else
 159                                 iop_desc_unmap(iop_chan, desc);
 160                 }
 161         }
 162
 163         /* run dependent operations */
 164         dma_run_dependencies(tx);
 165
 166         return cookie;
 167 }
 168
 169 static int
 170 iop_adma_clean_slot(struct iop_adma_desc_slot *desc,
 171         struct iop_adma_chan *iop_chan)
 172 {
 173         /* the client is allowed to attach dependent operations
 174          * until 'ack' is set
 175          */
 176         if (!async_tx_test_ack(&desc->async_tx))
 177                 return 0;
 178
 179         /* leave the last descriptor in the chain
 180          * so we can append to it
 181          */
 182         if (desc->chain_node.next == &iop_chan->chain)
 183                 return 1;
 184
 185         dev_dbg(iop_chan->device->common.dev,
 186                 "\tfree slot: %d slots_per_op: %d\n",
 187                 desc->idx, desc->slots_per_op);
 188
 189         list_del(&desc->chain_node);
 190         iop_adma_free_slots(desc);
 191
 192         return 0;
 193 }
 194
 195 static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 196 {
 197         struct iop_adma_desc_slot *iter, *_iter, *grp_start = NULL;
 198         dma_cookie_t cookie = 0;
 199         u32 current_desc = iop_chan_get_current_descriptor(iop_chan);
 200         int busy = iop_chan_is_busy(iop_chan);
 201         int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
 202
 203         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
 204         /* free completed slots from the chain starting with
 205          * the oldest descriptor
 206          */
 207         list_for_each_entry_safe(iter, _iter, &iop_chan->chain,
 208                                         chain_node) {
 209                 pr_debug("\tcookie: %d slot: %d busy: %d "
 210                         "this_desc: %#x next_desc: %#x ack: %d\n",
 211                         iter->async_tx.cookie, iter->idx, busy,
 212                         iter->async_tx.phys, iop_desc_get_next_desc(iter),
 213                         async_tx_test_ack(&iter->async_tx));
 214                 prefetch(_iter);
 215                 prefetch(&_iter->async_tx);
 216
 217                 /* do not advance past the current descriptor loaded into the
 218                  * hardware channel, subsequent descriptors are either in
 219                  * process or have not been submitted
 220                  */
 221                 if (seen_current)
 222                         break;
 223
 224                 /* stop the search if we reach the current descriptor and the
 225                  * channel is busy, or if it appears that the current descriptor
 226                  * needs to be re-read (i.e. has been appended to)
 227                  */
 228                 if (iter->async_tx.phys == current_desc) {
 229                         BUG_ON(seen_current++);
 230                         if (busy || iop_desc_get_next_desc(iter))
 231                                 break;
 232                 }
 233
 234                 /* detect the start of a group transaction */
 235                 if (!slot_cnt && !slots_per_op) {
 236                         slot_cnt = iter->slot_cnt;
 237                         slots_per_op = iter->slots_per_op;
 238                         if (slot_cnt <= slots_per_op) {
 239                                 slot_cnt = 0;
 240                                 slots_per_op = 0;
 241                         }
 242                 }
 243
 244                 if (slot_cnt) {
 245                         pr_debug("\tgroup++\n");
 246                         if (!grp_start)
 247                                 grp_start = iter;
 248                         slot_cnt -= slots_per_op;
 249                 }
 250
 251                 /* all the members of a group are complete */
 252                 if (slots_per_op != 0 && slot_cnt == 0) {
 253                         struct iop_adma_desc_slot *grp_iter, *_grp_iter;
 254                         int end_of_chain = 0;
 255                         pr_debug("\tgroup end\n");
 256
 257                         /* collect the total results */
 258                         if (grp_start->xor_check_result) {
 259                                 u32 zero_sum_result = 0;
 260                                 slot_cnt = grp_start->slot_cnt;
 261                                 grp_iter = grp_start;
 262
 263                                 list_for_each_entry_from(grp_iter,
 264                                         &iop_chan->chain, chain_node) {
 265                                         zero_sum_result |=
 266                                             iop_desc_get_zero_result(grp_iter);
 267                                             pr_debug("\titer%d result: %d\n",
 268                                             grp_iter->idx, zero_sum_result);
 269                                         slot_cnt -= slots_per_op;
 270                                         if (slot_cnt == 0)
 271                                                 break;
 272                                 }
 273                                 pr_debug("\tgrp_start->xor_check_result: %p\n",
 274                                         grp_start->xor_check_result);
 275                                 *grp_start->xor_check_result = zero_sum_result;
 276                         }
 277
 278                         /* clean up the group */
 279                         slot_cnt = grp_start->slot_cnt;
 280                         grp_iter = grp_start;
 281                         list_for_each_entry_safe_from(grp_iter, _grp_iter,
 282                                 &iop_chan->chain, chain_node) {
 283                                 cookie = iop_adma_run_tx_complete_actions(
 284                                         grp_iter, iop_chan, cookie);
 285
 286                                 slot_cnt -= slots_per_op;
 287                                 end_of_chain = iop_adma_clean_slot(grp_iter,
 288                                         iop_chan);
 289
 290                                 if (slot_cnt == 0 || end_of_chain)
 291                                         break;
 292                         }
 293
 294                         /* the group should be complete at this point */
 295                         BUG_ON(slot_cnt);
 296
 297                         slots_per_op = 0;
 298                         grp_start = NULL;
 299                         if (end_of_chain)
 300                                 break;
 301                         else
 302                                 continue;
 303                 } else if (slots_per_op) /* wait for group completion */
 304                         continue;
 305
 306                 /* write back zero sum results (single descriptor case) */
 307                 if (iter->xor_check_result && iter->async_tx.cookie)
 308                         *iter->xor_check_result =
 309                                 iop_desc_get_zero_result(iter);
 310
 311                 cookie = iop_adma_run_tx_complete_actions(
 312                                         iter, iop_chan, cookie);
 313
 314                 if (iop_adma_clean_slot(iter, iop_chan))
 315                         break;
 316         }
 317
 318         if (cookie > 0) {
 319                 iop_chan->completed_cookie = cookie;
 320                 pr_debug("\tcompleted cookie %d\n", cookie);
 321         }
 322 }
 323
 324 static void
 325 iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 326 {
 327         spin_lock_bh(&iop_chan->lock);
 328         __iop_adma_slot_cleanup(iop_chan);
 329         spin_unlock_bh(&iop_chan->lock);
 330 }
 331
 332 static void iop_adma_tasklet(unsigned long data)
 333 {
 334         struct iop_adma_chan *iop_chan = (struct iop_adma_chan *) data;
 335
 336         /* lockdep will flag depedency submissions as potentially
 337          * recursive locking, this is not the case as a dependency
 338          * submission will never recurse a channels submit routine.
 339          * There are checks in async_tx.c to prevent this.
 340          */
 341         spin_lock_nested(&iop_chan->lock, SINGLE_DEPTH_NESTING);
 342         __iop_adma_slot_cleanup(iop_chan);
 343         spin_unlock(&iop_chan->lock);
 344 }
 345
 346 static struct iop_adma_desc_slot *
 347 iop_adma_alloc_slots(struct iop_adma_chan *iop_chan, int num_slots,
 348                         int slots_per_op)
 349 {
 350         struct iop_adma_desc_slot *iter, *_iter, *alloc_start = NULL;
 351         LIST_HEAD(chain);
 352         int slots_found, retry = 0;
 353
 354         /* start search from the last allocated descrtiptor
 355          * if a contiguous allocation can not be found start searching
 356          * from the beginning of the list
 357          */
 358 retry:
 359         slots_found = 0;
 360         if (retry == 0)
 361                 iter = iop_chan->last_used;
 362         else
 363                 iter = list_entry(&iop_chan->all_slots,
 364                         struct iop_adma_desc_slot,
 365                         slot_node);
 366
 367         list_for_each_entry_safe_continue(
 368                 iter, _iter, &iop_chan->all_slots, slot_node) {
 369                 prefetch(_iter);
 370                 prefetch(&_iter->async_tx);
 371                 if (iter->slots_per_op) {
 372                         /* give up after finding the first busy slot
 373                          * on the second pass through the list
 374                          */
 375                         if (retry)
 376                                 break;
 377
 378                         slots_found = 0;
 379                         continue;
 380                 }
 381
 382                 /* start the allocation if the slot is correctly aligned */
 383                 if (!slots_found++) {
 384                         if (iop_desc_is_aligned(iter, slots_per_op))
 385                                 alloc_start = iter;
 386                         else {
 387                                 slots_found = 0;
 388                                 continue;
 389                         }
 390                 }
 391
 392                 if (slots_found == num_slots) {
 393                         struct iop_adma_desc_slot *alloc_tail = NULL;
 394                         struct iop_adma_desc_slot *last_used = NULL;
 395                         iter = alloc_start;
 396                         while (num_slots) {
 397                                 int i;
 398                                 dev_dbg(iop_chan->device->common.dev,
 399                                         "allocated slot: %d "
 400                                         "(desc %p phys: %#x) slots_per_op %d\n",
 401                                         iter->idx, iter->hw_desc,
 402                                         iter->async_tx.phys, slots_per_op);
 403
 404                                 /* pre-ack all but the last descriptor */
 405                                 if (num_slots != slots_per_op)
 406                                         async_tx_ack(&iter->async_tx);
 407
 408                                 list_add_tail(&iter->chain_node, &chain);
 409                                 alloc_tail = iter;
 410                                 iter->async_tx.cookie = 0;
 411                                 iter->slot_cnt = num_slots;
 412                                 iter->xor_check_result = NULL;
 413                                 for (i = 0; i < slots_per_op; i++) {
 414                                         iter->slots_per_op = slots_per_op - i;
 415                                         last_used = iter;
 416                                         iter = list_entry(iter->slot_node.next,
 417                                                 struct iop_adma_desc_slot,
 418                                                 slot_node);
 419                                 }
 420                                 num_slots -= slots_per_op;
 421                         }
 422                         alloc_tail->group_head = alloc_start;
 423                         alloc_tail->async_tx.cookie = -EBUSY;
 424                         list_splice(&chain, &alloc_tail->tx_list);
 425                         iop_chan->last_used = last_used;
 426                         iop_desc_clear_next_desc(alloc_start);
 427                         iop_desc_clear_next_desc(alloc_tail);
 428                         return alloc_tail;
 429                 }
 430         }
 431         if (!retry++)
 432                 goto retry;
 433
 434         /* perform direct reclaim if the allocation fails */
 435         __iop_adma_slot_cleanup(iop_chan);
 436
 437         return NULL;
 438 }
 439
 440 static dma_cookie_t
 441 iop_desc_assign_cookie(struct iop_adma_chan *iop_chan,
 442         struct iop_adma_desc_slot *desc)
 443 {
 444         dma_cookie_t cookie = iop_chan->common.cookie;
 445         cookie++;
 446         if (cookie < 0)
 447                 cookie = 1;
 448         iop_chan->common.cookie = desc->async_tx.cookie = cookie;
 449         return cookie;
 450 }
 451
 452 static void iop_adma_check_threshold(struct iop_adma_chan *iop_chan)
 453 {
 454         dev_dbg(iop_chan->device->common.dev, "pending: %d\n",
 455                 iop_chan->pending);
 456
 457         if (iop_chan->pending >= IOP_ADMA_THRESHOLD) {
 458                 iop_chan->pending = 0;
 459                 iop_chan_append(iop_chan);
 460         }
 461 }
 462
 463 static dma_cookie_t
 464 iop_adma_tx_submit(struct dma_async_tx_descriptor *tx)
 465 {
 466         struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx);
 467         struct iop_adma_chan *iop_chan = to_iop_adma_chan(tx->chan);
 468         struct iop_adma_desc_slot *grp_start, *old_chain_tail;
 469         int slot_cnt;
 470         int slots_per_op;
 471         dma_cookie_t cookie;
 472         dma_addr_t next_dma;
 473
 474         grp_start = sw_desc->group_head;
 475         slot_cnt = grp_start->slot_cnt;
 476         slots_per_op = grp_start->slots_per_op;
 477
 478         spin_lock_bh(&iop_chan->lock);
 479         cookie = iop_desc_assign_cookie(iop_chan, sw_desc);
 480
 481         old_chain_tail = list_entry(iop_chan->chain.prev,
 482                 struct iop_adma_desc_slot, chain_node);
 483         list_splice_init(&sw_desc->tx_list,
 484                          &old_chain_tail->chain_node);
 485
 486         /* fix up the hardware chain */
 487         next_dma = grp_start->async_tx.phys;
 488         iop_desc_set_next_desc(old_chain_tail, next_dma);
 489         BUG_ON(iop_desc_get_next_desc(old_chain_tail) != next_dma); /* flush */
 490
 491         /* check for pre-chained descriptors */
 492         iop_paranoia(iop_desc_get_next_desc(sw_desc));
 493
 494         /* increment the pending count by the number of slots
 495          * memcpy operations have a 1:1 (slot:operation) relation
 496          * other operations are heavier and will pop the threshold
 497          * more often.
 498          */
 499         iop_chan->pending += slot_cnt;
 500         iop_adma_check_threshold(iop_chan);
 501         spin_unlock_bh(&iop_chan->lock);
 502
 503         dev_dbg(iop_chan->device->common.dev, "%s cookie: %d slot: %d\n",
 504                 __func__, sw_desc->async_tx.cookie, sw_desc->idx);
 505
 506         return cookie;
 507 }
 508
 509 static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan);
 510 static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan);
 511
 512 /**
 513  * iop_adma_alloc_chan_resources -  returns the number of allocated descriptors
 514  * @chan - allocate descriptor resources for this channel
 515  * @client - current client requesting the channel be ready for requests
 516  *
 517  * Note: We keep the slots for 1 operation on iop_chan->chain at all times.  To
 518  * avoid deadlock, via async_xor, num_descs_in_pool must at a minimum be
 519  * greater than 2x the number slots needed to satisfy a device->max_xor
 520  * request.
 521  * */
 522 static int iop_adma_alloc_chan_resources(struct dma_chan *chan)
 523 {
 524         char *hw_desc;
 525         int idx;
 526         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 527         struct iop_adma_desc_slot *slot = NULL;
 528         int init = iop_chan->slots_allocated ? 0 : 1;
 529         struct iop_adma_platform_data *plat_data =
 530                 iop_chan->device->pdev->dev.platform_data;
 531         int num_descs_in_pool = plat_data->pool_size/IOP_ADMA_SLOT_SIZE;
 532
 533         /* Allocate descriptor slots */
 534         do {
 535                 idx = iop_chan->slots_allocated;
 536                 if (idx == num_descs_in_pool)
 537                         break;
 538
 539                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 540                 if (!slot) {
 541                         printk(KERN_INFO "IOP ADMA Channel only initialized"
 542                                 " %d descriptor slots", idx);
 543                         break;
 544                 }
 545                 hw_desc = (char *) iop_chan->device->dma_desc_pool_virt;
 546                 slot->hw_desc = (void *) &hw_desc[idx * IOP_ADMA_SLOT_SIZE];
 547
 548                 dma_async_tx_descriptor_init(&slot->async_tx, chan);
 549                 slot->async_tx.tx_submit = iop_adma_tx_submit;
 550                 INIT_LIST_HEAD(&slot->tx_list);
 551                 INIT_LIST_HEAD(&slot->chain_node);
 552                 INIT_LIST_HEAD(&slot->slot_node);
 553                 hw_desc = (char *) iop_chan->device->dma_desc_pool;
 554                 slot->async_tx.phys =
 555                         (dma_addr_t) &hw_desc[idx * IOP_ADMA_SLOT_SIZE];
 556                 slot->idx = idx;
 557
 558                 spin_lock_bh(&iop_chan->lock);
 559                 iop_chan->slots_allocated++;
 560                 list_add_tail(&slot->slot_node, &iop_chan->all_slots);
 561                 spin_unlock_bh(&iop_chan->lock);
 562         } while (iop_chan->slots_allocated < num_descs_in_pool);
 563
 564         if (idx && !iop_chan->last_used)
 565                 iop_chan->last_used = list_entry(iop_chan->all_slots.next,
 566                                         struct iop_adma_desc_slot,
 567                                         slot_node);
 568
 569         dev_dbg(iop_chan->device->common.dev,
 570                 "allocated %d descriptor slots last_used: %p\n",
 571                 iop_chan->slots_allocated, iop_chan->last_used);
 572
 573         /* initialize the channel and the chain with a null operation */
 574         if (init) {
 575                 if (dma_has_cap(DMA_MEMCPY,
 576                         iop_chan->device->common.cap_mask))
 577                         iop_chan_start_null_memcpy(iop_chan);
 578                 else if (dma_has_cap(DMA_XOR,
 579                         iop_chan->device->common.cap_mask))
 580                         iop_chan_start_null_xor(iop_chan);
 581                 else
 582                         BUG();
 583         }
 584
 585         return (idx > 0) ? idx : -ENOMEM;
 586 }
 587
 588 static struct dma_async_tx_descriptor *
 589 iop_adma_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
 590 {
 591         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 592         struct iop_adma_desc_slot *sw_desc, *grp_start;
 593         int slot_cnt, slots_per_op;
 594
 595         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
 596
 597         spin_lock_bh(&iop_chan->lock);
 598         slot_cnt = iop_chan_interrupt_slot_count(&slots_per_op, iop_chan);
 599         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 600         if (sw_desc) {
 601                 grp_start = sw_desc->group_head;
 602                 iop_desc_init_interrupt(grp_start, iop_chan);
 603                 grp_start->unmap_len = 0;
 604                 sw_desc->async_tx.flags = flags;
 605         }
 606         spin_unlock_bh(&iop_chan->lock);
 607
 608         return sw_desc ? &sw_desc->async_tx : NULL;
 609 }
 610
 611 static struct dma_async_tx_descriptor *
 612 iop_adma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dma_dest,
 613                          dma_addr_t dma_src, size_t len, unsigned long flags)
 614 {
 615         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 616         struct iop_adma_desc_slot *sw_desc, *grp_start;
 617         int slot_cnt, slots_per_op;
 618
 619         if (unlikely(!len))
 620                 return NULL;
 621         BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT));
 622
 623         dev_dbg(iop_chan->device->common.dev, "%s len: %u\n",
 624                 __func__, len);
 625
 626         spin_lock_bh(&iop_chan->lock);
 627         slot_cnt = iop_chan_memcpy_slot_count(len, &slots_per_op);
 628         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 629         if (sw_desc) {
 630                 grp_start = sw_desc->group_head;
 631                 iop_desc_init_memcpy(grp_start, flags);
 632                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 633                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 634                 iop_desc_set_memcpy_src_addr(grp_start, dma_src);
 635                 sw_desc->unmap_src_cnt = 1;
 636                 sw_desc->unmap_len = len;
 637                 sw_desc->async_tx.flags = flags;
 638         }
 639         spin_unlock_bh(&iop_chan->lock);
 640
 641         return sw_desc ? &sw_desc->async_tx : NULL;
 642 }
 643
 644 static struct dma_async_tx_descriptor *
 645 iop_adma_prep_dma_memset(struct dma_chan *chan, dma_addr_t dma_dest,
 646                          int value, size_t len, unsigned long flags)
 647 {
 648         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 649         struct iop_adma_desc_slot *sw_desc, *grp_start;
 650         int slot_cnt, slots_per_op;
 651
 652         if (unlikely(!len))
 653                 return NULL;
 654         BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT));
 655
 656         dev_dbg(iop_chan->device->common.dev, "%s len: %u\n",
 657                 __func__, len);
 658
 659         spin_lock_bh(&iop_chan->lock);
 660         slot_cnt = iop_chan_memset_slot_count(len, &slots_per_op);
 661         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 662         if (sw_desc) {
 663                 grp_start = sw_desc->group_head;
 664                 iop_desc_init_memset(grp_start, flags);
 665                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 666                 iop_desc_set_block_fill_val(grp_start, value);
 667                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 668                 sw_desc->unmap_src_cnt = 1;
 669                 sw_desc->unmap_len = len;
 670                 sw_desc->async_tx.flags = flags;
 671         }
 672         spin_unlock_bh(&iop_chan->lock);
 673
 674         return sw_desc ? &sw_desc->async_tx : NULL;
 675 }
 676
 677 static struct dma_async_tx_descriptor *
 678 iop_adma_prep_dma_xor(struct dma_chan *chan, dma_addr_t dma_dest,
 679                       dma_addr_t *dma_src, unsigned int src_cnt, size_t len,
 680                       unsigned long flags)
 681 {
 682         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 683         struct iop_adma_desc_slot *sw_desc, *grp_start;
 684         int slot_cnt, slots_per_op;
 685
 686         if (unlikely(!len))
 687                 return NULL;
 688         BUG_ON(unlikely(len > IOP_ADMA_XOR_MAX_BYTE_COUNT));
 689
 690         dev_dbg(iop_chan->device->common.dev,
 691                 "%s src_cnt: %d len: %u flags: %lx\n",
 692                 __func__, src_cnt, len, flags);
 693
 694         spin_lock_bh(&iop_chan->lock);
 695         slot_cnt = iop_chan_xor_slot_count(len, src_cnt, &slots_per_op);
 696         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 697         if (sw_desc) {
 698                 grp_start = sw_desc->group_head;
 699                 iop_desc_init_xor(grp_start, src_cnt, flags);
 700                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 701                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 702                 sw_desc->unmap_src_cnt = src_cnt;
 703                 sw_desc->unmap_len = len;
 704                 sw_desc->async_tx.flags = flags;
 705                 while (src_cnt--)
 706                         iop_desc_set_xor_src_addr(grp_start, src_cnt,
 707                                                   dma_src[src_cnt]);
 708         }
 709         spin_unlock_bh(&iop_chan->lock);
 710
 711         return sw_desc ? &sw_desc->async_tx : NULL;
 712 }
 713
 714 static struct dma_async_tx_descriptor *
 715 iop_adma_prep_dma_xor_val(struct dma_chan *chan, dma_addr_t *dma_src,
 716                           unsigned int src_cnt, size_t len, u32 *result,
 717                           unsigned long flags)
 718 {
 719         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 720         struct iop_adma_desc_slot *sw_desc, *grp_start;
 721         int slot_cnt, slots_per_op;
 722
 723         if (unlikely(!len))
 724                 return NULL;
 725
 726         dev_dbg(iop_chan->device->common.dev, "%s src_cnt: %d len: %u\n",
 727                 __func__, src_cnt, len);
 728
 729         spin_lock_bh(&iop_chan->lock);
 730         slot_cnt = iop_chan_zero_sum_slot_count(len, src_cnt, &slots_per_op);
 731         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 732         if (sw_desc) {
 733                 grp_start = sw_desc->group_head;
 734                 iop_desc_init_zero_sum(grp_start, src_cnt, flags);
 735                 iop_desc_set_zero_sum_byte_count(grp_start, len);
 736                 grp_start->xor_check_result = result;
 737                 pr_debug("\t%s: grp_start->xor_check_result: %p\n",
 738                         __func__, grp_start->xor_check_result);
 739                 sw_desc->unmap_src_cnt = src_cnt;
 740                 sw_desc->unmap_len = len;
 741                 sw_desc->async_tx.flags = flags;
 742                 while (src_cnt--)
 743                         iop_desc_set_zero_sum_src_addr(grp_start, src_cnt,
 744                                                        dma_src[src_cnt]);
 745         }
 746         spin_unlock_bh(&iop_chan->lock);
 747
 748         return sw_desc ? &sw_desc->async_tx : NULL;
 749 }
 750
 751 static struct dma_async_tx_descriptor *
 752 iop_adma_prep_dma_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
 753                      unsigned int src_cnt, const unsigned char *scf, size_t len,
 754                      unsigned long flags)
 755 {
 756         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 757         struct iop_adma_desc_slot *sw_desc, *g;
 758         int slot_cnt, slots_per_op;
 759         int continue_srcs;
 760
 761         if (unlikely(!len))
 762                 return NULL;
 763         BUG_ON(len > IOP_ADMA_XOR_MAX_BYTE_COUNT);
 764
 765         dev_dbg(iop_chan->device->common.dev,
 766                 "%s src_cnt: %d len: %u flags: %lx\n",
 767                 __func__, src_cnt, len, flags);
 768
 769         if (dmaf_p_disabled_continue(flags))
 770                 continue_srcs = 1+src_cnt;
 771         else if (dmaf_continue(flags))
 772                 continue_srcs = 3+src_cnt;
 773         else
 774                 continue_srcs = 0+src_cnt;
 775
 776         spin_lock_bh(&iop_chan->lock);
 777         slot_cnt = iop_chan_pq_slot_count(len, continue_srcs, &slots_per_op);
 778         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 779         if (sw_desc) {
 780                 int i;
 781
 782                 g = sw_desc->group_head;
 783                 iop_desc_set_byte_count(g, iop_chan, len);
 784
 785                 /* even if P is disabled its destination address (bits
 786                  * [3:0]) must match Q.  It is ok if P points to an
 787                  * invalid address, it won't be written.
 788                  */
 789                 if (flags & DMA_PREP_PQ_DISABLE_P)
 790                         dst[0] = dst[1] & 0x7;
 791
 792                 iop_desc_set_pq_addr(g, dst);
 793                 sw_desc->unmap_src_cnt = src_cnt;
 794                 sw_desc->unmap_len = len;
 795                 sw_desc->async_tx.flags = flags;
 796                 for (i = 0; i < src_cnt; i++)
 797                         iop_desc_set_pq_src_addr(g, i, src[i], scf[i]);
 798
 799                 /* if we are continuing a previous operation factor in
 800                  * the old p and q values, see the comment for dma_maxpq
 801                  * in include/linux/dmaengine.h
 802                  */
 803                 if (dmaf_p_disabled_continue(flags))
 804                         iop_desc_set_pq_src_addr(g, i++, dst[1], 1);
 805                 else if (dmaf_continue(flags)) {
 806                         iop_desc_set_pq_src_addr(g, i++, dst[0], 0);
 807                         iop_desc_set_pq_src_addr(g, i++, dst[1], 1);
 808                         iop_desc_set_pq_src_addr(g, i++, dst[1], 0);
 809                 }
 810                 iop_desc_init_pq(g, i, flags);
 811         }
 812         spin_unlock_bh(&iop_chan->lock);
 813
 814         return sw_desc ? &sw_desc->async_tx : NULL;
 815 }
 816
 817 static struct dma_async_tx_descriptor *
 818 iop_adma_prep_dma_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
 819                          unsigned int src_cnt, const unsigned char *scf,
 820                          size_t len, enum sum_check_flags *pqres,
 821                          unsigned long flags)
 822 {
 823         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 824         struct iop_adma_desc_slot *sw_desc, *g;
 825         int slot_cnt, slots_per_op;
 826
 827         if (unlikely(!len))
 828                 return NULL;
 829         BUG_ON(len > IOP_ADMA_XOR_MAX_BYTE_COUNT);
 830
 831         dev_dbg(iop_chan->device->common.dev, "%s src_cnt: %d len: %u\n",
 832                 __func__, src_cnt, len);
 833
 834         spin_lock_bh(&iop_chan->lock);
 835         slot_cnt = iop_chan_pq_zero_sum_slot_count(len, src_cnt + 2, &slots_per_op);
 836         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 837         if (sw_desc) {
 838                 /* for validate operations p and q are tagged onto the
 839                  * end of the source list
 840                  */
 841                 int pq_idx = src_cnt;
 842
 843                 g = sw_desc->group_head;
 844                 iop_desc_init_pq_zero_sum(g, src_cnt+2, flags);
 845                 iop_desc_set_pq_zero_sum_byte_count(g, len);
 846                 g->pq_check_result = pqres;
 847                 pr_debug("\t%s: g->pq_check_result: %p\n",
 848                         __func__, g->pq_check_result);
 849                 sw_desc->unmap_src_cnt = src_cnt+2;
 850                 sw_desc->unmap_len = len;
 851                 sw_desc->async_tx.flags = flags;
 852                 while (src_cnt--)
 853                         iop_desc_set_pq_zero_sum_src_addr(g, src_cnt,
 854                                                           src[src_cnt],
 855                                                           scf[src_cnt]);
 856                 iop_desc_set_pq_zero_sum_addr(g, pq_idx, src);
 857         }
 858         spin_unlock_bh(&iop_chan->lock);
 859
 860         return sw_desc ? &sw_desc->async_tx : NULL;
 861 }
 862
 863 static void iop_adma_free_chan_resources(struct dma_chan *chan)
 864 {
 865         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 866         struct iop_adma_desc_slot *iter, *_iter;
 867         int in_use_descs = 0;
 868
 869         iop_adma_slot_cleanup(iop_chan);
 870
 871         spin_lock_bh(&iop_chan->lock);
 872         list_for_each_entry_safe(iter, _iter, &iop_chan->chain,
 873                                         chain_node) {
 874                 in_use_descs++;
 875                 list_del(&iter->chain_node);
 876         }
 877         list_for_each_entry_safe_reverse(
 878                 iter, _iter, &iop_chan->all_slots, slot_node) {
 879                 list_del(&iter->slot_node);
 880                 kfree(iter);
 881                 iop_chan->slots_allocated--;
 882         }
 883         iop_chan->last_used = NULL;
 884
 885         dev_dbg(iop_chan->device->common.dev, "%s slots_allocated %d\n",
 886                 __func__, iop_chan->slots_allocated);
 887         spin_unlock_bh(&iop_chan->lock);
 888
 889         /* one is ok since we left it on there on purpose */
 890         if (in_use_descs > 1)
 891                 printk(KERN_ERR "IOP: Freeing %d in use descriptors!\n",
 892                         in_use_descs - 1);
 893 }
 894
 895 /**
 896  * iop_adma_status - poll the status of an ADMA transaction
 897  * @chan: ADMA channel handle
 898  * @cookie: ADMA transaction identifier
 899  * @txstate: a holder for the current state of the channel or NULL
 900  */
 901 static enum dma_status iop_adma_status(struct dma_chan *chan,
 902                                         dma_cookie_t cookie,
 903                                         struct dma_tx_state *txstate)
 904 {
 905         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 906         dma_cookie_t last_used;
 907         dma_cookie_t last_complete;
 908         enum dma_status ret;
 909
 910         last_used = chan->cookie;
 911         last_complete = iop_chan->completed_cookie;
 912
 913         if (txstate) {
 914                 txstate->last = last_complete;
 915                 txstate->used = last_used;
 916                 txstate->residue = 0;
 917         }
 918
 919         ret = dma_async_is_complete(cookie, last_complete, last_used);
 920         if (ret == DMA_SUCCESS)
 921                 return ret;
 922
 923         iop_adma_slot_cleanup(iop_chan);
 924
 925         last_used = chan->cookie;
 926         last_complete = iop_chan->completed_cookie;
 927
 928         if (txstate) {
 929                 txstate->last = last_complete;
 930                 txstate->used = last_used;
 931                 txstate->residue = 0;
 932         }
 933
 934         return dma_async_is_complete(cookie, last_complete, last_used);
 935 }
 936
 937 static irqreturn_t iop_adma_eot_handler(int irq, void *data)
 938 {
 939         struct iop_adma_chan *chan = data;
 940
 941         dev_dbg(chan->device->common.dev, "%s\n", __func__);
 942
 943         tasklet_schedule(&chan->irq_tasklet);
 944
 945         iop_adma_device_clear_eot_status(chan);
 946
 947         return IRQ_HANDLED;
 948 }
 949
 950 static irqreturn_t iop_adma_eoc_handler(int irq, void *data)
 951 {
 952         struct iop_adma_chan *chan = data;
 953
 954         dev_dbg(chan->device->common.dev, "%s\n", __func__);
 955
 956         tasklet_schedule(&chan->irq_tasklet);
 957
 958         iop_adma_device_clear_eoc_status(chan);
 959
 960         return IRQ_HANDLED;
 961 }
 962
 963 static irqreturn_t iop_adma_err_handler(int irq, void *data)
 964 {
 965         struct iop_adma_chan *chan = data;
 966         unsigned long status = iop_chan_get_status(chan);
 967
 968         dev_printk(KERN_ERR, chan->device->common.dev,
 969                 "error ( %s%s%s%s%s%s%s)\n",
 970                 iop_is_err_int_parity(status, chan) ? "int_parity " : "",
 971                 iop_is_err_mcu_abort(status, chan) ? "mcu_abort " : "",
 972                 iop_is_err_int_tabort(status, chan) ? "int_tabort " : "",
 973                 iop_is_err_int_mabort(status, chan) ? "int_mabort " : "",
 974                 iop_is_err_pci_tabort(status, chan) ? "pci_tabort " : "",
 975                 iop_is_err_pci_mabort(status, chan) ? "pci_mabort " : "",
 976                 iop_is_err_split_tx(status, chan) ? "split_tx " : "");
 977
 978         iop_adma_device_clear_err_status(chan);
 979
 980         BUG();
 981
 982         return IRQ_HANDLED;
 983 }
 984
 985 static void iop_adma_issue_pending(struct dma_chan *chan)
 986 {
 987         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 988
 989         if (iop_chan->pending) {
 990                 iop_chan->pending = 0;
 991                 iop_chan_append(iop_chan);
 992         }
 993 }
 994
 995 /*
 996  * Perform a transaction to verify the HW works.
 997  */
 998 #define IOP_ADMA_TEST_SIZE 2000
 999
1000 static int __devinit iop_adma_memcpy_self_test(struct iop_adma_device *device)
1001 {
1002         int i;
1003         void *src, *dest;
1004         dma_addr_t src_dma, dest_dma;
1005         struct dma_chan *dma_chan;
1006         dma_cookie_t cookie;
1007         struct dma_async_tx_descriptor *tx;
1008         int err = 0;
1009         struct iop_adma_chan *iop_chan;
1010
1011         dev_dbg(device->common.dev, "%s\n", __func__);
1012
1013         src = kmalloc(IOP_ADMA_TEST_SIZE, GFP_KERNEL);
1014         if (!src)
1015                 return -ENOMEM;
1016         dest = kzalloc(IOP_ADMA_TEST_SIZE, GFP_KERNEL);
1017         if (!dest) {
1018                 kfree(src);
1019                 return -ENOMEM;
1020         }
1021
1022         /* Fill in src buffer */
1023         for (i = 0; i < IOP_ADMA_TEST_SIZE; i++)
1024                 ((u8 *) src)[i] = (u8)i;
1025
1026         /* Start copy, using first DMA channel */
1027         dma_chan = container_of(device->common.channels.next,
1028                                 struct dma_chan,
1029                                 device_node);
1030         if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
1031                 err = -ENODEV;
1032                 goto out;
1033         }
1034
1035         dest_dma = dma_map_single(dma_chan->device->dev, dest,
1036                                 IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE);
1037         src_dma = dma_map_single(dma_chan->device->dev, src,
1038                                 IOP_ADMA_TEST_SIZE, DMA_TO_DEVICE);
1039         tx = iop_adma_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
1040                                       IOP_ADMA_TEST_SIZE,
1041                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1042
1043         cookie = iop_adma_tx_submit(tx);
1044         iop_adma_issue_pending(dma_chan);
1045         msleep(1);
1046
1047         if (iop_adma_status(dma_chan, cookie, NULL) !=
1048                         DMA_SUCCESS) {
1049                 dev_printk(KERN_ERR, dma_chan->device->dev,
1050                         "Self-test copy timed out, disabling\n");
1051                 err = -ENODEV;
1052                 goto free_resources;
1053         }
1054
1055         iop_chan = to_iop_adma_chan(dma_chan);
1056         dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma,
1057                 IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE);
1058         if (memcmp(src, dest, IOP_ADMA_TEST_SIZE)) {
1059                 dev_printk(KERN_ERR, dma_chan->device->dev,
1060                         "Self-test copy failed compare, disabling\n");
1061                 err = -ENODEV;
1062                 goto free_resources;
1063         }
1064
1065 free_resources:
1066         iop_adma_free_chan_resources(dma_chan);
1067 out:
1068         kfree(src);
1069         kfree(dest);
1070         return err;
1071 }
1072
1073 #define IOP_ADMA_NUM_SRC_TEST 4 /* must be <= 15 */
1074 static int __devinit
1075 iop_adma_xor_val_self_test(struct iop_adma_device *device)
1076 {
1077         int i, src_idx;
1078         struct page *dest;
1079         struct page *xor_srcs[IOP_ADMA_NUM_SRC_TEST];
1080         struct page *zero_sum_srcs[IOP_ADMA_NUM_SRC_TEST + 1];
1081         dma_addr_t dma_srcs[IOP_ADMA_NUM_SRC_TEST + 1];
1082         dma_addr_t dma_addr, dest_dma;
1083         struct dma_async_tx_descriptor *tx;
1084         struct dma_chan *dma_chan;
1085         dma_cookie_t cookie;
1086         u8 cmp_byte = 0;
1087         u32 cmp_word;
1088         u32 zero_sum_result;
1089         int err = 0;
1090         struct iop_adma_chan *iop_chan;
1091
1092         dev_dbg(device->common.dev, "%s\n", __func__);
1093
1094         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) {
1095                 xor_srcs[src_idx] = alloc_page(GFP_KERNEL);
1096                 if (!xor_srcs[src_idx]) {
1097                         while (src_idx--)
1098                                 __free_page(xor_srcs[src_idx]);
1099                         return -ENOMEM;
1100                 }
1101         }
1102
1103         dest = alloc_page(GFP_KERNEL);
1104         if (!dest) {
1105                 while (src_idx--)
1106                         __free_page(xor_srcs[src_idx]);
1107                 return -ENOMEM;
1108         }
1109
1110         /* Fill in src buffers */
1111         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) {
1112                 u8 *ptr = page_address(xor_srcs[src_idx]);
1113                 for (i = 0; i < PAGE_SIZE; i++)
1114                         ptr[i] = (1 << src_idx);
1115         }
1116
1117         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++)
1118                 cmp_byte ^= (u8) (1 << src_idx);
1119
1120         cmp_word = (cmp_byte << 24) | (cmp_byte << 16) |
1121                         (cmp_byte << 8) | cmp_byte;
1122
1123         memset(page_address(dest), 0, PAGE_SIZE);
1124
1125         dma_chan = container_of(device->common.channels.next,
1126                                 struct dma_chan,
1127                                 device_node);
1128         if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
1129                 err = -ENODEV;
1130                 goto out;
1131         }
1132
1133         /* test xor */
1134         dest_dma = dma_map_page(dma_chan->device->dev, dest, 0,
1135                                 PAGE_SIZE, DMA_FROM_DEVICE);
1136         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++)
1137                 dma_srcs[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
1138                                            0, PAGE_SIZE, DMA_TO_DEVICE);
1139         tx = iop_adma_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
1140                                    IOP_ADMA_NUM_SRC_TEST, PAGE_SIZE,
1141                                    DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1142
1143         cookie = iop_adma_tx_submit(tx);
1144         iop_adma_issue_pending(dma_chan);
1145         msleep(8);
1146
1147         if (iop_adma_status(dma_chan, cookie, NULL) !=
1148                 DMA_SUCCESS) {
1149                 dev_printk(KERN_ERR, dma_chan->device->dev,
1150                         "Self-test xor timed out, disabling\n");
1151                 err = -ENODEV;
1152                 goto free_resources;
1153         }
1154
1155         iop_chan = to_iop_adma_chan(dma_chan);
1156         dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma,
1157                 PAGE_SIZE, DMA_FROM_DEVICE);
1158         for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) {
1159                 u32 *ptr = page_address(dest);
1160                 if (ptr[i] != cmp_word) {
1161                         dev_printk(KERN_ERR, dma_chan->device->dev,
1162                                 "Self-test xor failed compare, disabling\n");
1163                         err = -ENODEV;
1164                         goto free_resources;
1165                 }
1166         }
1167         dma_sync_single_for_device(&iop_chan->device->pdev->dev, dest_dma,
1168                 PAGE_SIZE, DMA_TO_DEVICE);
1169
1170         /* skip zero sum if the capability is not present */
1171         if (!dma_has_cap(DMA_XOR_VAL, dma_chan->device->cap_mask))
1172                 goto free_resources;
1173
1174         /* zero sum the sources with the destintation page */
1175         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++)
1176                 zero_sum_srcs[i] = xor_srcs[i];
1177         zero_sum_srcs[i] = dest;
1178
1179         zero_sum_result = 1;
1180
1181         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++)
1182                 dma_srcs[i] = dma_map_page(dma_chan->device->dev,
1183                                            zero_sum_srcs[i], 0, PAGE_SIZE,
1184                                            DMA_TO_DEVICE);
1185         tx = iop_adma_prep_dma_xor_val(dma_chan, dma_srcs,
1186                                        IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
1187                                        &zero_sum_result,
1188                                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1189
1190         cookie = iop_adma_tx_submit(tx);
1191         iop_adma_issue_pending(dma_chan);
1192         msleep(8);
1193
1194         if (iop_adma_status(dma_chan, cookie, NULL) != DMA_SUCCESS) {
1195                 dev_printk(KERN_ERR, dma_chan->device->dev,
1196                         "Self-test zero sum timed out, disabling\n");
1197                 err = -ENODEV;
1198                 goto free_resources;
1199         }
1200
1201         if (zero_sum_result != 0) {
1202                 dev_printk(KERN_ERR, dma_chan->device->dev,
1203                         "Self-test zero sum failed compare, disabling\n");
1204                 err = -ENODEV;
1205                 goto free_resources;
1206         }
1207
1208         /* test memset */
1209         dma_addr = dma_map_page(dma_chan->device->dev, dest, 0,
1210                         PAGE_SIZE, DMA_FROM_DEVICE);
1211         tx = iop_adma_prep_dma_memset(dma_chan, dma_addr, 0, PAGE_SIZE,
1212                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1213
1214         cookie = iop_adma_tx_submit(tx);
1215         iop_adma_issue_pending(dma_chan);
1216         msleep(8);
1217
1218         if (iop_adma_status(dma_chan, cookie, NULL) != DMA_SUCCESS) {
1219                 dev_printk(KERN_ERR, dma_chan->device->dev,
1220                         "Self-test memset timed out, disabling\n");
1221                 err = -ENODEV;
1222                 goto free_resources;
1223         }
1224
1225         for (i = 0; i < PAGE_SIZE/sizeof(u32); i++) {
1226                 u32 *ptr = page_address(dest);
1227                 if (ptr[i]) {
1228                         dev_printk(KERN_ERR, dma_chan->device->dev,
1229                                 "Self-test memset failed compare, disabling\n");
1230                         err = -ENODEV;
1231                         goto free_resources;
1232                 }
1233         }
1234
1235         /* test for non-zero parity sum */
1236         zero_sum_result = 0;
1237         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++)
1238                 dma_srcs[i] = dma_map_page(dma_chan->device->dev,
1239                                            zero_sum_srcs[i], 0, PAGE_SIZE,
1240                                            DMA_TO_DEVICE);
1241         tx = iop_adma_prep_dma_xor_val(dma_chan, dma_srcs,
1242                                        IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
1243                                        &zero_sum_result,
1244                                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1245
1246         cookie = iop_adma_tx_submit(tx);
1247         iop_adma_issue_pending(dma_chan);
1248         msleep(8);
1249
1250         if (iop_adma_status(dma_chan, cookie, NULL) != DMA_SUCCESS) {
1251                 dev_printk(KERN_ERR, dma_chan->device->dev,
1252                         "Self-test non-zero sum timed out, disabling\n");
1253                 err = -ENODEV;
1254                 goto free_resources;
1255         }
1256
1257         if (zero_sum_result != 1) {
1258                 dev_printk(KERN_ERR, dma_chan->device->dev,
1259                         "Self-test non-zero sum failed compare, disabling\n");
1260                 err = -ENODEV;
1261                 goto free_resources;
1262         }
1263
1264 free_resources:
1265         iop_adma_free_chan_resources(dma_chan);
1266 out:
1267         src_idx = IOP_ADMA_NUM_SRC_TEST;
1268         while (src_idx--)
1269                 __free_page(xor_srcs[src_idx]);
1270         __free_page(dest);
1271         return err;
1272 }
1273
1274 #ifdef CONFIG_MD_RAID6_PQ
1275 static int __devinit
1276 iop_adma_pq_zero_sum_self_test(struct iop_adma_device *device)
1277 {
1278         /* combined sources, software pq results, and extra hw pq results */
1279         struct page *pq[IOP_ADMA_NUM_SRC_TEST+2+2];
1280         /* ptr to the extra hw pq buffers defined above */
1281         struct page **pq_hw = &pq[IOP_ADMA_NUM_SRC_TEST+2];
1282         /* address conversion buffers (dma_map / page_address) */
1283         void *pq_sw[IOP_ADMA_NUM_SRC_TEST+2];
1284         dma_addr_t pq_src[IOP_ADMA_NUM_SRC_TEST];
1285         dma_addr_t pq_dest[2];
1286
1287         int i;
1288         struct dma_async_tx_descriptor *tx;
1289         struct dma_chan *dma_chan;
1290         dma_cookie_t cookie;
1291         u32 zero_sum_result;
1292         int err = 0;
1293         struct device *dev;
1294
1295         dev_dbg(device->common.dev, "%s\n", __func__);
1296
1297         for (i = 0; i < ARRAY_SIZE(pq); i++) {
1298                 pq[i] = alloc_page(GFP_KERNEL);
1299                 if (!pq[i]) {
1300                         while (i--)
1301                                 __free_page(pq[i]);
1302                         return -ENOMEM;
1303                 }
1304         }
1305
1306         /* Fill in src buffers */
1307         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++) {
1308                 pq_sw[i] = page_address(pq[i]);
1309                 memset(pq_sw[i], 0x11111111 * (1<<i), PAGE_SIZE);
1310         }
1311         pq_sw[i] = page_address(pq[i]);
1312         pq_sw[i+1] = page_address(pq[i+1]);
1313
1314         dma_chan = container_of(device->common.channels.next,
1315                                 struct dma_chan,
1316                                 device_node);
1317         if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
1318                 err = -ENODEV;
1319                 goto out;
1320         }
1321
1322         dev = dma_chan->device->dev;
1323
1324         /* initialize the dests */
1325         memset(page_address(pq_hw[0]), 0 , PAGE_SIZE);
1326         memset(page_address(pq_hw[1]), 0 , PAGE_SIZE);
1327
1328         /* test pq */
1329         pq_dest[0] = dma_map_page(dev, pq_hw[0], 0, PAGE_SIZE, DMA_FROM_DEVICE);
1330         pq_dest[1] = dma_map_page(dev, pq_hw[1], 0, PAGE_SIZE, DMA_FROM_DEVICE);
1331         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++)
1332                 pq_src[i] = dma_map_page(dev, pq[i], 0, PAGE_SIZE,
1333                                          DMA_TO_DEVICE);
1334
1335         tx = iop_adma_prep_dma_pq(dma_chan, pq_dest, pq_src,
1336                                   IOP_ADMA_NUM_SRC_TEST, (u8 *)raid6_gfexp,
1337                                   PAGE_SIZE,
1338                                   DMA_PREP_INTERRUPT |
1339                                   DMA_CTRL_ACK);
1340
1341         cookie = iop_adma_tx_submit(tx);
1342         iop_adma_issue_pending(dma_chan);
1343         msleep(8);
1344
1345         if (iop_adma_status(dma_chan, cookie, NULL) !=
1346                 DMA_SUCCESS) {
1347                 dev_err(dev, "Self-test pq timed out, disabling\n");
1348                 err = -ENODEV;
1349                 goto free_resources;
1350         }
1351
1352         raid6_call.gen_syndrome(IOP_ADMA_NUM_SRC_TEST+2, PAGE_SIZE, pq_sw);
1353
1354         if (memcmp(pq_sw[IOP_ADMA_NUM_SRC_TEST],
1355                    page_address(pq_hw[0]), PAGE_SIZE) != 0) {
1356                 dev_err(dev, "Self-test p failed compare, disabling\n");
1357                 err = -ENODEV;
1358                 goto free_resources;
1359         }
1360         if (memcmp(pq_sw[IOP_ADMA_NUM_SRC_TEST+1],
1361                    page_address(pq_hw[1]), PAGE_SIZE) != 0) {
1362                 dev_err(dev, "Self-test q failed compare, disabling\n");
1363                 err = -ENODEV;
1364                 goto free_resources;
1365         }
1366
1367         /* test correct zero sum using the software generated pq values */
1368         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 2; i++)
1369                 pq_src[i] = dma_map_page(dev, pq[i], 0, PAGE_SIZE,
1370                                          DMA_TO_DEVICE);
1371
1372         zero_sum_result = ~0;
1373         tx = iop_adma_prep_dma_pq_val(dma_chan, &pq_src[IOP_ADMA_NUM_SRC_TEST],
1374                                       pq_src, IOP_ADMA_NUM_SRC_TEST,
1375                                       raid6_gfexp, PAGE_SIZE, &zero_sum_result,
1376                                       DMA_PREP_INTERRUPT|DMA_CTRL_ACK);
1377
1378         cookie = iop_adma_tx_submit(tx);
1379         iop_adma_issue_pending(dma_chan);
1380         msleep(8);
1381
1382         if (iop_adma_status(dma_chan, cookie, NULL) !=
1383                 DMA_SUCCESS) {
1384                 dev_err(dev, "Self-test pq-zero-sum timed out, disabling\n");
1385                 err = -ENODEV;
1386                 goto free_resources;
1387         }
1388
1389         if (zero_sum_result != 0) {
1390                 dev_err(dev, "Self-test pq-zero-sum failed to validate: %x\n",
1391                         zero_sum_result);
1392                 err = -ENODEV;
1393                 goto free_resources;
1394         }
1395
1396         /* test incorrect zero sum */
1397         i = IOP_ADMA_NUM_SRC_TEST;
1398         memset(pq_sw[i] + 100, 0, 100);
1399         memset(pq_sw[i+1] + 200, 0, 200);
1400         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 2; i++)
1401                 pq_src[i] = dma_map_page(dev, pq[i], 0, PAGE_SIZE,
1402                                          DMA_TO_DEVICE);
1403
1404         zero_sum_result = 0;
1405         tx = iop_adma_prep_dma_pq_val(dma_chan, &pq_src[IOP_ADMA_NUM_SRC_TEST],
1406                                       pq_src, IOP_ADMA_NUM_SRC_TEST,
1407                                       raid6_gfexp, PAGE_SIZE, &zero_sum_result,
1408                                       DMA_PREP_INTERRUPT|DMA_CTRL_ACK);
1409
1410         cookie = iop_adma_tx_submit(tx);
1411         iop_adma_issue_pending(dma_chan);
1412         msleep(8);
1413
1414         if (iop_adma_status(dma_chan, cookie, NULL) !=
1415                 DMA_SUCCESS) {
1416                 dev_err(dev, "Self-test !pq-zero-sum timed out, disabling\n");
1417                 err = -ENODEV;
1418                 goto free_resources;
1419         }
1420
1421         if (zero_sum_result != (SUM_CHECK_P_RESULT | SUM_CHECK_Q_RESULT)) {
1422                 dev_err(dev, "Self-test !pq-zero-sum failed to validate: %x\n",
1423                         zero_sum_result);
1424                 err = -ENODEV;
1425                 goto free_resources;
1426         }
1427
1428 free_resources:
1429         iop_adma_free_chan_resources(dma_chan);
1430 out:
1431         i = ARRAY_SIZE(pq);
1432         while (i--)
1433                 __free_page(pq[i]);
1434         return err;
1435 }
1436 #endif
1437
1438 static int __devexit iop_adma_remove(struct platform_device *dev)
1439 {
1440         struct iop_adma_device *device = platform_get_drvdata(dev);
1441         struct dma_chan *chan, *_chan;
1442         struct iop_adma_chan *iop_chan;
1443         struct iop_adma_platform_data *plat_data = dev->dev.platform_data;
1444
1445         dma_async_device_unregister(&device->common);
1446
1447         dma_free_coherent(&dev->dev, plat_data->pool_size,
1448                         device->dma_desc_pool_virt, device->dma_desc_pool);
1449
1450         list_for_each_entry_safe(chan, _chan, &device->common.channels,
1451                                 device_node) {
1452                 iop_chan = to_iop_adma_chan(chan);
1453                 list_del(&chan->device_node);
1454                 kfree(iop_chan);
1455         }
1456         kfree(device);
1457
1458         return 0;
1459 }
1460
1461 static int __devinit iop_adma_probe(struct platform_device *pdev)
1462 {
1463         struct resource *res;
1464         int ret = 0, i;
1465         struct iop_adma_device *adev;
1466         struct iop_adma_chan *iop_chan;
1467         struct dma_device *dma_dev;
1468         struct iop_adma_platform_data *plat_data = pdev->dev.platform_data;
1469
1470         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1471         if (!res)
1472                 return -ENODEV;
1473
1474         if (!devm_request_mem_region(&pdev->dev, res->start,
1475                                 resource_size(res), pdev->name))
1476                 return -EBUSY;
1477
1478         adev = kzalloc(sizeof(*adev), GFP_KERNEL);
1479         if (!adev)
1480                 return -ENOMEM;
1481         dma_dev = &adev->common;
1482
1483         /* allocate coherent memory for hardware descriptors
1484          * note: writecombine gives slightly better performance, but
1485          * requires that we explicitly flush the writes
1486          */
1487         if ((adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
1488                                         plat_data->pool_size,
1489                                         &adev->dma_desc_pool,
1490                                         GFP_KERNEL)) == NULL) {
1491                 ret = -ENOMEM;
1492                 goto err_free_adev;
1493         }
1494
1495         dev_dbg(&pdev->dev, "%s: allocted descriptor pool virt %p phys %p\n",
1496                 __func__, adev->dma_desc_pool_virt,
1497                 (void *) adev->dma_desc_pool);
1498
1499         adev->id = plat_data->hw_id;
1500
1501         /* discover transaction capabilites from the platform data */
1502         dma_dev->cap_mask = plat_data->cap_mask;
1503
1504         adev->pdev = pdev;
1505         platform_set_drvdata(pdev, adev);
1506
1507         INIT_LIST_HEAD(&dma_dev->channels);
1508
1509         /* set base routines */
1510         dma_dev->device_alloc_chan_resources = iop_adma_alloc_chan_resources;
1511         dma_dev->device_free_chan_resources = iop_adma_free_chan_resources;
1512         dma_dev->device_tx_status = iop_adma_status;
1513         dma_dev->device_issue_pending = iop_adma_issue_pending;
1514         dma_dev->dev = &pdev->dev;
1515
1516         /* set prep routines based on capability */
1517         if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
1518                 dma_dev->device_prep_dma_memcpy = iop_adma_prep_dma_memcpy;
1519         if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask))
1520                 dma_dev->device_prep_dma_memset = iop_adma_prep_dma_memset;
1521         if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1522                 dma_dev->max_xor = iop_adma_get_max_xor();
1523                 dma_dev->device_prep_dma_xor = iop_adma_prep_dma_xor;
1524         }
1525         if (dma_has_cap(DMA_XOR_VAL, dma_dev->cap_mask))
1526                 dma_dev->device_prep_dma_xor_val =
1527                         iop_adma_prep_dma_xor_val;
1528         if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1529                 dma_set_maxpq(dma_dev, iop_adma_get_max_pq(), 0);
1530                 dma_dev->device_prep_dma_pq = iop_adma_prep_dma_pq;
1531         }
1532         if (dma_has_cap(DMA_PQ_VAL, dma_dev->cap_mask))
1533                 dma_dev->device_prep_dma_pq_val =
1534                         iop_adma_prep_dma_pq_val;
1535         if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
1536                 dma_dev->device_prep_dma_interrupt =
1537                         iop_adma_prep_dma_interrupt;
1538
1539         iop_chan = kzalloc(sizeof(*iop_chan), GFP_KERNEL);
1540         if (!iop_chan) {
1541                 ret = -ENOMEM;
1542                 goto err_free_dma;
1543         }
1544         iop_chan->device = adev;
1545
1546         iop_chan->mmr_base = devm_ioremap(&pdev->dev, res->start,
1547                                         resource_size(res));
1548         if (!iop_chan->mmr_base) {
1549                 ret = -ENOMEM;
1550                 goto err_free_iop_chan;
1551         }
1552         tasklet_init(&iop_chan->irq_tasklet, iop_adma_tasklet, (unsigned long)
1553                 iop_chan);
1554
1555         /* clear errors before enabling interrupts */
1556         iop_adma_device_clear_err_status(iop_chan);
1557
1558         for (i = 0; i < 3; i++) {
1559                 irq_handler_t handler[] = { iop_adma_eot_handler,
1560                                         iop_adma_eoc_handler,
1561                                         iop_adma_err_handler };
1562                 int irq = platform_get_irq(pdev, i);
1563                 if (irq < 0) {
1564                         ret = -ENXIO;
1565                         goto err_free_iop_chan;
1566                 } else {
1567                         ret = devm_request_irq(&pdev->dev, irq,
1568                                         handler[i], 0, pdev->name, iop_chan);
1569                         if (ret)
1570                                 goto err_free_iop_chan;
1571                 }
1572         }
1573
1574         spin_lock_init(&iop_chan->lock);
1575         INIT_LIST_HEAD(&iop_chan->chain);
1576         INIT_LIST_HEAD(&iop_chan->all_slots);
1577         iop_chan->common.device = dma_dev;
1578         list_add_tail(&iop_chan->common.device_node, &dma_dev->channels);
1579
1580         if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
1581                 ret = iop_adma_memcpy_self_test(adev);
1582                 dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret);
1583                 if (ret)
1584                         goto err_free_iop_chan;
1585         }
1586
1587         if (dma_has_cap(DMA_XOR, dma_dev->cap_mask) ||
1588             dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
1589                 ret = iop_adma_xor_val_self_test(adev);
1590                 dev_dbg(&pdev->dev, "xor self test returned %d\n", ret);
1591                 if (ret)
1592                         goto err_free_iop_chan;
1593         }
1594
1595         if (dma_has_cap(DMA_PQ, dma_dev->cap_mask) &&
1596             dma_has_cap(DMA_PQ_VAL, dma_dev->cap_mask)) {
1597                 #ifdef CONFIG_MD_RAID6_PQ
1598                 ret = iop_adma_pq_zero_sum_self_test(adev);
1599                 dev_dbg(&pdev->dev, "pq self test returned %d\n", ret);
1600                 #else
1601                 /* can not test raid6, so do not publish capability */
1602                 dma_cap_clear(DMA_PQ, dma_dev->cap_mask);
1603                 dma_cap_clear(DMA_PQ_VAL, dma_dev->cap_mask);
1604                 ret = 0;
1605                 #endif
1606                 if (ret)
1607                         goto err_free_iop_chan;
1608         }
1609
1610         dev_printk(KERN_INFO, &pdev->dev, "Intel(R) IOP: "
1611           "( %s%s%s%s%s%s%s)\n",
1612           dma_has_cap(DMA_PQ, dma_dev->cap_mask) ? "pq " : "",
1613           dma_has_cap(DMA_PQ_VAL, dma_dev->cap_mask) ? "pq_val " : "",
1614           dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
1615           dma_has_cap(DMA_XOR_VAL, dma_dev->cap_mask) ? "xor_val " : "",
1616           dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)  ? "fill " : "",
1617           dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
1618           dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : "");
1619
1620         dma_async_device_register(dma_dev);
1621         goto out;
1622
1623  err_free_iop_chan:
1624         kfree(iop_chan);
1625  err_free_dma:
1626         dma_free_coherent(&adev->pdev->dev, plat_data->pool_size,
1627                         adev->dma_desc_pool_virt, adev->dma_desc_pool);
1628  err_free_adev:
1629         kfree(adev);
1630  out:
1631         return ret;
1632 }
1633
1634 static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan)
1635 {
1636         struct iop_adma_desc_slot *sw_desc, *grp_start;
1637         dma_cookie_t cookie;
1638         int slot_cnt, slots_per_op;
1639
1640         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
1641
1642         spin_lock_bh(&iop_chan->lock);
1643         slot_cnt = iop_chan_memcpy_slot_count(0, &slots_per_op);
1644         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
1645         if (sw_desc) {
1646                 grp_start = sw_desc->group_head;
1647
1648                 list_splice_init(&sw_desc->tx_list, &iop_chan->chain);
1649                 async_tx_ack(&sw_desc->async_tx);
1650                 iop_desc_init_memcpy(grp_start, 0);
1651                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
1652                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
1653                 iop_desc_set_memcpy_src_addr(grp_start, 0);
1654
1655                 cookie = iop_chan->common.cookie;
1656                 cookie++;
1657                 if (cookie <= 1)
1658                         cookie = 2;
1659
1660                 /* initialize the completed cookie to be less than
1661                  * the most recently used cookie
1662                  */
1663                 iop_chan->completed_cookie = cookie - 1;
1664                 iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
1665
1666                 /* channel should not be busy */
1667                 BUG_ON(iop_chan_is_busy(iop_chan));
1668
1669                 /* clear any prior error-status bits */
1670                 iop_adma_device_clear_err_status(iop_chan);
1671
1672                 /* disable operation */
1673                 iop_chan_disable(iop_chan);
1674
1675                 /* set the descriptor address */
1676                 iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys);
1677
1678                 /* 1/ don't add pre-chained descriptors
1679                  * 2/ dummy read to flush next_desc write
1680                  */
1681                 BUG_ON(iop_desc_get_next_desc(sw_desc));
1682
1683                 /* run the descriptor */
1684                 iop_chan_enable(iop_chan);
1685         } else
1686                 dev_printk(KERN_ERR, iop_chan->device->common.dev,
1687                          "failed to allocate null descriptor\n");
1688         spin_unlock_bh(&iop_chan->lock);
1689 }
1690
1691 static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan)
1692 {
1693         struct iop_adma_desc_slot *sw_desc, *grp_start;
1694         dma_cookie_t cookie;
1695         int slot_cnt, slots_per_op;
1696
1697         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
1698
1699         spin_lock_bh(&iop_chan->lock);
1700         slot_cnt = iop_chan_xor_slot_count(0, 2, &slots_per_op);
1701         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
1702         if (sw_desc) {
1703                 grp_start = sw_desc->group_head;
1704                 list_splice_init(&sw_desc->tx_list, &iop_chan->chain);
1705                 async_tx_ack(&sw_desc->async_tx);
1706                 iop_desc_init_null_xor(grp_start, 2, 0);
1707                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
1708                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
1709                 iop_desc_set_xor_src_addr(grp_start, 0, 0);
1710                 iop_desc_set_xor_src_addr(grp_start, 1, 0);
1711
1712                 cookie = iop_chan->common.cookie;
1713                 cookie++;
1714                 if (cookie <= 1)
1715                         cookie = 2;
1716
1717                 /* initialize the completed cookie to be less than
1718                  * the most recently used cookie
1719                  */
1720                 iop_chan->completed_cookie = cookie - 1;
1721                 iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
1722
1723                 /* channel should not be busy */
1724                 BUG_ON(iop_chan_is_busy(iop_chan));
1725
1726                 /* clear any prior error-status bits */
1727                 iop_adma_device_clear_err_status(iop_chan);
1728
1729                 /* disable operation */
1730                 iop_chan_disable(iop_chan);
1731
1732                 /* set the descriptor address */
1733                 iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys);
1734
1735                 /* 1/ don't add pre-chained descriptors
1736                  * 2/ dummy read to flush next_desc write
1737                  */
1738                 BUG_ON(iop_desc_get_next_desc(sw_desc));
1739
1740                 /* run the descriptor */
1741                 iop_chan_enable(iop_chan);
1742         } else
1743                 dev_printk(KERN_ERR, iop_chan->device->common.dev,
1744                         "failed to allocate null descriptor\n");
1745         spin_unlock_bh(&iop_chan->lock);
1746 }
1747
1748 MODULE_ALIAS("platform:iop-adma");
1749
1750 static struct platform_driver iop_adma_driver = {
1751         .probe          = iop_adma_probe,
1752         .remove         = __devexit_p(iop_adma_remove),
1753         .driver         = {
1754                 .owner  = THIS_MODULE,
1755                 .name   = "iop-adma",
1756         },
1757 };
1758
1759 static int __init iop_adma_init (void)
1760 {
1761         return platform_driver_register(&iop_adma_driver);
1762 }
1763
1764 static void __exit iop_adma_exit (void)
1765 {
1766         platform_driver_unregister(&iop_adma_driver);
1767         return;
1768 }
1769 module_exit(iop_adma_exit);
1770 module_init(iop_adma_init);
1771
1772 MODULE_AUTHOR("Intel Corporation");
1773 MODULE_DESCRIPTION("IOP ADMA Engine Driver");
1774 MODULE_LICENSE("GPL");