drivers/dma/ioat_dma.c

   1 /*
   2  * Intel I/OAT DMA Linux driver
   3  * Copyright(c) 2004 - 2007 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 that 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  * The full GNU General Public License is included in this distribution in
  19  * the file called "COPYING".
  20  *
  21  */
  22
  23 /*
  24  * This driver supports an Intel I/OAT DMA engine, which does asynchronous
  25  * copy operations.
  26  */
  27
  28 #include <linux/init.h>
  29 #include <linux/module.h>
  30 #include <linux/pci.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/dmaengine.h>
  33 #include <linux/delay.h>
  34 #include <linux/dma-mapping.h>
  35 #include "ioatdma.h"
  36 #include "ioatdma_registers.h"
  37 #include "ioatdma_hw.h"
  38
  39 #define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
  40 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, common)
  41 #define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
  42 #define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
  43
  44 static int ioat_pending_level = 4;
  45 module_param(ioat_pending_level, int, 0644);
  46 MODULE_PARM_DESC(ioat_pending_level,
  47                  "high-water mark for pushing ioat descriptors (default: 4)");
  48
  49 /* internal functions */
  50 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan);
  51 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
  52
  53 static struct ioat_desc_sw *
  54 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
  55 static struct ioat_desc_sw *
  56 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
  57
  58 static inline struct ioat_dma_chan *ioat_lookup_chan_by_index(
  59                                                 struct ioatdma_device *device,
  60                                                 int index)
  61 {
  62         return device->idx[index];
  63 }
  64
  65 /**
  66  * ioat_dma_do_interrupt - handler used for single vector interrupt mode
  67  * @irq: interrupt id
  68  * @data: interrupt data
  69  */
  70 static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
  71 {
  72         struct ioatdma_device *instance = data;
  73         struct ioat_dma_chan *ioat_chan;
  74         unsigned long attnstatus;
  75         int bit;
  76         u8 intrctrl;
  77
  78         intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
  79
  80         if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
  81                 return IRQ_NONE;
  82
  83         if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
  84                 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
  85                 return IRQ_NONE;
  86         }
  87
  88         attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
  89         for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
  90                 ioat_chan = ioat_lookup_chan_by_index(instance, bit);
  91                 tasklet_schedule(&ioat_chan->cleanup_task);
  92         }
  93
  94         writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
  95         return IRQ_HANDLED;
  96 }
  97
  98 /**
  99  * ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
 100  * @irq: interrupt id
 101  * @data: interrupt data
 102  */
 103 static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
 104 {
 105         struct ioat_dma_chan *ioat_chan = data;
 106
 107         tasklet_schedule(&ioat_chan->cleanup_task);
 108
 109         return IRQ_HANDLED;
 110 }
 111
 112 static void ioat_dma_cleanup_tasklet(unsigned long data);
 113
 114 /**
 115  * ioat_dma_enumerate_channels - find and initialize the device's channels
 116  * @device: the device to be enumerated
 117  */
 118 static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
 119 {
 120         u8 xfercap_scale;
 121         u32 xfercap;
 122         int i;
 123         struct ioat_dma_chan *ioat_chan;
 124
 125         device->common.chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
 126         xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
 127         xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
 128
 129         for (i = 0; i < device->common.chancnt; i++) {
 130                 ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
 131                 if (!ioat_chan) {
 132                         device->common.chancnt = i;
 133                         break;
 134                 }
 135
 136                 ioat_chan->device = device;
 137                 ioat_chan->reg_base = device->reg_base + (0x80 * (i + 1));
 138                 ioat_chan->xfercap = xfercap;
 139                 ioat_chan->desccount = 0;
 140                 if (ioat_chan->device->version != IOAT_VER_1_2) {
 141                         writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE
 142                                         | IOAT_DMA_DCA_ANY_CPU,
 143                                 ioat_chan->reg_base + IOAT_DCACTRL_OFFSET);
 144                 }
 145                 spin_lock_init(&ioat_chan->cleanup_lock);
 146                 spin_lock_init(&ioat_chan->desc_lock);
 147                 INIT_LIST_HEAD(&ioat_chan->free_desc);
 148                 INIT_LIST_HEAD(&ioat_chan->used_desc);
 149                 /* This should be made common somewhere in dmaengine.c */
 150                 ioat_chan->common.device = &device->common;
 151                 list_add_tail(&ioat_chan->common.device_node,
 152                               &device->common.channels);
 153                 device->idx[i] = ioat_chan;
 154                 tasklet_init(&ioat_chan->cleanup_task,
 155                              ioat_dma_cleanup_tasklet,
 156                              (unsigned long) ioat_chan);
 157                 tasklet_disable(&ioat_chan->cleanup_task);
 158         }
 159         return device->common.chancnt;
 160 }
 161
 162 /**
 163  * ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
 164  *                                 descriptors to hw
 165  * @chan: DMA channel handle
 166  */
 167 static inline void __ioat1_dma_memcpy_issue_pending(
 168                                                 struct ioat_dma_chan *ioat_chan)
 169 {
 170         ioat_chan->pending = 0;
 171         writeb(IOAT_CHANCMD_APPEND, ioat_chan->reg_base + IOAT1_CHANCMD_OFFSET);
 172 }
 173
 174 static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
 175 {
 176         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 177
 178         if (ioat_chan->pending != 0) {
 179                 spin_lock_bh(&ioat_chan->desc_lock);
 180                 __ioat1_dma_memcpy_issue_pending(ioat_chan);
 181                 spin_unlock_bh(&ioat_chan->desc_lock);
 182         }
 183 }
 184
 185 static inline void __ioat2_dma_memcpy_issue_pending(
 186                                                 struct ioat_dma_chan *ioat_chan)
 187 {
 188         ioat_chan->pending = 0;
 189         writew(ioat_chan->dmacount,
 190                ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
 191 }
 192
 193 static void ioat2_dma_memcpy_issue_pending(struct dma_chan *chan)
 194 {
 195         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 196
 197         if (ioat_chan->pending != 0) {
 198                 spin_lock_bh(&ioat_chan->desc_lock);
 199                 __ioat2_dma_memcpy_issue_pending(ioat_chan);
 200                 spin_unlock_bh(&ioat_chan->desc_lock);
 201         }
 202 }
 203
 204 static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
 205 {
 206         struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
 207         struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
 208         struct ioat_desc_sw *prev, *new;
 209         struct ioat_dma_descriptor *hw;
 210         dma_cookie_t cookie;
 211         LIST_HEAD(new_chain);
 212         u32 copy;
 213         size_t len;
 214         dma_addr_t src, dst;
 215         int orig_ack;
 216         unsigned int desc_count = 0;
 217
 218         /* src and dest and len are stored in the initial descriptor */
 219         len = first->len;
 220         src = first->src;
 221         dst = first->dst;
 222         orig_ack = first->async_tx.ack;
 223         new = first;
 224
 225         spin_lock_bh(&ioat_chan->desc_lock);
 226         prev = to_ioat_desc(ioat_chan->used_desc.prev);
 227         prefetch(prev->hw);
 228         do {
 229                 copy = min_t(size_t, len, ioat_chan->xfercap);
 230
 231                 new->async_tx.ack = 1;
 232
 233                 hw = new->hw;
 234                 hw->size = copy;
 235                 hw->ctl = 0;
 236                 hw->src_addr = src;
 237                 hw->dst_addr = dst;
 238                 hw->next = 0;
 239
 240                 /* chain together the physical address list for the HW */
 241                 wmb();
 242                 prev->hw->next = (u64) new->async_tx.phys;
 243
 244                 len -= copy;
 245                 dst += copy;
 246                 src += copy;
 247
 248                 list_add_tail(&new->node, &new_chain);
 249                 desc_count++;
 250                 prev = new;
 251         } while (len && (new = ioat1_dma_get_next_descriptor(ioat_chan)));
 252
 253         hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
 254         if (new->async_tx.callback) {
 255                 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
 256                 if (first != new) {
 257                         /* move callback into to last desc */
 258                         new->async_tx.callback = first->async_tx.callback;
 259                         new->async_tx.callback_param
 260                                         = first->async_tx.callback_param;
 261                         first->async_tx.callback = NULL;
 262                         first->async_tx.callback_param = NULL;
 263                 }
 264         }
 265
 266         new->tx_cnt = desc_count;
 267         new->async_tx.ack = orig_ack; /* client is in control of this ack */
 268
 269         /* store the original values for use in later cleanup */
 270         if (new != first) {
 271                 new->src = first->src;
 272                 new->dst = first->dst;
 273                 new->len = first->len;
 274         }
 275
 276         /* cookie incr and addition to used_list must be atomic */
 277         cookie = ioat_chan->common.cookie;
 278         cookie++;
 279         if (cookie < 0)
 280                 cookie = 1;
 281         ioat_chan->common.cookie = new->async_tx.cookie = cookie;
 282
 283         /* write address into NextDescriptor field of last desc in chain */
 284         to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
 285                                                         first->async_tx.phys;
 286         __list_splice(&new_chain, ioat_chan->used_desc.prev);
 287
 288         ioat_chan->dmacount += desc_count;
 289         ioat_chan->pending += desc_count;
 290         if (ioat_chan->pending >= ioat_pending_level)
 291                 __ioat1_dma_memcpy_issue_pending(ioat_chan);
 292         spin_unlock_bh(&ioat_chan->desc_lock);
 293
 294         return cookie;
 295 }
 296
 297 static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
 298 {
 299         struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
 300         struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
 301         struct ioat_desc_sw *new;
 302         struct ioat_dma_descriptor *hw;
 303         dma_cookie_t cookie;
 304         u32 copy;
 305         size_t len;
 306         dma_addr_t src, dst;
 307         int orig_ack;
 308         unsigned int desc_count = 0;
 309
 310         /* src and dest and len are stored in the initial descriptor */
 311         len = first->len;
 312         src = first->src;
 313         dst = first->dst;
 314         orig_ack = first->async_tx.ack;
 315         new = first;
 316
 317         /*
 318          * ioat_chan->desc_lock is still in force in version 2 path
 319          * it gets unlocked at end of this function
 320          */
 321         do {
 322                 copy = min_t(size_t, len, ioat_chan->xfercap);
 323
 324                 new->async_tx.ack = 1;
 325
 326                 hw = new->hw;
 327                 hw->size = copy;
 328                 hw->ctl = 0;
 329                 hw->src_addr = src;
 330                 hw->dst_addr = dst;
 331
 332                 len -= copy;
 333                 dst += copy;
 334                 src += copy;
 335                 desc_count++;
 336         } while (len && (new = ioat2_dma_get_next_descriptor(ioat_chan)));
 337
 338         hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
 339         if (new->async_tx.callback) {
 340                 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
 341                 if (first != new) {
 342                         /* move callback into to last desc */
 343                         new->async_tx.callback = first->async_tx.callback;
 344                         new->async_tx.callback_param
 345                                         = first->async_tx.callback_param;
 346                         first->async_tx.callback = NULL;
 347                         first->async_tx.callback_param = NULL;
 348                 }
 349         }
 350
 351         new->tx_cnt = desc_count;
 352         new->async_tx.ack = orig_ack; /* client is in control of this ack */
 353
 354         /* store the original values for use in later cleanup */
 355         if (new != first) {
 356                 new->src = first->src;
 357                 new->dst = first->dst;
 358                 new->len = first->len;
 359         }
 360
 361         /* cookie incr and addition to used_list must be atomic */
 362         cookie = ioat_chan->common.cookie;
 363         cookie++;
 364         if (cookie < 0)
 365                 cookie = 1;
 366         ioat_chan->common.cookie = new->async_tx.cookie = cookie;
 367
 368         ioat_chan->dmacount += desc_count;
 369         ioat_chan->pending += desc_count;
 370         if (ioat_chan->pending >= ioat_pending_level)
 371                 __ioat2_dma_memcpy_issue_pending(ioat_chan);
 372         spin_unlock_bh(&ioat_chan->desc_lock);
 373
 374         return cookie;
 375 }
 376
 377 /**
 378  * ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
 379  * @ioat_chan: the channel supplying the memory pool for the descriptors
 380  * @flags: allocation flags
 381  */
 382 static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
 383                                         struct ioat_dma_chan *ioat_chan,
 384                                         gfp_t flags)
 385 {
 386         struct ioat_dma_descriptor *desc;
 387         struct ioat_desc_sw *desc_sw;
 388         struct ioatdma_device *ioatdma_device;
 389         dma_addr_t phys;
 390
 391         ioatdma_device = to_ioatdma_device(ioat_chan->common.device);
 392         desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
 393         if (unlikely(!desc))
 394                 return NULL;
 395
 396         desc_sw = kzalloc(sizeof(*desc_sw), flags);
 397         if (unlikely(!desc_sw)) {
 398                 pci_pool_free(ioatdma_device->dma_pool, desc, phys);
 399                 return NULL;
 400         }
 401
 402         memset(desc, 0, sizeof(*desc));
 403         dma_async_tx_descriptor_init(&desc_sw->async_tx, &ioat_chan->common);
 404         switch (ioat_chan->device->version) {
 405         case IOAT_VER_1_2:
 406                 desc_sw->async_tx.tx_submit = ioat1_tx_submit;
 407                 break;
 408         case IOAT_VER_2_0:
 409                 desc_sw->async_tx.tx_submit = ioat2_tx_submit;
 410                 break;
 411         }
 412         INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
 413
 414         desc_sw->hw = desc;
 415         desc_sw->async_tx.phys = phys;
 416
 417         return desc_sw;
 418 }
 419
 420 static int ioat_initial_desc_count = 256;
 421 module_param(ioat_initial_desc_count, int, 0644);
 422 MODULE_PARM_DESC(ioat_initial_desc_count,
 423                  "initial descriptors per channel (default: 256)");
 424
 425 /**
 426  * ioat2_dma_massage_chan_desc - link the descriptors into a circle
 427  * @ioat_chan: the channel to be massaged
 428  */
 429 static void ioat2_dma_massage_chan_desc(struct ioat_dma_chan *ioat_chan)
 430 {
 431         struct ioat_desc_sw *desc, *_desc;
 432
 433         /* setup used_desc */
 434         ioat_chan->used_desc.next = ioat_chan->free_desc.next;
 435         ioat_chan->used_desc.prev = NULL;
 436
 437         /* pull free_desc out of the circle so that every node is a hw
 438          * descriptor, but leave it pointing to the list
 439          */
 440         ioat_chan->free_desc.prev->next = ioat_chan->free_desc.next;
 441         ioat_chan->free_desc.next->prev = ioat_chan->free_desc.prev;
 442
 443         /* circle link the hw descriptors */
 444         desc = to_ioat_desc(ioat_chan->free_desc.next);
 445         desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
 446         list_for_each_entry_safe(desc, _desc, ioat_chan->free_desc.next, node) {
 447                 desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
 448         }
 449 }
 450
 451 /**
 452  * ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
 453  * @chan: the channel to be filled out
 454  */
 455 static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
 456 {
 457         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 458         struct ioat_desc_sw *desc;
 459         u16 chanctrl;
 460         u32 chanerr;
 461         int i;
 462         LIST_HEAD(tmp_list);
 463
 464         /* have we already been set up? */
 465         if (!list_empty(&ioat_chan->free_desc))
 466                 return ioat_chan->desccount;
 467
 468         /* Setup register to interrupt and write completion status on error */
 469         chanctrl = IOAT_CHANCTRL_ERR_INT_EN |
 470                 IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
 471                 IOAT_CHANCTRL_ERR_COMPLETION_EN;
 472         writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
 473
 474         chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
 475         if (chanerr) {
 476                 dev_err(&ioat_chan->device->pdev->dev,
 477                         "CHANERR = %x, clearing\n", chanerr);
 478                 writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
 479         }
 480
 481         /* Allocate descriptors */
 482         for (i = 0; i < ioat_initial_desc_count; i++) {
 483                 desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
 484                 if (!desc) {
 485                         dev_err(&ioat_chan->device->pdev->dev,
 486                                 "Only %d initial descriptors\n", i);
 487                         break;
 488                 }
 489                 list_add_tail(&desc->node, &tmp_list);
 490         }
 491         spin_lock_bh(&ioat_chan->desc_lock);
 492         ioat_chan->desccount = i;
 493         list_splice(&tmp_list, &ioat_chan->free_desc);
 494         if (ioat_chan->device->version != IOAT_VER_1_2)
 495                 ioat2_dma_massage_chan_desc(ioat_chan);
 496         spin_unlock_bh(&ioat_chan->desc_lock);
 497
 498         /* allocate a completion writeback area */
 499         /* doing 2 32bit writes to mmio since 1 64b write doesn't work */
 500         ioat_chan->completion_virt =
 501                 pci_pool_alloc(ioat_chan->device->completion_pool,
 502                                GFP_KERNEL,
 503                                &ioat_chan->completion_addr);
 504         memset(ioat_chan->completion_virt, 0,
 505                sizeof(*ioat_chan->completion_virt));
 506         writel(((u64) ioat_chan->completion_addr) & 0x00000000FFFFFFFF,
 507                ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
 508         writel(((u64) ioat_chan->completion_addr) >> 32,
 509                ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
 510
 511         tasklet_enable(&ioat_chan->cleanup_task);
 512         ioat_dma_start_null_desc(ioat_chan);  /* give chain to dma device */
 513         return ioat_chan->desccount;
 514 }
 515
 516 /**
 517  * ioat_dma_free_chan_resources - release all the descriptors
 518  * @chan: the channel to be cleaned
 519  */
 520 static void ioat_dma_free_chan_resources(struct dma_chan *chan)
 521 {
 522         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 523         struct ioatdma_device *ioatdma_device = to_ioatdma_device(chan->device);
 524         struct ioat_desc_sw *desc, *_desc;
 525         int in_use_descs = 0;
 526
 527         tasklet_disable(&ioat_chan->cleanup_task);
 528         ioat_dma_memcpy_cleanup(ioat_chan);
 529
 530         /* Delay 100ms after reset to allow internal DMA logic to quiesce
 531          * before removing DMA descriptor resources.
 532          */
 533         writeb(IOAT_CHANCMD_RESET,
 534                ioat_chan->reg_base
 535                         + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
 536         mdelay(100);
 537
 538         spin_lock_bh(&ioat_chan->desc_lock);
 539         switch (ioat_chan->device->version) {
 540         case IOAT_VER_1_2:
 541                 list_for_each_entry_safe(desc, _desc,
 542                                          &ioat_chan->used_desc, node) {
 543                         in_use_descs++;
 544                         list_del(&desc->node);
 545                         pci_pool_free(ioatdma_device->dma_pool, desc->hw,
 546                                       desc->async_tx.phys);
 547                         kfree(desc);
 548                 }
 549                 list_for_each_entry_safe(desc, _desc,
 550                                          &ioat_chan->free_desc, node) {
 551                         list_del(&desc->node);
 552                         pci_pool_free(ioatdma_device->dma_pool, desc->hw,
 553                                       desc->async_tx.phys);
 554                         kfree(desc);
 555                 }
 556                 break;
 557         case IOAT_VER_2_0:
 558                 list_for_each_entry_safe(desc, _desc,
 559                                          ioat_chan->free_desc.next, node) {
 560                         list_del(&desc->node);
 561                         pci_pool_free(ioatdma_device->dma_pool, desc->hw,
 562                                       desc->async_tx.phys);
 563                         kfree(desc);
 564                 }
 565                 desc = to_ioat_desc(ioat_chan->free_desc.next);
 566                 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
 567                               desc->async_tx.phys);
 568                 kfree(desc);
 569                 INIT_LIST_HEAD(&ioat_chan->free_desc);
 570                 INIT_LIST_HEAD(&ioat_chan->used_desc);
 571                 break;
 572         }
 573         spin_unlock_bh(&ioat_chan->desc_lock);
 574
 575         pci_pool_free(ioatdma_device->completion_pool,
 576                       ioat_chan->completion_virt,
 577                       ioat_chan->completion_addr);
 578
 579         /* one is ok since we left it on there on purpose */
 580         if (in_use_descs > 1)
 581                 dev_err(&ioat_chan->device->pdev->dev,
 582                         "Freeing %d in use descriptors!\n",
 583                         in_use_descs - 1);
 584
 585         ioat_chan->last_completion = ioat_chan->completion_addr = 0;
 586         ioat_chan->pending = 0;
 587         ioat_chan->dmacount = 0;
 588 }
 589
 590 /**
 591  * ioat_dma_get_next_descriptor - return the next available descriptor
 592  * @ioat_chan: IOAT DMA channel handle
 593  *
 594  * Gets the next descriptor from the chain, and must be called with the
 595  * channel's desc_lock held.  Allocates more descriptors if the channel
 596  * has run out.
 597  */
 598 static struct ioat_desc_sw *
 599 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
 600 {
 601         struct ioat_desc_sw *new;
 602
 603         if (!list_empty(&ioat_chan->free_desc)) {
 604                 new = to_ioat_desc(ioat_chan->free_desc.next);
 605                 list_del(&new->node);
 606         } else {
 607                 /* try to get another desc */
 608                 new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
 609                 if (!new) {
 610                         dev_err(&ioat_chan->device->pdev->dev,
 611                                 "alloc failed\n");
 612                         return NULL;
 613                 }
 614         }
 615
 616         prefetch(new->hw);
 617         return new;
 618 }
 619
 620 static struct ioat_desc_sw *
 621 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
 622 {
 623         struct ioat_desc_sw *new;
 624
 625         /*
 626          * used.prev points to where to start processing
 627          * used.next points to next free descriptor
 628          * if used.prev == NULL, there are none waiting to be processed
 629          * if used.next == used.prev.prev, there is only one free descriptor,
 630          *      and we need to use it to as a noop descriptor before
 631          *      linking in a new set of descriptors, since the device
 632          *      has probably already read the pointer to it
 633          */
 634         if (ioat_chan->used_desc.prev &&
 635             ioat_chan->used_desc.next == ioat_chan->used_desc.prev->prev) {
 636
 637                 struct ioat_desc_sw *desc;
 638                 struct ioat_desc_sw *noop_desc;
 639                 int i;
 640
 641                 /* set up the noop descriptor */
 642                 noop_desc = to_ioat_desc(ioat_chan->used_desc.next);
 643                 noop_desc->hw->size = 0;
 644                 noop_desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
 645                 noop_desc->hw->src_addr = 0;
 646                 noop_desc->hw->dst_addr = 0;
 647
 648                 ioat_chan->used_desc.next = ioat_chan->used_desc.next->next;
 649                 ioat_chan->pending++;
 650                 ioat_chan->dmacount++;
 651
 652                 /* try to get a few more descriptors */
 653                 for (i = 16; i; i--) {
 654                         desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
 655                         if (!desc) {
 656                                 dev_err(&ioat_chan->device->pdev->dev,
 657                                         "alloc failed\n");
 658                                 break;
 659                         }
 660                         list_add_tail(&desc->node, ioat_chan->used_desc.next);
 661
 662                         desc->hw->next
 663                                 = to_ioat_desc(desc->node.next)->async_tx.phys;
 664                         to_ioat_desc(desc->node.prev)->hw->next
 665                                 = desc->async_tx.phys;
 666                         ioat_chan->desccount++;
 667                 }
 668
 669                 ioat_chan->used_desc.next = noop_desc->node.next;
 670         }
 671         new = to_ioat_desc(ioat_chan->used_desc.next);
 672         prefetch(new);
 673         ioat_chan->used_desc.next = new->node.next;
 674
 675         if (ioat_chan->used_desc.prev == NULL)
 676                 ioat_chan->used_desc.prev = &new->node;
 677
 678         prefetch(new->hw);
 679         return new;
 680 }
 681
 682 static struct ioat_desc_sw *ioat_dma_get_next_descriptor(
 683                                                 struct ioat_dma_chan *ioat_chan)
 684 {
 685         if (!ioat_chan)
 686                 return NULL;
 687
 688         switch (ioat_chan->device->version) {
 689         case IOAT_VER_1_2:
 690                 return ioat1_dma_get_next_descriptor(ioat_chan);
 691                 break;
 692         case IOAT_VER_2_0:
 693                 return ioat2_dma_get_next_descriptor(ioat_chan);
 694                 break;
 695         }
 696         return NULL;
 697 }
 698
 699 static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
 700                                                 struct dma_chan *chan,
 701                                                 dma_addr_t dma_dest,
 702                                                 dma_addr_t dma_src,
 703                                                 size_t len,
 704                                                 unsigned long flags)
 705 {
 706         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 707         struct ioat_desc_sw *new;
 708
 709         spin_lock_bh(&ioat_chan->desc_lock);
 710         new = ioat_dma_get_next_descriptor(ioat_chan);
 711         spin_unlock_bh(&ioat_chan->desc_lock);
 712
 713         if (new) {
 714                 new->len = len;
 715                 new->dst = dma_dest;
 716                 new->src = dma_src;
 717                 new->async_tx.ack = 0;
 718                 return &new->async_tx;
 719         } else
 720                 return NULL;
 721 }
 722
 723 static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
 724                                                 struct dma_chan *chan,
 725                                                 dma_addr_t dma_dest,
 726                                                 dma_addr_t dma_src,
 727                                                 size_t len,
 728                                                 unsigned long flags)
 729 {
 730         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 731         struct ioat_desc_sw *new;
 732
 733         spin_lock_bh(&ioat_chan->desc_lock);
 734         new = ioat2_dma_get_next_descriptor(ioat_chan);
 735
 736         /*
 737          * leave ioat_chan->desc_lock set in ioat 2 path
 738          * it will get unlocked at end of tx_submit
 739          */
 740
 741         if (new) {
 742                 new->len = len;
 743                 new->dst = dma_dest;
 744                 new->src = dma_src;
 745                 new->async_tx.ack = 0;
 746                 return &new->async_tx;
 747         } else
 748                 return NULL;
 749 }
 750
 751 static void ioat_dma_cleanup_tasklet(unsigned long data)
 752 {
 753         struct ioat_dma_chan *chan = (void *)data;
 754         ioat_dma_memcpy_cleanup(chan);
 755         writew(IOAT_CHANCTRL_INT_DISABLE,
 756                chan->reg_base + IOAT_CHANCTRL_OFFSET);
 757 }
 758
 759 /**
 760  * ioat_dma_memcpy_cleanup - cleanup up finished descriptors
 761  * @chan: ioat channel to be cleaned up
 762  */
 763 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
 764 {
 765         unsigned long phys_complete;
 766         struct ioat_desc_sw *desc, *_desc;
 767         dma_cookie_t cookie = 0;
 768         unsigned long desc_phys;
 769         struct ioat_desc_sw *latest_desc;
 770
 771         prefetch(ioat_chan->completion_virt);
 772
 773         if (!spin_trylock_bh(&ioat_chan->cleanup_lock))
 774                 return;
 775
 776         /* The completion writeback can happen at any time,
 777            so reads by the driver need to be atomic operations
 778            The descriptor physical addresses are limited to 32-bits
 779            when the CPU can only do a 32-bit mov */
 780
 781 #if (BITS_PER_LONG == 64)
 782         phys_complete =
 783                 ioat_chan->completion_virt->full
 784                 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
 785 #else
 786         phys_complete =
 787                 ioat_chan->completion_virt->low & IOAT_LOW_COMPLETION_MASK;
 788 #endif
 789
 790         if ((ioat_chan->completion_virt->full
 791                 & IOAT_CHANSTS_DMA_TRANSFER_STATUS) ==
 792                                 IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) {
 793                 dev_err(&ioat_chan->device->pdev->dev,
 794                         "Channel halted, chanerr = %x\n",
 795                         readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET));
 796
 797                 /* TODO do something to salvage the situation */
 798         }
 799
 800         if (phys_complete == ioat_chan->last_completion) {
 801                 spin_unlock_bh(&ioat_chan->cleanup_lock);
 802                 return;
 803         }
 804
 805         cookie = 0;
 806         spin_lock_bh(&ioat_chan->desc_lock);
 807         switch (ioat_chan->device->version) {
 808         case IOAT_VER_1_2:
 809                 list_for_each_entry_safe(desc, _desc,
 810                                          &ioat_chan->used_desc, node) {
 811
 812                         /*
 813                          * Incoming DMA requests may use multiple descriptors,
 814                          * due to exceeding xfercap, perhaps. If so, only the
 815                          * last one will have a cookie, and require unmapping.
 816                          */
 817                         if (desc->async_tx.cookie) {
 818                                 cookie = desc->async_tx.cookie;
 819
 820                                 /*
 821                                  * yes we are unmapping both _page and _single
 822                                  * alloc'd regions with unmap_page. Is this
 823                                  * *really* that bad?
 824                                  */
 825                                 pci_unmap_page(ioat_chan->device->pdev,
 826                                                 pci_unmap_addr(desc, dst),
 827                                                 pci_unmap_len(desc, len),
 828                                                 PCI_DMA_FROMDEVICE);
 829                                 pci_unmap_page(ioat_chan->device->pdev,
 830                                                 pci_unmap_addr(desc, src),
 831                                                 pci_unmap_len(desc, len),
 832                                                 PCI_DMA_TODEVICE);
 833
 834                                 if (desc->async_tx.callback) {
 835                                         desc->async_tx.callback(desc->async_tx.callback_param);
 836                                         desc->async_tx.callback = NULL;
 837                                 }
 838                         }
 839
 840                         if (desc->async_tx.phys != phys_complete) {
 841                                 /*
 842                                  * a completed entry, but not the last, so clean
 843                                  * up if the client is done with the descriptor
 844                                  */
 845                                 if (desc->async_tx.ack) {
 846                                         list_del(&desc->node);
 847                                         list_add_tail(&desc->node,
 848                                                       &ioat_chan->free_desc);
 849                                 } else
 850                                         desc->async_tx.cookie = 0;
 851                         } else {
 852                                 /*
 853                                  * last used desc. Do not remove, so we can
 854                                  * append from it, but don't look at it next
 855                                  * time, either
 856                                  */
 857                                 desc->async_tx.cookie = 0;
 858
 859                                 /* TODO check status bits? */
 860                                 break;
 861                         }
 862                 }
 863                 break;
 864         case IOAT_VER_2_0:
 865                 /* has some other thread has already cleaned up? */
 866                 if (ioat_chan->used_desc.prev == NULL)
 867                         break;
 868
 869                 /* work backwards to find latest finished desc */
 870                 desc = to_ioat_desc(ioat_chan->used_desc.next);
 871                 latest_desc = NULL;
 872                 do {
 873                         desc = to_ioat_desc(desc->node.prev);
 874                         desc_phys = (unsigned long)desc->async_tx.phys
 875                                        & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
 876                         if (desc_phys == phys_complete) {
 877                                 latest_desc = desc;
 878                                 break;
 879                         }
 880                 } while (&desc->node != ioat_chan->used_desc.prev);
 881
 882                 if (latest_desc != NULL) {
 883
 884                         /* work forwards to clear finished descriptors */
 885                         for (desc = to_ioat_desc(ioat_chan->used_desc.prev);
 886                              &desc->node != latest_desc->node.next &&
 887                              &desc->node != ioat_chan->used_desc.next;
 888                              desc = to_ioat_desc(desc->node.next)) {
 889                                 if (desc->async_tx.cookie) {
 890                                         cookie = desc->async_tx.cookie;
 891                                         desc->async_tx.cookie = 0;
 892
 893                                         pci_unmap_page(ioat_chan->device->pdev,
 894                                                       pci_unmap_addr(desc, dst),
 895                                                       pci_unmap_len(desc, len),
 896                                                       PCI_DMA_FROMDEVICE);
 897                                         pci_unmap_page(ioat_chan->device->pdev,
 898                                                       pci_unmap_addr(desc, src),
 899                                                       pci_unmap_len(desc, len),
 900                                                       PCI_DMA_TODEVICE);
 901
 902                                         if (desc->async_tx.callback) {
 903                                                 desc->async_tx.callback(desc->async_tx.callback_param);
 904                                                 desc->async_tx.callback = NULL;
 905                                         }
 906                                 }
 907                         }
 908
 909                         /* move used.prev up beyond those that are finished */
 910                         if (&desc->node == ioat_chan->used_desc.next)
 911                                 ioat_chan->used_desc.prev = NULL;
 912                         else
 913                                 ioat_chan->used_desc.prev = &desc->node;
 914                 }
 915                 break;
 916         }
 917
 918         spin_unlock_bh(&ioat_chan->desc_lock);
 919
 920         ioat_chan->last_completion = phys_complete;
 921         if (cookie != 0)
 922                 ioat_chan->completed_cookie = cookie;
 923
 924         spin_unlock_bh(&ioat_chan->cleanup_lock);
 925 }
 926
 927 static void ioat_dma_dependency_added(struct dma_chan *chan)
 928 {
 929         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 930         spin_lock_bh(&ioat_chan->desc_lock);
 931         if (ioat_chan->pending == 0) {
 932                 spin_unlock_bh(&ioat_chan->desc_lock);
 933                 ioat_dma_memcpy_cleanup(ioat_chan);
 934         } else
 935                 spin_unlock_bh(&ioat_chan->desc_lock);
 936 }
 937
 938 /**
 939  * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
 940  * @chan: IOAT DMA channel handle
 941  * @cookie: DMA transaction identifier
 942  * @done: if not %NULL, updated with last completed transaction
 943  * @used: if not %NULL, updated with last used transaction
 944  */
 945 static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
 946                                             dma_cookie_t cookie,
 947                                             dma_cookie_t *done,
 948                                             dma_cookie_t *used)
 949 {
 950         struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
 951         dma_cookie_t last_used;
 952         dma_cookie_t last_complete;
 953         enum dma_status ret;
 954
 955         last_used = chan->cookie;
 956         last_complete = ioat_chan->completed_cookie;
 957
 958         if (done)
 959                 *done = last_complete;
 960         if (used)
 961                 *used = last_used;
 962
 963         ret = dma_async_is_complete(cookie, last_complete, last_used);
 964         if (ret == DMA_SUCCESS)
 965                 return ret;
 966
 967         ioat_dma_memcpy_cleanup(ioat_chan);
 968
 969         last_used = chan->cookie;
 970         last_complete = ioat_chan->completed_cookie;
 971
 972         if (done)
 973                 *done = last_complete;
 974         if (used)
 975                 *used = last_used;
 976
 977         return dma_async_is_complete(cookie, last_complete, last_used);
 978 }
 979
 980 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
 981 {
 982         struct ioat_desc_sw *desc;
 983
 984         spin_lock_bh(&ioat_chan->desc_lock);
 985
 986         desc = ioat_dma_get_next_descriptor(ioat_chan);
 987         desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL
 988                                 | IOAT_DMA_DESCRIPTOR_CTL_INT_GN
 989                                 | IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
 990         desc->hw->size = 0;
 991         desc->hw->src_addr = 0;
 992         desc->hw->dst_addr = 0;
 993         desc->async_tx.ack = 1;
 994         switch (ioat_chan->device->version) {
 995         case IOAT_VER_1_2:
 996                 desc->hw->next = 0;
 997                 list_add_tail(&desc->node, &ioat_chan->used_desc);
 998
 999                 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
1000                        ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
1001                 writel(((u64) desc->async_tx.phys) >> 32,
1002                        ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
1003
1004                 writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
1005                         + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
1006                 break;
1007         case IOAT_VER_2_0:
1008                 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
1009                        ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
1010                 writel(((u64) desc->async_tx.phys) >> 32,
1011                        ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
1012
1013                 ioat_chan->dmacount++;
1014                 __ioat2_dma_memcpy_issue_pending(ioat_chan);
1015                 break;
1016         }
1017         spin_unlock_bh(&ioat_chan->desc_lock);
1018 }
1019
1020 /*
1021  * Perform a IOAT transaction to verify the HW works.
1022  */
1023 #define IOAT_TEST_SIZE 2000
1024
1025 static void ioat_dma_test_callback(void *dma_async_param)
1026 {
1027         printk(KERN_ERR "ioatdma: ioat_dma_test_callback(%p)\n",
1028                 dma_async_param);
1029 }
1030
1031 /**
1032  * ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
1033  * @device: device to be tested
1034  */
1035 static int ioat_dma_self_test(struct ioatdma_device *device)
1036 {
1037         int i;
1038         u8 *src;
1039         u8 *dest;
1040         struct dma_chan *dma_chan;
1041         struct dma_async_tx_descriptor *tx;
1042         dma_addr_t dma_dest, dma_src;
1043         dma_cookie_t cookie;
1044         int err = 0;
1045
1046         src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1047         if (!src)
1048                 return -ENOMEM;
1049         dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1050         if (!dest) {
1051                 kfree(src);
1052                 return -ENOMEM;
1053         }
1054
1055         /* Fill in src buffer */
1056         for (i = 0; i < IOAT_TEST_SIZE; i++)
1057                 src[i] = (u8)i;
1058
1059         /* Start copy, using first DMA channel */
1060         dma_chan = container_of(device->common.channels.next,
1061                                 struct dma_chan,
1062                                 device_node);
1063         if (device->common.device_alloc_chan_resources(dma_chan) < 1) {
1064                 dev_err(&device->pdev->dev,
1065                         "selftest cannot allocate chan resource\n");
1066                 err = -ENODEV;
1067                 goto out;
1068         }
1069
1070         dma_src = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
1071                                  DMA_TO_DEVICE);
1072         dma_dest = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
1073                                   DMA_FROM_DEVICE);
1074         tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
1075                                                    IOAT_TEST_SIZE, 0);
1076         if (!tx) {
1077                 dev_err(&device->pdev->dev,
1078                         "Self-test prep failed, disabling\n");
1079                 err = -ENODEV;
1080                 goto free_resources;
1081         }
1082
1083         async_tx_ack(tx);
1084         tx->callback = ioat_dma_test_callback;
1085         tx->callback_param = (void *)0x8086;
1086         cookie = tx->tx_submit(tx);
1087         if (cookie < 0) {
1088                 dev_err(&device->pdev->dev,
1089                         "Self-test setup failed, disabling\n");
1090                 err = -ENODEV;
1091                 goto free_resources;
1092         }
1093         device->common.device_issue_pending(dma_chan);
1094         msleep(1);
1095
1096         if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
1097                                         != DMA_SUCCESS) {
1098                 dev_err(&device->pdev->dev,
1099                         "Self-test copy timed out, disabling\n");
1100                 err = -ENODEV;
1101                 goto free_resources;
1102         }
1103         if (memcmp(src, dest, IOAT_TEST_SIZE)) {
1104                 dev_err(&device->pdev->dev,
1105                         "Self-test copy failed compare, disabling\n");
1106                 err = -ENODEV;
1107                 goto free_resources;
1108         }
1109
1110 free_resources:
1111         device->common.device_free_chan_resources(dma_chan);
1112 out:
1113         kfree(src);
1114         kfree(dest);
1115         return err;
1116 }
1117
1118 static char ioat_interrupt_style[32] = "msix";
1119 module_param_string(ioat_interrupt_style, ioat_interrupt_style,
1120                     sizeof(ioat_interrupt_style), 0644);
1121 MODULE_PARM_DESC(ioat_interrupt_style,
1122                  "set ioat interrupt style: msix (default), "
1123                  "msix-single-vector, msi, intx)");
1124
1125 /**
1126  * ioat_dma_setup_interrupts - setup interrupt handler
1127  * @device: ioat device
1128  */
1129 static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
1130 {
1131         struct ioat_dma_chan *ioat_chan;
1132         int err, i, j, msixcnt;
1133         u8 intrctrl = 0;
1134
1135         if (!strcmp(ioat_interrupt_style, "msix"))
1136                 goto msix;
1137         if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
1138                 goto msix_single_vector;
1139         if (!strcmp(ioat_interrupt_style, "msi"))
1140                 goto msi;
1141         if (!strcmp(ioat_interrupt_style, "intx"))
1142                 goto intx;
1143         dev_err(&device->pdev->dev, "invalid ioat_interrupt_style %s\n",
1144                 ioat_interrupt_style);
1145         goto err_no_irq;
1146
1147 msix:
1148         /* The number of MSI-X vectors should equal the number of channels */
1149         msixcnt = device->common.chancnt;
1150         for (i = 0; i < msixcnt; i++)
1151                 device->msix_entries[i].entry = i;
1152
1153         err = pci_enable_msix(device->pdev, device->msix_entries, msixcnt);
1154         if (err < 0)
1155                 goto msi;
1156         if (err > 0)
1157                 goto msix_single_vector;
1158
1159         for (i = 0; i < msixcnt; i++) {
1160                 ioat_chan = ioat_lookup_chan_by_index(device, i);
1161                 err = request_irq(device->msix_entries[i].vector,
1162                                   ioat_dma_do_interrupt_msix,
1163                                   0, "ioat-msix", ioat_chan);
1164                 if (err) {
1165                         for (j = 0; j < i; j++) {
1166                                 ioat_chan =
1167                                         ioat_lookup_chan_by_index(device, j);
1168                                 free_irq(device->msix_entries[j].vector,
1169                                          ioat_chan);
1170                         }
1171                         goto msix_single_vector;
1172                 }
1173         }
1174         intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
1175         device->irq_mode = msix_multi_vector;
1176         goto done;
1177
1178 msix_single_vector:
1179         device->msix_entries[0].entry = 0;
1180         err = pci_enable_msix(device->pdev, device->msix_entries, 1);
1181         if (err)
1182                 goto msi;
1183
1184         err = request_irq(device->msix_entries[0].vector, ioat_dma_do_interrupt,
1185                           0, "ioat-msix", device);
1186         if (err) {
1187                 pci_disable_msix(device->pdev);
1188                 goto msi;
1189         }
1190         device->irq_mode = msix_single_vector;
1191         goto done;
1192
1193 msi:
1194         err = pci_enable_msi(device->pdev);
1195         if (err)
1196                 goto intx;
1197
1198         err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1199                           0, "ioat-msi", device);
1200         if (err) {
1201                 pci_disable_msi(device->pdev);
1202                 goto intx;
1203         }
1204         /*
1205          * CB 1.2 devices need a bit set in configuration space to enable MSI
1206          */
1207         if (device->version == IOAT_VER_1_2) {
1208                 u32 dmactrl;
1209                 pci_read_config_dword(device->pdev,
1210                                       IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
1211                 dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
1212                 pci_write_config_dword(device->pdev,
1213                                        IOAT_PCI_DMACTRL_OFFSET, dmactrl);
1214         }
1215         device->irq_mode = msi;
1216         goto done;
1217
1218 intx:
1219         err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1220                           IRQF_SHARED, "ioat-intx", device);
1221         if (err)
1222                 goto err_no_irq;
1223         device->irq_mode = intx;
1224
1225 done:
1226         intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
1227         writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
1228         return 0;
1229
1230 err_no_irq:
1231         /* Disable all interrupt generation */
1232         writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1233         dev_err(&device->pdev->dev, "no usable interrupts\n");
1234         device->irq_mode = none;
1235         return -1;
1236 }
1237
1238 /**
1239  * ioat_dma_remove_interrupts - remove whatever interrupts were set
1240  * @device: ioat device
1241  */
1242 static void ioat_dma_remove_interrupts(struct ioatdma_device *device)
1243 {
1244         struct ioat_dma_chan *ioat_chan;
1245         int i;
1246
1247         /* Disable all interrupt generation */
1248         writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1249
1250         switch (device->irq_mode) {
1251         case msix_multi_vector:
1252                 for (i = 0; i < device->common.chancnt; i++) {
1253                         ioat_chan = ioat_lookup_chan_by_index(device, i);
1254                         free_irq(device->msix_entries[i].vector, ioat_chan);
1255                 }
1256                 pci_disable_msix(device->pdev);
1257                 break;
1258         case msix_single_vector:
1259                 free_irq(device->msix_entries[0].vector, device);
1260                 pci_disable_msix(device->pdev);
1261                 break;
1262         case msi:
1263                 free_irq(device->pdev->irq, device);
1264                 pci_disable_msi(device->pdev);
1265                 break;
1266         case intx:
1267                 free_irq(device->pdev->irq, device);
1268                 break;
1269         case none:
1270                 dev_warn(&device->pdev->dev,
1271                          "call to %s without interrupts setup\n", __func__);
1272         }
1273         device->irq_mode = none;
1274 }
1275
1276 struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
1277                                       void __iomem *iobase)
1278 {
1279         int err;
1280         struct ioatdma_device *device;
1281
1282         device = kzalloc(sizeof(*device), GFP_KERNEL);
1283         if (!device) {
1284                 err = -ENOMEM;
1285                 goto err_kzalloc;
1286         }
1287         device->pdev = pdev;
1288         device->reg_base = iobase;
1289         device->version = readb(device->reg_base + IOAT_VER_OFFSET);
1290
1291         /* DMA coherent memory pool for DMA descriptor allocations */
1292         device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
1293                                            sizeof(struct ioat_dma_descriptor),
1294                                            64, 0);
1295         if (!device->dma_pool) {
1296                 err = -ENOMEM;
1297                 goto err_dma_pool;
1298         }
1299
1300         device->completion_pool = pci_pool_create("completion_pool", pdev,
1301                                                   sizeof(u64), SMP_CACHE_BYTES,
1302                                                   SMP_CACHE_BYTES);
1303         if (!device->completion_pool) {
1304                 err = -ENOMEM;
1305                 goto err_completion_pool;
1306         }
1307
1308         INIT_LIST_HEAD(&device->common.channels);
1309         ioat_dma_enumerate_channels(device);
1310
1311         device->common.device_alloc_chan_resources =
1312                                                 ioat_dma_alloc_chan_resources;
1313         device->common.device_free_chan_resources =
1314                                                 ioat_dma_free_chan_resources;
1315         device->common.dev = &pdev->dev;
1316
1317         dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
1318         device->common.device_is_tx_complete = ioat_dma_is_complete;
1319         device->common.device_dependency_added = ioat_dma_dependency_added;
1320         switch (device->version) {
1321         case IOAT_VER_1_2:
1322                 device->common.device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
1323                 device->common.device_issue_pending =
1324                                                 ioat1_dma_memcpy_issue_pending;
1325                 break;
1326         case IOAT_VER_2_0:
1327                 device->common.device_prep_dma_memcpy = ioat2_dma_prep_memcpy;
1328                 device->common.device_issue_pending =
1329                                                 ioat2_dma_memcpy_issue_pending;
1330                 break;
1331         }
1332
1333         dev_err(&device->pdev->dev,
1334                 "Intel(R) I/OAT DMA Engine found,"
1335                 " %d channels, device version 0x%02x, driver version %s\n",
1336                 device->common.chancnt, device->version, IOAT_DMA_VERSION);
1337
1338         err = ioat_dma_setup_interrupts(device);
1339         if (err)
1340                 goto err_setup_interrupts;
1341
1342         err = ioat_dma_self_test(device);
1343         if (err)
1344                 goto err_self_test;
1345
1346         dma_async_device_register(&device->common);
1347
1348         return device;
1349
1350 err_self_test:
1351         ioat_dma_remove_interrupts(device);
1352 err_setup_interrupts:
1353         pci_pool_destroy(device->completion_pool);
1354 err_completion_pool:
1355         pci_pool_destroy(device->dma_pool);
1356 err_dma_pool:
1357         kfree(device);
1358 err_kzalloc:
1359         dev_err(&pdev->dev,
1360                 "Intel(R) I/OAT DMA Engine initialization failed\n");
1361         return NULL;
1362 }
1363
1364 void ioat_dma_remove(struct ioatdma_device *device)
1365 {
1366         struct dma_chan *chan, *_chan;
1367         struct ioat_dma_chan *ioat_chan;
1368
1369         ioat_dma_remove_interrupts(device);
1370
1371         dma_async_device_unregister(&device->common);
1372
1373         pci_pool_destroy(device->dma_pool);
1374         pci_pool_destroy(device->completion_pool);
1375
1376         iounmap(device->reg_base);
1377         pci_release_regions(device->pdev);
1378         pci_disable_device(device->pdev);
1379
1380         list_for_each_entry_safe(chan, _chan,
1381                                  &device->common.channels, device_node) {
1382                 ioat_chan = to_ioat_chan(chan);
1383                 list_del(&chan->device_node);
1384                 kfree(ioat_chan);
1385         }
1386         kfree(device);
1387 }
1388