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(struct timer_list *t)
 386 {
 387         struct arcnet_local *lp = from_timer(lp, t, timer);
 388         struct net_device *dev = lp->dev;
 389
 390         if (!netif_carrier_ok(dev)) {
 391                 netif_carrier_on(dev);
 392                 netdev_info(dev, "link up\n");
 393         }
 394 }
 395
 396 static void arcnet_reply_tasklet(unsigned long data)
 397 {
 398         struct arcnet_local *lp = (struct arcnet_local *)data;
 399
 400         struct sk_buff *ackskb, *skb;
 401         struct sock_exterr_skb *serr;
 402         struct sock *sk;
 403         int ret;
 404
 405         local_irq_disable();
 406         skb = lp->outgoing.skb;
 407         if (!skb || !skb->sk) {
 408                 local_irq_enable();
 409                 return;
 410         }
 411
 412         sock_hold(skb->sk);
 413         sk = skb->sk;
 414         ackskb = skb_clone_sk(skb);
 415         sock_put(skb->sk);
 416
 417         if (!ackskb) {
 418                 local_irq_enable();
 419                 return;
 420         }
 421
 422         serr = SKB_EXT_ERR(ackskb);
 423         memset(serr, 0, sizeof(*serr));
 424         serr->ee.ee_errno = ENOMSG;
 425         serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
 426         serr->ee.ee_data = skb_shinfo(skb)->tskey;
 427         serr->ee.ee_info = lp->reply_status;
 428
 429         /* finally erasing outgoing skb */
 430         dev_kfree_skb(lp->outgoing.skb);
 431         lp->outgoing.skb = NULL;
 432
 433         ackskb->dev = lp->dev;
 434
 435         ret = sock_queue_err_skb(sk, ackskb);
 436         if (ret)
 437                 dev_kfree_skb_irq(ackskb);
 438
 439         local_irq_enable();
 440 };
 441
 442 struct net_device *alloc_arcdev(const char *name)
 443 {
 444         struct net_device *dev;
 445
 446         dev = alloc_netdev(sizeof(struct arcnet_local),
 447                            name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
 448                            arcdev_setup);
 449         if (dev) {
 450                 struct arcnet_local *lp = netdev_priv(dev);
 451
 452                 lp->dev = dev;
 453                 spin_lock_init(&lp->lock);
 454                 timer_setup(&lp->timer, arcnet_timer, 0);
 455         }
 456
 457         return dev;
 458 }
 459 EXPORT_SYMBOL(alloc_arcdev);
 460
 461 /* Open/initialize the board.  This is called sometime after booting when
 462  * the 'ifconfig' program is run.
 463  *
 464  * This routine should set everything up anew at each open, even registers
 465  * that "should" only need to be set once at boot, so that there is
 466  * non-reboot way to recover if something goes wrong.
 467  */
 468 int arcnet_open(struct net_device *dev)
 469 {
 470         struct arcnet_local *lp = netdev_priv(dev);
 471         int count, newmtu, error;
 472
 473         arc_printk(D_INIT, dev, "opened.");
 474
 475         if (!try_module_get(lp->hw.owner))
 476                 return -ENODEV;
 477
 478         if (BUGLVL(D_PROTO)) {
 479                 arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
 480                            arc_proto_default->suffix);
 481                 for (count = 0; count < 256; count++)
 482                         arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
 483                 arc_cont(D_PROTO, "\n");
 484         }
 485
 486         tasklet_init(&lp->reply_tasklet, arcnet_reply_tasklet,
 487                      (unsigned long)lp);
 488
 489         arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 490
 491         /* try to put the card in a defined state - if it fails the first
 492          * time, actually reset it.
 493          */
 494         error = -ENODEV;
 495         if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
 496                 goto out_module_put;
 497
 498         newmtu = choose_mtu();
 499         if (newmtu < dev->mtu)
 500                 dev->mtu = newmtu;
 501
 502         arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
 503
 504         /* autodetect the encapsulation for each host. */
 505         memset(lp->default_proto, 0, sizeof(lp->default_proto));
 506
 507         /* the broadcast address is special - use the 'bcast' protocol */
 508         for (count = 0; count < 256; count++) {
 509                 if (arc_proto_map[count] == arc_bcast_proto) {
 510                         lp->default_proto[0] = count;
 511                         break;
 512                 }
 513         }
 514
 515         /* initialize buffers */
 516         atomic_set(&lp->buf_lock, 1);
 517
 518         lp->next_buf = lp->first_free_buf = 0;
 519         release_arcbuf(dev, 0);
 520         release_arcbuf(dev, 1);
 521         release_arcbuf(dev, 2);
 522         release_arcbuf(dev, 3);
 523         lp->cur_tx = lp->next_tx = -1;
 524         lp->cur_rx = -1;
 525
 526         lp->rfc1201.sequence = 1;
 527
 528         /* bring up the hardware driver */
 529         if (lp->hw.open)
 530                 lp->hw.open(dev);
 531
 532         if (dev->dev_addr[0] == 0)
 533                 arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
 534         else if (dev->dev_addr[0] == 255)
 535                 arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
 536
 537         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 538         if (lp->hw.status(dev) & RESETflag) {
 539                 arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
 540                            __FILE__, __LINE__, __func__);
 541                 lp->hw.command(dev, CFLAGScmd | RESETclear);
 542         }
 543
 544         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 545         /* make sure we're ready to receive IRQ's. */
 546         lp->hw.intmask(dev, 0);
 547         udelay(1);              /* give it time to set the mask before
 548                                  * we reset it again. (may not even be
 549                                  * necessary)
 550                                  */
 551         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 552         lp->intmask = NORXflag | RECONflag;
 553         lp->hw.intmask(dev, lp->intmask);
 554         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 555
 556         netif_carrier_off(dev);
 557         netif_start_queue(dev);
 558         mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 559
 560         arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
 561         return 0;
 562
 563  out_module_put:
 564         module_put(lp->hw.owner);
 565         return error;
 566 }
 567 EXPORT_SYMBOL(arcnet_open);
 568
 569 /* The inverse routine to arcnet_open - shuts down the card. */
 570 int arcnet_close(struct net_device *dev)
 571 {
 572         struct arcnet_local *lp = netdev_priv(dev);
 573
 574         arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
 575         del_timer_sync(&lp->timer);
 576
 577         netif_stop_queue(dev);
 578         netif_carrier_off(dev);
 579
 580         tasklet_kill(&lp->reply_tasklet);
 581
 582         /* flush TX and disable RX */
 583         lp->hw.intmask(dev, 0);
 584         lp->hw.command(dev, NOTXcmd);   /* stop transmit */
 585         lp->hw.command(dev, NORXcmd);   /* disable receive */
 586         mdelay(1);
 587
 588         /* shut down the card */
 589         lp->hw.close(dev);
 590         module_put(lp->hw.owner);
 591         return 0;
 592 }
 593 EXPORT_SYMBOL(arcnet_close);
 594
 595 static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 596                          unsigned short type, const void *daddr,
 597                          const void *saddr, unsigned len)
 598 {
 599         const struct arcnet_local *lp = netdev_priv(dev);
 600         uint8_t _daddr, proto_num;
 601         struct ArcProto *proto;
 602
 603         arc_printk(D_DURING, dev,
 604                    "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 605                    saddr ? *(uint8_t *)saddr : -1,
 606                    daddr ? *(uint8_t *)daddr : -1,
 607                    type, type, len);
 608
 609         if (skb->len != 0 && len != skb->len)
 610                 arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 611                            skb->len, len);
 612
 613         /* Type is host order - ? */
 614         if (type == ETH_P_ARCNET) {
 615                 proto = arc_raw_proto;
 616                 arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
 617                            proto->suffix);
 618                 _daddr = daddr ? *(uint8_t *)daddr : 0;
 619         } else if (!daddr) {
 620                 /* if the dest addr isn't provided, we can't choose an
 621                  * encapsulation!  Store the packet type (eg. ETH_P_IP)
 622                  * for now, and we'll push on a real header when we do
 623                  * rebuild_header.
 624                  */
 625                 *(uint16_t *)skb_push(skb, 2) = type;
 626                 /* XXX: Why not use skb->mac_len? */
 627                 if (skb->network_header - skb->mac_header != 2)
 628                         arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
 629                                    skb->network_header - skb->mac_header);
 630                 return -2;      /* return error -- can't transmit yet! */
 631         } else {
 632                 /* otherwise, we can just add the header as usual. */
 633                 _daddr = *(uint8_t *)daddr;
 634                 proto_num = lp->default_proto[_daddr];
 635                 proto = arc_proto_map[proto_num];
 636                 arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
 637                            proto_num, proto->suffix);
 638                 if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 639                         arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
 640                                    arc_bcast_proto->suffix);
 641                         proto = arc_bcast_proto;
 642                 }
 643         }
 644         return proto->build_header(skb, dev, type, _daddr);
 645 }
 646
 647 /* Called by the kernel in order to transmit a packet. */
 648 netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 649                                struct net_device *dev)
 650 {
 651         struct arcnet_local *lp = netdev_priv(dev);
 652         struct archdr *pkt;
 653         struct arc_rfc1201 *soft;
 654         struct ArcProto *proto;
 655         int txbuf;
 656         unsigned long flags;
 657         int retval;
 658
 659         arc_printk(D_DURING, dev,
 660                    "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 661                    lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
 662
 663         pkt = (struct archdr *)skb->data;
 664         soft = &pkt->soft.rfc1201;
 665         proto = arc_proto_map[soft->proto];
 666
 667         arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
 668                    skb->len, pkt->hard.dest);
 669         if (BUGLVL(D_SKB))
 670                 arcnet_dump_skb(dev, skb, "tx");
 671
 672         /* fits in one packet? */
 673         if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 674                 arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
 675                 dev_kfree_skb(skb);
 676                 return NETDEV_TX_OK;    /* don't try again */
 677         }
 678
 679         /* We're busy transmitting a packet... */
 680         netif_stop_queue(dev);
 681
 682         spin_lock_irqsave(&lp->lock, flags);
 683         lp->hw.intmask(dev, 0);
 684         if (lp->next_tx == -1)
 685                 txbuf = get_arcbuf(dev);
 686         else
 687                 txbuf = -1;
 688
 689         if (txbuf != -1) {
 690                 lp->outgoing.skb = skb;
 691                 if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 692                     !proto->ack_tx) {
 693                         /* done right away and we don't want to acknowledge
 694                          *  the package later - forget about it now
 695                          */
 696                         dev->stats.tx_bytes += skb->len;
 697                 } else {
 698                         /* do it the 'split' way */
 699                         lp->outgoing.proto = proto;
 700                         lp->outgoing.skb = skb;
 701                         lp->outgoing.pkt = pkt;
 702
 703                         if (proto->continue_tx &&
 704                             proto->continue_tx(dev, txbuf)) {
 705                                 arc_printk(D_NORMAL, dev,
 706                                            "bug! continue_tx finished the first time! (proto='%c')\n",
 707                                            proto->suffix);
 708                         }
 709                 }
 710                 retval = NETDEV_TX_OK;
 711                 lp->next_tx = txbuf;
 712         } else {
 713                 retval = NETDEV_TX_BUSY;
 714         }
 715
 716         arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 717                    __FILE__, __LINE__, __func__, lp->hw.status(dev));
 718         /* make sure we didn't ignore a TX IRQ while we were in here */
 719         lp->hw.intmask(dev, 0);
 720
 721         arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 722         lp->intmask |= TXFREEflag | EXCNAKflag;
 723         lp->hw.intmask(dev, lp->intmask);
 724         arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 725                    __FILE__, __LINE__, __func__, lp->hw.status(dev));
 726
 727         arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
 728
 729         spin_unlock_irqrestore(&lp->lock, flags);
 730         return retval;          /* no need to try again */
 731 }
 732 EXPORT_SYMBOL(arcnet_send_packet);
 733
 734 /* Actually start transmitting a packet that was loaded into a buffer
 735  * by prepare_tx.  This should _only_ be called by the interrupt handler.
 736  */
 737 static int go_tx(struct net_device *dev)
 738 {
 739         struct arcnet_local *lp = netdev_priv(dev);
 740
 741         arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 742                    lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
 743
 744         if (lp->cur_tx != -1 || lp->next_tx == -1)
 745                 return 0;
 746
 747         if (BUGLVL(D_TX))
 748                 arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 749
 750         lp->cur_tx = lp->next_tx;
 751         lp->next_tx = -1;
 752
 753         /* start sending */
 754         lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
 755
 756         dev->stats.tx_packets++;
 757         lp->lasttrans_dest = lp->lastload_dest;
 758         lp->lastload_dest = 0;
 759         lp->excnak_pending = 0;
 760         lp->intmask |= TXFREEflag | EXCNAKflag;
 761
 762         return 1;
 763 }
 764
 765 /* Called by the kernel when transmit times out */
 766 void arcnet_timeout(struct net_device *dev)
 767 {
 768         unsigned long flags;
 769         struct arcnet_local *lp = netdev_priv(dev);
 770         int status = lp->hw.status(dev);
 771         char *msg;
 772
 773         spin_lock_irqsave(&lp->lock, flags);
 774         if (status & TXFREEflag) {      /* transmit _DID_ finish */
 775                 msg = " - missed IRQ?";
 776         } else {
 777                 msg = "";
 778                 dev->stats.tx_aborted_errors++;
 779                 lp->timed_out = 1;
 780                 lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
 781         }
 782         dev->stats.tx_errors++;
 783
 784         /* make sure we didn't miss a TX or a EXC NAK IRQ */
 785         lp->hw.intmask(dev, 0);
 786         lp->intmask |= TXFREEflag | EXCNAKflag;
 787         lp->hw.intmask(dev, lp->intmask);
 788
 789         spin_unlock_irqrestore(&lp->lock, flags);
 790
 791         if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
 792                 arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 793                            msg, status, lp->intmask, lp->lasttrans_dest);
 794                 lp->last_timeout = jiffies;
 795         }
 796
 797         if (lp->cur_tx == -1)
 798                 netif_wake_queue(dev);
 799 }
 800 EXPORT_SYMBOL(arcnet_timeout);
 801
 802 /* The typical workload of the driver: Handle the network interface
 803  * interrupts. Establish which device needs attention, and call the correct
 804  * chipset interrupt handler.
 805  */
 806 irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 807 {
 808         struct net_device *dev = dev_id;
 809         struct arcnet_local *lp;
 810         int recbuf, status, diagstatus, didsomething, boguscount;
 811         unsigned long flags;
 812         int retval = IRQ_NONE;
 813
 814         arc_printk(D_DURING, dev, "\n");
 815
 816         arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
 817
 818         lp = netdev_priv(dev);
 819         BUG_ON(!lp);
 820
 821         spin_lock_irqsave(&lp->lock, flags);
 822
 823         /* RESET flag was enabled - if device is not running, we must
 824          * clear it right away (but nothing else).
 825          */
 826         if (!netif_running(dev)) {
 827                 if (lp->hw.status(dev) & RESETflag)
 828                         lp->hw.command(dev, CFLAGScmd | RESETclear);
 829                 lp->hw.intmask(dev, 0);
 830                 spin_unlock_irqrestore(&lp->lock, flags);
 831                 return retval;
 832         }
 833
 834         arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 835                    lp->hw.status(dev), lp->intmask);
 836
 837         boguscount = 5;
 838         do {
 839                 status = lp->hw.status(dev);
 840                 diagstatus = (status >> 8) & 0xFF;
 841
 842                 arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
 843                            __FILE__, __LINE__, __func__, status);
 844                 didsomething = 0;
 845
 846                 /* RESET flag was enabled - card is resetting and if RX is
 847                  * disabled, it's NOT because we just got a packet.
 848                  *
 849                  * The card is in an undefined state.
 850                  * Clear it out and start over.
 851                  */
 852                 if (status & RESETflag) {
 853                         arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 854                                    status);
 855                         arcnet_close(dev);
 856                         arcnet_open(dev);
 857
 858                         /* get out of the interrupt handler! */
 859                         break;
 860                 }
 861                 /* RX is inhibited - we must have received something.
 862                  * Prepare to receive into the next buffer.
 863                  *
 864                  * We don't actually copy the received packet from the card
 865                  * until after the transmit handler runs (and possibly
 866                  * launches the next tx); this should improve latency slightly
 867                  * if we get both types of interrupts at once.
 868                  */
 869                 recbuf = -1;
 870                 if (status & lp->intmask & NORXflag) {
 871                         recbuf = lp->cur_rx;
 872                         arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
 873                                    recbuf, status);
 874
 875                         lp->cur_rx = get_arcbuf(dev);
 876                         if (lp->cur_rx != -1) {
 877                                 arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
 878                                            lp->cur_rx);
 879                                 lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
 880                         }
 881                         didsomething++;
 882                 }
 883
 884                 if ((diagstatus & EXCNAKflag)) {
 885                         arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
 886                                    diagstatus);
 887
 888                         lp->hw.command(dev, NOTXcmd);      /* disable transmit */
 889                         lp->excnak_pending = 1;
 890
 891                         lp->hw.command(dev, EXCNAKclear);
 892                         lp->intmask &= ~(EXCNAKflag);
 893                         didsomething++;
 894                 }
 895
 896                 /* a transmit finished, and we're interested in it. */
 897                 if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 898                         int ackstatus;
 899                         lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 900
 901                         if (status & TXACKflag)
 902                                 ackstatus = 2;
 903                         else if (lp->excnak_pending)
 904                                 ackstatus = 1;
 905                         else
 906                                 ackstatus = 0;
 907
 908                         arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
 909                                    status);
 910
 911                         if (lp->cur_tx != -1 && !lp->timed_out) {
 912                                 if (!(status & TXACKflag)) {
 913                                         if (lp->lasttrans_dest != 0) {
 914                                                 arc_printk(D_EXTRA, dev,
 915                                                            "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
 916                                                            status,
 917                                                            lp->lasttrans_dest);
 918                                                 dev->stats.tx_errors++;
 919                                                 dev->stats.tx_carrier_errors++;
 920                                         } else {
 921                                                 arc_printk(D_DURING, dev,
 922                                                            "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
 923                                                            status,
 924                                                            lp->lasttrans_dest);
 925                                         }
 926                                 }
 927
 928                                 if (lp->outgoing.proto &&
 929                                     lp->outgoing.proto->ack_tx) {
 930                                         lp->outgoing.proto
 931                                                 ->ack_tx(dev, ackstatus);
 932                                 }
 933                                 lp->reply_status = ackstatus;
 934                                 tasklet_hi_schedule(&lp->reply_tasklet);
 935                         }
 936                         if (lp->cur_tx != -1)
 937                                 release_arcbuf(dev, lp->cur_tx);
 938
 939                         lp->cur_tx = -1;
 940                         lp->timed_out = 0;
 941                         didsomething++;
 942
 943                         /* send another packet if there is one */
 944                         go_tx(dev);
 945
 946                         /* continue a split packet, if any */
 947                         if (lp->outgoing.proto &&
 948                             lp->outgoing.proto->continue_tx) {
 949                                 int txbuf = get_arcbuf(dev);
 950
 951                                 if (txbuf != -1) {
 952                                         if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
 953                                                 /* that was the last segment */
 954                                                 dev->stats.tx_bytes += lp->outgoing.skb->len;
 955                                                 if (!lp->outgoing.proto->ack_tx) {
 956                                                         dev_kfree_skb_irq(lp->outgoing.skb);
 957                                                         lp->outgoing.proto = NULL;
 958                                                 }
 959                                         }
 960                                         lp->next_tx = txbuf;
 961                                 }
 962                         }
 963                         /* inform upper layers of idleness, if necessary */
 964                         if (lp->cur_tx == -1)
 965                                 netif_wake_queue(dev);
 966                 }
 967                 /* now process the received packet, if any */
 968                 if (recbuf != -1) {
 969                         if (BUGLVL(D_RX))
 970                                 arcnet_dump_packet(dev, recbuf, "rx irq", 0);
 971
 972                         arcnet_rx(dev, recbuf);
 973                         release_arcbuf(dev, recbuf);
 974
 975                         didsomething++;
 976                 }
 977                 if (status & lp->intmask & RECONflag) {
 978                         lp->hw.command(dev, CFLAGScmd | CONFIGclear);
 979                         dev->stats.tx_carrier_errors++;
 980
 981                         arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
 982                                    status);
 983                         if (netif_carrier_ok(dev)) {
 984                                 netif_carrier_off(dev);
 985                                 netdev_info(dev, "link down\n");
 986                         }
 987                         mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 988
 989                         arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
 990                         /* MYRECON bit is at bit 7 of diagstatus */
 991                         if (diagstatus & 0x80)
 992                                 arc_printk(D_RECON, dev, "Put out that recon myself\n");
 993
 994                         /* is the RECON info empty or old? */
 995                         if (!lp->first_recon || !lp->last_recon ||
 996                             time_after(jiffies, lp->last_recon + HZ * 10)) {
 997                                 if (lp->network_down)
 998                                         arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
 999                                 lp->first_recon = lp->last_recon = jiffies;
1000                                 lp->num_recons = lp->network_down = 0;
1001
1002                                 arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1003                         } else {        /* add to current RECON counter */
1004                                 lp->last_recon = jiffies;
1005                                 lp->num_recons++;
1006
1007                                 arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1008                                            lp->num_recons,
1009                                            (lp->last_recon - lp->first_recon) / HZ,
1010                                            lp->network_down);
1011
1012                                 /* if network is marked up;
1013                                  * and first_recon and last_recon are 60+ apart;
1014                                  * and the average no. of recons counted is
1015                                  *    > RECON_THRESHOLD/min;
1016                                  * then print a warning message.
1017                                  */
1018                                 if (!lp->network_down &&
1019                                     (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1020                                     lp->num_recons >= RECON_THRESHOLD) {
1021                                         lp->network_down = 1;
1022                                         arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1023                                 } else if (!lp->network_down &&
1024                                            lp->last_recon - lp->first_recon > HZ * 60) {
1025                                         /* reset counters if we've gone for
1026                                          *  over a minute.
1027                                          */
1028                                         lp->first_recon = lp->last_recon;
1029                                         lp->num_recons = 1;
1030                                 }
1031                         }
1032                 } else if (lp->network_down &&
1033                            time_after(jiffies, lp->last_recon + HZ * 10)) {
1034                         if (lp->network_down)
1035                                 arc_printk(D_NORMAL, dev, "cabling restored?\n");
1036                         lp->first_recon = lp->last_recon = 0;
1037                         lp->num_recons = lp->network_down = 0;
1038
1039                         arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1040                         netif_carrier_on(dev);
1041                 }
1042
1043                 if (didsomething)
1044                         retval |= IRQ_HANDLED;
1045         } while (--boguscount && didsomething);
1046
1047         arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1048                    lp->hw.status(dev), boguscount);
1049         arc_printk(D_DURING, dev, "\n");
1050
1051         lp->hw.intmask(dev, 0);
1052         udelay(1);
1053         lp->hw.intmask(dev, lp->intmask);
1054
1055         spin_unlock_irqrestore(&lp->lock, flags);
1056         return retval;
1057 }
1058 EXPORT_SYMBOL(arcnet_interrupt);
1059
1060 /* This is a generic packet receiver that calls arcnet??_rx depending on the
1061  * protocol ID found.
1062  */
1063 static void arcnet_rx(struct net_device *dev, int bufnum)
1064 {
1065         struct arcnet_local *lp = netdev_priv(dev);
1066         union {
1067                 struct archdr pkt;
1068                 char buf[512];
1069         } rxdata;
1070         struct arc_rfc1201 *soft;
1071         int length, ofs;
1072
1073         soft = &rxdata.pkt.soft.rfc1201;
1074
1075         lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1076         if (rxdata.pkt.hard.offset[0]) {
1077                 ofs = rxdata.pkt.hard.offset[0];
1078                 length = 256 - ofs;
1079         } else {
1080                 ofs = rxdata.pkt.hard.offset[1];
1081                 length = 512 - ofs;
1082         }
1083
1084         /* get the full header, if possible */
1085         if (sizeof(rxdata.pkt.soft) <= length) {
1086                 lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1087         } else {
1088                 memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1089                 lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1090         }
1091
1092         arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1093                    bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1094
1095         dev->stats.rx_packets++;
1096         dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1097
1098         /* call the right receiver for the protocol */
1099         if (arc_proto_map[soft->proto]->is_ip) {
1100                 if (BUGLVL(D_PROTO)) {
1101                         struct ArcProto
1102                         *oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1103                         *newp = arc_proto_map[soft->proto];
1104
1105                         if (oldp != newp) {
1106                                 arc_printk(D_PROTO, dev,
1107                                            "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1108                                            soft->proto, rxdata.pkt.hard.source,
1109                                            newp->suffix, oldp->suffix);
1110                         }
1111                 }
1112
1113                 /* broadcasts will always be done with the last-used encap. */
1114                 lp->default_proto[0] = soft->proto;
1115
1116                 /* in striking contrast, the following isn't a hack. */
1117                 lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1118         }
1119         /* call the protocol-specific receiver. */
1120         arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1121 }
1122
1123 static void null_rx(struct net_device *dev, int bufnum,
1124                     struct archdr *pkthdr, int length)
1125 {
1126         arc_printk(D_PROTO, dev,
1127                    "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1128                    pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1129 }
1130
1131 static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1132                              unsigned short type, uint8_t daddr)
1133 {
1134         struct arcnet_local *lp = netdev_priv(dev);
1135
1136         arc_printk(D_PROTO, dev,
1137                    "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1138                    lp->default_proto[daddr]);
1139
1140         /* always fails */
1141         return 0;
1142 }
1143
1144 /* the "do nothing" prepare_tx function warns that there's nothing to do. */
1145 static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1146                            int length, int bufnum)
1147 {
1148         struct arcnet_local *lp = netdev_priv(dev);
1149         struct arc_hardware newpkt;
1150
1151         arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1152
1153         /* send a packet to myself -- will never get received, of course */
1154         newpkt.source = newpkt.dest = dev->dev_addr[0];
1155
1156         /* only one byte of actual data (and it's random) */
1157         newpkt.offset[0] = 0xFF;
1158
1159         lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1160
1161         return 1;               /* done */
1162 }