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
  35 #include <mach/adma.h>
  36
  37 #define to_iop_adma_chan(chan) container_of(chan, struct iop_adma_chan, common)
  38 #define to_iop_adma_device(dev) \
  39         container_of(dev, struct iop_adma_device, common)
  40 #define tx_to_iop_adma_slot(tx) \
  41         container_of(tx, struct iop_adma_desc_slot, async_tx)
  42
  43 /**
  44  * iop_adma_free_slots - flags descriptor slots for reuse
  45  * @slot: Slot to free
  46  * Caller must hold &iop_chan->lock while calling this function
  47  */
  48 static void iop_adma_free_slots(struct iop_adma_desc_slot *slot)
  49 {
  50         int stride = slot->slots_per_op;
  51
  52         while (stride--) {
  53                 slot->slots_per_op = 0;
  54                 slot = list_entry(slot->slot_node.next,
  55                                 struct iop_adma_desc_slot,
  56                                 slot_node);
  57         }
  58 }
  59
  60 static dma_cookie_t
  61 iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc,
  62         struct iop_adma_chan *iop_chan, dma_cookie_t cookie)
  63 {
  64         BUG_ON(desc->async_tx.cookie < 0);
  65         if (desc->async_tx.cookie > 0) {
  66                 cookie = desc->async_tx.cookie;
  67                 desc->async_tx.cookie = 0;
  68
  69                 /* call the callback (must not sleep or submit new
  70                  * operations to this channel)
  71                  */
  72                 if (desc->async_tx.callback)
  73                         desc->async_tx.callback(
  74                                 desc->async_tx.callback_param);
  75
  76                 /* unmap dma addresses
  77                  * (unmap_single vs unmap_page?)
  78                  */
  79                 if (desc->group_head && desc->unmap_len) {
  80                         struct iop_adma_desc_slot *unmap = desc->group_head;
  81                         struct device *dev =
  82                                 &iop_chan->device->pdev->dev;
  83                         u32 len = unmap->unmap_len;
  84                         enum dma_ctrl_flags flags = desc->async_tx.flags;
  85                         u32 src_cnt;
  86                         dma_addr_t addr;
  87                         dma_addr_t dest;
  88
  89                         src_cnt = unmap->unmap_src_cnt;
  90                         dest = iop_desc_get_dest_addr(unmap, iop_chan);
  91                         if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
  92                                 enum dma_data_direction dir;
  93
  94                                 if (src_cnt > 1) /* is xor? */
  95                                         dir = DMA_BIDIRECTIONAL;
  96                                 else
  97                                         dir = DMA_FROM_DEVICE;
  98
  99                                 dma_unmap_page(dev, dest, len, dir);
 100                         }
 101
 102                         if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
 103                                 while (src_cnt--) {
 104                                         addr = iop_desc_get_src_addr(unmap,
 105                                                                      iop_chan,
 106                                                                      src_cnt);
 107                                         if (addr == dest)
 108                                                 continue;
 109                                         dma_unmap_page(dev, addr, len,
 110                                                        DMA_TO_DEVICE);
 111                                 }
 112                         }
 113                         desc->group_head = NULL;
 114                 }
 115         }
 116
 117         /* run dependent operations */
 118         dma_run_dependencies(&desc->async_tx);
 119
 120         return cookie;
 121 }
 122
 123 static int
 124 iop_adma_clean_slot(struct iop_adma_desc_slot *desc,
 125         struct iop_adma_chan *iop_chan)
 126 {
 127         /* the client is allowed to attach dependent operations
 128          * until 'ack' is set
 129          */
 130         if (!async_tx_test_ack(&desc->async_tx))
 131                 return 0;
 132
 133         /* leave the last descriptor in the chain
 134          * so we can append to it
 135          */
 136         if (desc->chain_node.next == &iop_chan->chain)
 137                 return 1;
 138
 139         dev_dbg(iop_chan->device->common.dev,
 140                 "\tfree slot: %d slots_per_op: %d\n",
 141                 desc->idx, desc->slots_per_op);
 142
 143         list_del(&desc->chain_node);
 144         iop_adma_free_slots(desc);
 145
 146         return 0;
 147 }
 148
 149 static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 150 {
 151         struct iop_adma_desc_slot *iter, *_iter, *grp_start = NULL;
 152         dma_cookie_t cookie = 0;
 153         u32 current_desc = iop_chan_get_current_descriptor(iop_chan);
 154         int busy = iop_chan_is_busy(iop_chan);
 155         int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
 156
 157         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
 158         /* free completed slots from the chain starting with
 159          * the oldest descriptor
 160          */
 161         list_for_each_entry_safe(iter, _iter, &iop_chan->chain,
 162                                         chain_node) {
 163                 pr_debug("\tcookie: %d slot: %d busy: %d "
 164                         "this_desc: %#x next_desc: %#x ack: %d\n",
 165                         iter->async_tx.cookie, iter->idx, busy,
 166                         iter->async_tx.phys, iop_desc_get_next_desc(iter),
 167                         async_tx_test_ack(&iter->async_tx));
 168                 prefetch(_iter);
 169                 prefetch(&_iter->async_tx);
 170
 171                 /* do not advance past the current descriptor loaded into the
 172                  * hardware channel, subsequent descriptors are either in
 173                  * process or have not been submitted
 174                  */
 175                 if (seen_current)
 176                         break;
 177
 178                 /* stop the search if we reach the current descriptor and the
 179                  * channel is busy, or if it appears that the current descriptor
 180                  * needs to be re-read (i.e. has been appended to)
 181                  */
 182                 if (iter->async_tx.phys == current_desc) {
 183                         BUG_ON(seen_current++);
 184                         if (busy || iop_desc_get_next_desc(iter))
 185                                 break;
 186                 }
 187
 188                 /* detect the start of a group transaction */
 189                 if (!slot_cnt && !slots_per_op) {
 190                         slot_cnt = iter->slot_cnt;
 191                         slots_per_op = iter->slots_per_op;
 192                         if (slot_cnt <= slots_per_op) {
 193                                 slot_cnt = 0;
 194                                 slots_per_op = 0;
 195                         }
 196                 }
 197
 198                 if (slot_cnt) {
 199                         pr_debug("\tgroup++\n");
 200                         if (!grp_start)
 201                                 grp_start = iter;
 202                         slot_cnt -= slots_per_op;
 203                 }
 204
 205                 /* all the members of a group are complete */
 206                 if (slots_per_op != 0 && slot_cnt == 0) {
 207                         struct iop_adma_desc_slot *grp_iter, *_grp_iter;
 208                         int end_of_chain = 0;
 209                         pr_debug("\tgroup end\n");
 210
 211                         /* collect the total results */
 212                         if (grp_start->xor_check_result) {
 213                                 u32 zero_sum_result = 0;
 214                                 slot_cnt = grp_start->slot_cnt;
 215                                 grp_iter = grp_start;
 216
 217                                 list_for_each_entry_from(grp_iter,
 218                                         &iop_chan->chain, chain_node) {
 219                                         zero_sum_result |=
 220                                             iop_desc_get_zero_result(grp_iter);
 221                                             pr_debug("\titer%d result: %d\n",
 222                                             grp_iter->idx, zero_sum_result);
 223                                         slot_cnt -= slots_per_op;
 224                                         if (slot_cnt == 0)
 225                                                 break;
 226                                 }
 227                                 pr_debug("\tgrp_start->xor_check_result: %p\n",
 228                                         grp_start->xor_check_result);
 229                                 *grp_start->xor_check_result = zero_sum_result;
 230                         }
 231
 232                         /* clean up the group */
 233                         slot_cnt = grp_start->slot_cnt;
 234                         grp_iter = grp_start;
 235                         list_for_each_entry_safe_from(grp_iter, _grp_iter,
 236                                 &iop_chan->chain, chain_node) {
 237                                 cookie = iop_adma_run_tx_complete_actions(
 238                                         grp_iter, iop_chan, cookie);
 239
 240                                 slot_cnt -= slots_per_op;
 241                                 end_of_chain = iop_adma_clean_slot(grp_iter,
 242                                         iop_chan);
 243
 244                                 if (slot_cnt == 0 || end_of_chain)
 245                                         break;
 246                         }
 247
 248                         /* the group should be complete at this point */
 249                         BUG_ON(slot_cnt);
 250
 251                         slots_per_op = 0;
 252                         grp_start = NULL;
 253                         if (end_of_chain)
 254                                 break;
 255                         else
 256                                 continue;
 257                 } else if (slots_per_op) /* wait for group completion */
 258                         continue;
 259
 260                 /* write back zero sum results (single descriptor case) */
 261                 if (iter->xor_check_result && iter->async_tx.cookie)
 262                         *iter->xor_check_result =
 263                                 iop_desc_get_zero_result(iter);
 264
 265                 cookie = iop_adma_run_tx_complete_actions(
 266                                         iter, iop_chan, cookie);
 267
 268                 if (iop_adma_clean_slot(iter, iop_chan))
 269                         break;
 270         }
 271
 272         if (cookie > 0) {
 273                 iop_chan->completed_cookie = cookie;
 274                 pr_debug("\tcompleted cookie %d\n", cookie);
 275         }
 276 }
 277
 278 static void
 279 iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 280 {
 281         spin_lock_bh(&iop_chan->lock);
 282         __iop_adma_slot_cleanup(iop_chan);
 283         spin_unlock_bh(&iop_chan->lock);
 284 }
 285
 286 static void iop_adma_tasklet(unsigned long data)
 287 {
 288         struct iop_adma_chan *iop_chan = (struct iop_adma_chan *) data;
 289
 290         spin_lock(&iop_chan->lock);
 291         __iop_adma_slot_cleanup(iop_chan);
 292         spin_unlock(&iop_chan->lock);
 293 }
 294
 295 static struct iop_adma_desc_slot *
 296 iop_adma_alloc_slots(struct iop_adma_chan *iop_chan, int num_slots,
 297                         int slots_per_op)
 298 {
 299         struct iop_adma_desc_slot *iter, *_iter, *alloc_start = NULL;
 300         LIST_HEAD(chain);
 301         int slots_found, retry = 0;
 302
 303         /* start search from the last allocated descrtiptor
 304          * if a contiguous allocation can not be found start searching
 305          * from the beginning of the list
 306          */
 307 retry:
 308         slots_found = 0;
 309         if (retry == 0)
 310                 iter = iop_chan->last_used;
 311         else
 312                 iter = list_entry(&iop_chan->all_slots,
 313                         struct iop_adma_desc_slot,
 314                         slot_node);
 315
 316         list_for_each_entry_safe_continue(
 317                 iter, _iter, &iop_chan->all_slots, slot_node) {
 318                 prefetch(_iter);
 319                 prefetch(&_iter->async_tx);
 320                 if (iter->slots_per_op) {
 321                         /* give up after finding the first busy slot
 322                          * on the second pass through the list
 323                          */
 324                         if (retry)
 325                                 break;
 326
 327                         slots_found = 0;
 328                         continue;
 329                 }
 330
 331                 /* start the allocation if the slot is correctly aligned */
 332                 if (!slots_found++) {
 333                         if (iop_desc_is_aligned(iter, slots_per_op))
 334                                 alloc_start = iter;
 335                         else {
 336                                 slots_found = 0;
 337                                 continue;
 338                         }
 339                 }
 340
 341                 if (slots_found == num_slots) {
 342                         struct iop_adma_desc_slot *alloc_tail = NULL;
 343                         struct iop_adma_desc_slot *last_used = NULL;
 344                         iter = alloc_start;
 345                         while (num_slots) {
 346                                 int i;
 347                                 dev_dbg(iop_chan->device->common.dev,
 348                                         "allocated slot: %d "
 349                                         "(desc %p phys: %#x) slots_per_op %d\n",
 350                                         iter->idx, iter->hw_desc,
 351                                         iter->async_tx.phys, slots_per_op);
 352
 353                                 /* pre-ack all but the last descriptor */
 354                                 if (num_slots != slots_per_op)
 355                                         async_tx_ack(&iter->async_tx);
 356
 357                                 list_add_tail(&iter->chain_node, &chain);
 358                                 alloc_tail = iter;
 359                                 iter->async_tx.cookie = 0;
 360                                 iter->slot_cnt = num_slots;
 361                                 iter->xor_check_result = NULL;
 362                                 for (i = 0; i < slots_per_op; i++) {
 363                                         iter->slots_per_op = slots_per_op - i;
 364                                         last_used = iter;
 365                                         iter = list_entry(iter->slot_node.next,
 366                                                 struct iop_adma_desc_slot,
 367                                                 slot_node);
 368                                 }
 369                                 num_slots -= slots_per_op;
 370                         }
 371                         alloc_tail->group_head = alloc_start;
 372                         alloc_tail->async_tx.cookie = -EBUSY;
 373                         list_splice(&chain, &alloc_tail->async_tx.tx_list);
 374                         iop_chan->last_used = last_used;
 375                         iop_desc_clear_next_desc(alloc_start);
 376                         iop_desc_clear_next_desc(alloc_tail);
 377                         return alloc_tail;
 378                 }
 379         }
 380         if (!retry++)
 381                 goto retry;
 382
 383         /* perform direct reclaim if the allocation fails */
 384         __iop_adma_slot_cleanup(iop_chan);
 385
 386         return NULL;
 387 }
 388
 389 static dma_cookie_t
 390 iop_desc_assign_cookie(struct iop_adma_chan *iop_chan,
 391         struct iop_adma_desc_slot *desc)
 392 {
 393         dma_cookie_t cookie = iop_chan->common.cookie;
 394         cookie++;
 395         if (cookie < 0)
 396                 cookie = 1;
 397         iop_chan->common.cookie = desc->async_tx.cookie = cookie;
 398         return cookie;
 399 }
 400
 401 static void iop_adma_check_threshold(struct iop_adma_chan *iop_chan)
 402 {
 403         dev_dbg(iop_chan->device->common.dev, "pending: %d\n",
 404                 iop_chan->pending);
 405
 406         if (iop_chan->pending >= IOP_ADMA_THRESHOLD) {
 407                 iop_chan->pending = 0;
 408                 iop_chan_append(iop_chan);
 409         }
 410 }
 411
 412 static dma_cookie_t
 413 iop_adma_tx_submit(struct dma_async_tx_descriptor *tx)
 414 {
 415         struct iop_adma_desc_slot *sw_desc = tx_to_iop_adma_slot(tx);
 416         struct iop_adma_chan *iop_chan = to_iop_adma_chan(tx->chan);
 417         struct iop_adma_desc_slot *grp_start, *old_chain_tail;
 418         int slot_cnt;
 419         int slots_per_op;
 420         dma_cookie_t cookie;
 421         dma_addr_t next_dma;
 422
 423         grp_start = sw_desc->group_head;
 424         slot_cnt = grp_start->slot_cnt;
 425         slots_per_op = grp_start->slots_per_op;
 426
 427         spin_lock_bh(&iop_chan->lock);
 428         cookie = iop_desc_assign_cookie(iop_chan, sw_desc);
 429
 430         old_chain_tail = list_entry(iop_chan->chain.prev,
 431                 struct iop_adma_desc_slot, chain_node);
 432         list_splice_init(&sw_desc->async_tx.tx_list,
 433                          &old_chain_tail->chain_node);
 434
 435         /* fix up the hardware chain */
 436         next_dma = grp_start->async_tx.phys;
 437         iop_desc_set_next_desc(old_chain_tail, next_dma);
 438         BUG_ON(iop_desc_get_next_desc(old_chain_tail) != next_dma); /* flush */
 439
 440         /* check for pre-chained descriptors */
 441         iop_paranoia(iop_desc_get_next_desc(sw_desc));
 442
 443         /* increment the pending count by the number of slots
 444          * memcpy operations have a 1:1 (slot:operation) relation
 445          * other operations are heavier and will pop the threshold
 446          * more often.
 447          */
 448         iop_chan->pending += slot_cnt;
 449         iop_adma_check_threshold(iop_chan);
 450         spin_unlock_bh(&iop_chan->lock);
 451
 452         dev_dbg(iop_chan->device->common.dev, "%s cookie: %d slot: %d\n",
 453                 __func__, sw_desc->async_tx.cookie, sw_desc->idx);
 454
 455         return cookie;
 456 }
 457
 458 static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan);
 459 static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan);
 460
 461 /**
 462  * iop_adma_alloc_chan_resources -  returns the number of allocated descriptors
 463  * @chan - allocate descriptor resources for this channel
 464  * @client - current client requesting the channel be ready for requests
 465  *
 466  * Note: We keep the slots for 1 operation on iop_chan->chain at all times.  To
 467  * avoid deadlock, via async_xor, num_descs_in_pool must at a minimum be
 468  * greater than 2x the number slots needed to satisfy a device->max_xor
 469  * request.
 470  * */
 471 static int iop_adma_alloc_chan_resources(struct dma_chan *chan)
 472 {
 473         char *hw_desc;
 474         int idx;
 475         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 476         struct iop_adma_desc_slot *slot = NULL;
 477         int init = iop_chan->slots_allocated ? 0 : 1;
 478         struct iop_adma_platform_data *plat_data =
 479                 iop_chan->device->pdev->dev.platform_data;
 480         int num_descs_in_pool = plat_data->pool_size/IOP_ADMA_SLOT_SIZE;
 481
 482         /* Allocate descriptor slots */
 483         do {
 484                 idx = iop_chan->slots_allocated;
 485                 if (idx == num_descs_in_pool)
 486                         break;
 487
 488                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 489                 if (!slot) {
 490                         printk(KERN_INFO "IOP ADMA Channel only initialized"
 491                                 " %d descriptor slots", idx);
 492                         break;
 493                 }
 494                 hw_desc = (char *) iop_chan->device->dma_desc_pool_virt;
 495                 slot->hw_desc = (void *) &hw_desc[idx * IOP_ADMA_SLOT_SIZE];
 496
 497                 dma_async_tx_descriptor_init(&slot->async_tx, chan);
 498                 slot->async_tx.tx_submit = iop_adma_tx_submit;
 499                 INIT_LIST_HEAD(&slot->chain_node);
 500                 INIT_LIST_HEAD(&slot->slot_node);
 501                 INIT_LIST_HEAD(&slot->async_tx.tx_list);
 502                 hw_desc = (char *) iop_chan->device->dma_desc_pool;
 503                 slot->async_tx.phys =
 504                         (dma_addr_t) &hw_desc[idx * IOP_ADMA_SLOT_SIZE];
 505                 slot->idx = idx;
 506
 507                 spin_lock_bh(&iop_chan->lock);
 508                 iop_chan->slots_allocated++;
 509                 list_add_tail(&slot->slot_node, &iop_chan->all_slots);
 510                 spin_unlock_bh(&iop_chan->lock);
 511         } while (iop_chan->slots_allocated < num_descs_in_pool);
 512
 513         if (idx && !iop_chan->last_used)
 514                 iop_chan->last_used = list_entry(iop_chan->all_slots.next,
 515                                         struct iop_adma_desc_slot,
 516                                         slot_node);
 517
 518         dev_dbg(iop_chan->device->common.dev,
 519                 "allocated %d descriptor slots last_used: %p\n",
 520                 iop_chan->slots_allocated, iop_chan->last_used);
 521
 522         /* initialize the channel and the chain with a null operation */
 523         if (init) {
 524                 if (dma_has_cap(DMA_MEMCPY,
 525                         iop_chan->device->common.cap_mask))
 526                         iop_chan_start_null_memcpy(iop_chan);
 527                 else if (dma_has_cap(DMA_XOR,
 528                         iop_chan->device->common.cap_mask))
 529                         iop_chan_start_null_xor(iop_chan);
 530                 else
 531                         BUG();
 532         }
 533
 534         return (idx > 0) ? idx : -ENOMEM;
 535 }
 536
 537 static struct dma_async_tx_descriptor *
 538 iop_adma_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
 539 {
 540         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 541         struct iop_adma_desc_slot *sw_desc, *grp_start;
 542         int slot_cnt, slots_per_op;
 543
 544         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
 545
 546         spin_lock_bh(&iop_chan->lock);
 547         slot_cnt = iop_chan_interrupt_slot_count(&slots_per_op, iop_chan);
 548         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 549         if (sw_desc) {
 550                 grp_start = sw_desc->group_head;
 551                 iop_desc_init_interrupt(grp_start, iop_chan);
 552                 grp_start->unmap_len = 0;
 553                 sw_desc->async_tx.flags = flags;
 554         }
 555         spin_unlock_bh(&iop_chan->lock);
 556
 557         return sw_desc ? &sw_desc->async_tx : NULL;
 558 }
 559
 560 static struct dma_async_tx_descriptor *
 561 iop_adma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dma_dest,
 562                          dma_addr_t dma_src, size_t len, unsigned long flags)
 563 {
 564         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 565         struct iop_adma_desc_slot *sw_desc, *grp_start;
 566         int slot_cnt, slots_per_op;
 567
 568         if (unlikely(!len))
 569                 return NULL;
 570         BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT));
 571
 572         dev_dbg(iop_chan->device->common.dev, "%s len: %u\n",
 573                 __func__, len);
 574
 575         spin_lock_bh(&iop_chan->lock);
 576         slot_cnt = iop_chan_memcpy_slot_count(len, &slots_per_op);
 577         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 578         if (sw_desc) {
 579                 grp_start = sw_desc->group_head;
 580                 iop_desc_init_memcpy(grp_start, flags);
 581                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 582                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 583                 iop_desc_set_memcpy_src_addr(grp_start, dma_src);
 584                 sw_desc->unmap_src_cnt = 1;
 585                 sw_desc->unmap_len = len;
 586                 sw_desc->async_tx.flags = flags;
 587         }
 588         spin_unlock_bh(&iop_chan->lock);
 589
 590         return sw_desc ? &sw_desc->async_tx : NULL;
 591 }
 592
 593 static struct dma_async_tx_descriptor *
 594 iop_adma_prep_dma_memset(struct dma_chan *chan, dma_addr_t dma_dest,
 595                          int value, size_t len, unsigned long flags)
 596 {
 597         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 598         struct iop_adma_desc_slot *sw_desc, *grp_start;
 599         int slot_cnt, slots_per_op;
 600
 601         if (unlikely(!len))
 602                 return NULL;
 603         BUG_ON(unlikely(len > IOP_ADMA_MAX_BYTE_COUNT));
 604
 605         dev_dbg(iop_chan->device->common.dev, "%s len: %u\n",
 606                 __func__, len);
 607
 608         spin_lock_bh(&iop_chan->lock);
 609         slot_cnt = iop_chan_memset_slot_count(len, &slots_per_op);
 610         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 611         if (sw_desc) {
 612                 grp_start = sw_desc->group_head;
 613                 iop_desc_init_memset(grp_start, flags);
 614                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 615                 iop_desc_set_block_fill_val(grp_start, value);
 616                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 617                 sw_desc->unmap_src_cnt = 1;
 618                 sw_desc->unmap_len = len;
 619                 sw_desc->async_tx.flags = flags;
 620         }
 621         spin_unlock_bh(&iop_chan->lock);
 622
 623         return sw_desc ? &sw_desc->async_tx : NULL;
 624 }
 625
 626 static struct dma_async_tx_descriptor *
 627 iop_adma_prep_dma_xor(struct dma_chan *chan, dma_addr_t dma_dest,
 628                       dma_addr_t *dma_src, unsigned int src_cnt, size_t len,
 629                       unsigned long flags)
 630 {
 631         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 632         struct iop_adma_desc_slot *sw_desc, *grp_start;
 633         int slot_cnt, slots_per_op;
 634
 635         if (unlikely(!len))
 636                 return NULL;
 637         BUG_ON(unlikely(len > IOP_ADMA_XOR_MAX_BYTE_COUNT));
 638
 639         dev_dbg(iop_chan->device->common.dev,
 640                 "%s src_cnt: %d len: %u flags: %lx\n",
 641                 __func__, src_cnt, len, flags);
 642
 643         spin_lock_bh(&iop_chan->lock);
 644         slot_cnt = iop_chan_xor_slot_count(len, src_cnt, &slots_per_op);
 645         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 646         if (sw_desc) {
 647                 grp_start = sw_desc->group_head;
 648                 iop_desc_init_xor(grp_start, src_cnt, flags);
 649                 iop_desc_set_byte_count(grp_start, iop_chan, len);
 650                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
 651                 sw_desc->unmap_src_cnt = src_cnt;
 652                 sw_desc->unmap_len = len;
 653                 sw_desc->async_tx.flags = flags;
 654                 while (src_cnt--)
 655                         iop_desc_set_xor_src_addr(grp_start, src_cnt,
 656                                                   dma_src[src_cnt]);
 657         }
 658         spin_unlock_bh(&iop_chan->lock);
 659
 660         return sw_desc ? &sw_desc->async_tx : NULL;
 661 }
 662
 663 static struct dma_async_tx_descriptor *
 664 iop_adma_prep_dma_zero_sum(struct dma_chan *chan, dma_addr_t *dma_src,
 665                            unsigned int src_cnt, size_t len, u32 *result,
 666                            unsigned long flags)
 667 {
 668         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 669         struct iop_adma_desc_slot *sw_desc, *grp_start;
 670         int slot_cnt, slots_per_op;
 671
 672         if (unlikely(!len))
 673                 return NULL;
 674
 675         dev_dbg(iop_chan->device->common.dev, "%s src_cnt: %d len: %u\n",
 676                 __func__, src_cnt, len);
 677
 678         spin_lock_bh(&iop_chan->lock);
 679         slot_cnt = iop_chan_zero_sum_slot_count(len, src_cnt, &slots_per_op);
 680         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
 681         if (sw_desc) {
 682                 grp_start = sw_desc->group_head;
 683                 iop_desc_init_zero_sum(grp_start, src_cnt, flags);
 684                 iop_desc_set_zero_sum_byte_count(grp_start, len);
 685                 grp_start->xor_check_result = result;
 686                 pr_debug("\t%s: grp_start->xor_check_result: %p\n",
 687                         __func__, grp_start->xor_check_result);
 688                 sw_desc->unmap_src_cnt = src_cnt;
 689                 sw_desc->unmap_len = len;
 690                 sw_desc->async_tx.flags = flags;
 691                 while (src_cnt--)
 692                         iop_desc_set_zero_sum_src_addr(grp_start, src_cnt,
 693                                                        dma_src[src_cnt]);
 694         }
 695         spin_unlock_bh(&iop_chan->lock);
 696
 697         return sw_desc ? &sw_desc->async_tx : NULL;
 698 }
 699
 700 static void iop_adma_free_chan_resources(struct dma_chan *chan)
 701 {
 702         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 703         struct iop_adma_desc_slot *iter, *_iter;
 704         int in_use_descs = 0;
 705
 706         iop_adma_slot_cleanup(iop_chan);
 707
 708         spin_lock_bh(&iop_chan->lock);
 709         list_for_each_entry_safe(iter, _iter, &iop_chan->chain,
 710                                         chain_node) {
 711                 in_use_descs++;
 712                 list_del(&iter->chain_node);
 713         }
 714         list_for_each_entry_safe_reverse(
 715                 iter, _iter, &iop_chan->all_slots, slot_node) {
 716                 list_del(&iter->slot_node);
 717                 kfree(iter);
 718                 iop_chan->slots_allocated--;
 719         }
 720         iop_chan->last_used = NULL;
 721
 722         dev_dbg(iop_chan->device->common.dev, "%s slots_allocated %d\n",
 723                 __func__, iop_chan->slots_allocated);
 724         spin_unlock_bh(&iop_chan->lock);
 725
 726         /* one is ok since we left it on there on purpose */
 727         if (in_use_descs > 1)
 728                 printk(KERN_ERR "IOP: Freeing %d in use descriptors!\n",
 729                         in_use_descs - 1);
 730 }
 731
 732 /**
 733  * iop_adma_is_complete - poll the status of an ADMA transaction
 734  * @chan: ADMA channel handle
 735  * @cookie: ADMA transaction identifier
 736  */
 737 static enum dma_status iop_adma_is_complete(struct dma_chan *chan,
 738                                         dma_cookie_t cookie,
 739                                         dma_cookie_t *done,
 740                                         dma_cookie_t *used)
 741 {
 742         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 743         dma_cookie_t last_used;
 744         dma_cookie_t last_complete;
 745         enum dma_status ret;
 746
 747         last_used = chan->cookie;
 748         last_complete = iop_chan->completed_cookie;
 749
 750         if (done)
 751                 *done = last_complete;
 752         if (used)
 753                 *used = last_used;
 754
 755         ret = dma_async_is_complete(cookie, last_complete, last_used);
 756         if (ret == DMA_SUCCESS)
 757                 return ret;
 758
 759         iop_adma_slot_cleanup(iop_chan);
 760
 761         last_used = chan->cookie;
 762         last_complete = iop_chan->completed_cookie;
 763
 764         if (done)
 765                 *done = last_complete;
 766         if (used)
 767                 *used = last_used;
 768
 769         return dma_async_is_complete(cookie, last_complete, last_used);
 770 }
 771
 772 static irqreturn_t iop_adma_eot_handler(int irq, void *data)
 773 {
 774         struct iop_adma_chan *chan = data;
 775
 776         dev_dbg(chan->device->common.dev, "%s\n", __func__);
 777
 778         tasklet_schedule(&chan->irq_tasklet);
 779
 780         iop_adma_device_clear_eot_status(chan);
 781
 782         return IRQ_HANDLED;
 783 }
 784
 785 static irqreturn_t iop_adma_eoc_handler(int irq, void *data)
 786 {
 787         struct iop_adma_chan *chan = data;
 788
 789         dev_dbg(chan->device->common.dev, "%s\n", __func__);
 790
 791         tasklet_schedule(&chan->irq_tasklet);
 792
 793         iop_adma_device_clear_eoc_status(chan);
 794
 795         return IRQ_HANDLED;
 796 }
 797
 798 static irqreturn_t iop_adma_err_handler(int irq, void *data)
 799 {
 800         struct iop_adma_chan *chan = data;
 801         unsigned long status = iop_chan_get_status(chan);
 802
 803         dev_printk(KERN_ERR, chan->device->common.dev,
 804                 "error ( %s%s%s%s%s%s%s)\n",
 805                 iop_is_err_int_parity(status, chan) ? "int_parity " : "",
 806                 iop_is_err_mcu_abort(status, chan) ? "mcu_abort " : "",
 807                 iop_is_err_int_tabort(status, chan) ? "int_tabort " : "",
 808                 iop_is_err_int_mabort(status, chan) ? "int_mabort " : "",
 809                 iop_is_err_pci_tabort(status, chan) ? "pci_tabort " : "",
 810                 iop_is_err_pci_mabort(status, chan) ? "pci_mabort " : "",
 811                 iop_is_err_split_tx(status, chan) ? "split_tx " : "");
 812
 813         iop_adma_device_clear_err_status(chan);
 814
 815         BUG();
 816
 817         return IRQ_HANDLED;
 818 }
 819
 820 static void iop_adma_issue_pending(struct dma_chan *chan)
 821 {
 822         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
 823
 824         if (iop_chan->pending) {
 825                 iop_chan->pending = 0;
 826                 iop_chan_append(iop_chan);
 827         }
 828 }
 829
 830 /*
 831  * Perform a transaction to verify the HW works.
 832  */
 833 #define IOP_ADMA_TEST_SIZE 2000
 834
 835 static int __devinit iop_adma_memcpy_self_test(struct iop_adma_device *device)
 836 {
 837         int i;
 838         void *src, *dest;
 839         dma_addr_t src_dma, dest_dma;
 840         struct dma_chan *dma_chan;
 841         dma_cookie_t cookie;
 842         struct dma_async_tx_descriptor *tx;
 843         int err = 0;
 844         struct iop_adma_chan *iop_chan;
 845
 846         dev_dbg(device->common.dev, "%s\n", __func__);
 847
 848         src = kmalloc(IOP_ADMA_TEST_SIZE, GFP_KERNEL);
 849         if (!src)
 850                 return -ENOMEM;
 851         dest = kzalloc(IOP_ADMA_TEST_SIZE, GFP_KERNEL);
 852         if (!dest) {
 853                 kfree(src);
 854                 return -ENOMEM;
 855         }
 856
 857         /* Fill in src buffer */
 858         for (i = 0; i < IOP_ADMA_TEST_SIZE; i++)
 859                 ((u8 *) src)[i] = (u8)i;
 860
 861         /* Start copy, using first DMA channel */
 862         dma_chan = container_of(device->common.channels.next,
 863                                 struct dma_chan,
 864                                 device_node);
 865         if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
 866                 err = -ENODEV;
 867                 goto out;
 868         }
 869
 870         dest_dma = dma_map_single(dma_chan->device->dev, dest,
 871                                 IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE);
 872         src_dma = dma_map_single(dma_chan->device->dev, src,
 873                                 IOP_ADMA_TEST_SIZE, DMA_TO_DEVICE);
 874         tx = iop_adma_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
 875                                       IOP_ADMA_TEST_SIZE,
 876                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 877
 878         cookie = iop_adma_tx_submit(tx);
 879         iop_adma_issue_pending(dma_chan);
 880         msleep(1);
 881
 882         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) !=
 883                         DMA_SUCCESS) {
 884                 dev_printk(KERN_ERR, dma_chan->device->dev,
 885                         "Self-test copy timed out, disabling\n");
 886                 err = -ENODEV;
 887                 goto free_resources;
 888         }
 889
 890         iop_chan = to_iop_adma_chan(dma_chan);
 891         dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma,
 892                 IOP_ADMA_TEST_SIZE, DMA_FROM_DEVICE);
 893         if (memcmp(src, dest, IOP_ADMA_TEST_SIZE)) {
 894                 dev_printk(KERN_ERR, dma_chan->device->dev,
 895                         "Self-test copy failed compare, disabling\n");
 896                 err = -ENODEV;
 897                 goto free_resources;
 898         }
 899
 900 free_resources:
 901         iop_adma_free_chan_resources(dma_chan);
 902 out:
 903         kfree(src);
 904         kfree(dest);
 905         return err;
 906 }
 907
 908 #define IOP_ADMA_NUM_SRC_TEST 4 /* must be <= 15 */
 909 static int __devinit
 910 iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
 911 {
 912         int i, src_idx;
 913         struct page *dest;
 914         struct page *xor_srcs[IOP_ADMA_NUM_SRC_TEST];
 915         struct page *zero_sum_srcs[IOP_ADMA_NUM_SRC_TEST + 1];
 916         dma_addr_t dma_srcs[IOP_ADMA_NUM_SRC_TEST + 1];
 917         dma_addr_t dma_addr, dest_dma;
 918         struct dma_async_tx_descriptor *tx;
 919         struct dma_chan *dma_chan;
 920         dma_cookie_t cookie;
 921         u8 cmp_byte = 0;
 922         u32 cmp_word;
 923         u32 zero_sum_result;
 924         int err = 0;
 925         struct iop_adma_chan *iop_chan;
 926
 927         dev_dbg(device->common.dev, "%s\n", __func__);
 928
 929         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) {
 930                 xor_srcs[src_idx] = alloc_page(GFP_KERNEL);
 931                 if (!xor_srcs[src_idx])
 932                         while (src_idx--) {
 933                                 __free_page(xor_srcs[src_idx]);
 934                                 return -ENOMEM;
 935                         }
 936         }
 937
 938         dest = alloc_page(GFP_KERNEL);
 939         if (!dest)
 940                 while (src_idx--) {
 941                         __free_page(xor_srcs[src_idx]);
 942                         return -ENOMEM;
 943                 }
 944
 945         /* Fill in src buffers */
 946         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++) {
 947                 u8 *ptr = page_address(xor_srcs[src_idx]);
 948                 for (i = 0; i < PAGE_SIZE; i++)
 949                         ptr[i] = (1 << src_idx);
 950         }
 951
 952         for (src_idx = 0; src_idx < IOP_ADMA_NUM_SRC_TEST; src_idx++)
 953                 cmp_byte ^= (u8) (1 << src_idx);
 954
 955         cmp_word = (cmp_byte << 24) | (cmp_byte << 16) |
 956                         (cmp_byte << 8) | cmp_byte;
 957
 958         memset(page_address(dest), 0, PAGE_SIZE);
 959
 960         dma_chan = container_of(device->common.channels.next,
 961                                 struct dma_chan,
 962                                 device_node);
 963         if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
 964                 err = -ENODEV;
 965                 goto out;
 966         }
 967
 968         /* test xor */
 969         dest_dma = dma_map_page(dma_chan->device->dev, dest, 0,
 970                                 PAGE_SIZE, DMA_FROM_DEVICE);
 971         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++)
 972                 dma_srcs[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
 973                                            0, PAGE_SIZE, DMA_TO_DEVICE);
 974         tx = iop_adma_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
 975                                    IOP_ADMA_NUM_SRC_TEST, PAGE_SIZE,
 976                                    DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 977
 978         cookie = iop_adma_tx_submit(tx);
 979         iop_adma_issue_pending(dma_chan);
 980         msleep(8);
 981
 982         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) !=
 983                 DMA_SUCCESS) {
 984                 dev_printk(KERN_ERR, dma_chan->device->dev,
 985                         "Self-test xor timed out, disabling\n");
 986                 err = -ENODEV;
 987                 goto free_resources;
 988         }
 989
 990         iop_chan = to_iop_adma_chan(dma_chan);
 991         dma_sync_single_for_cpu(&iop_chan->device->pdev->dev, dest_dma,
 992                 PAGE_SIZE, DMA_FROM_DEVICE);
 993         for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) {
 994                 u32 *ptr = page_address(dest);
 995                 if (ptr[i] != cmp_word) {
 996                         dev_printk(KERN_ERR, dma_chan->device->dev,
 997                                 "Self-test xor failed compare, disabling\n");
 998                         err = -ENODEV;
 999                         goto free_resources;
1000                 }
1001         }
1002         dma_sync_single_for_device(&iop_chan->device->pdev->dev, dest_dma,
1003                 PAGE_SIZE, DMA_TO_DEVICE);
1004
1005         /* skip zero sum if the capability is not present */
1006         if (!dma_has_cap(DMA_ZERO_SUM, dma_chan->device->cap_mask))
1007                 goto free_resources;
1008
1009         /* zero sum the sources with the destintation page */
1010         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST; i++)
1011                 zero_sum_srcs[i] = xor_srcs[i];
1012         zero_sum_srcs[i] = dest;
1013
1014         zero_sum_result = 1;
1015
1016         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++)
1017                 dma_srcs[i] = dma_map_page(dma_chan->device->dev,
1018                                            zero_sum_srcs[i], 0, PAGE_SIZE,
1019                                            DMA_TO_DEVICE);
1020         tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
1021                                         IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
1022                                         &zero_sum_result,
1023                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1024
1025         cookie = iop_adma_tx_submit(tx);
1026         iop_adma_issue_pending(dma_chan);
1027         msleep(8);
1028
1029         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
1030                 dev_printk(KERN_ERR, dma_chan->device->dev,
1031                         "Self-test zero sum timed out, disabling\n");
1032                 err = -ENODEV;
1033                 goto free_resources;
1034         }
1035
1036         if (zero_sum_result != 0) {
1037                 dev_printk(KERN_ERR, dma_chan->device->dev,
1038                         "Self-test zero sum failed compare, disabling\n");
1039                 err = -ENODEV;
1040                 goto free_resources;
1041         }
1042
1043         /* test memset */
1044         dma_addr = dma_map_page(dma_chan->device->dev, dest, 0,
1045                         PAGE_SIZE, DMA_FROM_DEVICE);
1046         tx = iop_adma_prep_dma_memset(dma_chan, dma_addr, 0, PAGE_SIZE,
1047                                       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1048
1049         cookie = iop_adma_tx_submit(tx);
1050         iop_adma_issue_pending(dma_chan);
1051         msleep(8);
1052
1053         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
1054                 dev_printk(KERN_ERR, dma_chan->device->dev,
1055                         "Self-test memset timed out, disabling\n");
1056                 err = -ENODEV;
1057                 goto free_resources;
1058         }
1059
1060         for (i = 0; i < PAGE_SIZE/sizeof(u32); i++) {
1061                 u32 *ptr = page_address(dest);
1062                 if (ptr[i]) {
1063                         dev_printk(KERN_ERR, dma_chan->device->dev,
1064                                 "Self-test memset failed compare, disabling\n");
1065                         err = -ENODEV;
1066                         goto free_resources;
1067                 }
1068         }
1069
1070         /* test for non-zero parity sum */
1071         zero_sum_result = 0;
1072         for (i = 0; i < IOP_ADMA_NUM_SRC_TEST + 1; i++)
1073                 dma_srcs[i] = dma_map_page(dma_chan->device->dev,
1074                                            zero_sum_srcs[i], 0, PAGE_SIZE,
1075                                            DMA_TO_DEVICE);
1076         tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
1077                                         IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
1078                                         &zero_sum_result,
1079                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1080
1081         cookie = iop_adma_tx_submit(tx);
1082         iop_adma_issue_pending(dma_chan);
1083         msleep(8);
1084
1085         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
1086                 dev_printk(KERN_ERR, dma_chan->device->dev,
1087                         "Self-test non-zero sum timed out, disabling\n");
1088                 err = -ENODEV;
1089                 goto free_resources;
1090         }
1091
1092         if (zero_sum_result != 1) {
1093                 dev_printk(KERN_ERR, dma_chan->device->dev,
1094                         "Self-test non-zero sum failed compare, disabling\n");
1095                 err = -ENODEV;
1096                 goto free_resources;
1097         }
1098
1099 free_resources:
1100         iop_adma_free_chan_resources(dma_chan);
1101 out:
1102         src_idx = IOP_ADMA_NUM_SRC_TEST;
1103         while (src_idx--)
1104                 __free_page(xor_srcs[src_idx]);
1105         __free_page(dest);
1106         return err;
1107 }
1108
1109 static int __devexit iop_adma_remove(struct platform_device *dev)
1110 {
1111         struct iop_adma_device *device = platform_get_drvdata(dev);
1112         struct dma_chan *chan, *_chan;
1113         struct iop_adma_chan *iop_chan;
1114         struct iop_adma_platform_data *plat_data = dev->dev.platform_data;
1115
1116         dma_async_device_unregister(&device->common);
1117
1118         dma_free_coherent(&dev->dev, plat_data->pool_size,
1119                         device->dma_desc_pool_virt, device->dma_desc_pool);
1120
1121         list_for_each_entry_safe(chan, _chan, &device->common.channels,
1122                                 device_node) {
1123                 iop_chan = to_iop_adma_chan(chan);
1124                 list_del(&chan->device_node);
1125                 kfree(iop_chan);
1126         }
1127         kfree(device);
1128
1129         return 0;
1130 }
1131
1132 static int __devinit iop_adma_probe(struct platform_device *pdev)
1133 {
1134         struct resource *res;
1135         int ret = 0, i;
1136         struct iop_adma_device *adev;
1137         struct iop_adma_chan *iop_chan;
1138         struct dma_device *dma_dev;
1139         struct iop_adma_platform_data *plat_data = pdev->dev.platform_data;
1140
1141         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1142         if (!res)
1143                 return -ENODEV;
1144
1145         if (!devm_request_mem_region(&pdev->dev, res->start,
1146                                 res->end - res->start, pdev->name))
1147                 return -EBUSY;
1148
1149         adev = kzalloc(sizeof(*adev), GFP_KERNEL);
1150         if (!adev)
1151                 return -ENOMEM;
1152         dma_dev = &adev->common;
1153
1154         /* allocate coherent memory for hardware descriptors
1155          * note: writecombine gives slightly better performance, but
1156          * requires that we explicitly flush the writes
1157          */
1158         if ((adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
1159                                         plat_data->pool_size,
1160                                         &adev->dma_desc_pool,
1161                                         GFP_KERNEL)) == NULL) {
1162                 ret = -ENOMEM;
1163                 goto err_free_adev;
1164         }
1165
1166         dev_dbg(&pdev->dev, "%s: allocted descriptor pool virt %p phys %p\n",
1167                 __func__, adev->dma_desc_pool_virt,
1168                 (void *) adev->dma_desc_pool);
1169
1170         adev->id = plat_data->hw_id;
1171
1172         /* discover transaction capabilites from the platform data */
1173         dma_dev->cap_mask = plat_data->cap_mask;
1174
1175         adev->pdev = pdev;
1176         platform_set_drvdata(pdev, adev);
1177
1178         INIT_LIST_HEAD(&dma_dev->channels);
1179
1180         /* set base routines */
1181         dma_dev->device_alloc_chan_resources = iop_adma_alloc_chan_resources;
1182         dma_dev->device_free_chan_resources = iop_adma_free_chan_resources;
1183         dma_dev->device_is_tx_complete = iop_adma_is_complete;
1184         dma_dev->device_issue_pending = iop_adma_issue_pending;
1185         dma_dev->dev = &pdev->dev;
1186
1187         /* set prep routines based on capability */
1188         if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask))
1189                 dma_dev->device_prep_dma_memcpy = iop_adma_prep_dma_memcpy;
1190         if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask))
1191                 dma_dev->device_prep_dma_memset = iop_adma_prep_dma_memset;
1192         if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1193                 dma_dev->max_xor = iop_adma_get_max_xor();
1194                 dma_dev->device_prep_dma_xor = iop_adma_prep_dma_xor;
1195         }
1196         if (dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask))
1197                 dma_dev->device_prep_dma_zero_sum =
1198                         iop_adma_prep_dma_zero_sum;
1199         if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask))
1200                 dma_dev->device_prep_dma_interrupt =
1201                         iop_adma_prep_dma_interrupt;
1202
1203         iop_chan = kzalloc(sizeof(*iop_chan), GFP_KERNEL);
1204         if (!iop_chan) {
1205                 ret = -ENOMEM;
1206                 goto err_free_dma;
1207         }
1208         iop_chan->device = adev;
1209
1210         iop_chan->mmr_base = devm_ioremap(&pdev->dev, res->start,
1211                                         res->end - res->start);
1212         if (!iop_chan->mmr_base) {
1213                 ret = -ENOMEM;
1214                 goto err_free_iop_chan;
1215         }
1216         tasklet_init(&iop_chan->irq_tasklet, iop_adma_tasklet, (unsigned long)
1217                 iop_chan);
1218
1219         /* clear errors before enabling interrupts */
1220         iop_adma_device_clear_err_status(iop_chan);
1221
1222         for (i = 0; i < 3; i++) {
1223                 irq_handler_t handler[] = { iop_adma_eot_handler,
1224                                         iop_adma_eoc_handler,
1225                                         iop_adma_err_handler };
1226                 int irq = platform_get_irq(pdev, i);
1227                 if (irq < 0) {
1228                         ret = -ENXIO;
1229                         goto err_free_iop_chan;
1230                 } else {
1231                         ret = devm_request_irq(&pdev->dev, irq,
1232                                         handler[i], 0, pdev->name, iop_chan);
1233                         if (ret)
1234                                 goto err_free_iop_chan;
1235                 }
1236         }
1237
1238         spin_lock_init(&iop_chan->lock);
1239         INIT_LIST_HEAD(&iop_chan->chain);
1240         INIT_LIST_HEAD(&iop_chan->all_slots);
1241         iop_chan->common.device = dma_dev;
1242         list_add_tail(&iop_chan->common.device_node, &dma_dev->channels);
1243
1244         if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
1245                 ret = iop_adma_memcpy_self_test(adev);
1246                 dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret);
1247                 if (ret)
1248                         goto err_free_iop_chan;
1249         }
1250
1251         if (dma_has_cap(DMA_XOR, dma_dev->cap_mask) ||
1252                 dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
1253                 ret = iop_adma_xor_zero_sum_self_test(adev);
1254                 dev_dbg(&pdev->dev, "xor self test returned %d\n", ret);
1255                 if (ret)
1256                         goto err_free_iop_chan;
1257         }
1258
1259         dev_printk(KERN_INFO, &pdev->dev, "Intel(R) IOP: "
1260           "( %s%s%s%s%s%s%s%s%s%s)\n",
1261           dma_has_cap(DMA_PQ_XOR, dma_dev->cap_mask) ? "pq_xor " : "",
1262           dma_has_cap(DMA_PQ_UPDATE, dma_dev->cap_mask) ? "pq_update " : "",
1263           dma_has_cap(DMA_PQ_ZERO_SUM, dma_dev->cap_mask) ? "pq_zero_sum " : "",
1264           dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "",
1265           dma_has_cap(DMA_DUAL_XOR, dma_dev->cap_mask) ? "dual_xor " : "",
1266           dma_has_cap(DMA_ZERO_SUM, dma_dev->cap_mask) ? "xor_zero_sum " : "",
1267           dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)  ? "fill " : "",
1268           dma_has_cap(DMA_MEMCPY_CRC32C, dma_dev->cap_mask) ? "cpy+crc " : "",
1269           dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "",
1270           dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : "");
1271
1272         dma_async_device_register(dma_dev);
1273         goto out;
1274
1275  err_free_iop_chan:
1276         kfree(iop_chan);
1277  err_free_dma:
1278         dma_free_coherent(&adev->pdev->dev, plat_data->pool_size,
1279                         adev->dma_desc_pool_virt, adev->dma_desc_pool);
1280  err_free_adev:
1281         kfree(adev);
1282  out:
1283         return ret;
1284 }
1285
1286 static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan)
1287 {
1288         struct iop_adma_desc_slot *sw_desc, *grp_start;
1289         dma_cookie_t cookie;
1290         int slot_cnt, slots_per_op;
1291
1292         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
1293
1294         spin_lock_bh(&iop_chan->lock);
1295         slot_cnt = iop_chan_memcpy_slot_count(0, &slots_per_op);
1296         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
1297         if (sw_desc) {
1298                 grp_start = sw_desc->group_head;
1299
1300                 list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain);
1301                 async_tx_ack(&sw_desc->async_tx);
1302                 iop_desc_init_memcpy(grp_start, 0);
1303                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
1304                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
1305                 iop_desc_set_memcpy_src_addr(grp_start, 0);
1306
1307                 cookie = iop_chan->common.cookie;
1308                 cookie++;
1309                 if (cookie <= 1)
1310                         cookie = 2;
1311
1312                 /* initialize the completed cookie to be less than
1313                  * the most recently used cookie
1314                  */
1315                 iop_chan->completed_cookie = cookie - 1;
1316                 iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
1317
1318                 /* channel should not be busy */
1319                 BUG_ON(iop_chan_is_busy(iop_chan));
1320
1321                 /* clear any prior error-status bits */
1322                 iop_adma_device_clear_err_status(iop_chan);
1323
1324                 /* disable operation */
1325                 iop_chan_disable(iop_chan);
1326
1327                 /* set the descriptor address */
1328                 iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys);
1329
1330                 /* 1/ don't add pre-chained descriptors
1331                  * 2/ dummy read to flush next_desc write
1332                  */
1333                 BUG_ON(iop_desc_get_next_desc(sw_desc));
1334
1335                 /* run the descriptor */
1336                 iop_chan_enable(iop_chan);
1337         } else
1338                 dev_printk(KERN_ERR, iop_chan->device->common.dev,
1339                          "failed to allocate null descriptor\n");
1340         spin_unlock_bh(&iop_chan->lock);
1341 }
1342
1343 static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan)
1344 {
1345         struct iop_adma_desc_slot *sw_desc, *grp_start;
1346         dma_cookie_t cookie;
1347         int slot_cnt, slots_per_op;
1348
1349         dev_dbg(iop_chan->device->common.dev, "%s\n", __func__);
1350
1351         spin_lock_bh(&iop_chan->lock);
1352         slot_cnt = iop_chan_xor_slot_count(0, 2, &slots_per_op);
1353         sw_desc = iop_adma_alloc_slots(iop_chan, slot_cnt, slots_per_op);
1354         if (sw_desc) {
1355                 grp_start = sw_desc->group_head;
1356                 list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain);
1357                 async_tx_ack(&sw_desc->async_tx);
1358                 iop_desc_init_null_xor(grp_start, 2, 0);
1359                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
1360                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
1361                 iop_desc_set_xor_src_addr(grp_start, 0, 0);
1362                 iop_desc_set_xor_src_addr(grp_start, 1, 0);
1363
1364                 cookie = iop_chan->common.cookie;
1365                 cookie++;
1366                 if (cookie <= 1)
1367                         cookie = 2;
1368
1369                 /* initialize the completed cookie to be less than
1370                  * the most recently used cookie
1371                  */
1372                 iop_chan->completed_cookie = cookie - 1;
1373                 iop_chan->common.cookie = sw_desc->async_tx.cookie = cookie;
1374
1375                 /* channel should not be busy */
1376                 BUG_ON(iop_chan_is_busy(iop_chan));
1377
1378                 /* clear any prior error-status bits */
1379                 iop_adma_device_clear_err_status(iop_chan);
1380
1381                 /* disable operation */
1382                 iop_chan_disable(iop_chan);
1383
1384                 /* set the descriptor address */
1385                 iop_chan_set_next_descriptor(iop_chan, sw_desc->async_tx.phys);
1386
1387                 /* 1/ don't add pre-chained descriptors
1388                  * 2/ dummy read to flush next_desc write
1389                  */
1390                 BUG_ON(iop_desc_get_next_desc(sw_desc));
1391
1392                 /* run the descriptor */
1393                 iop_chan_enable(iop_chan);
1394         } else
1395                 dev_printk(KERN_ERR, iop_chan->device->common.dev,
1396                         "failed to allocate null descriptor\n");
1397         spin_unlock_bh(&iop_chan->lock);
1398 }
1399
1400 MODULE_ALIAS("platform:iop-adma");
1401
1402 static struct platform_driver iop_adma_driver = {
1403         .probe          = iop_adma_probe,
1404         .remove         = iop_adma_remove,
1405         .driver         = {
1406                 .owner  = THIS_MODULE,
1407                 .name   = "iop-adma",
1408         },
1409 };
1410
1411 static int __init iop_adma_init (void)
1412 {
1413         return platform_driver_register(&iop_adma_driver);
1414 }
1415
1416 static void __exit iop_adma_exit (void)
1417 {
1418         platform_driver_unregister(&iop_adma_driver);
1419         return;
1420 }
1421 module_exit(iop_adma_exit);
1422 module_init(iop_adma_init);
1423
1424 MODULE_AUTHOR("Intel Corporation");
1425 MODULE_DESCRIPTION("IOP ADMA Engine Driver");
1426 MODULE_LICENSE("GPL");