drivers/ieee1394/iso.c

   1 /*
   2  * IEEE 1394 for Linux
   3  *
   4  * kernel ISO transmission/reception
   5  *
   6  * Copyright (C) 2002 Maas Digital LLC
   7  *
   8  * This code is licensed under the GPL.  See the file COPYING in the root
   9  * directory of the kernel sources for details.
  10  */
  11
  12 #include <linux/pci.h>
  13 #include <linux/slab.h>
  14
  15 #include "hosts.h"
  16 #include "iso.h"
  17
  18 void hpsb_iso_stop(struct hpsb_iso *iso)
  19 {
  20         if (!(iso->flags & HPSB_ISO_DRIVER_STARTED))
  21                 return;
  22
  23         iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
  24                                   XMIT_STOP : RECV_STOP, 0);
  25         iso->flags &= ~HPSB_ISO_DRIVER_STARTED;
  26 }
  27
  28 void hpsb_iso_shutdown(struct hpsb_iso *iso)
  29 {
  30         if (iso->flags & HPSB_ISO_DRIVER_INIT) {
  31                 hpsb_iso_stop(iso);
  32                 iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
  33                                           XMIT_SHUTDOWN : RECV_SHUTDOWN, 0);
  34                 iso->flags &= ~HPSB_ISO_DRIVER_INIT;
  35         }
  36
  37         dma_region_free(&iso->data_buf);
  38         kfree(iso);
  39 }
  40
  41 static struct hpsb_iso *hpsb_iso_common_init(struct hpsb_host *host,
  42                                              enum hpsb_iso_type type,
  43                                              unsigned int data_buf_size,
  44                                              unsigned int buf_packets,
  45                                              int channel, int dma_mode,
  46                                              int irq_interval,
  47                                              void (*callback) (struct hpsb_iso
  48                                                                *))
  49 {
  50         struct hpsb_iso *iso;
  51         int dma_direction;
  52
  53         /* make sure driver supports the ISO API */
  54         if (!host->driver->isoctl) {
  55                 printk(KERN_INFO
  56                        "ieee1394: host driver '%s' does not support the rawiso API\n",
  57                        host->driver->name);
  58                 return NULL;
  59         }
  60
  61         /* sanitize parameters */
  62
  63         if (buf_packets < 2)
  64                 buf_packets = 2;
  65
  66         if ((dma_mode < HPSB_ISO_DMA_DEFAULT)
  67             || (dma_mode > HPSB_ISO_DMA_PACKET_PER_BUFFER))
  68                 dma_mode = HPSB_ISO_DMA_DEFAULT;
  69
  70         if ((irq_interval < 0) || (irq_interval > buf_packets / 4))
  71                 irq_interval = buf_packets / 4;
  72         if (irq_interval == 0)  /* really interrupt for each packet */
  73                 irq_interval = 1;
  74
  75         if (channel < -1 || channel >= 64)
  76                 return NULL;
  77
  78         /* channel = -1 is OK for multi-channel recv but not for xmit */
  79         if (type == HPSB_ISO_XMIT && channel < 0)
  80                 return NULL;
  81
  82         /* allocate and write the struct hpsb_iso */
  83
  84         iso =
  85             kmalloc(sizeof(*iso) +
  86                     buf_packets * sizeof(struct hpsb_iso_packet_info),
  87                     GFP_KERNEL);
  88         if (!iso)
  89                 return NULL;
  90
  91         iso->infos = (struct hpsb_iso_packet_info *)(iso + 1);
  92
  93         iso->type = type;
  94         iso->host = host;
  95         iso->hostdata = NULL;
  96         iso->callback = callback;
  97         init_waitqueue_head(&iso->waitq);
  98         iso->channel = channel;
  99         iso->irq_interval = irq_interval;
 100         iso->dma_mode = dma_mode;
 101         dma_region_init(&iso->data_buf);
 102         iso->buf_size = PAGE_ALIGN(data_buf_size);
 103         iso->buf_packets = buf_packets;
 104         iso->pkt_dma = 0;
 105         iso->first_packet = 0;
 106         spin_lock_init(&iso->lock);
 107
 108         if (iso->type == HPSB_ISO_XMIT) {
 109                 iso->n_ready_packets = iso->buf_packets;
 110                 dma_direction = PCI_DMA_TODEVICE;
 111         } else {
 112                 iso->n_ready_packets = 0;
 113                 dma_direction = PCI_DMA_FROMDEVICE;
 114         }
 115
 116         atomic_set(&iso->overflows, 0);
 117         iso->bytes_discarded = 0;
 118         iso->flags = 0;
 119         iso->prebuffer = 0;
 120
 121         /* allocate the packet buffer */
 122         if (dma_region_alloc
 123             (&iso->data_buf, iso->buf_size, host->pdev, dma_direction))
 124                 goto err;
 125
 126         return iso;
 127
 128       err:
 129         hpsb_iso_shutdown(iso);
 130         return NULL;
 131 }
 132
 133 int hpsb_iso_n_ready(struct hpsb_iso *iso)
 134 {
 135         unsigned long flags;
 136         int val;
 137
 138         spin_lock_irqsave(&iso->lock, flags);
 139         val = iso->n_ready_packets;
 140         spin_unlock_irqrestore(&iso->lock, flags);
 141
 142         return val;
 143 }
 144
 145 struct hpsb_iso *hpsb_iso_xmit_init(struct hpsb_host *host,
 146                                     unsigned int data_buf_size,
 147                                     unsigned int buf_packets,
 148                                     int channel,
 149                                     int speed,
 150                                     int irq_interval,
 151                                     void (*callback) (struct hpsb_iso *))
 152 {
 153         struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_XMIT,
 154                                                     data_buf_size, buf_packets,
 155                                                     channel,
 156                                                     HPSB_ISO_DMA_DEFAULT,
 157                                                     irq_interval, callback);
 158         if (!iso)
 159                 return NULL;
 160
 161         iso->speed = speed;
 162
 163         /* tell the driver to start working */
 164         if (host->driver->isoctl(iso, XMIT_INIT, 0))
 165                 goto err;
 166
 167         iso->flags |= HPSB_ISO_DRIVER_INIT;
 168         return iso;
 169
 170       err:
 171         hpsb_iso_shutdown(iso);
 172         return NULL;
 173 }
 174
 175 struct hpsb_iso *hpsb_iso_recv_init(struct hpsb_host *host,
 176                                     unsigned int data_buf_size,
 177                                     unsigned int buf_packets,
 178                                     int channel,
 179                                     int dma_mode,
 180                                     int irq_interval,
 181                                     void (*callback) (struct hpsb_iso *))
 182 {
 183         struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_RECV,
 184                                                     data_buf_size, buf_packets,
 185                                                     channel, dma_mode,
 186                                                     irq_interval, callback);
 187         if (!iso)
 188                 return NULL;
 189
 190         /* tell the driver to start working */
 191         if (host->driver->isoctl(iso, RECV_INIT, 0))
 192                 goto err;
 193
 194         iso->flags |= HPSB_ISO_DRIVER_INIT;
 195         return iso;
 196
 197       err:
 198         hpsb_iso_shutdown(iso);
 199         return NULL;
 200 }
 201
 202 int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel)
 203 {
 204         if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
 205                 return -EINVAL;
 206         return iso->host->driver->isoctl(iso, RECV_LISTEN_CHANNEL, channel);
 207 }
 208
 209 int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel)
 210 {
 211         if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
 212                 return -EINVAL;
 213         return iso->host->driver->isoctl(iso, RECV_UNLISTEN_CHANNEL, channel);
 214 }
 215
 216 int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask)
 217 {
 218         if (iso->type != HPSB_ISO_RECV || iso->channel != -1)
 219                 return -EINVAL;
 220         return iso->host->driver->isoctl(iso, RECV_SET_CHANNEL_MASK,
 221                                          (unsigned long)&mask);
 222 }
 223
 224 int hpsb_iso_recv_flush(struct hpsb_iso *iso)
 225 {
 226         if (iso->type != HPSB_ISO_RECV)
 227                 return -EINVAL;
 228         return iso->host->driver->isoctl(iso, RECV_FLUSH, 0);
 229 }
 230
 231 static int do_iso_xmit_start(struct hpsb_iso *iso, int cycle)
 232 {
 233         int retval = iso->host->driver->isoctl(iso, XMIT_START, cycle);
 234         if (retval)
 235                 return retval;
 236
 237         iso->flags |= HPSB_ISO_DRIVER_STARTED;
 238         return retval;
 239 }
 240
 241 int hpsb_iso_xmit_start(struct hpsb_iso *iso, int cycle, int prebuffer)
 242 {
 243         if (iso->type != HPSB_ISO_XMIT)
 244                 return -1;
 245
 246         if (iso->flags & HPSB_ISO_DRIVER_STARTED)
 247                 return 0;
 248
 249         if (cycle < -1)
 250                 cycle = -1;
 251         else if (cycle >= 8000)
 252                 cycle %= 8000;
 253
 254         iso->xmit_cycle = cycle;
 255
 256         if (prebuffer < 0)
 257                 prebuffer = iso->buf_packets - 1;
 258         else if (prebuffer == 0)
 259                 prebuffer = 1;
 260
 261         if (prebuffer >= iso->buf_packets)
 262                 prebuffer = iso->buf_packets - 1;
 263
 264         iso->prebuffer = prebuffer;
 265
 266         /* remember the starting cycle; DMA will commence from xmit_queue_packets()
 267            once enough packets have been buffered */
 268         iso->start_cycle = cycle;
 269
 270         return 0;
 271 }
 272
 273 int hpsb_iso_recv_start(struct hpsb_iso *iso, int cycle, int tag_mask, int sync)
 274 {
 275         int retval = 0;
 276         int isoctl_args[3];
 277
 278         if (iso->type != HPSB_ISO_RECV)
 279                 return -1;
 280
 281         if (iso->flags & HPSB_ISO_DRIVER_STARTED)
 282                 return 0;
 283
 284         if (cycle < -1)
 285                 cycle = -1;
 286         else if (cycle >= 8000)
 287                 cycle %= 8000;
 288
 289         isoctl_args[0] = cycle;
 290
 291         if (tag_mask < 0)
 292                 /* match all tags */
 293                 tag_mask = 0xF;
 294         isoctl_args[1] = tag_mask;
 295
 296         isoctl_args[2] = sync;
 297
 298         retval =
 299             iso->host->driver->isoctl(iso, RECV_START,
 300                                       (unsigned long)&isoctl_args[0]);
 301         if (retval)
 302                 return retval;
 303
 304         iso->flags |= HPSB_ISO_DRIVER_STARTED;
 305         return retval;
 306 }
 307
 308 /* check to make sure the user has not supplied bogus values of offset/len
 309    that would cause the kernel to access memory outside the buffer */
 310
 311 static int hpsb_iso_check_offset_len(struct hpsb_iso *iso,
 312                                      unsigned int offset, unsigned short len,
 313                                      unsigned int *out_offset,
 314                                      unsigned short *out_len)
 315 {
 316         if (offset >= iso->buf_size)
 317                 return -EFAULT;
 318
 319         /* make sure the packet does not go beyond the end of the buffer */
 320         if (offset + len > iso->buf_size)
 321                 return -EFAULT;
 322
 323         /* check for wrap-around */
 324         if (offset + len < offset)
 325                 return -EFAULT;
 326
 327         /* now we can trust 'offset' and 'length' */
 328         *out_offset = offset;
 329         *out_len = len;
 330
 331         return 0;
 332 }
 333
 334 int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len,
 335                                u8 tag, u8 sy)
 336 {
 337         struct hpsb_iso_packet_info *info;
 338         unsigned long flags;
 339         int rv;
 340
 341         if (iso->type != HPSB_ISO_XMIT)
 342                 return -EINVAL;
 343
 344         /* is there space in the buffer? */
 345         if (iso->n_ready_packets <= 0) {
 346                 return -EBUSY;
 347         }
 348
 349         info = &iso->infos[iso->first_packet];
 350
 351         /* check for bogus offset/length */
 352         if (hpsb_iso_check_offset_len
 353             (iso, offset, len, &info->offset, &info->len))
 354                 return -EFAULT;
 355
 356         info->tag = tag;
 357         info->sy = sy;
 358
 359         spin_lock_irqsave(&iso->lock, flags);
 360
 361         rv = iso->host->driver->isoctl(iso, XMIT_QUEUE, (unsigned long)info);
 362         if (rv)
 363                 goto out;
 364
 365         /* increment cursors */
 366         iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
 367         iso->xmit_cycle = (iso->xmit_cycle + 1) % 8000;
 368         iso->n_ready_packets--;
 369
 370         if (iso->prebuffer != 0) {
 371                 iso->prebuffer--;
 372                 if (iso->prebuffer <= 0) {
 373                         iso->prebuffer = 0;
 374                         rv = do_iso_xmit_start(iso, iso->start_cycle);
 375                 }
 376         }
 377
 378       out:
 379         spin_unlock_irqrestore(&iso->lock, flags);
 380         return rv;
 381 }
 382
 383 int hpsb_iso_xmit_sync(struct hpsb_iso *iso)
 384 {
 385         if (iso->type != HPSB_ISO_XMIT)
 386                 return -EINVAL;
 387
 388         return wait_event_interruptible(iso->waitq,
 389                                         hpsb_iso_n_ready(iso) ==
 390                                         iso->buf_packets);
 391 }
 392
 393 void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error)
 394 {
 395         unsigned long flags;
 396         spin_lock_irqsave(&iso->lock, flags);
 397
 398         /* predict the cycle of the next packet to be queued */
 399
 400         /* jump ahead by the number of packets that are already buffered */
 401         cycle += iso->buf_packets - iso->n_ready_packets;
 402         cycle %= 8000;
 403
 404         iso->xmit_cycle = cycle;
 405         iso->n_ready_packets++;
 406         iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
 407
 408         if (iso->n_ready_packets == iso->buf_packets || error != 0) {
 409                 /* the buffer has run empty! */
 410                 atomic_inc(&iso->overflows);
 411         }
 412
 413         spin_unlock_irqrestore(&iso->lock, flags);
 414 }
 415
 416 void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
 417                               u16 total_len, u16 cycle, u8 channel, u8 tag,
 418                               u8 sy)
 419 {
 420         unsigned long flags;
 421         spin_lock_irqsave(&iso->lock, flags);
 422
 423         if (iso->n_ready_packets == iso->buf_packets) {
 424                 /* overflow! */
 425                 atomic_inc(&iso->overflows);
 426                 /* Record size of this discarded packet */
 427                 iso->bytes_discarded += total_len;
 428         } else {
 429                 struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];
 430                 info->offset = offset;
 431                 info->len = len;
 432                 info->total_len = total_len;
 433                 info->cycle = cycle;
 434                 info->channel = channel;
 435                 info->tag = tag;
 436                 info->sy = sy;
 437
 438                 iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
 439                 iso->n_ready_packets++;
 440         }
 441
 442         spin_unlock_irqrestore(&iso->lock, flags);
 443 }
 444
 445 int hpsb_iso_recv_release_packets(struct hpsb_iso *iso, unsigned int n_packets)
 446 {
 447         unsigned long flags;
 448         unsigned int i;
 449         int rv = 0;
 450
 451         if (iso->type != HPSB_ISO_RECV)
 452                 return -1;
 453
 454         spin_lock_irqsave(&iso->lock, flags);
 455         for (i = 0; i < n_packets; i++) {
 456                 rv = iso->host->driver->isoctl(iso, RECV_RELEASE,
 457                                                (unsigned long)&iso->infos[iso->
 458                                                                           first_packet]);
 459                 if (rv)
 460                         break;
 461
 462                 iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
 463                 iso->n_ready_packets--;
 464
 465                 /* release memory from packets discarded when queue was full  */
 466                 if (iso->n_ready_packets == 0) {        /* Release only after all prior packets handled */
 467                         if (iso->bytes_discarded != 0) {
 468                                 struct hpsb_iso_packet_info inf;
 469                                 inf.total_len = iso->bytes_discarded;
 470                                 iso->host->driver->isoctl(iso, RECV_RELEASE,
 471                                                           (unsigned long)&inf);
 472                                 iso->bytes_discarded = 0;
 473                         }
 474                 }
 475         }
 476         spin_unlock_irqrestore(&iso->lock, flags);
 477         return rv;
 478 }
 479
 480 void hpsb_iso_wake(struct hpsb_iso *iso)
 481 {
 482         wake_up_interruptible(&iso->waitq);
 483
 484         if (iso->callback)
 485                 iso->callback(iso);
 486 }