SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 <net/dst.h>
  41
  42 /* 32bit DMA ops. */
  43 static
  44 struct b43legacy_dmadesc_generic *op32_idx2desc(
  45                                         struct b43legacy_dmaring *ring,
  46                                         int slot,
  47                                         struct b43legacy_dmadesc_meta **meta)
  48 {
  49         struct b43legacy_dmadesc32 *desc;
  50
  51         *meta = &(ring->meta[slot]);
  52         desc = ring->descbase;
  53         desc = &(desc[slot]);
  54
  55         return (struct b43legacy_dmadesc_generic *)desc;
  56 }
  57
  58 static void op32_fill_descriptor(struct b43legacy_dmaring *ring,
  59                                  struct b43legacy_dmadesc_generic *desc,
  60                                  dma_addr_t dmaaddr, u16 bufsize,
  61                                  int start, int end, int irq)
  62 {
  63         struct b43legacy_dmadesc32 *descbase = ring->descbase;
  64         int slot;
  65         u32 ctl;
  66         u32 addr;
  67         u32 addrext;
  68
  69         slot = (int)(&(desc->dma32) - descbase);
  70         B43legacy_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               & B43legacy_DMA32_DCTL_BYTECNT;
  78         if (slot == ring->nr_slots - 1)
  79                 ctl |= B43legacy_DMA32_DCTL_DTABLEEND;
  80         if (start)
  81                 ctl |= B43legacy_DMA32_DCTL_FRAMESTART;
  82         if (end)
  83                 ctl |= B43legacy_DMA32_DCTL_FRAMEEND;
  84         if (irq)
  85                 ctl |= B43legacy_DMA32_DCTL_IRQ;
  86         ctl |= (addrext << B43legacy_DMA32_DCTL_ADDREXT_SHIFT)
  87                & B43legacy_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 b43legacy_dmaring *ring, int slot)
  94 {
  95         b43legacy_dma_write(ring, B43legacy_DMA32_TXINDEX,
  96                             (u32)(slot * sizeof(struct b43legacy_dmadesc32)));
  97 }
  98
  99 static void op32_tx_suspend(struct b43legacy_dmaring *ring)
 100 {
 101         b43legacy_dma_write(ring, B43legacy_DMA32_TXCTL,
 102                             b43legacy_dma_read(ring, B43legacy_DMA32_TXCTL)
 103                             | B43legacy_DMA32_TXSUSPEND);
 104 }
 105
 106 static void op32_tx_resume(struct b43legacy_dmaring *ring)
 107 {
 108         b43legacy_dma_write(ring, B43legacy_DMA32_TXCTL,
 109                             b43legacy_dma_read(ring, B43legacy_DMA32_TXCTL)
 110                             & ~B43legacy_DMA32_TXSUSPEND);
 111 }
 112
 113 static int op32_get_current_rxslot(struct b43legacy_dmaring *ring)
 114 {
 115         u32 val;
 116
 117         val = b43legacy_dma_read(ring, B43legacy_DMA32_RXSTATUS);
 118         val &= B43legacy_DMA32_RXDPTR;
 119
 120         return (val / sizeof(struct b43legacy_dmadesc32));
 121 }
 122
 123 static void op32_set_current_rxslot(struct b43legacy_dmaring *ring,
 124                                     int slot)
 125 {
 126         b43legacy_dma_write(ring, B43legacy_DMA32_RXINDEX,
 127                             (u32)(slot * sizeof(struct b43legacy_dmadesc32)));
 128 }
 129
 130 static const struct b43legacy_dma_ops dma32_ops = {
 131         .idx2desc               = op32_idx2desc,
 132         .fill_descriptor        = op32_fill_descriptor,
 133         .poke_tx                = op32_poke_tx,
 134         .tx_suspend             = op32_tx_suspend,
 135         .tx_resume              = op32_tx_resume,
 136         .get_current_rxslot     = op32_get_current_rxslot,
 137         .set_current_rxslot     = op32_set_current_rxslot,
 138 };
 139
 140 /* 64bit DMA ops. */
 141 static
 142 struct b43legacy_dmadesc_generic *op64_idx2desc(
 143                                         struct b43legacy_dmaring *ring,
 144                                         int slot,
 145                                         struct b43legacy_dmadesc_meta
 146                                         **meta)
 147 {
 148         struct b43legacy_dmadesc64 *desc;
 149
 150         *meta = &(ring->meta[slot]);
 151         desc = ring->descbase;
 152         desc = &(desc[slot]);
 153
 154         return (struct b43legacy_dmadesc_generic *)desc;
 155 }
 156
 157 static void op64_fill_descriptor(struct b43legacy_dmaring *ring,
 158                                  struct b43legacy_dmadesc_generic *desc,
 159                                  dma_addr_t dmaaddr, u16 bufsize,
 160                                  int start, int end, int irq)
 161 {
 162         struct b43legacy_dmadesc64 *descbase = ring->descbase;
 163         int slot;
 164         u32 ctl0 = 0;
 165         u32 ctl1 = 0;
 166         u32 addrlo;
 167         u32 addrhi;
 168         u32 addrext;
 169
 170         slot = (int)(&(desc->dma64) - descbase);
 171         B43legacy_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
 172
 173         addrlo = (u32)(dmaaddr & 0xFFFFFFFF);
 174         addrhi = (((u64)dmaaddr >> 32) & ~SSB_DMA_TRANSLATION_MASK);
 175         addrext = (((u64)dmaaddr >> 32) & SSB_DMA_TRANSLATION_MASK)
 176                   >> SSB_DMA_TRANSLATION_SHIFT;
 177         addrhi |= ssb_dma_translation(ring->dev->dev);
 178         if (slot == ring->nr_slots - 1)
 179                 ctl0 |= B43legacy_DMA64_DCTL0_DTABLEEND;
 180         if (start)
 181                 ctl0 |= B43legacy_DMA64_DCTL0_FRAMESTART;
 182         if (end)
 183                 ctl0 |= B43legacy_DMA64_DCTL0_FRAMEEND;
 184         if (irq)
 185                 ctl0 |= B43legacy_DMA64_DCTL0_IRQ;
 186         ctl1 |= (bufsize - ring->frameoffset)
 187                 & B43legacy_DMA64_DCTL1_BYTECNT;
 188         ctl1 |= (addrext << B43legacy_DMA64_DCTL1_ADDREXT_SHIFT)
 189                 & B43legacy_DMA64_DCTL1_ADDREXT_MASK;
 190
 191         desc->dma64.control0 = cpu_to_le32(ctl0);
 192         desc->dma64.control1 = cpu_to_le32(ctl1);
 193         desc->dma64.address_low = cpu_to_le32(addrlo);
 194         desc->dma64.address_high = cpu_to_le32(addrhi);
 195 }
 196
 197 static void op64_poke_tx(struct b43legacy_dmaring *ring, int slot)
 198 {
 199         b43legacy_dma_write(ring, B43legacy_DMA64_TXINDEX,
 200                             (u32)(slot * sizeof(struct b43legacy_dmadesc64)));
 201 }
 202
 203 static void op64_tx_suspend(struct b43legacy_dmaring *ring)
 204 {
 205         b43legacy_dma_write(ring, B43legacy_DMA64_TXCTL,
 206                             b43legacy_dma_read(ring, B43legacy_DMA64_TXCTL)
 207                             | B43legacy_DMA64_TXSUSPEND);
 208 }
 209
 210 static void op64_tx_resume(struct b43legacy_dmaring *ring)
 211 {
 212         b43legacy_dma_write(ring, B43legacy_DMA64_TXCTL,
 213                             b43legacy_dma_read(ring, B43legacy_DMA64_TXCTL)
 214                             & ~B43legacy_DMA64_TXSUSPEND);
 215 }
 216
 217 static int op64_get_current_rxslot(struct b43legacy_dmaring *ring)
 218 {
 219         u32 val;
 220
 221         val = b43legacy_dma_read(ring, B43legacy_DMA64_RXSTATUS);
 222         val &= B43legacy_DMA64_RXSTATDPTR;
 223
 224         return (val / sizeof(struct b43legacy_dmadesc64));
 225 }
 226
 227 static void op64_set_current_rxslot(struct b43legacy_dmaring *ring,
 228                                     int slot)
 229 {
 230         b43legacy_dma_write(ring, B43legacy_DMA64_RXINDEX,
 231                             (u32)(slot * sizeof(struct b43legacy_dmadesc64)));
 232 }
 233
 234 static const struct b43legacy_dma_ops dma64_ops = {
 235         .idx2desc               = op64_idx2desc,
 236         .fill_descriptor        = op64_fill_descriptor,
 237         .poke_tx                = op64_poke_tx,
 238         .tx_suspend             = op64_tx_suspend,
 239         .tx_resume              = op64_tx_resume,
 240         .get_current_rxslot     = op64_get_current_rxslot,
 241         .set_current_rxslot     = op64_set_current_rxslot,
 242 };
 243
 244
 245 static inline int free_slots(struct b43legacy_dmaring *ring)
 246 {
 247         return (ring->nr_slots - ring->used_slots);
 248 }
 249
 250 static inline int next_slot(struct b43legacy_dmaring *ring, int slot)
 251 {
 252         B43legacy_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
 253         if (slot == ring->nr_slots - 1)
 254                 return 0;
 255         return slot + 1;
 256 }
 257
 258 static inline int prev_slot(struct b43legacy_dmaring *ring, int slot)
 259 {
 260         B43legacy_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
 261         if (slot == 0)
 262                 return ring->nr_slots - 1;
 263         return slot - 1;
 264 }
 265
 266 #ifdef CONFIG_B43LEGACY_DEBUG
 267 static void update_max_used_slots(struct b43legacy_dmaring *ring,
 268                                   int current_used_slots)
 269 {
 270         if (current_used_slots <= ring->max_used_slots)
 271                 return;
 272         ring->max_used_slots = current_used_slots;
 273         if (b43legacy_debug(ring->dev, B43legacy_DBG_DMAVERBOSE))
 274                 b43legacydbg(ring->dev->wl,
 275                        "max_used_slots increased to %d on %s ring %d\n",
 276                        ring->max_used_slots,
 277                        ring->tx ? "TX" : "RX",
 278                        ring->index);
 279 }
 280 #else
 281 static inline
 282 void update_max_used_slots(struct b43legacy_dmaring *ring,
 283                            int current_used_slots)
 284 { }
 285 #endif /* DEBUG */
 286
 287 /* Request a slot for usage. */
 288 static inline
 289 int request_slot(struct b43legacy_dmaring *ring)
 290 {
 291         int slot;
 292
 293         B43legacy_WARN_ON(!ring->tx);
 294         B43legacy_WARN_ON(ring->stopped);
 295         B43legacy_WARN_ON(free_slots(ring) == 0);
 296
 297         slot = next_slot(ring, ring->current_slot);
 298         ring->current_slot = slot;
 299         ring->used_slots++;
 300
 301         update_max_used_slots(ring, ring->used_slots);
 302
 303         return slot;
 304 }
 305
 306 /* Mac80211-queue to b43legacy-ring mapping */
 307 static struct b43legacy_dmaring *priority_to_txring(
 308                                                 struct b43legacy_wldev *dev,
 309                                                 int queue_priority)
 310 {
 311         struct b43legacy_dmaring *ring;
 312
 313 /*FIXME: For now we always run on TX-ring-1 */
 314 return dev->dma.tx_ring1;
 315
 316         /* 0 = highest priority */
 317         switch (queue_priority) {
 318         default:
 319                 B43legacy_WARN_ON(1);
 320                 /* fallthrough */
 321         case 0:
 322                 ring = dev->dma.tx_ring3;
 323                 break;
 324         case 1:
 325                 ring = dev->dma.tx_ring2;
 326                 break;
 327         case 2:
 328                 ring = dev->dma.tx_ring1;
 329                 break;
 330         case 3:
 331                 ring = dev->dma.tx_ring0;
 332                 break;
 333         case 4:
 334                 ring = dev->dma.tx_ring4;
 335                 break;
 336         case 5:
 337                 ring = dev->dma.tx_ring5;
 338                 break;
 339         }
 340
 341         return ring;
 342 }
 343
 344 /* Bcm4301-ring to mac80211-queue mapping */
 345 static inline int txring_to_priority(struct b43legacy_dmaring *ring)
 346 {
 347         static const u8 idx_to_prio[] =
 348                 { 3, 2, 1, 0, 4, 5, };
 349
 350 /*FIXME: have only one queue, for now */
 351 return 0;
 352
 353         return idx_to_prio[ring->index];
 354 }
 355
 356
 357 static u16 b43legacy_dmacontroller_base(enum b43legacy_dmatype type,
 358                                         int controller_idx)
 359 {
 360         static const u16 map64[] = {
 361                 B43legacy_MMIO_DMA64_BASE0,
 362                 B43legacy_MMIO_DMA64_BASE1,
 363                 B43legacy_MMIO_DMA64_BASE2,
 364                 B43legacy_MMIO_DMA64_BASE3,
 365                 B43legacy_MMIO_DMA64_BASE4,
 366                 B43legacy_MMIO_DMA64_BASE5,
 367         };
 368         static const u16 map32[] = {
 369                 B43legacy_MMIO_DMA32_BASE0,
 370                 B43legacy_MMIO_DMA32_BASE1,
 371                 B43legacy_MMIO_DMA32_BASE2,
 372                 B43legacy_MMIO_DMA32_BASE3,
 373                 B43legacy_MMIO_DMA32_BASE4,
 374                 B43legacy_MMIO_DMA32_BASE5,
 375         };
 376
 377         if (type == B43legacy_DMA_64BIT) {
 378                 B43legacy_WARN_ON(!(controller_idx >= 0 &&
 379                                   controller_idx < ARRAY_SIZE(map64)));
 380                 return map64[controller_idx];
 381         }
 382         B43legacy_WARN_ON(!(controller_idx >= 0 &&
 383                           controller_idx < ARRAY_SIZE(map32)));
 384         return map32[controller_idx];
 385 }
 386
 387 static inline
 388 dma_addr_t map_descbuffer(struct b43legacy_dmaring *ring,
 389                           unsigned char *buf,
 390                           size_t len,
 391                           int tx)
 392 {
 393         dma_addr_t dmaaddr;
 394
 395         if (tx)
 396                 dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 397                                          buf, len,
 398                                          DMA_TO_DEVICE);
 399         else
 400                 dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 401                                          buf, len,
 402                                          DMA_FROM_DEVICE);
 403
 404         return dmaaddr;
 405 }
 406
 407 static inline
 408 void unmap_descbuffer(struct b43legacy_dmaring *ring,
 409                       dma_addr_t addr,
 410                       size_t len,
 411                       int tx)
 412 {
 413         if (tx)
 414                 dma_unmap_single(ring->dev->dev->dma_dev,
 415                                  addr, len,
 416                                  DMA_TO_DEVICE);
 417         else
 418                 dma_unmap_single(ring->dev->dev->dma_dev,
 419                                  addr, len,
 420                                  DMA_FROM_DEVICE);
 421 }
 422
 423 static inline
 424 void sync_descbuffer_for_cpu(struct b43legacy_dmaring *ring,
 425                              dma_addr_t addr,
 426                              size_t len)
 427 {
 428         B43legacy_WARN_ON(ring->tx);
 429
 430         dma_sync_single_for_cpu(ring->dev->dev->dma_dev,
 431                                 addr, len, DMA_FROM_DEVICE);
 432 }
 433
 434 static inline
 435 void sync_descbuffer_for_device(struct b43legacy_dmaring *ring,
 436                                 dma_addr_t addr,
 437                                 size_t len)
 438 {
 439         B43legacy_WARN_ON(ring->tx);
 440
 441         dma_sync_single_for_device(ring->dev->dev->dma_dev,
 442                                    addr, len, DMA_FROM_DEVICE);
 443 }
 444
 445 static inline
 446 void free_descriptor_buffer(struct b43legacy_dmaring *ring,
 447                             struct b43legacy_dmadesc_meta *meta,
 448                             int irq_context)
 449 {
 450         if (meta->skb) {
 451                 if (irq_context)
 452                         dev_kfree_skb_irq(meta->skb);
 453                 else
 454                         dev_kfree_skb(meta->skb);
 455                 meta->skb = NULL;
 456         }
 457 }
 458
 459 static int alloc_ringmemory(struct b43legacy_dmaring *ring)
 460 {
 461         struct device *dma_dev = ring->dev->dev->dma_dev;
 462
 463         ring->descbase = dma_alloc_coherent(dma_dev, B43legacy_DMA_RINGMEMSIZE,
 464                                             &(ring->dmabase), GFP_KERNEL);
 465         if (!ring->descbase) {
 466                 b43legacyerr(ring->dev->wl, "DMA ringmemory allocation"
 467                              " failed\n");
 468                 return -ENOMEM;
 469         }
 470         memset(ring->descbase, 0, B43legacy_DMA_RINGMEMSIZE);
 471
 472         return 0;
 473 }
 474
 475 static void free_ringmemory(struct b43legacy_dmaring *ring)
 476 {
 477         struct device *dma_dev = ring->dev->dev->dma_dev;
 478
 479         dma_free_coherent(dma_dev, B43legacy_DMA_RINGMEMSIZE,
 480                           ring->descbase, ring->dmabase);
 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(dma_mapping_error(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_64BIT_MASK;
 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_32BIT_MASK;
 859
 860         return DMA_30BIT_MASK;
 861 }
 862
 863 /* Main initialization function. */
 864 static
 865 struct b43legacy_dmaring *b43legacy_setup_dmaring(struct b43legacy_wldev *dev,
 866                                                   int controller_index,
 867                                                   int for_tx,
 868                                                   enum b43legacy_dmatype type)
 869 {
 870         struct b43legacy_dmaring *ring;
 871         int err;
 872         int nr_slots;
 873         dma_addr_t dma_test;
 874
 875         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 876         if (!ring)
 877                 goto out;
 878         ring->type = type;
 879
 880         nr_slots = B43legacy_RXRING_SLOTS;
 881         if (for_tx)
 882                 nr_slots = B43legacy_TXRING_SLOTS;
 883
 884         ring->meta = kcalloc(nr_slots, sizeof(struct b43legacy_dmadesc_meta),
 885                              GFP_KERNEL);
 886         if (!ring->meta)
 887                 goto err_kfree_ring;
 888         if (for_tx) {
 889                 ring->txhdr_cache = kcalloc(nr_slots,
 890                                         sizeof(struct b43legacy_txhdr_fw3),
 891                                         GFP_KERNEL);
 892                 if (!ring->txhdr_cache)
 893                         goto err_kfree_meta;
 894
 895                 /* test for ability to dma to txhdr_cache */
 896                 dma_test = dma_map_single(dev->dev->dma_dev, ring->txhdr_cache,
 897                                           sizeof(struct b43legacy_txhdr_fw3),
 898                                           DMA_TO_DEVICE);
 899
 900                 if (b43legacy_dma_mapping_error(ring, dma_test,
 901                                         sizeof(struct b43legacy_txhdr_fw3), 1)) {
 902                         /* ugh realloc */
 903                         kfree(ring->txhdr_cache);
 904                         ring->txhdr_cache = kcalloc(nr_slots,
 905                                         sizeof(struct b43legacy_txhdr_fw3),
 906                                         GFP_KERNEL | GFP_DMA);
 907                         if (!ring->txhdr_cache)
 908                                 goto err_kfree_meta;
 909
 910                         dma_test = dma_map_single(dev->dev->dma_dev,
 911                                         ring->txhdr_cache,
 912                                         sizeof(struct b43legacy_txhdr_fw3),
 913                                         DMA_TO_DEVICE);
 914
 915                         if (b43legacy_dma_mapping_error(ring, dma_test,
 916                                         sizeof(struct b43legacy_txhdr_fw3), 1))
 917                                 goto err_kfree_txhdr_cache;
 918                 }
 919
 920                 dma_unmap_single(dev->dev->dma_dev,
 921                                  dma_test, sizeof(struct b43legacy_txhdr_fw3),
 922                                  DMA_TO_DEVICE);
 923         }
 924
 925         ring->dev = dev;
 926         ring->nr_slots = nr_slots;
 927         ring->mmio_base = b43legacy_dmacontroller_base(type, controller_index);
 928         ring->index = controller_index;
 929         if (type == B43legacy_DMA_64BIT)
 930                 ring->ops = &dma64_ops;
 931         else
 932                 ring->ops = &dma32_ops;
 933         if (for_tx) {
 934                 ring->tx = 1;
 935                 ring->current_slot = -1;
 936         } else {
 937                 if (ring->index == 0) {
 938                         ring->rx_buffersize = B43legacy_DMA0_RX_BUFFERSIZE;
 939                         ring->frameoffset = B43legacy_DMA0_RX_FRAMEOFFSET;
 940                 } else if (ring->index == 3) {
 941                         ring->rx_buffersize = B43legacy_DMA3_RX_BUFFERSIZE;
 942                         ring->frameoffset = B43legacy_DMA3_RX_FRAMEOFFSET;
 943                 } else
 944                         B43legacy_WARN_ON(1);
 945         }
 946         spin_lock_init(&ring->lock);
 947 #ifdef CONFIG_B43LEGACY_DEBUG
 948         ring->last_injected_overflow = jiffies;
 949 #endif
 950
 951         err = alloc_ringmemory(ring);
 952         if (err)
 953                 goto err_kfree_txhdr_cache;
 954         err = dmacontroller_setup(ring);
 955         if (err)
 956                 goto err_free_ringmemory;
 957
 958 out:
 959         return ring;
 960
 961 err_free_ringmemory:
 962         free_ringmemory(ring);
 963 err_kfree_txhdr_cache:
 964         kfree(ring->txhdr_cache);
 965 err_kfree_meta:
 966         kfree(ring->meta);
 967 err_kfree_ring:
 968         kfree(ring);
 969         ring = NULL;
 970         goto out;
 971 }
 972
 973 /* Main cleanup function. */
 974 static void b43legacy_destroy_dmaring(struct b43legacy_dmaring *ring)
 975 {
 976         if (!ring)
 977                 return;
 978
 979         b43legacydbg(ring->dev->wl, "DMA-%u 0x%04X (%s) max used slots:"
 980                      " %d/%d\n", (unsigned int)(ring->type), ring->mmio_base,
 981                      (ring->tx) ? "TX" : "RX", ring->max_used_slots,
 982                      ring->nr_slots);
 983         /* Device IRQs are disabled prior entering this function,
 984          * so no need to take care of concurrency with rx handler stuff.
 985          */
 986         dmacontroller_cleanup(ring);
 987         free_all_descbuffers(ring);
 988         free_ringmemory(ring);
 989
 990         kfree(ring->txhdr_cache);
 991         kfree(ring->meta);
 992         kfree(ring);
 993 }
 994
 995 void b43legacy_dma_free(struct b43legacy_wldev *dev)
 996 {
 997         struct b43legacy_dma *dma;
 998
 999         if (b43legacy_using_pio(dev))
1000                 return;
1001         dma = &dev->dma;
1002
1003         b43legacy_destroy_dmaring(dma->rx_ring3);
1004         dma->rx_ring3 = NULL;
1005         b43legacy_destroy_dmaring(dma->rx_ring0);
1006         dma->rx_ring0 = NULL;
1007
1008         b43legacy_destroy_dmaring(dma->tx_ring5);
1009         dma->tx_ring5 = NULL;
1010         b43legacy_destroy_dmaring(dma->tx_ring4);
1011         dma->tx_ring4 = NULL;
1012         b43legacy_destroy_dmaring(dma->tx_ring3);
1013         dma->tx_ring3 = NULL;
1014         b43legacy_destroy_dmaring(dma->tx_ring2);
1015         dma->tx_ring2 = NULL;
1016         b43legacy_destroy_dmaring(dma->tx_ring1);
1017         dma->tx_ring1 = NULL;
1018         b43legacy_destroy_dmaring(dma->tx_ring0);
1019         dma->tx_ring0 = NULL;
1020 }
1021
1022 int b43legacy_dma_init(struct b43legacy_wldev *dev)
1023 {
1024         struct b43legacy_dma *dma = &dev->dma;
1025         struct b43legacy_dmaring *ring;
1026         int err;
1027         u64 dmamask;
1028         enum b43legacy_dmatype type;
1029
1030         dmamask = supported_dma_mask(dev);
1031         switch (dmamask) {
1032         default:
1033                 B43legacy_WARN_ON(1);
1034         case DMA_30BIT_MASK:
1035                 type = B43legacy_DMA_30BIT;
1036                 break;
1037         case DMA_32BIT_MASK:
1038                 type = B43legacy_DMA_32BIT;
1039                 break;
1040         case DMA_64BIT_MASK:
1041                 type = B43legacy_DMA_64BIT;
1042                 break;
1043         }
1044
1045         err = ssb_dma_set_mask(dev->dev, dmamask);
1046         if (err) {
1047 #ifdef CONFIG_B43LEGACY_PIO
1048                 b43legacywarn(dev->wl, "DMA for this device not supported. "
1049                         "Falling back to PIO\n");
1050                 dev->__using_pio = 1;
1051                 return -EAGAIN;
1052 #else
1053                 b43legacyerr(dev->wl, "DMA for this device not supported and "
1054                        "no PIO support compiled in\n");
1055                 return -EOPNOTSUPP;
1056 #endif
1057         }
1058
1059         err = -ENOMEM;
1060         /* setup TX DMA channels. */
1061         ring = b43legacy_setup_dmaring(dev, 0, 1, type);
1062         if (!ring)
1063                 goto out;
1064         dma->tx_ring0 = ring;
1065
1066         ring = b43legacy_setup_dmaring(dev, 1, 1, type);
1067         if (!ring)
1068                 goto err_destroy_tx0;
1069         dma->tx_ring1 = ring;
1070
1071         ring = b43legacy_setup_dmaring(dev, 2, 1, type);
1072         if (!ring)
1073                 goto err_destroy_tx1;
1074         dma->tx_ring2 = ring;
1075
1076         ring = b43legacy_setup_dmaring(dev, 3, 1, type);
1077         if (!ring)
1078                 goto err_destroy_tx2;
1079         dma->tx_ring3 = ring;
1080
1081         ring = b43legacy_setup_dmaring(dev, 4, 1, type);
1082         if (!ring)
1083                 goto err_destroy_tx3;
1084         dma->tx_ring4 = ring;
1085
1086         ring = b43legacy_setup_dmaring(dev, 5, 1, type);
1087         if (!ring)
1088                 goto err_destroy_tx4;
1089         dma->tx_ring5 = ring;
1090
1091         /* setup RX DMA channels. */
1092         ring = b43legacy_setup_dmaring(dev, 0, 0, type);
1093         if (!ring)
1094                 goto err_destroy_tx5;
1095         dma->rx_ring0 = ring;
1096
1097         if (dev->dev->id.revision < 5) {
1098                 ring = b43legacy_setup_dmaring(dev, 3, 0, type);
1099                 if (!ring)
1100                         goto err_destroy_rx0;
1101                 dma->rx_ring3 = ring;
1102         }
1103
1104         b43legacydbg(dev->wl, "%u-bit DMA initialized\n", (unsigned int)type);
1105         err = 0;
1106 out:
1107         return err;
1108
1109 err_destroy_rx0:
1110         b43legacy_destroy_dmaring(dma->rx_ring0);
1111         dma->rx_ring0 = NULL;
1112 err_destroy_tx5:
1113         b43legacy_destroy_dmaring(dma->tx_ring5);
1114         dma->tx_ring5 = NULL;
1115 err_destroy_tx4:
1116         b43legacy_destroy_dmaring(dma->tx_ring4);
1117         dma->tx_ring4 = NULL;
1118 err_destroy_tx3:
1119         b43legacy_destroy_dmaring(dma->tx_ring3);
1120         dma->tx_ring3 = NULL;
1121 err_destroy_tx2:
1122         b43legacy_destroy_dmaring(dma->tx_ring2);
1123         dma->tx_ring2 = NULL;
1124 err_destroy_tx1:
1125         b43legacy_destroy_dmaring(dma->tx_ring1);
1126         dma->tx_ring1 = NULL;
1127 err_destroy_tx0:
1128         b43legacy_destroy_dmaring(dma->tx_ring0);
1129         dma->tx_ring0 = NULL;
1130         goto out;
1131 }
1132
1133 /* Generate a cookie for the TX header. */
1134 static u16 generate_cookie(struct b43legacy_dmaring *ring,
1135                            int slot)
1136 {
1137         u16 cookie = 0x1000;
1138
1139         /* Use the upper 4 bits of the cookie as
1140          * DMA controller ID and store the slot number
1141          * in the lower 12 bits.
1142          * Note that the cookie must never be 0, as this
1143          * is a special value used in RX path.
1144          */
1145         switch (ring->index) {
1146         case 0:
1147                 cookie = 0xA000;
1148                 break;
1149         case 1:
1150                 cookie = 0xB000;
1151                 break;
1152         case 2:
1153                 cookie = 0xC000;
1154                 break;
1155         case 3:
1156                 cookie = 0xD000;
1157                 break;
1158         case 4:
1159                 cookie = 0xE000;
1160                 break;
1161         case 5:
1162                 cookie = 0xF000;
1163                 break;
1164         }
1165         B43legacy_WARN_ON(!(((u16)slot & 0xF000) == 0x0000));
1166         cookie |= (u16)slot;
1167
1168         return cookie;
1169 }
1170
1171 /* Inspect a cookie and find out to which controller/slot it belongs. */
1172 static
1173 struct b43legacy_dmaring *parse_cookie(struct b43legacy_wldev *dev,
1174                                       u16 cookie, int *slot)
1175 {
1176         struct b43legacy_dma *dma = &dev->dma;
1177         struct b43legacy_dmaring *ring = NULL;
1178
1179         switch (cookie & 0xF000) {
1180         case 0xA000:
1181                 ring = dma->tx_ring0;
1182                 break;
1183         case 0xB000:
1184                 ring = dma->tx_ring1;
1185                 break;
1186         case 0xC000:
1187                 ring = dma->tx_ring2;
1188                 break;
1189         case 0xD000:
1190                 ring = dma->tx_ring3;
1191                 break;
1192         case 0xE000:
1193                 ring = dma->tx_ring4;
1194                 break;
1195         case 0xF000:
1196                 ring = dma->tx_ring5;
1197                 break;
1198         default:
1199                 B43legacy_WARN_ON(1);
1200         }
1201         *slot = (cookie & 0x0FFF);
1202         B43legacy_WARN_ON(!(ring && *slot >= 0 && *slot < ring->nr_slots));
1203
1204         return ring;
1205 }
1206
1207 static int dma_tx_fragment(struct b43legacy_dmaring *ring,
1208                             struct sk_buff *skb,
1209                             struct ieee80211_tx_control *ctl)
1210 {
1211         const struct b43legacy_dma_ops *ops = ring->ops;
1212         u8 *header;
1213         int slot, old_top_slot, old_used_slots;
1214         int err;
1215         struct b43legacy_dmadesc_generic *desc;
1216         struct b43legacy_dmadesc_meta *meta;
1217         struct b43legacy_dmadesc_meta *meta_hdr;
1218         struct sk_buff *bounce_skb;
1219
1220 #define SLOTS_PER_PACKET  2
1221         B43legacy_WARN_ON(skb_shinfo(skb)->nr_frags != 0);
1222
1223         old_top_slot = ring->current_slot;
1224         old_used_slots = ring->used_slots;
1225
1226         /* Get a slot for the header. */
1227         slot = request_slot(ring);
1228         desc = ops->idx2desc(ring, slot, &meta_hdr);
1229         memset(meta_hdr, 0, sizeof(*meta_hdr));
1230
1231         header = &(ring->txhdr_cache[slot * sizeof(
1232                                struct b43legacy_txhdr_fw3)]);
1233         err = b43legacy_generate_txhdr(ring->dev, header,
1234                                  skb->data, skb->len, ctl,
1235                                  generate_cookie(ring, slot));
1236         if (unlikely(err)) {
1237                 ring->current_slot = old_top_slot;
1238                 ring->used_slots = old_used_slots;
1239                 return err;
1240         }
1241
1242         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1243                                            sizeof(struct b43legacy_txhdr_fw3), 1);
1244         if (b43legacy_dma_mapping_error(ring, meta_hdr->dmaaddr,
1245                                         sizeof(struct b43legacy_txhdr_fw3), 1)) {
1246                 ring->current_slot = old_top_slot;
1247                 ring->used_slots = old_used_slots;
1248                 return -EIO;
1249         }
1250         ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1251                              sizeof(struct b43legacy_txhdr_fw3), 1, 0, 0);
1252
1253         /* Get a slot for the payload. */
1254         slot = request_slot(ring);
1255         desc = ops->idx2desc(ring, slot, &meta);
1256         memset(meta, 0, sizeof(*meta));
1257
1258         memcpy(&meta->txstat.control, ctl, sizeof(*ctl));
1259         meta->skb = skb;
1260         meta->is_last_fragment = 1;
1261
1262         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1263         /* create a bounce buffer in zone_dma on mapping failure. */
1264         if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1265                 bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
1266                 if (!bounce_skb) {
1267                         ring->current_slot = old_top_slot;
1268                         ring->used_slots = old_used_slots;
1269                         err = -ENOMEM;
1270                         goto out_unmap_hdr;
1271                 }
1272
1273                 memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
1274                 dev_kfree_skb_any(skb);
1275                 skb = bounce_skb;
1276                 meta->skb = skb;
1277                 meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1278                 if (b43legacy_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1279                         ring->current_slot = old_top_slot;
1280                         ring->used_slots = old_used_slots;
1281                         err = -EIO;
1282                         goto out_free_bounce;
1283                 }
1284         }
1285
1286         ops->fill_descriptor(ring, desc, meta->dmaaddr,
1287                              skb->len, 0, 1, 1);
1288
1289         wmb();  /* previous stuff MUST be done */
1290         /* Now transfer the whole frame. */
1291         ops->poke_tx(ring, next_slot(ring, slot));
1292         return 0;
1293
1294 out_free_bounce:
1295         dev_kfree_skb_any(skb);
1296 out_unmap_hdr:
1297         unmap_descbuffer(ring, meta_hdr->dmaaddr,
1298                          sizeof(struct b43legacy_txhdr_fw3), 1);
1299         return err;
1300 }
1301
1302 static inline
1303 int should_inject_overflow(struct b43legacy_dmaring *ring)
1304 {
1305 #ifdef CONFIG_B43LEGACY_DEBUG
1306         if (unlikely(b43legacy_debug(ring->dev,
1307                                      B43legacy_DBG_DMAOVERFLOW))) {
1308                 /* Check if we should inject another ringbuffer overflow
1309                  * to test handling of this situation in the stack. */
1310                 unsigned long next_overflow;
1311
1312                 next_overflow = ring->last_injected_overflow + HZ;
1313                 if (time_after(jiffies, next_overflow)) {
1314                         ring->last_injected_overflow = jiffies;
1315                         b43legacydbg(ring->dev->wl,
1316                                "Injecting TX ring overflow on "
1317                                "DMA controller %d\n", ring->index);
1318                         return 1;
1319                 }
1320         }
1321 #endif /* CONFIG_B43LEGACY_DEBUG */
1322         return 0;
1323 }
1324
1325 int b43legacy_dma_tx(struct b43legacy_wldev *dev,
1326                      struct sk_buff *skb,
1327                      struct ieee80211_tx_control *ctl)
1328 {
1329         struct b43legacy_dmaring *ring;
1330         int err = 0;
1331         unsigned long flags;
1332
1333         ring = priority_to_txring(dev, ctl->queue);
1334         spin_lock_irqsave(&ring->lock, flags);
1335         B43legacy_WARN_ON(!ring->tx);
1336         if (unlikely(free_slots(ring) < SLOTS_PER_PACKET)) {
1337                 b43legacywarn(dev->wl, "DMA queue overflow\n");
1338                 err = -ENOSPC;
1339                 goto out_unlock;
1340         }
1341         /* Check if the queue was stopped in mac80211,
1342          * but we got called nevertheless.
1343          * That would be a mac80211 bug. */
1344         B43legacy_BUG_ON(ring->stopped);
1345
1346         err = dma_tx_fragment(ring, skb, ctl);
1347         if (unlikely(err == -ENOKEY)) {
1348                 /* Drop this packet, as we don't have the encryption key
1349                  * anymore and must not transmit it unencrypted. */
1350                 dev_kfree_skb_any(skb);
1351                 err = 0;
1352                 goto out_unlock;
1353         }
1354         if (unlikely(err)) {
1355                 b43legacyerr(dev->wl, "DMA tx mapping failure\n");
1356                 goto out_unlock;
1357         }
1358         ring->nr_tx_packets++;
1359         if ((free_slots(ring) < SLOTS_PER_PACKET) ||
1360             should_inject_overflow(ring)) {
1361                 /* This TX ring is full. */
1362                 ieee80211_stop_queue(dev->wl->hw, txring_to_priority(ring));
1363                 ring->stopped = 1;
1364                 if (b43legacy_debug(dev, B43legacy_DBG_DMAVERBOSE))
1365                         b43legacydbg(dev->wl, "Stopped TX ring %d\n",
1366                                ring->index);
1367         }
1368 out_unlock:
1369         spin_unlock_irqrestore(&ring->lock, flags);
1370
1371         return err;
1372 }
1373
1374 void b43legacy_dma_handle_txstatus(struct b43legacy_wldev *dev,
1375                                  const struct b43legacy_txstatus *status)
1376 {
1377         const struct b43legacy_dma_ops *ops;
1378         struct b43legacy_dmaring *ring;
1379         struct b43legacy_dmadesc_generic *desc;
1380         struct b43legacy_dmadesc_meta *meta;
1381         int slot;
1382
1383         ring = parse_cookie(dev, status->cookie, &slot);
1384         if (unlikely(!ring))
1385                 return;
1386         B43legacy_WARN_ON(!irqs_disabled());
1387         spin_lock(&ring->lock);
1388
1389         B43legacy_WARN_ON(!ring->tx);
1390         ops = ring->ops;
1391         while (1) {
1392                 B43legacy_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
1393                 desc = ops->idx2desc(ring, slot, &meta);
1394
1395                 if (meta->skb)
1396                         unmap_descbuffer(ring, meta->dmaaddr,
1397                                          meta->skb->len, 1);
1398                 else
1399                         unmap_descbuffer(ring, meta->dmaaddr,
1400                                          sizeof(struct b43legacy_txhdr_fw3),
1401                                          1);
1402
1403                 if (meta->is_last_fragment) {
1404                         B43legacy_WARN_ON(!meta->skb);
1405                         /* Call back to inform the ieee80211 subsystem about the
1406                          * status of the transmission.
1407                          * Some fields of txstat are already filled in dma_tx().
1408                          */
1409                         if (status->acked) {
1410                                 meta->txstat.flags |= IEEE80211_TX_STATUS_ACK;
1411                         } else {
1412                                 if (!(meta->txstat.control.flags
1413                                       & IEEE80211_TXCTL_NO_ACK))
1414                                          meta->txstat.excessive_retries = 1;
1415                         }
1416                         if (status->frame_count == 0) {
1417                                 /* The frame was not transmitted at all. */
1418                                 meta->txstat.retry_count = 0;
1419                         } else
1420                                 meta->txstat.retry_count = status->frame_count
1421                                                            - 1;
1422                         ieee80211_tx_status_irqsafe(dev->wl->hw, meta->skb,
1423                                                     &(meta->txstat));
1424                         /* skb is freed by ieee80211_tx_status_irqsafe() */
1425                         meta->skb = NULL;
1426                 } else {
1427                         /* No need to call free_descriptor_buffer here, as
1428                          * this is only the txhdr, which is not allocated.
1429                          */
1430                         B43legacy_WARN_ON(meta->skb != NULL);
1431                 }
1432
1433                 /* Everything unmapped and free'd. So it's not used anymore. */
1434                 ring->used_slots--;
1435
1436                 if (meta->is_last_fragment)
1437                         break;
1438                 slot = next_slot(ring, slot);
1439         }
1440         dev->stats.last_tx = jiffies;
1441         if (ring->stopped) {
1442                 B43legacy_WARN_ON(free_slots(ring) < SLOTS_PER_PACKET);
1443                 ieee80211_wake_queue(dev->wl->hw, txring_to_priority(ring));
1444                 ring->stopped = 0;
1445                 if (b43legacy_debug(dev, B43legacy_DBG_DMAVERBOSE))
1446                         b43legacydbg(dev->wl, "Woke up TX ring %d\n",
1447                                ring->index);
1448         }
1449
1450         spin_unlock(&ring->lock);
1451 }
1452
1453 void b43legacy_dma_get_tx_stats(struct b43legacy_wldev *dev,
1454                               struct ieee80211_tx_queue_stats *stats)
1455 {
1456         const int nr_queues = dev->wl->hw->queues;
1457         struct b43legacy_dmaring *ring;
1458         struct ieee80211_tx_queue_stats_data *data;
1459         unsigned long flags;
1460         int i;
1461
1462         for (i = 0; i < nr_queues; i++) {
1463                 data = &(stats->data[i]);
1464                 ring = priority_to_txring(dev, i);
1465
1466                 spin_lock_irqsave(&ring->lock, flags);
1467                 data->len = ring->used_slots / SLOTS_PER_PACKET;
1468                 data->limit = ring->nr_slots / SLOTS_PER_PACKET;
1469                 data->count = ring->nr_tx_packets;
1470                 spin_unlock_irqrestore(&ring->lock, flags);
1471         }
1472 }
1473
1474 static void dma_rx(struct b43legacy_dmaring *ring,
1475                    int *slot)
1476 {
1477         const struct b43legacy_dma_ops *ops = ring->ops;
1478         struct b43legacy_dmadesc_generic *desc;
1479         struct b43legacy_dmadesc_meta *meta;
1480         struct b43legacy_rxhdr_fw3 *rxhdr;
1481         struct sk_buff *skb;
1482         u16 len;
1483         int err;
1484         dma_addr_t dmaaddr;
1485
1486         desc = ops->idx2desc(ring, *slot, &meta);
1487
1488         sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1489         skb = meta->skb;
1490
1491         if (ring->index == 3) {
1492                 /* We received an xmit status. */
1493                 struct b43legacy_hwtxstatus *hw =
1494                                 (struct b43legacy_hwtxstatus *)skb->data;
1495                 int i = 0;
1496
1497                 while (hw->cookie == 0) {
1498                         if (i > 100)
1499                                 break;
1500                         i++;
1501                         udelay(2);
1502                         barrier();
1503                 }
1504                 b43legacy_handle_hwtxstatus(ring->dev, hw);
1505                 /* recycle the descriptor buffer. */
1506                 sync_descbuffer_for_device(ring, meta->dmaaddr,
1507                                            ring->rx_buffersize);
1508
1509                 return;
1510         }
1511         rxhdr = (struct b43legacy_rxhdr_fw3 *)skb->data;
1512         len = le16_to_cpu(rxhdr->frame_len);
1513         if (len == 0) {
1514                 int i = 0;
1515
1516                 do {
1517                         udelay(2);
1518                         barrier();
1519                         len = le16_to_cpu(rxhdr->frame_len);
1520                 } while (len == 0 && i++ < 5);
1521                 if (unlikely(len == 0)) {
1522                         /* recycle the descriptor buffer. */
1523                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1524                                                    ring->rx_buffersize);
1525                         goto drop;
1526                 }
1527         }
1528         if (unlikely(len > ring->rx_buffersize)) {
1529                 /* The data did not fit into one descriptor buffer
1530                  * and is split over multiple buffers.
1531                  * This should never happen, as we try to allocate buffers
1532                  * big enough. So simply ignore this packet.
1533                  */
1534                 int cnt = 0;
1535                 s32 tmp = len;
1536
1537                 while (1) {
1538                         desc = ops->idx2desc(ring, *slot, &meta);
1539                         /* recycle the descriptor buffer. */
1540                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1541                                                    ring->rx_buffersize);
1542                         *slot = next_slot(ring, *slot);
1543                         cnt++;
1544                         tmp -= ring->rx_buffersize;
1545                         if (tmp <= 0)
1546                                 break;
1547                 }
1548                 b43legacyerr(ring->dev->wl, "DMA RX buffer too small "
1549                        "(len: %u, buffer: %u, nr-dropped: %d)\n",
1550                        len, ring->rx_buffersize, cnt);
1551                 goto drop;
1552         }
1553
1554         dmaaddr = meta->dmaaddr;
1555         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1556         if (unlikely(err)) {
1557                 b43legacydbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer()"
1558                              " failed\n");
1559                 sync_descbuffer_for_device(ring, dmaaddr,
1560                                            ring->rx_buffersize);
1561                 goto drop;
1562         }
1563
1564         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1565         skb_put(skb, len + ring->frameoffset);
1566         skb_pull(skb, ring->frameoffset);
1567
1568         b43legacy_rx(ring->dev, skb, rxhdr);
1569 drop:
1570         return;
1571 }
1572
1573 void b43legacy_dma_rx(struct b43legacy_dmaring *ring)
1574 {
1575         const struct b43legacy_dma_ops *ops = ring->ops;
1576         int slot;
1577         int current_slot;
1578         int used_slots = 0;
1579
1580         B43legacy_WARN_ON(ring->tx);
1581         current_slot = ops->get_current_rxslot(ring);
1582         B43legacy_WARN_ON(!(current_slot >= 0 && current_slot <
1583                            ring->nr_slots));
1584
1585         slot = ring->current_slot;
1586         for (; slot != current_slot; slot = next_slot(ring, slot)) {
1587                 dma_rx(ring, &slot);
1588                 update_max_used_slots(ring, ++used_slots);
1589         }
1590         ops->set_current_rxslot(ring, slot);
1591         ring->current_slot = slot;
1592 }
1593
1594 static void b43legacy_dma_tx_suspend_ring(struct b43legacy_dmaring *ring)
1595 {
1596         unsigned long flags;
1597
1598         spin_lock_irqsave(&ring->lock, flags);
1599         B43legacy_WARN_ON(!ring->tx);
1600         ring->ops->tx_suspend(ring);
1601         spin_unlock_irqrestore(&ring->lock, flags);
1602 }
1603
1604 static void b43legacy_dma_tx_resume_ring(struct b43legacy_dmaring *ring)
1605 {
1606         unsigned long flags;
1607
1608         spin_lock_irqsave(&ring->lock, flags);
1609         B43legacy_WARN_ON(!ring->tx);
1610         ring->ops->tx_resume(ring);
1611         spin_unlock_irqrestore(&ring->lock, flags);
1612 }
1613
1614 void b43legacy_dma_tx_suspend(struct b43legacy_wldev *dev)
1615 {
1616         b43legacy_power_saving_ctl_bits(dev, -1, 1);
1617         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring0);
1618         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring1);
1619         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring2);
1620         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring3);
1621         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring4);
1622         b43legacy_dma_tx_suspend_ring(dev->dma.tx_ring5);
1623 }
1624
1625 void b43legacy_dma_tx_resume(struct b43legacy_wldev *dev)
1626 {
1627         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring5);
1628         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring4);
1629         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring3);
1630         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring2);
1631         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring1);
1632         b43legacy_dma_tx_resume_ring(dev->dma.tx_ring0);
1633         b43legacy_power_saving_ctl_bits(dev, -1, -1);
1634 }