drivers/net/arcnet/arcnet.c

   1 /*
   2  * Linux ARCnet driver - device-independent routines
   3  *
   4  * Written 1997 by David Woodhouse.
   5  * Written 1994-1999 by Avery Pennarun.
   6  * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
   7  * Derived from skeleton.c by Donald Becker.
   8  *
   9  * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
  10  *  for sponsoring the further development of this driver.
  11  *
  12  * **********************
  13  *
  14  * The original copyright was as follows:
  15  *
  16  * skeleton.c Written 1993 by Donald Becker.
  17  * Copyright 1993 United States Government as represented by the
  18  * Director, National Security Agency.  This software may only be used
  19  * and distributed according to the terms of the GNU General Public License as
  20  * modified by SRC, incorporated herein by reference.
  21  *
  22  * **********************
  23  *
  24  * The change log is now in a file called ChangeLog in this directory.
  25  *
  26  * Sources:
  27  *  - Crynwr arcnet.com/arcether.com packet drivers.
  28  *  - arcnet.c v0.00 dated 1/1/94 and apparently by
  29  *     Donald Becker - it didn't work :)
  30  *  - skeleton.c v0.05 dated 11/16/93 by Donald Becker
  31  *     (from Linux Kernel 1.1.45)
  32  *  - RFC's 1201 and 1051 - re: TCP/IP over ARCnet
  33  *  - The official ARCnet COM9026 data sheets (!) thanks to
  34  *     Ken Cornetet <kcornete@nyx10.cs.du.edu>
  35  *  - The official ARCnet COM20020 data sheets.
  36  *  - Information on some more obscure ARCnet controller chips, thanks
  37  *     to the nice people at SMSC.
  38  *  - net/inet/eth.c (from kernel 1.1.50) for header-building info.
  39  *  - Alternate Linux ARCnet source by V.Shergin <vsher@sao.stavropol.su>
  40  *  - Textual information and more alternate source from Joachim Koenig
  41  *     <jojo@repas.de>
  42  */
  43
  44 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  45
  46 #include <linux/module.h>
  47 #include <linux/types.h>
  48 #include <linux/delay.h>
  49 #include <linux/netdevice.h>
  50 #include <linux/if_arp.h>
  51 #include <net/arp.h>
  52 #include <linux/init.h>
  53 #include <linux/jiffies.h>
  54 #include <linux/errqueue.h>
  55
  56 #include <linux/leds.h>
  57
  58 #include "arcdevice.h"
  59 #include "com9026.h"
  60
  61 /* "do nothing" functions for protocol drivers */
  62 static void null_rx(struct net_device *dev, int bufnum,
  63                     struct archdr *pkthdr, int length);
  64 static int null_build_header(struct sk_buff *skb, struct net_device *dev,
  65                              unsigned short type, uint8_t daddr);
  66 static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
  67                            int length, int bufnum);
  68
  69 static void arcnet_rx(struct net_device *dev, int bufnum);
  70
  71 /* one ArcProto per possible proto ID.  None of the elements of
  72  * arc_proto_map are allowed to be NULL; they will get set to
  73  * arc_proto_default instead.  It also must not be NULL; if you would like
  74  * to set it to NULL, set it to &arc_proto_null instead.
  75  */
  76 struct ArcProto *arc_proto_map[256];
  77 EXPORT_SYMBOL(arc_proto_map);
  78
  79 struct ArcProto *arc_proto_default;
  80 EXPORT_SYMBOL(arc_proto_default);
  81
  82 struct ArcProto *arc_bcast_proto;
  83 EXPORT_SYMBOL(arc_bcast_proto);
  84
  85 struct ArcProto *arc_raw_proto;
  86 EXPORT_SYMBOL(arc_raw_proto);
  87
  88 static struct ArcProto arc_proto_null = {
  89         .suffix         = '?',
  90         .mtu            = XMTU,
  91         .is_ip          = 0,
  92         .rx             = null_rx,
  93         .build_header   = null_build_header,
  94         .prepare_tx     = null_prepare_tx,
  95         .continue_tx    = NULL,
  96         .ack_tx         = NULL
  97 };
  98
  99 /* Exported function prototypes */
 100 int arcnet_debug = ARCNET_DEBUG;
 101 EXPORT_SYMBOL(arcnet_debug);
 102
 103 /* Internal function prototypes */
 104 static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 105                          unsigned short type, const void *daddr,
 106                          const void *saddr, unsigned len);
 107 static int go_tx(struct net_device *dev);
 108
 109 static int debug = ARCNET_DEBUG;
 110 module_param(debug, int, 0);
 111 MODULE_LICENSE("GPL");
 112
 113 static int __init arcnet_init(void)
 114 {
 115         int count;
 116
 117         arcnet_debug = debug;
 118
 119         pr_info("arcnet loaded\n");
 120
 121         /* initialize the protocol map */
 122         arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
 123         for (count = 0; count < 256; count++)
 124                 arc_proto_map[count] = arc_proto_default;
 125
 126         if (BUGLVL(D_DURING))
 127                 pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
 128                         sizeof(struct arc_hardware),
 129                         sizeof(struct arc_rfc1201),
 130                         sizeof(struct arc_rfc1051),
 131                         sizeof(struct arc_eth_encap),
 132                         sizeof(struct archdr));
 133
 134         return 0;
 135 }
 136
 137 static void __exit arcnet_exit(void)
 138 {
 139 }
 140
 141 module_init(arcnet_init);
 142 module_exit(arcnet_exit);
 143
 144 /* Dump the contents of an sk_buff */
 145 #if ARCNET_DEBUG_MAX & D_SKB
 146 void arcnet_dump_skb(struct net_device *dev,
 147                      struct sk_buff *skb, char *desc)
 148 {
 149         char hdr[32];
 150
 151         /* dump the packet */
 152         snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
 153         print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 154                        16, 1, skb->data, skb->len, true);
 155 }
 156 EXPORT_SYMBOL(arcnet_dump_skb);
 157 #endif
 158
 159 /* Dump the contents of an ARCnet buffer */
 160 #if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 161 static void arcnet_dump_packet(struct net_device *dev, int bufnum,
 162                                char *desc, int take_arcnet_lock)
 163 {
 164         struct arcnet_local *lp = netdev_priv(dev);
 165         int i, length;
 166         unsigned long flags = 0;
 167         static uint8_t buf[512];
 168         char hdr[32];
 169
 170         /* hw.copy_from_card expects IRQ context so take the IRQ lock
 171          * to keep it single threaded
 172          */
 173         if (take_arcnet_lock)
 174                 spin_lock_irqsave(&lp->lock, flags);
 175
 176         lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
 177         if (take_arcnet_lock)
 178                 spin_unlock_irqrestore(&lp->lock, flags);
 179
 180         /* if the offset[0] byte is nonzero, this is a 256-byte packet */
 181         length = (buf[2] ? 256 : 512);
 182
 183         /* dump the packet */
 184         snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
 185         print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 186                        16, 1, buf, length, true);
 187 }
 188
 189 #else
 190
 191 #define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
 192
 193 #endif
 194
 195 /* Trigger a LED event in response to a ARCNET device event */
 196 void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
 197 {
 198         struct arcnet_local *lp = netdev_priv(dev);
 199         unsigned long led_delay = 350;
 200         unsigned long tx_delay = 50;
 201
 202         switch (event) {
 203         case ARCNET_LED_EVENT_RECON:
 204                 led_trigger_blink_oneshot(lp->recon_led_trig,
 205                                           &led_delay, &led_delay, 0);
 206                 break;
 207         case ARCNET_LED_EVENT_OPEN:
 208                 led_trigger_event(lp->tx_led_trig, LED_OFF);
 209                 led_trigger_event(lp->recon_led_trig, LED_OFF);
 210                 break;
 211         case ARCNET_LED_EVENT_STOP:
 212                 led_trigger_event(lp->tx_led_trig, LED_OFF);
 213                 led_trigger_event(lp->recon_led_trig, LED_OFF);
 214                 break;
 215         case ARCNET_LED_EVENT_TX:
 216                 led_trigger_blink_oneshot(lp->tx_led_trig,
 217                                           &tx_delay, &tx_delay, 0);
 218                 break;
 219         }
 220 }
 221 EXPORT_SYMBOL_GPL(arcnet_led_event);
 222
 223 static void arcnet_led_release(struct device *gendev, void *res)
 224 {
 225         struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
 226
 227         led_trigger_unregister_simple(lp->tx_led_trig);
 228         led_trigger_unregister_simple(lp->recon_led_trig);
 229 }
 230
 231 /* Register ARCNET LED triggers for a arcnet device
 232  *
 233  * This is normally called from a driver's probe function
 234  */
 235 void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
 236 {
 237         struct arcnet_local *lp = netdev_priv(netdev);
 238         void *res;
 239
 240         res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
 241         if (!res) {
 242                 netdev_err(netdev, "cannot register LED triggers\n");
 243                 return;
 244         }
 245
 246         snprintf(lp->tx_led_trig_name, sizeof(lp->tx_led_trig_name),
 247                  "arc%d-%d-tx", index, subid);
 248         snprintf(lp->recon_led_trig_name, sizeof(lp->recon_led_trig_name),
 249                  "arc%d-%d-recon", index, subid);
 250
 251         led_trigger_register_simple(lp->tx_led_trig_name,
 252                                     &lp->tx_led_trig);
 253         led_trigger_register_simple(lp->recon_led_trig_name,
 254                                     &lp->recon_led_trig);
 255
 256         devres_add(&netdev->dev, res);
 257 }
 258 EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
 259
 260 /* Unregister a protocol driver from the arc_proto_map.  Protocol drivers
 261  * are responsible for registering themselves, but the unregister routine
 262  * is pretty generic so we'll do it here.
 263  */
 264 void arcnet_unregister_proto(struct ArcProto *proto)
 265 {
 266         int count;
 267
 268         if (arc_proto_default == proto)
 269                 arc_proto_default = &arc_proto_null;
 270         if (arc_bcast_proto == proto)
 271                 arc_bcast_proto = arc_proto_default;
 272         if (arc_raw_proto == proto)
 273                 arc_raw_proto = arc_proto_default;
 274
 275         for (count = 0; count < 256; count++) {
 276                 if (arc_proto_map[count] == proto)
 277                         arc_proto_map[count] = arc_proto_default;
 278         }
 279 }
 280 EXPORT_SYMBOL(arcnet_unregister_proto);
 281
 282 /* Add a buffer to the queue.  Only the interrupt handler is allowed to do
 283  * this, unless interrupts are disabled.
 284  *
 285  * Note: we don't check for a full queue, since there aren't enough buffers
 286  * to more than fill it.
 287  */
 288 static void release_arcbuf(struct net_device *dev, int bufnum)
 289 {
 290         struct arcnet_local *lp = netdev_priv(dev);
 291         int i;
 292
 293         lp->buf_queue[lp->first_free_buf++] = bufnum;
 294         lp->first_free_buf %= 5;
 295
 296         if (BUGLVL(D_DURING)) {
 297                 arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
 298                            bufnum);
 299                 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 300                         arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 301                 arc_cont(D_DURING, "\n");
 302         }
 303 }
 304
 305 /* Get a buffer from the queue.
 306  * If this returns -1, there are no buffers available.
 307  */
 308 static int get_arcbuf(struct net_device *dev)
 309 {
 310         struct arcnet_local *lp = netdev_priv(dev);
 311         int buf = -1, i;
 312
 313         if (!atomic_dec_and_test(&lp->buf_lock)) {
 314                 /* already in this function */
 315                 arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
 316                            lp->buf_lock.counter);
 317         } else {                        /* we can continue */
 318                 if (lp->next_buf >= 5)
 319                         lp->next_buf -= 5;
 320
 321                 if (lp->next_buf == lp->first_free_buf) {
 322                         arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
 323                 } else {
 324                         buf = lp->buf_queue[lp->next_buf++];
 325                         lp->next_buf %= 5;
 326                 }
 327         }
 328
 329         if (BUGLVL(D_DURING)) {
 330                 arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
 331                            buf);
 332                 for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 333                         arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 334                 arc_cont(D_DURING, "\n");
 335         }
 336
 337         atomic_inc(&lp->buf_lock);
 338         return buf;
 339 }
 340
 341 static int choose_mtu(void)
 342 {
 343         int count, mtu = 65535;
 344
 345         /* choose the smallest MTU of all available encaps */
 346         for (count = 0; count < 256; count++) {
 347                 if (arc_proto_map[count] != &arc_proto_null &&
 348                     arc_proto_map[count]->mtu < mtu) {
 349                         mtu = arc_proto_map[count]->mtu;
 350                 }
 351         }
 352
 353         return mtu == 65535 ? XMTU : mtu;
 354 }
 355
 356 static const struct header_ops arcnet_header_ops = {
 357         .create = arcnet_header,
 358 };
 359
 360 static const struct net_device_ops arcnet_netdev_ops = {
 361         .ndo_open       = arcnet_open,
 362         .ndo_stop       = arcnet_close,
 363         .ndo_start_xmit = arcnet_send_packet,
 364         .ndo_tx_timeout = arcnet_timeout,
 365 };
 366
 367 /* Setup a struct device for ARCnet. */
 368 static void arcdev_setup(struct net_device *dev)
 369 {
 370         dev->type = ARPHRD_ARCNET;
 371         dev->netdev_ops = &arcnet_netdev_ops;
 372         dev->header_ops = &arcnet_header_ops;
 373         dev->hard_header_len = sizeof(struct arc_hardware);
 374         dev->mtu = choose_mtu();
 375
 376         dev->addr_len = ARCNET_ALEN;
 377         dev->tx_queue_len = 100;
 378         dev->broadcast[0] = 0x00;       /* for us, broadcasts are address 0 */
 379         dev->watchdog_timeo = TX_TIMEOUT;
 380
 381         /* New-style flags. */
 382         dev->flags = IFF_BROADCAST;
 383 }
 384
 385 static void arcnet_timer(unsigned long data)
 386 {
 387         struct net_device *dev = (struct net_device *)data;
 388
 389         if (!netif_carrier_ok(dev)) {
 390                 netif_carrier_on(dev);
 391                 netdev_info(dev, "link up\n");
 392         }
 393 }
 394
 395 static void arcnet_reply_tasklet(unsigned long data)
 396 {
 397         struct arcnet_local *lp = (struct arcnet_local *)data;
 398
 399         struct sk_buff *ackskb, *skb;
 400         struct sock_exterr_skb *serr;
 401         struct sock *sk;
 402         int ret;
 403
 404         local_irq_disable();
 405         skb = lp->outgoing.skb;
 406         if (!skb || !skb->sk) {
 407                 local_irq_enable();
 408                 return;
 409         }
 410
 411         sock_hold(skb->sk);
 412         sk = skb->sk;
 413         ackskb = skb_clone_sk(skb);
 414         sock_put(skb->sk);
 415
 416         if (!ackskb) {
 417                 local_irq_enable();
 418                 return;
 419         }
 420
 421         serr = SKB_EXT_ERR(ackskb);
 422         memset(serr, 0, sizeof(*serr));
 423         serr->ee.ee_errno = ENOMSG;
 424         serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
 425         serr->ee.ee_data = skb_shinfo(skb)->tskey;
 426         serr->ee.ee_info = lp->reply_status;
 427
 428         /* finally erasing outgoing skb */
 429         dev_kfree_skb(lp->outgoing.skb);
 430         lp->outgoing.skb = NULL;
 431
 432         ackskb->dev = lp->dev;
 433
 434         ret = sock_queue_err_skb(sk, ackskb);
 435         if (ret)
 436                 kfree_skb(ackskb);
 437
 438         local_irq_enable();
 439 };
 440
 441 struct net_device *alloc_arcdev(const char *name)
 442 {
 443         struct net_device *dev;
 444
 445         dev = alloc_netdev(sizeof(struct arcnet_local),
 446                            name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
 447                            arcdev_setup);
 448         if (dev) {
 449                 struct arcnet_local *lp = netdev_priv(dev);
 450
 451                 lp->dev = dev;
 452                 spin_lock_init(&lp->lock);
 453                 init_timer(&lp->timer);
 454                 lp->timer.data = (unsigned long) dev;
 455                 lp->timer.function = arcnet_timer;
 456         }
 457
 458         return dev;
 459 }
 460 EXPORT_SYMBOL(alloc_arcdev);
 461
 462 /* Open/initialize the board.  This is called sometime after booting when
 463  * the 'ifconfig' program is run.
 464  *
 465  * This routine should set everything up anew at each open, even registers
 466  * that "should" only need to be set once at boot, so that there is
 467  * non-reboot way to recover if something goes wrong.
 468  */
 469 int arcnet_open(struct net_device *dev)
 470 {
 471         struct arcnet_local *lp = netdev_priv(dev);
 472         int count, newmtu, error;
 473
 474         arc_printk(D_INIT, dev, "opened.");
 475
 476         if (!try_module_get(lp->hw.owner))
 477                 return -ENODEV;
 478
 479         if (BUGLVL(D_PROTO)) {
 480                 arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
 481                            arc_proto_default->suffix);
 482                 for (count = 0; count < 256; count++)
 483                         arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
 484                 arc_cont(D_PROTO, "\n");
 485         }
 486
 487         tasklet_init(&lp->reply_tasklet, arcnet_reply_tasklet,
 488                      (unsigned long)lp);
 489
 490         arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 491
 492         /* try to put the card in a defined state - if it fails the first
 493          * time, actually reset it.
 494          */
 495         error = -ENODEV;
 496         if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
 497                 goto out_module_put;
 498
 499         newmtu = choose_mtu();
 500         if (newmtu < dev->mtu)
 501                 dev->mtu = newmtu;
 502
 503         arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
 504
 505         /* autodetect the encapsulation for each host. */
 506         memset(lp->default_proto, 0, sizeof(lp->default_proto));
 507
 508         /* the broadcast address is special - use the 'bcast' protocol */
 509         for (count = 0; count < 256; count++) {
 510                 if (arc_proto_map[count] == arc_bcast_proto) {
 511                         lp->default_proto[0] = count;
 512                         break;
 513                 }
 514         }
 515
 516         /* initialize buffers */
 517         atomic_set(&lp->buf_lock, 1);
 518
 519         lp->next_buf = lp->first_free_buf = 0;
 520         release_arcbuf(dev, 0);
 521         release_arcbuf(dev, 1);
 522         release_arcbuf(dev, 2);
 523         release_arcbuf(dev, 3);
 524         lp->cur_tx = lp->next_tx = -1;
 525         lp->cur_rx = -1;
 526
 527         lp->rfc1201.sequence = 1;
 528
 529         /* bring up the hardware driver */
 530         if (lp->hw.open)
 531                 lp->hw.open(dev);
 532
 533         if (dev->dev_addr[0] == 0)
 534                 arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
 535         else if (dev->dev_addr[0] == 255)
 536                 arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
 537
 538         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 539         if (lp->hw.status(dev) & RESETflag) {
 540                 arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
 541                            __FILE__, __LINE__, __func__);
 542                 lp->hw.command(dev, CFLAGScmd | RESETclear);
 543         }
 544
 545         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 546         /* make sure we're ready to receive IRQ's. */
 547         lp->hw.intmask(dev, 0);
 548         udelay(1);              /* give it time to set the mask before
 549                                  * we reset it again. (may not even be
 550                                  * necessary)
 551                                  */
 552         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 553         lp->intmask = NORXflag | RECONflag;
 554         lp->hw.intmask(dev, lp->intmask);
 555         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 556
 557         netif_carrier_off(dev);
 558         netif_start_queue(dev);
 559         mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 560
 561         arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
 562         return 0;
 563
 564  out_module_put:
 565         module_put(lp->hw.owner);
 566         return error;
 567 }
 568 EXPORT_SYMBOL(arcnet_open);
 569
 570 /* The inverse routine to arcnet_open - shuts down the card. */
 571 int arcnet_close(struct net_device *dev)
 572 {
 573         struct arcnet_local *lp = netdev_priv(dev);
 574
 575         arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
 576         del_timer_sync(&lp->timer);
 577
 578         netif_stop_queue(dev);
 579         netif_carrier_off(dev);
 580
 581         tasklet_kill(&lp->reply_tasklet);
 582
 583         /* flush TX and disable RX */
 584         lp->hw.intmask(dev, 0);
 585         lp->hw.command(dev, NOTXcmd);   /* stop transmit */
 586         lp->hw.command(dev, NORXcmd);   /* disable receive */
 587         mdelay(1);
 588
 589         /* shut down the card */
 590         lp->hw.close(dev);
 591         module_put(lp->hw.owner);
 592         return 0;
 593 }
 594 EXPORT_SYMBOL(arcnet_close);
 595
 596 static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 597                          unsigned short type, const void *daddr,
 598                          const void *saddr, unsigned len)
 599 {
 600         const struct arcnet_local *lp = netdev_priv(dev);
 601         uint8_t _daddr, proto_num;
 602         struct ArcProto *proto;
 603
 604         arc_printk(D_DURING, dev,
 605                    "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 606                    saddr ? *(uint8_t *)saddr : -1,
 607                    daddr ? *(uint8_t *)daddr : -1,
 608                    type, type, len);
 609
 610         if (skb->len != 0 && len != skb->len)
 611                 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 612                            skb->len, len);
 613
 614         /* Type is host order - ? */
 615         if (type == ETH_P_ARCNET) {
 616                 proto = arc_raw_proto;
 617                 arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
 618                            proto->suffix);
 619                 _daddr = daddr ? *(uint8_t *)daddr : 0;
 620         } else if (!daddr) {
 621                 /* if the dest addr isn't provided, we can't choose an
 622                  * encapsulation!  Store the packet type (eg. ETH_P_IP)
 623                  * for now, and we'll push on a real header when we do
 624                  * rebuild_header.
 625                  */
 626                 *(uint16_t *)skb_push(skb, 2) = type;
 627                 /* XXX: Why not use skb->mac_len? */
 628                 if (skb->network_header - skb->mac_header != 2)
 629                         arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
 630                                    skb->network_header - skb->mac_header);
 631                 return -2;      /* return error -- can't transmit yet! */
 632         } else {
 633                 /* otherwise, we can just add the header as usual. */
 634                 _daddr = *(uint8_t *)daddr;
 635                 proto_num = lp->default_proto[_daddr];
 636                 proto = arc_proto_map[proto_num];
 637                 arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
 638                            proto_num, proto->suffix);
 639                 if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 640                         arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
 641                                    arc_bcast_proto->suffix);
 642                         proto = arc_bcast_proto;
 643                 }
 644         }
 645         return proto->build_header(skb, dev, type, _daddr);
 646 }
 647
 648 /* Called by the kernel in order to transmit a packet. */
 649 netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 650                                struct net_device *dev)
 651 {
 652         struct arcnet_local *lp = netdev_priv(dev);
 653         struct archdr *pkt;
 654         struct arc_rfc1201 *soft;
 655         struct ArcProto *proto;
 656         int txbuf;
 657         unsigned long flags;
 658         int retval;
 659
 660         arc_printk(D_DURING, dev,
 661                    "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 662                    lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
 663
 664         pkt = (struct archdr *)skb->data;
 665         soft = &pkt->soft.rfc1201;
 666         proto = arc_proto_map[soft->proto];
 667
 668         arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
 669                    skb->len, pkt->hard.dest);
 670         if (BUGLVL(D_SKB))
 671                 arcnet_dump_skb(dev, skb, "tx");
 672
 673         /* fits in one packet? */
 674         if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 675                 arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
 676                 dev_kfree_skb(skb);
 677                 return NETDEV_TX_OK;    /* don't try again */
 678         }
 679
 680         /* We're busy transmitting a packet... */
 681         netif_stop_queue(dev);
 682
 683         spin_lock_irqsave(&lp->lock, flags);
 684         lp->hw.intmask(dev, 0);
 685         if (lp->next_tx == -1)
 686                 txbuf = get_arcbuf(dev);
 687         else
 688                 txbuf = -1;
 689
 690         if (txbuf != -1) {
 691                 lp->outgoing.skb = skb;
 692                 if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 693                     !proto->ack_tx) {
 694                         /* done right away and we don't want to acknowledge
 695                          *  the package later - forget about it now
 696                          */
 697                         dev->stats.tx_bytes += skb->len;
 698                 } else {
 699                         /* do it the 'split' way */
 700                         lp->outgoing.proto = proto;
 701                         lp->outgoing.skb = skb;
 702                         lp->outgoing.pkt = pkt;
 703
 704                         if (proto->continue_tx &&
 705                             proto->continue_tx(dev, txbuf)) {
 706                                 arc_printk(D_NORMAL, dev,
 707                                            "bug! continue_tx finished the first time! (proto='%c')\n",
 708                                            proto->suffix);
 709                         }
 710                 }
 711                 retval = NETDEV_TX_OK;
 712                 lp->next_tx = txbuf;
 713         } else {
 714                 retval = NETDEV_TX_BUSY;
 715         }
 716
 717         arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 718                    __FILE__, __LINE__, __func__, lp->hw.status(dev));
 719         /* make sure we didn't ignore a TX IRQ while we were in here */
 720         lp->hw.intmask(dev, 0);
 721
 722         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 723         lp->intmask |= TXFREEflag | EXCNAKflag;
 724         lp->hw.intmask(dev, lp->intmask);
 725         arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 726                    __FILE__, __LINE__, __func__, lp->hw.status(dev));
 727
 728         arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
 729
 730         spin_unlock_irqrestore(&lp->lock, flags);
 731         return retval;          /* no need to try again */
 732 }
 733 EXPORT_SYMBOL(arcnet_send_packet);
 734
 735 /* Actually start transmitting a packet that was loaded into a buffer
 736  * by prepare_tx.  This should _only_ be called by the interrupt handler.
 737  */
 738 static int go_tx(struct net_device *dev)
 739 {
 740         struct arcnet_local *lp = netdev_priv(dev);
 741
 742         arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 743                    lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
 744
 745         if (lp->cur_tx != -1 || lp->next_tx == -1)
 746                 return 0;
 747
 748         if (BUGLVL(D_TX))
 749                 arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 750
 751         lp->cur_tx = lp->next_tx;
 752         lp->next_tx = -1;
 753
 754         /* start sending */
 755         lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
 756
 757         dev->stats.tx_packets++;
 758         lp->lasttrans_dest = lp->lastload_dest;
 759         lp->lastload_dest = 0;
 760         lp->excnak_pending = 0;
 761         lp->intmask |= TXFREEflag | EXCNAKflag;
 762
 763         return 1;
 764 }
 765
 766 /* Called by the kernel when transmit times out */
 767 void arcnet_timeout(struct net_device *dev)
 768 {
 769         unsigned long flags;
 770         struct arcnet_local *lp = netdev_priv(dev);
 771         int status = lp->hw.status(dev);
 772         char *msg;
 773
 774         spin_lock_irqsave(&lp->lock, flags);
 775         if (status & TXFREEflag) {      /* transmit _DID_ finish */
 776                 msg = " - missed IRQ?";
 777         } else {
 778                 msg = "";
 779                 dev->stats.tx_aborted_errors++;
 780                 lp->timed_out = 1;
 781                 lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
 782         }
 783         dev->stats.tx_errors++;
 784
 785         /* make sure we didn't miss a TX or a EXC NAK IRQ */
 786         lp->hw.intmask(dev, 0);
 787         lp->intmask |= TXFREEflag | EXCNAKflag;
 788         lp->hw.intmask(dev, lp->intmask);
 789
 790         spin_unlock_irqrestore(&lp->lock, flags);
 791
 792         if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
 793                 arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 794                            msg, status, lp->intmask, lp->lasttrans_dest);
 795                 lp->last_timeout = jiffies;
 796         }
 797
 798         if (lp->cur_tx == -1)
 799                 netif_wake_queue(dev);
 800 }
 801 EXPORT_SYMBOL(arcnet_timeout);
 802
 803 /* The typical workload of the driver: Handle the network interface
 804  * interrupts. Establish which device needs attention, and call the correct
 805  * chipset interrupt handler.
 806  */
 807 irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 808 {
 809         struct net_device *dev = dev_id;
 810         struct arcnet_local *lp;
 811         int recbuf, status, diagstatus, didsomething, boguscount;
 812         unsigned long flags;
 813         int retval = IRQ_NONE;
 814
 815         arc_printk(D_DURING, dev, "\n");
 816
 817         arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
 818
 819         lp = netdev_priv(dev);
 820         BUG_ON(!lp);
 821
 822         spin_lock_irqsave(&lp->lock, flags);
 823
 824         /* RESET flag was enabled - if device is not running, we must
 825          * clear it right away (but nothing else).
 826          */
 827         if (!netif_running(dev)) {
 828                 if (lp->hw.status(dev) & RESETflag)
 829                         lp->hw.command(dev, CFLAGScmd | RESETclear);
 830                 lp->hw.intmask(dev, 0);
 831                 spin_unlock_irqrestore(&lp->lock, flags);
 832                 return retval;
 833         }
 834
 835         arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 836                    lp->hw.status(dev), lp->intmask);
 837
 838         boguscount = 5;
 839         do {
 840                 status = lp->hw.status(dev);
 841                 diagstatus = (status >> 8) & 0xFF;
 842
 843                 arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
 844                            __FILE__, __LINE__, __func__, status);
 845                 didsomething = 0;
 846
 847                 /* RESET flag was enabled - card is resetting and if RX is
 848                  * disabled, it's NOT because we just got a packet.
 849                  *
 850                  * The card is in an undefined state.
 851                  * Clear it out and start over.
 852                  */
 853                 if (status & RESETflag) {
 854                         arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 855                                    status);
 856                         arcnet_close(dev);
 857                         arcnet_open(dev);
 858
 859                         /* get out of the interrupt handler! */
 860                         break;
 861                 }
 862                 /* RX is inhibited - we must have received something.
 863                  * Prepare to receive into the next buffer.
 864                  *
 865                  * We don't actually copy the received packet from the card
 866                  * until after the transmit handler runs (and possibly
 867                  * launches the next tx); this should improve latency slightly
 868                  * if we get both types of interrupts at once.
 869                  */
 870                 recbuf = -1;
 871                 if (status & lp->intmask & NORXflag) {
 872                         recbuf = lp->cur_rx;
 873                         arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
 874                                    recbuf, status);
 875
 876                         lp->cur_rx = get_arcbuf(dev);
 877                         if (lp->cur_rx != -1) {
 878                                 arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
 879                                            lp->cur_rx);
 880                                 lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
 881                         }
 882                         didsomething++;
 883                 }
 884
 885                 if ((diagstatus & EXCNAKflag)) {
 886                         arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
 887                                    diagstatus);
 888
 889                         lp->hw.command(dev, NOTXcmd);      /* disable transmit */
 890                         lp->excnak_pending = 1;
 891
 892                         lp->hw.command(dev, EXCNAKclear);
 893                         lp->intmask &= ~(EXCNAKflag);
 894                         didsomething++;
 895                 }
 896
 897                 /* a transmit finished, and we're interested in it. */
 898                 if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 899                         int ackstatus;
 900                         lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 901
 902                         if (status & TXACKflag)
 903                                 ackstatus = 2;
 904                         else if (lp->excnak_pending)
 905                                 ackstatus = 1;
 906                         else
 907                                 ackstatus = 0;
 908
 909                         arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
 910                                    status);
 911
 912                         if (lp->cur_tx != -1 && !lp->timed_out) {
 913                                 if (!(status & TXACKflag)) {
 914                                         if (lp->lasttrans_dest != 0) {
 915                                                 arc_printk(D_EXTRA, dev,
 916                                                            "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
 917                                                            status,
 918                                                            lp->lasttrans_dest);
 919                                                 dev->stats.tx_errors++;
 920                                                 dev->stats.tx_carrier_errors++;
 921                                         } else {
 922                                                 arc_printk(D_DURING, dev,
 923                                                            "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
 924                                                            status,
 925                                                            lp->lasttrans_dest);
 926                                         }
 927                                 }
 928
 929                                 if (lp->outgoing.proto &&
 930                                     lp->outgoing.proto->ack_tx) {
 931                                         lp->outgoing.proto
 932                                                 ->ack_tx(dev, ackstatus);
 933                                 }
 934                                 lp->reply_status = ackstatus;
 935                                 tasklet_hi_schedule(&lp->reply_tasklet);
 936                         }
 937                         if (lp->cur_tx != -1)
 938                                 release_arcbuf(dev, lp->cur_tx);
 939
 940                         lp->cur_tx = -1;
 941                         lp->timed_out = 0;
 942                         didsomething++;
 943
 944                         /* send another packet if there is one */
 945                         go_tx(dev);
 946
 947                         /* continue a split packet, if any */
 948                         if (lp->outgoing.proto &&
 949                             lp->outgoing.proto->continue_tx) {
 950                                 int txbuf = get_arcbuf(dev);
 951
 952                                 if (txbuf != -1) {
 953                                         if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
 954                                                 /* that was the last segment */
 955                                                 dev->stats.tx_bytes += lp->outgoing.skb->len;
 956                                                 if (!lp->outgoing.proto->ack_tx) {
 957                                                         dev_kfree_skb_irq(lp->outgoing.skb);
 958                                                         lp->outgoing.proto = NULL;
 959                                                 }
 960                                         }
 961                                         lp->next_tx = txbuf;
 962                                 }
 963                         }
 964                         /* inform upper layers of idleness, if necessary */
 965                         if (lp->cur_tx == -1)
 966                                 netif_wake_queue(dev);
 967                 }
 968                 /* now process the received packet, if any */
 969                 if (recbuf != -1) {
 970                         if (BUGLVL(D_RX))
 971                                 arcnet_dump_packet(dev, recbuf, "rx irq", 0);
 972
 973                         arcnet_rx(dev, recbuf);
 974                         release_arcbuf(dev, recbuf);
 975
 976                         didsomething++;
 977                 }
 978                 if (status & lp->intmask & RECONflag) {
 979                         lp->hw.command(dev, CFLAGScmd | CONFIGclear);
 980                         dev->stats.tx_carrier_errors++;
 981
 982                         arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
 983                                    status);
 984                         if (netif_carrier_ok(dev)) {
 985                                 netif_carrier_off(dev);
 986                                 netdev_info(dev, "link down\n");
 987                         }
 988                         mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 989
 990                         arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
 991                         /* MYRECON bit is at bit 7 of diagstatus */
 992                         if (diagstatus & 0x80)
 993                                 arc_printk(D_RECON, dev, "Put out that recon myself\n");
 994
 995                         /* is the RECON info empty or old? */
 996                         if (!lp->first_recon || !lp->last_recon ||
 997                             time_after(jiffies, lp->last_recon + HZ * 10)) {
 998                                 if (lp->network_down)
 999                                         arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1000                                 lp->first_recon = lp->last_recon = jiffies;
1001                                 lp->num_recons = lp->network_down = 0;
1002
1003                                 arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1004                         } else {        /* add to current RECON counter */
1005                                 lp->last_recon = jiffies;
1006                                 lp->num_recons++;
1007
1008                                 arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1009                                            lp->num_recons,
1010                                            (lp->last_recon - lp->first_recon) / HZ,
1011                                            lp->network_down);
1012
1013                                 /* if network is marked up;
1014                                  * and first_recon and last_recon are 60+ apart;
1015                                  * and the average no. of recons counted is
1016                                  *    > RECON_THRESHOLD/min;
1017                                  * then print a warning message.
1018                                  */
1019                                 if (!lp->network_down &&
1020                                     (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1021                                     lp->num_recons >= RECON_THRESHOLD) {
1022                                         lp->network_down = 1;
1023                                         arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1024                                 } else if (!lp->network_down &&
1025                                            lp->last_recon - lp->first_recon > HZ * 60) {
1026                                         /* reset counters if we've gone for
1027                                          *  over a minute.
1028                                          */
1029                                         lp->first_recon = lp->last_recon;
1030                                         lp->num_recons = 1;
1031                                 }
1032                         }
1033                 } else if (lp->network_down &&
1034                            time_after(jiffies, lp->last_recon + HZ * 10)) {
1035                         if (lp->network_down)
1036                                 arc_printk(D_NORMAL, dev, "cabling restored?\n");
1037                         lp->first_recon = lp->last_recon = 0;
1038                         lp->num_recons = lp->network_down = 0;
1039
1040                         arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1041                         netif_carrier_on(dev);
1042                 }
1043
1044                 if (didsomething)
1045                         retval |= IRQ_HANDLED;
1046         } while (--boguscount && didsomething);
1047
1048         arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1049                    lp->hw.status(dev), boguscount);
1050         arc_printk(D_DURING, dev, "\n");
1051
1052         lp->hw.intmask(dev, 0);
1053         udelay(1);
1054         lp->hw.intmask(dev, lp->intmask);
1055
1056         spin_unlock_irqrestore(&lp->lock, flags);
1057         return retval;
1058 }
1059 EXPORT_SYMBOL(arcnet_interrupt);
1060
1061 /* This is a generic packet receiver that calls arcnet??_rx depending on the
1062  * protocol ID found.
1063  */
1064 static void arcnet_rx(struct net_device *dev, int bufnum)
1065 {
1066         struct arcnet_local *lp = netdev_priv(dev);
1067         union {
1068                 struct archdr pkt;
1069                 char buf[512];
1070         } rxdata;
1071         struct arc_rfc1201 *soft;
1072         int length, ofs;
1073
1074         soft = &rxdata.pkt.soft.rfc1201;
1075
1076         lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1077         if (rxdata.pkt.hard.offset[0]) {
1078                 ofs = rxdata.pkt.hard.offset[0];
1079                 length = 256 - ofs;
1080         } else {
1081                 ofs = rxdata.pkt.hard.offset[1];
1082                 length = 512 - ofs;
1083         }
1084
1085         /* get the full header, if possible */
1086         if (sizeof(rxdata.pkt.soft) <= length) {
1087                 lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1088         } else {
1089                 memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1090                 lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1091         }
1092
1093         arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1094                    bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1095
1096         dev->stats.rx_packets++;
1097         dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1098
1099         /* call the right receiver for the protocol */
1100         if (arc_proto_map[soft->proto]->is_ip) {
1101                 if (BUGLVL(D_PROTO)) {
1102                         struct ArcProto
1103                         *oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1104                         *newp = arc_proto_map[soft->proto];
1105
1106                         if (oldp != newp) {
1107                                 arc_printk(D_PROTO, dev,
1108                                            "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1109                                            soft->proto, rxdata.pkt.hard.source,
1110                                            newp->suffix, oldp->suffix);
1111                         }
1112                 }
1113
1114                 /* broadcasts will always be done with the last-used encap. */
1115                 lp->default_proto[0] = soft->proto;
1116
1117                 /* in striking contrast, the following isn't a hack. */
1118                 lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1119         }
1120         /* call the protocol-specific receiver. */
1121         arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1122 }
1123
1124 static void null_rx(struct net_device *dev, int bufnum,
1125                     struct archdr *pkthdr, int length)
1126 {
1127         arc_printk(D_PROTO, dev,
1128                    "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1129                    pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1130 }
1131
1132 static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1133                              unsigned short type, uint8_t daddr)
1134 {
1135         struct arcnet_local *lp = netdev_priv(dev);
1136
1137         arc_printk(D_PROTO, dev,
1138                    "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1139                    lp->default_proto[daddr]);
1140
1141         /* always fails */
1142         return 0;
1143 }
1144
1145 /* the "do nothing" prepare_tx function warns that there's nothing to do. */
1146 static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1147                            int length, int bufnum)
1148 {
1149         struct arcnet_local *lp = netdev_priv(dev);
1150         struct arc_hardware newpkt;
1151
1152         arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1153
1154         /* send a packet to myself -- will never get received, of course */
1155         newpkt.source = newpkt.dest = dev->dev_addr[0];
1156
1157         /* only one byte of actual data (and it's random) */
1158         newpkt.offset[0] = 0xFF;
1159
1160         lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1161
1162         return 1;               /* done */
1163 }