drivers/net/wireless/b43legacy/dma.c

   1 /*
   2
   3   Broadcom B43legacy wireless driver
   4
   5   DMA ringbuffer and descriptor allocation/management
   6
   7   Copyright (c) 2005, 2006 Michael Buesch <mb@bu3sch.de>
   8
   9   Some code in this file is derived from the b44.c driver
  10   Copyright (C) 2002 David S. Miller
  11   Copyright (C) Pekka Pietikainen
  12
  13   This program is free software; you can redistribute it and/or modify
  14   it under the terms of the GNU General Public License as published by
  15   the Free Software Foundation; either version 2 of the License, or
  16   (at your option) any later version.
  17
  18   This program is distributed in the hope that it will be useful,
  19   but WITHOUT ANY WARRANTY; without even the implied warranty of
  20   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21   GNU General Public License for more details.
  22
  23   You should have received a copy of the GNU General Public License
  24   along with this program; see the file COPYING.  If not, write to
  25   the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
  26   Boston, MA 02110-1301, USA.
  27
  28 */
  29
  30 #include "b43legacy.h"
  31 #include "dma.h"
  32 #include "main.h"
  33 #include "debugfs.h"
  34 #include "xmit.h"
  35
  36 #include <linux/dma-mapping.h>
  37 #include <linux/pci.h>
  38 #include <linux/delay.h>
  39 #include <linux/skbuff.h>
  40 #include <linux/slab.h>
  41 #include <net/dst.h>
  42
  43 /* 32bit DMA ops. */
  44 static
  45 struct b43legacy_dmadesc_generic *op32_idx2desc(
  46                                         struct b43legacy_dmaring *ring,
  47                                         int slot,
  48                                         struct b43legacy_dmadesc_meta **meta)
  49 {
  50         struct b43legacy_dmadesc32 *desc;
  51
  52         *meta = &(ring->meta[slot]);
  53         desc = ring->descbase;
  54         desc = &(desc[slot]);
  55
  56         return (struct b43legacy_dmadesc_generic *)desc;
  57 }
  58
  59 static void op32_fill_descriptor(struct b43legacy_dmaring *ring,
  60                                  struct b43legacy_dmadesc_generic *desc,
  61                                  dma_addr_t dmaaddr, u16 bufsize,
  62                                  int start, int end, int irq)
  63 {
  64         struct b43legacy_dmadesc32 *descbase = ring->descbase;
  65         int slot;
  66         u32 ctl;
  67         u32 addr;
  68         u32 addrext;
  69
  70         slot = (int)(&(desc->dma32) - descbase);
  71         B43legacy_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
  72
  73         addr = (u32)(dmaaddr & ~SSB_DMA_TRANSLATION_MASK);
  74         addrext = (u32)(dmaaddr & SSB_DMA_TRANSLATION_MASK)
  75                    >> SSB_DMA_TRANSLATION_SHIFT;
  76         addr |= ssb_dma_translation(ring->dev->dev);
  77         ctl = (bufsize - ring->frameoffset)
  78               & B43legacy_DMA32_DCTL_BYTECNT;
  79         if (slot == ring->nr_slots - 1)
  80                 ctl |= B43legacy_DMA32_DCTL_DTABLEEND;
  81         if (start)
  82                 ctl |= B43legacy_DMA32_DCTL_FRAMESTART;
  83         if (end)
  84                 ctl |= B43legacy_DMA32_DCTL_FRAMEEND;
  85         if (irq)
  86                 ctl |= B43legacy_DMA32_DCTL_IRQ;
  87         ctl |= (addrext << B43legacy_DMA32_DCTL_ADDREXT_SHIFT)
  88                & B43legacy_DMA32_DCTL_ADDREXT_MASK;
  89
  90         desc->dma32.control = cpu_to_le32(ctl);
  91         desc->dma32.address = cpu_to_le32(addr);
  92 }
  93
  94 static void op32_poke_tx(struct b43legacy_dmaring *ring, int slot)
  95 {
  96         b43legacy_dma_write(ring, B43legacy_DMA32_TXINDEX,
  97                             (u32)(slot * sizeof(struct b43legacy_dmadesc32)));
  98 }
  99
 100 static void op32_tx_suspend(struct b43legacy_dmaring *ring)
 101 {
 102         b43legacy_dma_write(ring, B43legacy_DMA32_TXCTL,
 103                             b43legacy_dma_read(ring, B43legacy_DMA32_TXCTL)
 104                             | B43legacy_DMA32_TXSUSPEND);
 105 }
 106
 107 static void op32_tx_resume(struct b43legacy_dmaring *ring)
 108 {
 109         b43legacy_dma_write(ring, B43legacy_DMA32_TXCTL,
 110                             b43legacy_dma_read(ring, B43legacy_DMA32_TXCTL)
 111                             & ~B43legacy_DMA32_TXSUSPEND);
 112 }
 113
 114 static int op32_get_current_rxslot(struct b43legacy_dmaring *ring)
 115 {
 116         u32 val;
 117
 118         val = b43legacy_dma_read(ring, B43legacy_DMA32_RXSTATUS);
 119         val &= B43legacy_DMA32_RXDPTR;
 120
 121         return (val / sizeof(struct b43legacy_dmadesc32));
 122 }
 123
 124 static void op32_set_current_rxslot(struct b43legacy_dmaring *ring,
 125                                     int slot)
 126 {
 127         b43legacy_dma_write(ring, B43legacy_DMA32_RXINDEX,
 128                             (u32)(slot * sizeof(struct b43legacy_dmadesc32)));
 129 }
 130
 131 static const struct b43legacy_dma_ops dma32_ops = {
 132         .idx2desc               = op32_idx2desc,
 133         .fill_descriptor        = op32_fill_descriptor,
 134         .poke_tx                = op32_poke_tx,
 135         .tx_suspend             = op32_tx_suspend,
 136         .tx_resume              = op32_tx_resume,
 137         .get_current_rxslot     = op32_get_current_rxslot,
 138         .set_current_rxslot     = op32_set_current_rxslot,
 139 };
 140
 141 /* 64bit DMA ops. */
 142 static
 143 struct b43legacy_dmadesc_generic *op64_idx2desc(
 144                                         struct b43legacy_dmaring *ring,
 145                                         int slot,
 146                                         struct b43legacy_dmadesc_meta
 147                                         **meta)
 148 {
 149         struct b43legacy_dmadesc64 *desc;
 150
 151         *meta = &(ring->meta[slot]);
 152         desc = ring->descbase;
 153         desc = &(desc[slot]);
 154
 155         return (struct b43legacy_dmadesc_generic *)desc;
 156 }
 157
 158 static void op64_fill_descriptor(struct b43legacy_dmaring *ring,
 159                                  struct b43legacy_dmadesc_generic *desc,
 160                                  dma_addr_t dmaaddr, u16 bufsize,
 161                                  int start, int end, int irq)
 162 {
 163         struct b43legacy_dmadesc64 *descbase = ring->descbase;
 164         int slot;
 165         u32 ctl0 = 0;
 166         u32 ctl1 = 0;
 167         u32 addrlo;
 168         u32 addrhi;
 169         u32 addrext;
 170
 171         slot = (int)(&(desc->dma64) - descbase);
 172         B43legacy_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
 173
 174         addrlo = (u32)(dmaaddr & 0xFFFFFFFF);
 175         addrhi = (((u64)dmaaddr >> 32) & ~SSB_DMA_TRANSLATION_MASK);
 176         addrext = (((u64)dmaaddr >> 32) & SSB_DMA_TRANSLATION_MASK)
 177                   >> SSB_DMA_TRANSLATION_SHIFT;
 178         addrhi |= ssb_dma_translation(ring->dev->dev);
 179         if (slot == ring->nr_slots - 1)
 180                 ctl0 |= B43legacy_DMA64_DCTL0_DTABLEEND;
 181         if (start)
 182                 ctl0 |= B43legacy_DMA64_DCTL0_FRAMESTART;
 183         if (end)
 184                 ctl0 |= B43legacy_DMA64_DCTL0_FRAMEEND;
 185         if (irq)
 186                 ctl0 |= B43legacy_DMA64_DCTL0_IRQ;
 187         ctl1 |= (bufsize - ring->frameoffset)
 188                 & B43legacy_DMA64_DCTL1_BYTECNT;
 189         ctl1 |= (addrext << B43legacy_DMA64_DCTL1_ADDREXT_SHIFT)
 190                 & B43legacy_DMA64_DCTL1_ADDREXT_MASK;
 191
 192         desc->dma64.control0 = cpu_to_le32(ctl0);
 193         desc->dma64.control1 = cpu_to_le32(ctl1);
 194         desc->dma64.address_low = cpu_to_le32(addrlo);
 195         desc->dma64.address_high = cpu_to_le32(addrhi);
 196 }
 197
 198 static void op64_poke_tx(struct b43legacy_dmaring *ring, int slot)
 199 {
 200         b43legacy_dma_write(ring, B43legacy_DMA64_TXINDEX,
 201                             (u32)(slot * sizeof(struct b43legacy_dmadesc64)));
 202 }
 203
 204 static void op64_tx_suspend(struct b43legacy_dmaring *ring)
 205 {
 206         b43legacy_dma_write(ring, B43legacy_DMA64_TXCTL,
 207                             b43legacy_dma_read(ring, B43legacy_DMA64_TXCTL)
 208                             | B43legacy_DMA64_TXSUSPEND);
 209 }
 210
 211 static void op64_tx_resume(struct b43legacy_dmaring *ring)
 212 {
 213         b43legacy_dma_write(ring, B43legacy_DMA64_TXCTL,
 214                             b43legacy_dma_read(ring, B43legacy_DMA64_TXCTL)
 215                             & ~B43legacy_DMA64_TXSUSPEND);
 216 }
 217
 218 static int op64_get_current_rxslot(struct b43legacy_dmaring *ring)
 219 {
 220         u32 val;
 221
 222         val = b43legacy_dma_read(ring, B43legacy_DMA64_RXSTATUS);
 223         val &= B43legacy_DMA64_RXSTATDPTR;
 224
 225         return (val / sizeof(struct b43legacy_dmadesc64));
 226 }
 227
 228 static void op64_set_current_rxslot(struct b43legacy_dmaring *ring,
 229                                     int slot)
 230 {
 231         b43legacy_dma_write(ring, B43legacy_DMA64_RXINDEX,
 232                             (u32)(slot * sizeof(struct b43legacy_dmadesc64)));
 233 }
 234
 235 static const struct b43legacy_dma_ops dma64_ops = {
 236         .idx2desc               = op64_idx2desc,
 237         .fill_descriptor        = op64_fill_descriptor,
 238         .poke_tx                = op64_poke_tx,
 239         .tx_suspend             = op64_tx_suspend,
 240         .tx_resume              = op64_tx_resume,
 241         .get_current_rxslot     = op64_get_current_rxslot,
 242         .set_current_rxslot     = op64_set_current_rxslot,
 243 };
 244
 245
 246 static inline int free_slots(struct b43legacy_dmaring *ring)
 247 {
 248         return (ring->nr_slots - ring->used_slots);
 249 }
 250
 251 static inline int next_slot(struct b43legacy_dmaring *ring, int slot)
 252 {
 253         B43legacy_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
 254         if (slot == ring->nr_slots - 1)
 255                 return 0;
 256         return slot + 1;
 257 }
 258
 259 static inline int prev_slot(struct b43legacy_dmaring *ring, int slot)
 260 {
 261         B43legacy_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
 262         if (slot == 0)
 263                 return ring->nr_slots - 1;
 264         return slot - 1;
 265 }
 266
 267 #ifdef CONFIG_B43LEGACY_DEBUG
 268 static void update_max_used_slots(struct b43legacy_dmaring *ring,
 269                                   int current_used_slots)
 270 {
 271         if (current_used_slots <= ring->max_used_slots)
 272                 return;
 273         ring->max_used_slots = current_used_slots;
 274         if (b43legacy_debug(ring->dev, B43legacy_DBG_DMAVERBOSE))
 275                 b43legacydbg(ring->dev->wl,
 276                        "max_used_slots increased to %d on %s ring %d\n",
 277                        ring->max_used_slots,
 278                        ring->tx ? "TX" : "RX",
 279                        ring->index);
 280 }
 281 #else
 282 static inline
 283 void update_max_used_slots(struct b43legacy_dmaring *ring,
 284                            int current_used_slots)
 285 { }
 286 #endif /* DEBUG */
 287
 288 /* Request a slot for usage. */
 289 static inline
 290 int request_slot(struct b43legacy_dmaring *ring)
 291 {
 292         int slot;
 293
 294         B43legacy_WARN_ON(!ring->tx);
 295         B43legacy_WARN_ON(ring->stopped);
 296         B43legacy_WARN_ON(free_slots(ring) == 0);
 297
 298         slot = next_slot(ring, ring->current_slot);
 299         ring->current_slot = slot;
 300         ring->used_slots++;
 301
 302         update_max_used_slots(ring, ring->used_slots);
 303
 304         return slot;
 305 }
 306
 307 /* Mac80211-queue to b43legacy-ring mapping */
 308 static struct b43legacy_dmaring *priority_to_txring(
 309                                                 struct b43legacy_wldev *dev,
 310                                                 int queue_priority)
 311 {
 312         struct b43legacy_dmaring *ring;
 313
 314 /*FIXME: For now we always run on TX-ring-1 */
 315 return dev->dma.tx_ring1;
 316
 317         /* 0 = highest priority */
 318         switch (queue_priority) {
 319         default:
 320                 B43legacy_WARN_ON(1);
 321                 /* fallthrough */
 322         case 0:
 323                 ring = dev->dma.tx_ring3;
 324                 break;
 325         case 1:
 326                 ring = dev->dma.tx_ring2;
 327                 break;
 328         case 2:
 329                 ring = dev->dma.tx_ring1;
 330                 break;
 331         case 3:
 332                 ring = dev->dma.tx_ring0;
 333                 break;
 334         case 4:
 335                 ring = dev->dma.tx_ring4;
 336                 break;
 337         case 5:
 338                 ring = dev->dma.tx_ring5;
 339                 break;
 340         }
 341
 342         return ring;
 343 }
 344
 345 /* Bcm4301-ring to mac80211-queue mapping */
 346 static inline int txring_to_priority(struct b43legacy_dmaring *ring)
 347 {
 348         static const u8 idx_to_prio[] =
 349                 { 3, 2, 1, 0, 4, 5, };
 350
 351 /*FIXME: have only one queue, for now */
 352 return 0;
 353
 354         return idx_to_prio[ring->index];
 355 }
 356
 357
 358 static u16 b43legacy_dmacontroller_base(enum b43legacy_dmatype type,
 359                                         int controller_idx)
 360 {
 361         static const u16 map64[] = {
 362                 B43legacy_MMIO_DMA64_BASE0,
 363                 B43legacy_MMIO_DMA64_BASE1,
 364                 B43legacy_MMIO_DMA64_BASE2,
 365                 B43legacy_MMIO_DMA64_BASE3,
 366                 B43legacy_MMIO_DMA64_BASE4,
 367                 B43legacy_MMIO_DMA64_BASE5,
 368         };
 369         static const u16 map32[] = {
 370                 B43legacy_MMIO_DMA32_BASE0,
 371                 B43legacy_MMIO_DMA32_BASE1,
 372                 B43legacy_MMIO_DMA32_BASE2,
 373                 B43legacy_MMIO_DMA32_BASE3,
 374                 B43legacy_MMIO_DMA32_BASE4,
 375                 B43legacy_MMIO_DMA32_BASE5,
 376         };
 377
 378         if (type == B43legacy_DMA_64BIT) {
 379                 B43legacy_WARN_ON(!(controller_idx >= 0 &&
 380                                   controller_idx < ARRAY_SIZE(map64)));
 381                 return map64[controller_idx];
 382         }
 383         B43legacy_WARN_ON(!(controller_idx >= 0 &&
 384                           controller_idx < ARRAY_SIZE(map32)));
 385         return map32[controller_idx];
 386 }
 387
 388 static inline
 389 dma_addr_t map_descbuffer(struct b43legacy_dmaring *ring,
 390                           unsigned char *buf,
 391                           size_t len,
 392                           int tx)
 393 {
 394         dma_addr_t dmaaddr;
 395
 396         if (tx)
 397                 dmaaddr = ssb_dma_map_single(ring->dev->dev,
 398                                              buf, len,
 399                                              DMA_TO_DEVICE);
 400         else
 401                 dmaaddr = ssb_dma_map_single(ring->dev->dev,
 402                                              buf, len,
 403                                              DMA_FROM_DEVICE);
 404
 405         return dmaaddr;
 406 }
 407
 408 static inline
 409 void unmap_descbuffer(struct b43legacy_dmaring *ring,
 410                       dma_addr_t addr,
 411                       size_t len,
 412                       int tx)
 413 {
 414         if (tx)
 415                 ssb_dma_unmap_single(ring->dev->dev,
 416                                      addr, len,
 417                                      DMA_TO_DEVICE);
 418         else
 419                 ssb_dma_unmap_single(ring->dev->dev,
 420                                      addr, len,
 421                                      DMA_FROM_DEVICE);
 422 }
 423
 424 static inline
 425 void sync_descbuffer_for_cpu(struct b43legacy_dmaring *ring,
 426                              dma_addr_t addr,
 427                              size_t len)
 428 {
 429         B43legacy_WARN_ON(ring->tx);
 430
 431         ssb_dma_sync_single_for_cpu(ring->dev->dev,
 432                                     addr, len, DMA_FROM_DEVICE);
 433 }
 434
 435 static inline
 436 void sync_descbuffer_for_device(struct b43legacy_dmaring *ring,
 437                                 dma_addr_t addr,
 438                                 size_t len)
 439 {
 440         B43legacy_WARN_ON(ring->tx);
 441
 442         ssb_dma_sync_single_for_device(ring->dev->dev,
 443                                        addr, len, DMA_FROM_DEVICE);
 444 }
 445
 446 static inline
 447 void free_descriptor_buffer(struct b43legacy_dmaring *ring,
 448                             struct b43legacy_dmadesc_meta *meta,
 449                             int irq_context)
 450 {
 451         if (meta->skb) {
 452                 if (irq_context)
 453                         dev_kfree_skb_irq(meta->skb);
 454                 else
 455                         dev_kfree_skb(meta->skb);
 456                 meta->skb = NULL;
 457         }
 458 }
 459
 460 static int alloc_ringmemory(struct b43legacy_dmaring *ring)
 461 {
 462         /* GFP flags must match the flags in free_ringmemory()! */
 463         ring->descbase = ssb_dma_alloc_consistent(ring->dev->dev,
 464                                                   B43legacy_DMA_RINGMEMSIZE,
 465                                                   &(ring->dmabase),
 466                                                   GFP_KERNEL);
 467         if (!ring->descbase) {
 468                 b43legacyerr(ring->dev->wl, "DMA ringmemory allocation"
 469                              " failed\n");
 470                 return -ENOMEM;
 471         }
 472         memset(ring->descbase, 0, B43legacy_DMA_RINGMEMSIZE);
 473
 474         return 0;
 475 }
 476
 477 static void free_ringmemory(struct b43legacy_dmaring *ring)
 478 {
 479         ssb_dma_free_consistent(ring->dev->dev, B43legacy_DMA_RINGMEMSIZE,
 480                                 ring->descbase, ring->dmabase, GFP_KERNEL);
 481 }
 482
 483 /* Reset the RX DMA channel */
 484 static int b43legacy_dmacontroller_rx_reset(struct b43legacy_wldev *dev,
 485                                             u16 mmio_base,
 486                                             enum b43legacy_dmatype type)
 487 {
 488         int i;
 489         u32 value;
 490         u16 offset;
 491
 492         might_sleep();
 493
 494         offset = (type == B43legacy_DMA_64BIT) ?
 495                  B43legacy_DMA64_RXCTL : B43legacy_DMA32_RXCTL;
 496         b43legacy_write32(dev, mmio_base + offset, 0);
 497         for (i = 0; i < 10; i++) {
 498                 offset = (type == B43legacy_DMA_64BIT) ?
 499                          B43legacy_DMA64_RXSTATUS : B43legacy_DMA32_RXSTATUS;
 500                 value = b43legacy_read32(dev, mmio_base + offset);
 501                 if (type == B43legacy_DMA_64BIT) {
 502                         value &= B43legacy_DMA64_RXSTAT;
 503                         if (value == B43legacy_DMA64_RXSTAT_DISABLED) {
 504                                 i = -1;
 505                                 break;
 506                         }
 507                 } else {
 508                         value &= B43legacy_DMA32_RXSTATE;
 509                         if (value == B43legacy_DMA32_RXSTAT_DISABLED) {
 510                                 i = -1;
 511                                 break;
 512                         }
 513                 }
 514                 msleep(1);
 515         }
 516         if (i != -1) {
 517                 b43legacyerr(dev->wl, "DMA RX reset timed out\n");
 518                 return -ENODEV;
 519         }
 520
 521         return 0;
 522 }
 523
 524 /* Reset the RX DMA channel */
 525 static int b43legacy_dmacontroller_tx_reset(struct b43legacy_wldev *dev,
 526                                             u16 mmio_base,
 527                                             enum b43legacy_dmatype type)
 528 {
 529         int i;
 530         u32 value;
 531         u16 offset;
 532
 533         might_sleep();
 534
 535         for (i = 0; i < 10; i++) {
 536                 offset = (type == B43legacy_DMA_64BIT) ?
 537                          B43legacy_DMA64_TXSTATUS : B43legacy_DMA32_TXSTATUS;
 538                 value = b43legacy_read32(dev, mmio_base + offset);
 539                 if (type == B43legacy_DMA_64BIT) {
 540                         value &= B43legacy_DMA64_TXSTAT;
 541                         if (value == B43legacy_DMA64_TXSTAT_DISABLED ||
 542                             value == B43legacy_DMA64_TXSTAT_IDLEWAIT ||
 543                             value == B43legacy_DMA64_TXSTAT_STOPPED)
 544                                 break;
 545                 } else {
 546                         value &= B43legacy_DMA32_TXSTATE;
 547                         if (value == B43legacy_DMA32_TXSTAT_DISABLED ||
 548                             value == B43legacy_DMA32_TXSTAT_IDLEWAIT ||
 549                             value == B43legacy_DMA32_TXSTAT_STOPPED)
 550                                 break;
 551                 }
 552                 msleep(1);
 553         }
 554         offset = (type == B43legacy_DMA_64BIT) ? B43legacy_DMA64_TXCTL :
 555                                                  B43legacy_DMA32_TXCTL;
 556         b43legacy_write32(dev, mmio_base + offset, 0);
 557         for (i = 0; i < 10; i++) {
 558                 offset = (type == B43legacy_DMA_64BIT) ?
 559                          B43legacy_DMA64_TXSTATUS : B43legacy_DMA32_TXSTATUS;
 560                 value = b43legacy_read32(dev, mmio_base + offset);
 561                 if (type == B43legacy_DMA_64BIT) {
 562                         value &= B43legacy_DMA64_TXSTAT;
 563                         if (value == B43legacy_DMA64_TXSTAT_DISABLED) {
 564                                 i = -1;
 565                                 break;
 566                         }
 567                 } else {
 568                         value &= B43legacy_DMA32_TXSTATE;
 569                         if (value == B43legacy_DMA32_TXSTAT_DISABLED) {
 570                                 i = -1;
 571                                 break;
 572                         }
 573                 }
 574                 msleep(1);
 575         }
 576         if (i != -1) {
 577                 b43legacyerr(dev->wl, "DMA TX reset timed out\n");
 578                 return -ENODEV;
 579         }
 580         /* ensure the reset is completed. */
 581         msleep(1);
 582
 583         return 0;
 584 }
 585
 586 /* Check if a DMA mapping address is invalid. */
 587 static bool b43legacy_dma_mapping_error(struct b43legacy_dmaring *ring,
 588                                          dma_addr_t addr,
 589                                          size_t buffersize,
 590                                          bool dma_to_device)
 591 {
 592         if (unlikely(ssb_dma_mapping_error(ring->dev->dev, addr)))
 593                 return 1;
 594
 595         switch (ring->type) {
 596         case B43legacy_DMA_30BIT:
 597                 if ((u64)addr + buffersize > (1ULL << 30))
 598                         goto address_error;
 599                 break;
 600         case B43legacy_DMA_32BIT:
 601                 if ((u64)addr + buffersize > (1ULL << 32))
 602                         goto address_error;
 603                 break;
 604         case B43legacy_DMA_64BIT:
 605                 /* Currently we can't have addresses beyond 64 bits in the kernel. */
 606                 break;
 607         }
 608
 609         /* The address is OK. */
 610         return 0;
 611
 612 address_error:
 613         /* We can't support this address. Unmap it again. */
 614         unmap_descbuffer(ring, addr, buffersize, dma_to_device);
 615
 616         return 1;
 617 }
 618
 619 static int setup_rx_descbuffer(struct b43legacy_dmaring *ring,
 620                                struct b43legacy_dmadesc_generic *desc,
 621                                struct b43legacy_dmadesc_meta *meta,
 622                                gfp_t gfp_flags)
 623 {
 624         struct b43legacy_rxhdr_fw3 *rxhdr;
 625         struct b43legacy_hwtxstatus *txstat;
 626         dma_addr_t dmaaddr;
 627         struct sk_buff *skb;
 628
 629         B43legacy_WARN_ON(ring->tx);
 630
 631         skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 632         if (unlikely(!skb))
 633                 return -ENOMEM;
 634         dmaaddr = map_descbuffer(ring, skb->data,
 635                                  ring->rx_buffersize, 0);
 636         if (b43legacy_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 637                 /* ugh. try to realloc in zone_dma */
 638                 gfp_flags |= GFP_DMA;
 639
 640                 dev_kfree_skb_any(skb);
 641
 642                 skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 643                 if (unlikely(!skb))
 644                         return -ENOMEM;
 645                 dmaaddr = map_descbuffer(ring, skb->data,
 646                                          ring->rx_buffersize, 0);
 647         }
 648
 649         if (b43legacy_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 650                 dev_kfree_skb_any(skb);
 651                 return -EIO;
 652         }
 653
 654         meta->skb = skb;
 655         meta->dmaaddr = dmaaddr;
 656         ring->ops->fill_descriptor(ring, desc, dmaaddr,
 657                                    ring->rx_buffersize, 0, 0, 0);
 658
 659         rxhdr = (struct b43legacy_rxhdr_fw3 *)(skb->data);
 660         rxhdr->frame_len = 0;
 661         txstat = (struct b43legacy_hwtxstatus *)(skb->data);
 662         txstat->cookie = 0;
 663
 664         return 0;
 665 }
 666
 667 /* Allocate the initial descbuffers.
 668  * This is used for an RX ring only.
 669  */
 670 static int alloc_initial_descbuffers(struct b43legacy_dmaring *ring)
 671 {
 672         int i;
 673         int err = -ENOMEM;
 674         struct b43legacy_dmadesc_generic *desc;
 675         struct b43legacy_dmadesc_meta *meta;
 676
 677         for (i = 0; i < ring->nr_slots; i++) {
 678                 desc = ring->ops->idx2desc(ring, i, &meta);
 679
 680                 err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
 681                 if (err) {
 682                         b43legacyerr(ring->dev->wl,
 683                                "Failed to allocate initial descbuffers\n");
 684                         goto err_unwind;
 685                 }
 686         }
 687         mb(); /* all descbuffer setup before next line */
 688         ring->used_slots = ring->nr_slots;
 689         err = 0;
 690 out:
 691         return err;
 692
 693 err_unwind:
 694         for (i--; i >= 0; i--) {
 695                 desc = ring->ops->idx2desc(ring, i, &meta);
 696
 697                 unmap_descbuffer(ring, meta->dmaaddr, ring->rx_buffersize, 0);
 698                 dev_kfree_skb(meta->skb);
 699         }
 700         goto out;
 701 }
 702
 703 /* Do initial setup of the DMA controller.
 704  * Reset the controller, write the ring busaddress
 705  * and switch the "enable" bit on.
 706  */
 707 static int dmacontroller_setup(struct b43legacy_dmaring *ring)
 708 {
 709         int err = 0;
 710         u32 value;
 711         u32 addrext;
 712         u32 trans = ssb_dma_translation(ring->dev->dev);
 713
 714         if (ring->tx) {
 715                 if (ring->type == B43legacy_DMA_64BIT) {
 716                         u64 ringbase = (u64)(ring->dmabase);
 717
 718                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 719                                   >> SSB_DMA_TRANSLATION_SHIFT;
 720                         value = B43legacy_DMA64_TXENABLE;
 721                         value |= (addrext << B43legacy_DMA64_TXADDREXT_SHIFT)
 722                                 & B43legacy_DMA64_TXADDREXT_MASK;
 723                         b43legacy_dma_write(ring, B43legacy_DMA64_TXCTL,
 724                                             value);
 725                         b43legacy_dma_write(ring, B43legacy_DMA64_TXRINGLO,
 726                                             (ringbase & 0xFFFFFFFF));
 727                         b43legacy_dma_write(ring, B43legacy_DMA64_TXRINGHI,
 728                                             ((ringbase >> 32)
 729                                             & ~SSB_DMA_TRANSLATION_MASK)
 730                                             | trans);
 731                 } else {
 732                         u32 ringbase = (u32)(ring->dmabase);
 733
 734                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 735                                   >> SSB_DMA_TRANSLATION_SHIFT;
 736                         value = B43legacy_DMA32_TXENABLE;
 737                         value |= (addrext << B43legacy_DMA32_TXADDREXT_SHIFT)
 738                                 & B43legacy_DMA32_TXADDREXT_MASK;
 739                         b43legacy_dma_write(ring, B43legacy_DMA32_TXCTL,
 740                                             value);
 741                         b43legacy_dma_write(ring, B43legacy_DMA32_TXRING,
 742                                             (ringbase &
 743                                             ~SSB_DMA_TRANSLATION_MASK)
 744                                             | trans);
 745                 }
 746         } else {
 747                 err = alloc_initial_descbuffers(ring);
 748                 if (err)
 749                         goto out;
 750                 if (ring->type == B43legacy_DMA_64BIT) {
 751                         u64 ringbase = (u64)(ring->dmabase);
 752
 753                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 754                                   >> SSB_DMA_TRANSLATION_SHIFT;
 755                         value = (ring->frameoffset <<
 756                                  B43legacy_DMA64_RXFROFF_SHIFT);
 757                         value |= B43legacy_DMA64_RXENABLE;
 758                         value |= (addrext << B43legacy_DMA64_RXADDREXT_SHIFT)
 759                                 & B43legacy_DMA64_RXADDREXT_MASK;
 760                         b43legacy_dma_write(ring, B43legacy_DMA64_RXCTL,
 761                                             value);
 762                         b43legacy_dma_write(ring, B43legacy_DMA64_RXRINGLO,
 763                                             (ringbase & 0xFFFFFFFF));
 764                         b43legacy_dma_write(ring, B43legacy_DMA64_RXRINGHI,
 765                                             ((ringbase >> 32) &
 766                                             ~SSB_DMA_TRANSLATION_MASK) |
 767                                             trans);
 768                         b43legacy_dma_write(ring, B43legacy_DMA64_RXINDEX,
 769                                             200);
 770                 } else {
 771                         u32 ringbase = (u32)(ring->dmabase);
 772
 773                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 774                                   >> SSB_DMA_TRANSLATION_SHIFT;
 775                         value = (ring->frameoffset <<
 776                                  B43legacy_DMA32_RXFROFF_SHIFT);
 777                         value |= B43legacy_DMA32_RXENABLE;
 778                         value |= (addrext <<
 779                                  B43legacy_DMA32_RXADDREXT_SHIFT)
 780                                  & B43legacy_DMA32_RXADDREXT_MASK;
 781                         b43legacy_dma_write(ring, B43legacy_DMA32_RXCTL,
 782                                             value);
 783                         b43legacy_dma_write(ring, B43legacy_DMA32_RXRING,
 784                                             (ringbase &
 785                                             ~SSB_DMA_TRANSLATION_MASK)
 786                                             | trans);
 787                         b43legacy_dma_write(ring, B43legacy_DMA32_RXINDEX,
 788                                             200);
 789                 }
 790         }
 791
 792 out:
 793         return err;
 794 }
 795
 796 /* Shutdown the DMA controller. */
 797 static void dmacontroller_cleanup(struct b43legacy_dmaring *ring)
 798 {
 799         if (ring->tx) {
 800                 b43legacy_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
 801                                                  ring->type);
 802                 if (ring->type == B43legacy_DMA_64BIT) {
 803                         b43legacy_dma_write(ring, B43legacy_DMA64_TXRINGLO, 0);
 804                         b43legacy_dma_write(ring, B43legacy_DMA64_TXRINGHI, 0);
 805                 } else
 806                         b43legacy_dma_write(ring, B43legacy_DMA32_TXRING, 0);
 807         } else {
 808                 b43legacy_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
 809                                                  ring->type);
 810                 if (ring->type == B43legacy_DMA_64BIT) {
 811                         b43legacy_dma_write(ring, B43legacy_DMA64_RXRINGLO, 0);
 812                         b43legacy_dma_write(ring, B43legacy_DMA64_RXRINGHI, 0);
 813                 } else
 814                         b43legacy_dma_write(ring, B43legacy_DMA32_RXRING, 0);
 815         }
 816 }
 817
 818 static void free_all_descbuffers(struct b43legacy_dmaring *ring)
 819 {
 820         struct b43legacy_dmadesc_generic *desc;
 821         struct b43legacy_dmadesc_meta *meta;
 822         int i;
 823
 824         if (!ring->used_slots)
 825                 return;
 826         for (i = 0; i < ring->nr_slots; i++) {
 827                 desc = ring->ops->idx2desc(ring, i, &meta);
 828
 829                 if (!meta->skb) {
 830                         B43legacy_WARN_ON(!ring->tx);
 831                         continue;
 832                 }
 833                 if (ring->tx)
 834                         unmap_descbuffer(ring, meta->dmaaddr,
 835                                          meta->skb->len, 1);
 836                 else
 837                         unmap_descbuffer(ring, meta->dmaaddr,
 838                                          ring->rx_buffersize, 0);
 839                 free_descriptor_buffer(ring, meta, 0);
 840         }
 841 }
 842
 843 static u64 supported_dma_mask(struct b43legacy_wldev *dev)
 844 {
 845         u32 tmp;
 846         u16 mmio_base;
 847
 848         tmp = b43legacy_read32(dev, SSB_TMSHIGH);
 849         if (tmp & SSB_TMSHIGH_DMA64)
 850                 return DMA_BIT_MASK(64);
 851         mmio_base = b43legacy_dmacontroller_base(0, 0);
 852         b43legacy_write32(dev,
 853                         mmio_base + B43legacy_DMA32_TXCTL,
 854                         B43legacy_DMA32_TXADDREXT_MASK);
 855         tmp = b43legacy_read32(dev, mmio_base +
 856                                B43legacy_DMA32_TXCTL);
 857         if (tmp & B43legacy_DMA32_TXADDREXT_MASK)
 858                 return DMA_BIT_MASK(32);
 859
 860         return DMA_BIT_MASK(30);
 861 }
 862
 863 static enum b43legacy_dmatype dma_mask_to_engine_type(u64 dmamask)
 864 {
 865         if (dmamask == DMA_BIT_MASK(30))
 866                 return B43legacy_DMA_30BIT;
 867         if (dmamask == DMA_BIT_MASK(32))
 868                 return B43legacy_DMA_32BIT;
 869         if (dmamask == DMA_BIT_MASK(64))
 870                 return B43legacy_DMA_64BIT;
 871         B43legacy_WARN_ON(1);
 872         return B43legacy_DMA_30BIT;
 873 }
 874
 875 /* Main initialization function. */
 876 static
 877 struct b43legacy_dmaring *b43legacy_setup_dmaring(struct b43legacy_wldev *dev,
 878                                                   int controller_index,
 879                                                   int for_tx,
 880                                                   enum b43legacy_dmatype type)
 881 {
 882         struct b43legacy_dmaring *ring;
 883         int err;
 884         int nr_slots;
 885         dma_addr_t dma_test;
 886
 887         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 888         if (!ring)
 889                 goto out;
 890         ring->type = type;
 891         ring->dev = dev;
 892
 893         nr_slots = B43legacy_RXRING_SLOTS;
 894         if (for_tx)
 895                 nr_slots = B43legacy_TXRING_SLOTS;
 896
 897         ring->meta = kcalloc(nr_slots, sizeof(struct b43legacy_dmadesc_meta),
 898                              GFP_KERNEL);
 899         if (!ring->meta)
 900                 goto err_kfree_ring;
 901         if (for_tx) {
 902                 ring->txhdr_cache = kcalloc(nr_slots,
 903                                         sizeof(struct b43legacy_txhdr_fw3),
 904                                         GFP_KERNEL);
 905                 if (!ring->txhdr_cache)
 906                         goto err_kfree_meta;
 907
 908                 /* test for ability to dma to txhdr_cache */
 909                 dma_test = ssb_dma_map_single(dev->dev, ring->txhdr_cache,
 910                                               sizeof(struct b43legacy_txhdr_fw3),
 911                                               DMA_TO_DEVICE);
 912
 913                 if (b43legacy_dma_mapping_error(ring, dma_test,
 914                                         sizeof(struct b43legacy_txhdr_fw3), 1)) {
 915                         /* ugh realloc */
 916                         kfree(ring->txhdr_cache);
 917                         ring->txhdr_cache = kcalloc(nr_slots,
 918                                         sizeof(struct b43legacy_txhdr_fw3),
 919                                         GFP_KERNEL | GFP_DMA);
 920                         if (!ring->txhdr_cache)
 921                                 goto err_kfree_meta;
 922
 923                         dma_test = ssb_dma_map_single(dev->dev,
 924                                         ring->txhdr_cache,
 925                                         sizeof(struct b43legacy_txhdr_fw3),
 926                                         DMA_TO_DEVICE);
 927
 928                         if (b43legacy_dma_mapping_error(ring, dma_test,
 929                                         sizeof(struct b43legacy_txhdr_fw3), 1))
 930                                 goto err_kfree_txhdr_cache;
 931                 }
 932
 933                 ssb_dma_unmap_single(dev->dev, dma_test,
 934                                      sizeof(struct b43legacy_txhdr_fw3),
 935                                      DMA_TO_DEVICE);
 936         }
 937
 938         ring->nr_slots = nr_slots;
 939         ring->mmio_base = b43legacy_dmacontroller_base(type, controller_index);
 940         ring->index = controller_index;
 941         if (type == B43legacy_DMA_64BIT)
 942                 ring->ops = &dma64_ops;
 943         else
 944                 ring->ops = &dma32_ops;
 945         if (for_tx) {
 946                 ring->tx = 1;
 947                 ring->current_slot = -1;
 948         } else {
 949                 if (ring->index == 0) {
 950                         ring->rx_buffersize = B43legacy_DMA0_RX_BUFFERSIZE;
 951                         ring->frameoffset = B43legacy_DMA0_RX_FRAMEOFFSET;
 952                 } else if (ring->index == 3) {
 953                         ring->rx_buffersize = B43legacy_DMA3_RX_BUFFERSIZE;
 954                         ring->frameoffset = B43legacy_DMA3_RX_FRAMEOFFSET;
 955                 } else
 956                         B43legacy_WARN_ON(1);
 957         }
 958         spin_lock_init(&ring->lock);
 959 #ifdef CONFIG_B43LEGACY_DEBUG
 960         ring->last_injected_overflow = jiffies;
 961 #endif
 962
 963         err = alloc_ringmemory(ring);
 964         if (err)
 965                 goto err_kfree_txhdr_cache;
 966         err = dmacontroller_setup(ring);
 967         if (err)
 968                 goto err_free_ringmemory;
 969
 970 out:
 971         return ring;
 972
 973 err_free_ringmemory:
 974         free_ringmemory(ring);
 975 err_kfree_txhdr_cache:
 976         kfree(ring->txhdr_cache);
 977 err_kfree_meta:
 978         kfree(ring->meta);
 979 err_kfree_ring:
 980         kfree(ring);
 981         ring = NULL;
 982         goto out;
 983 }
 984
 985 /* Main cleanup function. */
 986 static void b43legacy_destroy_dmaring(struct b43legacy_dmaring *ring)
 987 {
 988         if (!ring)
 989                 return;
 990
 991         b43legacydbg(ring->dev->wl, "DMA-%u 0x%04X (%s) max used slots:"
 992                      " %d/%d\n", (unsigned int)(ring->type), ring->mmio_base,
 993                      (ring->tx) ? "TX" : "RX", ring->max_used_slots,
 994                      ring->nr_slots);
 995         /* Device IRQs are disabled prior entering this function,
 996          * so no need to take care of concurrency with rx handler stuff.
 997          */
 998         dmacontroller_cleanup(ring);
 999         free_all_descbuffers(ring);
1000         free_ringmemory(ring);
1001
1002         kfree(ring->txhdr_cache);
1003         kfree(ring->meta);
1004         kfree(ring);
1005 }
1006
1007 void b43legacy_dma_free(struct b43legacy_wldev *dev)
1008 {
1009         struct b43legacy_dma *dma;
1010
1011         if (b43legacy_using_pio(dev))
1012                 return;
1013         dma = &dev->dma;
1014
1015         b43legacy_destroy_dmaring(dma->rx_ring3);
1016         dma->rx_ring3 = NULL;
1017         b43legacy_destroy_dmaring(dma->rx_ring0);
1018         dma->rx_ring0 = NULL;
1019
1020         b43legacy_destroy_dmaring(dma->tx_ring5);
1021         dma->tx_ring5 = NULL;
1022         b43legacy_destroy_dmaring(dma->tx_ring4);
1023         dma->tx_ring4 = NULL;
1024         b43legacy_destroy_dmaring(dma->tx_ring3);
1025         dma->tx_ring3 = NULL;
1026         b43legacy_destroy_dmaring(dma->tx_ring2);
1027         dma->tx_ring2 = NULL;
1028         b43legacy_destroy_dmaring(dma->tx_ring1);
1029         dma->tx_ring1 = NULL;
1030         b43legacy_destroy_dmaring(dma->tx_ring0);
1031         dma->tx_ring0 = NULL;
1032 }
1033
1034 static int b43legacy_dma_set_mask(struct b43legacy_wldev *dev, u64 mask)
1035 {
1036         u64 orig_mask = mask;
1037         bool fallback = 0;
1038         int err;
1039
1040         /* Try to set the DMA mask. If it fails, try falling back to a
1041          * lower mask, as we can always also support a lower one. */
1042         while (1) {
1043                 err = ssb_dma_set_mask(dev->dev, mask);
1044                 if (!err)
1045                         break;
1046                 if (mask == DMA_BIT_MASK(64)) {
1047                         mask = DMA_BIT_MASK(32);
1048                         fallback = 1;
1049                         continue;
1050                 }
1051                 if (mask == DMA_BIT_MASK(32)) {
1052                         mask = DMA_BIT_MASK(30);
1053                         fallback = 1;
1054                         continue;
1055                 }
1056                 b43legacyerr(dev->wl, "The machine/kernel does not support "
1057                        "the required %u-bit DMA mask\n",
1058                        (unsigned int)dma_mask_to_engine_type(orig_mask));
1059                 return -EOPNOTSUPP;
1060         }
1061         if (fallback) {
1062                 b43legacyinfo(dev->wl, "DMA mask fallback from %u-bit to %u-"
1063                         "bit\n",
1064                         (unsigned int)dma_mask_to_engine_type(orig_mask),
1065                         (unsigned int)dma_mask_to_engine_type(mask));
1066         }
1067
1068         return 0;
1069 }
1070
1071 int b43legacy_dma_init(struct b43legacy_wldev *dev)
1072 {
1073         struct b43legacy_dma *dma = &dev->dma;
1074         struct b43legacy_dmaring *ring;
1075         int err;
1076         u64 dmamask;
1077         enum b43legacy_dmatype type;
1078
1079         dmamask = supported_dma_mask(dev);
1080         type = dma_mask_to_engine_type(dmamask);
1081         err = b43legacy_dma_set_mask(dev, dmamask);
1082         if (err) {
1083 #ifdef CONFIG_B43LEGACY_PIO
1084                 b43legacywarn(dev->wl, "DMA for this device not supported. "
1085                         "Falling back to PIO\n");
1086                 dev->__using_pio = 1;
1087                 return -EAGAIN;
1088 #else
1089                 b43legacyerr(dev->wl, "DMA for this device not supported and "
1090                        "no PIO support compiled in\n");
1091                 return -EOPNOTSUPP;
1092 #endif
1093         }
1094
1095         err = -ENOMEM;
1096         /* setup TX DMA channels. */
1097         ring = b43legacy_setup_dmaring(dev, 0, 1, type);
1098         if (!ring)
1099                 goto out;
1100         dma->tx_ring0 = ring;
1101
1102         ring = b43legacy_setup_dmaring(dev, 1, 1, type);
1103         if (!ring)
1104                 goto err_destroy_tx0;
1105         dma->tx_ring1 = ring;
1106
1107         ring = b43legacy_setup_dmaring(dev, 2, 1, type);
1108         if (!ring)
1109                 goto err_destroy_tx1;
1110         dma->tx_ring2 = ring;
1111
1112         ring = b43legacy_setup_dmaring(dev, 3, 1, type);
1113         if (!ring)
1114                 goto err_destroy_tx2;
1115         dma->tx_ring3 = ring;
1116
1117         ring = b43legacy_setup_dmaring(dev, 4, 1, type);
1118         if (!ring)
1119                 goto err_destroy_tx3;
1120         dma->tx_ring4 = ring;
1121
1122         ring = b43legacy_setup_dmaring(dev, 5, 1, type);
1123         if (!ring)
1124                 goto err_destroy_tx4;
1125         dma->tx_ring5 = ring;
1126
1127         /* setup RX DMA channels. */
1128         ring = b43legacy_setup_dmaring(dev, 0, 0, type);
1129         if (!ring)
1130                 goto err_destroy_tx5;
1131         dma->rx_ring0 = ring;
1132
1133         if (dev->dev->id.revision < 5) {
1134                 ring = b43legacy_setup_dmaring(dev, 3, 0, type);
1135                 if (!ring)
1136                         goto err_destroy_rx0;
1137                 dma->rx_ring3 = ring;
1138         }
1139
1140         b43legacydbg(dev->wl, "%u-bit DMA initialized\n", (unsigned int)type);
1141         err = 0;
1142 out:
1143         return err;
1144
1145 err_destroy_rx0:
1146         b43legacy_destroy_dmaring(dma->rx_ring0);
1147         dma->rx_ring0 = NULL;
1148 err_destroy_tx5:
1149         b43legacy_destroy_dmaring(dma->tx_ring5);
1150         dma->tx_ring5 = NULL;
1151 err_destroy_tx4:
1152         b43legacy_destroy_dmaring(dma->tx_ring4);
1153         dma->tx_ring4 = NULL;
1154 err_destroy_tx3:
1155         b43legacy_destroy_dmaring(dma->tx_ring3);
1156         dma->tx_ring3 = NULL;
1157 err_destroy_tx2:
1158         b43legacy_destroy_dmaring(dma->tx_ring2);
1159         dma->tx_ring2 = NULL;
1160 err_destroy_tx1:
1161         b43legacy_destroy_dmaring(dma->tx_ring1);
1162         dma->tx_ring1 = NULL;
1163 err_destroy_tx0:
1164         b43legacy_destroy_dmaring(dma->tx_ring0);
1165         dma->tx_ring0 = NULL;
1166         goto out;
1167 }
1168
1169 /* Generate a cookie for the TX header. */
1170 static u16 generate_cookie(struct b43legacy_dmaring *ring,
1171                            int slot)
1172 {
1173         u16 cookie = 0x1000;
1174
1175         /* Use the upper 4 bits of the cookie as
1176          * DMA controller ID and store the slot number
1177          * in the lower 12 bits.
1178          * Note that the cookie must never be 0, as this
1179          * is a special value used in RX path.
1180          */
1181         switch (ring->index) {
1182         case 0:
1183                 cookie = 0xA000;
1184                 break;
1185         case 1:
1186                 cookie = 0xB000;
1187                 break;
1188         case 2:
1189                 cookie = 0xC000;
1190                 break;
1191         case 3:
1192                 cookie = 0xD000;
1193                 break;
1194         case 4:
1195                 cookie = 0xE000;
1196                 break;
1197         case 5:
1198                 cookie = 0xF000;
1199                 break;
1200         }
1201         B43legacy_WARN_ON(!(((u16)slot & 0xF000) == 0x0000));
1202         cookie |= (u16)slot;
1203
1204         return cookie;
1205 }
1206
1207 /* Inspect a cookie and find out to which controller/slot it belongs. */
1208 static
1209 struct b43legacy_dmaring *parse_cookie(struct b43legacy_wldev *dev,
1210                                       u16 cookie, int *slot)
1211 {
1212         struct b43legacy_dma *dma = &dev->dma;
1213         struct b43legacy_dmaring *ring = NULL;
1214
1215         switch (cookie & 0xF000) {
1216         case 0xA000:
1217                 ring = dma->tx_ring0;
1218                 break;
1219         case 0xB000:
1220                 ring = dma->tx_ring1;
1221                 break;
1222         case 0xC000:
1223                 ring = dma->tx_ring2;
1224                 break;
1225         case 0xD000:
1226                 ring = dma->tx_ring3;
1227                 break;
1228         case 0xE000:
1229                 ring = dma->tx_ring4;
1230                 break;
1231         case 0xF000:
1232                 ring = dma->tx_ring5;
1233                 break;
1234         default:
1235                 B43legacy_WARN_ON(1);
1236         }
1237         *slot = (cookie & 0x0FFF);
1238         B43legacy_WARN_ON(!(ring && *slot >= 0 && *slot < ring->nr_slots));
1239
1240         return ring;
1241 }
1242
1243 static int dma_tx_fragment(struct b43legacy_dmaring *ring,
1244                             struct sk_buff **in_skb)
1245 {
1246         struct sk_buff *skb = *in_skb;
1247         const struct b43legacy_dma_ops *ops = ring->ops;
1248         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1249         u8 *header;
1250         int slot, old_top_slot, old_used_slots;
1251         int err;
1252         struct b43legacy_dmadesc_generic *desc;
1253         struct b43legacy_dmadesc_meta *meta;
1254         struct b43legacy_dmadesc_meta *meta_hdr;
1255         struct sk_buff *bounce_skb;
1256
1257 #define SLOTS_PER_PACKET  2
1258         B43legacy_WARN_ON(skb_shinfo(skb)->nr_frags != 0);
1259
1260         old_top_slot = ring->current_slot;
1261         old_used_slots = ring->used_slots;
1262
1263         /* Get a slot for the header. */
1264         slot = request_slot(ring);
1265         desc = ops->idx2desc(ring, slot, &meta_hdr);
1266         memset(meta_hdr, 0, sizeof(*meta_hdr));
1267
1268         header = &(ring->txhdr_cache[slot * sizeof(
1269                                struct b43legacy_txhdr_fw3)]);
1270         err = b43legacy_generate_txhdr(ring->dev, header,
1271                                  skb->data, skb->len, info,
1272                                  generate_cookie(ring, slot));
1273         if (unlikely(err)) {
1274                 ring->current_slot = old_top_slot;
1275                 ring->used_slots = old_used_slots;
1276                 return err;
1277         }
1278
1279         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1280                                            sizeof(struct b43legacy_txhdr_fw3), 1);
1281         if (b43legacy_dma_mapping_error(ring, meta_hdr->dmaaddr,
1282                                         sizeof(struct b43legacy_txhdr_fw3), 1)) {
1283                 ring->current_slot = old_top_slot;
1284                 ring->used_slots = old_used_slots;
1285                 return -EIO;
1286         }
1287         ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1288                              sizeof(struct b43legacy_txhdr_fw3), 1, 0, 0);
1289
1290         /* Get a slot for the payload. */
1291         slot = request_slot(ring);
1292         desc = ops->idx2desc(ring, slot, &meta);
1293         memset(meta, 0, sizeof(*meta));
1294
1295         meta->skb = skb;
1296         meta->is_last_fragment = 1;
1297
1298         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1299         /* create a bounce buffer in zone_dma on mapping failure. */
1300         if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1301                 bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
1302                 if (!bounce_skb) {
1303                         ring->current_slot = old_top_slot;
1304                         ring->used_slots = old_used_slots;
1305                         err = -ENOMEM;
1306                         goto out_unmap_hdr;
1307                 }
1308
1309                 memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
1310                 memcpy(bounce_skb->cb, skb->cb, sizeof(skb->cb));
1311                 bounce_skb->dev = skb->dev;
1312                 skb_set_queue_mapping(bounce_skb, skb_get_queue_mapping(skb));
1313                 info = IEEE80211_SKB_CB(bounce_skb);
1314
1315                 dev_kfree_skb_any(skb);
1316                 skb = bounce_skb;
1317                 *in_skb = bounce_skb;
1318                 meta->skb = skb;
1319                 meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1320                 if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1321                         ring->current_slot = old_top_slot;
1322                         ring->used_slots = old_used_slots;
1323                         err = -EIO;
1324                         goto out_free_bounce;
1325                 }
1326         }
1327
1328         ops->fill_descriptor(ring, desc, meta->dmaaddr,
1329                              skb->len, 0, 1, 1);
1330
1331         wmb();  /* previous stuff MUST be done */
1332         /* Now transfer the whole frame. */
1333         ops->poke_tx(ring, next_slot(ring, slot));
1334         return 0;
1335
1336 out_free_bounce:
1337         dev_kfree_skb_any(skb);
1338 out_unmap_hdr:
1339         unmap_descbuffer(ring, meta_hdr->dmaaddr,
1340                          sizeof(struct b43legacy_txhdr_fw3), 1);
1341         return err;
1342 }
1343
1344 static inline
1345 int should_inject_overflow(struct b43legacy_dmaring *ring)
1346 {
1347 #ifdef CONFIG_B43LEGACY_DEBUG
1348         if (unlikely(b43legacy_debug(ring->dev,
1349                                      B43legacy_DBG_DMAOVERFLOW))) {
1350                 /* Check if we should inject another ringbuffer overflow
1351                  * to test handling of this situation in the stack. */
1352                 unsigned long next_overflow;
1353
1354                 next_overflow = ring->last_injected_overflow + HZ;
1355                 if (time_after(jiffies, next_overflow)) {
1356                         ring->last_injected_overflow = jiffies;
1357                         b43legacydbg(ring->dev->wl,
1358                                "Injecting TX ring overflow on "
1359                                "DMA controller %d\n", ring->index);
1360                         return 1;
1361                 }
1362         }
1363 #endif /* CONFIG_B43LEGACY_DEBUG */
1364         return 0;
1365 }
1366
1367 int b43legacy_dma_tx(struct b43legacy_wldev *dev,
1368                      struct sk_buff *skb)
1369 {
1370         struct b43legacy_dmaring *ring;
1371         struct ieee80211_hdr *hdr;
1372         int err = 0;
1373         unsigned long flags;
1374         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1375
1376         ring = priority_to_txring(dev, skb_get_queue_mapping(skb));
1377         spin_lock_irqsave(&ring->lock, flags);
1378         B43legacy_WARN_ON(!ring->tx);
1379
1380         if (unlikely(ring->stopped)) {
1381                 /* We get here only because of a bug in mac80211.
1382                  * Because of a race, one packet may be queued after
1383                  * the queue is stopped, thus we got called when we shouldn't.
1384                  * For now, just refuse the transmit. */
1385                 if (b43legacy_debug(dev, B43legacy_DBG_DMAVERBOSE))
1386                         b43legacyerr(dev->wl, "Packet after queue stopped\n");
1387                 err = -ENOSPC;
1388                 goto out_unlock;
1389         }
1390
1391         if (unlikely(WARN_ON(free_slots(ring) < SLOTS_PER_PACKET))) {
1392                 /* If we get here, we have a real error with the queue
1393                  * full, but queues not stopped. */
1394                 b43legacyerr(dev->wl, "DMA queue overflow\n");
1395                 err = -ENOSPC;
1396                 goto out_unlock;
1397         }
1398
1399         /* dma_tx_fragment might reallocate the skb, so invalidate pointers pointing
1400          * into the skb data or cb now. */
1401         hdr = NULL;
1402         info = NULL;
1403         err = dma_tx_fragment(ring, &skb);
1404         if (unlikely(err == -ENOKEY)) {
1405                 /* Drop this packet, as we don't have the encryption key
1406                  * anymore and must not transmit it unencrypted. */
1407                 dev_kfree_skb_any(skb);
1408                 err = 0;
1409                 goto out_unlock;
1410         }
1411         if (unlikely(err)) {
1412                 b43legacyerr(dev->wl, "DMA tx mapping failure\n");
1413                 goto out_unlock;
1414         }
1415         if ((free_slots(ring) < SLOTS_PER_PACKET) ||
1416             should_inject_overflow(ring)) {
1417                 /* This TX ring is full. */
1418                 ieee80211_stop_queue(dev->wl->hw, txring_to_priority(ring));
1419                 ring->stopped = 1;
1420                 if (b43legacy_debug(dev, B43legacy_DBG_DMAVERBOSE))
1421                         b43legacydbg(dev->wl, "Stopped TX ring %d\n",
1422                                ring->index);
1423         }
1424 out_unlock:
1425         spin_unlock_irqrestore(&ring->lock, flags);
1426
1427         return err;
1428 }
1429
1430 void b43legacy_dma_handle_txstatus(struct b43legacy_wldev *dev,
1431                                  const struct b43legacy_txstatus *status)
1432 {
1433         const struct b43legacy_dma_ops *ops;
1434         struct b43legacy_dmaring *ring;
1435         struct b43legacy_dmadesc_generic *desc;
1436         struct b43legacy_dmadesc_meta *meta;
1437         int retry_limit;
1438         int slot;
1439
1440         ring = parse_cookie(dev, status->cookie, &slot);
1441         if (unlikely(!ring))
1442                 return;
1443         B43legacy_WARN_ON(!irqs_disabled());
1444         spin_lock(&ring->lock);
1445
1446         B43legacy_WARN_ON(!ring->tx);
1447         ops = ring->ops;
1448         while (1) {
1449                 B43legacy_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
1450                 desc = ops->idx2desc(ring, slot, &meta);
1451
1452                 if (meta->skb)
1453                         unmap_descbuffer(ring, meta->dmaaddr,
1454                                          meta->skb->len, 1);
1455                 else
1456                         unmap_descbuffer(ring, meta->dmaaddr,
1457                                          sizeof(struct b43legacy_txhdr_fw3),
1458                                          1);
1459
1460                 if (meta->is_last_fragment) {
1461                         struct ieee80211_tx_info *info;
1462                         BUG_ON(!meta->skb);
1463                         info = IEEE80211_SKB_CB(meta->skb);
1464
1465                         /* preserve the confiured retry limit before clearing the status
1466                          * The xmit function has overwritten the rc's value with the actual
1467                          * retry limit done by the hardware */
1468                         retry_limit = info->status.rates[0].count;
1469                         ieee80211_tx_info_clear_status(info);
1470
1471                         if (status->acked)
1472                                 info->flags |= IEEE80211_TX_STAT_ACK;
1473
1474                         if (status->rts_count > dev->wl->hw->conf.short_frame_max_tx_count) {
1475                                 /*
1476                                  * If the short retries (RTS, not data frame) have exceeded
1477                                  * the limit, the hw will not have tried the selected rate,
1478                                  * but will have used the fallback rate instead.
1479                                  * Don't let the rate control count attempts for the selected
1480                                  * rate in this case, otherwise the statistics will be off.
1481                                  */
1482                                 info->status.rates[0].count = 0;
1483                                 info->status.rates[1].count = status->frame_count;
1484                         } else {
1485                                 if (status->frame_count > retry_limit) {
1486                                         info->status.rates[0].count = retry_limit;
1487                                         info->status.rates[1].count = status->frame_count -
1488                                                         retry_limit;
1489
1490                                 } else {
1491                                         info->status.rates[0].count = status->frame_count;
1492                                         info->status.rates[1].idx = -1;
1493                                 }
1494                         }
1495
1496                         /* Call back to inform the ieee80211 subsystem about the
1497                          * status of the transmission.
1498                          * Some fields of txstat are already filled in dma_tx().
1499                          */
1500                         ieee80211_tx_status_irqsafe(dev->wl->hw, meta->skb);
1501                         /* skb is freed by ieee80211_tx_status_irqsafe() */
1502                         meta->skb = NULL;
1503                 } else {
1504                         /* No need to call free_descriptor_buffer here, as
1505                          * this is only the txhdr, which is not allocated.
1506                          */
1507                         B43legacy_WARN_ON(meta->skb != NULL);
1508                 }
1509
1510                 /* Everything unmapped and free'd. So it's not used anymore. */
1511                 ring->used_slots--;
1512
1513                 if (meta->is_last_fragment)
1514                         break;
1515                 slot = next_slot(ring, slot);
1516         }
1517         dev->stats.last_tx = jiffies;
1518         if (ring->stopped) {
1519                 B43legacy_WARN_ON(free_slots(ring) < SLOTS_PER_PACKET);
1520                 ieee80211_wake_queue(dev->wl->hw, txring_to_priority(ring));
1521                 ring->stopped = 0;
1522                 if (b43legacy_debug(dev, B43legacy_DBG_DMAVERBOSE))
1523                         b43legacydbg(dev->wl, "Woke up TX ring %d\n",
1524                                ring->index);
1525         }
1526
1527         spin_unlock(&ring->lock);
1528 }
1529
1530 static void dma_rx(struct b43legacy_dmaring *ring,
1531                    int *slot)
1532 {
1533         const struct b43legacy_dma_ops *ops = ring->ops;
1534         struct b43legacy_dmadesc_generic *desc;
1535         struct b43legacy_dmadesc_meta *meta;
1536         struct b43legacy_rxhdr_fw3 *rxhdr;
1537         struct sk_buff *skb;
1538         u16 len;
1539         int err;
1540         dma_addr_t dmaaddr;
1541
1542         desc = ops->idx2desc(ring, *slot, &meta);
1543
1544         sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1545         skb = meta->skb;
1546
1547         if (ring->index == 3) {
1548                 /* We received an xmit status. */
1549                 struct b43legacy_hwtxstatus *hw =
1550                                 (struct b43legacy_hwtxstatus *)skb->data;
1551                 int i = 0;
1552
1553                 while (hw->cookie == 0) {
1554                         if (i > 100)
1555                                 break;
1556                         i++;
1557                         udelay(2);
1558                         barrier();
1559                 }
1560                 b43legacy_handle_hwtxstatus(ring->dev, hw);
1561                 /* recycle the descriptor buffer. */
1562                 sync_descbuffer_for_device(ring, meta->dmaaddr,
1563                                            ring->rx_buffersize);
1564
1565                 return;
1566         }
1567         rxhdr = (struct b43legacy_rxhdr_fw3 *)skb->data;
1568         len = le16_to_cpu(rxhdr->frame_len);
1569         if (len == 0) {
1570                 int i = 0;
1571
1572                 do {
1573                         udelay(2);
1574                         barrier();
1575                         len = le16_to_cpu(rxhdr->frame_len);
1576                 } while (len == 0 && i++ < 5);
1577                 if (unlikely(len == 0)) {
1578                         /* recycle the descriptor buffer. */
1579                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1580                                                    ring->rx_buffersize);
1581                         goto drop;
1582                 }
1583         }
1584         if (unlikely(len > ring->rx_buffersize)) {
1585                 /* The data did not fit into one descriptor buffer
1586                  * and is split over multiple buffers.
1587                  * This should never happen, as we try to allocate buffers
1588                  * big enough. So simply ignore this packet.
1589                  */
1590                 int cnt = 0;
1591                 s32 tmp = len;
1592
1593                 while (1) {
1594                         desc = ops->idx2desc(ring, *slot, &meta);
1595                         /* recycle the descriptor buffer. */
1596                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1597                                                    ring->rx_buffersize);
1598                         *slot = next_slot(ring, *slot);
1599                         cnt++;
1600                         tmp -= ring->rx_buffersize;
1601                         if (tmp <= 0)
1602                                 break;
1603                 }
1604                 b43legacyerr(ring->dev->wl, "DMA RX buffer too small "
1605                        "(len: %u, buffer: %u, nr-dropped: %d)\n",
1606                        len, ring->rx_buffersize, cnt);
1607                 goto drop;
1608         }
1609
1610         dmaaddr = meta->dmaaddr;
1611         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1612         if (unlikely(err)) {
1613                 b43legacydbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer()"
1614                              " failed\n");
1615                 sync_descbuffer_for_device(ring, dmaaddr,
1616                                            ring->rx_buffersize);
1617                 goto drop;
1618         }
1619
1620         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1621         skb_put(skb, len + ring->frameoffset);
1622         skb_pull(skb, ring->frameoffset);
1623
1624         b43legacy_rx(ring->dev, skb, rxhdr);
1625 drop:
1626         return;
1627 }
1628
1629 void b43legacy_dma_rx(struct b43legacy_dmaring *ring)
1630 {
1631         const struct b43legacy_dma_ops *ops = ring->ops;
1632         int slot;
1633         int current_slot;
1634         int used_slots = 0;
1635
1636         B43legacy_WARN_ON(ring->tx);
1637         current_slot = ops->get_current_rxslot(ring);
1638         B43legacy_WARN_ON(!(current_slot >= 0 && current_slot <
1639                            ring->nr_slots));
1640
1641         slot = ring->current_slot;
1642         for (; slot != current_slot; slot = next_slot(ring, slot)) {
1643                 dma_rx(ring, &slot);
1644                 update_max_used_slots(ring, ++used_slots);
1645         }
1646         ops->set_current_rxslot(ring, slot);
1647         ring->current_slot = slot;
1648 }
1649
1650 static void b43legacy_dma_tx_suspend_ring(struct b43legacy_dmaring *ring)
1651 {
1652         unsigned long flags;
1653
1654         spin_lock_irqsave(&ring->lock, flags);
1655         B43legacy_WARN_ON(!ring->tx);
1656         ring->ops->tx_suspend(ring);
1657         spin_unlock_irqrestore(&ring->lock, flags);
1658 }
1659
1660 static void b43legacy_dma_tx_resume_ring(struct b43legacy_dmaring *ring)
1661 {
1662         unsigned long flags;
1663
1664         spin_lock_irqsave(&ring->lock, flags);
1665         B43legacy_WARN_ON(!ring->tx);
1666         ring->ops->tx_resume(ring);
1667         spin_unlock_irqrestore(&ring->lock, flags);
1668 }
1669
1670 void b43legacy_dma_tx_suspend(struct b43legacy_wldev *dev)
1671 {
1672         b43legacy_power_saving_ctl_bits(dev, -1, 1);
1673         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring0);
1674         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring1);
1675         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring2);
1676         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring3);
1677         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring4);
1678         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring5);
1679 }
1680
1681 void b43legacy_dma_tx_resume(struct b43legacy_wldev *dev)
1682 {
1683         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring5);
1684         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring4);
1685         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring3);
1686         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring2);
1687         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring1);
1688         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring0);
1689         b43legacy_power_saving_ctl_bits(dev, -1, -1);
1690 }