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v6.8
   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 */
  62static void null_rx(struct net_device *dev, int bufnum,
  63		    struct archdr *pkthdr, int length);
  64static int null_build_header(struct sk_buff *skb, struct net_device *dev,
  65			     unsigned short type, uint8_t daddr);
  66static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
  67			   int length, int bufnum);
  68
  69static 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 */
  76struct ArcProto *arc_proto_map[256];
  77EXPORT_SYMBOL(arc_proto_map);
  78
  79struct ArcProto *arc_proto_default;
  80EXPORT_SYMBOL(arc_proto_default);
  81
  82struct ArcProto *arc_bcast_proto;
  83EXPORT_SYMBOL(arc_bcast_proto);
  84
  85struct ArcProto *arc_raw_proto;
  86EXPORT_SYMBOL(arc_raw_proto);
  87
  88static 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 */
 100int arcnet_debug = ARCNET_DEBUG;
 101EXPORT_SYMBOL(arcnet_debug);
 102
 103/* Internal function prototypes */
 104static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 105			 unsigned short type, const void *daddr,
 106			 const void *saddr, unsigned len);
 107static int go_tx(struct net_device *dev);
 108
 109static int debug = ARCNET_DEBUG;
 110module_param(debug, int, 0);
 111MODULE_LICENSE("GPL");
 112
 113static 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
 137static void __exit arcnet_exit(void)
 138{
 139}
 140
 141module_init(arcnet_init);
 142module_exit(arcnet_exit);
 143
 144/* Dump the contents of an sk_buff */
 145#if ARCNET_DEBUG_MAX & D_SKB
 146void 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}
 156EXPORT_SYMBOL(arcnet_dump_skb);
 157#endif
 158
 159/* Dump the contents of an ARCnet buffer */
 160#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 161static 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 */
 196void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
 197{
 198	struct arcnet_local *lp = netdev_priv(dev);
 
 
 199
 200	switch (event) {
 201	case ARCNET_LED_EVENT_RECON:
 202		led_trigger_blink_oneshot(lp->recon_led_trig, 350, 350, 0);
 
 203		break;
 204	case ARCNET_LED_EVENT_OPEN:
 205		led_trigger_event(lp->tx_led_trig, LED_OFF);
 206		led_trigger_event(lp->recon_led_trig, LED_OFF);
 207		break;
 208	case ARCNET_LED_EVENT_STOP:
 209		led_trigger_event(lp->tx_led_trig, LED_OFF);
 210		led_trigger_event(lp->recon_led_trig, LED_OFF);
 211		break;
 212	case ARCNET_LED_EVENT_TX:
 213		led_trigger_blink_oneshot(lp->tx_led_trig, 50, 50, 0);
 
 214		break;
 215	}
 216}
 217EXPORT_SYMBOL_GPL(arcnet_led_event);
 218
 219static void arcnet_led_release(struct device *gendev, void *res)
 220{
 221	struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
 222
 223	led_trigger_unregister_simple(lp->tx_led_trig);
 224	led_trigger_unregister_simple(lp->recon_led_trig);
 225}
 226
 227/* Register ARCNET LED triggers for a arcnet device
 228 *
 229 * This is normally called from a driver's probe function
 230 */
 231void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
 232{
 233	struct arcnet_local *lp = netdev_priv(netdev);
 234	void *res;
 235
 236	res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
 237	if (!res) {
 238		netdev_err(netdev, "cannot register LED triggers\n");
 239		return;
 240	}
 241
 242	snprintf(lp->tx_led_trig_name, sizeof(lp->tx_led_trig_name),
 243		 "arc%d-%d-tx", index, subid);
 244	snprintf(lp->recon_led_trig_name, sizeof(lp->recon_led_trig_name),
 245		 "arc%d-%d-recon", index, subid);
 246
 247	led_trigger_register_simple(lp->tx_led_trig_name,
 248				    &lp->tx_led_trig);
 249	led_trigger_register_simple(lp->recon_led_trig_name,
 250				    &lp->recon_led_trig);
 251
 252	devres_add(&netdev->dev, res);
 253}
 254EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
 255
 256/* Unregister a protocol driver from the arc_proto_map.  Protocol drivers
 257 * are responsible for registering themselves, but the unregister routine
 258 * is pretty generic so we'll do it here.
 259 */
 260void arcnet_unregister_proto(struct ArcProto *proto)
 261{
 262	int count;
 263
 264	if (arc_proto_default == proto)
 265		arc_proto_default = &arc_proto_null;
 266	if (arc_bcast_proto == proto)
 267		arc_bcast_proto = arc_proto_default;
 268	if (arc_raw_proto == proto)
 269		arc_raw_proto = arc_proto_default;
 270
 271	for (count = 0; count < 256; count++) {
 272		if (arc_proto_map[count] == proto)
 273			arc_proto_map[count] = arc_proto_default;
 274	}
 275}
 276EXPORT_SYMBOL(arcnet_unregister_proto);
 277
 278/* Add a buffer to the queue.  Only the interrupt handler is allowed to do
 279 * this, unless interrupts are disabled.
 280 *
 281 * Note: we don't check for a full queue, since there aren't enough buffers
 282 * to more than fill it.
 283 */
 284static void release_arcbuf(struct net_device *dev, int bufnum)
 285{
 286	struct arcnet_local *lp = netdev_priv(dev);
 287	int i;
 288
 289	lp->buf_queue[lp->first_free_buf++] = bufnum;
 290	lp->first_free_buf %= 5;
 291
 292	if (BUGLVL(D_DURING)) {
 293		arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
 294			   bufnum);
 295		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 296			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 297		arc_cont(D_DURING, "\n");
 298	}
 299}
 300
 301/* Get a buffer from the queue.
 302 * If this returns -1, there are no buffers available.
 303 */
 304static int get_arcbuf(struct net_device *dev)
 305{
 306	struct arcnet_local *lp = netdev_priv(dev);
 307	int buf = -1, i;
 308
 309	if (!atomic_dec_and_test(&lp->buf_lock)) {
 310		/* already in this function */
 311		arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
 312			   lp->buf_lock.counter);
 313	} else {			/* we can continue */
 314		if (lp->next_buf >= 5)
 315			lp->next_buf -= 5;
 316
 317		if (lp->next_buf == lp->first_free_buf) {
 318			arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
 319		} else {
 320			buf = lp->buf_queue[lp->next_buf++];
 321			lp->next_buf %= 5;
 322		}
 323	}
 324
 325	if (BUGLVL(D_DURING)) {
 326		arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
 327			   buf);
 328		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 329			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 330		arc_cont(D_DURING, "\n");
 331	}
 332
 333	atomic_inc(&lp->buf_lock);
 334	return buf;
 335}
 336
 337static int choose_mtu(void)
 338{
 339	int count, mtu = 65535;
 340
 341	/* choose the smallest MTU of all available encaps */
 342	for (count = 0; count < 256; count++) {
 343		if (arc_proto_map[count] != &arc_proto_null &&
 344		    arc_proto_map[count]->mtu < mtu) {
 345			mtu = arc_proto_map[count]->mtu;
 346		}
 347	}
 348
 349	return mtu == 65535 ? XMTU : mtu;
 350}
 351
 352static const struct header_ops arcnet_header_ops = {
 353	.create = arcnet_header,
 354};
 355
 356static const struct net_device_ops arcnet_netdev_ops = {
 357	.ndo_open	= arcnet_open,
 358	.ndo_stop	= arcnet_close,
 359	.ndo_start_xmit = arcnet_send_packet,
 360	.ndo_tx_timeout = arcnet_timeout,
 361};
 362
 363/* Setup a struct device for ARCnet. */
 364static void arcdev_setup(struct net_device *dev)
 365{
 366	dev->type = ARPHRD_ARCNET;
 367	dev->netdev_ops = &arcnet_netdev_ops;
 368	dev->header_ops = &arcnet_header_ops;
 369	dev->hard_header_len = sizeof(struct arc_hardware);
 370	dev->mtu = choose_mtu();
 371
 372	dev->addr_len = ARCNET_ALEN;
 373	dev->tx_queue_len = 100;
 374	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
 375	dev->watchdog_timeo = TX_TIMEOUT;
 376
 377	/* New-style flags. */
 378	dev->flags = IFF_BROADCAST;
 379}
 380
 381static void arcnet_timer(struct timer_list *t)
 382{
 383	struct arcnet_local *lp = from_timer(lp, t, timer);
 384	struct net_device *dev = lp->dev;
 385
 386	spin_lock_irq(&lp->lock);
 387
 388	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
 389		netif_carrier_on(dev);
 390		netdev_info(dev, "link up\n");
 391	}
 392
 393	spin_unlock_irq(&lp->lock);
 394}
 395
 396static void reset_device_work(struct work_struct *work)
 397{
 398	struct arcnet_local *lp;
 399	struct net_device *dev;
 400
 401	lp = container_of(work, struct arcnet_local, reset_work);
 402	dev = lp->dev;
 403
 404	/* Do not bring the network interface back up if an ifdown
 405	 * was already done.
 406	 */
 407	if (!netif_running(dev) || !lp->reset_in_progress)
 408		return;
 409
 410	rtnl_lock();
 411
 412	/* Do another check, in case of an ifdown that was triggered in
 413	 * the small race window between the exit condition above and
 414	 * acquiring RTNL.
 415	 */
 416	if (!netif_running(dev) || !lp->reset_in_progress)
 417		goto out;
 418
 419	dev_close(dev);
 420	dev_open(dev, NULL);
 421
 422out:
 423	rtnl_unlock();
 424}
 425
 426static void arcnet_reply_tasklet(struct tasklet_struct *t)
 427{
 428	struct arcnet_local *lp = from_tasklet(lp, t, reply_tasklet);
 429
 430	struct sk_buff *ackskb, *skb;
 431	struct sock_exterr_skb *serr;
 432	struct sock *sk;
 433	int ret;
 434
 435	local_irq_disable();
 436	skb = lp->outgoing.skb;
 437	if (!skb || !skb->sk) {
 438		local_irq_enable();
 439		return;
 440	}
 441
 442	sock_hold(skb->sk);
 443	sk = skb->sk;
 444	ackskb = skb_clone_sk(skb);
 445	sock_put(skb->sk);
 446
 447	if (!ackskb) {
 448		local_irq_enable();
 449		return;
 450	}
 451
 452	serr = SKB_EXT_ERR(ackskb);
 453	memset(serr, 0, sizeof(*serr));
 454	serr->ee.ee_errno = ENOMSG;
 455	serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
 456	serr->ee.ee_data = skb_shinfo(skb)->tskey;
 457	serr->ee.ee_info = lp->reply_status;
 458
 459	/* finally erasing outgoing skb */
 460	dev_kfree_skb(lp->outgoing.skb);
 461	lp->outgoing.skb = NULL;
 462
 463	ackskb->dev = lp->dev;
 464
 465	ret = sock_queue_err_skb(sk, ackskb);
 466	if (ret)
 467		dev_kfree_skb_irq(ackskb);
 468
 469	local_irq_enable();
 470};
 471
 472struct net_device *alloc_arcdev(const char *name)
 473{
 474	struct net_device *dev;
 475
 476	dev = alloc_netdev(sizeof(struct arcnet_local),
 477			   name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
 478			   arcdev_setup);
 479	if (dev) {
 480		struct arcnet_local *lp = netdev_priv(dev);
 481
 482		lp->dev = dev;
 483		spin_lock_init(&lp->lock);
 484		timer_setup(&lp->timer, arcnet_timer, 0);
 485		INIT_WORK(&lp->reset_work, reset_device_work);
 486	}
 487
 488	return dev;
 489}
 490EXPORT_SYMBOL(alloc_arcdev);
 491
 492void free_arcdev(struct net_device *dev)
 493{
 494	struct arcnet_local *lp = netdev_priv(dev);
 495
 496	/* Do not cancel this at ->ndo_close(), as the workqueue itself
 497	 * indirectly calls the ifdown path through dev_close().
 498	 */
 499	cancel_work_sync(&lp->reset_work);
 500	free_netdev(dev);
 501}
 502EXPORT_SYMBOL(free_arcdev);
 503
 504/* Open/initialize the board.  This is called sometime after booting when
 505 * the 'ifconfig' program is run.
 506 *
 507 * This routine should set everything up anew at each open, even registers
 508 * that "should" only need to be set once at boot, so that there is
 509 * non-reboot way to recover if something goes wrong.
 510 */
 511int arcnet_open(struct net_device *dev)
 512{
 513	struct arcnet_local *lp = netdev_priv(dev);
 514	int count, newmtu, error;
 515
 516	arc_printk(D_INIT, dev, "opened.");
 517
 518	if (!try_module_get(lp->hw.owner))
 519		return -ENODEV;
 520
 521	if (BUGLVL(D_PROTO)) {
 522		arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
 523			   arc_proto_default->suffix);
 524		for (count = 0; count < 256; count++)
 525			arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
 526		arc_cont(D_PROTO, "\n");
 527	}
 528
 529	tasklet_setup(&lp->reply_tasklet, arcnet_reply_tasklet);
 
 530
 531	arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 532
 533	/* try to put the card in a defined state - if it fails the first
 534	 * time, actually reset it.
 535	 */
 536	error = -ENODEV;
 537	if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
 538		goto out_module_put;
 539
 540	newmtu = choose_mtu();
 541	if (newmtu < dev->mtu)
 542		dev->mtu = newmtu;
 543
 544	arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
 545
 546	/* autodetect the encapsulation for each host. */
 547	memset(lp->default_proto, 0, sizeof(lp->default_proto));
 548
 549	/* the broadcast address is special - use the 'bcast' protocol */
 550	for (count = 0; count < 256; count++) {
 551		if (arc_proto_map[count] == arc_bcast_proto) {
 552			lp->default_proto[0] = count;
 553			break;
 554		}
 555	}
 556
 557	/* initialize buffers */
 558	atomic_set(&lp->buf_lock, 1);
 559
 560	lp->next_buf = lp->first_free_buf = 0;
 561	release_arcbuf(dev, 0);
 562	release_arcbuf(dev, 1);
 563	release_arcbuf(dev, 2);
 564	release_arcbuf(dev, 3);
 565	lp->cur_tx = lp->next_tx = -1;
 566	lp->cur_rx = -1;
 567
 568	lp->rfc1201.sequence = 1;
 569
 570	/* bring up the hardware driver */
 571	if (lp->hw.open)
 572		lp->hw.open(dev);
 573
 574	if (dev->dev_addr[0] == 0)
 575		arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
 576	else if (dev->dev_addr[0] == 255)
 577		arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
 578
 579	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 580	if (lp->hw.status(dev) & RESETflag) {
 581		arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
 582			   __FILE__, __LINE__, __func__);
 583		lp->hw.command(dev, CFLAGScmd | RESETclear);
 584	}
 585
 586	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 587	/* make sure we're ready to receive IRQ's. */
 588	lp->hw.intmask(dev, 0);
 589	udelay(1);		/* give it time to set the mask before
 590				 * we reset it again. (may not even be
 591				 * necessary)
 592				 */
 593	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 594	lp->intmask = NORXflag | RECONflag;
 595	lp->hw.intmask(dev, lp->intmask);
 596	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 597
 598	netif_carrier_off(dev);
 599	netif_start_queue(dev);
 600	mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 601
 602	arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
 603	return 0;
 604
 605 out_module_put:
 606	module_put(lp->hw.owner);
 607	return error;
 608}
 609EXPORT_SYMBOL(arcnet_open);
 610
 611/* The inverse routine to arcnet_open - shuts down the card. */
 612int arcnet_close(struct net_device *dev)
 613{
 614	struct arcnet_local *lp = netdev_priv(dev);
 615
 616	arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
 617	del_timer_sync(&lp->timer);
 618
 619	netif_stop_queue(dev);
 620	netif_carrier_off(dev);
 621
 622	tasklet_kill(&lp->reply_tasklet);
 623
 624	/* flush TX and disable RX */
 625	lp->hw.intmask(dev, 0);
 626	lp->hw.command(dev, NOTXcmd);	/* stop transmit */
 627	lp->hw.command(dev, NORXcmd);	/* disable receive */
 628	mdelay(1);
 629
 630	/* shut down the card */
 631	lp->hw.close(dev);
 632
 633	/* reset counters */
 634	lp->reset_in_progress = 0;
 635
 636	module_put(lp->hw.owner);
 637	return 0;
 638}
 639EXPORT_SYMBOL(arcnet_close);
 640
 641static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 642			 unsigned short type, const void *daddr,
 643			 const void *saddr, unsigned len)
 644{
 645	const struct arcnet_local *lp = netdev_priv(dev);
 646	uint8_t _daddr, proto_num;
 647	struct ArcProto *proto;
 648
 649	arc_printk(D_DURING, dev,
 650		   "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 651		   saddr ? *(uint8_t *)saddr : -1,
 652		   daddr ? *(uint8_t *)daddr : -1,
 653		   type, type, len);
 654
 655	if (skb->len != 0 && len != skb->len)
 656		arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 657			   skb->len, len);
 658
 659	/* Type is host order - ? */
 660	if (type == ETH_P_ARCNET) {
 661		proto = arc_raw_proto;
 662		arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
 663			   proto->suffix);
 664		_daddr = daddr ? *(uint8_t *)daddr : 0;
 665	} else if (!daddr) {
 666		/* if the dest addr isn't provided, we can't choose an
 667		 * encapsulation!  Store the packet type (eg. ETH_P_IP)
 668		 * for now, and we'll push on a real header when we do
 669		 * rebuild_header.
 670		 */
 671		*(uint16_t *)skb_push(skb, 2) = type;
 672		/* XXX: Why not use skb->mac_len? */
 673		if (skb->network_header - skb->mac_header != 2)
 674			arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
 675				   skb->network_header - skb->mac_header);
 676		return -2;	/* return error -- can't transmit yet! */
 677	} else {
 678		/* otherwise, we can just add the header as usual. */
 679		_daddr = *(uint8_t *)daddr;
 680		proto_num = lp->default_proto[_daddr];
 681		proto = arc_proto_map[proto_num];
 682		arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
 683			   proto_num, proto->suffix);
 684		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 685			arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
 686				   arc_bcast_proto->suffix);
 687			proto = arc_bcast_proto;
 688		}
 689	}
 690	return proto->build_header(skb, dev, type, _daddr);
 691}
 692
 693/* Called by the kernel in order to transmit a packet. */
 694netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 695			       struct net_device *dev)
 696{
 697	struct arcnet_local *lp = netdev_priv(dev);
 698	struct archdr *pkt;
 699	struct arc_rfc1201 *soft;
 700	struct ArcProto *proto;
 701	int txbuf;
 702	unsigned long flags;
 703	int retval;
 704
 705	arc_printk(D_DURING, dev,
 706		   "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 707		   lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
 708
 709	pkt = (struct archdr *)skb->data;
 710	soft = &pkt->soft.rfc1201;
 711	proto = arc_proto_map[soft->proto];
 712
 713	arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
 714		   skb->len, pkt->hard.dest);
 715	if (BUGLVL(D_SKB))
 716		arcnet_dump_skb(dev, skb, "tx");
 717
 718	/* fits in one packet? */
 719	if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 720		arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
 721		dev_kfree_skb(skb);
 722		return NETDEV_TX_OK;	/* don't try again */
 723	}
 724
 725	/* We're busy transmitting a packet... */
 726	netif_stop_queue(dev);
 727
 728	spin_lock_irqsave(&lp->lock, flags);
 729	lp->hw.intmask(dev, 0);
 730	if (lp->next_tx == -1)
 731		txbuf = get_arcbuf(dev);
 732	else
 733		txbuf = -1;
 734
 735	if (txbuf != -1) {
 736		lp->outgoing.skb = skb;
 737		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 738		    !proto->ack_tx) {
 739			/* done right away and we don't want to acknowledge
 740			 *  the package later - forget about it now
 741			 */
 742			dev->stats.tx_bytes += skb->len;
 743		} else {
 744			/* do it the 'split' way */
 745			lp->outgoing.proto = proto;
 746			lp->outgoing.skb = skb;
 747			lp->outgoing.pkt = pkt;
 748
 749			if (proto->continue_tx &&
 750			    proto->continue_tx(dev, txbuf)) {
 751				arc_printk(D_NORMAL, dev,
 752					   "bug! continue_tx finished the first time! (proto='%c')\n",
 753					   proto->suffix);
 754			}
 755		}
 756		retval = NETDEV_TX_OK;
 757		lp->next_tx = txbuf;
 758	} else {
 759		retval = NETDEV_TX_BUSY;
 760	}
 761
 762	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 763		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 764	/* make sure we didn't ignore a TX IRQ while we were in here */
 765	lp->hw.intmask(dev, 0);
 766
 767	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 768	lp->intmask |= TXFREEflag | EXCNAKflag;
 769	lp->hw.intmask(dev, lp->intmask);
 770	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 771		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 772
 773	arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
 774
 775	spin_unlock_irqrestore(&lp->lock, flags);
 776	return retval;		/* no need to try again */
 777}
 778EXPORT_SYMBOL(arcnet_send_packet);
 779
 780/* Actually start transmitting a packet that was loaded into a buffer
 781 * by prepare_tx.  This should _only_ be called by the interrupt handler.
 782 */
 783static int go_tx(struct net_device *dev)
 784{
 785	struct arcnet_local *lp = netdev_priv(dev);
 786
 787	arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 788		   lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
 789
 790	if (lp->cur_tx != -1 || lp->next_tx == -1)
 791		return 0;
 792
 793	if (BUGLVL(D_TX))
 794		arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 795
 796	lp->cur_tx = lp->next_tx;
 797	lp->next_tx = -1;
 798
 799	/* start sending */
 800	lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
 801
 802	dev->stats.tx_packets++;
 803	lp->lasttrans_dest = lp->lastload_dest;
 804	lp->lastload_dest = 0;
 805	lp->excnak_pending = 0;
 806	lp->intmask |= TXFREEflag | EXCNAKflag;
 807
 808	return 1;
 809}
 810
 811/* Called by the kernel when transmit times out */
 812void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
 813{
 814	unsigned long flags;
 815	struct arcnet_local *lp = netdev_priv(dev);
 816	int status = lp->hw.status(dev);
 817	char *msg;
 818
 819	spin_lock_irqsave(&lp->lock, flags);
 820	if (status & TXFREEflag) {	/* transmit _DID_ finish */
 821		msg = " - missed IRQ?";
 822	} else {
 823		msg = "";
 824		dev->stats.tx_aborted_errors++;
 825		lp->timed_out = 1;
 826		lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
 827	}
 828	dev->stats.tx_errors++;
 829
 830	/* make sure we didn't miss a TX or a EXC NAK IRQ */
 831	lp->hw.intmask(dev, 0);
 832	lp->intmask |= TXFREEflag | EXCNAKflag;
 833	lp->hw.intmask(dev, lp->intmask);
 834
 835	spin_unlock_irqrestore(&lp->lock, flags);
 836
 837	if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
 838		arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 839			   msg, status, lp->intmask, lp->lasttrans_dest);
 840		lp->last_timeout = jiffies;
 841	}
 842
 843	if (lp->cur_tx == -1)
 844		netif_wake_queue(dev);
 845}
 846EXPORT_SYMBOL(arcnet_timeout);
 847
 848/* The typical workload of the driver: Handle the network interface
 849 * interrupts. Establish which device needs attention, and call the correct
 850 * chipset interrupt handler.
 851 */
 852irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 853{
 854	struct net_device *dev = dev_id;
 855	struct arcnet_local *lp;
 856	int recbuf, status, diagstatus, didsomething, boguscount;
 857	unsigned long flags;
 858	int retval = IRQ_NONE;
 859
 860	arc_printk(D_DURING, dev, "\n");
 861
 862	arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
 863
 864	lp = netdev_priv(dev);
 865	BUG_ON(!lp);
 866
 867	spin_lock_irqsave(&lp->lock, flags);
 868
 869	if (lp->reset_in_progress)
 870		goto out;
 871
 872	/* RESET flag was enabled - if device is not running, we must
 873	 * clear it right away (but nothing else).
 874	 */
 875	if (!netif_running(dev)) {
 876		if (lp->hw.status(dev) & RESETflag)
 877			lp->hw.command(dev, CFLAGScmd | RESETclear);
 878		lp->hw.intmask(dev, 0);
 879		spin_unlock_irqrestore(&lp->lock, flags);
 880		return retval;
 881	}
 882
 883	arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 884		   lp->hw.status(dev), lp->intmask);
 885
 886	boguscount = 5;
 887	do {
 888		status = lp->hw.status(dev);
 889		diagstatus = (status >> 8) & 0xFF;
 890
 891		arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
 892			   __FILE__, __LINE__, __func__, status);
 893		didsomething = 0;
 894
 895		/* RESET flag was enabled - card is resetting and if RX is
 896		 * disabled, it's NOT because we just got a packet.
 897		 *
 898		 * The card is in an undefined state.
 899		 * Clear it out and start over.
 900		 */
 901		if (status & RESETflag) {
 902			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 903				   status);
 904
 905			lp->reset_in_progress = 1;
 906			netif_stop_queue(dev);
 907			netif_carrier_off(dev);
 908			schedule_work(&lp->reset_work);
 909
 910			/* get out of the interrupt handler! */
 911			goto out;
 912		}
 913		/* RX is inhibited - we must have received something.
 914		 * Prepare to receive into the next buffer.
 915		 *
 916		 * We don't actually copy the received packet from the card
 917		 * until after the transmit handler runs (and possibly
 918		 * launches the next tx); this should improve latency slightly
 919		 * if we get both types of interrupts at once.
 920		 */
 921		recbuf = -1;
 922		if (status & lp->intmask & NORXflag) {
 923			recbuf = lp->cur_rx;
 924			arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
 925				   recbuf, status);
 926
 927			lp->cur_rx = get_arcbuf(dev);
 928			if (lp->cur_rx != -1) {
 929				arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
 930					   lp->cur_rx);
 931				lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
 932			}
 933			didsomething++;
 934		}
 935
 936		if ((diagstatus & EXCNAKflag)) {
 937			arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
 938				   diagstatus);
 939
 940			lp->hw.command(dev, NOTXcmd);      /* disable transmit */
 941			lp->excnak_pending = 1;
 942
 943			lp->hw.command(dev, EXCNAKclear);
 944			lp->intmask &= ~(EXCNAKflag);
 945			didsomething++;
 946		}
 947
 948		/* a transmit finished, and we're interested in it. */
 949		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 950			int ackstatus;
 951			lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 952
 953			if (status & TXACKflag)
 954				ackstatus = 2;
 955			else if (lp->excnak_pending)
 956				ackstatus = 1;
 957			else
 958				ackstatus = 0;
 959
 960			arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
 961				   status);
 962
 963			if (lp->cur_tx != -1 && !lp->timed_out) {
 964				if (!(status & TXACKflag)) {
 965					if (lp->lasttrans_dest != 0) {
 966						arc_printk(D_EXTRA, dev,
 967							   "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
 968							   status,
 969							   lp->lasttrans_dest);
 970						dev->stats.tx_errors++;
 971						dev->stats.tx_carrier_errors++;
 972					} else {
 973						arc_printk(D_DURING, dev,
 974							   "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
 975							   status,
 976							   lp->lasttrans_dest);
 977					}
 978				}
 979
 980				if (lp->outgoing.proto &&
 981				    lp->outgoing.proto->ack_tx) {
 982					lp->outgoing.proto
 983						->ack_tx(dev, ackstatus);
 984				}
 985				lp->reply_status = ackstatus;
 986				tasklet_hi_schedule(&lp->reply_tasklet);
 987			}
 988			if (lp->cur_tx != -1)
 989				release_arcbuf(dev, lp->cur_tx);
 990
 991			lp->cur_tx = -1;
 992			lp->timed_out = 0;
 993			didsomething++;
 994
 995			/* send another packet if there is one */
 996			go_tx(dev);
 997
 998			/* continue a split packet, if any */
 999			if (lp->outgoing.proto &&
1000			    lp->outgoing.proto->continue_tx) {
1001				int txbuf = get_arcbuf(dev);
1002
1003				if (txbuf != -1) {
1004					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
1005						/* that was the last segment */
1006						dev->stats.tx_bytes += lp->outgoing.skb->len;
1007						if (!lp->outgoing.proto->ack_tx) {
1008							dev_kfree_skb_irq(lp->outgoing.skb);
1009							lp->outgoing.proto = NULL;
1010						}
1011					}
1012					lp->next_tx = txbuf;
1013				}
1014			}
1015			/* inform upper layers of idleness, if necessary */
1016			if (lp->cur_tx == -1)
1017				netif_wake_queue(dev);
1018		}
1019		/* now process the received packet, if any */
1020		if (recbuf != -1) {
1021			if (BUGLVL(D_RX))
1022				arcnet_dump_packet(dev, recbuf, "rx irq", 0);
1023
1024			arcnet_rx(dev, recbuf);
1025			release_arcbuf(dev, recbuf);
1026
1027			didsomething++;
1028		}
1029		if (status & lp->intmask & RECONflag) {
1030			lp->hw.command(dev, CFLAGScmd | CONFIGclear);
1031			dev->stats.tx_carrier_errors++;
1032
1033			arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
1034				   status);
1035			if (netif_carrier_ok(dev)) {
1036				netif_carrier_off(dev);
1037				netdev_info(dev, "link down\n");
1038			}
1039			mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
1040
1041			arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
1042			/* MYRECON bit is at bit 7 of diagstatus */
1043			if (diagstatus & 0x80)
1044				arc_printk(D_RECON, dev, "Put out that recon myself\n");
1045
1046			/* is the RECON info empty or old? */
1047			if (!lp->first_recon || !lp->last_recon ||
1048			    time_after(jiffies, lp->last_recon + HZ * 10)) {
1049				if (lp->network_down)
1050					arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1051				lp->first_recon = lp->last_recon = jiffies;
1052				lp->num_recons = lp->network_down = 0;
1053
1054				arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1055			} else {	/* add to current RECON counter */
1056				lp->last_recon = jiffies;
1057				lp->num_recons++;
1058
1059				arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1060					   lp->num_recons,
1061					   (lp->last_recon - lp->first_recon) / HZ,
1062					   lp->network_down);
1063
1064				/* if network is marked up;
1065				 * and first_recon and last_recon are 60+ apart;
1066				 * and the average no. of recons counted is
1067				 *    > RECON_THRESHOLD/min;
1068				 * then print a warning message.
1069				 */
1070				if (!lp->network_down &&
1071				    (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1072				    lp->num_recons >= RECON_THRESHOLD) {
1073					lp->network_down = 1;
1074					arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1075				} else if (!lp->network_down &&
1076					   lp->last_recon - lp->first_recon > HZ * 60) {
1077					/* reset counters if we've gone for
1078					 *  over a minute.
1079					 */
1080					lp->first_recon = lp->last_recon;
1081					lp->num_recons = 1;
1082				}
1083			}
1084		} else if (lp->network_down &&
1085			   time_after(jiffies, lp->last_recon + HZ * 10)) {
1086			if (lp->network_down)
1087				arc_printk(D_NORMAL, dev, "cabling restored?\n");
1088			lp->first_recon = lp->last_recon = 0;
1089			lp->num_recons = lp->network_down = 0;
1090
1091			arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1092			netif_carrier_on(dev);
1093		}
1094
1095		if (didsomething)
1096			retval |= IRQ_HANDLED;
1097	} while (--boguscount && didsomething);
1098
1099	arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1100		   lp->hw.status(dev), boguscount);
1101	arc_printk(D_DURING, dev, "\n");
1102
1103	lp->hw.intmask(dev, 0);
1104	udelay(1);
1105	lp->hw.intmask(dev, lp->intmask);
1106
1107out:
1108	spin_unlock_irqrestore(&lp->lock, flags);
1109	return retval;
1110}
1111EXPORT_SYMBOL(arcnet_interrupt);
1112
1113/* This is a generic packet receiver that calls arcnet??_rx depending on the
1114 * protocol ID found.
1115 */
1116static void arcnet_rx(struct net_device *dev, int bufnum)
1117{
1118	struct arcnet_local *lp = netdev_priv(dev);
1119	union {
1120		struct archdr pkt;
1121		char buf[512];
1122	} rxdata;
1123	struct arc_rfc1201 *soft;
1124	int length, ofs;
1125
1126	soft = &rxdata.pkt.soft.rfc1201;
1127
1128	lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1129	if (rxdata.pkt.hard.offset[0]) {
1130		ofs = rxdata.pkt.hard.offset[0];
1131		length = 256 - ofs;
1132	} else {
1133		ofs = rxdata.pkt.hard.offset[1];
1134		length = 512 - ofs;
1135	}
1136
1137	/* get the full header, if possible */
1138	if (sizeof(rxdata.pkt.soft) <= length) {
1139		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1140	} else {
1141		memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1142		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1143	}
1144
1145	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1146		   bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1147
1148	dev->stats.rx_packets++;
1149	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1150
1151	/* call the right receiver for the protocol */
1152	if (arc_proto_map[soft->proto]->is_ip) {
1153		if (BUGLVL(D_PROTO)) {
1154			struct ArcProto
1155			*oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1156			*newp = arc_proto_map[soft->proto];
1157
1158			if (oldp != newp) {
1159				arc_printk(D_PROTO, dev,
1160					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1161					   soft->proto, rxdata.pkt.hard.source,
1162					   newp->suffix, oldp->suffix);
1163			}
1164		}
1165
1166		/* broadcasts will always be done with the last-used encap. */
1167		lp->default_proto[0] = soft->proto;
1168
1169		/* in striking contrast, the following isn't a hack. */
1170		lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1171	}
1172	/* call the protocol-specific receiver. */
1173	arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1174}
1175
1176static void null_rx(struct net_device *dev, int bufnum,
1177		    struct archdr *pkthdr, int length)
1178{
1179	arc_printk(D_PROTO, dev,
1180		   "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1181		   pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1182}
1183
1184static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1185			     unsigned short type, uint8_t daddr)
1186{
1187	struct arcnet_local *lp = netdev_priv(dev);
1188
1189	arc_printk(D_PROTO, dev,
1190		   "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1191		   lp->default_proto[daddr]);
1192
1193	/* always fails */
1194	return 0;
1195}
1196
1197/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1198static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1199			   int length, int bufnum)
1200{
1201	struct arcnet_local *lp = netdev_priv(dev);
1202	struct arc_hardware newpkt;
1203
1204	arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1205
1206	/* send a packet to myself -- will never get received, of course */
1207	newpkt.source = newpkt.dest = dev->dev_addr[0];
1208
1209	/* only one byte of actual data (and it's random) */
1210	newpkt.offset[0] = 0xFF;
1211
1212	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1213
1214	return 1;		/* done */
1215}
v5.4
   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 */
  62static void null_rx(struct net_device *dev, int bufnum,
  63		    struct archdr *pkthdr, int length);
  64static int null_build_header(struct sk_buff *skb, struct net_device *dev,
  65			     unsigned short type, uint8_t daddr);
  66static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
  67			   int length, int bufnum);
  68
  69static 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 */
  76struct ArcProto *arc_proto_map[256];
  77EXPORT_SYMBOL(arc_proto_map);
  78
  79struct ArcProto *arc_proto_default;
  80EXPORT_SYMBOL(arc_proto_default);
  81
  82struct ArcProto *arc_bcast_proto;
  83EXPORT_SYMBOL(arc_bcast_proto);
  84
  85struct ArcProto *arc_raw_proto;
  86EXPORT_SYMBOL(arc_raw_proto);
  87
  88static 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 */
 100int arcnet_debug = ARCNET_DEBUG;
 101EXPORT_SYMBOL(arcnet_debug);
 102
 103/* Internal function prototypes */
 104static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 105			 unsigned short type, const void *daddr,
 106			 const void *saddr, unsigned len);
 107static int go_tx(struct net_device *dev);
 108
 109static int debug = ARCNET_DEBUG;
 110module_param(debug, int, 0);
 111MODULE_LICENSE("GPL");
 112
 113static 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
 137static void __exit arcnet_exit(void)
 138{
 139}
 140
 141module_init(arcnet_init);
 142module_exit(arcnet_exit);
 143
 144/* Dump the contents of an sk_buff */
 145#if ARCNET_DEBUG_MAX & D_SKB
 146void 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}
 156EXPORT_SYMBOL(arcnet_dump_skb);
 157#endif
 158
 159/* Dump the contents of an ARCnet buffer */
 160#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 161static 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 */
 196void 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}
 221EXPORT_SYMBOL_GPL(arcnet_led_event);
 222
 223static 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 */
 235void 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}
 258EXPORT_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 */
 264void 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}
 280EXPORT_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 */
 288static 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 */
 308static 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
 341static 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
 356static const struct header_ops arcnet_header_ops = {
 357	.create = arcnet_header,
 358};
 359
 360static 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. */
 368static 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
 385static 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
 396static 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		kfree_skb(ackskb);
 438
 439	local_irq_enable();
 440};
 441
 442struct 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}
 459EXPORT_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 */
 468int 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}
 567EXPORT_SYMBOL(arcnet_open);
 568
 569/* The inverse routine to arcnet_open - shuts down the card. */
 570int 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}
 593EXPORT_SYMBOL(arcnet_close);
 594
 595static 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. */
 648netdev_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}
 732EXPORT_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 */
 737static 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 */
 766void 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}
 800EXPORT_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 */
 806irqreturn_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}
1058EXPORT_SYMBOL(arcnet_interrupt);
1059
1060/* This is a generic packet receiver that calls arcnet??_rx depending on the
1061 * protocol ID found.
1062 */
1063static 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
1123static 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
1131static 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. */
1145static 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}