drivers/firewire/ohci.c

   1 /*
   2  * Driver for OHCI 1394 controllers
   3  *
   4  * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include <linux/bitops.h>
  22 #include <linux/bug.h>
  23 #include <linux/compiler.h>
  24 #include <linux/delay.h>
  25 #include <linux/device.h>
  26 #include <linux/dma-mapping.h>
  27 #include <linux/firewire.h>
  28 #include <linux/firewire-constants.h>
  29 #include <linux/init.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/io.h>
  32 #include <linux/kernel.h>
  33 #include <linux/list.h>
  34 #include <linux/mm.h>
  35 #include <linux/module.h>
  36 #include <linux/moduleparam.h>
  37 #include <linux/mutex.h>
  38 #include <linux/pci.h>
  39 #include <linux/pci_ids.h>
  40 #include <linux/slab.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/string.h>
  43 #include <linux/time.h>
  44 #include <linux/vmalloc.h>
  45
  46 #include <asm/byteorder.h>
  47 #include <asm/page.h>
  48 #include <asm/system.h>
  49
  50 #ifdef CONFIG_PPC_PMAC
  51 #include <asm/pmac_feature.h>
  52 #endif
  53
  54 #include "core.h"
  55 #include "ohci.h"
  56
  57 #define DESCRIPTOR_OUTPUT_MORE          0
  58 #define DESCRIPTOR_OUTPUT_LAST          (1 << 12)
  59 #define DESCRIPTOR_INPUT_MORE           (2 << 12)
  60 #define DESCRIPTOR_INPUT_LAST           (3 << 12)
  61 #define DESCRIPTOR_STATUS               (1 << 11)
  62 #define DESCRIPTOR_KEY_IMMEDIATE        (2 << 8)
  63 #define DESCRIPTOR_PING                 (1 << 7)
  64 #define DESCRIPTOR_YY                   (1 << 6)
  65 #define DESCRIPTOR_NO_IRQ               (0 << 4)
  66 #define DESCRIPTOR_IRQ_ERROR            (1 << 4)
  67 #define DESCRIPTOR_IRQ_ALWAYS           (3 << 4)
  68 #define DESCRIPTOR_BRANCH_ALWAYS        (3 << 2)
  69 #define DESCRIPTOR_WAIT                 (3 << 0)
  70
  71 struct descriptor {
  72         __le16 req_count;
  73         __le16 control;
  74         __le32 data_address;
  75         __le32 branch_address;
  76         __le16 res_count;
  77         __le16 transfer_status;
  78 } __attribute__((aligned(16)));
  79
  80 #define CONTROL_SET(regs)       (regs)
  81 #define CONTROL_CLEAR(regs)     ((regs) + 4)
  82 #define COMMAND_PTR(regs)       ((regs) + 12)
  83 #define CONTEXT_MATCH(regs)     ((regs) + 16)
  84
  85 #define AR_BUFFER_SIZE  (32*1024)
  86 #define AR_BUFFERS_MIN  DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
  87 /* we need at least two pages for proper list management */
  88 #define AR_BUFFERS      (AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)
  89
  90 #define MAX_ASYNC_PAYLOAD       4096
  91 #define MAX_AR_PACKET_SIZE      (16 + MAX_ASYNC_PAYLOAD + 4)
  92 #define AR_WRAPAROUND_PAGES     DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)
  93
  94 struct ar_context {
  95         struct fw_ohci *ohci;
  96         struct page *pages[AR_BUFFERS];
  97         void *buffer;
  98         struct descriptor *descriptors;
  99         dma_addr_t descriptors_bus;
 100         void *pointer;
 101         unsigned int last_buffer_index;
 102         u32 regs;
 103         struct tasklet_struct tasklet;
 104 };
 105
 106 struct context;
 107
 108 typedef int (*descriptor_callback_t)(struct context *ctx,
 109                                      struct descriptor *d,
 110                                      struct descriptor *last);
 111
 112 /*
 113  * A buffer that contains a block of DMA-able coherent memory used for
 114  * storing a portion of a DMA descriptor program.
 115  */
 116 struct descriptor_buffer {
 117         struct list_head list;
 118         dma_addr_t buffer_bus;
 119         size_t buffer_size;
 120         size_t used;
 121         struct descriptor buffer[0];
 122 };
 123
 124 struct context {
 125         struct fw_ohci *ohci;
 126         u32 regs;
 127         int total_allocation;
 128         bool running;
 129         bool flushing;
 130
 131         /*
 132          * List of page-sized buffers for storing DMA descriptors.
 133          * Head of list contains buffers in use and tail of list contains
 134          * free buffers.
 135          */
 136         struct list_head buffer_list;
 137
 138         /*
 139          * Pointer to a buffer inside buffer_list that contains the tail
 140          * end of the current DMA program.
 141          */
 142         struct descriptor_buffer *buffer_tail;
 143
 144         /*
 145          * The descriptor containing the branch address of the first
 146          * descriptor that has not yet been filled by the device.
 147          */
 148         struct descriptor *last;
 149
 150         /*
 151          * The last descriptor in the DMA program.  It contains the branch
 152          * address that must be updated upon appending a new descriptor.
 153          */
 154         struct descriptor *prev;
 155
 156         descriptor_callback_t callback;
 157
 158         struct tasklet_struct tasklet;
 159 };
 160
 161 #define IT_HEADER_SY(v)          ((v) <<  0)
 162 #define IT_HEADER_TCODE(v)       ((v) <<  4)
 163 #define IT_HEADER_CHANNEL(v)     ((v) <<  8)
 164 #define IT_HEADER_TAG(v)         ((v) << 14)
 165 #define IT_HEADER_SPEED(v)       ((v) << 16)
 166 #define IT_HEADER_DATA_LENGTH(v) ((v) << 16)
 167
 168 struct iso_context {
 169         struct fw_iso_context base;
 170         struct context context;
 171         int excess_bytes;
 172         void *header;
 173         size_t header_length;
 174
 175         u8 sync;
 176         u8 tags;
 177 };
 178
 179 #define CONFIG_ROM_SIZE 1024
 180
 181 struct fw_ohci {
 182         struct fw_card card;
 183
 184         __iomem char *registers;
 185         int node_id;
 186         int generation;
 187         int request_generation; /* for timestamping incoming requests */
 188         unsigned quirks;
 189         unsigned int pri_req_max;
 190         u32 bus_time;
 191         bool is_root;
 192         bool csr_state_setclear_abdicate;
 193         int n_ir;
 194         int n_it;
 195         /*
 196          * Spinlock for accessing fw_ohci data.  Never call out of
 197          * this driver with this lock held.
 198          */
 199         spinlock_t lock;
 200
 201         struct mutex phy_reg_mutex;
 202
 203         void *misc_buffer;
 204         dma_addr_t misc_buffer_bus;
 205
 206         struct ar_context ar_request_ctx;
 207         struct ar_context ar_response_ctx;
 208         struct context at_request_ctx;
 209         struct context at_response_ctx;
 210
 211         u32 it_context_support;
 212         u32 it_context_mask;     /* unoccupied IT contexts */
 213         struct iso_context *it_context_list;
 214         u64 ir_context_channels; /* unoccupied channels */
 215         u32 ir_context_support;
 216         u32 ir_context_mask;     /* unoccupied IR contexts */
 217         struct iso_context *ir_context_list;
 218         u64 mc_channels; /* channels in use by the multichannel IR context */
 219         bool mc_allocated;
 220
 221         __be32    *config_rom;
 222         dma_addr_t config_rom_bus;
 223         __be32    *next_config_rom;
 224         dma_addr_t next_config_rom_bus;
 225         __be32     next_header;
 226
 227         __le32    *self_id_cpu;
 228         dma_addr_t self_id_bus;
 229         struct tasklet_struct bus_reset_tasklet;
 230
 231         u32 self_id_buffer[512];
 232 };
 233
 234 static inline struct fw_ohci *fw_ohci(struct fw_card *card)
 235 {
 236         return container_of(card, struct fw_ohci, card);
 237 }
 238
 239 #define IT_CONTEXT_CYCLE_MATCH_ENABLE   0x80000000
 240 #define IR_CONTEXT_BUFFER_FILL          0x80000000
 241 #define IR_CONTEXT_ISOCH_HEADER         0x40000000
 242 #define IR_CONTEXT_CYCLE_MATCH_ENABLE   0x20000000
 243 #define IR_CONTEXT_MULTI_CHANNEL_MODE   0x10000000
 244 #define IR_CONTEXT_DUAL_BUFFER_MODE     0x08000000
 245
 246 #define CONTEXT_RUN     0x8000
 247 #define CONTEXT_WAKE    0x1000
 248 #define CONTEXT_DEAD    0x0800
 249 #define CONTEXT_ACTIVE  0x0400
 250
 251 #define OHCI1394_MAX_AT_REQ_RETRIES     0xf
 252 #define OHCI1394_MAX_AT_RESP_RETRIES    0x2
 253 #define OHCI1394_MAX_PHYS_RESP_RETRIES  0x8
 254
 255 #define OHCI1394_REGISTER_SIZE          0x800
 256 #define OHCI1394_PCI_HCI_Control        0x40
 257 #define SELF_ID_BUF_SIZE                0x800
 258 #define OHCI_TCODE_PHY_PACKET           0x0e
 259 #define OHCI_VERSION_1_1                0x010010
 260
 261 static char ohci_driver_name[] = KBUILD_MODNAME;
 262
 263 #define PCI_DEVICE_ID_AGERE_FW643       0x5901
 264 #define PCI_DEVICE_ID_JMICRON_JMB38X_FW 0x2380
 265 #define PCI_DEVICE_ID_TI_TSB12LV22      0x8009
 266 #define PCI_VENDOR_ID_PINNACLE_SYSTEMS  0x11bd
 267
 268 #define QUIRK_CYCLE_TIMER               1
 269 #define QUIRK_RESET_PACKET              2
 270 #define QUIRK_BE_HEADERS                4
 271 #define QUIRK_NO_1394A                  8
 272 #define QUIRK_NO_MSI                    16
 273
 274 /* In case of multiple matches in ohci_quirks[], only the first one is used. */
 275 static const struct {
 276         unsigned short vendor, device, revision, flags;
 277 } ohci_quirks[] = {
 278         {PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
 279                 QUIRK_CYCLE_TIMER},
 280
 281         {PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
 282                 QUIRK_BE_HEADERS},
 283
 284         {PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
 285                 QUIRK_NO_MSI},
 286
 287         {PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
 288                 QUIRK_NO_MSI},
 289
 290         {PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
 291                 QUIRK_CYCLE_TIMER},
 292
 293         {PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
 294                 QUIRK_CYCLE_TIMER},
 295
 296         {PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
 297                 QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},
 298
 299         {PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
 300                 QUIRK_RESET_PACKET},
 301
 302         {PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
 303                 QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
 304 };
 305
 306 /* This overrides anything that was found in ohci_quirks[]. */
 307 static int param_quirks;
 308 module_param_named(quirks, param_quirks, int, 0644);
 309 MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
 310         ", nonatomic cycle timer = "    __stringify(QUIRK_CYCLE_TIMER)
 311         ", reset packet generation = "  __stringify(QUIRK_RESET_PACKET)
 312         ", AR/selfID endianess = "      __stringify(QUIRK_BE_HEADERS)
 313         ", no 1394a enhancements = "    __stringify(QUIRK_NO_1394A)
 314         ", disable MSI = "              __stringify(QUIRK_NO_MSI)
 315         ")");
 316
 317 #define OHCI_PARAM_DEBUG_AT_AR          1
 318 #define OHCI_PARAM_DEBUG_SELFIDS        2
 319 #define OHCI_PARAM_DEBUG_IRQS           4
 320 #define OHCI_PARAM_DEBUG_BUSRESETS      8 /* only effective before chip init */
 321
 322 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
 323
 324 static int param_debug;
 325 module_param_named(debug, param_debug, int, 0644);
 326 MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
 327         ", AT/AR events = "     __stringify(OHCI_PARAM_DEBUG_AT_AR)
 328         ", self-IDs = "         __stringify(OHCI_PARAM_DEBUG_SELFIDS)
 329         ", IRQs = "             __stringify(OHCI_PARAM_DEBUG_IRQS)
 330         ", busReset events = "  __stringify(OHCI_PARAM_DEBUG_BUSRESETS)
 331         ", or a combination, or all = -1)");
 332
 333 static void log_irqs(u32 evt)
 334 {
 335         if (likely(!(param_debug &
 336                         (OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
 337                 return;
 338
 339         if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
 340             !(evt & OHCI1394_busReset))
 341                 return;
 342
 343         fw_notify("IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
 344             evt & OHCI1394_selfIDComplete       ? " selfID"             : "",
 345             evt & OHCI1394_RQPkt                ? " AR_req"             : "",
 346             evt & OHCI1394_RSPkt                ? " AR_resp"            : "",
 347             evt & OHCI1394_reqTxComplete        ? " AT_req"             : "",
 348             evt & OHCI1394_respTxComplete       ? " AT_resp"            : "",
 349             evt & OHCI1394_isochRx              ? " IR"                 : "",
 350             evt & OHCI1394_isochTx              ? " IT"                 : "",
 351             evt & OHCI1394_postedWriteErr       ? " postedWriteErr"     : "",
 352             evt & OHCI1394_cycleTooLong         ? " cycleTooLong"       : "",
 353             evt & OHCI1394_cycle64Seconds       ? " cycle64Seconds"     : "",
 354             evt & OHCI1394_cycleInconsistent    ? " cycleInconsistent"  : "",
 355             evt & OHCI1394_regAccessFail        ? " regAccessFail"      : "",
 356             evt & OHCI1394_unrecoverableError   ? " unrecoverableError" : "",
 357             evt & OHCI1394_busReset             ? " busReset"           : "",
 358             evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
 359                     OHCI1394_RSPkt | OHCI1394_reqTxComplete |
 360                     OHCI1394_respTxComplete | OHCI1394_isochRx |
 361                     OHCI1394_isochTx | OHCI1394_postedWriteErr |
 362                     OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
 363                     OHCI1394_cycleInconsistent |
 364                     OHCI1394_regAccessFail | OHCI1394_busReset)
 365                                                 ? " ?"                  : "");
 366 }
 367
 368 static const char *speed[] = {
 369         [0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
 370 };
 371 static const char *power[] = {
 372         [0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
 373         [4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
 374 };
 375 static const char port[] = { '.', '-', 'p', 'c', };
 376
 377 static char _p(u32 *s, int shift)
 378 {
 379         return port[*s >> shift & 3];
 380 }
 381
 382 static void log_selfids(int node_id, int generation, int self_id_count, u32 *s)
 383 {
 384         if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
 385                 return;
 386
 387         fw_notify("%d selfIDs, generation %d, local node ID %04x\n",
 388                   self_id_count, generation, node_id);
 389
 390         for (; self_id_count--; ++s)
 391                 if ((*s & 1 << 23) == 0)
 392                         fw_notify("selfID 0: %08x, phy %d [%c%c%c] "
 393                             "%s gc=%d %s %s%s%s\n",
 394                             *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
 395                             speed[*s >> 14 & 3], *s >> 16 & 63,
 396                             power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
 397                             *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
 398                 else
 399                         fw_notify("selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
 400                             *s, *s >> 24 & 63,
 401                             _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
 402                             _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
 403 }
 404
 405 static const char *evts[] = {
 406         [0x00] = "evt_no_status",       [0x01] = "-reserved-",
 407         [0x02] = "evt_long_packet",     [0x03] = "evt_missing_ack",
 408         [0x04] = "evt_underrun",        [0x05] = "evt_overrun",
 409         [0x06] = "evt_descriptor_read", [0x07] = "evt_data_read",
 410         [0x08] = "evt_data_write",      [0x09] = "evt_bus_reset",
 411         [0x0a] = "evt_timeout",         [0x0b] = "evt_tcode_err",
 412         [0x0c] = "-reserved-",          [0x0d] = "-reserved-",
 413         [0x0e] = "evt_unknown",         [0x0f] = "evt_flushed",
 414         [0x10] = "-reserved-",          [0x11] = "ack_complete",
 415         [0x12] = "ack_pending ",        [0x13] = "-reserved-",
 416         [0x14] = "ack_busy_X",          [0x15] = "ack_busy_A",
 417         [0x16] = "ack_busy_B",          [0x17] = "-reserved-",
 418         [0x18] = "-reserved-",          [0x19] = "-reserved-",
 419         [0x1a] = "-reserved-",          [0x1b] = "ack_tardy",
 420         [0x1c] = "-reserved-",          [0x1d] = "ack_data_error",
 421         [0x1e] = "ack_type_error",      [0x1f] = "-reserved-",
 422         [0x20] = "pending/cancelled",
 423 };
 424 static const char *tcodes[] = {
 425         [0x0] = "QW req",               [0x1] = "BW req",
 426         [0x2] = "W resp",               [0x3] = "-reserved-",
 427         [0x4] = "QR req",               [0x5] = "BR req",
 428         [0x6] = "QR resp",              [0x7] = "BR resp",
 429         [0x8] = "cycle start",          [0x9] = "Lk req",
 430         [0xa] = "async stream packet",  [0xb] = "Lk resp",
 431         [0xc] = "-reserved-",           [0xd] = "-reserved-",
 432         [0xe] = "link internal",        [0xf] = "-reserved-",
 433 };
 434
 435 static void log_ar_at_event(char dir, int speed, u32 *header, int evt)
 436 {
 437         int tcode = header[0] >> 4 & 0xf;
 438         char specific[12];
 439
 440         if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
 441                 return;
 442
 443         if (unlikely(evt >= ARRAY_SIZE(evts)))
 444                         evt = 0x1f;
 445
 446         if (evt == OHCI1394_evt_bus_reset) {
 447                 fw_notify("A%c evt_bus_reset, generation %d\n",
 448                     dir, (header[2] >> 16) & 0xff);
 449                 return;
 450         }
 451
 452         switch (tcode) {
 453         case 0x0: case 0x6: case 0x8:
 454                 snprintf(specific, sizeof(specific), " = %08x",
 455                          be32_to_cpu((__force __be32)header[3]));
 456                 break;
 457         case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
 458                 snprintf(specific, sizeof(specific), " %x,%x",
 459                          header[3] >> 16, header[3] & 0xffff);
 460                 break;
 461         default:
 462                 specific[0] = '\0';
 463         }
 464
 465         switch (tcode) {
 466         case 0xa:
 467                 fw_notify("A%c %s, %s\n", dir, evts[evt], tcodes[tcode]);
 468                 break;
 469         case 0xe:
 470                 fw_notify("A%c %s, PHY %08x %08x\n",
 471                           dir, evts[evt], header[1], header[2]);
 472                 break;
 473         case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
 474                 fw_notify("A%c spd %x tl %02x, "
 475                     "%04x -> %04x, %s, "
 476                     "%s, %04x%08x%s\n",
 477                     dir, speed, header[0] >> 10 & 0x3f,
 478                     header[1] >> 16, header[0] >> 16, evts[evt],
 479                     tcodes[tcode], header[1] & 0xffff, header[2], specific);
 480                 break;
 481         default:
 482                 fw_notify("A%c spd %x tl %02x, "
 483                     "%04x -> %04x, %s, "
 484                     "%s%s\n",
 485                     dir, speed, header[0] >> 10 & 0x3f,
 486                     header[1] >> 16, header[0] >> 16, evts[evt],
 487                     tcodes[tcode], specific);
 488         }
 489 }
 490
 491 #else
 492
 493 #define param_debug 0
 494 static inline void log_irqs(u32 evt) {}
 495 static inline void log_selfids(int node_id, int generation, int self_id_count, u32 *s) {}
 496 static inline void log_ar_at_event(char dir, int speed, u32 *header, int evt) {}
 497
 498 #endif /* CONFIG_FIREWIRE_OHCI_DEBUG */
 499
 500 static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
 501 {
 502         writel(data, ohci->registers + offset);
 503 }
 504
 505 static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
 506 {
 507         return readl(ohci->registers + offset);
 508 }
 509
 510 static inline void flush_writes(const struct fw_ohci *ohci)
 511 {
 512         /* Do a dummy read to flush writes. */
 513         reg_read(ohci, OHCI1394_Version);
 514 }
 515
 516 /*
 517  * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
 518  * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
 519  * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
 520  * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
 521  */
 522 static int read_phy_reg(struct fw_ohci *ohci, int addr)
 523 {
 524         u32 val;
 525         int i;
 526
 527         reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
 528         for (i = 0; i < 3 + 100; i++) {
 529                 val = reg_read(ohci, OHCI1394_PhyControl);
 530                 if (!~val)
 531                         return -ENODEV; /* Card was ejected. */
 532
 533                 if (val & OHCI1394_PhyControl_ReadDone)
 534                         return OHCI1394_PhyControl_ReadData(val);
 535
 536                 /*
 537                  * Try a few times without waiting.  Sleeping is necessary
 538                  * only when the link/PHY interface is busy.
 539                  */
 540                 if (i >= 3)
 541                         msleep(1);
 542         }
 543         fw_error("failed to read phy reg\n");
 544
 545         return -EBUSY;
 546 }
 547
 548 static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
 549 {
 550         int i;
 551
 552         reg_write(ohci, OHCI1394_PhyControl,
 553                   OHCI1394_PhyControl_Write(addr, val));
 554         for (i = 0; i < 3 + 100; i++) {
 555                 val = reg_read(ohci, OHCI1394_PhyControl);
 556                 if (!~val)
 557                         return -ENODEV; /* Card was ejected. */
 558
 559                 if (!(val & OHCI1394_PhyControl_WritePending))
 560                         return 0;
 561
 562                 if (i >= 3)
 563                         msleep(1);
 564         }
 565         fw_error("failed to write phy reg\n");
 566
 567         return -EBUSY;
 568 }
 569
 570 static int update_phy_reg(struct fw_ohci *ohci, int addr,
 571                           int clear_bits, int set_bits)
 572 {
 573         int ret = read_phy_reg(ohci, addr);
 574         if (ret < 0)
 575                 return ret;
 576
 577         /*
 578          * The interrupt status bits are cleared by writing a one bit.
 579          * Avoid clearing them unless explicitly requested in set_bits.
 580          */
 581         if (addr == 5)
 582                 clear_bits |= PHY_INT_STATUS_BITS;
 583
 584         return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
 585 }
 586
 587 static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
 588 {
 589         int ret;
 590
 591         ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
 592         if (ret < 0)
 593                 return ret;
 594
 595         return read_phy_reg(ohci, addr);
 596 }
 597
 598 static int ohci_read_phy_reg(struct fw_card *card, int addr)
 599 {
 600         struct fw_ohci *ohci = fw_ohci(card);
 601         int ret;
 602
 603         mutex_lock(&ohci->phy_reg_mutex);
 604         ret = read_phy_reg(ohci, addr);
 605         mutex_unlock(&ohci->phy_reg_mutex);
 606
 607         return ret;
 608 }
 609
 610 static int ohci_update_phy_reg(struct fw_card *card, int addr,
 611                                int clear_bits, int set_bits)
 612 {
 613         struct fw_ohci *ohci = fw_ohci(card);
 614         int ret;
 615
 616         mutex_lock(&ohci->phy_reg_mutex);
 617         ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
 618         mutex_unlock(&ohci->phy_reg_mutex);
 619
 620         return ret;
 621 }
 622
 623 static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
 624 {
 625         return page_private(ctx->pages[i]);
 626 }
 627
 628 static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
 629 {
 630         struct descriptor *d;
 631
 632         d = &ctx->descriptors[index];
 633         d->branch_address  &= cpu_to_le32(~0xf);
 634         d->res_count       =  cpu_to_le16(PAGE_SIZE);
 635         d->transfer_status =  0;
 636
 637         wmb(); /* finish init of new descriptors before branch_address update */
 638         d = &ctx->descriptors[ctx->last_buffer_index];
 639         d->branch_address  |= cpu_to_le32(1);
 640
 641         ctx->last_buffer_index = index;
 642
 643         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
 644 }
 645
 646 static void ar_context_release(struct ar_context *ctx)
 647 {
 648         unsigned int i;
 649
 650         if (ctx->buffer)
 651                 vm_unmap_ram(ctx->buffer, AR_BUFFERS + AR_WRAPAROUND_PAGES);
 652
 653         for (i = 0; i < AR_BUFFERS; i++)
 654                 if (ctx->pages[i]) {
 655                         dma_unmap_page(ctx->ohci->card.device,
 656                                        ar_buffer_bus(ctx, i),
 657                                        PAGE_SIZE, DMA_FROM_DEVICE);
 658                         __free_page(ctx->pages[i]);
 659                 }
 660 }
 661
 662 static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
 663 {
 664         if (reg_read(ctx->ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
 665                 reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
 666                 flush_writes(ctx->ohci);
 667
 668                 fw_error("AR error: %s; DMA stopped\n", error_msg);
 669         }
 670         /* FIXME: restart? */
 671 }
 672
 673 static inline unsigned int ar_next_buffer_index(unsigned int index)
 674 {
 675         return (index + 1) % AR_BUFFERS;
 676 }
 677
 678 static inline unsigned int ar_prev_buffer_index(unsigned int index)
 679 {
 680         return (index - 1 + AR_BUFFERS) % AR_BUFFERS;
 681 }
 682
 683 static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
 684 {
 685         return ar_next_buffer_index(ctx->last_buffer_index);
 686 }
 687
 688 /*
 689  * We search for the buffer that contains the last AR packet DMA data written
 690  * by the controller.
 691  */
 692 static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
 693                                                  unsigned int *buffer_offset)
 694 {
 695         unsigned int i, next_i, last = ctx->last_buffer_index;
 696         __le16 res_count, next_res_count;
 697
 698         i = ar_first_buffer_index(ctx);
 699         res_count = ACCESS_ONCE(ctx->descriptors[i].res_count);
 700
 701         /* A buffer that is not yet completely filled must be the last one. */
 702         while (i != last && res_count == 0) {
 703
 704                 /* Peek at the next descriptor. */
 705                 next_i = ar_next_buffer_index(i);
 706                 rmb(); /* read descriptors in order */
 707                 next_res_count = ACCESS_ONCE(
 708                                 ctx->descriptors[next_i].res_count);
 709                 /*
 710                  * If the next descriptor is still empty, we must stop at this
 711                  * descriptor.
 712                  */
 713                 if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
 714                         /*
 715                          * The exception is when the DMA data for one packet is
 716                          * split over three buffers; in this case, the middle
 717                          * buffer's descriptor might be never updated by the
 718                          * controller and look still empty, and we have to peek
 719                          * at the third one.
 720                          */
 721                         if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
 722                                 next_i = ar_next_buffer_index(next_i);
 723                                 rmb();
 724                                 next_res_count = ACCESS_ONCE(
 725                                         ctx->descriptors[next_i].res_count);
 726                                 if (next_res_count != cpu_to_le16(PAGE_SIZE))
 727                                         goto next_buffer_is_active;
 728                         }
 729
 730                         break;
 731                 }
 732
 733 next_buffer_is_active:
 734                 i = next_i;
 735                 res_count = next_res_count;
 736         }
 737
 738         rmb(); /* read res_count before the DMA data */
 739
 740         *buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
 741         if (*buffer_offset > PAGE_SIZE) {
 742                 *buffer_offset = 0;
 743                 ar_context_abort(ctx, "corrupted descriptor");
 744         }
 745
 746         return i;
 747 }
 748
 749 static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
 750                                     unsigned int end_buffer_index,
 751                                     unsigned int end_buffer_offset)
 752 {
 753         unsigned int i;
 754
 755         i = ar_first_buffer_index(ctx);
 756         while (i != end_buffer_index) {
 757                 dma_sync_single_for_cpu(ctx->ohci->card.device,
 758                                         ar_buffer_bus(ctx, i),
 759                                         PAGE_SIZE, DMA_FROM_DEVICE);
 760                 i = ar_next_buffer_index(i);
 761         }
 762         if (end_buffer_offset > 0)
 763                 dma_sync_single_for_cpu(ctx->ohci->card.device,
 764                                         ar_buffer_bus(ctx, i),
 765                                         end_buffer_offset, DMA_FROM_DEVICE);
 766 }
 767
 768 #if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
 769 #define cond_le32_to_cpu(v) \
 770         (ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
 771 #else
 772 #define cond_le32_to_cpu(v) le32_to_cpu(v)
 773 #endif
 774
 775 static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
 776 {
 777         struct fw_ohci *ohci = ctx->ohci;
 778         struct fw_packet p;
 779         u32 status, length, tcode;
 780         int evt;
 781
 782         p.header[0] = cond_le32_to_cpu(buffer[0]);
 783         p.header[1] = cond_le32_to_cpu(buffer[1]);
 784         p.header[2] = cond_le32_to_cpu(buffer[2]);
 785
 786         tcode = (p.header[0] >> 4) & 0x0f;
 787         switch (tcode) {
 788         case TCODE_WRITE_QUADLET_REQUEST:
 789         case TCODE_READ_QUADLET_RESPONSE:
 790                 p.header[3] = (__force __u32) buffer[3];
 791                 p.header_length = 16;
 792                 p.payload_length = 0;
 793                 break;
 794
 795         case TCODE_READ_BLOCK_REQUEST :
 796                 p.header[3] = cond_le32_to_cpu(buffer[3]);
 797                 p.header_length = 16;
 798                 p.payload_length = 0;
 799                 break;
 800
 801         case TCODE_WRITE_BLOCK_REQUEST:
 802         case TCODE_READ_BLOCK_RESPONSE:
 803         case TCODE_LOCK_REQUEST:
 804         case TCODE_LOCK_RESPONSE:
 805                 p.header[3] = cond_le32_to_cpu(buffer[3]);
 806                 p.header_length = 16;
 807                 p.payload_length = p.header[3] >> 16;
 808                 if (p.payload_length > MAX_ASYNC_PAYLOAD) {
 809                         ar_context_abort(ctx, "invalid packet length");
 810                         return NULL;
 811                 }
 812                 break;
 813
 814         case TCODE_WRITE_RESPONSE:
 815         case TCODE_READ_QUADLET_REQUEST:
 816         case OHCI_TCODE_PHY_PACKET:
 817                 p.header_length = 12;
 818                 p.payload_length = 0;
 819                 break;
 820
 821         default:
 822                 ar_context_abort(ctx, "invalid tcode");
 823                 return NULL;
 824         }
 825
 826         p.payload = (void *) buffer + p.header_length;
 827
 828         /* FIXME: What to do about evt_* errors? */
 829         length = (p.header_length + p.payload_length + 3) / 4;
 830         status = cond_le32_to_cpu(buffer[length]);
 831         evt    = (status >> 16) & 0x1f;
 832
 833         p.ack        = evt - 16;
 834         p.speed      = (status >> 21) & 0x7;
 835         p.timestamp  = status & 0xffff;
 836         p.generation = ohci->request_generation;
 837
 838         log_ar_at_event('R', p.speed, p.header, evt);
 839
 840         /*
 841          * Several controllers, notably from NEC and VIA, forget to
 842          * write ack_complete status at PHY packet reception.
 843          */
 844         if (evt == OHCI1394_evt_no_status &&
 845             (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
 846                 p.ack = ACK_COMPLETE;
 847
 848         /*
 849          * The OHCI bus reset handler synthesizes a PHY packet with
 850          * the new generation number when a bus reset happens (see
 851          * section 8.4.2.3).  This helps us determine when a request
 852          * was received and make sure we send the response in the same
 853          * generation.  We only need this for requests; for responses
 854          * we use the unique tlabel for finding the matching
 855          * request.
 856          *
 857          * Alas some chips sometimes emit bus reset packets with a
 858          * wrong generation.  We set the correct generation for these
 859          * at a slightly incorrect time (in bus_reset_tasklet).
 860          */
 861         if (evt == OHCI1394_evt_bus_reset) {
 862                 if (!(ohci->quirks & QUIRK_RESET_PACKET))
 863                         ohci->request_generation = (p.header[2] >> 16) & 0xff;
 864         } else if (ctx == &ohci->ar_request_ctx) {
 865                 fw_core_handle_request(&ohci->card, &p);
 866         } else {
 867                 fw_core_handle_response(&ohci->card, &p);
 868         }
 869
 870         return buffer + length + 1;
 871 }
 872
 873 static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
 874 {
 875         void *next;
 876
 877         while (p < end) {
 878                 next = handle_ar_packet(ctx, p);
 879                 if (!next)
 880                         return p;
 881                 p = next;
 882         }
 883
 884         return p;
 885 }
 886
 887 static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
 888 {
 889         unsigned int i;
 890
 891         i = ar_first_buffer_index(ctx);
 892         while (i != end_buffer) {
 893                 dma_sync_single_for_device(ctx->ohci->card.device,
 894                                            ar_buffer_bus(ctx, i),
 895                                            PAGE_SIZE, DMA_FROM_DEVICE);
 896                 ar_context_link_page(ctx, i);
 897                 i = ar_next_buffer_index(i);
 898         }
 899 }
 900
 901 static void ar_context_tasklet(unsigned long data)
 902 {
 903         struct ar_context *ctx = (struct ar_context *)data;
 904         unsigned int end_buffer_index, end_buffer_offset;
 905         void *p, *end;
 906
 907         p = ctx->pointer;
 908         if (!p)
 909                 return;
 910
 911         end_buffer_index = ar_search_last_active_buffer(ctx,
 912                                                         &end_buffer_offset);
 913         ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
 914         end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;
 915
 916         if (end_buffer_index < ar_first_buffer_index(ctx)) {
 917                 /*
 918                  * The filled part of the overall buffer wraps around; handle
 919                  * all packets up to the buffer end here.  If the last packet
 920                  * wraps around, its tail will be visible after the buffer end
 921                  * because the buffer start pages are mapped there again.
 922                  */
 923                 void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
 924                 p = handle_ar_packets(ctx, p, buffer_end);
 925                 if (p < buffer_end)
 926                         goto error;
 927                 /* adjust p to point back into the actual buffer */
 928                 p -= AR_BUFFERS * PAGE_SIZE;
 929         }
 930
 931         p = handle_ar_packets(ctx, p, end);
 932         if (p != end) {
 933                 if (p > end)
 934                         ar_context_abort(ctx, "inconsistent descriptor");
 935                 goto error;
 936         }
 937
 938         ctx->pointer = p;
 939         ar_recycle_buffers(ctx, end_buffer_index);
 940
 941         return;
 942
 943 error:
 944         ctx->pointer = NULL;
 945 }
 946
 947 static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
 948                            unsigned int descriptors_offset, u32 regs)
 949 {
 950         unsigned int i;
 951         dma_addr_t dma_addr;
 952         struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
 953         struct descriptor *d;
 954
 955         ctx->regs        = regs;
 956         ctx->ohci        = ohci;
 957         tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
 958
 959         for (i = 0; i < AR_BUFFERS; i++) {
 960                 ctx->pages[i] = alloc_page(GFP_KERNEL | GFP_DMA32);
 961                 if (!ctx->pages[i])
 962                         goto out_of_memory;
 963                 dma_addr = dma_map_page(ohci->card.device, ctx->pages[i],
 964                                         0, PAGE_SIZE, DMA_FROM_DEVICE);
 965                 if (dma_mapping_error(ohci->card.device, dma_addr)) {
 966                         __free_page(ctx->pages[i]);
 967                         ctx->pages[i] = NULL;
 968                         goto out_of_memory;
 969                 }
 970                 set_page_private(ctx->pages[i], dma_addr);
 971         }
 972
 973         for (i = 0; i < AR_BUFFERS; i++)
 974                 pages[i]              = ctx->pages[i];
 975         for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
 976                 pages[AR_BUFFERS + i] = ctx->pages[i];
 977         ctx->buffer = vm_map_ram(pages, AR_BUFFERS + AR_WRAPAROUND_PAGES,
 978                                  -1, PAGE_KERNEL);
 979         if (!ctx->buffer)
 980                 goto out_of_memory;
 981
 982         ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
 983         ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;
 984
 985         for (i = 0; i < AR_BUFFERS; i++) {
 986                 d = &ctx->descriptors[i];
 987                 d->req_count      = cpu_to_le16(PAGE_SIZE);
 988                 d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
 989                                                 DESCRIPTOR_STATUS |
 990                                                 DESCRIPTOR_BRANCH_ALWAYS);
 991                 d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
 992                 d->branch_address = cpu_to_le32(ctx->descriptors_bus +
 993                         ar_next_buffer_index(i) * sizeof(struct descriptor));
 994         }
 995
 996         return 0;
 997
 998 out_of_memory:
 999         ar_context_release(ctx);
1000
1001         return -ENOMEM;
1002 }
1003
1004 static void ar_context_run(struct ar_context *ctx)
1005 {
1006         unsigned int i;
1007
1008         for (i = 0; i < AR_BUFFERS; i++)
1009                 ar_context_link_page(ctx, i);
1010
1011         ctx->pointer = ctx->buffer;
1012
1013         reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
1014         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
1015 }
1016
1017 static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
1018 {
1019         __le16 branch;
1020
1021         branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);
1022
1023         /* figure out which descriptor the branch address goes in */
1024         if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
1025                 return d;
1026         else
1027                 return d + z - 1;
1028 }
1029
1030 static void context_tasklet(unsigned long data)
1031 {
1032         struct context *ctx = (struct context *) data;
1033         struct descriptor *d, *last;
1034         u32 address;
1035         int z;
1036         struct descriptor_buffer *desc;
1037
1038         desc = list_entry(ctx->buffer_list.next,
1039                         struct descriptor_buffer, list);
1040         last = ctx->last;
1041         while (last->branch_address != 0) {
1042                 struct descriptor_buffer *old_desc = desc;
1043                 address = le32_to_cpu(last->branch_address);
1044                 z = address & 0xf;
1045                 address &= ~0xf;
1046
1047                 /* If the branch address points to a buffer outside of the
1048                  * current buffer, advance to the next buffer. */
1049                 if (address < desc->buffer_bus ||
1050                                 address >= desc->buffer_bus + desc->used)
1051                         desc = list_entry(desc->list.next,
1052                                         struct descriptor_buffer, list);
1053                 d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
1054                 last = find_branch_descriptor(d, z);
1055
1056                 if (!ctx->callback(ctx, d, last))
1057                         break;
1058
1059                 if (old_desc != desc) {
1060                         /* If we've advanced to the next buffer, move the
1061                          * previous buffer to the free list. */
1062                         unsigned long flags;
1063                         old_desc->used = 0;
1064                         spin_lock_irqsave(&ctx->ohci->lock, flags);
1065                         list_move_tail(&old_desc->list, &ctx->buffer_list);
1066                         spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1067                 }
1068                 ctx->last = last;
1069         }
1070 }
1071
1072 /*
1073  * Allocate a new buffer and add it to the list of free buffers for this
1074  * context.  Must be called with ohci->lock held.
1075  */
1076 static int context_add_buffer(struct context *ctx)
1077 {
1078         struct descriptor_buffer *desc;
1079         dma_addr_t uninitialized_var(bus_addr);
1080         int offset;
1081
1082         /*
1083          * 16MB of descriptors should be far more than enough for any DMA
1084          * program.  This will catch run-away userspace or DoS attacks.
1085          */
1086         if (ctx->total_allocation >= 16*1024*1024)
1087                 return -ENOMEM;
1088
1089         desc = dma_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE,
1090                         &bus_addr, GFP_ATOMIC);
1091         if (!desc)
1092                 return -ENOMEM;
1093
1094         offset = (void *)&desc->buffer - (void *)desc;
1095         desc->buffer_size = PAGE_SIZE - offset;
1096         desc->buffer_bus = bus_addr + offset;
1097         desc->used = 0;
1098
1099         list_add_tail(&desc->list, &ctx->buffer_list);
1100         ctx->total_allocation += PAGE_SIZE;
1101
1102         return 0;
1103 }
1104
1105 static int context_init(struct context *ctx, struct fw_ohci *ohci,
1106                         u32 regs, descriptor_callback_t callback)
1107 {
1108         ctx->ohci = ohci;
1109         ctx->regs = regs;
1110         ctx->total_allocation = 0;
1111
1112         INIT_LIST_HEAD(&ctx->buffer_list);
1113         if (context_add_buffer(ctx) < 0)
1114                 return -ENOMEM;
1115
1116         ctx->buffer_tail = list_entry(ctx->buffer_list.next,
1117                         struct descriptor_buffer, list);
1118
1119         tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
1120         ctx->callback = callback;
1121
1122         /*
1123          * We put a dummy descriptor in the buffer that has a NULL
1124          * branch address and looks like it's been sent.  That way we
1125          * have a descriptor to append DMA programs to.
1126          */
1127         memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
1128         ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
1129         ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
1130         ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
1131         ctx->last = ctx->buffer_tail->buffer;
1132         ctx->prev = ctx->buffer_tail->buffer;
1133
1134         return 0;
1135 }
1136
1137 static void context_release(struct context *ctx)
1138 {
1139         struct fw_card *card = &ctx->ohci->card;
1140         struct descriptor_buffer *desc, *tmp;
1141
1142         list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list)
1143                 dma_free_coherent(card->device, PAGE_SIZE, desc,
1144                         desc->buffer_bus -
1145                         ((void *)&desc->buffer - (void *)desc));
1146 }
1147
1148 /* Must be called with ohci->lock held */
1149 static struct descriptor *context_get_descriptors(struct context *ctx,
1150                                                   int z, dma_addr_t *d_bus)
1151 {
1152         struct descriptor *d = NULL;
1153         struct descriptor_buffer *desc = ctx->buffer_tail;
1154
1155         if (z * sizeof(*d) > desc->buffer_size)
1156                 return NULL;
1157
1158         if (z * sizeof(*d) > desc->buffer_size - desc->used) {
1159                 /* No room for the descriptor in this buffer, so advance to the
1160                  * next one. */
1161
1162                 if (desc->list.next == &ctx->buffer_list) {
1163                         /* If there is no free buffer next in the list,
1164                          * allocate one. */
1165                         if (context_add_buffer(ctx) < 0)
1166                                 return NULL;
1167                 }
1168                 desc = list_entry(desc->list.next,
1169                                 struct descriptor_buffer, list);
1170                 ctx->buffer_tail = desc;
1171         }
1172
1173         d = desc->buffer + desc->used / sizeof(*d);
1174         memset(d, 0, z * sizeof(*d));
1175         *d_bus = desc->buffer_bus + desc->used;
1176
1177         return d;
1178 }
1179
1180 static void context_run(struct context *ctx, u32 extra)
1181 {
1182         struct fw_ohci *ohci = ctx->ohci;
1183
1184         reg_write(ohci, COMMAND_PTR(ctx->regs),
1185                   le32_to_cpu(ctx->last->branch_address));
1186         reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
1187         reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
1188         ctx->running = true;
1189         flush_writes(ohci);
1190 }
1191
1192 static void context_append(struct context *ctx,
1193                            struct descriptor *d, int z, int extra)
1194 {
1195         dma_addr_t d_bus;
1196         struct descriptor_buffer *desc = ctx->buffer_tail;
1197
1198         d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);
1199
1200         desc->used += (z + extra) * sizeof(*d);
1201
1202         wmb(); /* finish init of new descriptors before branch_address update */
1203         ctx->prev->branch_address = cpu_to_le32(d_bus | z);
1204         ctx->prev = find_branch_descriptor(d, z);
1205 }
1206
1207 static void context_stop(struct context *ctx)
1208 {
1209         u32 reg;
1210         int i;
1211
1212         reg_write(ctx->ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
1213         ctx->running = false;
1214
1215         for (i = 0; i < 1000; i++) {
1216                 reg = reg_read(ctx->ohci, CONTROL_SET(ctx->regs));
1217                 if ((reg & CONTEXT_ACTIVE) == 0)
1218                         return;
1219
1220                 if (i)
1221                         udelay(10);
1222         }
1223         fw_error("Error: DMA context still active (0x%08x)\n", reg);
1224 }
1225
1226 struct driver_data {
1227         u8 inline_data[8];
1228         struct fw_packet *packet;
1229 };
1230
1231 /*
1232  * This function apppends a packet to the DMA queue for transmission.
1233  * Must always be called with the ochi->lock held to ensure proper
1234  * generation handling and locking around packet queue manipulation.
1235  */
1236 static int at_context_queue_packet(struct context *ctx,
1237                                    struct fw_packet *packet)
1238 {
1239         struct fw_ohci *ohci = ctx->ohci;
1240         dma_addr_t d_bus, uninitialized_var(payload_bus);
1241         struct driver_data *driver_data;
1242         struct descriptor *d, *last;
1243         __le32 *header;
1244         int z, tcode;
1245
1246         d = context_get_descriptors(ctx, 4, &d_bus);
1247         if (d == NULL) {
1248                 packet->ack = RCODE_SEND_ERROR;
1249                 return -1;
1250         }
1251
1252         d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
1253         d[0].res_count = cpu_to_le16(packet->timestamp);
1254
1255         /*
1256          * The DMA format for asyncronous link packets is different
1257          * from the IEEE1394 layout, so shift the fields around
1258          * accordingly.
1259          */
1260
1261         tcode = (packet->header[0] >> 4) & 0x0f;
1262         header = (__le32 *) &d[1];
1263         switch (tcode) {
1264         case TCODE_WRITE_QUADLET_REQUEST:
1265         case TCODE_WRITE_BLOCK_REQUEST:
1266         case TCODE_WRITE_RESPONSE:
1267         case TCODE_READ_QUADLET_REQUEST:
1268         case TCODE_READ_BLOCK_REQUEST:
1269         case TCODE_READ_QUADLET_RESPONSE:
1270         case TCODE_READ_BLOCK_RESPONSE:
1271         case TCODE_LOCK_REQUEST:
1272         case TCODE_LOCK_RESPONSE:
1273                 header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1274                                         (packet->speed << 16));
1275                 header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
1276                                         (packet->header[0] & 0xffff0000));
1277                 header[2] = cpu_to_le32(packet->header[2]);
1278
1279                 if (TCODE_IS_BLOCK_PACKET(tcode))
1280                         header[3] = cpu_to_le32(packet->header[3]);
1281                 else
1282                         header[3] = (__force __le32) packet->header[3];
1283
1284                 d[0].req_count = cpu_to_le16(packet->header_length);
1285                 break;
1286
1287         case TCODE_LINK_INTERNAL:
1288                 header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
1289                                         (packet->speed << 16));
1290                 header[1] = cpu_to_le32(packet->header[1]);
1291                 header[2] = cpu_to_le32(packet->header[2]);
1292                 d[0].req_count = cpu_to_le16(12);
1293
1294                 if (is_ping_packet(&packet->header[1]))
1295                         d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
1296                 break;
1297
1298         case TCODE_STREAM_DATA:
1299                 header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
1300                                         (packet->speed << 16));
1301                 header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
1302                 d[0].req_count = cpu_to_le16(8);
1303                 break;
1304
1305         default:
1306                 /* BUG(); */
1307                 packet->ack = RCODE_SEND_ERROR;
1308                 return -1;
1309         }
1310
1311         BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
1312         driver_data = (struct driver_data *) &d[3];
1313         driver_data->packet = packet;
1314         packet->driver_data = driver_data;
1315
1316         if (packet->payload_length > 0) {
1317                 if (packet->payload_length > sizeof(driver_data->inline_data)) {
1318                         payload_bus = dma_map_single(ohci->card.device,
1319                                                      packet->payload,
1320                                                      packet->payload_length,
1321                                                      DMA_TO_DEVICE);
1322                         if (dma_mapping_error(ohci->card.device, payload_bus)) {
1323                                 packet->ack = RCODE_SEND_ERROR;
1324                                 return -1;
1325                         }
1326                         packet->payload_bus     = payload_bus;
1327                         packet->payload_mapped  = true;
1328                 } else {
1329                         memcpy(driver_data->inline_data, packet->payload,
1330                                packet->payload_length);
1331                         payload_bus = d_bus + 3 * sizeof(*d);
1332                 }
1333
1334                 d[2].req_count    = cpu_to_le16(packet->payload_length);
1335                 d[2].data_address = cpu_to_le32(payload_bus);
1336                 last = &d[2];
1337                 z = 3;
1338         } else {
1339                 last = &d[0];
1340                 z = 2;
1341         }
1342
1343         last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
1344                                      DESCRIPTOR_IRQ_ALWAYS |
1345                                      DESCRIPTOR_BRANCH_ALWAYS);
1346
1347         /* FIXME: Document how the locking works. */
1348         if (ohci->generation != packet->generation) {
1349                 if (packet->payload_mapped)
1350                         dma_unmap_single(ohci->card.device, payload_bus,
1351                                          packet->payload_length, DMA_TO_DEVICE);
1352                 packet->ack = RCODE_GENERATION;
1353                 return -1;
1354         }
1355
1356         context_append(ctx, d, z, 4 - z);
1357
1358         if (ctx->running)
1359                 reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
1360         else
1361                 context_run(ctx, 0);
1362
1363         return 0;
1364 }
1365
1366 static void at_context_flush(struct context *ctx)
1367 {
1368         tasklet_disable(&ctx->tasklet);
1369
1370         ctx->flushing = true;
1371         context_tasklet((unsigned long)ctx);
1372         ctx->flushing = false;
1373
1374         tasklet_enable(&ctx->tasklet);
1375 }
1376
1377 static int handle_at_packet(struct context *context,
1378                             struct descriptor *d,
1379                             struct descriptor *last)
1380 {
1381         struct driver_data *driver_data;
1382         struct fw_packet *packet;
1383         struct fw_ohci *ohci = context->ohci;
1384         int evt;
1385
1386         if (last->transfer_status == 0 && !context->flushing)
1387                 /* This descriptor isn't done yet, stop iteration. */
1388                 return 0;
1389
1390         driver_data = (struct driver_data *) &d[3];
1391         packet = driver_data->packet;
1392         if (packet == NULL)
1393                 /* This packet was cancelled, just continue. */
1394                 return 1;
1395
1396         if (packet->payload_mapped)
1397                 dma_unmap_single(ohci->card.device, packet->payload_bus,
1398                                  packet->payload_length, DMA_TO_DEVICE);
1399
1400         evt = le16_to_cpu(last->transfer_status) & 0x1f;
1401         packet->timestamp = le16_to_cpu(last->res_count);
1402
1403         log_ar_at_event('T', packet->speed, packet->header, evt);
1404
1405         switch (evt) {
1406         case OHCI1394_evt_timeout:
1407                 /* Async response transmit timed out. */
1408                 packet->ack = RCODE_CANCELLED;
1409                 break;
1410
1411         case OHCI1394_evt_flushed:
1412                 /*
1413                  * The packet was flushed should give same error as
1414                  * when we try to use a stale generation count.
1415                  */
1416                 packet->ack = RCODE_GENERATION;
1417                 break;
1418
1419         case OHCI1394_evt_missing_ack:
1420                 if (context->flushing)
1421                         packet->ack = RCODE_GENERATION;
1422                 else {
1423                         /*
1424                          * Using a valid (current) generation count, but the
1425                          * node is not on the bus or not sending acks.
1426                          */
1427                         packet->ack = RCODE_NO_ACK;
1428                 }
1429                 break;
1430
1431         case ACK_COMPLETE + 0x10:
1432         case ACK_PENDING + 0x10:
1433         case ACK_BUSY_X + 0x10:
1434         case ACK_BUSY_A + 0x10:
1435         case ACK_BUSY_B + 0x10:
1436         case ACK_DATA_ERROR + 0x10:
1437         case ACK_TYPE_ERROR + 0x10:
1438                 packet->ack = evt - 0x10;
1439                 break;
1440
1441         case OHCI1394_evt_no_status:
1442                 if (context->flushing) {
1443                         packet->ack = RCODE_GENERATION;
1444                         break;
1445                 }
1446                 /* fall through */
1447
1448         default:
1449                 packet->ack = RCODE_SEND_ERROR;
1450                 break;
1451         }
1452
1453         packet->callback(packet, &ohci->card, packet->ack);
1454
1455         return 1;
1456 }
1457
1458 #define HEADER_GET_DESTINATION(q)       (((q) >> 16) & 0xffff)
1459 #define HEADER_GET_TCODE(q)             (((q) >> 4) & 0x0f)
1460 #define HEADER_GET_OFFSET_HIGH(q)       (((q) >> 0) & 0xffff)
1461 #define HEADER_GET_DATA_LENGTH(q)       (((q) >> 16) & 0xffff)
1462 #define HEADER_GET_EXTENDED_TCODE(q)    (((q) >> 0) & 0xffff)
1463
1464 static void handle_local_rom(struct fw_ohci *ohci,
1465                              struct fw_packet *packet, u32 csr)
1466 {
1467         struct fw_packet response;
1468         int tcode, length, i;
1469
1470         tcode = HEADER_GET_TCODE(packet->header[0]);
1471         if (TCODE_IS_BLOCK_PACKET(tcode))
1472                 length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1473         else
1474                 length = 4;
1475
1476         i = csr - CSR_CONFIG_ROM;
1477         if (i + length > CONFIG_ROM_SIZE) {
1478                 fw_fill_response(&response, packet->header,
1479                                  RCODE_ADDRESS_ERROR, NULL, 0);
1480         } else if (!TCODE_IS_READ_REQUEST(tcode)) {
1481                 fw_fill_response(&response, packet->header,
1482                                  RCODE_TYPE_ERROR, NULL, 0);
1483         } else {
1484                 fw_fill_response(&response, packet->header, RCODE_COMPLETE,
1485                                  (void *) ohci->config_rom + i, length);
1486         }
1487
1488         fw_core_handle_response(&ohci->card, &response);
1489 }
1490
1491 static void handle_local_lock(struct fw_ohci *ohci,
1492                               struct fw_packet *packet, u32 csr)
1493 {
1494         struct fw_packet response;
1495         int tcode, length, ext_tcode, sel, try;
1496         __be32 *payload, lock_old;
1497         u32 lock_arg, lock_data;
1498
1499         tcode = HEADER_GET_TCODE(packet->header[0]);
1500         length = HEADER_GET_DATA_LENGTH(packet->header[3]);
1501         payload = packet->payload;
1502         ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);
1503
1504         if (tcode == TCODE_LOCK_REQUEST &&
1505             ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
1506                 lock_arg = be32_to_cpu(payload[0]);
1507                 lock_data = be32_to_cpu(payload[1]);
1508         } else if (tcode == TCODE_READ_QUADLET_REQUEST) {
1509                 lock_arg = 0;
1510                 lock_data = 0;
1511         } else {
1512                 fw_fill_response(&response, packet->header,
1513                                  RCODE_TYPE_ERROR, NULL, 0);
1514                 goto out;
1515         }
1516
1517         sel = (csr - CSR_BUS_MANAGER_ID) / 4;
1518         reg_write(ohci, OHCI1394_CSRData, lock_data);
1519         reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
1520         reg_write(ohci, OHCI1394_CSRControl, sel);
1521
1522         for (try = 0; try < 20; try++)
1523                 if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
1524                         lock_old = cpu_to_be32(reg_read(ohci,
1525                                                         OHCI1394_CSRData));
1526                         fw_fill_response(&response, packet->header,
1527                                          RCODE_COMPLETE,
1528                                          &lock_old, sizeof(lock_old));
1529                         goto out;
1530                 }
1531
1532         fw_error("swap not done (CSR lock timeout)\n");
1533         fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);
1534
1535  out:
1536         fw_core_handle_response(&ohci->card, &response);
1537 }
1538
1539 static void handle_local_request(struct context *ctx, struct fw_packet *packet)
1540 {
1541         u64 offset, csr;
1542
1543         if (ctx == &ctx->ohci->at_request_ctx) {
1544                 packet->ack = ACK_PENDING;
1545                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1546         }
1547
1548         offset =
1549                 ((unsigned long long)
1550                  HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
1551                 packet->header[2];
1552         csr = offset - CSR_REGISTER_BASE;
1553
1554         /* Handle config rom reads. */
1555         if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
1556                 handle_local_rom(ctx->ohci, packet, csr);
1557         else switch (csr) {
1558         case CSR_BUS_MANAGER_ID:
1559         case CSR_BANDWIDTH_AVAILABLE:
1560         case CSR_CHANNELS_AVAILABLE_HI:
1561         case CSR_CHANNELS_AVAILABLE_LO:
1562                 handle_local_lock(ctx->ohci, packet, csr);
1563                 break;
1564         default:
1565                 if (ctx == &ctx->ohci->at_request_ctx)
1566                         fw_core_handle_request(&ctx->ohci->card, packet);
1567                 else
1568                         fw_core_handle_response(&ctx->ohci->card, packet);
1569                 break;
1570         }
1571
1572         if (ctx == &ctx->ohci->at_response_ctx) {
1573                 packet->ack = ACK_COMPLETE;
1574                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1575         }
1576 }
1577
1578 static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
1579 {
1580         unsigned long flags;
1581         int ret;
1582
1583         spin_lock_irqsave(&ctx->ohci->lock, flags);
1584
1585         if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
1586             ctx->ohci->generation == packet->generation) {
1587                 spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1588                 handle_local_request(ctx, packet);
1589                 return;
1590         }
1591
1592         ret = at_context_queue_packet(ctx, packet);
1593         spin_unlock_irqrestore(&ctx->ohci->lock, flags);
1594
1595         if (ret < 0)
1596                 packet->callback(packet, &ctx->ohci->card, packet->ack);
1597
1598 }
1599
1600 static void detect_dead_context(struct fw_ohci *ohci,
1601                                 const char *name, unsigned int regs)
1602 {
1603         u32 ctl;
1604
1605         ctl = reg_read(ohci, CONTROL_SET(regs));
1606         if (ctl & CONTEXT_DEAD) {
1607 #ifdef CONFIG_FIREWIRE_OHCI_DEBUG
1608                 fw_error("DMA context %s has stopped, error code: %s\n",
1609                          name, evts[ctl & 0x1f]);
1610 #else
1611                 fw_error("DMA context %s has stopped, error code: %#x\n",
1612                          name, ctl & 0x1f);
1613 #endif
1614         }
1615 }
1616
1617 static void handle_dead_contexts(struct fw_ohci *ohci)
1618 {
1619         unsigned int i;
1620         char name[8];
1621
1622         detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
1623         detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
1624         detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
1625         detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
1626         for (i = 0; i < 32; ++i) {
1627                 if (!(ohci->it_context_support & (1 << i)))
1628                         continue;
1629                 sprintf(name, "IT%u", i);
1630                 detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
1631         }
1632         for (i = 0; i < 32; ++i) {
1633                 if (!(ohci->ir_context_support & (1 << i)))
1634                         continue;
1635                 sprintf(name, "IR%u", i);
1636                 detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
1637         }
1638         /* TODO: maybe try to flush and restart the dead contexts */
1639 }
1640
1641 static u32 cycle_timer_ticks(u32 cycle_timer)
1642 {
1643         u32 ticks;
1644
1645         ticks = cycle_timer & 0xfff;
1646         ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
1647         ticks += (3072 * 8000) * (cycle_timer >> 25);
1648
1649         return ticks;
1650 }
1651
1652 /*
1653  * Some controllers exhibit one or more of the following bugs when updating the
1654  * iso cycle timer register:
1655  *  - When the lowest six bits are wrapping around to zero, a read that happens
1656  *    at the same time will return garbage in the lowest ten bits.
1657  *  - When the cycleOffset field wraps around to zero, the cycleCount field is
1658  *    not incremented for about 60 ns.
1659  *  - Occasionally, the entire register reads zero.
1660  *
1661  * To catch these, we read the register three times and ensure that the
1662  * difference between each two consecutive reads is approximately the same, i.e.
1663  * less than twice the other.  Furthermore, any negative difference indicates an
1664  * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
1665  * execute, so we have enough precision to compute the ratio of the differences.)
1666  */
1667 static u32 get_cycle_time(struct fw_ohci *ohci)
1668 {
1669         u32 c0, c1, c2;
1670         u32 t0, t1, t2;
1671         s32 diff01, diff12;
1672         int i;
1673
1674         c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1675
1676         if (ohci->quirks & QUIRK_CYCLE_TIMER) {
1677                 i = 0;
1678                 c1 = c2;
1679                 c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1680                 do {
1681                         c0 = c1;
1682                         c1 = c2;
1683                         c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
1684                         t0 = cycle_timer_ticks(c0);
1685                         t1 = cycle_timer_ticks(c1);
1686                         t2 = cycle_timer_ticks(c2);
1687                         diff01 = t1 - t0;
1688                         diff12 = t2 - t1;
1689                 } while ((diff01 <= 0 || diff12 <= 0 ||
1690                           diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
1691                          && i++ < 20);
1692         }
1693
1694         return c2;
1695 }
1696
1697 /*
1698  * This function has to be called at least every 64 seconds.  The bus_time
1699  * field stores not only the upper 25 bits of the BUS_TIME register but also
1700  * the most significant bit of the cycle timer in bit 6 so that we can detect
1701  * changes in this bit.
1702  */
1703 static u32 update_bus_time(struct fw_ohci *ohci)
1704 {
1705         u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;
1706
1707         if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
1708                 ohci->bus_time += 0x40;
1709
1710         return ohci->bus_time | cycle_time_seconds;
1711 }
1712
1713 static void bus_reset_tasklet(unsigned long data)
1714 {
1715         struct fw_ohci *ohci = (struct fw_ohci *)data;
1716         int self_id_count, i, j, reg;
1717         int generation, new_generation;
1718         unsigned long flags;
1719         void *free_rom = NULL;
1720         dma_addr_t free_rom_bus = 0;
1721         bool is_new_root;
1722
1723         reg = reg_read(ohci, OHCI1394_NodeID);
1724         if (!(reg & OHCI1394_NodeID_idValid)) {
1725                 fw_notify("node ID not valid, new bus reset in progress\n");
1726                 return;
1727         }
1728         if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
1729                 fw_notify("malconfigured bus\n");
1730                 return;
1731         }
1732         ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
1733                                OHCI1394_NodeID_nodeNumber);
1734
1735         is_new_root = (reg & OHCI1394_NodeID_root) != 0;
1736         if (!(ohci->is_root && is_new_root))
1737                 reg_write(ohci, OHCI1394_LinkControlSet,
1738                           OHCI1394_LinkControl_cycleMaster);
1739         ohci->is_root = is_new_root;
1740
1741         reg = reg_read(ohci, OHCI1394_SelfIDCount);
1742         if (reg & OHCI1394_SelfIDCount_selfIDError) {
1743                 fw_notify("inconsistent self IDs\n");
1744                 return;
1745         }
1746         /*
1747          * The count in the SelfIDCount register is the number of
1748          * bytes in the self ID receive buffer.  Since we also receive
1749          * the inverted quadlets and a header quadlet, we shift one
1750          * bit extra to get the actual number of self IDs.
1751          */
1752         self_id_count = (reg >> 3) & 0xff;
1753         if (self_id_count == 0 || self_id_count > 252) {
1754                 fw_notify("inconsistent self IDs\n");
1755                 return;
1756         }
1757         generation = (cond_le32_to_cpu(ohci->self_id_cpu[0]) >> 16) & 0xff;
1758         rmb();
1759
1760         for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
1761                 if (ohci->self_id_cpu[i] != ~ohci->self_id_cpu[i + 1]) {
1762                         fw_notify("inconsistent self IDs\n");
1763                         return;
1764                 }
1765                 ohci->self_id_buffer[j] =
1766                                 cond_le32_to_cpu(ohci->self_id_cpu[i]);
1767         }
1768         rmb();
1769
1770         /*
1771          * Check the consistency of the self IDs we just read.  The
1772          * problem we face is that a new bus reset can start while we
1773          * read out the self IDs from the DMA buffer. If this happens,
1774          * the DMA buffer will be overwritten with new self IDs and we
1775          * will read out inconsistent data.  The OHCI specification
1776          * (section 11.2) recommends a technique similar to
1777          * linux/seqlock.h, where we remember the generation of the
1778          * self IDs in the buffer before reading them out and compare
1779          * it to the current generation after reading them out.  If
1780          * the two generations match we know we have a consistent set
1781          * of self IDs.
1782          */
1783
1784         new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
1785         if (new_generation != generation) {
1786                 fw_notify("recursive bus reset detected, "
1787                           "discarding self ids\n");
1788                 return;
1789         }
1790
1791         /* FIXME: Document how the locking works. */
1792         spin_lock_irqsave(&ohci->lock, flags);
1793
1794         ohci->generation = -1; /* prevent AT packet queueing */
1795         context_stop(&ohci->at_request_ctx);
1796         context_stop(&ohci->at_response_ctx);
1797
1798         spin_unlock_irqrestore(&ohci->lock, flags);
1799
1800         /*
1801          * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
1802          * packets in the AT queues and software needs to drain them.
1803          * Some OHCI 1.1 controllers (JMicron) apparently require this too.
1804          */
1805         at_context_flush(&ohci->at_request_ctx);
1806         at_context_flush(&ohci->at_response_ctx);
1807
1808         spin_lock_irqsave(&ohci->lock, flags);
1809
1810         ohci->generation = generation;
1811         reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
1812
1813         if (ohci->quirks & QUIRK_RESET_PACKET)
1814                 ohci->request_generation = generation;
1815
1816         /*
1817          * This next bit is unrelated to the AT context stuff but we
1818          * have to do it under the spinlock also.  If a new config rom
1819          * was set up before this reset, the old one is now no longer
1820          * in use and we can free it. Update the config rom pointers
1821          * to point to the current config rom and clear the
1822          * next_config_rom pointer so a new update can take place.
1823          */
1824
1825         if (ohci->next_config_rom != NULL) {
1826                 if (ohci->next_config_rom != ohci->config_rom) {
1827                         free_rom      = ohci->config_rom;
1828                         free_rom_bus  = ohci->config_rom_bus;
1829                 }
1830                 ohci->config_rom      = ohci->next_config_rom;
1831                 ohci->config_rom_bus  = ohci->next_config_rom_bus;
1832                 ohci->next_config_rom = NULL;
1833
1834                 /*
1835                  * Restore config_rom image and manually update
1836                  * config_rom registers.  Writing the header quadlet
1837                  * will indicate that the config rom is ready, so we
1838                  * do that last.
1839                  */
1840                 reg_write(ohci, OHCI1394_BusOptions,
1841                           be32_to_cpu(ohci->config_rom[2]));
1842                 ohci->config_rom[0] = ohci->next_header;
1843                 reg_write(ohci, OHCI1394_ConfigROMhdr,
1844                           be32_to_cpu(ohci->next_header));
1845         }
1846
1847 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
1848         reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
1849         reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
1850 #endif
1851
1852         spin_unlock_irqrestore(&ohci->lock, flags);
1853
1854         if (free_rom)
1855                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
1856                                   free_rom, free_rom_bus);
1857
1858         log_selfids(ohci->node_id, generation,
1859                     self_id_count, ohci->self_id_buffer);
1860
1861         fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
1862                                  self_id_count, ohci->self_id_buffer,
1863                                  ohci->csr_state_setclear_abdicate);
1864         ohci->csr_state_setclear_abdicate = false;
1865 }
1866
1867 static irqreturn_t irq_handler(int irq, void *data)
1868 {
1869         struct fw_ohci *ohci = data;
1870         u32 event, iso_event;
1871         int i;
1872
1873         event = reg_read(ohci, OHCI1394_IntEventClear);
1874
1875         if (!event || !~event)
1876                 return IRQ_NONE;
1877
1878         /*
1879          * busReset and postedWriteErr must not be cleared yet
1880          * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
1881          */
1882         reg_write(ohci, OHCI1394_IntEventClear,
1883                   event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
1884         log_irqs(event);
1885
1886         if (event & OHCI1394_selfIDComplete)
1887                 tasklet_schedule(&ohci->bus_reset_tasklet);
1888
1889         if (event & OHCI1394_RQPkt)
1890                 tasklet_schedule(&ohci->ar_request_ctx.tasklet);
1891
1892         if (event & OHCI1394_RSPkt)
1893                 tasklet_schedule(&ohci->ar_response_ctx.tasklet);
1894
1895         if (event & OHCI1394_reqTxComplete)
1896                 tasklet_schedule(&ohci->at_request_ctx.tasklet);
1897
1898         if (event & OHCI1394_respTxComplete)
1899                 tasklet_schedule(&ohci->at_response_ctx.tasklet);
1900
1901         if (event & OHCI1394_isochRx) {
1902                 iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
1903                 reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
1904
1905                 while (iso_event) {
1906                         i = ffs(iso_event) - 1;
1907                         tasklet_schedule(
1908                                 &ohci->ir_context_list[i].context.tasklet);
1909                         iso_event &= ~(1 << i);
1910                 }
1911         }
1912
1913         if (event & OHCI1394_isochTx) {
1914                 iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
1915                 reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
1916
1917                 while (iso_event) {
1918                         i = ffs(iso_event) - 1;
1919                         tasklet_schedule(
1920                                 &ohci->it_context_list[i].context.tasklet);
1921                         iso_event &= ~(1 << i);
1922                 }
1923         }
1924
1925         if (unlikely(event & OHCI1394_regAccessFail))
1926                 fw_error("Register access failure - "
1927                          "please notify linux1394-devel@lists.sf.net\n");
1928
1929         if (unlikely(event & OHCI1394_postedWriteErr)) {
1930                 reg_read(ohci, OHCI1394_PostedWriteAddressHi);
1931                 reg_read(ohci, OHCI1394_PostedWriteAddressLo);
1932                 reg_write(ohci, OHCI1394_IntEventClear,
1933                           OHCI1394_postedWriteErr);
1934                 fw_error("PCI posted write error\n");
1935         }
1936
1937         if (unlikely(event & OHCI1394_cycleTooLong)) {
1938                 if (printk_ratelimit())
1939                         fw_notify("isochronous cycle too long\n");
1940                 reg_write(ohci, OHCI1394_LinkControlSet,
1941                           OHCI1394_LinkControl_cycleMaster);
1942         }
1943
1944         if (unlikely(event & OHCI1394_cycleInconsistent)) {
1945                 /*
1946                  * We need to clear this event bit in order to make
1947                  * cycleMatch isochronous I/O work.  In theory we should
1948                  * stop active cycleMatch iso contexts now and restart
1949                  * them at least two cycles later.  (FIXME?)
1950                  */
1951                 if (printk_ratelimit())
1952                         fw_notify("isochronous cycle inconsistent\n");
1953         }
1954
1955         if (unlikely(event & OHCI1394_unrecoverableError))
1956                 handle_dead_contexts(ohci);
1957
1958         if (event & OHCI1394_cycle64Seconds) {
1959                 spin_lock(&ohci->lock);
1960                 update_bus_time(ohci);
1961                 spin_unlock(&ohci->lock);
1962         } else
1963                 flush_writes(ohci);
1964
1965         return IRQ_HANDLED;
1966 }
1967
1968 static int software_reset(struct fw_ohci *ohci)
1969 {
1970         u32 val;
1971         int i;
1972
1973         reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
1974         for (i = 0; i < 500; i++) {
1975                 val = reg_read(ohci, OHCI1394_HCControlSet);
1976                 if (!~val)
1977                         return -ENODEV; /* Card was ejected. */
1978
1979                 if (!(val & OHCI1394_HCControl_softReset))
1980                         return 0;
1981
1982                 msleep(1);
1983         }
1984
1985         return -EBUSY;
1986 }
1987
1988 static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
1989 {
1990         size_t size = length * 4;
1991
1992         memcpy(dest, src, size);
1993         if (size < CONFIG_ROM_SIZE)
1994                 memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
1995 }
1996
1997 static int configure_1394a_enhancements(struct fw_ohci *ohci)
1998 {
1999         bool enable_1394a;
2000         int ret, clear, set, offset;
2001
2002         /* Check if the driver should configure link and PHY. */
2003         if (!(reg_read(ohci, OHCI1394_HCControlSet) &
2004               OHCI1394_HCControl_programPhyEnable))
2005                 return 0;
2006
2007         /* Paranoia: check whether the PHY supports 1394a, too. */
2008         enable_1394a = false;
2009         ret = read_phy_reg(ohci, 2);
2010         if (ret < 0)
2011                 return ret;
2012         if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
2013                 ret = read_paged_phy_reg(ohci, 1, 8);
2014                 if (ret < 0)
2015                         return ret;
2016                 if (ret >= 1)
2017                         enable_1394a = true;
2018         }
2019
2020         if (ohci->quirks & QUIRK_NO_1394A)
2021                 enable_1394a = false;
2022
2023         /* Configure PHY and link consistently. */
2024         if (enable_1394a) {
2025                 clear = 0;
2026                 set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2027         } else {
2028                 clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
2029                 set = 0;
2030         }
2031         ret = update_phy_reg(ohci, 5, clear, set);
2032         if (ret < 0)
2033                 return ret;
2034
2035         if (enable_1394a)
2036                 offset = OHCI1394_HCControlSet;
2037         else
2038                 offset = OHCI1394_HCControlClear;
2039         reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);
2040
2041         /* Clean up: configuration has been taken care of. */
2042         reg_write(ohci, OHCI1394_HCControlClear,
2043                   OHCI1394_HCControl_programPhyEnable);
2044
2045         return 0;
2046 }
2047
2048 static int ohci_enable(struct fw_card *card,
2049                        const __be32 *config_rom, size_t length)
2050 {
2051         struct fw_ohci *ohci = fw_ohci(card);
2052         struct pci_dev *dev = to_pci_dev(card->device);
2053         u32 lps, seconds, version, irqs;
2054         int i, ret;
2055
2056         if (software_reset(ohci)) {
2057                 fw_error("Failed to reset ohci card.\n");
2058                 return -EBUSY;
2059         }
2060
2061         /*
2062          * Now enable LPS, which we need in order to start accessing
2063          * most of the registers.  In fact, on some cards (ALI M5251),
2064          * accessing registers in the SClk domain without LPS enabled
2065          * will lock up the machine.  Wait 50msec to make sure we have
2066          * full link enabled.  However, with some cards (well, at least
2067          * a JMicron PCIe card), we have to try again sometimes.
2068          */
2069         reg_write(ohci, OHCI1394_HCControlSet,
2070                   OHCI1394_HCControl_LPS |
2071                   OHCI1394_HCControl_postedWriteEnable);
2072         flush_writes(ohci);
2073
2074         for (lps = 0, i = 0; !lps && i < 3; i++) {
2075                 msleep(50);
2076                 lps = reg_read(ohci, OHCI1394_HCControlSet) &
2077                       OHCI1394_HCControl_LPS;
2078         }
2079
2080         if (!lps) {
2081                 fw_error("Failed to set Link Power Status\n");
2082                 return -EIO;
2083         }
2084
2085         reg_write(ohci, OHCI1394_HCControlClear,
2086                   OHCI1394_HCControl_noByteSwapData);
2087
2088         reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
2089         reg_write(ohci, OHCI1394_LinkControlSet,
2090                   OHCI1394_LinkControl_cycleTimerEnable |
2091                   OHCI1394_LinkControl_cycleMaster);
2092
2093         reg_write(ohci, OHCI1394_ATRetries,
2094                   OHCI1394_MAX_AT_REQ_RETRIES |
2095                   (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
2096                   (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
2097                   (200 << 16));
2098
2099         seconds = lower_32_bits(get_seconds());
2100         reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
2101         ohci->bus_time = seconds & ~0x3f;
2102
2103         version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
2104         if (version >= OHCI_VERSION_1_1) {
2105                 reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
2106                           0xfffffffe);
2107                 card->broadcast_channel_auto_allocated = true;
2108         }
2109
2110         /* Get implemented bits of the priority arbitration request counter. */
2111         reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
2112         ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
2113         reg_write(ohci, OHCI1394_FairnessControl, 0);
2114         card->priority_budget_implemented = ohci->pri_req_max != 0;
2115
2116         reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
2117         reg_write(ohci, OHCI1394_IntEventClear, ~0);
2118         reg_write(ohci, OHCI1394_IntMaskClear, ~0);
2119
2120         ret = configure_1394a_enhancements(ohci);
2121         if (ret < 0)
2122                 return ret;
2123
2124         /* Activate link_on bit and contender bit in our self ID packets.*/
2125         ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
2126         if (ret < 0)
2127                 return ret;
2128
2129         /*
2130          * When the link is not yet enabled, the atomic config rom
2131          * update mechanism described below in ohci_set_config_rom()
2132          * is not active.  We have to update ConfigRomHeader and
2133          * BusOptions manually, and the write to ConfigROMmap takes
2134          * effect immediately.  We tie this to the enabling of the
2135          * link, so we have a valid config rom before enabling - the
2136          * OHCI requires that ConfigROMhdr and BusOptions have valid
2137          * values before enabling.
2138          *
2139          * However, when the ConfigROMmap is written, some controllers
2140          * always read back quadlets 0 and 2 from the config rom to
2141          * the ConfigRomHeader and BusOptions registers on bus reset.
2142          * They shouldn't do that in this initial case where the link
2143          * isn't enabled.  This means we have to use the same
2144          * workaround here, setting the bus header to 0 and then write
2145          * the right values in the bus reset tasklet.
2146          */
2147
2148         if (config_rom) {
2149                 ohci->next_config_rom =
2150                         dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2151                                            &ohci->next_config_rom_bus,
2152                                            GFP_KERNEL);
2153                 if (ohci->next_config_rom == NULL)
2154                         return -ENOMEM;
2155
2156                 copy_config_rom(ohci->next_config_rom, config_rom, length);
2157         } else {
2158                 /*
2159                  * In the suspend case, config_rom is NULL, which
2160                  * means that we just reuse the old config rom.
2161                  */
2162                 ohci->next_config_rom = ohci->config_rom;
2163                 ohci->next_config_rom_bus = ohci->config_rom_bus;
2164         }
2165
2166         ohci->next_header = ohci->next_config_rom[0];
2167         ohci->next_config_rom[0] = 0;
2168         reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
2169         reg_write(ohci, OHCI1394_BusOptions,
2170                   be32_to_cpu(ohci->next_config_rom[2]));
2171         reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2172
2173         reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
2174
2175         if (!(ohci->quirks & QUIRK_NO_MSI))
2176                 pci_enable_msi(dev);
2177         if (request_irq(dev->irq, irq_handler,
2178                         pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED,
2179                         ohci_driver_name, ohci)) {
2180                 fw_error("Failed to allocate interrupt %d.\n", dev->irq);
2181                 pci_disable_msi(dev);
2182
2183                 if (config_rom) {
2184                         dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2185                                           ohci->next_config_rom,
2186                                           ohci->next_config_rom_bus);
2187                         ohci->next_config_rom = NULL;
2188                 }
2189                 return -EIO;
2190         }
2191
2192         irqs =  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
2193                 OHCI1394_RQPkt | OHCI1394_RSPkt |
2194                 OHCI1394_isochTx | OHCI1394_isochRx |
2195                 OHCI1394_postedWriteErr |
2196                 OHCI1394_selfIDComplete |
2197                 OHCI1394_regAccessFail |
2198                 OHCI1394_cycle64Seconds |
2199                 OHCI1394_cycleInconsistent |
2200                 OHCI1394_unrecoverableError |
2201                 OHCI1394_cycleTooLong |
2202                 OHCI1394_masterIntEnable;
2203         if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
2204                 irqs |= OHCI1394_busReset;
2205         reg_write(ohci, OHCI1394_IntMaskSet, irqs);
2206
2207         reg_write(ohci, OHCI1394_HCControlSet,
2208                   OHCI1394_HCControl_linkEnable |
2209                   OHCI1394_HCControl_BIBimageValid);
2210
2211         reg_write(ohci, OHCI1394_LinkControlSet,
2212                   OHCI1394_LinkControl_rcvSelfID |
2213                   OHCI1394_LinkControl_rcvPhyPkt);
2214
2215         ar_context_run(&ohci->ar_request_ctx);
2216         ar_context_run(&ohci->ar_response_ctx);
2217
2218         flush_writes(ohci);
2219
2220         /* We are ready to go, reset bus to finish initialization. */
2221         fw_schedule_bus_reset(&ohci->card, false, true);
2222
2223         return 0;
2224 }
2225
2226 static int ohci_set_config_rom(struct fw_card *card,
2227                                const __be32 *config_rom, size_t length)
2228 {
2229         struct fw_ohci *ohci;
2230         unsigned long flags;
2231         __be32 *next_config_rom;
2232         dma_addr_t uninitialized_var(next_config_rom_bus);
2233
2234         ohci = fw_ohci(card);
2235
2236         /*
2237          * When the OHCI controller is enabled, the config rom update
2238          * mechanism is a bit tricky, but easy enough to use.  See
2239          * section 5.5.6 in the OHCI specification.
2240          *
2241          * The OHCI controller caches the new config rom address in a
2242          * shadow register (ConfigROMmapNext) and needs a bus reset
2243          * for the changes to take place.  When the bus reset is
2244          * detected, the controller loads the new values for the
2245          * ConfigRomHeader and BusOptions registers from the specified
2246          * config rom and loads ConfigROMmap from the ConfigROMmapNext
2247          * shadow register. All automatically and atomically.
2248          *
2249          * Now, there's a twist to this story.  The automatic load of
2250          * ConfigRomHeader and BusOptions doesn't honor the
2251          * noByteSwapData bit, so with a be32 config rom, the
2252          * controller will load be32 values in to these registers
2253          * during the atomic update, even on litte endian
2254          * architectures.  The workaround we use is to put a 0 in the
2255          * header quadlet; 0 is endian agnostic and means that the
2256          * config rom isn't ready yet.  In the bus reset tasklet we
2257          * then set up the real values for the two registers.
2258          *
2259          * We use ohci->lock to avoid racing with the code that sets
2260          * ohci->next_config_rom to NULL (see bus_reset_tasklet).
2261          */
2262
2263         next_config_rom =
2264                 dma_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2265                                    &next_config_rom_bus, GFP_KERNEL);
2266         if (next_config_rom == NULL)
2267                 return -ENOMEM;
2268
2269         spin_lock_irqsave(&ohci->lock, flags);
2270
2271         /*
2272          * If there is not an already pending config_rom update,
2273          * push our new allocation into the ohci->next_config_rom
2274          * and then mark the local variable as null so that we
2275          * won't deallocate the new buffer.
2276          *
2277          * OTOH, if there is a pending config_rom update, just
2278          * use that buffer with the new config_rom data, and
2279          * let this routine free the unused DMA allocation.
2280          */
2281
2282         if (ohci->next_config_rom == NULL) {
2283                 ohci->next_config_rom = next_config_rom;
2284                 ohci->next_config_rom_bus = next_config_rom_bus;
2285                 next_config_rom = NULL;
2286         }
2287
2288         copy_config_rom(ohci->next_config_rom, config_rom, length);
2289
2290         ohci->next_header = config_rom[0];
2291         ohci->next_config_rom[0] = 0;
2292
2293         reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);
2294
2295         spin_unlock_irqrestore(&ohci->lock, flags);
2296
2297         /* If we didn't use the DMA allocation, delete it. */
2298         if (next_config_rom != NULL)
2299                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
2300                                   next_config_rom, next_config_rom_bus);
2301
2302         /*
2303          * Now initiate a bus reset to have the changes take
2304          * effect. We clean up the old config rom memory and DMA
2305          * mappings in the bus reset tasklet, since the OHCI
2306          * controller could need to access it before the bus reset
2307          * takes effect.
2308          */
2309
2310         fw_schedule_bus_reset(&ohci->card, true, true);
2311
2312         return 0;
2313 }
2314
2315 static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
2316 {
2317         struct fw_ohci *ohci = fw_ohci(card);
2318
2319         at_context_transmit(&ohci->at_request_ctx, packet);
2320 }
2321
2322 static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
2323 {
2324         struct fw_ohci *ohci = fw_ohci(card);
2325
2326         at_context_transmit(&ohci->at_response_ctx, packet);
2327 }
2328
2329 static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
2330 {
2331         struct fw_ohci *ohci = fw_ohci(card);
2332         struct context *ctx = &ohci->at_request_ctx;
2333         struct driver_data *driver_data = packet->driver_data;
2334         int ret = -ENOENT;
2335
2336         tasklet_disable(&ctx->tasklet);
2337
2338         if (packet->ack != 0)
2339                 goto out;
2340
2341         if (packet->payload_mapped)
2342                 dma_unmap_single(ohci->card.device, packet->payload_bus,
2343                                  packet->payload_length, DMA_TO_DEVICE);
2344
2345         log_ar_at_event('T', packet->speed, packet->header, 0x20);
2346         driver_data->packet = NULL;
2347         packet->ack = RCODE_CANCELLED;
2348         packet->callback(packet, &ohci->card, packet->ack);
2349         ret = 0;
2350  out:
2351         tasklet_enable(&ctx->tasklet);
2352
2353         return ret;
2354 }
2355
2356 static int ohci_enable_phys_dma(struct fw_card *card,
2357                                 int node_id, int generation)
2358 {
2359 #ifdef CONFIG_FIREWIRE_OHCI_REMOTE_DMA
2360         return 0;
2361 #else
2362         struct fw_ohci *ohci = fw_ohci(card);
2363         unsigned long flags;
2364         int n, ret = 0;
2365
2366         /*
2367          * FIXME:  Make sure this bitmask is cleared when we clear the busReset
2368          * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
2369          */
2370
2371         spin_lock_irqsave(&ohci->lock, flags);
2372
2373         if (ohci->generation != generation) {
2374                 ret = -ESTALE;
2375                 goto out;
2376         }
2377
2378         /*
2379          * Note, if the node ID contains a non-local bus ID, physical DMA is
2380          * enabled for _all_ nodes on remote buses.
2381          */
2382
2383         n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
2384         if (n < 32)
2385                 reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
2386         else
2387                 reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));
2388
2389         flush_writes(ohci);
2390  out:
2391         spin_unlock_irqrestore(&ohci->lock, flags);
2392
2393         return ret;
2394 #endif /* CONFIG_FIREWIRE_OHCI_REMOTE_DMA */
2395 }
2396
2397 static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
2398 {
2399         struct fw_ohci *ohci = fw_ohci(card);
2400         unsigned long flags;
2401         u32 value;
2402
2403         switch (csr_offset) {
2404         case CSR_STATE_CLEAR:
2405         case CSR_STATE_SET:
2406                 if (ohci->is_root &&
2407                     (reg_read(ohci, OHCI1394_LinkControlSet) &
2408                      OHCI1394_LinkControl_cycleMaster))
2409                         value = CSR_STATE_BIT_CMSTR;
2410                 else
2411                         value = 0;
2412                 if (ohci->csr_state_setclear_abdicate)
2413                         value |= CSR_STATE_BIT_ABDICATE;
2414
2415                 return value;
2416
2417         case CSR_NODE_IDS:
2418                 return reg_read(ohci, OHCI1394_NodeID) << 16;
2419
2420         case CSR_CYCLE_TIME:
2421                 return get_cycle_time(ohci);
2422
2423         case CSR_BUS_TIME:
2424                 /*
2425                  * We might be called just after the cycle timer has wrapped
2426                  * around but just before the cycle64Seconds handler, so we
2427                  * better check here, too, if the bus time needs to be updated.
2428                  */
2429                 spin_lock_irqsave(&ohci->lock, flags);
2430                 value = update_bus_time(ohci);
2431                 spin_unlock_irqrestore(&ohci->lock, flags);
2432                 return value;
2433
2434         case CSR_BUSY_TIMEOUT:
2435                 value = reg_read(ohci, OHCI1394_ATRetries);
2436                 return (value >> 4) & 0x0ffff00f;
2437
2438         case CSR_PRIORITY_BUDGET:
2439                 return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
2440                         (ohci->pri_req_max << 8);
2441
2442         default:
2443                 WARN_ON(1);
2444                 return 0;
2445         }
2446 }
2447
2448 static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
2449 {
2450         struct fw_ohci *ohci = fw_ohci(card);
2451         unsigned long flags;
2452
2453         switch (csr_offset) {
2454         case CSR_STATE_CLEAR:
2455                 if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2456                         reg_write(ohci, OHCI1394_LinkControlClear,
2457                                   OHCI1394_LinkControl_cycleMaster);
2458                         flush_writes(ohci);
2459                 }
2460                 if (value & CSR_STATE_BIT_ABDICATE)
2461                         ohci->csr_state_setclear_abdicate = false;
2462                 break;
2463
2464         case CSR_STATE_SET:
2465                 if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
2466                         reg_write(ohci, OHCI1394_LinkControlSet,
2467                                   OHCI1394_LinkControl_cycleMaster);
2468                         flush_writes(ohci);
2469                 }
2470                 if (value & CSR_STATE_BIT_ABDICATE)
2471                         ohci->csr_state_setclear_abdicate = true;
2472                 break;
2473
2474         case CSR_NODE_IDS:
2475                 reg_write(ohci, OHCI1394_NodeID, value >> 16);
2476                 flush_writes(ohci);
2477                 break;
2478
2479         case CSR_CYCLE_TIME:
2480                 reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
2481                 reg_write(ohci, OHCI1394_IntEventSet,
2482                           OHCI1394_cycleInconsistent);
2483                 flush_writes(ohci);
2484                 break;
2485
2486         case CSR_BUS_TIME:
2487                 spin_lock_irqsave(&ohci->lock, flags);
2488                 ohci->bus_time = (ohci->bus_time & 0x7f) | (value & ~0x7f);
2489                 spin_unlock_irqrestore(&ohci->lock, flags);
2490                 break;
2491
2492         case CSR_BUSY_TIMEOUT:
2493                 value = (value & 0xf) | ((value & 0xf) << 4) |
2494                         ((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
2495                 reg_write(ohci, OHCI1394_ATRetries, value);
2496                 flush_writes(ohci);
2497                 break;
2498
2499         case CSR_PRIORITY_BUDGET:
2500                 reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
2501                 flush_writes(ohci);
2502                 break;
2503
2504         default:
2505                 WARN_ON(1);
2506                 break;
2507         }
2508 }
2509
2510 static void copy_iso_headers(struct iso_context *ctx, void *p)
2511 {
2512         int i = ctx->header_length;
2513
2514         if (i + ctx->base.header_size > PAGE_SIZE)
2515                 return;
2516
2517         /*
2518          * The iso header is byteswapped to little endian by
2519          * the controller, but the remaining header quadlets
2520          * are big endian.  We want to present all the headers
2521          * as big endian, so we have to swap the first quadlet.
2522          */
2523         if (ctx->base.header_size > 0)
2524                 *(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
2525         if (ctx->base.header_size > 4)
2526                 *(u32 *) (ctx->header + i + 4) = __swab32(*(u32 *) p);
2527         if (ctx->base.header_size > 8)
2528                 memcpy(ctx->header + i + 8, p + 8, ctx->base.header_size - 8);
2529         ctx->header_length += ctx->base.header_size;
2530 }
2531
2532 static int handle_ir_packet_per_buffer(struct context *context,
2533                                        struct descriptor *d,
2534                                        struct descriptor *last)
2535 {
2536         struct iso_context *ctx =
2537                 container_of(context, struct iso_context, context);
2538         struct descriptor *pd;
2539         __le32 *ir_header;
2540         void *p;
2541
2542         for (pd = d; pd <= last; pd++)
2543                 if (pd->transfer_status)
2544                         break;
2545         if (pd > last)
2546                 /* Descriptor(s) not done yet, stop iteration */
2547                 return 0;
2548
2549         p = last + 1;
2550         copy_iso_headers(ctx, p);
2551
2552         if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2553                 ir_header = (__le32 *) p;
2554                 ctx->base.callback.sc(&ctx->base,
2555                                       le32_to_cpu(ir_header[0]) & 0xffff,
2556                                       ctx->header_length, ctx->header,
2557                                       ctx->base.callback_data);
2558                 ctx->header_length = 0;
2559         }
2560
2561         return 1;
2562 }
2563
2564 /* d == last because each descriptor block is only a single descriptor. */
2565 static int handle_ir_buffer_fill(struct context *context,
2566                                  struct descriptor *d,
2567                                  struct descriptor *last)
2568 {
2569         struct iso_context *ctx =
2570                 container_of(context, struct iso_context, context);
2571
2572         if (!last->transfer_status)
2573                 /* Descriptor(s) not done yet, stop iteration */
2574                 return 0;
2575
2576         if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS)
2577                 ctx->base.callback.mc(&ctx->base,
2578                                       le32_to_cpu(last->data_address) +
2579                                       le16_to_cpu(last->req_count) -
2580                                       le16_to_cpu(last->res_count),
2581                                       ctx->base.callback_data);
2582
2583         return 1;
2584 }
2585
2586 static int handle_it_packet(struct context *context,
2587                             struct descriptor *d,
2588                             struct descriptor *last)
2589 {
2590         struct iso_context *ctx =
2591                 container_of(context, struct iso_context, context);
2592         int i;
2593         struct descriptor *pd;
2594
2595         for (pd = d; pd <= last; pd++)
2596                 if (pd->transfer_status)
2597                         break;
2598         if (pd > last)
2599                 /* Descriptor(s) not done yet, stop iteration */
2600                 return 0;
2601
2602         i = ctx->header_length;
2603         if (i + 4 < PAGE_SIZE) {
2604                 /* Present this value as big-endian to match the receive code */
2605                 *(__be32 *)(ctx->header + i) = cpu_to_be32(
2606                                 ((u32)le16_to_cpu(pd->transfer_status) << 16) |
2607                                 le16_to_cpu(pd->res_count));
2608                 ctx->header_length += 4;
2609         }
2610         if (le16_to_cpu(last->control) & DESCRIPTOR_IRQ_ALWAYS) {
2611                 ctx->base.callback.sc(&ctx->base, le16_to_cpu(last->res_count),
2612                                       ctx->header_length, ctx->header,
2613                                       ctx->base.callback_data);
2614                 ctx->header_length = 0;
2615         }
2616         return 1;
2617 }
2618
2619 static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
2620 {
2621         u32 hi = channels >> 32, lo = channels;
2622
2623         reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
2624         reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
2625         reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
2626         reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
2627         mmiowb();
2628         ohci->mc_channels = channels;
2629 }
2630
2631 static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
2632                                 int type, int channel, size_t header_size)
2633 {
2634         struct fw_ohci *ohci = fw_ohci(card);
2635         struct iso_context *uninitialized_var(ctx);
2636         descriptor_callback_t uninitialized_var(callback);
2637         u64 *uninitialized_var(channels);
2638         u32 *uninitialized_var(mask), uninitialized_var(regs);
2639         unsigned long flags;
2640         int index, ret = -EBUSY;
2641
2642         spin_lock_irqsave(&ohci->lock, flags);
2643
2644         switch (type) {
2645         case FW_ISO_CONTEXT_TRANSMIT:
2646                 mask     = &ohci->it_context_mask;
2647                 callback = handle_it_packet;
2648                 index    = ffs(*mask) - 1;
2649                 if (index >= 0) {
2650                         *mask &= ~(1 << index);
2651                         regs = OHCI1394_IsoXmitContextBase(index);
2652                         ctx  = &ohci->it_context_list[index];
2653                 }
2654                 break;
2655
2656         case FW_ISO_CONTEXT_RECEIVE:
2657                 channels = &ohci->ir_context_channels;
2658                 mask     = &ohci->ir_context_mask;
2659                 callback = handle_ir_packet_per_buffer;
2660                 index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
2661                 if (index >= 0) {
2662                         *channels &= ~(1ULL << channel);
2663                         *mask     &= ~(1 << index);
2664                         regs = OHCI1394_IsoRcvContextBase(index);
2665                         ctx  = &ohci->ir_context_list[index];
2666                 }
2667                 break;
2668
2669         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2670                 mask     = &ohci->ir_context_mask;
2671                 callback = handle_ir_buffer_fill;
2672                 index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
2673                 if (index >= 0) {
2674                         ohci->mc_allocated = true;
2675                         *mask &= ~(1 << index);
2676                         regs = OHCI1394_IsoRcvContextBase(index);
2677                         ctx  = &ohci->ir_context_list[index];
2678                 }
2679                 break;
2680
2681         default:
2682                 index = -1;
2683                 ret = -ENOSYS;
2684         }
2685
2686         spin_unlock_irqrestore(&ohci->lock, flags);
2687
2688         if (index < 0)
2689                 return ERR_PTR(ret);
2690
2691         memset(ctx, 0, sizeof(*ctx));
2692         ctx->header_length = 0;
2693         ctx->header = (void *) __get_free_page(GFP_KERNEL);
2694         if (ctx->header == NULL) {
2695                 ret = -ENOMEM;
2696                 goto out;
2697         }
2698         ret = context_init(&ctx->context, ohci, regs, callback);
2699         if (ret < 0)
2700                 goto out_with_header;
2701
2702         if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
2703                 set_multichannel_mask(ohci, 0);
2704
2705         return &ctx->base;
2706
2707  out_with_header:
2708         free_page((unsigned long)ctx->header);
2709  out:
2710         spin_lock_irqsave(&ohci->lock, flags);
2711
2712         switch (type) {
2713         case FW_ISO_CONTEXT_RECEIVE:
2714                 *channels |= 1ULL << channel;
2715                 break;
2716
2717         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2718                 ohci->mc_allocated = false;
2719                 break;
2720         }
2721         *mask |= 1 << index;
2722
2723         spin_unlock_irqrestore(&ohci->lock, flags);
2724
2725         return ERR_PTR(ret);
2726 }
2727
2728 static int ohci_start_iso(struct fw_iso_context *base,
2729                           s32 cycle, u32 sync, u32 tags)
2730 {
2731         struct iso_context *ctx = container_of(base, struct iso_context, base);
2732         struct fw_ohci *ohci = ctx->context.ohci;
2733         u32 control = IR_CONTEXT_ISOCH_HEADER, match;
2734         int index;
2735
2736         /* the controller cannot start without any queued packets */
2737         if (ctx->context.last->branch_address == 0)
2738                 return -ENODATA;
2739
2740         switch (ctx->base.type) {
2741         case FW_ISO_CONTEXT_TRANSMIT:
2742                 index = ctx - ohci->it_context_list;
2743                 match = 0;
2744                 if (cycle >= 0)
2745                         match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
2746                                 (cycle & 0x7fff) << 16;
2747
2748                 reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
2749                 reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
2750                 context_run(&ctx->context, match);
2751                 break;
2752
2753         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2754                 control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
2755                 /* fall through */
2756         case FW_ISO_CONTEXT_RECEIVE:
2757                 index = ctx - ohci->ir_context_list;
2758                 match = (tags << 28) | (sync << 8) | ctx->base.channel;
2759                 if (cycle >= 0) {
2760                         match |= (cycle & 0x07fff) << 12;
2761                         control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
2762                 }
2763
2764                 reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
2765                 reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
2766                 reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
2767                 context_run(&ctx->context, control);
2768
2769                 ctx->sync = sync;
2770                 ctx->tags = tags;
2771
2772                 break;
2773         }
2774
2775         return 0;
2776 }
2777
2778 static int ohci_stop_iso(struct fw_iso_context *base)
2779 {
2780         struct fw_ohci *ohci = fw_ohci(base->card);
2781         struct iso_context *ctx = container_of(base, struct iso_context, base);
2782         int index;
2783
2784         switch (ctx->base.type) {
2785         case FW_ISO_CONTEXT_TRANSMIT:
2786                 index = ctx - ohci->it_context_list;
2787                 reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
2788                 break;
2789
2790         case FW_ISO_CONTEXT_RECEIVE:
2791         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2792                 index = ctx - ohci->ir_context_list;
2793                 reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
2794                 break;
2795         }
2796         flush_writes(ohci);
2797         context_stop(&ctx->context);
2798         tasklet_kill(&ctx->context.tasklet);
2799
2800         return 0;
2801 }
2802
2803 static void ohci_free_iso_context(struct fw_iso_context *base)
2804 {
2805         struct fw_ohci *ohci = fw_ohci(base->card);
2806         struct iso_context *ctx = container_of(base, struct iso_context, base);
2807         unsigned long flags;
2808         int index;
2809
2810         ohci_stop_iso(base);
2811         context_release(&ctx->context);
2812         free_page((unsigned long)ctx->header);
2813
2814         spin_lock_irqsave(&ohci->lock, flags);
2815
2816         switch (base->type) {
2817         case FW_ISO_CONTEXT_TRANSMIT:
2818                 index = ctx - ohci->it_context_list;
2819                 ohci->it_context_mask |= 1 << index;
2820                 break;
2821
2822         case FW_ISO_CONTEXT_RECEIVE:
2823                 index = ctx - ohci->ir_context_list;
2824                 ohci->ir_context_mask |= 1 << index;
2825                 ohci->ir_context_channels |= 1ULL << base->channel;
2826                 break;
2827
2828         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2829                 index = ctx - ohci->ir_context_list;
2830                 ohci->ir_context_mask |= 1 << index;
2831                 ohci->ir_context_channels |= ohci->mc_channels;
2832                 ohci->mc_channels = 0;
2833                 ohci->mc_allocated = false;
2834                 break;
2835         }
2836
2837         spin_unlock_irqrestore(&ohci->lock, flags);
2838 }
2839
2840 static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
2841 {
2842         struct fw_ohci *ohci = fw_ohci(base->card);
2843         unsigned long flags;
2844         int ret;
2845
2846         switch (base->type) {
2847         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
2848
2849                 spin_lock_irqsave(&ohci->lock, flags);
2850
2851                 /* Don't allow multichannel to grab other contexts' channels. */
2852                 if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
2853                         *channels = ohci->ir_context_channels;
2854                         ret = -EBUSY;
2855                 } else {
2856                         set_multichannel_mask(ohci, *channels);
2857                         ret = 0;
2858                 }
2859
2860                 spin_unlock_irqrestore(&ohci->lock, flags);
2861
2862                 break;
2863         default:
2864                 ret = -EINVAL;
2865         }
2866
2867         return ret;
2868 }
2869
2870 #ifdef CONFIG_PM
2871 static void ohci_resume_iso_dma(struct fw_ohci *ohci)
2872 {
2873         int i;
2874         struct iso_context *ctx;
2875
2876         for (i = 0 ; i < ohci->n_ir ; i++) {
2877                 ctx = &ohci->ir_context_list[i];
2878                 if (ctx->context.running)
2879                         ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
2880         }
2881
2882         for (i = 0 ; i < ohci->n_it ; i++) {
2883                 ctx = &ohci->it_context_list[i];
2884                 if (ctx->context.running)
2885                         ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
2886         }
2887 }
2888 #endif
2889
2890 static int queue_iso_transmit(struct iso_context *ctx,
2891                               struct fw_iso_packet *packet,
2892                               struct fw_iso_buffer *buffer,
2893                               unsigned long payload)
2894 {
2895         struct descriptor *d, *last, *pd;
2896         struct fw_iso_packet *p;
2897         __le32 *header;
2898         dma_addr_t d_bus, page_bus;
2899         u32 z, header_z, payload_z, irq;
2900         u32 payload_index, payload_end_index, next_page_index;
2901         int page, end_page, i, length, offset;
2902
2903         p = packet;
2904         payload_index = payload;
2905
2906         if (p->skip)
2907                 z = 1;
2908         else
2909                 z = 2;
2910         if (p->header_length > 0)
2911                 z++;
2912
2913         /* Determine the first page the payload isn't contained in. */
2914         end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
2915         if (p->payload_length > 0)
2916                 payload_z = end_page - (payload_index >> PAGE_SHIFT);
2917         else
2918                 payload_z = 0;
2919
2920         z += payload_z;
2921
2922         /* Get header size in number of descriptors. */
2923         header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));
2924
2925         d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
2926         if (d == NULL)
2927                 return -ENOMEM;
2928
2929         if (!p->skip) {
2930                 d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
2931                 d[0].req_count = cpu_to_le16(8);
2932                 /*
2933                  * Link the skip address to this descriptor itself.  This causes
2934                  * a context to skip a cycle whenever lost cycles or FIFO
2935                  * overruns occur, without dropping the data.  The application
2936                  * should then decide whether this is an error condition or not.
2937                  * FIXME:  Make the context's cycle-lost behaviour configurable?
2938                  */
2939                 d[0].branch_address = cpu_to_le32(d_bus | z);
2940
2941                 header = (__le32 *) &d[1];
2942                 header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
2943                                         IT_HEADER_TAG(p->tag) |
2944                                         IT_HEADER_TCODE(TCODE_STREAM_DATA) |
2945                                         IT_HEADER_CHANNEL(ctx->base.channel) |
2946                                         IT_HEADER_SPEED(ctx->base.speed));
2947                 header[1] =
2948                         cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
2949                                                           p->payload_length));
2950         }
2951
2952         if (p->header_length > 0) {
2953                 d[2].req_count    = cpu_to_le16(p->header_length);
2954                 d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
2955                 memcpy(&d[z], p->header, p->header_length);
2956         }
2957
2958         pd = d + z - payload_z;
2959         payload_end_index = payload_index + p->payload_length;
2960         for (i = 0; i < payload_z; i++) {
2961                 page               = payload_index >> PAGE_SHIFT;
2962                 offset             = payload_index & ~PAGE_MASK;
2963                 next_page_index    = (page + 1) << PAGE_SHIFT;
2964                 length             =
2965                         min(next_page_index, payload_end_index) - payload_index;
2966                 pd[i].req_count    = cpu_to_le16(length);
2967
2968                 page_bus = page_private(buffer->pages[page]);
2969                 pd[i].data_address = cpu_to_le32(page_bus + offset);
2970
2971                 payload_index += length;
2972         }
2973
2974         if (p->interrupt)
2975                 irq = DESCRIPTOR_IRQ_ALWAYS;
2976         else
2977                 irq = DESCRIPTOR_NO_IRQ;
2978
2979         last = z == 2 ? d : d + z - 1;
2980         last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
2981                                      DESCRIPTOR_STATUS |
2982                                      DESCRIPTOR_BRANCH_ALWAYS |
2983                                      irq);
2984
2985         context_append(&ctx->context, d, z, header_z);
2986
2987         return 0;
2988 }
2989
2990 static int queue_iso_packet_per_buffer(struct iso_context *ctx,
2991                                        struct fw_iso_packet *packet,
2992                                        struct fw_iso_buffer *buffer,
2993                                        unsigned long payload)
2994 {
2995         struct descriptor *d, *pd;
2996         dma_addr_t d_bus, page_bus;
2997         u32 z, header_z, rest;
2998         int i, j, length;
2999         int page, offset, packet_count, header_size, payload_per_buffer;
3000
3001         /*
3002          * The OHCI controller puts the isochronous header and trailer in the
3003          * buffer, so we need at least 8 bytes.
3004          */
3005         packet_count = packet->header_length / ctx->base.header_size;
3006         header_size  = max(ctx->base.header_size, (size_t)8);
3007
3008         /* Get header size in number of descriptors. */
3009         header_z = DIV_ROUND_UP(header_size, sizeof(*d));
3010         page     = payload >> PAGE_SHIFT;
3011         offset   = payload & ~PAGE_MASK;
3012         payload_per_buffer = packet->payload_length / packet_count;
3013
3014         for (i = 0; i < packet_count; i++) {
3015                 /* d points to the header descriptor */
3016                 z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
3017                 d = context_get_descriptors(&ctx->context,
3018                                 z + header_z, &d_bus);
3019                 if (d == NULL)
3020                         return -ENOMEM;
3021
3022                 d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
3023                                               DESCRIPTOR_INPUT_MORE);
3024                 if (packet->skip && i == 0)
3025                         d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3026                 d->req_count    = cpu_to_le16(header_size);
3027                 d->res_count    = d->req_count;
3028                 d->transfer_status = 0;
3029                 d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
3030
3031                 rest = payload_per_buffer;
3032                 pd = d;
3033                 for (j = 1; j < z; j++) {
3034                         pd++;
3035                         pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3036                                                   DESCRIPTOR_INPUT_MORE);
3037
3038                         if (offset + rest < PAGE_SIZE)
3039                                 length = rest;
3040                         else
3041                                 length = PAGE_SIZE - offset;
3042                         pd->req_count = cpu_to_le16(length);
3043                         pd->res_count = pd->req_count;
3044                         pd->transfer_status = 0;
3045
3046                         page_bus = page_private(buffer->pages[page]);
3047                         pd->data_address = cpu_to_le32(page_bus + offset);
3048
3049                         offset = (offset + length) & ~PAGE_MASK;
3050                         rest -= length;
3051                         if (offset == 0)
3052                                 page++;
3053                 }
3054                 pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
3055                                           DESCRIPTOR_INPUT_LAST |
3056                                           DESCRIPTOR_BRANCH_ALWAYS);
3057                 if (packet->interrupt && i == packet_count - 1)
3058                         pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3059
3060                 context_append(&ctx->context, d, z, header_z);
3061         }
3062
3063         return 0;
3064 }
3065
3066 static int queue_iso_buffer_fill(struct iso_context *ctx,
3067                                  struct fw_iso_packet *packet,
3068                                  struct fw_iso_buffer *buffer,
3069                                  unsigned long payload)
3070 {
3071         struct descriptor *d;
3072         dma_addr_t d_bus, page_bus;
3073         int page, offset, rest, z, i, length;
3074
3075         page   = payload >> PAGE_SHIFT;
3076         offset = payload & ~PAGE_MASK;
3077         rest   = packet->payload_length;
3078
3079         /* We need one descriptor for each page in the buffer. */
3080         z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);
3081
3082         if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
3083                 return -EFAULT;
3084
3085         for (i = 0; i < z; i++) {
3086                 d = context_get_descriptors(&ctx->context, 1, &d_bus);
3087                 if (d == NULL)
3088                         return -ENOMEM;
3089
3090                 d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
3091                                          DESCRIPTOR_BRANCH_ALWAYS);
3092                 if (packet->skip && i == 0)
3093                         d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
3094                 if (packet->interrupt && i == z - 1)
3095                         d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
3096
3097                 if (offset + rest < PAGE_SIZE)
3098                         length = rest;
3099                 else
3100                         length = PAGE_SIZE - offset;
3101                 d->req_count = cpu_to_le16(length);
3102                 d->res_count = d->req_count;
3103                 d->transfer_status = 0;
3104
3105                 page_bus = page_private(buffer->pages[page]);
3106                 d->data_address = cpu_to_le32(page_bus + offset);
3107
3108                 rest -= length;
3109                 offset = 0;
3110                 page++;
3111
3112                 context_append(&ctx->context, d, 1, 0);
3113         }
3114
3115         return 0;
3116 }
3117
3118 static int ohci_queue_iso(struct fw_iso_context *base,
3119                           struct fw_iso_packet *packet,
3120                           struct fw_iso_buffer *buffer,
3121                           unsigned long payload)
3122 {
3123         struct iso_context *ctx = container_of(base, struct iso_context, base);
3124         unsigned long flags;
3125         int ret = -ENOSYS;
3126
3127         spin_lock_irqsave(&ctx->context.ohci->lock, flags);
3128         switch (base->type) {
3129         case FW_ISO_CONTEXT_TRANSMIT:
3130                 ret = queue_iso_transmit(ctx, packet, buffer, payload);
3131                 break;
3132         case FW_ISO_CONTEXT_RECEIVE:
3133                 ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
3134                 break;
3135         case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
3136                 ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
3137                 break;
3138         }
3139         spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);
3140
3141         return ret;
3142 }
3143
3144 static void ohci_flush_queue_iso(struct fw_iso_context *base)
3145 {
3146         struct context *ctx =
3147                         &container_of(base, struct iso_context, base)->context;
3148
3149         reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
3150 }
3151
3152 static const struct fw_card_driver ohci_driver = {
3153         .enable                 = ohci_enable,
3154         .read_phy_reg           = ohci_read_phy_reg,
3155         .update_phy_reg         = ohci_update_phy_reg,
3156         .set_config_rom         = ohci_set_config_rom,
3157         .send_request           = ohci_send_request,
3158         .send_response          = ohci_send_response,
3159         .cancel_packet          = ohci_cancel_packet,
3160         .enable_phys_dma        = ohci_enable_phys_dma,
3161         .read_csr               = ohci_read_csr,
3162         .write_csr              = ohci_write_csr,
3163
3164         .allocate_iso_context   = ohci_allocate_iso_context,
3165         .free_iso_context       = ohci_free_iso_context,
3166         .set_iso_channels       = ohci_set_iso_channels,
3167         .queue_iso              = ohci_queue_iso,
3168         .flush_queue_iso        = ohci_flush_queue_iso,
3169         .start_iso              = ohci_start_iso,
3170         .stop_iso               = ohci_stop_iso,
3171 };
3172
3173 #ifdef CONFIG_PPC_PMAC
3174 static void pmac_ohci_on(struct pci_dev *dev)
3175 {
3176         if (machine_is(powermac)) {
3177                 struct device_node *ofn = pci_device_to_OF_node(dev);
3178
3179                 if (ofn) {
3180                         pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
3181                         pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
3182                 }
3183         }
3184 }
3185
3186 static void pmac_ohci_off(struct pci_dev *dev)
3187 {
3188         if (machine_is(powermac)) {
3189                 struct device_node *ofn = pci_device_to_OF_node(dev);
3190
3191                 if (ofn) {
3192                         pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
3193                         pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
3194                 }
3195         }
3196 }
3197 #else
3198 static inline void pmac_ohci_on(struct pci_dev *dev) {}
3199 static inline void pmac_ohci_off(struct pci_dev *dev) {}
3200 #endif /* CONFIG_PPC_PMAC */
3201
3202 static int __devinit pci_probe(struct pci_dev *dev,
3203                                const struct pci_device_id *ent)
3204 {
3205         struct fw_ohci *ohci;
3206         u32 bus_options, max_receive, link_speed, version;
3207         u64 guid;
3208         int i, err;
3209         size_t size;
3210
3211         if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
3212                 dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
3213                 return -ENOSYS;
3214         }
3215
3216         ohci = kzalloc(sizeof(*ohci), GFP_KERNEL);
3217         if (ohci == NULL) {
3218                 err = -ENOMEM;
3219                 goto fail;
3220         }
3221
3222         fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
3223
3224         pmac_ohci_on(dev);
3225
3226         err = pci_enable_device(dev);
3227         if (err) {
3228                 fw_error("Failed to enable OHCI hardware\n");
3229                 goto fail_free;
3230         }
3231
3232         pci_set_master(dev);
3233         pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
3234         pci_set_drvdata(dev, ohci);
3235
3236         spin_lock_init(&ohci->lock);
3237         mutex_init(&ohci->phy_reg_mutex);
3238
3239         tasklet_init(&ohci->bus_reset_tasklet,
3240                      bus_reset_tasklet, (unsigned long)ohci);
3241
3242         err = pci_request_region(dev, 0, ohci_driver_name);
3243         if (err) {
3244                 fw_error("MMIO resource unavailable\n");
3245                 goto fail_disable;
3246         }
3247
3248         ohci->registers = pci_iomap(dev, 0, OHCI1394_REGISTER_SIZE);
3249         if (ohci->registers == NULL) {
3250                 fw_error("Failed to remap registers\n");
3251                 err = -ENXIO;
3252                 goto fail_iomem;
3253         }
3254
3255         for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
3256                 if ((ohci_quirks[i].vendor == dev->vendor) &&
3257                     (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
3258                      ohci_quirks[i].device == dev->device) &&
3259                     (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
3260                      ohci_quirks[i].revision >= dev->revision)) {
3261                         ohci->quirks = ohci_quirks[i].flags;
3262                         break;
3263                 }
3264         if (param_quirks)
3265                 ohci->quirks = param_quirks;
3266
3267         /*
3268          * Because dma_alloc_coherent() allocates at least one page,
3269          * we save space by using a common buffer for the AR request/
3270          * response descriptors and the self IDs buffer.
3271          */
3272         BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
3273         BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
3274         ohci->misc_buffer = dma_alloc_coherent(ohci->card.device,
3275                                                PAGE_SIZE,
3276                                                &ohci->misc_buffer_bus,
3277                                                GFP_KERNEL);
3278         if (!ohci->misc_buffer) {
3279                 err = -ENOMEM;
3280                 goto fail_iounmap;
3281         }
3282
3283         err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
3284                               OHCI1394_AsReqRcvContextControlSet);
3285         if (err < 0)
3286                 goto fail_misc_buf;
3287
3288         err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
3289                               OHCI1394_AsRspRcvContextControlSet);
3290         if (err < 0)
3291                 goto fail_arreq_ctx;
3292
3293         err = context_init(&ohci->at_request_ctx, ohci,
3294                            OHCI1394_AsReqTrContextControlSet, handle_at_packet);
3295         if (err < 0)
3296                 goto fail_arrsp_ctx;
3297
3298         err = context_init(&ohci->at_response_ctx, ohci,
3299                            OHCI1394_AsRspTrContextControlSet, handle_at_packet);
3300         if (err < 0)
3301                 goto fail_atreq_ctx;
3302
3303         reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
3304         ohci->ir_context_channels = ~0ULL;
3305         ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
3306         reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
3307         ohci->ir_context_mask = ohci->ir_context_support;
3308         ohci->n_ir = hweight32(ohci->ir_context_mask);
3309         size = sizeof(struct iso_context) * ohci->n_ir;
3310         ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
3311
3312         reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
3313         ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
3314         reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
3315         ohci->it_context_mask = ohci->it_context_support;
3316         ohci->n_it = hweight32(ohci->it_context_mask);
3317         size = sizeof(struct iso_context) * ohci->n_it;
3318         ohci->it_context_list = kzalloc(size, GFP_KERNEL);
3319
3320         if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
3321                 err = -ENOMEM;
3322                 goto fail_contexts;
3323         }
3324
3325         ohci->self_id_cpu = ohci->misc_buffer     + PAGE_SIZE/2;
3326         ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;
3327
3328         bus_options = reg_read(ohci, OHCI1394_BusOptions);
3329         max_receive = (bus_options >> 12) & 0xf;
3330         link_speed = bus_options & 0x7;
3331         guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
3332                 reg_read(ohci, OHCI1394_GUIDLo);
3333
3334         err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
3335         if (err)
3336                 goto fail_contexts;
3337
3338         version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
3339         fw_notify("Added fw-ohci device %s, OHCI v%x.%x, "
3340                   "%d IR + %d IT contexts, quirks 0x%x\n",
3341                   dev_name(&dev->dev), version >> 16, version & 0xff,
3342                   ohci->n_ir, ohci->n_it, ohci->quirks);
3343
3344         return 0;
3345
3346  fail_contexts:
3347         kfree(ohci->ir_context_list);
3348         kfree(ohci->it_context_list);
3349         context_release(&ohci->at_response_ctx);
3350  fail_atreq_ctx:
3351         context_release(&ohci->at_request_ctx);
3352  fail_arrsp_ctx:
3353         ar_context_release(&ohci->ar_response_ctx);
3354  fail_arreq_ctx:
3355         ar_context_release(&ohci->ar_request_ctx);
3356  fail_misc_buf:
3357         dma_free_coherent(ohci->card.device, PAGE_SIZE,
3358                           ohci->misc_buffer, ohci->misc_buffer_bus);
3359  fail_iounmap:
3360         pci_iounmap(dev, ohci->registers);
3361  fail_iomem:
3362         pci_release_region(dev, 0);
3363  fail_disable:
3364         pci_disable_device(dev);
3365  fail_free:
3366         kfree(ohci);
3367         pmac_ohci_off(dev);
3368  fail:
3369         if (err == -ENOMEM)
3370                 fw_error("Out of memory\n");
3371
3372         return err;
3373 }
3374
3375 static void pci_remove(struct pci_dev *dev)
3376 {
3377         struct fw_ohci *ohci;
3378
3379         ohci = pci_get_drvdata(dev);
3380         reg_write(ohci, OHCI1394_IntMaskClear, ~0);
3381         flush_writes(ohci);
3382         fw_core_remove_card(&ohci->card);
3383
3384         /*
3385          * FIXME: Fail all pending packets here, now that the upper
3386          * layers can't queue any more.
3387          */
3388
3389         software_reset(ohci);
3390         free_irq(dev->irq, ohci);
3391
3392         if (ohci->next_config_rom && ohci->next_config_rom != ohci->config_rom)
3393                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3394                                   ohci->next_config_rom, ohci->next_config_rom_bus);
3395         if (ohci->config_rom)
3396                 dma_free_coherent(ohci->card.device, CONFIG_ROM_SIZE,
3397                                   ohci->config_rom, ohci->config_rom_bus);
3398         ar_context_release(&ohci->ar_request_ctx);
3399         ar_context_release(&ohci->ar_response_ctx);
3400         dma_free_coherent(ohci->card.device, PAGE_SIZE,
3401                           ohci->misc_buffer, ohci->misc_buffer_bus);
3402         context_release(&ohci->at_request_ctx);
3403         context_release(&ohci->at_response_ctx);
3404         kfree(ohci->it_context_list);
3405         kfree(ohci->ir_context_list);
3406         pci_disable_msi(dev);
3407         pci_iounmap(dev, ohci->registers);
3408         pci_release_region(dev, 0);
3409         pci_disable_device(dev);
3410         kfree(ohci);
3411         pmac_ohci_off(dev);
3412
3413         fw_notify("Removed fw-ohci device.\n");
3414 }
3415
3416 #ifdef CONFIG_PM
3417 static int pci_suspend(struct pci_dev *dev, pm_message_t state)
3418 {
3419         struct fw_ohci *ohci = pci_get_drvdata(dev);
3420         int err;
3421
3422         software_reset(ohci);
3423         free_irq(dev->irq, ohci);
3424         pci_disable_msi(dev);
3425         err = pci_save_state(dev);
3426         if (err) {
3427                 fw_error("pci_save_state failed\n");
3428                 return err;
3429         }
3430         err = pci_set_power_state(dev, pci_choose_state(dev, state));
3431         if (err)
3432                 fw_error("pci_set_power_state failed with %d\n", err);
3433         pmac_ohci_off(dev);
3434
3435         return 0;
3436 }
3437
3438 static int pci_resume(struct pci_dev *dev)
3439 {
3440         struct fw_ohci *ohci = pci_get_drvdata(dev);
3441         int err;
3442
3443         pmac_ohci_on(dev);
3444         pci_set_power_state(dev, PCI_D0);
3445         pci_restore_state(dev);
3446         err = pci_enable_device(dev);
3447         if (err) {
3448                 fw_error("pci_enable_device failed\n");
3449                 return err;
3450         }
3451
3452         /* Some systems don't setup GUID register on resume from ram  */
3453         if (!reg_read(ohci, OHCI1394_GUIDLo) &&
3454                                         !reg_read(ohci, OHCI1394_GUIDHi)) {
3455                 reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
3456                 reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
3457         }
3458
3459         err = ohci_enable(&ohci->card, NULL, 0);
3460         if (err)
3461                 return err;
3462
3463         ohci_resume_iso_dma(ohci);
3464
3465         return 0;
3466 }
3467 #endif
3468
3469 static const struct pci_device_id pci_table[] = {
3470         { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
3471         { }
3472 };
3473
3474 MODULE_DEVICE_TABLE(pci, pci_table);
3475
3476 static struct pci_driver fw_ohci_pci_driver = {
3477         .name           = ohci_driver_name,
3478         .id_table       = pci_table,
3479         .probe          = pci_probe,
3480         .remove         = pci_remove,
3481 #ifdef CONFIG_PM
3482         .resume         = pci_resume,
3483         .suspend        = pci_suspend,
3484 #endif
3485 };
3486
3487 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
3488 MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
3489 MODULE_LICENSE("GPL");
3490
3491 /* Provide a module alias so root-on-sbp2 initrds don't break. */
3492 #ifndef CONFIG_IEEE1394_OHCI1394_MODULE
3493 MODULE_ALIAS("ohci1394");
3494 #endif
3495
3496 static int __init fw_ohci_init(void)
3497 {
3498         return pci_register_driver(&fw_ohci_pci_driver);
3499 }
3500
3501 static void __exit fw_ohci_cleanup(void)
3502 {
3503         pci_unregister_driver(&fw_ohci_pci_driver);
3504 }
3505
3506 module_init(fw_ohci_init);
3507 module_exit(fw_ohci_cleanup);