git.oblomov.eu Git - linux-2.6/blob - drivers/net/wireless/b43/dma.c

   1 /*
   2
   3   Broadcom B43 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 "b43.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/etherdevice.h>
  41
  42
  43 /* 32bit DMA ops. */
  44 static
  45 struct b43_dmadesc_generic *op32_idx2desc(struct b43_dmaring *ring,
  46                                           int slot,
  47                                           struct b43_dmadesc_meta **meta)
  48 {
  49         struct b43_dmadesc32 *desc;
  50
  51         *meta = &(ring->meta[slot]);
  52         desc = ring->descbase;
  53         desc = &(desc[slot]);
  54
  55         return (struct b43_dmadesc_generic *)desc;
  56 }
  57
  58 static void op32_fill_descriptor(struct b43_dmaring *ring,
  59                                  struct b43_dmadesc_generic *desc,
  60                                  dma_addr_t dmaaddr, u16 bufsize,
  61                                  int start, int end, int irq)
  62 {
  63         struct b43_dmadesc32 *descbase = ring->descbase;
  64         int slot;
  65         u32 ctl;
  66         u32 addr;
  67         u32 addrext;
  68
  69         slot = (int)(&(desc->dma32) - descbase);
  70         B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
  71
  72         addr = (u32) (dmaaddr & ~SSB_DMA_TRANSLATION_MASK);
  73         addrext = (u32) (dmaaddr & SSB_DMA_TRANSLATION_MASK)
  74             >> SSB_DMA_TRANSLATION_SHIFT;
  75         addr |= ssb_dma_translation(ring->dev->dev);
  76         ctl = (bufsize - ring->frameoffset)
  77             & B43_DMA32_DCTL_BYTECNT;
  78         if (slot == ring->nr_slots - 1)
  79                 ctl |= B43_DMA32_DCTL_DTABLEEND;
  80         if (start)
  81                 ctl |= B43_DMA32_DCTL_FRAMESTART;
  82         if (end)
  83                 ctl |= B43_DMA32_DCTL_FRAMEEND;
  84         if (irq)
  85                 ctl |= B43_DMA32_DCTL_IRQ;
  86         ctl |= (addrext << B43_DMA32_DCTL_ADDREXT_SHIFT)
  87             & B43_DMA32_DCTL_ADDREXT_MASK;
  88
  89         desc->dma32.control = cpu_to_le32(ctl);
  90         desc->dma32.address = cpu_to_le32(addr);
  91 }
  92
  93 static void op32_poke_tx(struct b43_dmaring *ring, int slot)
  94 {
  95         b43_dma_write(ring, B43_DMA32_TXINDEX,
  96                       (u32) (slot * sizeof(struct b43_dmadesc32)));
  97 }
  98
  99 static void op32_tx_suspend(struct b43_dmaring *ring)
 100 {
 101         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 102                       | B43_DMA32_TXSUSPEND);
 103 }
 104
 105 static void op32_tx_resume(struct b43_dmaring *ring)
 106 {
 107         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 108                       & ~B43_DMA32_TXSUSPEND);
 109 }
 110
 111 static int op32_get_current_rxslot(struct b43_dmaring *ring)
 112 {
 113         u32 val;
 114
 115         val = b43_dma_read(ring, B43_DMA32_RXSTATUS);
 116         val &= B43_DMA32_RXDPTR;
 117
 118         return (val / sizeof(struct b43_dmadesc32));
 119 }
 120
 121 static void op32_set_current_rxslot(struct b43_dmaring *ring, int slot)
 122 {
 123         b43_dma_write(ring, B43_DMA32_RXINDEX,
 124                       (u32) (slot * sizeof(struct b43_dmadesc32)));
 125 }
 126
 127 static const struct b43_dma_ops dma32_ops = {
 128         .idx2desc = op32_idx2desc,
 129         .fill_descriptor = op32_fill_descriptor,
 130         .poke_tx = op32_poke_tx,
 131         .tx_suspend = op32_tx_suspend,
 132         .tx_resume = op32_tx_resume,
 133         .get_current_rxslot = op32_get_current_rxslot,
 134         .set_current_rxslot = op32_set_current_rxslot,
 135 };
 136
 137 /* 64bit DMA ops. */
 138 static
 139 struct b43_dmadesc_generic *op64_idx2desc(struct b43_dmaring *ring,
 140                                           int slot,
 141                                           struct b43_dmadesc_meta **meta)
 142 {
 143         struct b43_dmadesc64 *desc;
 144
 145         *meta = &(ring->meta[slot]);
 146         desc = ring->descbase;
 147         desc = &(desc[slot]);
 148
 149         return (struct b43_dmadesc_generic *)desc;
 150 }
 151
 152 static void op64_fill_descriptor(struct b43_dmaring *ring,
 153                                  struct b43_dmadesc_generic *desc,
 154                                  dma_addr_t dmaaddr, u16 bufsize,
 155                                  int start, int end, int irq)
 156 {
 157         struct b43_dmadesc64 *descbase = ring->descbase;
 158         int slot;
 159         u32 ctl0 = 0, ctl1 = 0;
 160         u32 addrlo, addrhi;
 161         u32 addrext;
 162
 163         slot = (int)(&(desc->dma64) - descbase);
 164         B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
 165
 166         addrlo = (u32) (dmaaddr & 0xFFFFFFFF);
 167         addrhi = (((u64) dmaaddr >> 32) & ~SSB_DMA_TRANSLATION_MASK);
 168         addrext = (((u64) dmaaddr >> 32) & SSB_DMA_TRANSLATION_MASK)
 169             >> SSB_DMA_TRANSLATION_SHIFT;
 170         addrhi |= (ssb_dma_translation(ring->dev->dev) << 1);
 171         if (slot == ring->nr_slots - 1)
 172                 ctl0 |= B43_DMA64_DCTL0_DTABLEEND;
 173         if (start)
 174                 ctl0 |= B43_DMA64_DCTL0_FRAMESTART;
 175         if (end)
 176                 ctl0 |= B43_DMA64_DCTL0_FRAMEEND;
 177         if (irq)
 178                 ctl0 |= B43_DMA64_DCTL0_IRQ;
 179         ctl1 |= (bufsize - ring->frameoffset)
 180             & B43_DMA64_DCTL1_BYTECNT;
 181         ctl1 |= (addrext << B43_DMA64_DCTL1_ADDREXT_SHIFT)
 182             & B43_DMA64_DCTL1_ADDREXT_MASK;
 183
 184         desc->dma64.control0 = cpu_to_le32(ctl0);
 185         desc->dma64.control1 = cpu_to_le32(ctl1);
 186         desc->dma64.address_low = cpu_to_le32(addrlo);
 187         desc->dma64.address_high = cpu_to_le32(addrhi);
 188 }
 189
 190 static void op64_poke_tx(struct b43_dmaring *ring, int slot)
 191 {
 192         b43_dma_write(ring, B43_DMA64_TXINDEX,
 193                       (u32) (slot * sizeof(struct b43_dmadesc64)));
 194 }
 195
 196 static void op64_tx_suspend(struct b43_dmaring *ring)
 197 {
 198         b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
 199                       | B43_DMA64_TXSUSPEND);
 200 }
 201
 202 static void op64_tx_resume(struct b43_dmaring *ring)
 203 {
 204         b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
 205                       & ~B43_DMA64_TXSUSPEND);
 206 }
 207
 208 static int op64_get_current_rxslot(struct b43_dmaring *ring)
 209 {
 210         u32 val;
 211
 212         val = b43_dma_read(ring, B43_DMA64_RXSTATUS);
 213         val &= B43_DMA64_RXSTATDPTR;
 214
 215         return (val / sizeof(struct b43_dmadesc64));
 216 }
 217
 218 static void op64_set_current_rxslot(struct b43_dmaring *ring, int slot)
 219 {
 220         b43_dma_write(ring, B43_DMA64_RXINDEX,
 221                       (u32) (slot * sizeof(struct b43_dmadesc64)));
 222 }
 223
 224 static const struct b43_dma_ops dma64_ops = {
 225         .idx2desc = op64_idx2desc,
 226         .fill_descriptor = op64_fill_descriptor,
 227         .poke_tx = op64_poke_tx,
 228         .tx_suspend = op64_tx_suspend,
 229         .tx_resume = op64_tx_resume,
 230         .get_current_rxslot = op64_get_current_rxslot,
 231         .set_current_rxslot = op64_set_current_rxslot,
 232 };
 233
 234 static inline int free_slots(struct b43_dmaring *ring)
 235 {
 236         return (ring->nr_slots - ring->used_slots);
 237 }
 238
 239 static inline int next_slot(struct b43_dmaring *ring, int slot)
 240 {
 241         B43_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
 242         if (slot == ring->nr_slots - 1)
 243                 return 0;
 244         return slot + 1;
 245 }
 246
 247 static inline int prev_slot(struct b43_dmaring *ring, int slot)
 248 {
 249         B43_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
 250         if (slot == 0)
 251                 return ring->nr_slots - 1;
 252         return slot - 1;
 253 }
 254
 255 #ifdef CONFIG_B43_DEBUG
 256 static void update_max_used_slots(struct b43_dmaring *ring,
 257                                   int current_used_slots)
 258 {
 259         if (current_used_slots <= ring->max_used_slots)
 260                 return;
 261         ring->max_used_slots = current_used_slots;
 262         if (b43_debug(ring->dev, B43_DBG_DMAVERBOSE)) {
 263                 b43dbg(ring->dev->wl,
 264                        "max_used_slots increased to %d on %s ring %d\n",
 265                        ring->max_used_slots,
 266                        ring->tx ? "TX" : "RX", ring->index);
 267         }
 268 }
 269 #else
 270 static inline
 271     void update_max_used_slots(struct b43_dmaring *ring, int current_used_slots)
 272 {
 273 }
 274 #endif /* DEBUG */
 275
 276 /* Request a slot for usage. */
 277 static inline int request_slot(struct b43_dmaring *ring)
 278 {
 279         int slot;
 280
 281         B43_WARN_ON(!ring->tx);
 282         B43_WARN_ON(ring->stopped);
 283         B43_WARN_ON(free_slots(ring) == 0);
 284
 285         slot = next_slot(ring, ring->current_slot);
 286         ring->current_slot = slot;
 287         ring->used_slots++;
 288
 289         update_max_used_slots(ring, ring->used_slots);
 290
 291         return slot;
 292 }
 293
 294 /* Mac80211-queue to b43-ring mapping */
 295 static struct b43_dmaring *priority_to_txring(struct b43_wldev *dev,
 296                                               int queue_priority)
 297 {
 298         struct b43_dmaring *ring;
 299
 300 /*FIXME: For now we always run on TX-ring-1 */
 301         return dev->dma.tx_ring1;
 302
 303         /* 0 = highest priority */
 304         switch (queue_priority) {
 305         default:
 306                 B43_WARN_ON(1);
 307                 /* fallthrough */
 308         case 0:
 309                 ring = dev->dma.tx_ring3;
 310                 break;
 311         case 1:
 312                 ring = dev->dma.tx_ring2;
 313                 break;
 314         case 2:
 315                 ring = dev->dma.tx_ring1;
 316                 break;
 317         case 3:
 318                 ring = dev->dma.tx_ring0;
 319                 break;
 320         }
 321
 322         return ring;
 323 }
 324
 325 /* b43-ring to mac80211-queue mapping */
 326 static inline int txring_to_priority(struct b43_dmaring *ring)
 327 {
 328         static const u8 idx_to_prio[] = { 3, 2, 1, 0, };
 329         unsigned int index;
 330
 331 /*FIXME: have only one queue, for now */
 332         return 0;
 333
 334         index = ring->index;
 335         if (B43_WARN_ON(index >= ARRAY_SIZE(idx_to_prio)))
 336                 index = 0;
 337         return idx_to_prio[index];
 338 }
 339
 340 static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
 341 {
 342         static const u16 map64[] = {
 343                 B43_MMIO_DMA64_BASE0,
 344                 B43_MMIO_DMA64_BASE1,
 345                 B43_MMIO_DMA64_BASE2,
 346                 B43_MMIO_DMA64_BASE3,
 347                 B43_MMIO_DMA64_BASE4,
 348                 B43_MMIO_DMA64_BASE5,
 349         };
 350         static const u16 map32[] = {
 351                 B43_MMIO_DMA32_BASE0,
 352                 B43_MMIO_DMA32_BASE1,
 353                 B43_MMIO_DMA32_BASE2,
 354                 B43_MMIO_DMA32_BASE3,
 355                 B43_MMIO_DMA32_BASE4,
 356                 B43_MMIO_DMA32_BASE5,
 357         };
 358
 359         if (type == B43_DMA_64BIT) {
 360                 B43_WARN_ON(!(controller_idx >= 0 &&
 361                               controller_idx < ARRAY_SIZE(map64)));
 362                 return map64[controller_idx];
 363         }
 364         B43_WARN_ON(!(controller_idx >= 0 &&
 365                       controller_idx < ARRAY_SIZE(map32)));
 366         return map32[controller_idx];
 367 }
 368
 369 static inline
 370     dma_addr_t map_descbuffer(struct b43_dmaring *ring,
 371                               unsigned char *buf, size_t len, int tx)
 372 {
 373         dma_addr_t dmaaddr;
 374
 375         if (tx) {
 376                 dmaaddr = dma_map_single(ring->dev->dev->dev,
 377                                          buf, len, DMA_TO_DEVICE);
 378         } else {
 379                 dmaaddr = dma_map_single(ring->dev->dev->dev,
 380                                          buf, len, DMA_FROM_DEVICE);
 381         }
 382
 383         return dmaaddr;
 384 }
 385
 386 static inline
 387     void unmap_descbuffer(struct b43_dmaring *ring,
 388                           dma_addr_t addr, size_t len, int tx)
 389 {
 390         if (tx) {
 391                 dma_unmap_single(ring->dev->dev->dev, addr, len, DMA_TO_DEVICE);
 392         } else {
 393                 dma_unmap_single(ring->dev->dev->dev,
 394                                  addr, len, DMA_FROM_DEVICE);
 395         }
 396 }
 397
 398 static inline
 399     void sync_descbuffer_for_cpu(struct b43_dmaring *ring,
 400                                  dma_addr_t addr, size_t len)
 401 {
 402         B43_WARN_ON(ring->tx);
 403         dma_sync_single_for_cpu(ring->dev->dev->dev,
 404                                 addr, len, DMA_FROM_DEVICE);
 405 }
 406
 407 static inline
 408     void sync_descbuffer_for_device(struct b43_dmaring *ring,
 409                                     dma_addr_t addr, size_t len)
 410 {
 411         B43_WARN_ON(ring->tx);
 412         dma_sync_single_for_device(ring->dev->dev->dev,
 413                                    addr, len, DMA_FROM_DEVICE);
 414 }
 415
 416 static inline
 417     void free_descriptor_buffer(struct b43_dmaring *ring,
 418                                 struct b43_dmadesc_meta *meta)
 419 {
 420         if (meta->skb) {
 421                 dev_kfree_skb_any(meta->skb);
 422                 meta->skb = NULL;
 423         }
 424 }
 425
 426 static int alloc_ringmemory(struct b43_dmaring *ring)
 427 {
 428         struct device *dev = ring->dev->dev->dev;
 429         gfp_t flags = GFP_KERNEL;
 430
 431         /* The specs call for 4K buffers for 30- and 32-bit DMA with 4K
 432          * alignment and 8K buffers for 64-bit DMA with 8K alignment. Testing
 433          * has shown that 4K is sufficient for the latter as long as the buffer
 434          * does not cross an 8K boundary.
 435          *
 436          * For unknown reasons - possibly a hardware error - the BCM4311 rev
 437          * 02, which uses 64-bit DMA, needs the ring buffer in very low memory,
 438          * which accounts for the GFP_DMA flag below.
 439          */
 440         if (ring->type == B43_DMA_64BIT)
 441                 flags |= GFP_DMA;
 442         ring->descbase = dma_alloc_coherent(dev, B43_DMA_RINGMEMSIZE,
 443                                             &(ring->dmabase), flags);
 444         if (!ring->descbase) {
 445                 b43err(ring->dev->wl, "DMA ringmemory allocation failed\n");
 446                 return -ENOMEM;
 447         }
 448         memset(ring->descbase, 0, B43_DMA_RINGMEMSIZE);
 449
 450         return 0;
 451 }
 452
 453 static void free_ringmemory(struct b43_dmaring *ring)
 454 {
 455         struct device *dev = ring->dev->dev->dev;
 456
 457         dma_free_coherent(dev, B43_DMA_RINGMEMSIZE,
 458                           ring->descbase, ring->dmabase);
 459 }
 460
 461 /* Reset the RX DMA channel */
 462 static int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base,
 463                                       enum b43_dmatype type)
 464 {
 465         int i;
 466         u32 value;
 467         u16 offset;
 468
 469         might_sleep();
 470
 471         offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
 472         b43_write32(dev, mmio_base + offset, 0);
 473         for (i = 0; i < 10; i++) {
 474                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXSTATUS :
 475                                                    B43_DMA32_RXSTATUS;
 476                 value = b43_read32(dev, mmio_base + offset);
 477                 if (type == B43_DMA_64BIT) {
 478                         value &= B43_DMA64_RXSTAT;
 479                         if (value == B43_DMA64_RXSTAT_DISABLED) {
 480                                 i = -1;
 481                                 break;
 482                         }
 483                 } else {
 484                         value &= B43_DMA32_RXSTATE;
 485                         if (value == B43_DMA32_RXSTAT_DISABLED) {
 486                                 i = -1;
 487                                 break;
 488                         }
 489                 }
 490                 msleep(1);
 491         }
 492         if (i != -1) {
 493                 b43err(dev->wl, "DMA RX reset timed out\n");
 494                 return -ENODEV;
 495         }
 496
 497         return 0;
 498 }
 499
 500 /* Reset the TX DMA channel */
 501 static int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base,
 502                                       enum b43_dmatype type)
 503 {
 504         int i;
 505         u32 value;
 506         u16 offset;
 507
 508         might_sleep();
 509
 510         for (i = 0; i < 10; i++) {
 511                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 512                                                    B43_DMA32_TXSTATUS;
 513                 value = b43_read32(dev, mmio_base + offset);
 514                 if (type == B43_DMA_64BIT) {
 515                         value &= B43_DMA64_TXSTAT;
 516                         if (value == B43_DMA64_TXSTAT_DISABLED ||
 517                             value == B43_DMA64_TXSTAT_IDLEWAIT ||
 518                             value == B43_DMA64_TXSTAT_STOPPED)
 519                                 break;
 520                 } else {
 521                         value &= B43_DMA32_TXSTATE;
 522                         if (value == B43_DMA32_TXSTAT_DISABLED ||
 523                             value == B43_DMA32_TXSTAT_IDLEWAIT ||
 524                             value == B43_DMA32_TXSTAT_STOPPED)
 525                                 break;
 526                 }
 527                 msleep(1);
 528         }
 529         offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
 530         b43_write32(dev, mmio_base + offset, 0);
 531         for (i = 0; i < 10; i++) {
 532                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 533                                                    B43_DMA32_TXSTATUS;
 534                 value = b43_read32(dev, mmio_base + offset);
 535                 if (type == B43_DMA_64BIT) {
 536                         value &= B43_DMA64_TXSTAT;
 537                         if (value == B43_DMA64_TXSTAT_DISABLED) {
 538                                 i = -1;
 539                                 break;
 540                         }
 541                 } else {
 542                         value &= B43_DMA32_TXSTATE;
 543                         if (value == B43_DMA32_TXSTAT_DISABLED) {
 544                                 i = -1;
 545                                 break;
 546                         }
 547                 }
 548                 msleep(1);
 549         }
 550         if (i != -1) {
 551                 b43err(dev->wl, "DMA TX reset timed out\n");
 552                 return -ENODEV;
 553         }
 554         /* ensure the reset is completed. */
 555         msleep(1);
 556
 557         return 0;
 558 }
 559
 560 /* Check if a DMA mapping address is invalid. */
 561 static bool b43_dma_mapping_error(struct b43_dmaring *ring,
 562                                   dma_addr_t addr,
 563                                   size_t buffersize)
 564 {
 565         if (unlikely(dma_mapping_error(addr)))
 566                 return 1;
 567
 568         switch (ring->type) {
 569         case B43_DMA_30BIT:
 570                 if ((u64)addr + buffersize > (1ULL << 30))
 571                         return 1;
 572                 break;
 573         case B43_DMA_32BIT:
 574                 if ((u64)addr + buffersize > (1ULL << 32))
 575                         return 1;
 576                 break;
 577         case B43_DMA_64BIT:
 578                 /* Currently we can't have addresses beyond
 579                  * 64bit in the kernel. */
 580                 break;
 581         }
 582
 583         /* The address is OK. */
 584         return 0;
 585 }
 586
 587 static int setup_rx_descbuffer(struct b43_dmaring *ring,
 588                                struct b43_dmadesc_generic *desc,
 589                                struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
 590 {
 591         struct b43_rxhdr_fw4 *rxhdr;
 592         struct b43_hwtxstatus *txstat;
 593         dma_addr_t dmaaddr;
 594         struct sk_buff *skb;
 595
 596         B43_WARN_ON(ring->tx);
 597
 598         skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 599         if (unlikely(!skb))
 600                 return -ENOMEM;
 601         dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
 602         if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize)) {
 603                 /* ugh. try to realloc in zone_dma */
 604                 gfp_flags |= GFP_DMA;
 605
 606                 dev_kfree_skb_any(skb);
 607
 608                 skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 609                 if (unlikely(!skb))
 610                         return -ENOMEM;
 611                 dmaaddr = map_descbuffer(ring, skb->data,
 612                                          ring->rx_buffersize, 0);
 613         }
 614
 615         if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize)) {
 616                 dev_kfree_skb_any(skb);
 617                 return -EIO;
 618         }
 619
 620         meta->skb = skb;
 621         meta->dmaaddr = dmaaddr;
 622         ring->ops->fill_descriptor(ring, desc, dmaaddr,
 623                                    ring->rx_buffersize, 0, 0, 0);
 624
 625         rxhdr = (struct b43_rxhdr_fw4 *)(skb->data);
 626         rxhdr->frame_len = 0;
 627         txstat = (struct b43_hwtxstatus *)(skb->data);
 628         txstat->cookie = 0;
 629
 630         return 0;
 631 }
 632
 633 /* Allocate the initial descbuffers.
 634  * This is used for an RX ring only.
 635  */
 636 static int alloc_initial_descbuffers(struct b43_dmaring *ring)
 637 {
 638         int i, err = -ENOMEM;
 639         struct b43_dmadesc_generic *desc;
 640         struct b43_dmadesc_meta *meta;
 641
 642         for (i = 0; i < ring->nr_slots; i++) {
 643                 desc = ring->ops->idx2desc(ring, i, &meta);
 644
 645                 err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
 646                 if (err) {
 647                         b43err(ring->dev->wl,
 648                                "Failed to allocate initial descbuffers\n");
 649                         goto err_unwind;
 650                 }
 651         }
 652         mb();
 653         ring->used_slots = ring->nr_slots;
 654         err = 0;
 655       out:
 656         return err;
 657
 658       err_unwind:
 659         for (i--; i >= 0; i--) {
 660                 desc = ring->ops->idx2desc(ring, i, &meta);
 661
 662                 unmap_descbuffer(ring, meta->dmaaddr, ring->rx_buffersize, 0);
 663                 dev_kfree_skb(meta->skb);
 664         }
 665         goto out;
 666 }
 667
 668 /* Do initial setup of the DMA controller.
 669  * Reset the controller, write the ring busaddress
 670  * and switch the "enable" bit on.
 671  */
 672 static int dmacontroller_setup(struct b43_dmaring *ring)
 673 {
 674         int err = 0;
 675         u32 value;
 676         u32 addrext;
 677         u32 trans = ssb_dma_translation(ring->dev->dev);
 678
 679         if (ring->tx) {
 680                 if (ring->type == B43_DMA_64BIT) {
 681                         u64 ringbase = (u64) (ring->dmabase);
 682
 683                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 684                             >> SSB_DMA_TRANSLATION_SHIFT;
 685                         value = B43_DMA64_TXENABLE;
 686                         value |= (addrext << B43_DMA64_TXADDREXT_SHIFT)
 687                             & B43_DMA64_TXADDREXT_MASK;
 688                         b43_dma_write(ring, B43_DMA64_TXCTL, value);
 689                         b43_dma_write(ring, B43_DMA64_TXRINGLO,
 690                                       (ringbase & 0xFFFFFFFF));
 691                         b43_dma_write(ring, B43_DMA64_TXRINGHI,
 692                                       ((ringbase >> 32) &
 693                                        ~SSB_DMA_TRANSLATION_MASK)
 694                                       | (trans << 1));
 695                 } else {
 696                         u32 ringbase = (u32) (ring->dmabase);
 697
 698                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 699                             >> SSB_DMA_TRANSLATION_SHIFT;
 700                         value = B43_DMA32_TXENABLE;
 701                         value |= (addrext << B43_DMA32_TXADDREXT_SHIFT)
 702                             & B43_DMA32_TXADDREXT_MASK;
 703                         b43_dma_write(ring, B43_DMA32_TXCTL, value);
 704                         b43_dma_write(ring, B43_DMA32_TXRING,
 705                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 706                                       | trans);
 707                 }
 708         } else {
 709                 err = alloc_initial_descbuffers(ring);
 710                 if (err)
 711                         goto out;
 712                 if (ring->type == B43_DMA_64BIT) {
 713                         u64 ringbase = (u64) (ring->dmabase);
 714
 715                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 716                             >> SSB_DMA_TRANSLATION_SHIFT;
 717                         value = (ring->frameoffset << B43_DMA64_RXFROFF_SHIFT);
 718                         value |= B43_DMA64_RXENABLE;
 719                         value |= (addrext << B43_DMA64_RXADDREXT_SHIFT)
 720                             & B43_DMA64_RXADDREXT_MASK;
 721                         b43_dma_write(ring, B43_DMA64_RXCTL, value);
 722                         b43_dma_write(ring, B43_DMA64_RXRINGLO,
 723                                       (ringbase & 0xFFFFFFFF));
 724                         b43_dma_write(ring, B43_DMA64_RXRINGHI,
 725                                       ((ringbase >> 32) &
 726                                        ~SSB_DMA_TRANSLATION_MASK)
 727                                       | (trans << 1));
 728                         b43_dma_write(ring, B43_DMA64_RXINDEX, ring->nr_slots *
 729                                       sizeof(struct b43_dmadesc64));
 730                 } else {
 731                         u32 ringbase = (u32) (ring->dmabase);
 732
 733                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 734                             >> SSB_DMA_TRANSLATION_SHIFT;
 735                         value = (ring->frameoffset << B43_DMA32_RXFROFF_SHIFT);
 736                         value |= B43_DMA32_RXENABLE;
 737                         value |= (addrext << B43_DMA32_RXADDREXT_SHIFT)
 738                             & B43_DMA32_RXADDREXT_MASK;
 739                         b43_dma_write(ring, B43_DMA32_RXCTL, value);
 740                         b43_dma_write(ring, B43_DMA32_RXRING,
 741                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 742                                       | trans);
 743                         b43_dma_write(ring, B43_DMA32_RXINDEX, ring->nr_slots *
 744                                       sizeof(struct b43_dmadesc32));
 745                 }
 746         }
 747
 748 out:
 749         return err;
 750 }
 751
 752 /* Shutdown the DMA controller. */
 753 static void dmacontroller_cleanup(struct b43_dmaring *ring)
 754 {
 755         if (ring->tx) {
 756                 b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
 757                                            ring->type);
 758                 if (ring->type == B43_DMA_64BIT) {
 759                         b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
 760                         b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
 761                 } else
 762                         b43_dma_write(ring, B43_DMA32_TXRING, 0);
 763         } else {
 764                 b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
 765                                            ring->type);
 766                 if (ring->type == B43_DMA_64BIT) {
 767                         b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
 768                         b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
 769                 } else
 770                         b43_dma_write(ring, B43_DMA32_RXRING, 0);
 771         }
 772 }
 773
 774 static void free_all_descbuffers(struct b43_dmaring *ring)
 775 {
 776         struct b43_dmadesc_generic *desc;
 777         struct b43_dmadesc_meta *meta;
 778         int i;
 779
 780         if (!ring->used_slots)
 781                 return;
 782         for (i = 0; i < ring->nr_slots; i++) {
 783                 desc = ring->ops->idx2desc(ring, i, &meta);
 784
 785                 if (!meta->skb) {
 786                         B43_WARN_ON(!ring->tx);
 787                         continue;
 788                 }
 789                 if (ring->tx) {
 790                         unmap_descbuffer(ring, meta->dmaaddr,
 791                                          meta->skb->len, 1);
 792                 } else {
 793                         unmap_descbuffer(ring, meta->dmaaddr,
 794                                          ring->rx_buffersize, 0);
 795                 }
 796                 free_descriptor_buffer(ring, meta);
 797         }
 798 }
 799
 800 static u64 supported_dma_mask(struct b43_wldev *dev)
 801 {
 802         u32 tmp;
 803         u16 mmio_base;
 804
 805         tmp = b43_read32(dev, SSB_TMSHIGH);
 806         if (tmp & SSB_TMSHIGH_DMA64)
 807                 return DMA_64BIT_MASK;
 808         mmio_base = b43_dmacontroller_base(0, 0);
 809         b43_write32(dev, mmio_base + B43_DMA32_TXCTL, B43_DMA32_TXADDREXT_MASK);
 810         tmp = b43_read32(dev, mmio_base + B43_DMA32_TXCTL);
 811         if (tmp & B43_DMA32_TXADDREXT_MASK)
 812                 return DMA_32BIT_MASK;
 813
 814         return DMA_30BIT_MASK;
 815 }
 816
 817 /* Main initialization function. */
 818 static
 819 struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
 820                                       int controller_index,
 821                                       int for_tx,
 822                                       enum b43_dmatype type)
 823 {
 824         struct b43_dmaring *ring;
 825         int err;
 826         int nr_slots;
 827         dma_addr_t dma_test;
 828
 829         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 830         if (!ring)
 831                 goto out;
 832         ring->type = type;
 833
 834         nr_slots = B43_RXRING_SLOTS;
 835         if (for_tx)
 836                 nr_slots = B43_TXRING_SLOTS;
 837
 838         ring->meta = kcalloc(nr_slots, sizeof(struct b43_dmadesc_meta),
 839                              GFP_KERNEL);
 840         if (!ring->meta)
 841                 goto err_kfree_ring;
 842         if (for_tx) {
 843                 ring->txhdr_cache = kcalloc(nr_slots,
 844                                             b43_txhdr_size(dev),
 845                                             GFP_KERNEL);
 846                 if (!ring->txhdr_cache)
 847                         goto err_kfree_meta;
 848
 849                 /* test for ability to dma to txhdr_cache */
 850                 dma_test = dma_map_single(dev->dev->dev,
 851                                           ring->txhdr_cache,
 852                                           b43_txhdr_size(dev),
 853                                           DMA_TO_DEVICE);
 854
 855                 if (b43_dma_mapping_error(ring, dma_test, b43_txhdr_size(dev))) {
 856                         /* ugh realloc */
 857                         kfree(ring->txhdr_cache);
 858                         ring->txhdr_cache = kcalloc(nr_slots,
 859                                                     b43_txhdr_size(dev),
 860                                                     GFP_KERNEL | GFP_DMA);
 861                         if (!ring->txhdr_cache)
 862                                 goto err_kfree_meta;
 863
 864                         dma_test = dma_map_single(dev->dev->dev,
 865                                                   ring->txhdr_cache,
 866                                                   b43_txhdr_size(dev),
 867                                                   DMA_TO_DEVICE);
 868
 869                         if (b43_dma_mapping_error(ring, dma_test,
 870                                                   b43_txhdr_size(dev)))
 871                                 goto err_kfree_txhdr_cache;
 872                 }
 873
 874                 dma_unmap_single(dev->dev->dev,
 875                                  dma_test, b43_txhdr_size(dev),
 876                                  DMA_TO_DEVICE);
 877         }
 878
 879         ring->dev = dev;
 880         ring->nr_slots = nr_slots;
 881         ring->mmio_base = b43_dmacontroller_base(type, controller_index);
 882         ring->index = controller_index;
 883         if (type == B43_DMA_64BIT)
 884                 ring->ops = &dma64_ops;
 885         else
 886                 ring->ops = &dma32_ops;
 887         if (for_tx) {
 888                 ring->tx = 1;
 889                 ring->current_slot = -1;
 890         } else {
 891                 if (ring->index == 0) {
 892                         ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
 893                         ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
 894                 } else if (ring->index == 3) {
 895                         ring->rx_buffersize = B43_DMA3_RX_BUFFERSIZE;
 896                         ring->frameoffset = B43_DMA3_RX_FRAMEOFFSET;
 897                 } else
 898                         B43_WARN_ON(1);
 899         }
 900         spin_lock_init(&ring->lock);
 901 #ifdef CONFIG_B43_DEBUG
 902         ring->last_injected_overflow = jiffies;
 903 #endif
 904
 905         err = alloc_ringmemory(ring);
 906         if (err)
 907                 goto err_kfree_txhdr_cache;
 908         err = dmacontroller_setup(ring);
 909         if (err)
 910                 goto err_free_ringmemory;
 911
 912       out:
 913         return ring;
 914
 915       err_free_ringmemory:
 916         free_ringmemory(ring);
 917       err_kfree_txhdr_cache:
 918         kfree(ring->txhdr_cache);
 919       err_kfree_meta:
 920         kfree(ring->meta);
 921       err_kfree_ring:
 922         kfree(ring);
 923         ring = NULL;
 924         goto out;
 925 }
 926
 927 /* Main cleanup function. */
 928 static void b43_destroy_dmaring(struct b43_dmaring *ring)
 929 {
 930         if (!ring)
 931                 return;
 932
 933         b43dbg(ring->dev->wl, "DMA-%u 0x%04X (%s) max used slots: %d/%d\n",
 934                (unsigned int)(ring->type),
 935                ring->mmio_base,
 936                (ring->tx) ? "TX" : "RX", ring->max_used_slots, ring->nr_slots);
 937         /* Device IRQs are disabled prior entering this function,
 938          * so no need to take care of concurrency with rx handler stuff.
 939          */
 940         dmacontroller_cleanup(ring);
 941         free_all_descbuffers(ring);
 942         free_ringmemory(ring);
 943
 944         kfree(ring->txhdr_cache);
 945         kfree(ring->meta);
 946         kfree(ring);
 947 }
 948
 949 void b43_dma_free(struct b43_wldev *dev)
 950 {
 951         struct b43_dma *dma = &dev->dma;
 952
 953         b43_destroy_dmaring(dma->rx_ring3);
 954         dma->rx_ring3 = NULL;
 955         b43_destroy_dmaring(dma->rx_ring0);
 956         dma->rx_ring0 = NULL;
 957
 958         b43_destroy_dmaring(dma->tx_ring5);
 959         dma->tx_ring5 = NULL;
 960         b43_destroy_dmaring(dma->tx_ring4);
 961         dma->tx_ring4 = NULL;
 962         b43_destroy_dmaring(dma->tx_ring3);
 963         dma->tx_ring3 = NULL;
 964         b43_destroy_dmaring(dma->tx_ring2);
 965         dma->tx_ring2 = NULL;
 966         b43_destroy_dmaring(dma->tx_ring1);
 967         dma->tx_ring1 = NULL;
 968         b43_destroy_dmaring(dma->tx_ring0);
 969         dma->tx_ring0 = NULL;
 970 }
 971
 972 int b43_dma_init(struct b43_wldev *dev)
 973 {
 974         struct b43_dma *dma = &dev->dma;
 975         struct b43_dmaring *ring;
 976         int err;
 977         u64 dmamask;
 978         enum b43_dmatype type;
 979
 980         dmamask = supported_dma_mask(dev);
 981         switch (dmamask) {
 982         default:
 983                 B43_WARN_ON(1);
 984         case DMA_30BIT_MASK:
 985                 type = B43_DMA_30BIT;
 986                 break;
 987         case DMA_32BIT_MASK:
 988                 type = B43_DMA_32BIT;
 989                 break;
 990         case DMA_64BIT_MASK:
 991                 type = B43_DMA_64BIT;
 992                 break;
 993         }
 994         err = ssb_dma_set_mask(dev->dev, dmamask);
 995         if (err) {
 996                 b43err(dev->wl, "The machine/kernel does not support "
 997                        "the required DMA mask (0x%08X%08X)\n",
 998                        (unsigned int)((dmamask & 0xFFFFFFFF00000000ULL) >> 32),
 999                        (unsigned int)(dmamask & 0x00000000FFFFFFFFULL));
1000                 return -EOPNOTSUPP;
1001         }
1002
1003         err = -ENOMEM;
1004         /* setup TX DMA channels. */
1005         ring = b43_setup_dmaring(dev, 0, 1, type);
1006         if (!ring)
1007                 goto out;
1008         dma->tx_ring0 = ring;
1009
1010         ring = b43_setup_dmaring(dev, 1, 1, type);
1011         if (!ring)
1012                 goto err_destroy_tx0;
1013         dma->tx_ring1 = ring;
1014
1015         ring = b43_setup_dmaring(dev, 2, 1, type);
1016         if (!ring)
1017                 goto err_destroy_tx1;
1018         dma->tx_ring2 = ring;
1019
1020         ring = b43_setup_dmaring(dev, 3, 1, type);
1021         if (!ring)
1022                 goto err_destroy_tx2;
1023         dma->tx_ring3 = ring;
1024
1025         ring = b43_setup_dmaring(dev, 4, 1, type);
1026         if (!ring)
1027                 goto err_destroy_tx3;
1028         dma->tx_ring4 = ring;
1029
1030         ring = b43_setup_dmaring(dev, 5, 1, type);
1031         if (!ring)
1032                 goto err_destroy_tx4;
1033         dma->tx_ring5 = ring;
1034
1035         /* setup RX DMA channels. */
1036         ring = b43_setup_dmaring(dev, 0, 0, type);
1037         if (!ring)
1038                 goto err_destroy_tx5;
1039         dma->rx_ring0 = ring;
1040
1041         if (dev->dev->id.revision < 5) {
1042                 ring = b43_setup_dmaring(dev, 3, 0, type);
1043                 if (!ring)
1044                         goto err_destroy_rx0;
1045                 dma->rx_ring3 = ring;
1046         }
1047
1048         b43dbg(dev->wl, "%u-bit DMA initialized\n",
1049                (unsigned int)type);
1050         err = 0;
1051       out:
1052         return err;
1053
1054       err_destroy_rx0:
1055         b43_destroy_dmaring(dma->rx_ring0);
1056         dma->rx_ring0 = NULL;
1057       err_destroy_tx5:
1058         b43_destroy_dmaring(dma->tx_ring5);
1059         dma->tx_ring5 = NULL;
1060       err_destroy_tx4:
1061         b43_destroy_dmaring(dma->tx_ring4);
1062         dma->tx_ring4 = NULL;
1063       err_destroy_tx3:
1064         b43_destroy_dmaring(dma->tx_ring3);
1065         dma->tx_ring3 = NULL;
1066       err_destroy_tx2:
1067         b43_destroy_dmaring(dma->tx_ring2);
1068         dma->tx_ring2 = NULL;
1069       err_destroy_tx1:
1070         b43_destroy_dmaring(dma->tx_ring1);
1071         dma->tx_ring1 = NULL;
1072       err_destroy_tx0:
1073         b43_destroy_dmaring(dma->tx_ring0);
1074         dma->tx_ring0 = NULL;
1075         goto out;
1076 }
1077
1078 /* Generate a cookie for the TX header. */
1079 static u16 generate_cookie(struct b43_dmaring *ring, int slot)
1080 {
1081         u16 cookie = 0x1000;
1082
1083         /* Use the upper 4 bits of the cookie as
1084          * DMA controller ID and store the slot number
1085          * in the lower 12 bits.
1086          * Note that the cookie must never be 0, as this
1087          * is a special value used in RX path.
1088          * It can also not be 0xFFFF because that is special
1089          * for multicast frames.
1090          */
1091         switch (ring->index) {
1092         case 0:
1093                 cookie = 0x1000;
1094                 break;
1095         case 1:
1096                 cookie = 0x2000;
1097                 break;
1098         case 2:
1099                 cookie = 0x3000;
1100                 break;
1101         case 3:
1102                 cookie = 0x4000;
1103                 break;
1104         case 4:
1105                 cookie = 0x5000;
1106                 break;
1107         case 5:
1108                 cookie = 0x6000;
1109                 break;
1110         default:
1111                 B43_WARN_ON(1);
1112         }
1113         B43_WARN_ON(slot & ~0x0FFF);
1114         cookie |= (u16) slot;
1115
1116         return cookie;
1117 }
1118
1119 /* Inspect a cookie and find out to which controller/slot it belongs. */
1120 static
1121 struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
1122 {
1123         struct b43_dma *dma = &dev->dma;
1124         struct b43_dmaring *ring = NULL;
1125
1126         switch (cookie & 0xF000) {
1127         case 0x1000:
1128                 ring = dma->tx_ring0;
1129                 break;
1130         case 0x2000:
1131                 ring = dma->tx_ring1;
1132                 break;
1133         case 0x3000:
1134                 ring = dma->tx_ring2;
1135                 break;
1136         case 0x4000:
1137                 ring = dma->tx_ring3;
1138                 break;
1139         case 0x5000:
1140                 ring = dma->tx_ring4;
1141                 break;
1142         case 0x6000:
1143                 ring = dma->tx_ring5;
1144                 break;
1145         default:
1146                 B43_WARN_ON(1);
1147         }
1148         *slot = (cookie & 0x0FFF);
1149         B43_WARN_ON(!(ring && *slot >= 0 && *slot < ring->nr_slots));
1150
1151         return ring;
1152 }
1153
1154 static int dma_tx_fragment(struct b43_dmaring *ring,
1155                            struct sk_buff *skb,
1156                            struct ieee80211_tx_control *ctl)
1157 {
1158         const struct b43_dma_ops *ops = ring->ops;
1159         u8 *header;
1160         int slot, old_top_slot, old_used_slots;
1161         int err;
1162         struct b43_dmadesc_generic *desc;
1163         struct b43_dmadesc_meta *meta;
1164         struct b43_dmadesc_meta *meta_hdr;
1165         struct sk_buff *bounce_skb;
1166         u16 cookie;
1167         size_t hdrsize = b43_txhdr_size(ring->dev);
1168
1169 #define SLOTS_PER_PACKET  2
1170         B43_WARN_ON(skb_shinfo(skb)->nr_frags);
1171
1172         old_top_slot = ring->current_slot;
1173         old_used_slots = ring->used_slots;
1174
1175         /* Get a slot for the header. */
1176         slot = request_slot(ring);
1177         desc = ops->idx2desc(ring, slot, &meta_hdr);
1178         memset(meta_hdr, 0, sizeof(*meta_hdr));
1179
1180         header = &(ring->txhdr_cache[slot * hdrsize]);
1181         cookie = generate_cookie(ring, slot);
1182         err = b43_generate_txhdr(ring->dev, header,
1183                                  skb->data, skb->len, ctl, cookie);
1184         if (unlikely(err)) {
1185                 ring->current_slot = old_top_slot;
1186                 ring->used_slots = old_used_slots;
1187                 return err;
1188         }
1189
1190         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1191                                            hdrsize, 1);
1192         if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize)) {
1193                 ring->current_slot = old_top_slot;
1194                 ring->used_slots = old_used_slots;
1195                 return -EIO;
1196         }
1197         ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1198                              hdrsize, 1, 0, 0);
1199
1200         /* Get a slot for the payload. */
1201         slot = request_slot(ring);
1202         desc = ops->idx2desc(ring, slot, &meta);
1203         memset(meta, 0, sizeof(*meta));
1204
1205         memcpy(&meta->txstat.control, ctl, sizeof(*ctl));
1206         meta->skb = skb;
1207         meta->is_last_fragment = 1;
1208
1209         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1210         /* create a bounce buffer in zone_dma on mapping failure. */
1211         if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len)) {
1212                 bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
1213                 if (!bounce_skb) {
1214                         ring->current_slot = old_top_slot;
1215                         ring->used_slots = old_used_slots;
1216                         err = -ENOMEM;
1217                         goto out_unmap_hdr;
1218                 }
1219
1220                 memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
1221                 dev_kfree_skb_any(skb);
1222                 skb = bounce_skb;
1223                 meta->skb = skb;
1224                 meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1225                 if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len)) {
1226                         ring->current_slot = old_top_slot;
1227                         ring->used_slots = old_used_slots;
1228                         err = -EIO;
1229                         goto out_free_bounce;
1230                 }
1231         }
1232
1233         ops->fill_descriptor(ring, desc, meta->dmaaddr, skb->len, 0, 1, 1);
1234
1235         if (ctl->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM) {
1236                 /* Tell the firmware about the cookie of the last
1237                  * mcast frame, so it can clear the more-data bit in it. */
1238                 b43_shm_write16(ring->dev, B43_SHM_SHARED,
1239                                 B43_SHM_SH_MCASTCOOKIE, cookie);
1240         }
1241         /* Now transfer the whole frame. */
1242         wmb();
1243         ops->poke_tx(ring, next_slot(ring, slot));
1244         return 0;
1245
1246 out_free_bounce:
1247         dev_kfree_skb_any(skb);
1248 out_unmap_hdr:
1249         unmap_descbuffer(ring, meta_hdr->dmaaddr,
1250                          hdrsize, 1);
1251         return err;
1252 }
1253
1254 static inline int should_inject_overflow(struct b43_dmaring *ring)
1255 {
1256 #ifdef CONFIG_B43_DEBUG
1257         if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
1258                 /* Check if we should inject another ringbuffer overflow
1259                  * to test handling of this situation in the stack. */
1260                 unsigned long next_overflow;
1261
1262                 next_overflow = ring->last_injected_overflow + HZ;
1263                 if (time_after(jiffies, next_overflow)) {
1264                         ring->last_injected_overflow = jiffies;
1265                         b43dbg(ring->dev->wl,
1266                                "Injecting TX ring overflow on "
1267                                "DMA controller %d\n", ring->index);
1268                         return 1;
1269                 }
1270         }
1271 #endif /* CONFIG_B43_DEBUG */
1272         return 0;
1273 }
1274
1275 int b43_dma_tx(struct b43_wldev *dev,
1276                struct sk_buff *skb, struct ieee80211_tx_control *ctl)
1277 {
1278         struct b43_dmaring *ring;
1279         struct ieee80211_hdr *hdr;
1280         int err = 0;
1281         unsigned long flags;
1282
1283         if (unlikely(skb->len < 2 + 2 + 6)) {
1284                 /* Too short, this can't be a valid frame. */
1285                 return -EINVAL;
1286         }
1287
1288         hdr = (struct ieee80211_hdr *)skb->data;
1289         if (ctl->flags & IEEE80211_TXCTL_SEND_AFTER_DTIM) {
1290                 /* The multicast ring will be sent after the DTIM */
1291                 ring = dev->dma.tx_ring4;
1292                 /* Set the more-data bit. Ucode will clear it on
1293                  * the last frame for us. */
1294                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1295         } else {
1296                 /* Decide by priority where to put this frame. */
1297                 ring = priority_to_txring(dev, ctl->queue);
1298         }
1299
1300         spin_lock_irqsave(&ring->lock, flags);
1301         B43_WARN_ON(!ring->tx);
1302         if (unlikely(free_slots(ring) < SLOTS_PER_PACKET)) {
1303                 b43warn(dev->wl, "DMA queue overflow\n");
1304                 err = -ENOSPC;
1305                 goto out_unlock;
1306         }
1307         /* Check if the queue was stopped in mac80211,
1308          * but we got called nevertheless.
1309          * That would be a mac80211 bug. */
1310         B43_WARN_ON(ring->stopped);
1311
1312         err = dma_tx_fragment(ring, skb, ctl);
1313         if (unlikely(err == -ENOKEY)) {
1314                 /* Drop this packet, as we don't have the encryption key
1315                  * anymore and must not transmit it unencrypted. */
1316                 dev_kfree_skb_any(skb);
1317                 err = 0;
1318                 goto out_unlock;
1319         }
1320         if (unlikely(err)) {
1321                 b43err(dev->wl, "DMA tx mapping failure\n");
1322                 goto out_unlock;
1323         }
1324         ring->nr_tx_packets++;
1325         if ((free_slots(ring) < SLOTS_PER_PACKET) ||
1326             should_inject_overflow(ring)) {
1327                 /* This TX ring is full. */
1328                 ieee80211_stop_queue(dev->wl->hw, txring_to_priority(ring));
1329                 ring->stopped = 1;
1330                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1331                         b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
1332                 }
1333         }
1334 out_unlock:
1335         spin_unlock_irqrestore(&ring->lock, flags);
1336
1337         return err;
1338 }
1339
1340 void b43_dma_handle_txstatus(struct b43_wldev *dev,
1341                              const struct b43_txstatus *status)
1342 {
1343         const struct b43_dma_ops *ops;
1344         struct b43_dmaring *ring;
1345         struct b43_dmadesc_generic *desc;
1346         struct b43_dmadesc_meta *meta;
1347         int slot;
1348
1349         ring = parse_cookie(dev, status->cookie, &slot);
1350         if (unlikely(!ring))
1351                 return;
1352         B43_WARN_ON(!irqs_disabled());
1353         spin_lock(&ring->lock);
1354
1355         B43_WARN_ON(!ring->tx);
1356         ops = ring->ops;
1357         while (1) {
1358                 B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
1359                 desc = ops->idx2desc(ring, slot, &meta);
1360
1361                 if (meta->skb)
1362                         unmap_descbuffer(ring, meta->dmaaddr, meta->skb->len,
1363                                          1);
1364                 else
1365                         unmap_descbuffer(ring, meta->dmaaddr,
1366                                          b43_txhdr_size(dev), 1);
1367
1368                 if (meta->is_last_fragment) {
1369                         B43_WARN_ON(!meta->skb);
1370                         /* Call back to inform the ieee80211 subsystem about the
1371                          * status of the transmission.
1372                          * Some fields of txstat are already filled in dma_tx().
1373                          */
1374                         if (status->acked) {
1375                                 meta->txstat.flags |= IEEE80211_TX_STATUS_ACK;
1376                         } else {
1377                                 if (!(meta->txstat.control.flags
1378                                       & IEEE80211_TXCTL_NO_ACK))
1379                                         meta->txstat.excessive_retries = 1;
1380                         }
1381                         if (status->frame_count == 0) {
1382                                 /* The frame was not transmitted at all. */
1383                                 meta->txstat.retry_count = 0;
1384                         } else
1385                                 meta->txstat.retry_count = status->frame_count - 1;
1386                         ieee80211_tx_status_irqsafe(dev->wl->hw, meta->skb,
1387                                                     &(meta->txstat));
1388                         /* skb is freed by ieee80211_tx_status_irqsafe() */
1389                         meta->skb = NULL;
1390                 } else {
1391                         /* No need to call free_descriptor_buffer here, as
1392                          * this is only the txhdr, which is not allocated.
1393                          */
1394                         B43_WARN_ON(meta->skb);
1395                 }
1396
1397                 /* Everything unmapped and free'd. So it's not used anymore. */
1398                 ring->used_slots--;
1399
1400                 if (meta->is_last_fragment)
1401                         break;
1402                 slot = next_slot(ring, slot);
1403         }
1404         dev->stats.last_tx = jiffies;
1405         if (ring->stopped) {
1406                 B43_WARN_ON(free_slots(ring) < SLOTS_PER_PACKET);
1407                 ieee80211_wake_queue(dev->wl->hw, txring_to_priority(ring));
1408                 ring->stopped = 0;
1409                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1410                         b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
1411                 }
1412         }
1413
1414         spin_unlock(&ring->lock);
1415 }
1416
1417 void b43_dma_get_tx_stats(struct b43_wldev *dev,
1418                           struct ieee80211_tx_queue_stats *stats)
1419 {
1420         const int nr_queues = dev->wl->hw->queues;
1421         struct b43_dmaring *ring;
1422         struct ieee80211_tx_queue_stats_data *data;
1423         unsigned long flags;
1424         int i;
1425
1426         for (i = 0; i < nr_queues; i++) {
1427                 data = &(stats->data[i]);
1428                 ring = priority_to_txring(dev, i);
1429
1430                 spin_lock_irqsave(&ring->lock, flags);
1431                 data->len = ring->used_slots / SLOTS_PER_PACKET;
1432                 data->limit = ring->nr_slots / SLOTS_PER_PACKET;
1433                 data->count = ring->nr_tx_packets;
1434                 spin_unlock_irqrestore(&ring->lock, flags);
1435         }
1436 }
1437
1438 static void dma_rx(struct b43_dmaring *ring, int *slot)
1439 {
1440         const struct b43_dma_ops *ops = ring->ops;
1441         struct b43_dmadesc_generic *desc;
1442         struct b43_dmadesc_meta *meta;
1443         struct b43_rxhdr_fw4 *rxhdr;
1444         struct sk_buff *skb;
1445         u16 len;
1446         int err;
1447         dma_addr_t dmaaddr;
1448
1449         desc = ops->idx2desc(ring, *slot, &meta);
1450
1451         sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1452         skb = meta->skb;
1453
1454         if (ring->index == 3) {
1455                 /* We received an xmit status. */
1456                 struct b43_hwtxstatus *hw = (struct b43_hwtxstatus *)skb->data;
1457                 int i = 0;
1458
1459                 while (hw->cookie == 0) {
1460                         if (i > 100)
1461                                 break;
1462                         i++;
1463                         udelay(2);
1464                         barrier();
1465                 }
1466                 b43_handle_hwtxstatus(ring->dev, hw);
1467                 /* recycle the descriptor buffer. */
1468                 sync_descbuffer_for_device(ring, meta->dmaaddr,
1469                                            ring->rx_buffersize);
1470
1471                 return;
1472         }
1473         rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
1474         len = le16_to_cpu(rxhdr->frame_len);
1475         if (len == 0) {
1476                 int i = 0;
1477
1478                 do {
1479                         udelay(2);
1480                         barrier();
1481                         len = le16_to_cpu(rxhdr->frame_len);
1482                 } while (len == 0 && i++ < 5);
1483                 if (unlikely(len == 0)) {
1484                         /* recycle the descriptor buffer. */
1485                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1486                                                    ring->rx_buffersize);
1487                         goto drop;
1488                 }
1489         }
1490         if (unlikely(len > ring->rx_buffersize)) {
1491                 /* The data did not fit into one descriptor buffer
1492                  * and is split over multiple buffers.
1493                  * This should never happen, as we try to allocate buffers
1494                  * big enough. So simply ignore this packet.
1495                  */
1496                 int cnt = 0;
1497                 s32 tmp = len;
1498
1499                 while (1) {
1500                         desc = ops->idx2desc(ring, *slot, &meta);
1501                         /* recycle the descriptor buffer. */
1502                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1503                                                    ring->rx_buffersize);
1504                         *slot = next_slot(ring, *slot);
1505                         cnt++;
1506                         tmp -= ring->rx_buffersize;
1507                         if (tmp <= 0)
1508                                 break;
1509                 }
1510                 b43err(ring->dev->wl, "DMA RX buffer too small "
1511                        "(len: %u, buffer: %u, nr-dropped: %d)\n",
1512                        len, ring->rx_buffersize, cnt);
1513                 goto drop;
1514         }
1515
1516         dmaaddr = meta->dmaaddr;
1517         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1518         if (unlikely(err)) {
1519                 b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
1520                 sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
1521                 goto drop;
1522         }
1523
1524         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1525         skb_put(skb, len + ring->frameoffset);
1526         skb_pull(skb, ring->frameoffset);
1527
1528         b43_rx(ring->dev, skb, rxhdr);
1529       drop:
1530         return;
1531 }
1532
1533 void b43_dma_rx(struct b43_dmaring *ring)
1534 {
1535         const struct b43_dma_ops *ops = ring->ops;
1536         int slot, current_slot;
1537         int used_slots = 0;
1538
1539         B43_WARN_ON(ring->tx);
1540         current_slot = ops->get_current_rxslot(ring);
1541         B43_WARN_ON(!(current_slot >= 0 && current_slot < ring->nr_slots));
1542
1543         slot = ring->current_slot;
1544         for (; slot != current_slot; slot = next_slot(ring, slot)) {
1545                 dma_rx(ring, &slot);
1546                 update_max_used_slots(ring, ++used_slots);
1547         }
1548         ops->set_current_rxslot(ring, slot);
1549         ring->current_slot = slot;
1550 }
1551
1552 static void b43_dma_tx_suspend_ring(struct b43_dmaring *ring)
1553 {
1554         unsigned long flags;
1555
1556         spin_lock_irqsave(&ring->lock, flags);
1557         B43_WARN_ON(!ring->tx);
1558         ring->ops->tx_suspend(ring);
1559         spin_unlock_irqrestore(&ring->lock, flags);
1560 }
1561
1562 static void b43_dma_tx_resume_ring(struct b43_dmaring *ring)
1563 {
1564         unsigned long flags;
1565
1566         spin_lock_irqsave(&ring->lock, flags);
1567         B43_WARN_ON(!ring->tx);
1568         ring->ops->tx_resume(ring);
1569         spin_unlock_irqrestore(&ring->lock, flags);
1570 }
1571
1572 void b43_dma_tx_suspend(struct b43_wldev *dev)
1573 {
1574         b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
1575         b43_dma_tx_suspend_ring(dev->dma.tx_ring0);
1576         b43_dma_tx_suspend_ring(dev->dma.tx_ring1);
1577         b43_dma_tx_suspend_ring(dev->dma.tx_ring2);
1578         b43_dma_tx_suspend_ring(dev->dma.tx_ring3);
1579         b43_dma_tx_suspend_ring(dev->dma.tx_ring4);
1580         b43_dma_tx_suspend_ring(dev->dma.tx_ring5);
1581 }
1582
1583 void b43_dma_tx_resume(struct b43_wldev *dev)
1584 {
1585         b43_dma_tx_resume_ring(dev->dma.tx_ring5);
1586         b43_dma_tx_resume_ring(dev->dma.tx_ring4);
1587         b43_dma_tx_resume_ring(dev->dma.tx_ring3);
1588         b43_dma_tx_resume_ring(dev->dma.tx_ring2);
1589         b43_dma_tx_resume_ring(dev->dma.tx_ring1);
1590         b43_dma_tx_resume_ring(dev->dma.tx_ring0);
1591         b43_power_saving_ctl_bits(dev, 0);
1592 }