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 #include <linux/slab.h>
  42 #include <asm/div64.h>
  43
  44
  45 /* Required number of TX DMA slots per TX frame.
  46  * This currently is 2, because we put the header and the ieee80211 frame
  47  * into separate slots. */
  48 #define TX_SLOTS_PER_FRAME      2
  49
  50
  51 /* 32bit DMA ops. */
  52 static
  53 struct b43_dmadesc_generic *op32_idx2desc(struct b43_dmaring *ring,
  54                                           int slot,
  55                                           struct b43_dmadesc_meta **meta)
  56 {
  57         struct b43_dmadesc32 *desc;
  58
  59         *meta = &(ring->meta[slot]);
  60         desc = ring->descbase;
  61         desc = &(desc[slot]);
  62
  63         return (struct b43_dmadesc_generic *)desc;
  64 }
  65
  66 static void op32_fill_descriptor(struct b43_dmaring *ring,
  67                                  struct b43_dmadesc_generic *desc,
  68                                  dma_addr_t dmaaddr, u16 bufsize,
  69                                  int start, int end, int irq)
  70 {
  71         struct b43_dmadesc32 *descbase = ring->descbase;
  72         int slot;
  73         u32 ctl;
  74         u32 addr;
  75         u32 addrext;
  76
  77         slot = (int)(&(desc->dma32) - descbase);
  78         B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
  79
  80         addr = (u32) (dmaaddr & ~SSB_DMA_TRANSLATION_MASK);
  81         addrext = (u32) (dmaaddr & SSB_DMA_TRANSLATION_MASK)
  82             >> SSB_DMA_TRANSLATION_SHIFT;
  83         addr |= ssb_dma_translation(ring->dev->dev);
  84         ctl = bufsize & B43_DMA32_DCTL_BYTECNT;
  85         if (slot == ring->nr_slots - 1)
  86                 ctl |= B43_DMA32_DCTL_DTABLEEND;
  87         if (start)
  88                 ctl |= B43_DMA32_DCTL_FRAMESTART;
  89         if (end)
  90                 ctl |= B43_DMA32_DCTL_FRAMEEND;
  91         if (irq)
  92                 ctl |= B43_DMA32_DCTL_IRQ;
  93         ctl |= (addrext << B43_DMA32_DCTL_ADDREXT_SHIFT)
  94             & B43_DMA32_DCTL_ADDREXT_MASK;
  95
  96         desc->dma32.control = cpu_to_le32(ctl);
  97         desc->dma32.address = cpu_to_le32(addr);
  98 }
  99
 100 static void op32_poke_tx(struct b43_dmaring *ring, int slot)
 101 {
 102         b43_dma_write(ring, B43_DMA32_TXINDEX,
 103                       (u32) (slot * sizeof(struct b43_dmadesc32)));
 104 }
 105
 106 static void op32_tx_suspend(struct b43_dmaring *ring)
 107 {
 108         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 109                       | B43_DMA32_TXSUSPEND);
 110 }
 111
 112 static void op32_tx_resume(struct b43_dmaring *ring)
 113 {
 114         b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 115                       & ~B43_DMA32_TXSUSPEND);
 116 }
 117
 118 static int op32_get_current_rxslot(struct b43_dmaring *ring)
 119 {
 120         u32 val;
 121
 122         val = b43_dma_read(ring, B43_DMA32_RXSTATUS);
 123         val &= B43_DMA32_RXDPTR;
 124
 125         return (val / sizeof(struct b43_dmadesc32));
 126 }
 127
 128 static void op32_set_current_rxslot(struct b43_dmaring *ring, int slot)
 129 {
 130         b43_dma_write(ring, B43_DMA32_RXINDEX,
 131                       (u32) (slot * sizeof(struct b43_dmadesc32)));
 132 }
 133
 134 static const struct b43_dma_ops dma32_ops = {
 135         .idx2desc = op32_idx2desc,
 136         .fill_descriptor = op32_fill_descriptor,
 137         .poke_tx = op32_poke_tx,
 138         .tx_suspend = op32_tx_suspend,
 139         .tx_resume = op32_tx_resume,
 140         .get_current_rxslot = op32_get_current_rxslot,
 141         .set_current_rxslot = op32_set_current_rxslot,
 142 };
 143
 144 /* 64bit DMA ops. */
 145 static
 146 struct b43_dmadesc_generic *op64_idx2desc(struct b43_dmaring *ring,
 147                                           int slot,
 148                                           struct b43_dmadesc_meta **meta)
 149 {
 150         struct b43_dmadesc64 *desc;
 151
 152         *meta = &(ring->meta[slot]);
 153         desc = ring->descbase;
 154         desc = &(desc[slot]);
 155
 156         return (struct b43_dmadesc_generic *)desc;
 157 }
 158
 159 static void op64_fill_descriptor(struct b43_dmaring *ring,
 160                                  struct b43_dmadesc_generic *desc,
 161                                  dma_addr_t dmaaddr, u16 bufsize,
 162                                  int start, int end, int irq)
 163 {
 164         struct b43_dmadesc64 *descbase = ring->descbase;
 165         int slot;
 166         u32 ctl0 = 0, ctl1 = 0;
 167         u32 addrlo, addrhi;
 168         u32 addrext;
 169
 170         slot = (int)(&(desc->dma64) - descbase);
 171         B43_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) << 1);
 178         if (slot == ring->nr_slots - 1)
 179                 ctl0 |= B43_DMA64_DCTL0_DTABLEEND;
 180         if (start)
 181                 ctl0 |= B43_DMA64_DCTL0_FRAMESTART;
 182         if (end)
 183                 ctl0 |= B43_DMA64_DCTL0_FRAMEEND;
 184         if (irq)
 185                 ctl0 |= B43_DMA64_DCTL0_IRQ;
 186         ctl1 |= bufsize & B43_DMA64_DCTL1_BYTECNT;
 187         ctl1 |= (addrext << B43_DMA64_DCTL1_ADDREXT_SHIFT)
 188             & B43_DMA64_DCTL1_ADDREXT_MASK;
 189
 190         desc->dma64.control0 = cpu_to_le32(ctl0);
 191         desc->dma64.control1 = cpu_to_le32(ctl1);
 192         desc->dma64.address_low = cpu_to_le32(addrlo);
 193         desc->dma64.address_high = cpu_to_le32(addrhi);
 194 }
 195
 196 static void op64_poke_tx(struct b43_dmaring *ring, int slot)
 197 {
 198         b43_dma_write(ring, B43_DMA64_TXINDEX,
 199                       (u32) (slot * sizeof(struct b43_dmadesc64)));
 200 }
 201
 202 static void op64_tx_suspend(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 void op64_tx_resume(struct b43_dmaring *ring)
 209 {
 210         b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
 211                       & ~B43_DMA64_TXSUSPEND);
 212 }
 213
 214 static int op64_get_current_rxslot(struct b43_dmaring *ring)
 215 {
 216         u32 val;
 217
 218         val = b43_dma_read(ring, B43_DMA64_RXSTATUS);
 219         val &= B43_DMA64_RXSTATDPTR;
 220
 221         return (val / sizeof(struct b43_dmadesc64));
 222 }
 223
 224 static void op64_set_current_rxslot(struct b43_dmaring *ring, int slot)
 225 {
 226         b43_dma_write(ring, B43_DMA64_RXINDEX,
 227                       (u32) (slot * sizeof(struct b43_dmadesc64)));
 228 }
 229
 230 static const struct b43_dma_ops dma64_ops = {
 231         .idx2desc = op64_idx2desc,
 232         .fill_descriptor = op64_fill_descriptor,
 233         .poke_tx = op64_poke_tx,
 234         .tx_suspend = op64_tx_suspend,
 235         .tx_resume = op64_tx_resume,
 236         .get_current_rxslot = op64_get_current_rxslot,
 237         .set_current_rxslot = op64_set_current_rxslot,
 238 };
 239
 240 static inline int free_slots(struct b43_dmaring *ring)
 241 {
 242         return (ring->nr_slots - ring->used_slots);
 243 }
 244
 245 static inline int next_slot(struct b43_dmaring *ring, int slot)
 246 {
 247         B43_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
 248         if (slot == ring->nr_slots - 1)
 249                 return 0;
 250         return slot + 1;
 251 }
 252
 253 static inline int prev_slot(struct b43_dmaring *ring, int slot)
 254 {
 255         B43_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
 256         if (slot == 0)
 257                 return ring->nr_slots - 1;
 258         return slot - 1;
 259 }
 260
 261 #ifdef CONFIG_B43_DEBUG
 262 static void update_max_used_slots(struct b43_dmaring *ring,
 263                                   int current_used_slots)
 264 {
 265         if (current_used_slots <= ring->max_used_slots)
 266                 return;
 267         ring->max_used_slots = current_used_slots;
 268         if (b43_debug(ring->dev, B43_DBG_DMAVERBOSE)) {
 269                 b43dbg(ring->dev->wl,
 270                        "max_used_slots increased to %d on %s ring %d\n",
 271                        ring->max_used_slots,
 272                        ring->tx ? "TX" : "RX", ring->index);
 273         }
 274 }
 275 #else
 276 static inline
 277     void update_max_used_slots(struct b43_dmaring *ring, int current_used_slots)
 278 {
 279 }
 280 #endif /* DEBUG */
 281
 282 /* Request a slot for usage. */
 283 static inline int request_slot(struct b43_dmaring *ring)
 284 {
 285         int slot;
 286
 287         B43_WARN_ON(!ring->tx);
 288         B43_WARN_ON(ring->stopped);
 289         B43_WARN_ON(free_slots(ring) == 0);
 290
 291         slot = next_slot(ring, ring->current_slot);
 292         ring->current_slot = slot;
 293         ring->used_slots++;
 294
 295         update_max_used_slots(ring, ring->used_slots);
 296
 297         return slot;
 298 }
 299
 300 static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
 301 {
 302         static const u16 map64[] = {
 303                 B43_MMIO_DMA64_BASE0,
 304                 B43_MMIO_DMA64_BASE1,
 305                 B43_MMIO_DMA64_BASE2,
 306                 B43_MMIO_DMA64_BASE3,
 307                 B43_MMIO_DMA64_BASE4,
 308                 B43_MMIO_DMA64_BASE5,
 309         };
 310         static const u16 map32[] = {
 311                 B43_MMIO_DMA32_BASE0,
 312                 B43_MMIO_DMA32_BASE1,
 313                 B43_MMIO_DMA32_BASE2,
 314                 B43_MMIO_DMA32_BASE3,
 315                 B43_MMIO_DMA32_BASE4,
 316                 B43_MMIO_DMA32_BASE5,
 317         };
 318
 319         if (type == B43_DMA_64BIT) {
 320                 B43_WARN_ON(!(controller_idx >= 0 &&
 321                               controller_idx < ARRAY_SIZE(map64)));
 322                 return map64[controller_idx];
 323         }
 324         B43_WARN_ON(!(controller_idx >= 0 &&
 325                       controller_idx < ARRAY_SIZE(map32)));
 326         return map32[controller_idx];
 327 }
 328
 329 static inline
 330     dma_addr_t map_descbuffer(struct b43_dmaring *ring,
 331                               unsigned char *buf, size_t len, int tx)
 332 {
 333         dma_addr_t dmaaddr;
 334
 335         if (tx) {
 336                 dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 337                                          buf, len, DMA_TO_DEVICE);
 338         } else {
 339                 dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 340                                          buf, len, DMA_FROM_DEVICE);
 341         }
 342
 343         return dmaaddr;
 344 }
 345
 346 static inline
 347     void unmap_descbuffer(struct b43_dmaring *ring,
 348                           dma_addr_t addr, size_t len, int tx)
 349 {
 350         if (tx) {
 351                 dma_unmap_single(ring->dev->dev->dma_dev,
 352                                  addr, len, DMA_TO_DEVICE);
 353         } else {
 354                 dma_unmap_single(ring->dev->dev->dma_dev,
 355                                  addr, len, DMA_FROM_DEVICE);
 356         }
 357 }
 358
 359 static inline
 360     void sync_descbuffer_for_cpu(struct b43_dmaring *ring,
 361                                  dma_addr_t addr, size_t len)
 362 {
 363         B43_WARN_ON(ring->tx);
 364         dma_sync_single_for_cpu(ring->dev->dev->dma_dev,
 365                                     addr, len, DMA_FROM_DEVICE);
 366 }
 367
 368 static inline
 369     void sync_descbuffer_for_device(struct b43_dmaring *ring,
 370                                     dma_addr_t addr, size_t len)
 371 {
 372         B43_WARN_ON(ring->tx);
 373         dma_sync_single_for_device(ring->dev->dev->dma_dev,
 374                                    addr, len, DMA_FROM_DEVICE);
 375 }
 376
 377 static inline
 378     void free_descriptor_buffer(struct b43_dmaring *ring,
 379                                 struct b43_dmadesc_meta *meta)
 380 {
 381         if (meta->skb) {
 382                 dev_kfree_skb_any(meta->skb);
 383                 meta->skb = NULL;
 384         }
 385 }
 386
 387 static int alloc_ringmemory(struct b43_dmaring *ring)
 388 {
 389         gfp_t flags = GFP_KERNEL;
 390
 391         /* The specs call for 4K buffers for 30- and 32-bit DMA with 4K
 392          * alignment and 8K buffers for 64-bit DMA with 8K alignment. Testing
 393          * has shown that 4K is sufficient for the latter as long as the buffer
 394          * does not cross an 8K boundary.
 395          *
 396          * For unknown reasons - possibly a hardware error - the BCM4311 rev
 397          * 02, which uses 64-bit DMA, needs the ring buffer in very low memory,
 398          * which accounts for the GFP_DMA flag below.
 399          *
 400          * The flags here must match the flags in free_ringmemory below!
 401          */
 402         if (ring->type == B43_DMA_64BIT)
 403                 flags |= GFP_DMA;
 404         ring->descbase = dma_alloc_coherent(ring->dev->dev->dma_dev,
 405                                             B43_DMA_RINGMEMSIZE,
 406                                             &(ring->dmabase), flags);
 407         if (!ring->descbase) {
 408                 b43err(ring->dev->wl, "DMA ringmemory allocation failed\n");
 409                 return -ENOMEM;
 410         }
 411         memset(ring->descbase, 0, B43_DMA_RINGMEMSIZE);
 412
 413         return 0;
 414 }
 415
 416 static void free_ringmemory(struct b43_dmaring *ring)
 417 {
 418         dma_free_coherent(ring->dev->dev->dma_dev, B43_DMA_RINGMEMSIZE,
 419                           ring->descbase, ring->dmabase);
 420 }
 421
 422 /* Reset the RX DMA channel */
 423 static int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base,
 424                                       enum b43_dmatype type)
 425 {
 426         int i;
 427         u32 value;
 428         u16 offset;
 429
 430         might_sleep();
 431
 432         offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
 433         b43_write32(dev, mmio_base + offset, 0);
 434         for (i = 0; i < 10; i++) {
 435                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXSTATUS :
 436                                                    B43_DMA32_RXSTATUS;
 437                 value = b43_read32(dev, mmio_base + offset);
 438                 if (type == B43_DMA_64BIT) {
 439                         value &= B43_DMA64_RXSTAT;
 440                         if (value == B43_DMA64_RXSTAT_DISABLED) {
 441                                 i = -1;
 442                                 break;
 443                         }
 444                 } else {
 445                         value &= B43_DMA32_RXSTATE;
 446                         if (value == B43_DMA32_RXSTAT_DISABLED) {
 447                                 i = -1;
 448                                 break;
 449                         }
 450                 }
 451                 msleep(1);
 452         }
 453         if (i != -1) {
 454                 b43err(dev->wl, "DMA RX reset timed out\n");
 455                 return -ENODEV;
 456         }
 457
 458         return 0;
 459 }
 460
 461 /* Reset the TX DMA channel */
 462 static int b43_dmacontroller_tx_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         for (i = 0; i < 10; i++) {
 472                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 473                                                    B43_DMA32_TXSTATUS;
 474                 value = b43_read32(dev, mmio_base + offset);
 475                 if (type == B43_DMA_64BIT) {
 476                         value &= B43_DMA64_TXSTAT;
 477                         if (value == B43_DMA64_TXSTAT_DISABLED ||
 478                             value == B43_DMA64_TXSTAT_IDLEWAIT ||
 479                             value == B43_DMA64_TXSTAT_STOPPED)
 480                                 break;
 481                 } else {
 482                         value &= B43_DMA32_TXSTATE;
 483                         if (value == B43_DMA32_TXSTAT_DISABLED ||
 484                             value == B43_DMA32_TXSTAT_IDLEWAIT ||
 485                             value == B43_DMA32_TXSTAT_STOPPED)
 486                                 break;
 487                 }
 488                 msleep(1);
 489         }
 490         offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
 491         b43_write32(dev, mmio_base + offset, 0);
 492         for (i = 0; i < 10; i++) {
 493                 offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 494                                                    B43_DMA32_TXSTATUS;
 495                 value = b43_read32(dev, mmio_base + offset);
 496                 if (type == B43_DMA_64BIT) {
 497                         value &= B43_DMA64_TXSTAT;
 498                         if (value == B43_DMA64_TXSTAT_DISABLED) {
 499                                 i = -1;
 500                                 break;
 501                         }
 502                 } else {
 503                         value &= B43_DMA32_TXSTATE;
 504                         if (value == B43_DMA32_TXSTAT_DISABLED) {
 505                                 i = -1;
 506                                 break;
 507                         }
 508                 }
 509                 msleep(1);
 510         }
 511         if (i != -1) {
 512                 b43err(dev->wl, "DMA TX reset timed out\n");
 513                 return -ENODEV;
 514         }
 515         /* ensure the reset is completed. */
 516         msleep(1);
 517
 518         return 0;
 519 }
 520
 521 /* Check if a DMA mapping address is invalid. */
 522 static bool b43_dma_mapping_error(struct b43_dmaring *ring,
 523                                   dma_addr_t addr,
 524                                   size_t buffersize, bool dma_to_device)
 525 {
 526         if (unlikely(dma_mapping_error(ring->dev->dev->dma_dev, addr)))
 527                 return 1;
 528
 529         switch (ring->type) {
 530         case B43_DMA_30BIT:
 531                 if ((u64)addr + buffersize > (1ULL << 30))
 532                         goto address_error;
 533                 break;
 534         case B43_DMA_32BIT:
 535                 if ((u64)addr + buffersize > (1ULL << 32))
 536                         goto address_error;
 537                 break;
 538         case B43_DMA_64BIT:
 539                 /* Currently we can't have addresses beyond
 540                  * 64bit in the kernel. */
 541                 break;
 542         }
 543
 544         /* The address is OK. */
 545         return 0;
 546
 547 address_error:
 548         /* We can't support this address. Unmap it again. */
 549         unmap_descbuffer(ring, addr, buffersize, dma_to_device);
 550
 551         return 1;
 552 }
 553
 554 static bool b43_rx_buffer_is_poisoned(struct b43_dmaring *ring, struct sk_buff *skb)
 555 {
 556         unsigned char *f = skb->data + ring->frameoffset;
 557
 558         return ((f[0] & f[1] & f[2] & f[3] & f[4] & f[5] & f[6] & f[7]) == 0xFF);
 559 }
 560
 561 static void b43_poison_rx_buffer(struct b43_dmaring *ring, struct sk_buff *skb)
 562 {
 563         struct b43_rxhdr_fw4 *rxhdr;
 564         unsigned char *frame;
 565
 566         /* This poisons the RX buffer to detect DMA failures. */
 567
 568         rxhdr = (struct b43_rxhdr_fw4 *)(skb->data);
 569         rxhdr->frame_len = 0;
 570
 571         B43_WARN_ON(ring->rx_buffersize < ring->frameoffset + sizeof(struct b43_plcp_hdr6) + 2);
 572         frame = skb->data + ring->frameoffset;
 573         memset(frame, 0xFF, sizeof(struct b43_plcp_hdr6) + 2 /* padding */);
 574 }
 575
 576 static int setup_rx_descbuffer(struct b43_dmaring *ring,
 577                                struct b43_dmadesc_generic *desc,
 578                                struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
 579 {
 580         dma_addr_t dmaaddr;
 581         struct sk_buff *skb;
 582
 583         B43_WARN_ON(ring->tx);
 584
 585         skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 586         if (unlikely(!skb))
 587                 return -ENOMEM;
 588         b43_poison_rx_buffer(ring, skb);
 589         dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
 590         if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 591                 /* ugh. try to realloc in zone_dma */
 592                 gfp_flags |= GFP_DMA;
 593
 594                 dev_kfree_skb_any(skb);
 595
 596                 skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 597                 if (unlikely(!skb))
 598                         return -ENOMEM;
 599                 b43_poison_rx_buffer(ring, skb);
 600                 dmaaddr = map_descbuffer(ring, skb->data,
 601                                          ring->rx_buffersize, 0);
 602                 if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 603                         b43err(ring->dev->wl, "RX DMA buffer allocation failed\n");
 604                         dev_kfree_skb_any(skb);
 605                         return -EIO;
 606                 }
 607         }
 608
 609         meta->skb = skb;
 610         meta->dmaaddr = dmaaddr;
 611         ring->ops->fill_descriptor(ring, desc, dmaaddr,
 612                                    ring->rx_buffersize, 0, 0, 0);
 613
 614         return 0;
 615 }
 616
 617 /* Allocate the initial descbuffers.
 618  * This is used for an RX ring only.
 619  */
 620 static int alloc_initial_descbuffers(struct b43_dmaring *ring)
 621 {
 622         int i, err = -ENOMEM;
 623         struct b43_dmadesc_generic *desc;
 624         struct b43_dmadesc_meta *meta;
 625
 626         for (i = 0; i < ring->nr_slots; i++) {
 627                 desc = ring->ops->idx2desc(ring, i, &meta);
 628
 629                 err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
 630                 if (err) {
 631                         b43err(ring->dev->wl,
 632                                "Failed to allocate initial descbuffers\n");
 633                         goto err_unwind;
 634                 }
 635         }
 636         mb();
 637         ring->used_slots = ring->nr_slots;
 638         err = 0;
 639       out:
 640         return err;
 641
 642       err_unwind:
 643         for (i--; i >= 0; i--) {
 644                 desc = ring->ops->idx2desc(ring, i, &meta);
 645
 646                 unmap_descbuffer(ring, meta->dmaaddr, ring->rx_buffersize, 0);
 647                 dev_kfree_skb(meta->skb);
 648         }
 649         goto out;
 650 }
 651
 652 /* Do initial setup of the DMA controller.
 653  * Reset the controller, write the ring busaddress
 654  * and switch the "enable" bit on.
 655  */
 656 static int dmacontroller_setup(struct b43_dmaring *ring)
 657 {
 658         int err = 0;
 659         u32 value;
 660         u32 addrext;
 661         u32 trans = ssb_dma_translation(ring->dev->dev);
 662
 663         if (ring->tx) {
 664                 if (ring->type == B43_DMA_64BIT) {
 665                         u64 ringbase = (u64) (ring->dmabase);
 666
 667                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 668                             >> SSB_DMA_TRANSLATION_SHIFT;
 669                         value = B43_DMA64_TXENABLE;
 670                         value |= (addrext << B43_DMA64_TXADDREXT_SHIFT)
 671                             & B43_DMA64_TXADDREXT_MASK;
 672                         b43_dma_write(ring, B43_DMA64_TXCTL, value);
 673                         b43_dma_write(ring, B43_DMA64_TXRINGLO,
 674                                       (ringbase & 0xFFFFFFFF));
 675                         b43_dma_write(ring, B43_DMA64_TXRINGHI,
 676                                       ((ringbase >> 32) &
 677                                        ~SSB_DMA_TRANSLATION_MASK)
 678                                       | (trans << 1));
 679                 } else {
 680                         u32 ringbase = (u32) (ring->dmabase);
 681
 682                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 683                             >> SSB_DMA_TRANSLATION_SHIFT;
 684                         value = B43_DMA32_TXENABLE;
 685                         value |= (addrext << B43_DMA32_TXADDREXT_SHIFT)
 686                             & B43_DMA32_TXADDREXT_MASK;
 687                         b43_dma_write(ring, B43_DMA32_TXCTL, value);
 688                         b43_dma_write(ring, B43_DMA32_TXRING,
 689                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 690                                       | trans);
 691                 }
 692         } else {
 693                 err = alloc_initial_descbuffers(ring);
 694                 if (err)
 695                         goto out;
 696                 if (ring->type == B43_DMA_64BIT) {
 697                         u64 ringbase = (u64) (ring->dmabase);
 698
 699                         addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 700                             >> SSB_DMA_TRANSLATION_SHIFT;
 701                         value = (ring->frameoffset << B43_DMA64_RXFROFF_SHIFT);
 702                         value |= B43_DMA64_RXENABLE;
 703                         value |= (addrext << B43_DMA64_RXADDREXT_SHIFT)
 704                             & B43_DMA64_RXADDREXT_MASK;
 705                         b43_dma_write(ring, B43_DMA64_RXCTL, value);
 706                         b43_dma_write(ring, B43_DMA64_RXRINGLO,
 707                                       (ringbase & 0xFFFFFFFF));
 708                         b43_dma_write(ring, B43_DMA64_RXRINGHI,
 709                                       ((ringbase >> 32) &
 710                                        ~SSB_DMA_TRANSLATION_MASK)
 711                                       | (trans << 1));
 712                         b43_dma_write(ring, B43_DMA64_RXINDEX, ring->nr_slots *
 713                                       sizeof(struct b43_dmadesc64));
 714                 } else {
 715                         u32 ringbase = (u32) (ring->dmabase);
 716
 717                         addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 718                             >> SSB_DMA_TRANSLATION_SHIFT;
 719                         value = (ring->frameoffset << B43_DMA32_RXFROFF_SHIFT);
 720                         value |= B43_DMA32_RXENABLE;
 721                         value |= (addrext << B43_DMA32_RXADDREXT_SHIFT)
 722                             & B43_DMA32_RXADDREXT_MASK;
 723                         b43_dma_write(ring, B43_DMA32_RXCTL, value);
 724                         b43_dma_write(ring, B43_DMA32_RXRING,
 725                                       (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 726                                       | trans);
 727                         b43_dma_write(ring, B43_DMA32_RXINDEX, ring->nr_slots *
 728                                       sizeof(struct b43_dmadesc32));
 729                 }
 730         }
 731
 732 out:
 733         return err;
 734 }
 735
 736 /* Shutdown the DMA controller. */
 737 static void dmacontroller_cleanup(struct b43_dmaring *ring)
 738 {
 739         if (ring->tx) {
 740                 b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
 741                                            ring->type);
 742                 if (ring->type == B43_DMA_64BIT) {
 743                         b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
 744                         b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
 745                 } else
 746                         b43_dma_write(ring, B43_DMA32_TXRING, 0);
 747         } else {
 748                 b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
 749                                            ring->type);
 750                 if (ring->type == B43_DMA_64BIT) {
 751                         b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
 752                         b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
 753                 } else
 754                         b43_dma_write(ring, B43_DMA32_RXRING, 0);
 755         }
 756 }
 757
 758 static void free_all_descbuffers(struct b43_dmaring *ring)
 759 {
 760         struct b43_dmadesc_generic *desc;
 761         struct b43_dmadesc_meta *meta;
 762         int i;
 763
 764         if (!ring->used_slots)
 765                 return;
 766         for (i = 0; i < ring->nr_slots; i++) {
 767                 desc = ring->ops->idx2desc(ring, i, &meta);
 768
 769                 if (!meta->skb || b43_dma_ptr_is_poisoned(meta->skb)) {
 770                         B43_WARN_ON(!ring->tx);
 771                         continue;
 772                 }
 773                 if (ring->tx) {
 774                         unmap_descbuffer(ring, meta->dmaaddr,
 775                                          meta->skb->len, 1);
 776                 } else {
 777                         unmap_descbuffer(ring, meta->dmaaddr,
 778                                          ring->rx_buffersize, 0);
 779                 }
 780                 free_descriptor_buffer(ring, meta);
 781         }
 782 }
 783
 784 static u64 supported_dma_mask(struct b43_wldev *dev)
 785 {
 786         u32 tmp;
 787         u16 mmio_base;
 788
 789         tmp = b43_read32(dev, SSB_TMSHIGH);
 790         if (tmp & SSB_TMSHIGH_DMA64)
 791                 return DMA_BIT_MASK(64);
 792         mmio_base = b43_dmacontroller_base(0, 0);
 793         b43_write32(dev, mmio_base + B43_DMA32_TXCTL, B43_DMA32_TXADDREXT_MASK);
 794         tmp = b43_read32(dev, mmio_base + B43_DMA32_TXCTL);
 795         if (tmp & B43_DMA32_TXADDREXT_MASK)
 796                 return DMA_BIT_MASK(32);
 797
 798         return DMA_BIT_MASK(30);
 799 }
 800
 801 static enum b43_dmatype dma_mask_to_engine_type(u64 dmamask)
 802 {
 803         if (dmamask == DMA_BIT_MASK(30))
 804                 return B43_DMA_30BIT;
 805         if (dmamask == DMA_BIT_MASK(32))
 806                 return B43_DMA_32BIT;
 807         if (dmamask == DMA_BIT_MASK(64))
 808                 return B43_DMA_64BIT;
 809         B43_WARN_ON(1);
 810         return B43_DMA_30BIT;
 811 }
 812
 813 /* Main initialization function. */
 814 static
 815 struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
 816                                       int controller_index,
 817                                       int for_tx,
 818                                       enum b43_dmatype type)
 819 {
 820         struct b43_dmaring *ring;
 821         int i, err;
 822         dma_addr_t dma_test;
 823
 824         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 825         if (!ring)
 826                 goto out;
 827
 828         ring->nr_slots = B43_RXRING_SLOTS;
 829         if (for_tx)
 830                 ring->nr_slots = B43_TXRING_SLOTS;
 831
 832         ring->meta = kcalloc(ring->nr_slots, sizeof(struct b43_dmadesc_meta),
 833                              GFP_KERNEL);
 834         if (!ring->meta)
 835                 goto err_kfree_ring;
 836         for (i = 0; i < ring->nr_slots; i++)
 837                 ring->meta->skb = B43_DMA_PTR_POISON;
 838
 839         ring->type = type;
 840         ring->dev = dev;
 841         ring->mmio_base = b43_dmacontroller_base(type, controller_index);
 842         ring->index = controller_index;
 843         if (type == B43_DMA_64BIT)
 844                 ring->ops = &dma64_ops;
 845         else
 846                 ring->ops = &dma32_ops;
 847         if (for_tx) {
 848                 ring->tx = 1;
 849                 ring->current_slot = -1;
 850         } else {
 851                 if (ring->index == 0) {
 852                         ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
 853                         ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
 854                 } else
 855                         B43_WARN_ON(1);
 856         }
 857 #ifdef CONFIG_B43_DEBUG
 858         ring->last_injected_overflow = jiffies;
 859 #endif
 860
 861         if (for_tx) {
 862                 /* Assumption: B43_TXRING_SLOTS can be divided by TX_SLOTS_PER_FRAME */
 863                 BUILD_BUG_ON(B43_TXRING_SLOTS % TX_SLOTS_PER_FRAME != 0);
 864
 865                 ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 866                                             b43_txhdr_size(dev),
 867                                             GFP_KERNEL);
 868                 if (!ring->txhdr_cache)
 869                         goto err_kfree_meta;
 870
 871                 /* test for ability to dma to txhdr_cache */
 872                 dma_test = dma_map_single(dev->dev->dma_dev,
 873                                           ring->txhdr_cache,
 874                                           b43_txhdr_size(dev),
 875                                           DMA_TO_DEVICE);
 876
 877                 if (b43_dma_mapping_error(ring, dma_test,
 878                                           b43_txhdr_size(dev), 1)) {
 879                         /* ugh realloc */
 880                         kfree(ring->txhdr_cache);
 881                         ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 882                                                     b43_txhdr_size(dev),
 883                                                     GFP_KERNEL | GFP_DMA);
 884                         if (!ring->txhdr_cache)
 885                                 goto err_kfree_meta;
 886
 887                         dma_test = dma_map_single(dev->dev->dma_dev,
 888                                                   ring->txhdr_cache,
 889                                                   b43_txhdr_size(dev),
 890                                                   DMA_TO_DEVICE);
 891
 892                         if (b43_dma_mapping_error(ring, dma_test,
 893                                                   b43_txhdr_size(dev), 1)) {
 894
 895                                 b43err(dev->wl,
 896                                        "TXHDR DMA allocation failed\n");
 897                                 goto err_kfree_txhdr_cache;
 898                         }
 899                 }
 900
 901                 dma_unmap_single(dev->dev->dma_dev,
 902                                  dma_test, b43_txhdr_size(dev),
 903                                  DMA_TO_DEVICE);
 904         }
 905
 906         err = alloc_ringmemory(ring);
 907         if (err)
 908                 goto err_kfree_txhdr_cache;
 909         err = dmacontroller_setup(ring);
 910         if (err)
 911                 goto err_free_ringmemory;
 912
 913       out:
 914         return ring;
 915
 916       err_free_ringmemory:
 917         free_ringmemory(ring);
 918       err_kfree_txhdr_cache:
 919         kfree(ring->txhdr_cache);
 920       err_kfree_meta:
 921         kfree(ring->meta);
 922       err_kfree_ring:
 923         kfree(ring);
 924         ring = NULL;
 925         goto out;
 926 }
 927
 928 #define divide(a, b)    ({      \
 929         typeof(a) __a = a;      \
 930         do_div(__a, b);         \
 931         __a;                    \
 932   })
 933
 934 #define modulo(a, b)    ({      \
 935         typeof(a) __a = a;      \
 936         do_div(__a, b);         \
 937   })
 938
 939 /* Main cleanup function. */
 940 static void b43_destroy_dmaring(struct b43_dmaring *ring,
 941                                 const char *ringname)
 942 {
 943         if (!ring)
 944                 return;
 945
 946 #ifdef CONFIG_B43_DEBUG
 947         {
 948                 /* Print some statistics. */
 949                 u64 failed_packets = ring->nr_failed_tx_packets;
 950                 u64 succeed_packets = ring->nr_succeed_tx_packets;
 951                 u64 nr_packets = failed_packets + succeed_packets;
 952                 u64 permille_failed = 0, average_tries = 0;
 953
 954                 if (nr_packets)
 955                         permille_failed = divide(failed_packets * 1000, nr_packets);
 956                 if (nr_packets)
 957                         average_tries = divide(ring->nr_total_packet_tries * 100, nr_packets);
 958
 959                 b43dbg(ring->dev->wl, "DMA-%u %s: "
 960                        "Used slots %d/%d, Failed frames %llu/%llu = %llu.%01llu%%, "
 961                        "Average tries %llu.%02llu\n",
 962                        (unsigned int)(ring->type), ringname,
 963                        ring->max_used_slots,
 964                        ring->nr_slots,
 965                        (unsigned long long)failed_packets,
 966                        (unsigned long long)nr_packets,
 967                        (unsigned long long)divide(permille_failed, 10),
 968                        (unsigned long long)modulo(permille_failed, 10),
 969                        (unsigned long long)divide(average_tries, 100),
 970                        (unsigned long long)modulo(average_tries, 100));
 971         }
 972 #endif /* DEBUG */
 973
 974         /* Device IRQs are disabled prior entering this function,
 975          * so no need to take care of concurrency with rx handler stuff.
 976          */
 977         dmacontroller_cleanup(ring);
 978         free_all_descbuffers(ring);
 979         free_ringmemory(ring);
 980
 981         kfree(ring->txhdr_cache);
 982         kfree(ring->meta);
 983         kfree(ring);
 984 }
 985
 986 #define destroy_ring(dma, ring) do {                            \
 987         b43_destroy_dmaring((dma)->ring, __stringify(ring));    \
 988         (dma)->ring = NULL;                                     \
 989     } while (0)
 990
 991 void b43_dma_free(struct b43_wldev *dev)
 992 {
 993         struct b43_dma *dma;
 994
 995         if (b43_using_pio_transfers(dev))
 996                 return;
 997         dma = &dev->dma;
 998
 999         destroy_ring(dma, rx_ring);
1000         destroy_ring(dma, tx_ring_AC_BK);
1001         destroy_ring(dma, tx_ring_AC_BE);
1002         destroy_ring(dma, tx_ring_AC_VI);
1003         destroy_ring(dma, tx_ring_AC_VO);
1004         destroy_ring(dma, tx_ring_mcast);
1005 }
1006
1007 static int b43_dma_set_mask(struct b43_wldev *dev, u64 mask)
1008 {
1009         u64 orig_mask = mask;
1010         bool fallback = 0;
1011         int err;
1012
1013         /* Try to set the DMA mask. If it fails, try falling back to a
1014          * lower mask, as we can always also support a lower one. */
1015         while (1) {
1016                 err = dma_set_mask(dev->dev->dma_dev, mask);
1017                 if (!err) {
1018                         err = dma_set_coherent_mask(dev->dev->dma_dev, mask);
1019                         if (!err)
1020                                 break;
1021                 }
1022                 if (mask == DMA_BIT_MASK(64)) {
1023                         mask = DMA_BIT_MASK(32);
1024                         fallback = 1;
1025                         continue;
1026                 }
1027                 if (mask == DMA_BIT_MASK(32)) {
1028                         mask = DMA_BIT_MASK(30);
1029                         fallback = 1;
1030                         continue;
1031                 }
1032                 b43err(dev->wl, "The machine/kernel does not support "
1033                        "the required %u-bit DMA mask\n",
1034                        (unsigned int)dma_mask_to_engine_type(orig_mask));
1035                 return -EOPNOTSUPP;
1036         }
1037         if (fallback) {
1038                 b43info(dev->wl, "DMA mask fallback from %u-bit to %u-bit\n",
1039                         (unsigned int)dma_mask_to_engine_type(orig_mask),
1040                         (unsigned int)dma_mask_to_engine_type(mask));
1041         }
1042
1043         return 0;
1044 }
1045
1046 int b43_dma_init(struct b43_wldev *dev)
1047 {
1048         struct b43_dma *dma = &dev->dma;
1049         int err;
1050         u64 dmamask;
1051         enum b43_dmatype type;
1052
1053         dmamask = supported_dma_mask(dev);
1054         type = dma_mask_to_engine_type(dmamask);
1055         err = b43_dma_set_mask(dev, dmamask);
1056         if (err)
1057                 return err;
1058
1059         err = -ENOMEM;
1060         /* setup TX DMA channels. */
1061         dma->tx_ring_AC_BK = b43_setup_dmaring(dev, 0, 1, type);
1062         if (!dma->tx_ring_AC_BK)
1063                 goto out;
1064
1065         dma->tx_ring_AC_BE = b43_setup_dmaring(dev, 1, 1, type);
1066         if (!dma->tx_ring_AC_BE)
1067                 goto err_destroy_bk;
1068
1069         dma->tx_ring_AC_VI = b43_setup_dmaring(dev, 2, 1, type);
1070         if (!dma->tx_ring_AC_VI)
1071                 goto err_destroy_be;
1072
1073         dma->tx_ring_AC_VO = b43_setup_dmaring(dev, 3, 1, type);
1074         if (!dma->tx_ring_AC_VO)
1075                 goto err_destroy_vi;
1076
1077         dma->tx_ring_mcast = b43_setup_dmaring(dev, 4, 1, type);
1078         if (!dma->tx_ring_mcast)
1079                 goto err_destroy_vo;
1080
1081         /* setup RX DMA channel. */
1082         dma->rx_ring = b43_setup_dmaring(dev, 0, 0, type);
1083         if (!dma->rx_ring)
1084                 goto err_destroy_mcast;
1085
1086         /* No support for the TX status DMA ring. */
1087         B43_WARN_ON(dev->dev->id.revision < 5);
1088
1089         b43dbg(dev->wl, "%u-bit DMA initialized\n",
1090                (unsigned int)type);
1091         err = 0;
1092 out:
1093         return err;
1094
1095 err_destroy_mcast:
1096         destroy_ring(dma, tx_ring_mcast);
1097 err_destroy_vo:
1098         destroy_ring(dma, tx_ring_AC_VO);
1099 err_destroy_vi:
1100         destroy_ring(dma, tx_ring_AC_VI);
1101 err_destroy_be:
1102         destroy_ring(dma, tx_ring_AC_BE);
1103 err_destroy_bk:
1104         destroy_ring(dma, tx_ring_AC_BK);
1105         return err;
1106 }
1107
1108 /* Generate a cookie for the TX header. */
1109 static u16 generate_cookie(struct b43_dmaring *ring, int slot)
1110 {
1111         u16 cookie;
1112
1113         /* Use the upper 4 bits of the cookie as
1114          * DMA controller ID and store the slot number
1115          * in the lower 12 bits.
1116          * Note that the cookie must never be 0, as this
1117          * is a special value used in RX path.
1118          * It can also not be 0xFFFF because that is special
1119          * for multicast frames.
1120          */
1121         cookie = (((u16)ring->index + 1) << 12);
1122         B43_WARN_ON(slot & ~0x0FFF);
1123         cookie |= (u16)slot;
1124
1125         return cookie;
1126 }
1127
1128 /* Inspect a cookie and find out to which controller/slot it belongs. */
1129 static
1130 struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
1131 {
1132         struct b43_dma *dma = &dev->dma;
1133         struct b43_dmaring *ring = NULL;
1134
1135         switch (cookie & 0xF000) {
1136         case 0x1000:
1137                 ring = dma->tx_ring_AC_BK;
1138                 break;
1139         case 0x2000:
1140                 ring = dma->tx_ring_AC_BE;
1141                 break;
1142         case 0x3000:
1143                 ring = dma->tx_ring_AC_VI;
1144                 break;
1145         case 0x4000:
1146                 ring = dma->tx_ring_AC_VO;
1147                 break;
1148         case 0x5000:
1149                 ring = dma->tx_ring_mcast;
1150                 break;
1151         }
1152         *slot = (cookie & 0x0FFF);
1153         if (unlikely(!ring || *slot < 0 || *slot >= ring->nr_slots)) {
1154                 b43dbg(dev->wl, "TX-status contains "
1155                        "invalid cookie: 0x%04X\n", cookie);
1156                 return NULL;
1157         }
1158
1159         return ring;
1160 }
1161
1162 static int dma_tx_fragment(struct b43_dmaring *ring,
1163                            struct sk_buff *skb)
1164 {
1165         const struct b43_dma_ops *ops = ring->ops;
1166         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1167         struct b43_private_tx_info *priv_info = b43_get_priv_tx_info(info);
1168         u8 *header;
1169         int slot, old_top_slot, old_used_slots;
1170         int err;
1171         struct b43_dmadesc_generic *desc;
1172         struct b43_dmadesc_meta *meta;
1173         struct b43_dmadesc_meta *meta_hdr;
1174         u16 cookie;
1175         size_t hdrsize = b43_txhdr_size(ring->dev);
1176
1177         /* Important note: If the number of used DMA slots per TX frame
1178          * is changed here, the TX_SLOTS_PER_FRAME definition at the top of
1179          * the file has to be updated, too!
1180          */
1181
1182         old_top_slot = ring->current_slot;
1183         old_used_slots = ring->used_slots;
1184
1185         /* Get a slot for the header. */
1186         slot = request_slot(ring);
1187         desc = ops->idx2desc(ring, slot, &meta_hdr);
1188         memset(meta_hdr, 0, sizeof(*meta_hdr));
1189
1190         header = &(ring->txhdr_cache[(slot / TX_SLOTS_PER_FRAME) * hdrsize]);
1191         cookie = generate_cookie(ring, slot);
1192         err = b43_generate_txhdr(ring->dev, header,
1193                                  skb, info, cookie);
1194         if (unlikely(err)) {
1195                 ring->current_slot = old_top_slot;
1196                 ring->used_slots = old_used_slots;
1197                 return err;
1198         }
1199
1200         meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1201                                            hdrsize, 1);
1202         if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize, 1)) {
1203                 ring->current_slot = old_top_slot;
1204                 ring->used_slots = old_used_slots;
1205                 return -EIO;
1206         }
1207         ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1208                              hdrsize, 1, 0, 0);
1209
1210         /* Get a slot for the payload. */
1211         slot = request_slot(ring);
1212         desc = ops->idx2desc(ring, slot, &meta);
1213         memset(meta, 0, sizeof(*meta));
1214
1215         meta->skb = skb;
1216         meta->is_last_fragment = 1;
1217         priv_info->bouncebuffer = NULL;
1218
1219         meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1220         /* create a bounce buffer in zone_dma on mapping failure. */
1221         if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1222                 priv_info->bouncebuffer = kmemdup(skb->data, skb->len,
1223                                                   GFP_ATOMIC | GFP_DMA);
1224                 if (!priv_info->bouncebuffer) {
1225                         ring->current_slot = old_top_slot;
1226                         ring->used_slots = old_used_slots;
1227                         err = -ENOMEM;
1228                         goto out_unmap_hdr;
1229                 }
1230
1231                 meta->dmaaddr = map_descbuffer(ring, priv_info->bouncebuffer, skb->len, 1);
1232                 if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1233                         kfree(priv_info->bouncebuffer);
1234                         priv_info->bouncebuffer = NULL;
1235                         ring->current_slot = old_top_slot;
1236                         ring->used_slots = old_used_slots;
1237                         err = -EIO;
1238                         goto out_unmap_hdr;
1239                 }
1240         }
1241
1242         ops->fill_descriptor(ring, desc, meta->dmaaddr, skb->len, 0, 1, 1);
1243
1244         if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1245                 /* Tell the firmware about the cookie of the last
1246                  * mcast frame, so it can clear the more-data bit in it. */
1247                 b43_shm_write16(ring->dev, B43_SHM_SHARED,
1248                                 B43_SHM_SH_MCASTCOOKIE, cookie);
1249         }
1250         /* Now transfer the whole frame. */
1251         wmb();
1252         ops->poke_tx(ring, next_slot(ring, slot));
1253         return 0;
1254
1255 out_unmap_hdr:
1256         unmap_descbuffer(ring, meta_hdr->dmaaddr,
1257                          hdrsize, 1);
1258         return err;
1259 }
1260
1261 static inline int should_inject_overflow(struct b43_dmaring *ring)
1262 {
1263 #ifdef CONFIG_B43_DEBUG
1264         if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
1265                 /* Check if we should inject another ringbuffer overflow
1266                  * to test handling of this situation in the stack. */
1267                 unsigned long next_overflow;
1268
1269                 next_overflow = ring->last_injected_overflow + HZ;
1270                 if (time_after(jiffies, next_overflow)) {
1271                         ring->last_injected_overflow = jiffies;
1272                         b43dbg(ring->dev->wl,
1273                                "Injecting TX ring overflow on "
1274                                "DMA controller %d\n", ring->index);
1275                         return 1;
1276                 }
1277         }
1278 #endif /* CONFIG_B43_DEBUG */
1279         return 0;
1280 }
1281
1282 /* Static mapping of mac80211's queues (priorities) to b43 DMA rings. */
1283 static struct b43_dmaring *select_ring_by_priority(struct b43_wldev *dev,
1284                                                    u8 queue_prio)
1285 {
1286         struct b43_dmaring *ring;
1287
1288         if (dev->qos_enabled) {
1289                 /* 0 = highest priority */
1290                 switch (queue_prio) {
1291                 default:
1292                         B43_WARN_ON(1);
1293                         /* fallthrough */
1294                 case 0:
1295                         ring = dev->dma.tx_ring_AC_VO;
1296                         break;
1297                 case 1:
1298                         ring = dev->dma.tx_ring_AC_VI;
1299                         break;
1300                 case 2:
1301                         ring = dev->dma.tx_ring_AC_BE;
1302                         break;
1303                 case 3:
1304                         ring = dev->dma.tx_ring_AC_BK;
1305                         break;
1306                 }
1307         } else
1308                 ring = dev->dma.tx_ring_AC_BE;
1309
1310         return ring;
1311 }
1312
1313 int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
1314 {
1315         struct b43_dmaring *ring;
1316         struct ieee80211_hdr *hdr;
1317         int err = 0;
1318         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1319
1320         hdr = (struct ieee80211_hdr *)skb->data;
1321         if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1322                 /* The multicast ring will be sent after the DTIM */
1323                 ring = dev->dma.tx_ring_mcast;
1324                 /* Set the more-data bit. Ucode will clear it on
1325                  * the last frame for us. */
1326                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1327         } else {
1328                 /* Decide by priority where to put this frame. */
1329                 ring = select_ring_by_priority(
1330                         dev, skb_get_queue_mapping(skb));
1331         }
1332
1333         B43_WARN_ON(!ring->tx);
1334
1335         if (unlikely(ring->stopped)) {
1336                 /* We get here only because of a bug in mac80211.
1337                  * Because of a race, one packet may be queued after
1338                  * the queue is stopped, thus we got called when we shouldn't.
1339                  * For now, just refuse the transmit. */
1340                 if (b43_debug(dev, B43_DBG_DMAVERBOSE))
1341                         b43err(dev->wl, "Packet after queue stopped\n");
1342                 err = -ENOSPC;
1343                 goto out;
1344         }
1345
1346         if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
1347                 /* If we get here, we have a real error with the queue
1348                  * full, but queues not stopped. */
1349                 b43err(dev->wl, "DMA queue overflow\n");
1350                 err = -ENOSPC;
1351                 goto out;
1352         }
1353
1354         /* Assign the queue number to the ring (if not already done before)
1355          * so TX status handling can use it. The queue to ring mapping is
1356          * static, so we don't need to store it per frame. */
1357         ring->queue_prio = skb_get_queue_mapping(skb);
1358
1359         err = dma_tx_fragment(ring, skb);
1360         if (unlikely(err == -ENOKEY)) {
1361                 /* Drop this packet, as we don't have the encryption key
1362                  * anymore and must not transmit it unencrypted. */
1363                 dev_kfree_skb_any(skb);
1364                 err = 0;
1365                 goto out;
1366         }
1367         if (unlikely(err)) {
1368                 b43err(dev->wl, "DMA tx mapping failure\n");
1369                 goto out;
1370         }
1371         if ((free_slots(ring) < TX_SLOTS_PER_FRAME) ||
1372             should_inject_overflow(ring)) {
1373                 /* This TX ring is full. */
1374                 ieee80211_stop_queue(dev->wl->hw, skb_get_queue_mapping(skb));
1375                 ring->stopped = 1;
1376                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1377                         b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
1378                 }
1379         }
1380 out:
1381
1382         return err;
1383 }
1384
1385 void b43_dma_handle_txstatus(struct b43_wldev *dev,
1386                              const struct b43_txstatus *status)
1387 {
1388         const struct b43_dma_ops *ops;
1389         struct b43_dmaring *ring;
1390         struct b43_dmadesc_generic *desc;
1391         struct b43_dmadesc_meta *meta;
1392         int slot, firstused;
1393         bool frame_succeed;
1394
1395         ring = parse_cookie(dev, status->cookie, &slot);
1396         if (unlikely(!ring))
1397                 return;
1398         B43_WARN_ON(!ring->tx);
1399
1400         /* Sanity check: TX packets are processed in-order on one ring.
1401          * Check if the slot deduced from the cookie really is the first
1402          * used slot. */
1403         firstused = ring->current_slot - ring->used_slots + 1;
1404         if (firstused < 0)
1405                 firstused = ring->nr_slots + firstused;
1406         if (unlikely(slot != firstused)) {
1407                 /* This possibly is a firmware bug and will result in
1408                  * malfunction, memory leaks and/or stall of DMA functionality. */
1409                 b43dbg(dev->wl, "Out of order TX status report on DMA ring %d. "
1410                        "Expected %d, but got %d\n",
1411                        ring->index, firstused, slot);
1412                 return;
1413         }
1414
1415         ops = ring->ops;
1416         while (1) {
1417                 B43_WARN_ON(slot < 0 || slot >= ring->nr_slots);
1418                 desc = ops->idx2desc(ring, slot, &meta);
1419
1420                 if (b43_dma_ptr_is_poisoned(meta->skb)) {
1421                         b43dbg(dev->wl, "Poisoned TX slot %d (first=%d) "
1422                                "on ring %d\n",
1423                                slot, firstused, ring->index);
1424                         break;
1425                 }
1426                 if (meta->skb) {
1427                         struct b43_private_tx_info *priv_info =
1428                                 b43_get_priv_tx_info(IEEE80211_SKB_CB(meta->skb));
1429
1430                         unmap_descbuffer(ring, meta->dmaaddr, meta->skb->len, 1);
1431                         kfree(priv_info->bouncebuffer);
1432                         priv_info->bouncebuffer = NULL;
1433                 } else {
1434                         unmap_descbuffer(ring, meta->dmaaddr,
1435                                          b43_txhdr_size(dev), 1);
1436                 }
1437
1438                 if (meta->is_last_fragment) {
1439                         struct ieee80211_tx_info *info;
1440
1441                         if (unlikely(!meta->skb)) {
1442                                 /* This is a scatter-gather fragment of a frame, so
1443                                  * the skb pointer must not be NULL. */
1444                                 b43dbg(dev->wl, "TX status unexpected NULL skb "
1445                                        "at slot %d (first=%d) on ring %d\n",
1446                                        slot, firstused, ring->index);
1447                                 break;
1448                         }
1449
1450                         info = IEEE80211_SKB_CB(meta->skb);
1451
1452                         /*
1453                          * Call back to inform the ieee80211 subsystem about
1454                          * the status of the transmission.
1455                          */
1456                         frame_succeed = b43_fill_txstatus_report(dev, info, status);
1457 #ifdef CONFIG_B43_DEBUG
1458                         if (frame_succeed)
1459                                 ring->nr_succeed_tx_packets++;
1460                         else
1461                                 ring->nr_failed_tx_packets++;
1462                         ring->nr_total_packet_tries += status->frame_count;
1463 #endif /* DEBUG */
1464                         ieee80211_tx_status(dev->wl->hw, meta->skb);
1465
1466                         /* skb will be freed by ieee80211_tx_status().
1467                          * Poison our pointer. */
1468                         meta->skb = B43_DMA_PTR_POISON;
1469                 } else {
1470                         /* No need to call free_descriptor_buffer here, as
1471                          * this is only the txhdr, which is not allocated.
1472                          */
1473                         if (unlikely(meta->skb)) {
1474                                 b43dbg(dev->wl, "TX status unexpected non-NULL skb "
1475                                        "at slot %d (first=%d) on ring %d\n",
1476                                        slot, firstused, ring->index);
1477                                 break;
1478                         }
1479                 }
1480
1481                 /* Everything unmapped and free'd. So it's not used anymore. */
1482                 ring->used_slots--;
1483
1484                 if (meta->is_last_fragment) {
1485                         /* This is the last scatter-gather
1486                          * fragment of the frame. We are done. */
1487                         break;
1488                 }
1489                 slot = next_slot(ring, slot);
1490         }
1491         if (ring->stopped) {
1492                 B43_WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME);
1493                 ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
1494                 ring->stopped = 0;
1495                 if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1496                         b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
1497                 }
1498         }
1499 }
1500
1501 static void dma_rx(struct b43_dmaring *ring, int *slot)
1502 {
1503         const struct b43_dma_ops *ops = ring->ops;
1504         struct b43_dmadesc_generic *desc;
1505         struct b43_dmadesc_meta *meta;
1506         struct b43_rxhdr_fw4 *rxhdr;
1507         struct sk_buff *skb;
1508         u16 len;
1509         int err;
1510         dma_addr_t dmaaddr;
1511
1512         desc = ops->idx2desc(ring, *slot, &meta);
1513
1514         sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1515         skb = meta->skb;
1516
1517         rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
1518         len = le16_to_cpu(rxhdr->frame_len);
1519         if (len == 0) {
1520                 int i = 0;
1521
1522                 do {
1523                         udelay(2);
1524                         barrier();
1525                         len = le16_to_cpu(rxhdr->frame_len);
1526                 } while (len == 0 && i++ < 5);
1527                 if (unlikely(len == 0)) {
1528                         dmaaddr = meta->dmaaddr;
1529                         goto drop_recycle_buffer;
1530                 }
1531         }
1532         if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
1533                 /* Something went wrong with the DMA.
1534                  * The device did not touch the buffer and did not overwrite the poison. */
1535                 b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
1536                 dmaaddr = meta->dmaaddr;
1537                 goto drop_recycle_buffer;
1538         }
1539         if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
1540                 /* The data did not fit into one descriptor buffer
1541                  * and is split over multiple buffers.
1542                  * This should never happen, as we try to allocate buffers
1543                  * big enough. So simply ignore this packet.
1544                  */
1545                 int cnt = 0;
1546                 s32 tmp = len;
1547
1548                 while (1) {
1549                         desc = ops->idx2desc(ring, *slot, &meta);
1550                         /* recycle the descriptor buffer. */
1551                         b43_poison_rx_buffer(ring, meta->skb);
1552                         sync_descbuffer_for_device(ring, meta->dmaaddr,
1553                                                    ring->rx_buffersize);
1554                         *slot = next_slot(ring, *slot);
1555                         cnt++;
1556                         tmp -= ring->rx_buffersize;
1557                         if (tmp <= 0)
1558                                 break;
1559                 }
1560                 b43err(ring->dev->wl, "DMA RX buffer too small "
1561                        "(len: %u, buffer: %u, nr-dropped: %d)\n",
1562                        len, ring->rx_buffersize, cnt);
1563                 goto drop;
1564         }
1565
1566         dmaaddr = meta->dmaaddr;
1567         err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1568         if (unlikely(err)) {
1569                 b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
1570                 goto drop_recycle_buffer;
1571         }
1572
1573         unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1574         skb_put(skb, len + ring->frameoffset);
1575         skb_pull(skb, ring->frameoffset);
1576
1577         b43_rx(ring->dev, skb, rxhdr);
1578 drop:
1579         return;
1580
1581 drop_recycle_buffer:
1582         /* Poison and recycle the RX buffer. */
1583         b43_poison_rx_buffer(ring, skb);
1584         sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
1585 }
1586
1587 void b43_dma_rx(struct b43_dmaring *ring)
1588 {
1589         const struct b43_dma_ops *ops = ring->ops;
1590         int slot, current_slot;
1591         int used_slots = 0;
1592
1593         B43_WARN_ON(ring->tx);
1594         current_slot = ops->get_current_rxslot(ring);
1595         B43_WARN_ON(!(current_slot >= 0 && current_slot < ring->nr_slots));
1596
1597         slot = ring->current_slot;
1598         for (; slot != current_slot; slot = next_slot(ring, slot)) {
1599                 dma_rx(ring, &slot);
1600                 update_max_used_slots(ring, ++used_slots);
1601         }
1602         ops->set_current_rxslot(ring, slot);
1603         ring->current_slot = slot;
1604 }
1605
1606 static void b43_dma_tx_suspend_ring(struct b43_dmaring *ring)
1607 {
1608         B43_WARN_ON(!ring->tx);
1609         ring->ops->tx_suspend(ring);
1610 }
1611
1612 static void b43_dma_tx_resume_ring(struct b43_dmaring *ring)
1613 {
1614         B43_WARN_ON(!ring->tx);
1615         ring->ops->tx_resume(ring);
1616 }
1617
1618 void b43_dma_tx_suspend(struct b43_wldev *dev)
1619 {
1620         b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
1621         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BK);
1622         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BE);
1623         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VI);
1624         b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VO);
1625         b43_dma_tx_suspend_ring(dev->dma.tx_ring_mcast);
1626 }
1627
1628 void b43_dma_tx_resume(struct b43_wldev *dev)
1629 {
1630         b43_dma_tx_resume_ring(dev->dma.tx_ring_mcast);
1631         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VO);
1632         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VI);
1633         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BE);
1634         b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BK);
1635         b43_power_saving_ctl_bits(dev, 0);
1636 }
1637
1638 static void direct_fifo_rx(struct b43_wldev *dev, enum b43_dmatype type,
1639                            u16 mmio_base, bool enable)
1640 {
1641         u32 ctl;
1642
1643         if (type == B43_DMA_64BIT) {
1644                 ctl = b43_read32(dev, mmio_base + B43_DMA64_RXCTL);
1645                 ctl &= ~B43_DMA64_RXDIRECTFIFO;
1646                 if (enable)
1647                         ctl |= B43_DMA64_RXDIRECTFIFO;
1648                 b43_write32(dev, mmio_base + B43_DMA64_RXCTL, ctl);
1649         } else {
1650                 ctl = b43_read32(dev, mmio_base + B43_DMA32_RXCTL);
1651                 ctl &= ~B43_DMA32_RXDIRECTFIFO;
1652                 if (enable)
1653                         ctl |= B43_DMA32_RXDIRECTFIFO;
1654                 b43_write32(dev, mmio_base + B43_DMA32_RXCTL, ctl);
1655         }
1656 }
1657
1658 /* Enable/Disable Direct FIFO Receive Mode (PIO) on a RX engine.
1659  * This is called from PIO code, so DMA structures are not available. */
1660 void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
1661                             unsigned int engine_index, bool enable)
1662 {
1663         enum b43_dmatype type;
1664         u16 mmio_base;
1665
1666         type = dma_mask_to_engine_type(supported_dma_mask(dev));
1667
1668         mmio_base = b43_dmacontroller_base(type, engine_index);
1669         direct_fifo_rx(dev, type, mmio_base, enable);
1670 }