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