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v3.1
   1/*
   2
   3  Broadcom B43 wireless driver
   4
   5  DMA ringbuffer and descriptor allocation/management
   6
   7  Copyright (c) 2005, 2006 Michael Buesch <m@bues.ch>
   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. */
  52static
  53struct 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
  66static 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 |= ring->dev->dma.translation;
  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
 100static 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
 106static 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
 112static 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
 118static 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
 128static 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
 134static 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. */
 145static
 146struct 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
 159static 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 |= ring->dev->dma.translation;
 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
 196static 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
 202static 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
 208static 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
 214static 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
 224static 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
 230static 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
 240static inline int free_slots(struct b43_dmaring *ring)
 241{
 242	return (ring->nr_slots - ring->used_slots);
 243}
 244
 245static 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
 253static 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
 262static 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
 276static 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. */
 283static 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
 300static 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
 329static 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
 346static 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
 359static 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
 368static 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
 377static 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
 387static 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
 416static 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 */
 423static 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 */
 462static 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. */
 522static 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
 547address_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
 554static 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
 561static 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
 576static 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 */
 620static 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 */
 656static int dmacontroller_setup(struct b43_dmaring *ring)
 657{
 658	int err = 0;
 659	u32 value;
 660	u32 addrext;
 661	u32 trans = ring->dev->dma.translation;
 662	bool parity = ring->dev->dma.parity;
 
 
 663
 664	if (ring->tx) {
 665		if (ring->type == B43_DMA_64BIT) {
 666			u64 ringbase = (u64) (ring->dmabase);
 
 
 
 667
 668			addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 669			    >> SSB_DMA_TRANSLATION_SHIFT;
 670			value = B43_DMA64_TXENABLE;
 671			value |= (addrext << B43_DMA64_TXADDREXT_SHIFT)
 672			    & B43_DMA64_TXADDREXT_MASK;
 673			if (!parity)
 674				value |= B43_DMA64_TXPARITYDISABLE;
 675			b43_dma_write(ring, B43_DMA64_TXCTL, value);
 676			b43_dma_write(ring, B43_DMA64_TXRINGLO,
 677				      (ringbase & 0xFFFFFFFF));
 678			b43_dma_write(ring, B43_DMA64_TXRINGHI,
 679				      ((ringbase >> 32) &
 680				       ~SSB_DMA_TRANSLATION_MASK)
 681				      | trans);
 682		} else {
 683			u32 ringbase = (u32) (ring->dmabase);
 
 
 684
 685			addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 686			    >> SSB_DMA_TRANSLATION_SHIFT;
 687			value = B43_DMA32_TXENABLE;
 688			value |= (addrext << B43_DMA32_TXADDREXT_SHIFT)
 689			    & B43_DMA32_TXADDREXT_MASK;
 690			if (!parity)
 691				value |= B43_DMA32_TXPARITYDISABLE;
 692			b43_dma_write(ring, B43_DMA32_TXCTL, value);
 693			b43_dma_write(ring, B43_DMA32_TXRING,
 694				      (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 695				      | trans);
 696		}
 697	} else {
 698		err = alloc_initial_descbuffers(ring);
 699		if (err)
 700			goto out;
 701		if (ring->type == B43_DMA_64BIT) {
 702			u64 ringbase = (u64) (ring->dmabase);
 
 
 
 703
 704			addrext = ((ringbase >> 32) & SSB_DMA_TRANSLATION_MASK)
 705			    >> SSB_DMA_TRANSLATION_SHIFT;
 706			value = (ring->frameoffset << B43_DMA64_RXFROFF_SHIFT);
 707			value |= B43_DMA64_RXENABLE;
 708			value |= (addrext << B43_DMA64_RXADDREXT_SHIFT)
 709			    & B43_DMA64_RXADDREXT_MASK;
 710			if (!parity)
 711				value |= B43_DMA64_RXPARITYDISABLE;
 712			b43_dma_write(ring, B43_DMA64_RXCTL, value);
 713			b43_dma_write(ring, B43_DMA64_RXRINGLO,
 714				      (ringbase & 0xFFFFFFFF));
 715			b43_dma_write(ring, B43_DMA64_RXRINGHI,
 716				      ((ringbase >> 32) &
 717				       ~SSB_DMA_TRANSLATION_MASK)
 718				      | trans);
 719			b43_dma_write(ring, B43_DMA64_RXINDEX, ring->nr_slots *
 720				      sizeof(struct b43_dmadesc64));
 721		} else {
 722			u32 ringbase = (u32) (ring->dmabase);
 
 
 723
 724			addrext = (ringbase & SSB_DMA_TRANSLATION_MASK)
 725			    >> SSB_DMA_TRANSLATION_SHIFT;
 726			value = (ring->frameoffset << B43_DMA32_RXFROFF_SHIFT);
 727			value |= B43_DMA32_RXENABLE;
 728			value |= (addrext << B43_DMA32_RXADDREXT_SHIFT)
 729			    & B43_DMA32_RXADDREXT_MASK;
 730			if (!parity)
 731				value |= B43_DMA32_RXPARITYDISABLE;
 732			b43_dma_write(ring, B43_DMA32_RXCTL, value);
 733			b43_dma_write(ring, B43_DMA32_RXRING,
 734				      (ringbase & ~SSB_DMA_TRANSLATION_MASK)
 735				      | trans);
 736			b43_dma_write(ring, B43_DMA32_RXINDEX, ring->nr_slots *
 737				      sizeof(struct b43_dmadesc32));
 738		}
 739	}
 740
 741out:
 742	return err;
 743}
 744
 745/* Shutdown the DMA controller. */
 746static void dmacontroller_cleanup(struct b43_dmaring *ring)
 747{
 748	if (ring->tx) {
 749		b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
 750					   ring->type);
 751		if (ring->type == B43_DMA_64BIT) {
 752			b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
 753			b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
 754		} else
 755			b43_dma_write(ring, B43_DMA32_TXRING, 0);
 756	} else {
 757		b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
 758					   ring->type);
 759		if (ring->type == B43_DMA_64BIT) {
 760			b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
 761			b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
 762		} else
 763			b43_dma_write(ring, B43_DMA32_RXRING, 0);
 764	}
 765}
 766
 767static void free_all_descbuffers(struct b43_dmaring *ring)
 768{
 769	struct b43_dmadesc_meta *meta;
 770	int i;
 771
 772	if (!ring->used_slots)
 773		return;
 774	for (i = 0; i < ring->nr_slots; i++) {
 775		/* get meta - ignore returned value */
 776		ring->ops->idx2desc(ring, i, &meta);
 777
 778		if (!meta->skb || b43_dma_ptr_is_poisoned(meta->skb)) {
 779			B43_WARN_ON(!ring->tx);
 780			continue;
 781		}
 782		if (ring->tx) {
 783			unmap_descbuffer(ring, meta->dmaaddr,
 784					 meta->skb->len, 1);
 785		} else {
 786			unmap_descbuffer(ring, meta->dmaaddr,
 787					 ring->rx_buffersize, 0);
 788		}
 789		free_descriptor_buffer(ring, meta);
 790	}
 791}
 792
 793static u64 supported_dma_mask(struct b43_wldev *dev)
 794{
 795	u32 tmp;
 796	u16 mmio_base;
 797
 798	switch (dev->dev->bus_type) {
 799#ifdef CONFIG_B43_BCMA
 800	case B43_BUS_BCMA:
 801		tmp = bcma_aread32(dev->dev->bdev, BCMA_IOST);
 802		if (tmp & BCMA_IOST_DMA64)
 803			return DMA_BIT_MASK(64);
 804		break;
 805#endif
 806#ifdef CONFIG_B43_SSB
 807	case B43_BUS_SSB:
 808		tmp = ssb_read32(dev->dev->sdev, SSB_TMSHIGH);
 809		if (tmp & SSB_TMSHIGH_DMA64)
 810			return DMA_BIT_MASK(64);
 811		break;
 812#endif
 813	}
 814
 815	mmio_base = b43_dmacontroller_base(0, 0);
 816	b43_write32(dev, mmio_base + B43_DMA32_TXCTL, B43_DMA32_TXADDREXT_MASK);
 817	tmp = b43_read32(dev, mmio_base + B43_DMA32_TXCTL);
 818	if (tmp & B43_DMA32_TXADDREXT_MASK)
 819		return DMA_BIT_MASK(32);
 820
 821	return DMA_BIT_MASK(30);
 822}
 823
 824static enum b43_dmatype dma_mask_to_engine_type(u64 dmamask)
 825{
 826	if (dmamask == DMA_BIT_MASK(30))
 827		return B43_DMA_30BIT;
 828	if (dmamask == DMA_BIT_MASK(32))
 829		return B43_DMA_32BIT;
 830	if (dmamask == DMA_BIT_MASK(64))
 831		return B43_DMA_64BIT;
 832	B43_WARN_ON(1);
 833	return B43_DMA_30BIT;
 834}
 835
 836/* Main initialization function. */
 837static
 838struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
 839				      int controller_index,
 840				      int for_tx,
 841				      enum b43_dmatype type)
 842{
 843	struct b43_dmaring *ring;
 844	int i, err;
 845	dma_addr_t dma_test;
 846
 847	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 848	if (!ring)
 849		goto out;
 850
 851	ring->nr_slots = B43_RXRING_SLOTS;
 852	if (for_tx)
 853		ring->nr_slots = B43_TXRING_SLOTS;
 854
 855	ring->meta = kcalloc(ring->nr_slots, sizeof(struct b43_dmadesc_meta),
 856			     GFP_KERNEL);
 857	if (!ring->meta)
 858		goto err_kfree_ring;
 859	for (i = 0; i < ring->nr_slots; i++)
 860		ring->meta->skb = B43_DMA_PTR_POISON;
 861
 862	ring->type = type;
 863	ring->dev = dev;
 864	ring->mmio_base = b43_dmacontroller_base(type, controller_index);
 865	ring->index = controller_index;
 866	if (type == B43_DMA_64BIT)
 867		ring->ops = &dma64_ops;
 868	else
 869		ring->ops = &dma32_ops;
 870	if (for_tx) {
 871		ring->tx = 1;
 872		ring->current_slot = -1;
 873	} else {
 874		if (ring->index == 0) {
 875			ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
 876			ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
 
 
 
 
 
 
 
 
 
 877		} else
 878			B43_WARN_ON(1);
 879	}
 880#ifdef CONFIG_B43_DEBUG
 881	ring->last_injected_overflow = jiffies;
 882#endif
 883
 884	if (for_tx) {
 885		/* Assumption: B43_TXRING_SLOTS can be divided by TX_SLOTS_PER_FRAME */
 886		BUILD_BUG_ON(B43_TXRING_SLOTS % TX_SLOTS_PER_FRAME != 0);
 887
 888		ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 889					    b43_txhdr_size(dev),
 890					    GFP_KERNEL);
 891		if (!ring->txhdr_cache)
 892			goto err_kfree_meta;
 893
 894		/* test for ability to dma to txhdr_cache */
 895		dma_test = dma_map_single(dev->dev->dma_dev,
 896					  ring->txhdr_cache,
 897					  b43_txhdr_size(dev),
 898					  DMA_TO_DEVICE);
 899
 900		if (b43_dma_mapping_error(ring, dma_test,
 901					  b43_txhdr_size(dev), 1)) {
 902			/* ugh realloc */
 903			kfree(ring->txhdr_cache);
 904			ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 905						    b43_txhdr_size(dev),
 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						  b43_txhdr_size(dev),
 913						  DMA_TO_DEVICE);
 914
 915			if (b43_dma_mapping_error(ring, dma_test,
 916						  b43_txhdr_size(dev), 1)) {
 917
 918				b43err(dev->wl,
 919				       "TXHDR DMA allocation failed\n");
 920				goto err_kfree_txhdr_cache;
 921			}
 922		}
 923
 924		dma_unmap_single(dev->dev->dma_dev,
 925				 dma_test, b43_txhdr_size(dev),
 926				 DMA_TO_DEVICE);
 927	}
 928
 929	err = alloc_ringmemory(ring);
 930	if (err)
 931		goto err_kfree_txhdr_cache;
 932	err = dmacontroller_setup(ring);
 933	if (err)
 934		goto err_free_ringmemory;
 935
 936      out:
 937	return ring;
 938
 939      err_free_ringmemory:
 940	free_ringmemory(ring);
 941      err_kfree_txhdr_cache:
 942	kfree(ring->txhdr_cache);
 943      err_kfree_meta:
 944	kfree(ring->meta);
 945      err_kfree_ring:
 946	kfree(ring);
 947	ring = NULL;
 948	goto out;
 949}
 950
 951#define divide(a, b)	({	\
 952	typeof(a) __a = a;	\
 953	do_div(__a, b);		\
 954	__a;			\
 955  })
 956
 957#define modulo(a, b)	({	\
 958	typeof(a) __a = a;	\
 959	do_div(__a, b);		\
 960  })
 961
 962/* Main cleanup function. */
 963static void b43_destroy_dmaring(struct b43_dmaring *ring,
 964				const char *ringname)
 965{
 966	if (!ring)
 967		return;
 968
 969#ifdef CONFIG_B43_DEBUG
 970	{
 971		/* Print some statistics. */
 972		u64 failed_packets = ring->nr_failed_tx_packets;
 973		u64 succeed_packets = ring->nr_succeed_tx_packets;
 974		u64 nr_packets = failed_packets + succeed_packets;
 975		u64 permille_failed = 0, average_tries = 0;
 976
 977		if (nr_packets)
 978			permille_failed = divide(failed_packets * 1000, nr_packets);
 979		if (nr_packets)
 980			average_tries = divide(ring->nr_total_packet_tries * 100, nr_packets);
 981
 982		b43dbg(ring->dev->wl, "DMA-%u %s: "
 983		       "Used slots %d/%d, Failed frames %llu/%llu = %llu.%01llu%%, "
 984		       "Average tries %llu.%02llu\n",
 985		       (unsigned int)(ring->type), ringname,
 986		       ring->max_used_slots,
 987		       ring->nr_slots,
 988		       (unsigned long long)failed_packets,
 989		       (unsigned long long)nr_packets,
 990		       (unsigned long long)divide(permille_failed, 10),
 991		       (unsigned long long)modulo(permille_failed, 10),
 992		       (unsigned long long)divide(average_tries, 100),
 993		       (unsigned long long)modulo(average_tries, 100));
 994	}
 995#endif /* DEBUG */
 996
 997	/* Device IRQs are disabled prior entering this function,
 998	 * so no need to take care of concurrency with rx handler stuff.
 999	 */
1000	dmacontroller_cleanup(ring);
1001	free_all_descbuffers(ring);
1002	free_ringmemory(ring);
1003
1004	kfree(ring->txhdr_cache);
1005	kfree(ring->meta);
1006	kfree(ring);
1007}
1008
1009#define destroy_ring(dma, ring) do {				\
1010	b43_destroy_dmaring((dma)->ring, __stringify(ring));	\
1011	(dma)->ring = NULL;					\
1012    } while (0)
1013
1014void b43_dma_free(struct b43_wldev *dev)
1015{
1016	struct b43_dma *dma;
1017
1018	if (b43_using_pio_transfers(dev))
1019		return;
1020	dma = &dev->dma;
1021
1022	destroy_ring(dma, rx_ring);
1023	destroy_ring(dma, tx_ring_AC_BK);
1024	destroy_ring(dma, tx_ring_AC_BE);
1025	destroy_ring(dma, tx_ring_AC_VI);
1026	destroy_ring(dma, tx_ring_AC_VO);
1027	destroy_ring(dma, tx_ring_mcast);
1028}
1029
1030static int b43_dma_set_mask(struct b43_wldev *dev, u64 mask)
1031{
1032	u64 orig_mask = mask;
1033	bool fallback = 0;
1034	int err;
1035
1036	/* Try to set the DMA mask. If it fails, try falling back to a
1037	 * lower mask, as we can always also support a lower one. */
1038	while (1) {
1039		err = dma_set_mask(dev->dev->dma_dev, mask);
1040		if (!err) {
1041			err = dma_set_coherent_mask(dev->dev->dma_dev, mask);
1042			if (!err)
1043				break;
1044		}
1045		if (mask == DMA_BIT_MASK(64)) {
1046			mask = DMA_BIT_MASK(32);
1047			fallback = 1;
1048			continue;
1049		}
1050		if (mask == DMA_BIT_MASK(32)) {
1051			mask = DMA_BIT_MASK(30);
1052			fallback = 1;
1053			continue;
1054		}
1055		b43err(dev->wl, "The machine/kernel does not support "
1056		       "the required %u-bit DMA mask\n",
1057		       (unsigned int)dma_mask_to_engine_type(orig_mask));
1058		return -EOPNOTSUPP;
1059	}
1060	if (fallback) {
1061		b43info(dev->wl, "DMA mask fallback from %u-bit to %u-bit\n",
1062			(unsigned int)dma_mask_to_engine_type(orig_mask),
1063			(unsigned int)dma_mask_to_engine_type(mask));
1064	}
1065
1066	return 0;
1067}
1068
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1069int b43_dma_init(struct b43_wldev *dev)
1070{
1071	struct b43_dma *dma = &dev->dma;
1072	int err;
1073	u64 dmamask;
1074	enum b43_dmatype type;
1075
1076	dmamask = supported_dma_mask(dev);
1077	type = dma_mask_to_engine_type(dmamask);
1078	err = b43_dma_set_mask(dev, dmamask);
1079	if (err)
1080		return err;
1081
1082	switch (dev->dev->bus_type) {
1083#ifdef CONFIG_B43_BCMA
1084	case B43_BUS_BCMA:
1085		dma->translation = bcma_core_dma_translation(dev->dev->bdev);
1086		break;
1087#endif
1088#ifdef CONFIG_B43_SSB
1089	case B43_BUS_SSB:
1090		dma->translation = ssb_dma_translation(dev->dev->sdev);
1091		break;
1092#endif
1093	}
 
1094
1095	dma->parity = true;
1096#ifdef CONFIG_B43_BCMA
1097	/* TODO: find out which SSB devices need disabling parity */
1098	if (dev->dev->bus_type == B43_BUS_BCMA)
1099		dma->parity = false;
1100#endif
1101
1102	err = -ENOMEM;
1103	/* setup TX DMA channels. */
1104	dma->tx_ring_AC_BK = b43_setup_dmaring(dev, 0, 1, type);
1105	if (!dma->tx_ring_AC_BK)
1106		goto out;
1107
1108	dma->tx_ring_AC_BE = b43_setup_dmaring(dev, 1, 1, type);
1109	if (!dma->tx_ring_AC_BE)
1110		goto err_destroy_bk;
1111
1112	dma->tx_ring_AC_VI = b43_setup_dmaring(dev, 2, 1, type);
1113	if (!dma->tx_ring_AC_VI)
1114		goto err_destroy_be;
1115
1116	dma->tx_ring_AC_VO = b43_setup_dmaring(dev, 3, 1, type);
1117	if (!dma->tx_ring_AC_VO)
1118		goto err_destroy_vi;
1119
1120	dma->tx_ring_mcast = b43_setup_dmaring(dev, 4, 1, type);
1121	if (!dma->tx_ring_mcast)
1122		goto err_destroy_vo;
1123
1124	/* setup RX DMA channel. */
1125	dma->rx_ring = b43_setup_dmaring(dev, 0, 0, type);
1126	if (!dma->rx_ring)
1127		goto err_destroy_mcast;
1128
1129	/* No support for the TX status DMA ring. */
1130	B43_WARN_ON(dev->dev->core_rev < 5);
1131
1132	b43dbg(dev->wl, "%u-bit DMA initialized\n",
1133	       (unsigned int)type);
1134	err = 0;
1135out:
1136	return err;
1137
1138err_destroy_mcast:
1139	destroy_ring(dma, tx_ring_mcast);
1140err_destroy_vo:
1141	destroy_ring(dma, tx_ring_AC_VO);
1142err_destroy_vi:
1143	destroy_ring(dma, tx_ring_AC_VI);
1144err_destroy_be:
1145	destroy_ring(dma, tx_ring_AC_BE);
1146err_destroy_bk:
1147	destroy_ring(dma, tx_ring_AC_BK);
1148	return err;
1149}
1150
1151/* Generate a cookie for the TX header. */
1152static u16 generate_cookie(struct b43_dmaring *ring, int slot)
1153{
1154	u16 cookie;
1155
1156	/* Use the upper 4 bits of the cookie as
1157	 * DMA controller ID and store the slot number
1158	 * in the lower 12 bits.
1159	 * Note that the cookie must never be 0, as this
1160	 * is a special value used in RX path.
1161	 * It can also not be 0xFFFF because that is special
1162	 * for multicast frames.
1163	 */
1164	cookie = (((u16)ring->index + 1) << 12);
1165	B43_WARN_ON(slot & ~0x0FFF);
1166	cookie |= (u16)slot;
1167
1168	return cookie;
1169}
1170
1171/* Inspect a cookie and find out to which controller/slot it belongs. */
1172static
1173struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
1174{
1175	struct b43_dma *dma = &dev->dma;
1176	struct b43_dmaring *ring = NULL;
1177
1178	switch (cookie & 0xF000) {
1179	case 0x1000:
1180		ring = dma->tx_ring_AC_BK;
1181		break;
1182	case 0x2000:
1183		ring = dma->tx_ring_AC_BE;
1184		break;
1185	case 0x3000:
1186		ring = dma->tx_ring_AC_VI;
1187		break;
1188	case 0x4000:
1189		ring = dma->tx_ring_AC_VO;
1190		break;
1191	case 0x5000:
1192		ring = dma->tx_ring_mcast;
1193		break;
1194	}
1195	*slot = (cookie & 0x0FFF);
1196	if (unlikely(!ring || *slot < 0 || *slot >= ring->nr_slots)) {
1197		b43dbg(dev->wl, "TX-status contains "
1198		       "invalid cookie: 0x%04X\n", cookie);
1199		return NULL;
1200	}
1201
1202	return ring;
1203}
1204
1205static int dma_tx_fragment(struct b43_dmaring *ring,
1206			   struct sk_buff *skb)
1207{
1208	const struct b43_dma_ops *ops = ring->ops;
1209	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1210	struct b43_private_tx_info *priv_info = b43_get_priv_tx_info(info);
1211	u8 *header;
1212	int slot, old_top_slot, old_used_slots;
1213	int err;
1214	struct b43_dmadesc_generic *desc;
1215	struct b43_dmadesc_meta *meta;
1216	struct b43_dmadesc_meta *meta_hdr;
1217	u16 cookie;
1218	size_t hdrsize = b43_txhdr_size(ring->dev);
1219
1220	/* Important note: If the number of used DMA slots per TX frame
1221	 * is changed here, the TX_SLOTS_PER_FRAME definition at the top of
1222	 * the file has to be updated, too!
1223	 */
1224
1225	old_top_slot = ring->current_slot;
1226	old_used_slots = ring->used_slots;
1227
1228	/* Get a slot for the header. */
1229	slot = request_slot(ring);
1230	desc = ops->idx2desc(ring, slot, &meta_hdr);
1231	memset(meta_hdr, 0, sizeof(*meta_hdr));
1232
1233	header = &(ring->txhdr_cache[(slot / TX_SLOTS_PER_FRAME) * hdrsize]);
1234	cookie = generate_cookie(ring, slot);
1235	err = b43_generate_txhdr(ring->dev, header,
1236				 skb, info, cookie);
1237	if (unlikely(err)) {
1238		ring->current_slot = old_top_slot;
1239		ring->used_slots = old_used_slots;
1240		return err;
1241	}
1242
1243	meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1244					   hdrsize, 1);
1245	if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize, 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			     hdrsize, 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	meta->skb = skb;
1259	meta->is_last_fragment = 1;
1260	priv_info->bouncebuffer = NULL;
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 (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1265		priv_info->bouncebuffer = kmemdup(skb->data, skb->len,
1266						  GFP_ATOMIC | GFP_DMA);
1267		if (!priv_info->bouncebuffer) {
1268			ring->current_slot = old_top_slot;
1269			ring->used_slots = old_used_slots;
1270			err = -ENOMEM;
1271			goto out_unmap_hdr;
1272		}
1273
1274		meta->dmaaddr = map_descbuffer(ring, priv_info->bouncebuffer, skb->len, 1);
1275		if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1276			kfree(priv_info->bouncebuffer);
1277			priv_info->bouncebuffer = NULL;
1278			ring->current_slot = old_top_slot;
1279			ring->used_slots = old_used_slots;
1280			err = -EIO;
1281			goto out_unmap_hdr;
1282		}
1283	}
1284
1285	ops->fill_descriptor(ring, desc, meta->dmaaddr, skb->len, 0, 1, 1);
1286
1287	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1288		/* Tell the firmware about the cookie of the last
1289		 * mcast frame, so it can clear the more-data bit in it. */
1290		b43_shm_write16(ring->dev, B43_SHM_SHARED,
1291				B43_SHM_SH_MCASTCOOKIE, cookie);
1292	}
1293	/* Now transfer the whole frame. */
1294	wmb();
1295	ops->poke_tx(ring, next_slot(ring, slot));
1296	return 0;
1297
1298out_unmap_hdr:
1299	unmap_descbuffer(ring, meta_hdr->dmaaddr,
1300			 hdrsize, 1);
1301	return err;
1302}
1303
1304static inline int should_inject_overflow(struct b43_dmaring *ring)
1305{
1306#ifdef CONFIG_B43_DEBUG
1307	if (unlikely(b43_debug(ring->dev, B43_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			b43dbg(ring->dev->wl,
1316			       "Injecting TX ring overflow on "
1317			       "DMA controller %d\n", ring->index);
1318			return 1;
1319		}
1320	}
1321#endif /* CONFIG_B43_DEBUG */
1322	return 0;
1323}
1324
1325/* Static mapping of mac80211's queues (priorities) to b43 DMA rings. */
1326static struct b43_dmaring *select_ring_by_priority(struct b43_wldev *dev,
1327						   u8 queue_prio)
1328{
1329	struct b43_dmaring *ring;
1330
1331	if (dev->qos_enabled) {
1332		/* 0 = highest priority */
1333		switch (queue_prio) {
1334		default:
1335			B43_WARN_ON(1);
1336			/* fallthrough */
1337		case 0:
1338			ring = dev->dma.tx_ring_AC_VO;
1339			break;
1340		case 1:
1341			ring = dev->dma.tx_ring_AC_VI;
1342			break;
1343		case 2:
1344			ring = dev->dma.tx_ring_AC_BE;
1345			break;
1346		case 3:
1347			ring = dev->dma.tx_ring_AC_BK;
1348			break;
1349		}
1350	} else
1351		ring = dev->dma.tx_ring_AC_BE;
1352
1353	return ring;
1354}
1355
1356int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
1357{
1358	struct b43_dmaring *ring;
1359	struct ieee80211_hdr *hdr;
1360	int err = 0;
1361	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1362
1363	hdr = (struct ieee80211_hdr *)skb->data;
1364	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1365		/* The multicast ring will be sent after the DTIM */
1366		ring = dev->dma.tx_ring_mcast;
1367		/* Set the more-data bit. Ucode will clear it on
1368		 * the last frame for us. */
1369		hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1370	} else {
1371		/* Decide by priority where to put this frame. */
1372		ring = select_ring_by_priority(
1373			dev, skb_get_queue_mapping(skb));
1374	}
1375
1376	B43_WARN_ON(!ring->tx);
1377
1378	if (unlikely(ring->stopped)) {
1379		/* We get here only because of a bug in mac80211.
1380		 * Because of a race, one packet may be queued after
1381		 * the queue is stopped, thus we got called when we shouldn't.
1382		 * For now, just refuse the transmit. */
1383		if (b43_debug(dev, B43_DBG_DMAVERBOSE))
1384			b43err(dev->wl, "Packet after queue stopped\n");
1385		err = -ENOSPC;
1386		goto out;
1387	}
1388
1389	if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
1390		/* If we get here, we have a real error with the queue
1391		 * full, but queues not stopped. */
1392		b43err(dev->wl, "DMA queue overflow\n");
1393		err = -ENOSPC;
1394		goto out;
1395	}
1396
1397	/* Assign the queue number to the ring (if not already done before)
1398	 * so TX status handling can use it. The queue to ring mapping is
1399	 * static, so we don't need to store it per frame. */
1400	ring->queue_prio = skb_get_queue_mapping(skb);
1401
1402	err = dma_tx_fragment(ring, skb);
1403	if (unlikely(err == -ENOKEY)) {
1404		/* Drop this packet, as we don't have the encryption key
1405		 * anymore and must not transmit it unencrypted. */
1406		dev_kfree_skb_any(skb);
1407		err = 0;
1408		goto out;
1409	}
1410	if (unlikely(err)) {
1411		b43err(dev->wl, "DMA tx mapping failure\n");
1412		goto out;
1413	}
1414	if ((free_slots(ring) < TX_SLOTS_PER_FRAME) ||
1415	    should_inject_overflow(ring)) {
1416		/* This TX ring is full. */
1417		ieee80211_stop_queue(dev->wl->hw, skb_get_queue_mapping(skb));
1418		ring->stopped = 1;
 
 
1419		if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1420			b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
1421		}
1422	}
1423out:
1424
1425	return err;
1426}
1427
1428void b43_dma_handle_txstatus(struct b43_wldev *dev,
1429			     const struct b43_txstatus *status)
1430{
1431	const struct b43_dma_ops *ops;
1432	struct b43_dmaring *ring;
1433	struct b43_dmadesc_meta *meta;
 
 
1434	int slot, firstused;
1435	bool frame_succeed;
 
 
1436
1437	ring = parse_cookie(dev, status->cookie, &slot);
1438	if (unlikely(!ring))
1439		return;
1440	B43_WARN_ON(!ring->tx);
1441
1442	/* Sanity check: TX packets are processed in-order on one ring.
1443	 * Check if the slot deduced from the cookie really is the first
1444	 * used slot. */
1445	firstused = ring->current_slot - ring->used_slots + 1;
1446	if (firstused < 0)
1447		firstused = ring->nr_slots + firstused;
 
 
1448	if (unlikely(slot != firstused)) {
1449		/* This possibly is a firmware bug and will result in
1450		 * malfunction, memory leaks and/or stall of DMA functionality. */
1451		b43dbg(dev->wl, "Out of order TX status report on DMA ring %d. "
1452		       "Expected %d, but got %d\n",
1453		       ring->index, firstused, slot);
1454		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1455	}
1456
1457	ops = ring->ops;
1458	while (1) {
1459		B43_WARN_ON(slot < 0 || slot >= ring->nr_slots);
1460		/* get meta - ignore returned value */
1461		ops->idx2desc(ring, slot, &meta);
1462
1463		if (b43_dma_ptr_is_poisoned(meta->skb)) {
1464			b43dbg(dev->wl, "Poisoned TX slot %d (first=%d) "
1465			       "on ring %d\n",
1466			       slot, firstused, ring->index);
1467			break;
1468		}
 
1469		if (meta->skb) {
1470			struct b43_private_tx_info *priv_info =
1471				b43_get_priv_tx_info(IEEE80211_SKB_CB(meta->skb));
1472
1473			unmap_descbuffer(ring, meta->dmaaddr, meta->skb->len, 1);
 
1474			kfree(priv_info->bouncebuffer);
1475			priv_info->bouncebuffer = NULL;
1476		} else {
1477			unmap_descbuffer(ring, meta->dmaaddr,
1478					 b43_txhdr_size(dev), 1);
1479		}
1480
1481		if (meta->is_last_fragment) {
1482			struct ieee80211_tx_info *info;
1483
1484			if (unlikely(!meta->skb)) {
1485				/* This is a scatter-gather fragment of a frame, so
1486				 * the skb pointer must not be NULL. */
 
1487				b43dbg(dev->wl, "TX status unexpected NULL skb "
1488				       "at slot %d (first=%d) on ring %d\n",
1489				       slot, firstused, ring->index);
1490				break;
1491			}
1492
1493			info = IEEE80211_SKB_CB(meta->skb);
1494
1495			/*
1496			 * Call back to inform the ieee80211 subsystem about
1497			 * the status of the transmission.
 
 
 
1498			 */
1499			frame_succeed = b43_fill_txstatus_report(dev, info, status);
 
 
 
 
 
 
1500#ifdef CONFIG_B43_DEBUG
1501			if (frame_succeed)
1502				ring->nr_succeed_tx_packets++;
1503			else
1504				ring->nr_failed_tx_packets++;
1505			ring->nr_total_packet_tries += status->frame_count;
1506#endif /* DEBUG */
1507			ieee80211_tx_status(dev->wl->hw, meta->skb);
1508
1509			/* skb will be freed by ieee80211_tx_status().
1510			 * Poison our pointer. */
1511			meta->skb = B43_DMA_PTR_POISON;
1512		} else {
1513			/* No need to call free_descriptor_buffer here, as
1514			 * this is only the txhdr, which is not allocated.
1515			 */
1516			if (unlikely(meta->skb)) {
1517				b43dbg(dev->wl, "TX status unexpected non-NULL skb "
1518				       "at slot %d (first=%d) on ring %d\n",
1519				       slot, firstused, ring->index);
1520				break;
1521			}
1522		}
1523
1524		/* Everything unmapped and free'd. So it's not used anymore. */
1525		ring->used_slots--;
1526
1527		if (meta->is_last_fragment) {
1528			/* This is the last scatter-gather
1529			 * fragment of the frame. We are done. */
1530			break;
1531		}
1532		slot = next_slot(ring, slot);
 
 
1533	}
1534	if (ring->stopped) {
1535		B43_WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME);
 
 
 
 
 
 
 
 
1536		ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
1537		ring->stopped = 0;
1538		if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1539			b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
1540		}
1541	}
 
 
1542}
1543
1544static void dma_rx(struct b43_dmaring *ring, int *slot)
1545{
1546	const struct b43_dma_ops *ops = ring->ops;
1547	struct b43_dmadesc_generic *desc;
1548	struct b43_dmadesc_meta *meta;
1549	struct b43_rxhdr_fw4 *rxhdr;
1550	struct sk_buff *skb;
1551	u16 len;
1552	int err;
1553	dma_addr_t dmaaddr;
1554
1555	desc = ops->idx2desc(ring, *slot, &meta);
1556
1557	sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1558	skb = meta->skb;
1559
1560	rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
1561	len = le16_to_cpu(rxhdr->frame_len);
1562	if (len == 0) {
1563		int i = 0;
1564
1565		do {
1566			udelay(2);
1567			barrier();
1568			len = le16_to_cpu(rxhdr->frame_len);
1569		} while (len == 0 && i++ < 5);
1570		if (unlikely(len == 0)) {
1571			dmaaddr = meta->dmaaddr;
1572			goto drop_recycle_buffer;
1573		}
1574	}
1575	if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
1576		/* Something went wrong with the DMA.
1577		 * The device did not touch the buffer and did not overwrite the poison. */
1578		b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
1579		dmaaddr = meta->dmaaddr;
1580		goto drop_recycle_buffer;
1581	}
1582	if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
1583		/* The data did not fit into one descriptor buffer
1584		 * and is split over multiple buffers.
1585		 * This should never happen, as we try to allocate buffers
1586		 * big enough. So simply ignore this packet.
1587		 */
1588		int cnt = 0;
1589		s32 tmp = len;
1590
1591		while (1) {
1592			desc = ops->idx2desc(ring, *slot, &meta);
1593			/* recycle the descriptor buffer. */
1594			b43_poison_rx_buffer(ring, meta->skb);
1595			sync_descbuffer_for_device(ring, meta->dmaaddr,
1596						   ring->rx_buffersize);
1597			*slot = next_slot(ring, *slot);
1598			cnt++;
1599			tmp -= ring->rx_buffersize;
1600			if (tmp <= 0)
1601				break;
1602		}
1603		b43err(ring->dev->wl, "DMA RX buffer too small "
1604		       "(len: %u, buffer: %u, nr-dropped: %d)\n",
1605		       len, ring->rx_buffersize, cnt);
1606		goto drop;
1607	}
1608
1609	dmaaddr = meta->dmaaddr;
1610	err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1611	if (unlikely(err)) {
1612		b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
1613		goto drop_recycle_buffer;
1614	}
1615
1616	unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1617	skb_put(skb, len + ring->frameoffset);
1618	skb_pull(skb, ring->frameoffset);
1619
1620	b43_rx(ring->dev, skb, rxhdr);
1621drop:
1622	return;
1623
1624drop_recycle_buffer:
1625	/* Poison and recycle the RX buffer. */
1626	b43_poison_rx_buffer(ring, skb);
1627	sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1628}
1629
1630void b43_dma_rx(struct b43_dmaring *ring)
1631{
1632	const struct b43_dma_ops *ops = ring->ops;
1633	int slot, current_slot;
1634	int used_slots = 0;
1635
1636	B43_WARN_ON(ring->tx);
1637	current_slot = ops->get_current_rxslot(ring);
1638	B43_WARN_ON(!(current_slot >= 0 && current_slot < ring->nr_slots));
1639
1640	slot = ring->current_slot;
1641	for (; slot != current_slot; slot = next_slot(ring, slot)) {
1642		dma_rx(ring, &slot);
1643		update_max_used_slots(ring, ++used_slots);
1644	}
1645	wmb();
1646	ops->set_current_rxslot(ring, slot);
1647	ring->current_slot = slot;
1648}
1649
1650static void b43_dma_tx_suspend_ring(struct b43_dmaring *ring)
1651{
1652	B43_WARN_ON(!ring->tx);
1653	ring->ops->tx_suspend(ring);
1654}
1655
1656static void b43_dma_tx_resume_ring(struct b43_dmaring *ring)
1657{
1658	B43_WARN_ON(!ring->tx);
1659	ring->ops->tx_resume(ring);
1660}
1661
1662void b43_dma_tx_suspend(struct b43_wldev *dev)
1663{
1664	b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
1665	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BK);
1666	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BE);
1667	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VI);
1668	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VO);
1669	b43_dma_tx_suspend_ring(dev->dma.tx_ring_mcast);
1670}
1671
1672void b43_dma_tx_resume(struct b43_wldev *dev)
1673{
1674	b43_dma_tx_resume_ring(dev->dma.tx_ring_mcast);
1675	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VO);
1676	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VI);
1677	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BE);
1678	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BK);
1679	b43_power_saving_ctl_bits(dev, 0);
1680}
1681
1682static void direct_fifo_rx(struct b43_wldev *dev, enum b43_dmatype type,
1683			   u16 mmio_base, bool enable)
1684{
1685	u32 ctl;
1686
1687	if (type == B43_DMA_64BIT) {
1688		ctl = b43_read32(dev, mmio_base + B43_DMA64_RXCTL);
1689		ctl &= ~B43_DMA64_RXDIRECTFIFO;
1690		if (enable)
1691			ctl |= B43_DMA64_RXDIRECTFIFO;
1692		b43_write32(dev, mmio_base + B43_DMA64_RXCTL, ctl);
1693	} else {
1694		ctl = b43_read32(dev, mmio_base + B43_DMA32_RXCTL);
1695		ctl &= ~B43_DMA32_RXDIRECTFIFO;
1696		if (enable)
1697			ctl |= B43_DMA32_RXDIRECTFIFO;
1698		b43_write32(dev, mmio_base + B43_DMA32_RXCTL, ctl);
1699	}
1700}
1701
1702/* Enable/Disable Direct FIFO Receive Mode (PIO) on a RX engine.
1703 * This is called from PIO code, so DMA structures are not available. */
1704void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
1705			    unsigned int engine_index, bool enable)
1706{
1707	enum b43_dmatype type;
1708	u16 mmio_base;
1709
1710	type = dma_mask_to_engine_type(supported_dma_mask(dev));
1711
1712	mmio_base = b43_dmacontroller_base(type, engine_index);
1713	direct_fifo_rx(dev, type, mmio_base, enable);
1714}
v3.15
   1/*
   2
   3  Broadcom B43 wireless driver
   4
   5  DMA ringbuffer and descriptor allocation/management
   6
   7  Copyright (c) 2005, 2006 Michael Buesch <m@bues.ch>
   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
  50static u32 b43_dma_address(struct b43_dma *dma, dma_addr_t dmaaddr,
  51			   enum b43_addrtype addrtype)
  52{
  53	u32 uninitialized_var(addr);
  54
  55	switch (addrtype) {
  56	case B43_DMA_ADDR_LOW:
  57		addr = lower_32_bits(dmaaddr);
  58		if (dma->translation_in_low) {
  59			addr &= ~SSB_DMA_TRANSLATION_MASK;
  60			addr |= dma->translation;
  61		}
  62		break;
  63	case B43_DMA_ADDR_HIGH:
  64		addr = upper_32_bits(dmaaddr);
  65		if (!dma->translation_in_low) {
  66			addr &= ~SSB_DMA_TRANSLATION_MASK;
  67			addr |= dma->translation;
  68		}
  69		break;
  70	case B43_DMA_ADDR_EXT:
  71		if (dma->translation_in_low)
  72			addr = lower_32_bits(dmaaddr);
  73		else
  74			addr = upper_32_bits(dmaaddr);
  75		addr &= SSB_DMA_TRANSLATION_MASK;
  76		addr >>= SSB_DMA_TRANSLATION_SHIFT;
  77		break;
  78	}
  79
  80	return addr;
  81}
  82
  83/* 32bit DMA ops. */
  84static
  85struct b43_dmadesc_generic *op32_idx2desc(struct b43_dmaring *ring,
  86					  int slot,
  87					  struct b43_dmadesc_meta **meta)
  88{
  89	struct b43_dmadesc32 *desc;
  90
  91	*meta = &(ring->meta[slot]);
  92	desc = ring->descbase;
  93	desc = &(desc[slot]);
  94
  95	return (struct b43_dmadesc_generic *)desc;
  96}
  97
  98static void op32_fill_descriptor(struct b43_dmaring *ring,
  99				 struct b43_dmadesc_generic *desc,
 100				 dma_addr_t dmaaddr, u16 bufsize,
 101				 int start, int end, int irq)
 102{
 103	struct b43_dmadesc32 *descbase = ring->descbase;
 104	int slot;
 105	u32 ctl;
 106	u32 addr;
 107	u32 addrext;
 108
 109	slot = (int)(&(desc->dma32) - descbase);
 110	B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
 111
 112	addr = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_LOW);
 113	addrext = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_EXT);
 114
 
 115	ctl = bufsize & B43_DMA32_DCTL_BYTECNT;
 116	if (slot == ring->nr_slots - 1)
 117		ctl |= B43_DMA32_DCTL_DTABLEEND;
 118	if (start)
 119		ctl |= B43_DMA32_DCTL_FRAMESTART;
 120	if (end)
 121		ctl |= B43_DMA32_DCTL_FRAMEEND;
 122	if (irq)
 123		ctl |= B43_DMA32_DCTL_IRQ;
 124	ctl |= (addrext << B43_DMA32_DCTL_ADDREXT_SHIFT)
 125	    & B43_DMA32_DCTL_ADDREXT_MASK;
 126
 127	desc->dma32.control = cpu_to_le32(ctl);
 128	desc->dma32.address = cpu_to_le32(addr);
 129}
 130
 131static void op32_poke_tx(struct b43_dmaring *ring, int slot)
 132{
 133	b43_dma_write(ring, B43_DMA32_TXINDEX,
 134		      (u32) (slot * sizeof(struct b43_dmadesc32)));
 135}
 136
 137static void op32_tx_suspend(struct b43_dmaring *ring)
 138{
 139	b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 140		      | B43_DMA32_TXSUSPEND);
 141}
 142
 143static void op32_tx_resume(struct b43_dmaring *ring)
 144{
 145	b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
 146		      & ~B43_DMA32_TXSUSPEND);
 147}
 148
 149static int op32_get_current_rxslot(struct b43_dmaring *ring)
 150{
 151	u32 val;
 152
 153	val = b43_dma_read(ring, B43_DMA32_RXSTATUS);
 154	val &= B43_DMA32_RXDPTR;
 155
 156	return (val / sizeof(struct b43_dmadesc32));
 157}
 158
 159static void op32_set_current_rxslot(struct b43_dmaring *ring, int slot)
 160{
 161	b43_dma_write(ring, B43_DMA32_RXINDEX,
 162		      (u32) (slot * sizeof(struct b43_dmadesc32)));
 163}
 164
 165static const struct b43_dma_ops dma32_ops = {
 166	.idx2desc = op32_idx2desc,
 167	.fill_descriptor = op32_fill_descriptor,
 168	.poke_tx = op32_poke_tx,
 169	.tx_suspend = op32_tx_suspend,
 170	.tx_resume = op32_tx_resume,
 171	.get_current_rxslot = op32_get_current_rxslot,
 172	.set_current_rxslot = op32_set_current_rxslot,
 173};
 174
 175/* 64bit DMA ops. */
 176static
 177struct b43_dmadesc_generic *op64_idx2desc(struct b43_dmaring *ring,
 178					  int slot,
 179					  struct b43_dmadesc_meta **meta)
 180{
 181	struct b43_dmadesc64 *desc;
 182
 183	*meta = &(ring->meta[slot]);
 184	desc = ring->descbase;
 185	desc = &(desc[slot]);
 186
 187	return (struct b43_dmadesc_generic *)desc;
 188}
 189
 190static void op64_fill_descriptor(struct b43_dmaring *ring,
 191				 struct b43_dmadesc_generic *desc,
 192				 dma_addr_t dmaaddr, u16 bufsize,
 193				 int start, int end, int irq)
 194{
 195	struct b43_dmadesc64 *descbase = ring->descbase;
 196	int slot;
 197	u32 ctl0 = 0, ctl1 = 0;
 198	u32 addrlo, addrhi;
 199	u32 addrext;
 200
 201	slot = (int)(&(desc->dma64) - descbase);
 202	B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));
 203
 204	addrlo = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_LOW);
 205	addrhi = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_HIGH);
 206	addrext = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_EXT);
 207
 
 208	if (slot == ring->nr_slots - 1)
 209		ctl0 |= B43_DMA64_DCTL0_DTABLEEND;
 210	if (start)
 211		ctl0 |= B43_DMA64_DCTL0_FRAMESTART;
 212	if (end)
 213		ctl0 |= B43_DMA64_DCTL0_FRAMEEND;
 214	if (irq)
 215		ctl0 |= B43_DMA64_DCTL0_IRQ;
 216	ctl1 |= bufsize & B43_DMA64_DCTL1_BYTECNT;
 217	ctl1 |= (addrext << B43_DMA64_DCTL1_ADDREXT_SHIFT)
 218	    & B43_DMA64_DCTL1_ADDREXT_MASK;
 219
 220	desc->dma64.control0 = cpu_to_le32(ctl0);
 221	desc->dma64.control1 = cpu_to_le32(ctl1);
 222	desc->dma64.address_low = cpu_to_le32(addrlo);
 223	desc->dma64.address_high = cpu_to_le32(addrhi);
 224}
 225
 226static void op64_poke_tx(struct b43_dmaring *ring, int slot)
 227{
 228	b43_dma_write(ring, B43_DMA64_TXINDEX,
 229		      (u32) (slot * sizeof(struct b43_dmadesc64)));
 230}
 231
 232static void op64_tx_suspend(struct b43_dmaring *ring)
 233{
 234	b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
 235		      | B43_DMA64_TXSUSPEND);
 236}
 237
 238static void op64_tx_resume(struct b43_dmaring *ring)
 239{
 240	b43_dma_write(ring, B43_DMA64_TXCTL, b43_dma_read(ring, B43_DMA64_TXCTL)
 241		      & ~B43_DMA64_TXSUSPEND);
 242}
 243
 244static int op64_get_current_rxslot(struct b43_dmaring *ring)
 245{
 246	u32 val;
 247
 248	val = b43_dma_read(ring, B43_DMA64_RXSTATUS);
 249	val &= B43_DMA64_RXSTATDPTR;
 250
 251	return (val / sizeof(struct b43_dmadesc64));
 252}
 253
 254static void op64_set_current_rxslot(struct b43_dmaring *ring, int slot)
 255{
 256	b43_dma_write(ring, B43_DMA64_RXINDEX,
 257		      (u32) (slot * sizeof(struct b43_dmadesc64)));
 258}
 259
 260static const struct b43_dma_ops dma64_ops = {
 261	.idx2desc = op64_idx2desc,
 262	.fill_descriptor = op64_fill_descriptor,
 263	.poke_tx = op64_poke_tx,
 264	.tx_suspend = op64_tx_suspend,
 265	.tx_resume = op64_tx_resume,
 266	.get_current_rxslot = op64_get_current_rxslot,
 267	.set_current_rxslot = op64_set_current_rxslot,
 268};
 269
 270static inline int free_slots(struct b43_dmaring *ring)
 271{
 272	return (ring->nr_slots - ring->used_slots);
 273}
 274
 275static inline int next_slot(struct b43_dmaring *ring, int slot)
 276{
 277	B43_WARN_ON(!(slot >= -1 && slot <= ring->nr_slots - 1));
 278	if (slot == ring->nr_slots - 1)
 279		return 0;
 280	return slot + 1;
 281}
 282
 283static inline int prev_slot(struct b43_dmaring *ring, int slot)
 284{
 285	B43_WARN_ON(!(slot >= 0 && slot <= ring->nr_slots - 1));
 286	if (slot == 0)
 287		return ring->nr_slots - 1;
 288	return slot - 1;
 289}
 290
 291#ifdef CONFIG_B43_DEBUG
 292static void update_max_used_slots(struct b43_dmaring *ring,
 293				  int current_used_slots)
 294{
 295	if (current_used_slots <= ring->max_used_slots)
 296		return;
 297	ring->max_used_slots = current_used_slots;
 298	if (b43_debug(ring->dev, B43_DBG_DMAVERBOSE)) {
 299		b43dbg(ring->dev->wl,
 300		       "max_used_slots increased to %d on %s ring %d\n",
 301		       ring->max_used_slots,
 302		       ring->tx ? "TX" : "RX", ring->index);
 303	}
 304}
 305#else
 306static inline
 307    void update_max_used_slots(struct b43_dmaring *ring, int current_used_slots)
 308{
 309}
 310#endif /* DEBUG */
 311
 312/* Request a slot for usage. */
 313static inline int request_slot(struct b43_dmaring *ring)
 314{
 315	int slot;
 316
 317	B43_WARN_ON(!ring->tx);
 318	B43_WARN_ON(ring->stopped);
 319	B43_WARN_ON(free_slots(ring) == 0);
 320
 321	slot = next_slot(ring, ring->current_slot);
 322	ring->current_slot = slot;
 323	ring->used_slots++;
 324
 325	update_max_used_slots(ring, ring->used_slots);
 326
 327	return slot;
 328}
 329
 330static u16 b43_dmacontroller_base(enum b43_dmatype type, int controller_idx)
 331{
 332	static const u16 map64[] = {
 333		B43_MMIO_DMA64_BASE0,
 334		B43_MMIO_DMA64_BASE1,
 335		B43_MMIO_DMA64_BASE2,
 336		B43_MMIO_DMA64_BASE3,
 337		B43_MMIO_DMA64_BASE4,
 338		B43_MMIO_DMA64_BASE5,
 339	};
 340	static const u16 map32[] = {
 341		B43_MMIO_DMA32_BASE0,
 342		B43_MMIO_DMA32_BASE1,
 343		B43_MMIO_DMA32_BASE2,
 344		B43_MMIO_DMA32_BASE3,
 345		B43_MMIO_DMA32_BASE4,
 346		B43_MMIO_DMA32_BASE5,
 347	};
 348
 349	if (type == B43_DMA_64BIT) {
 350		B43_WARN_ON(!(controller_idx >= 0 &&
 351			      controller_idx < ARRAY_SIZE(map64)));
 352		return map64[controller_idx];
 353	}
 354	B43_WARN_ON(!(controller_idx >= 0 &&
 355		      controller_idx < ARRAY_SIZE(map32)));
 356	return map32[controller_idx];
 357}
 358
 359static inline
 360    dma_addr_t map_descbuffer(struct b43_dmaring *ring,
 361			      unsigned char *buf, size_t len, int tx)
 362{
 363	dma_addr_t dmaaddr;
 364
 365	if (tx) {
 366		dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 367					 buf, len, DMA_TO_DEVICE);
 368	} else {
 369		dmaaddr = dma_map_single(ring->dev->dev->dma_dev,
 370					 buf, len, DMA_FROM_DEVICE);
 371	}
 372
 373	return dmaaddr;
 374}
 375
 376static inline
 377    void unmap_descbuffer(struct b43_dmaring *ring,
 378			  dma_addr_t addr, size_t len, int tx)
 379{
 380	if (tx) {
 381		dma_unmap_single(ring->dev->dev->dma_dev,
 382				 addr, len, DMA_TO_DEVICE);
 383	} else {
 384		dma_unmap_single(ring->dev->dev->dma_dev,
 385				 addr, len, DMA_FROM_DEVICE);
 386	}
 387}
 388
 389static inline
 390    void sync_descbuffer_for_cpu(struct b43_dmaring *ring,
 391				 dma_addr_t addr, size_t len)
 392{
 393	B43_WARN_ON(ring->tx);
 394	dma_sync_single_for_cpu(ring->dev->dev->dma_dev,
 395				    addr, len, DMA_FROM_DEVICE);
 396}
 397
 398static inline
 399    void sync_descbuffer_for_device(struct b43_dmaring *ring,
 400				    dma_addr_t addr, size_t len)
 401{
 402	B43_WARN_ON(ring->tx);
 403	dma_sync_single_for_device(ring->dev->dev->dma_dev,
 404				   addr, len, DMA_FROM_DEVICE);
 405}
 406
 407static inline
 408    void free_descriptor_buffer(struct b43_dmaring *ring,
 409				struct b43_dmadesc_meta *meta)
 410{
 411	if (meta->skb) {
 412		if (ring->tx)
 413			ieee80211_free_txskb(ring->dev->wl->hw, meta->skb);
 414		else
 415			dev_kfree_skb_any(meta->skb);
 416		meta->skb = NULL;
 417	}
 418}
 419
 420static int alloc_ringmemory(struct b43_dmaring *ring)
 421{
 
 
 422	/* The specs call for 4K buffers for 30- and 32-bit DMA with 4K
 423	 * alignment and 8K buffers for 64-bit DMA with 8K alignment.
 424	 * In practice we could use smaller buffers for the latter, but the
 425	 * alignment is really important because of the hardware bug. If bit
 426	 * 0x00001000 is used in DMA address, some hardware (like BCM4331)
 427	 * copies that bit into B43_DMA64_RXSTATUS and we get false values from
 428	 * B43_DMA64_RXSTATDPTR. Let's just use 8K buffers even if we don't use
 429	 * more than 256 slots for ring.
 
 
 430	 */
 431	u16 ring_mem_size = (ring->type == B43_DMA_64BIT) ?
 432				B43_DMA64_RINGMEMSIZE : B43_DMA32_RINGMEMSIZE;
 433
 434	ring->descbase = dma_zalloc_coherent(ring->dev->dev->dma_dev,
 435					     ring_mem_size, &(ring->dmabase),
 436					     GFP_KERNEL);
 437	if (!ring->descbase)
 438		return -ENOMEM;
 
 
 439
 440	return 0;
 441}
 442
 443static void free_ringmemory(struct b43_dmaring *ring)
 444{
 445	u16 ring_mem_size = (ring->type == B43_DMA_64BIT) ?
 446				B43_DMA64_RINGMEMSIZE : B43_DMA32_RINGMEMSIZE;
 447	dma_free_coherent(ring->dev->dev->dma_dev, ring_mem_size,
 448			  ring->descbase, ring->dmabase);
 449}
 450
 451/* Reset the RX DMA channel */
 452static int b43_dmacontroller_rx_reset(struct b43_wldev *dev, u16 mmio_base,
 453				      enum b43_dmatype type)
 454{
 455	int i;
 456	u32 value;
 457	u16 offset;
 458
 459	might_sleep();
 460
 461	offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXCTL : B43_DMA32_RXCTL;
 462	b43_write32(dev, mmio_base + offset, 0);
 463	for (i = 0; i < 10; i++) {
 464		offset = (type == B43_DMA_64BIT) ? B43_DMA64_RXSTATUS :
 465						   B43_DMA32_RXSTATUS;
 466		value = b43_read32(dev, mmio_base + offset);
 467		if (type == B43_DMA_64BIT) {
 468			value &= B43_DMA64_RXSTAT;
 469			if (value == B43_DMA64_RXSTAT_DISABLED) {
 470				i = -1;
 471				break;
 472			}
 473		} else {
 474			value &= B43_DMA32_RXSTATE;
 475			if (value == B43_DMA32_RXSTAT_DISABLED) {
 476				i = -1;
 477				break;
 478			}
 479		}
 480		msleep(1);
 481	}
 482	if (i != -1) {
 483		b43err(dev->wl, "DMA RX reset timed out\n");
 484		return -ENODEV;
 485	}
 486
 487	return 0;
 488}
 489
 490/* Reset the TX DMA channel */
 491static int b43_dmacontroller_tx_reset(struct b43_wldev *dev, u16 mmio_base,
 492				      enum b43_dmatype type)
 493{
 494	int i;
 495	u32 value;
 496	u16 offset;
 497
 498	might_sleep();
 499
 500	for (i = 0; i < 10; i++) {
 501		offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 502						   B43_DMA32_TXSTATUS;
 503		value = b43_read32(dev, mmio_base + offset);
 504		if (type == B43_DMA_64BIT) {
 505			value &= B43_DMA64_TXSTAT;
 506			if (value == B43_DMA64_TXSTAT_DISABLED ||
 507			    value == B43_DMA64_TXSTAT_IDLEWAIT ||
 508			    value == B43_DMA64_TXSTAT_STOPPED)
 509				break;
 510		} else {
 511			value &= B43_DMA32_TXSTATE;
 512			if (value == B43_DMA32_TXSTAT_DISABLED ||
 513			    value == B43_DMA32_TXSTAT_IDLEWAIT ||
 514			    value == B43_DMA32_TXSTAT_STOPPED)
 515				break;
 516		}
 517		msleep(1);
 518	}
 519	offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXCTL : B43_DMA32_TXCTL;
 520	b43_write32(dev, mmio_base + offset, 0);
 521	for (i = 0; i < 10; i++) {
 522		offset = (type == B43_DMA_64BIT) ? B43_DMA64_TXSTATUS :
 523						   B43_DMA32_TXSTATUS;
 524		value = b43_read32(dev, mmio_base + offset);
 525		if (type == B43_DMA_64BIT) {
 526			value &= B43_DMA64_TXSTAT;
 527			if (value == B43_DMA64_TXSTAT_DISABLED) {
 528				i = -1;
 529				break;
 530			}
 531		} else {
 532			value &= B43_DMA32_TXSTATE;
 533			if (value == B43_DMA32_TXSTAT_DISABLED) {
 534				i = -1;
 535				break;
 536			}
 537		}
 538		msleep(1);
 539	}
 540	if (i != -1) {
 541		b43err(dev->wl, "DMA TX reset timed out\n");
 542		return -ENODEV;
 543	}
 544	/* ensure the reset is completed. */
 545	msleep(1);
 546
 547	return 0;
 548}
 549
 550/* Check if a DMA mapping address is invalid. */
 551static bool b43_dma_mapping_error(struct b43_dmaring *ring,
 552				  dma_addr_t addr,
 553				  size_t buffersize, bool dma_to_device)
 554{
 555	if (unlikely(dma_mapping_error(ring->dev->dev->dma_dev, addr)))
 556		return 1;
 557
 558	switch (ring->type) {
 559	case B43_DMA_30BIT:
 560		if ((u64)addr + buffersize > (1ULL << 30))
 561			goto address_error;
 562		break;
 563	case B43_DMA_32BIT:
 564		if ((u64)addr + buffersize > (1ULL << 32))
 565			goto address_error;
 566		break;
 567	case B43_DMA_64BIT:
 568		/* Currently we can't have addresses beyond
 569		 * 64bit in the kernel. */
 570		break;
 571	}
 572
 573	/* The address is OK. */
 574	return 0;
 575
 576address_error:
 577	/* We can't support this address. Unmap it again. */
 578	unmap_descbuffer(ring, addr, buffersize, dma_to_device);
 579
 580	return 1;
 581}
 582
 583static bool b43_rx_buffer_is_poisoned(struct b43_dmaring *ring, struct sk_buff *skb)
 584{
 585	unsigned char *f = skb->data + ring->frameoffset;
 586
 587	return ((f[0] & f[1] & f[2] & f[3] & f[4] & f[5] & f[6] & f[7]) == 0xFF);
 588}
 589
 590static void b43_poison_rx_buffer(struct b43_dmaring *ring, struct sk_buff *skb)
 591{
 592	struct b43_rxhdr_fw4 *rxhdr;
 593	unsigned char *frame;
 594
 595	/* This poisons the RX buffer to detect DMA failures. */
 596
 597	rxhdr = (struct b43_rxhdr_fw4 *)(skb->data);
 598	rxhdr->frame_len = 0;
 599
 600	B43_WARN_ON(ring->rx_buffersize < ring->frameoffset + sizeof(struct b43_plcp_hdr6) + 2);
 601	frame = skb->data + ring->frameoffset;
 602	memset(frame, 0xFF, sizeof(struct b43_plcp_hdr6) + 2 /* padding */);
 603}
 604
 605static int setup_rx_descbuffer(struct b43_dmaring *ring,
 606			       struct b43_dmadesc_generic *desc,
 607			       struct b43_dmadesc_meta *meta, gfp_t gfp_flags)
 608{
 609	dma_addr_t dmaaddr;
 610	struct sk_buff *skb;
 611
 612	B43_WARN_ON(ring->tx);
 613
 614	skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 615	if (unlikely(!skb))
 616		return -ENOMEM;
 617	b43_poison_rx_buffer(ring, skb);
 618	dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
 619	if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 620		/* ugh. try to realloc in zone_dma */
 621		gfp_flags |= GFP_DMA;
 622
 623		dev_kfree_skb_any(skb);
 624
 625		skb = __dev_alloc_skb(ring->rx_buffersize, gfp_flags);
 626		if (unlikely(!skb))
 627			return -ENOMEM;
 628		b43_poison_rx_buffer(ring, skb);
 629		dmaaddr = map_descbuffer(ring, skb->data,
 630					 ring->rx_buffersize, 0);
 631		if (b43_dma_mapping_error(ring, dmaaddr, ring->rx_buffersize, 0)) {
 632			b43err(ring->dev->wl, "RX DMA buffer allocation failed\n");
 633			dev_kfree_skb_any(skb);
 634			return -EIO;
 635		}
 636	}
 637
 638	meta->skb = skb;
 639	meta->dmaaddr = dmaaddr;
 640	ring->ops->fill_descriptor(ring, desc, dmaaddr,
 641				   ring->rx_buffersize, 0, 0, 0);
 642
 643	return 0;
 644}
 645
 646/* Allocate the initial descbuffers.
 647 * This is used for an RX ring only.
 648 */
 649static int alloc_initial_descbuffers(struct b43_dmaring *ring)
 650{
 651	int i, err = -ENOMEM;
 652	struct b43_dmadesc_generic *desc;
 653	struct b43_dmadesc_meta *meta;
 654
 655	for (i = 0; i < ring->nr_slots; i++) {
 656		desc = ring->ops->idx2desc(ring, i, &meta);
 657
 658		err = setup_rx_descbuffer(ring, desc, meta, GFP_KERNEL);
 659		if (err) {
 660			b43err(ring->dev->wl,
 661			       "Failed to allocate initial descbuffers\n");
 662			goto err_unwind;
 663		}
 664	}
 665	mb();
 666	ring->used_slots = ring->nr_slots;
 667	err = 0;
 668      out:
 669	return err;
 670
 671      err_unwind:
 672	for (i--; i >= 0; i--) {
 673		desc = ring->ops->idx2desc(ring, i, &meta);
 674
 675		unmap_descbuffer(ring, meta->dmaaddr, ring->rx_buffersize, 0);
 676		dev_kfree_skb(meta->skb);
 677	}
 678	goto out;
 679}
 680
 681/* Do initial setup of the DMA controller.
 682 * Reset the controller, write the ring busaddress
 683 * and switch the "enable" bit on.
 684 */
 685static int dmacontroller_setup(struct b43_dmaring *ring)
 686{
 687	int err = 0;
 688	u32 value;
 689	u32 addrext;
 
 690	bool parity = ring->dev->dma.parity;
 691	u32 addrlo;
 692	u32 addrhi;
 693
 694	if (ring->tx) {
 695		if (ring->type == B43_DMA_64BIT) {
 696			u64 ringbase = (u64) (ring->dmabase);
 697			addrext = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_EXT);
 698			addrlo = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_LOW);
 699			addrhi = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_HIGH);
 700
 
 
 701			value = B43_DMA64_TXENABLE;
 702			value |= (addrext << B43_DMA64_TXADDREXT_SHIFT)
 703			    & B43_DMA64_TXADDREXT_MASK;
 704			if (!parity)
 705				value |= B43_DMA64_TXPARITYDISABLE;
 706			b43_dma_write(ring, B43_DMA64_TXCTL, value);
 707			b43_dma_write(ring, B43_DMA64_TXRINGLO, addrlo);
 708			b43_dma_write(ring, B43_DMA64_TXRINGHI, addrhi);
 
 
 
 
 709		} else {
 710			u32 ringbase = (u32) (ring->dmabase);
 711			addrext = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_EXT);
 712			addrlo = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_LOW);
 713
 
 
 714			value = B43_DMA32_TXENABLE;
 715			value |= (addrext << B43_DMA32_TXADDREXT_SHIFT)
 716			    & B43_DMA32_TXADDREXT_MASK;
 717			if (!parity)
 718				value |= B43_DMA32_TXPARITYDISABLE;
 719			b43_dma_write(ring, B43_DMA32_TXCTL, value);
 720			b43_dma_write(ring, B43_DMA32_TXRING, addrlo);
 
 
 721		}
 722	} else {
 723		err = alloc_initial_descbuffers(ring);
 724		if (err)
 725			goto out;
 726		if (ring->type == B43_DMA_64BIT) {
 727			u64 ringbase = (u64) (ring->dmabase);
 728			addrext = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_EXT);
 729			addrlo = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_LOW);
 730			addrhi = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_HIGH);
 731
 
 
 732			value = (ring->frameoffset << B43_DMA64_RXFROFF_SHIFT);
 733			value |= B43_DMA64_RXENABLE;
 734			value |= (addrext << B43_DMA64_RXADDREXT_SHIFT)
 735			    & B43_DMA64_RXADDREXT_MASK;
 736			if (!parity)
 737				value |= B43_DMA64_RXPARITYDISABLE;
 738			b43_dma_write(ring, B43_DMA64_RXCTL, value);
 739			b43_dma_write(ring, B43_DMA64_RXRINGLO, addrlo);
 740			b43_dma_write(ring, B43_DMA64_RXRINGHI, addrhi);
 
 
 
 
 741			b43_dma_write(ring, B43_DMA64_RXINDEX, ring->nr_slots *
 742				      sizeof(struct b43_dmadesc64));
 743		} else {
 744			u32 ringbase = (u32) (ring->dmabase);
 745			addrext = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_EXT);
 746			addrlo = b43_dma_address(&ring->dev->dma, ringbase, B43_DMA_ADDR_LOW);
 747
 
 
 748			value = (ring->frameoffset << B43_DMA32_RXFROFF_SHIFT);
 749			value |= B43_DMA32_RXENABLE;
 750			value |= (addrext << B43_DMA32_RXADDREXT_SHIFT)
 751			    & B43_DMA32_RXADDREXT_MASK;
 752			if (!parity)
 753				value |= B43_DMA32_RXPARITYDISABLE;
 754			b43_dma_write(ring, B43_DMA32_RXCTL, value);
 755			b43_dma_write(ring, B43_DMA32_RXRING, addrlo);
 
 
 756			b43_dma_write(ring, B43_DMA32_RXINDEX, ring->nr_slots *
 757				      sizeof(struct b43_dmadesc32));
 758		}
 759	}
 760
 761out:
 762	return err;
 763}
 764
 765/* Shutdown the DMA controller. */
 766static void dmacontroller_cleanup(struct b43_dmaring *ring)
 767{
 768	if (ring->tx) {
 769		b43_dmacontroller_tx_reset(ring->dev, ring->mmio_base,
 770					   ring->type);
 771		if (ring->type == B43_DMA_64BIT) {
 772			b43_dma_write(ring, B43_DMA64_TXRINGLO, 0);
 773			b43_dma_write(ring, B43_DMA64_TXRINGHI, 0);
 774		} else
 775			b43_dma_write(ring, B43_DMA32_TXRING, 0);
 776	} else {
 777		b43_dmacontroller_rx_reset(ring->dev, ring->mmio_base,
 778					   ring->type);
 779		if (ring->type == B43_DMA_64BIT) {
 780			b43_dma_write(ring, B43_DMA64_RXRINGLO, 0);
 781			b43_dma_write(ring, B43_DMA64_RXRINGHI, 0);
 782		} else
 783			b43_dma_write(ring, B43_DMA32_RXRING, 0);
 784	}
 785}
 786
 787static void free_all_descbuffers(struct b43_dmaring *ring)
 788{
 789	struct b43_dmadesc_meta *meta;
 790	int i;
 791
 792	if (!ring->used_slots)
 793		return;
 794	for (i = 0; i < ring->nr_slots; i++) {
 795		/* get meta - ignore returned value */
 796		ring->ops->idx2desc(ring, i, &meta);
 797
 798		if (!meta->skb || b43_dma_ptr_is_poisoned(meta->skb)) {
 799			B43_WARN_ON(!ring->tx);
 800			continue;
 801		}
 802		if (ring->tx) {
 803			unmap_descbuffer(ring, meta->dmaaddr,
 804					 meta->skb->len, 1);
 805		} else {
 806			unmap_descbuffer(ring, meta->dmaaddr,
 807					 ring->rx_buffersize, 0);
 808		}
 809		free_descriptor_buffer(ring, meta);
 810	}
 811}
 812
 813static u64 supported_dma_mask(struct b43_wldev *dev)
 814{
 815	u32 tmp;
 816	u16 mmio_base;
 817
 818	switch (dev->dev->bus_type) {
 819#ifdef CONFIG_B43_BCMA
 820	case B43_BUS_BCMA:
 821		tmp = bcma_aread32(dev->dev->bdev, BCMA_IOST);
 822		if (tmp & BCMA_IOST_DMA64)
 823			return DMA_BIT_MASK(64);
 824		break;
 825#endif
 826#ifdef CONFIG_B43_SSB
 827	case B43_BUS_SSB:
 828		tmp = ssb_read32(dev->dev->sdev, SSB_TMSHIGH);
 829		if (tmp & SSB_TMSHIGH_DMA64)
 830			return DMA_BIT_MASK(64);
 831		break;
 832#endif
 833	}
 834
 835	mmio_base = b43_dmacontroller_base(0, 0);
 836	b43_write32(dev, mmio_base + B43_DMA32_TXCTL, B43_DMA32_TXADDREXT_MASK);
 837	tmp = b43_read32(dev, mmio_base + B43_DMA32_TXCTL);
 838	if (tmp & B43_DMA32_TXADDREXT_MASK)
 839		return DMA_BIT_MASK(32);
 840
 841	return DMA_BIT_MASK(30);
 842}
 843
 844static enum b43_dmatype dma_mask_to_engine_type(u64 dmamask)
 845{
 846	if (dmamask == DMA_BIT_MASK(30))
 847		return B43_DMA_30BIT;
 848	if (dmamask == DMA_BIT_MASK(32))
 849		return B43_DMA_32BIT;
 850	if (dmamask == DMA_BIT_MASK(64))
 851		return B43_DMA_64BIT;
 852	B43_WARN_ON(1);
 853	return B43_DMA_30BIT;
 854}
 855
 856/* Main initialization function. */
 857static
 858struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
 859				      int controller_index,
 860				      int for_tx,
 861				      enum b43_dmatype type)
 862{
 863	struct b43_dmaring *ring;
 864	int i, err;
 865	dma_addr_t dma_test;
 866
 867	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
 868	if (!ring)
 869		goto out;
 870
 871	ring->nr_slots = B43_RXRING_SLOTS;
 872	if (for_tx)
 873		ring->nr_slots = B43_TXRING_SLOTS;
 874
 875	ring->meta = kcalloc(ring->nr_slots, sizeof(struct b43_dmadesc_meta),
 876			     GFP_KERNEL);
 877	if (!ring->meta)
 878		goto err_kfree_ring;
 879	for (i = 0; i < ring->nr_slots; i++)
 880		ring->meta->skb = B43_DMA_PTR_POISON;
 881
 882	ring->type = type;
 883	ring->dev = dev;
 884	ring->mmio_base = b43_dmacontroller_base(type, controller_index);
 885	ring->index = controller_index;
 886	if (type == B43_DMA_64BIT)
 887		ring->ops = &dma64_ops;
 888	else
 889		ring->ops = &dma32_ops;
 890	if (for_tx) {
 891		ring->tx = true;
 892		ring->current_slot = -1;
 893	} else {
 894		if (ring->index == 0) {
 895			switch (dev->fw.hdr_format) {
 896			case B43_FW_HDR_598:
 897				ring->rx_buffersize = B43_DMA0_RX_FW598_BUFSIZE;
 898				ring->frameoffset = B43_DMA0_RX_FW598_FO;
 899				break;
 900			case B43_FW_HDR_410:
 901			case B43_FW_HDR_351:
 902				ring->rx_buffersize = B43_DMA0_RX_FW351_BUFSIZE;
 903				ring->frameoffset = B43_DMA0_RX_FW351_FO;
 904				break;
 905			}
 906		} else
 907			B43_WARN_ON(1);
 908	}
 909#ifdef CONFIG_B43_DEBUG
 910	ring->last_injected_overflow = jiffies;
 911#endif
 912
 913	if (for_tx) {
 914		/* Assumption: B43_TXRING_SLOTS can be divided by TX_SLOTS_PER_FRAME */
 915		BUILD_BUG_ON(B43_TXRING_SLOTS % TX_SLOTS_PER_FRAME != 0);
 916
 917		ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 918					    b43_txhdr_size(dev),
 919					    GFP_KERNEL);
 920		if (!ring->txhdr_cache)
 921			goto err_kfree_meta;
 922
 923		/* test for ability to dma to txhdr_cache */
 924		dma_test = dma_map_single(dev->dev->dma_dev,
 925					  ring->txhdr_cache,
 926					  b43_txhdr_size(dev),
 927					  DMA_TO_DEVICE);
 928
 929		if (b43_dma_mapping_error(ring, dma_test,
 930					  b43_txhdr_size(dev), 1)) {
 931			/* ugh realloc */
 932			kfree(ring->txhdr_cache);
 933			ring->txhdr_cache = kcalloc(ring->nr_slots / TX_SLOTS_PER_FRAME,
 934						    b43_txhdr_size(dev),
 935						    GFP_KERNEL | GFP_DMA);
 936			if (!ring->txhdr_cache)
 937				goto err_kfree_meta;
 938
 939			dma_test = dma_map_single(dev->dev->dma_dev,
 940						  ring->txhdr_cache,
 941						  b43_txhdr_size(dev),
 942						  DMA_TO_DEVICE);
 943
 944			if (b43_dma_mapping_error(ring, dma_test,
 945						  b43_txhdr_size(dev), 1)) {
 946
 947				b43err(dev->wl,
 948				       "TXHDR DMA allocation failed\n");
 949				goto err_kfree_txhdr_cache;
 950			}
 951		}
 952
 953		dma_unmap_single(dev->dev->dma_dev,
 954				 dma_test, b43_txhdr_size(dev),
 955				 DMA_TO_DEVICE);
 956	}
 957
 958	err = alloc_ringmemory(ring);
 959	if (err)
 960		goto err_kfree_txhdr_cache;
 961	err = dmacontroller_setup(ring);
 962	if (err)
 963		goto err_free_ringmemory;
 964
 965      out:
 966	return ring;
 967
 968      err_free_ringmemory:
 969	free_ringmemory(ring);
 970      err_kfree_txhdr_cache:
 971	kfree(ring->txhdr_cache);
 972      err_kfree_meta:
 973	kfree(ring->meta);
 974      err_kfree_ring:
 975	kfree(ring);
 976	ring = NULL;
 977	goto out;
 978}
 979
 980#define divide(a, b)	({	\
 981	typeof(a) __a = a;	\
 982	do_div(__a, b);		\
 983	__a;			\
 984  })
 985
 986#define modulo(a, b)	({	\
 987	typeof(a) __a = a;	\
 988	do_div(__a, b);		\
 989  })
 990
 991/* Main cleanup function. */
 992static void b43_destroy_dmaring(struct b43_dmaring *ring,
 993				const char *ringname)
 994{
 995	if (!ring)
 996		return;
 997
 998#ifdef CONFIG_B43_DEBUG
 999	{
1000		/* Print some statistics. */
1001		u64 failed_packets = ring->nr_failed_tx_packets;
1002		u64 succeed_packets = ring->nr_succeed_tx_packets;
1003		u64 nr_packets = failed_packets + succeed_packets;
1004		u64 permille_failed = 0, average_tries = 0;
1005
1006		if (nr_packets)
1007			permille_failed = divide(failed_packets * 1000, nr_packets);
1008		if (nr_packets)
1009			average_tries = divide(ring->nr_total_packet_tries * 100, nr_packets);
1010
1011		b43dbg(ring->dev->wl, "DMA-%u %s: "
1012		       "Used slots %d/%d, Failed frames %llu/%llu = %llu.%01llu%%, "
1013		       "Average tries %llu.%02llu\n",
1014		       (unsigned int)(ring->type), ringname,
1015		       ring->max_used_slots,
1016		       ring->nr_slots,
1017		       (unsigned long long)failed_packets,
1018		       (unsigned long long)nr_packets,
1019		       (unsigned long long)divide(permille_failed, 10),
1020		       (unsigned long long)modulo(permille_failed, 10),
1021		       (unsigned long long)divide(average_tries, 100),
1022		       (unsigned long long)modulo(average_tries, 100));
1023	}
1024#endif /* DEBUG */
1025
1026	/* Device IRQs are disabled prior entering this function,
1027	 * so no need to take care of concurrency with rx handler stuff.
1028	 */
1029	dmacontroller_cleanup(ring);
1030	free_all_descbuffers(ring);
1031	free_ringmemory(ring);
1032
1033	kfree(ring->txhdr_cache);
1034	kfree(ring->meta);
1035	kfree(ring);
1036}
1037
1038#define destroy_ring(dma, ring) do {				\
1039	b43_destroy_dmaring((dma)->ring, __stringify(ring));	\
1040	(dma)->ring = NULL;					\
1041    } while (0)
1042
1043void b43_dma_free(struct b43_wldev *dev)
1044{
1045	struct b43_dma *dma;
1046
1047	if (b43_using_pio_transfers(dev))
1048		return;
1049	dma = &dev->dma;
1050
1051	destroy_ring(dma, rx_ring);
1052	destroy_ring(dma, tx_ring_AC_BK);
1053	destroy_ring(dma, tx_ring_AC_BE);
1054	destroy_ring(dma, tx_ring_AC_VI);
1055	destroy_ring(dma, tx_ring_AC_VO);
1056	destroy_ring(dma, tx_ring_mcast);
1057}
1058
1059static int b43_dma_set_mask(struct b43_wldev *dev, u64 mask)
1060{
1061	u64 orig_mask = mask;
1062	bool fallback = false;
1063	int err;
1064
1065	/* Try to set the DMA mask. If it fails, try falling back to a
1066	 * lower mask, as we can always also support a lower one. */
1067	while (1) {
1068		err = dma_set_mask_and_coherent(dev->dev->dma_dev, mask);
1069		if (!err)
1070			break;
 
 
 
1071		if (mask == DMA_BIT_MASK(64)) {
1072			mask = DMA_BIT_MASK(32);
1073			fallback = true;
1074			continue;
1075		}
1076		if (mask == DMA_BIT_MASK(32)) {
1077			mask = DMA_BIT_MASK(30);
1078			fallback = true;
1079			continue;
1080		}
1081		b43err(dev->wl, "The machine/kernel does not support "
1082		       "the required %u-bit DMA mask\n",
1083		       (unsigned int)dma_mask_to_engine_type(orig_mask));
1084		return -EOPNOTSUPP;
1085	}
1086	if (fallback) {
1087		b43info(dev->wl, "DMA mask fallback from %u-bit to %u-bit\n",
1088			(unsigned int)dma_mask_to_engine_type(orig_mask),
1089			(unsigned int)dma_mask_to_engine_type(mask));
1090	}
1091
1092	return 0;
1093}
1094
1095/* Some hardware with 64-bit DMA seems to be bugged and looks for translation
1096 * bit in low address word instead of high one.
1097 */
1098static bool b43_dma_translation_in_low_word(struct b43_wldev *dev,
1099					    enum b43_dmatype type)
1100{
1101	if (type != B43_DMA_64BIT)
1102		return 1;
1103
1104#ifdef CONFIG_B43_SSB
1105	if (dev->dev->bus_type == B43_BUS_SSB &&
1106	    dev->dev->sdev->bus->bustype == SSB_BUSTYPE_PCI &&
1107	    !(pci_is_pcie(dev->dev->sdev->bus->host_pci) &&
1108	      ssb_read32(dev->dev->sdev, SSB_TMSHIGH) & SSB_TMSHIGH_DMA64))
1109			return 1;
1110#endif
1111	return 0;
1112}
1113
1114int b43_dma_init(struct b43_wldev *dev)
1115{
1116	struct b43_dma *dma = &dev->dma;
1117	int err;
1118	u64 dmamask;
1119	enum b43_dmatype type;
1120
1121	dmamask = supported_dma_mask(dev);
1122	type = dma_mask_to_engine_type(dmamask);
1123	err = b43_dma_set_mask(dev, dmamask);
1124	if (err)
1125		return err;
1126
1127	switch (dev->dev->bus_type) {
1128#ifdef CONFIG_B43_BCMA
1129	case B43_BUS_BCMA:
1130		dma->translation = bcma_core_dma_translation(dev->dev->bdev);
1131		break;
1132#endif
1133#ifdef CONFIG_B43_SSB
1134	case B43_BUS_SSB:
1135		dma->translation = ssb_dma_translation(dev->dev->sdev);
1136		break;
1137#endif
1138	}
1139	dma->translation_in_low = b43_dma_translation_in_low_word(dev, type);
1140
1141	dma->parity = true;
1142#ifdef CONFIG_B43_BCMA
1143	/* TODO: find out which SSB devices need disabling parity */
1144	if (dev->dev->bus_type == B43_BUS_BCMA)
1145		dma->parity = false;
1146#endif
1147
1148	err = -ENOMEM;
1149	/* setup TX DMA channels. */
1150	dma->tx_ring_AC_BK = b43_setup_dmaring(dev, 0, 1, type);
1151	if (!dma->tx_ring_AC_BK)
1152		goto out;
1153
1154	dma->tx_ring_AC_BE = b43_setup_dmaring(dev, 1, 1, type);
1155	if (!dma->tx_ring_AC_BE)
1156		goto err_destroy_bk;
1157
1158	dma->tx_ring_AC_VI = b43_setup_dmaring(dev, 2, 1, type);
1159	if (!dma->tx_ring_AC_VI)
1160		goto err_destroy_be;
1161
1162	dma->tx_ring_AC_VO = b43_setup_dmaring(dev, 3, 1, type);
1163	if (!dma->tx_ring_AC_VO)
1164		goto err_destroy_vi;
1165
1166	dma->tx_ring_mcast = b43_setup_dmaring(dev, 4, 1, type);
1167	if (!dma->tx_ring_mcast)
1168		goto err_destroy_vo;
1169
1170	/* setup RX DMA channel. */
1171	dma->rx_ring = b43_setup_dmaring(dev, 0, 0, type);
1172	if (!dma->rx_ring)
1173		goto err_destroy_mcast;
1174
1175	/* No support for the TX status DMA ring. */
1176	B43_WARN_ON(dev->dev->core_rev < 5);
1177
1178	b43dbg(dev->wl, "%u-bit DMA initialized\n",
1179	       (unsigned int)type);
1180	err = 0;
1181out:
1182	return err;
1183
1184err_destroy_mcast:
1185	destroy_ring(dma, tx_ring_mcast);
1186err_destroy_vo:
1187	destroy_ring(dma, tx_ring_AC_VO);
1188err_destroy_vi:
1189	destroy_ring(dma, tx_ring_AC_VI);
1190err_destroy_be:
1191	destroy_ring(dma, tx_ring_AC_BE);
1192err_destroy_bk:
1193	destroy_ring(dma, tx_ring_AC_BK);
1194	return err;
1195}
1196
1197/* Generate a cookie for the TX header. */
1198static u16 generate_cookie(struct b43_dmaring *ring, int slot)
1199{
1200	u16 cookie;
1201
1202	/* Use the upper 4 bits of the cookie as
1203	 * DMA controller ID and store the slot number
1204	 * in the lower 12 bits.
1205	 * Note that the cookie must never be 0, as this
1206	 * is a special value used in RX path.
1207	 * It can also not be 0xFFFF because that is special
1208	 * for multicast frames.
1209	 */
1210	cookie = (((u16)ring->index + 1) << 12);
1211	B43_WARN_ON(slot & ~0x0FFF);
1212	cookie |= (u16)slot;
1213
1214	return cookie;
1215}
1216
1217/* Inspect a cookie and find out to which controller/slot it belongs. */
1218static
1219struct b43_dmaring *parse_cookie(struct b43_wldev *dev, u16 cookie, int *slot)
1220{
1221	struct b43_dma *dma = &dev->dma;
1222	struct b43_dmaring *ring = NULL;
1223
1224	switch (cookie & 0xF000) {
1225	case 0x1000:
1226		ring = dma->tx_ring_AC_BK;
1227		break;
1228	case 0x2000:
1229		ring = dma->tx_ring_AC_BE;
1230		break;
1231	case 0x3000:
1232		ring = dma->tx_ring_AC_VI;
1233		break;
1234	case 0x4000:
1235		ring = dma->tx_ring_AC_VO;
1236		break;
1237	case 0x5000:
1238		ring = dma->tx_ring_mcast;
1239		break;
1240	}
1241	*slot = (cookie & 0x0FFF);
1242	if (unlikely(!ring || *slot < 0 || *slot >= ring->nr_slots)) {
1243		b43dbg(dev->wl, "TX-status contains "
1244		       "invalid cookie: 0x%04X\n", cookie);
1245		return NULL;
1246	}
1247
1248	return ring;
1249}
1250
1251static int dma_tx_fragment(struct b43_dmaring *ring,
1252			   struct sk_buff *skb)
1253{
1254	const struct b43_dma_ops *ops = ring->ops;
1255	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1256	struct b43_private_tx_info *priv_info = b43_get_priv_tx_info(info);
1257	u8 *header;
1258	int slot, old_top_slot, old_used_slots;
1259	int err;
1260	struct b43_dmadesc_generic *desc;
1261	struct b43_dmadesc_meta *meta;
1262	struct b43_dmadesc_meta *meta_hdr;
1263	u16 cookie;
1264	size_t hdrsize = b43_txhdr_size(ring->dev);
1265
1266	/* Important note: If the number of used DMA slots per TX frame
1267	 * is changed here, the TX_SLOTS_PER_FRAME definition at the top of
1268	 * the file has to be updated, too!
1269	 */
1270
1271	old_top_slot = ring->current_slot;
1272	old_used_slots = ring->used_slots;
1273
1274	/* Get a slot for the header. */
1275	slot = request_slot(ring);
1276	desc = ops->idx2desc(ring, slot, &meta_hdr);
1277	memset(meta_hdr, 0, sizeof(*meta_hdr));
1278
1279	header = &(ring->txhdr_cache[(slot / TX_SLOTS_PER_FRAME) * hdrsize]);
1280	cookie = generate_cookie(ring, slot);
1281	err = b43_generate_txhdr(ring->dev, header,
1282				 skb, info, cookie);
1283	if (unlikely(err)) {
1284		ring->current_slot = old_top_slot;
1285		ring->used_slots = old_used_slots;
1286		return err;
1287	}
1288
1289	meta_hdr->dmaaddr = map_descbuffer(ring, (unsigned char *)header,
1290					   hdrsize, 1);
1291	if (b43_dma_mapping_error(ring, meta_hdr->dmaaddr, hdrsize, 1)) {
1292		ring->current_slot = old_top_slot;
1293		ring->used_slots = old_used_slots;
1294		return -EIO;
1295	}
1296	ops->fill_descriptor(ring, desc, meta_hdr->dmaaddr,
1297			     hdrsize, 1, 0, 0);
1298
1299	/* Get a slot for the payload. */
1300	slot = request_slot(ring);
1301	desc = ops->idx2desc(ring, slot, &meta);
1302	memset(meta, 0, sizeof(*meta));
1303
1304	meta->skb = skb;
1305	meta->is_last_fragment = true;
1306	priv_info->bouncebuffer = NULL;
1307
1308	meta->dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
1309	/* create a bounce buffer in zone_dma on mapping failure. */
1310	if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1311		priv_info->bouncebuffer = kmemdup(skb->data, skb->len,
1312						  GFP_ATOMIC | GFP_DMA);
1313		if (!priv_info->bouncebuffer) {
1314			ring->current_slot = old_top_slot;
1315			ring->used_slots = old_used_slots;
1316			err = -ENOMEM;
1317			goto out_unmap_hdr;
1318		}
1319
1320		meta->dmaaddr = map_descbuffer(ring, priv_info->bouncebuffer, skb->len, 1);
1321		if (b43_dma_mapping_error(ring, meta->dmaaddr, skb->len, 1)) {
1322			kfree(priv_info->bouncebuffer);
1323			priv_info->bouncebuffer = NULL;
1324			ring->current_slot = old_top_slot;
1325			ring->used_slots = old_used_slots;
1326			err = -EIO;
1327			goto out_unmap_hdr;
1328		}
1329	}
1330
1331	ops->fill_descriptor(ring, desc, meta->dmaaddr, skb->len, 0, 1, 1);
1332
1333	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1334		/* Tell the firmware about the cookie of the last
1335		 * mcast frame, so it can clear the more-data bit in it. */
1336		b43_shm_write16(ring->dev, B43_SHM_SHARED,
1337				B43_SHM_SH_MCASTCOOKIE, cookie);
1338	}
1339	/* Now transfer the whole frame. */
1340	wmb();
1341	ops->poke_tx(ring, next_slot(ring, slot));
1342	return 0;
1343
1344out_unmap_hdr:
1345	unmap_descbuffer(ring, meta_hdr->dmaaddr,
1346			 hdrsize, 1);
1347	return err;
1348}
1349
1350static inline int should_inject_overflow(struct b43_dmaring *ring)
1351{
1352#ifdef CONFIG_B43_DEBUG
1353	if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
1354		/* Check if we should inject another ringbuffer overflow
1355		 * to test handling of this situation in the stack. */
1356		unsigned long next_overflow;
1357
1358		next_overflow = ring->last_injected_overflow + HZ;
1359		if (time_after(jiffies, next_overflow)) {
1360			ring->last_injected_overflow = jiffies;
1361			b43dbg(ring->dev->wl,
1362			       "Injecting TX ring overflow on "
1363			       "DMA controller %d\n", ring->index);
1364			return 1;
1365		}
1366	}
1367#endif /* CONFIG_B43_DEBUG */
1368	return 0;
1369}
1370
1371/* Static mapping of mac80211's queues (priorities) to b43 DMA rings. */
1372static struct b43_dmaring *select_ring_by_priority(struct b43_wldev *dev,
1373						   u8 queue_prio)
1374{
1375	struct b43_dmaring *ring;
1376
1377	if (dev->qos_enabled) {
1378		/* 0 = highest priority */
1379		switch (queue_prio) {
1380		default:
1381			B43_WARN_ON(1);
1382			/* fallthrough */
1383		case 0:
1384			ring = dev->dma.tx_ring_AC_VO;
1385			break;
1386		case 1:
1387			ring = dev->dma.tx_ring_AC_VI;
1388			break;
1389		case 2:
1390			ring = dev->dma.tx_ring_AC_BE;
1391			break;
1392		case 3:
1393			ring = dev->dma.tx_ring_AC_BK;
1394			break;
1395		}
1396	} else
1397		ring = dev->dma.tx_ring_AC_BE;
1398
1399	return ring;
1400}
1401
1402int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
1403{
1404	struct b43_dmaring *ring;
1405	struct ieee80211_hdr *hdr;
1406	int err = 0;
1407	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1408
1409	hdr = (struct ieee80211_hdr *)skb->data;
1410	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
1411		/* The multicast ring will be sent after the DTIM */
1412		ring = dev->dma.tx_ring_mcast;
1413		/* Set the more-data bit. Ucode will clear it on
1414		 * the last frame for us. */
1415		hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1416	} else {
1417		/* Decide by priority where to put this frame. */
1418		ring = select_ring_by_priority(
1419			dev, skb_get_queue_mapping(skb));
1420	}
1421
1422	B43_WARN_ON(!ring->tx);
1423
1424	if (unlikely(ring->stopped)) {
1425		/* We get here only because of a bug in mac80211.
1426		 * Because of a race, one packet may be queued after
1427		 * the queue is stopped, thus we got called when we shouldn't.
1428		 * For now, just refuse the transmit. */
1429		if (b43_debug(dev, B43_DBG_DMAVERBOSE))
1430			b43err(dev->wl, "Packet after queue stopped\n");
1431		err = -ENOSPC;
1432		goto out;
1433	}
1434
1435	if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
1436		/* If we get here, we have a real error with the queue
1437		 * full, but queues not stopped. */
1438		b43err(dev->wl, "DMA queue overflow\n");
1439		err = -ENOSPC;
1440		goto out;
1441	}
1442
1443	/* Assign the queue number to the ring (if not already done before)
1444	 * so TX status handling can use it. The queue to ring mapping is
1445	 * static, so we don't need to store it per frame. */
1446	ring->queue_prio = skb_get_queue_mapping(skb);
1447
1448	err = dma_tx_fragment(ring, skb);
1449	if (unlikely(err == -ENOKEY)) {
1450		/* Drop this packet, as we don't have the encryption key
1451		 * anymore and must not transmit it unencrypted. */
1452		ieee80211_free_txskb(dev->wl->hw, skb);
1453		err = 0;
1454		goto out;
1455	}
1456	if (unlikely(err)) {
1457		b43err(dev->wl, "DMA tx mapping failure\n");
1458		goto out;
1459	}
1460	if ((free_slots(ring) < TX_SLOTS_PER_FRAME) ||
1461	    should_inject_overflow(ring)) {
1462		/* This TX ring is full. */
1463		unsigned int skb_mapping = skb_get_queue_mapping(skb);
1464		ieee80211_stop_queue(dev->wl->hw, skb_mapping);
1465		dev->wl->tx_queue_stopped[skb_mapping] = 1;
1466		ring->stopped = true;
1467		if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1468			b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
1469		}
1470	}
1471out:
1472
1473	return err;
1474}
1475
1476void b43_dma_handle_txstatus(struct b43_wldev *dev,
1477			     const struct b43_txstatus *status)
1478{
1479	const struct b43_dma_ops *ops;
1480	struct b43_dmaring *ring;
1481	struct b43_dmadesc_meta *meta;
1482	static const struct b43_txstatus fake; /* filled with 0 */
1483	const struct b43_txstatus *txstat;
1484	int slot, firstused;
1485	bool frame_succeed;
1486	int skip;
1487	static u8 err_out1, err_out2;
1488
1489	ring = parse_cookie(dev, status->cookie, &slot);
1490	if (unlikely(!ring))
1491		return;
1492	B43_WARN_ON(!ring->tx);
1493
1494	/* Sanity check: TX packets are processed in-order on one ring.
1495	 * Check if the slot deduced from the cookie really is the first
1496	 * used slot. */
1497	firstused = ring->current_slot - ring->used_slots + 1;
1498	if (firstused < 0)
1499		firstused = ring->nr_slots + firstused;
1500
1501	skip = 0;
1502	if (unlikely(slot != firstused)) {
1503		/* This possibly is a firmware bug and will result in
1504		 * malfunction, memory leaks and/or stall of DMA functionality.
1505		 */
1506		if (slot == next_slot(ring, next_slot(ring, firstused))) {
1507			/* If a single header/data pair was missed, skip over
1508			 * the first two slots in an attempt to recover.
1509			 */
1510			slot = firstused;
1511			skip = 2;
1512			if (!err_out1) {
1513				/* Report the error once. */
1514				b43dbg(dev->wl,
1515				       "Skip on DMA ring %d slot %d.\n",
1516				       ring->index, slot);
1517				err_out1 = 1;
1518			}
1519		} else {
1520			/* More than a single header/data pair were missed.
1521			 * Report this error once.
1522			 */
1523			if (!err_out2)
1524				b43dbg(dev->wl,
1525				       "Out of order TX status report on DMA ring %d. Expected %d, but got %d\n",
1526				       ring->index, firstused, slot);
1527			err_out2 = 1;
1528			return;
1529		}
1530	}
1531
1532	ops = ring->ops;
1533	while (1) {
1534		B43_WARN_ON(slot < 0 || slot >= ring->nr_slots);
1535		/* get meta - ignore returned value */
1536		ops->idx2desc(ring, slot, &meta);
1537
1538		if (b43_dma_ptr_is_poisoned(meta->skb)) {
1539			b43dbg(dev->wl, "Poisoned TX slot %d (first=%d) "
1540			       "on ring %d\n",
1541			       slot, firstused, ring->index);
1542			break;
1543		}
1544
1545		if (meta->skb) {
1546			struct b43_private_tx_info *priv_info =
1547			     b43_get_priv_tx_info(IEEE80211_SKB_CB(meta->skb));
1548
1549			unmap_descbuffer(ring, meta->dmaaddr,
1550					 meta->skb->len, 1);
1551			kfree(priv_info->bouncebuffer);
1552			priv_info->bouncebuffer = NULL;
1553		} else {
1554			unmap_descbuffer(ring, meta->dmaaddr,
1555					 b43_txhdr_size(dev), 1);
1556		}
1557
1558		if (meta->is_last_fragment) {
1559			struct ieee80211_tx_info *info;
1560
1561			if (unlikely(!meta->skb)) {
1562				/* This is a scatter-gather fragment of a frame,
1563				 * so the skb pointer must not be NULL.
1564				 */
1565				b43dbg(dev->wl, "TX status unexpected NULL skb "
1566				       "at slot %d (first=%d) on ring %d\n",
1567				       slot, firstused, ring->index);
1568				break;
1569			}
1570
1571			info = IEEE80211_SKB_CB(meta->skb);
1572
1573			/*
1574			 * Call back to inform the ieee80211 subsystem about
1575			 * the status of the transmission. When skipping over
1576			 * a missed TX status report, use a status structure
1577			 * filled with zeros to indicate that the frame was not
1578			 * sent (frame_count 0) and not acknowledged
1579			 */
1580			if (unlikely(skip))
1581				txstat = &fake;
1582			else
1583				txstat = status;
1584
1585			frame_succeed = b43_fill_txstatus_report(dev, info,
1586								 txstat);
1587#ifdef CONFIG_B43_DEBUG
1588			if (frame_succeed)
1589				ring->nr_succeed_tx_packets++;
1590			else
1591				ring->nr_failed_tx_packets++;
1592			ring->nr_total_packet_tries += status->frame_count;
1593#endif /* DEBUG */
1594			ieee80211_tx_status(dev->wl->hw, meta->skb);
1595
1596			/* skb will be freed by ieee80211_tx_status().
1597			 * Poison our pointer. */
1598			meta->skb = B43_DMA_PTR_POISON;
1599		} else {
1600			/* No need to call free_descriptor_buffer here, as
1601			 * this is only the txhdr, which is not allocated.
1602			 */
1603			if (unlikely(meta->skb)) {
1604				b43dbg(dev->wl, "TX status unexpected non-NULL skb "
1605				       "at slot %d (first=%d) on ring %d\n",
1606				       slot, firstused, ring->index);
1607				break;
1608			}
1609		}
1610
1611		/* Everything unmapped and free'd. So it's not used anymore. */
1612		ring->used_slots--;
1613
1614		if (meta->is_last_fragment && !skip) {
1615			/* This is the last scatter-gather
1616			 * fragment of the frame. We are done. */
1617			break;
1618		}
1619		slot = next_slot(ring, slot);
1620		if (skip > 0)
1621			--skip;
1622	}
1623	if (ring->stopped) {
1624		B43_WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME);
1625		ring->stopped = false;
1626	}
1627
1628	if (dev->wl->tx_queue_stopped[ring->queue_prio]) {
1629		dev->wl->tx_queue_stopped[ring->queue_prio] = 0;
1630	} else {
1631		/* If the driver queue is running wake the corresponding
1632		 * mac80211 queue. */
1633		ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
 
1634		if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
1635			b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
1636		}
1637	}
1638	/* Add work to the queue. */
1639	ieee80211_queue_work(dev->wl->hw, &dev->wl->tx_work);
1640}
1641
1642static void dma_rx(struct b43_dmaring *ring, int *slot)
1643{
1644	const struct b43_dma_ops *ops = ring->ops;
1645	struct b43_dmadesc_generic *desc;
1646	struct b43_dmadesc_meta *meta;
1647	struct b43_rxhdr_fw4 *rxhdr;
1648	struct sk_buff *skb;
1649	u16 len;
1650	int err;
1651	dma_addr_t dmaaddr;
1652
1653	desc = ops->idx2desc(ring, *slot, &meta);
1654
1655	sync_descbuffer_for_cpu(ring, meta->dmaaddr, ring->rx_buffersize);
1656	skb = meta->skb;
1657
1658	rxhdr = (struct b43_rxhdr_fw4 *)skb->data;
1659	len = le16_to_cpu(rxhdr->frame_len);
1660	if (len == 0) {
1661		int i = 0;
1662
1663		do {
1664			udelay(2);
1665			barrier();
1666			len = le16_to_cpu(rxhdr->frame_len);
1667		} while (len == 0 && i++ < 5);
1668		if (unlikely(len == 0)) {
1669			dmaaddr = meta->dmaaddr;
1670			goto drop_recycle_buffer;
1671		}
1672	}
1673	if (unlikely(b43_rx_buffer_is_poisoned(ring, skb))) {
1674		/* Something went wrong with the DMA.
1675		 * The device did not touch the buffer and did not overwrite the poison. */
1676		b43dbg(ring->dev->wl, "DMA RX: Dropping poisoned buffer.\n");
1677		dmaaddr = meta->dmaaddr;
1678		goto drop_recycle_buffer;
1679	}
1680	if (unlikely(len + ring->frameoffset > ring->rx_buffersize)) {
1681		/* The data did not fit into one descriptor buffer
1682		 * and is split over multiple buffers.
1683		 * This should never happen, as we try to allocate buffers
1684		 * big enough. So simply ignore this packet.
1685		 */
1686		int cnt = 0;
1687		s32 tmp = len;
1688
1689		while (1) {
1690			desc = ops->idx2desc(ring, *slot, &meta);
1691			/* recycle the descriptor buffer. */
1692			b43_poison_rx_buffer(ring, meta->skb);
1693			sync_descbuffer_for_device(ring, meta->dmaaddr,
1694						   ring->rx_buffersize);
1695			*slot = next_slot(ring, *slot);
1696			cnt++;
1697			tmp -= ring->rx_buffersize;
1698			if (tmp <= 0)
1699				break;
1700		}
1701		b43err(ring->dev->wl, "DMA RX buffer too small "
1702		       "(len: %u, buffer: %u, nr-dropped: %d)\n",
1703		       len, ring->rx_buffersize, cnt);
1704		goto drop;
1705	}
1706
1707	dmaaddr = meta->dmaaddr;
1708	err = setup_rx_descbuffer(ring, desc, meta, GFP_ATOMIC);
1709	if (unlikely(err)) {
1710		b43dbg(ring->dev->wl, "DMA RX: setup_rx_descbuffer() failed\n");
1711		goto drop_recycle_buffer;
1712	}
1713
1714	unmap_descbuffer(ring, dmaaddr, ring->rx_buffersize, 0);
1715	skb_put(skb, len + ring->frameoffset);
1716	skb_pull(skb, ring->frameoffset);
1717
1718	b43_rx(ring->dev, skb, rxhdr);
1719drop:
1720	return;
1721
1722drop_recycle_buffer:
1723	/* Poison and recycle the RX buffer. */
1724	b43_poison_rx_buffer(ring, skb);
1725	sync_descbuffer_for_device(ring, dmaaddr, ring->rx_buffersize);
1726}
1727
1728void b43_dma_handle_rx_overflow(struct b43_dmaring *ring)
1729{
1730	int current_slot, previous_slot;
1731
1732	B43_WARN_ON(ring->tx);
1733
1734	/* Device has filled all buffers, drop all packets and let TCP
1735	 * decrease speed.
1736	 * Decrement RX index by one will let the device to see all slots
1737	 * as free again
1738	 */
1739	/*
1740	*TODO: How to increase rx_drop in mac80211?
1741	*/
1742	current_slot = ring->ops->get_current_rxslot(ring);
1743	previous_slot = prev_slot(ring, current_slot);
1744	ring->ops->set_current_rxslot(ring, previous_slot);
1745}
1746
1747void b43_dma_rx(struct b43_dmaring *ring)
1748{
1749	const struct b43_dma_ops *ops = ring->ops;
1750	int slot, current_slot;
1751	int used_slots = 0;
1752
1753	B43_WARN_ON(ring->tx);
1754	current_slot = ops->get_current_rxslot(ring);
1755	B43_WARN_ON(!(current_slot >= 0 && current_slot < ring->nr_slots));
1756
1757	slot = ring->current_slot;
1758	for (; slot != current_slot; slot = next_slot(ring, slot)) {
1759		dma_rx(ring, &slot);
1760		update_max_used_slots(ring, ++used_slots);
1761	}
1762	wmb();
1763	ops->set_current_rxslot(ring, slot);
1764	ring->current_slot = slot;
1765}
1766
1767static void b43_dma_tx_suspend_ring(struct b43_dmaring *ring)
1768{
1769	B43_WARN_ON(!ring->tx);
1770	ring->ops->tx_suspend(ring);
1771}
1772
1773static void b43_dma_tx_resume_ring(struct b43_dmaring *ring)
1774{
1775	B43_WARN_ON(!ring->tx);
1776	ring->ops->tx_resume(ring);
1777}
1778
1779void b43_dma_tx_suspend(struct b43_wldev *dev)
1780{
1781	b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
1782	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BK);
1783	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_BE);
1784	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VI);
1785	b43_dma_tx_suspend_ring(dev->dma.tx_ring_AC_VO);
1786	b43_dma_tx_suspend_ring(dev->dma.tx_ring_mcast);
1787}
1788
1789void b43_dma_tx_resume(struct b43_wldev *dev)
1790{
1791	b43_dma_tx_resume_ring(dev->dma.tx_ring_mcast);
1792	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VO);
1793	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_VI);
1794	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BE);
1795	b43_dma_tx_resume_ring(dev->dma.tx_ring_AC_BK);
1796	b43_power_saving_ctl_bits(dev, 0);
1797}
1798
1799static void direct_fifo_rx(struct b43_wldev *dev, enum b43_dmatype type,
1800			   u16 mmio_base, bool enable)
1801{
1802	u32 ctl;
1803
1804	if (type == B43_DMA_64BIT) {
1805		ctl = b43_read32(dev, mmio_base + B43_DMA64_RXCTL);
1806		ctl &= ~B43_DMA64_RXDIRECTFIFO;
1807		if (enable)
1808			ctl |= B43_DMA64_RXDIRECTFIFO;
1809		b43_write32(dev, mmio_base + B43_DMA64_RXCTL, ctl);
1810	} else {
1811		ctl = b43_read32(dev, mmio_base + B43_DMA32_RXCTL);
1812		ctl &= ~B43_DMA32_RXDIRECTFIFO;
1813		if (enable)
1814			ctl |= B43_DMA32_RXDIRECTFIFO;
1815		b43_write32(dev, mmio_base + B43_DMA32_RXCTL, ctl);
1816	}
1817}
1818
1819/* Enable/Disable Direct FIFO Receive Mode (PIO) on a RX engine.
1820 * This is called from PIO code, so DMA structures are not available. */
1821void b43_dma_direct_fifo_rx(struct b43_wldev *dev,
1822			    unsigned int engine_index, bool enable)
1823{
1824	enum b43_dmatype type;
1825	u16 mmio_base;
1826
1827	type = dma_mask_to_engine_type(supported_dma_mask(dev));
1828
1829	mmio_base = b43_dmacontroller_base(type, engine_index);
1830	direct_fifo_rx(dev, type, mmio_base, enable);
1831}