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v6.13.7
   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#include <linux/workqueue.h>
  58
  59#include "arcdevice.h"
  60#include "com9026.h"
  61
  62/* "do nothing" functions for protocol drivers */
  63static void null_rx(struct net_device *dev, int bufnum,
  64		    struct archdr *pkthdr, int length);
  65static int null_build_header(struct sk_buff *skb, struct net_device *dev,
  66			     unsigned short type, uint8_t daddr);
  67static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
  68			   int length, int bufnum);
  69
  70static void arcnet_rx(struct net_device *dev, int bufnum);
  71
  72/* one ArcProto per possible proto ID.  None of the elements of
  73 * arc_proto_map are allowed to be NULL; they will get set to
  74 * arc_proto_default instead.  It also must not be NULL; if you would like
  75 * to set it to NULL, set it to &arc_proto_null instead.
  76 */
  77struct ArcProto *arc_proto_map[256];
  78EXPORT_SYMBOL(arc_proto_map);
  79
  80struct ArcProto *arc_proto_default;
  81EXPORT_SYMBOL(arc_proto_default);
  82
  83struct ArcProto *arc_bcast_proto;
  84EXPORT_SYMBOL(arc_bcast_proto);
  85
  86struct ArcProto *arc_raw_proto;
  87EXPORT_SYMBOL(arc_raw_proto);
  88
  89static struct ArcProto arc_proto_null = {
  90	.suffix		= '?',
  91	.mtu		= XMTU,
  92	.is_ip          = 0,
  93	.rx		= null_rx,
  94	.build_header	= null_build_header,
  95	.prepare_tx	= null_prepare_tx,
  96	.continue_tx    = NULL,
  97	.ack_tx         = NULL
  98};
  99
 100/* Exported function prototypes */
 101int arcnet_debug = ARCNET_DEBUG;
 102EXPORT_SYMBOL(arcnet_debug);
 103
 104/* Internal function prototypes */
 105static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 106			 unsigned short type, const void *daddr,
 107			 const void *saddr, unsigned len);
 108static int go_tx(struct net_device *dev);
 109
 110static int debug = ARCNET_DEBUG;
 111module_param(debug, int, 0);
 112MODULE_DESCRIPTION("ARCnet core driver");
 113MODULE_LICENSE("GPL");
 114
 115static int __init arcnet_init(void)
 116{
 117	int count;
 118
 119	arcnet_debug = debug;
 120
 121	pr_info("arcnet loaded\n");
 122
 123	/* initialize the protocol map */
 124	arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
 125	for (count = 0; count < 256; count++)
 126		arc_proto_map[count] = arc_proto_default;
 127
 128	if (BUGLVL(D_DURING))
 129		pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
 130			sizeof(struct arc_hardware),
 131			sizeof(struct arc_rfc1201),
 132			sizeof(struct arc_rfc1051),
 133			sizeof(struct arc_eth_encap),
 134			sizeof(struct archdr));
 135
 136	return 0;
 137}
 138
 139static void __exit arcnet_exit(void)
 140{
 141}
 142
 143module_init(arcnet_init);
 144module_exit(arcnet_exit);
 145
 146/* Dump the contents of an sk_buff */
 147#if ARCNET_DEBUG_MAX & D_SKB
 148void arcnet_dump_skb(struct net_device *dev,
 149		     struct sk_buff *skb, char *desc)
 150{
 151	char hdr[32];
 152
 153	/* dump the packet */
 154	snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
 155	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 156		       16, 1, skb->data, skb->len, true);
 157}
 158EXPORT_SYMBOL(arcnet_dump_skb);
 159#endif
 160
 161/* Dump the contents of an ARCnet buffer */
 162#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 163static void arcnet_dump_packet(struct net_device *dev, int bufnum,
 164			       char *desc, int take_arcnet_lock)
 165{
 166	struct arcnet_local *lp = netdev_priv(dev);
 167	int i, length;
 168	unsigned long flags = 0;
 169	static uint8_t buf[512];
 170	char hdr[32];
 171
 172	/* hw.copy_from_card expects IRQ context so take the IRQ lock
 173	 * to keep it single threaded
 174	 */
 175	if (take_arcnet_lock)
 176		spin_lock_irqsave(&lp->lock, flags);
 177
 178	lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
 179	if (take_arcnet_lock)
 180		spin_unlock_irqrestore(&lp->lock, flags);
 181
 182	/* if the offset[0] byte is nonzero, this is a 256-byte packet */
 183	length = (buf[2] ? 256 : 512);
 184
 185	/* dump the packet */
 186	snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
 187	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 188		       16, 1, buf, length, true);
 189}
 190
 191#else
 192
 193#define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
 194
 195#endif
 196
 197/* Trigger a LED event in response to a ARCNET device event */
 198void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
 199{
 200	struct arcnet_local *lp = netdev_priv(dev);
 201
 202	switch (event) {
 203	case ARCNET_LED_EVENT_RECON:
 204		led_trigger_blink_oneshot(lp->recon_led_trig, 350, 350, 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, 50, 50, 0);
 216		break;
 217	}
 218}
 219EXPORT_SYMBOL_GPL(arcnet_led_event);
 220
 221static void arcnet_led_release(struct device *gendev, void *res)
 222{
 223	struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
 224
 225	led_trigger_unregister_simple(lp->tx_led_trig);
 226	led_trigger_unregister_simple(lp->recon_led_trig);
 227}
 228
 229/* Register ARCNET LED triggers for a arcnet device
 230 *
 231 * This is normally called from a driver's probe function
 232 */
 233void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
 234{
 235	struct arcnet_local *lp = netdev_priv(netdev);
 236	void *res;
 237
 238	res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
 239	if (!res) {
 240		netdev_err(netdev, "cannot register LED triggers\n");
 241		return;
 242	}
 243
 244	snprintf(lp->tx_led_trig_name, sizeof(lp->tx_led_trig_name),
 245		 "arc%d-%d-tx", index, subid);
 246	snprintf(lp->recon_led_trig_name, sizeof(lp->recon_led_trig_name),
 247		 "arc%d-%d-recon", index, subid);
 248
 249	led_trigger_register_simple(lp->tx_led_trig_name,
 250				    &lp->tx_led_trig);
 251	led_trigger_register_simple(lp->recon_led_trig_name,
 252				    &lp->recon_led_trig);
 253
 254	devres_add(&netdev->dev, res);
 255}
 256EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
 257
 258/* Unregister a protocol driver from the arc_proto_map.  Protocol drivers
 259 * are responsible for registering themselves, but the unregister routine
 260 * is pretty generic so we'll do it here.
 261 */
 262void arcnet_unregister_proto(struct ArcProto *proto)
 263{
 264	int count;
 265
 266	if (arc_proto_default == proto)
 267		arc_proto_default = &arc_proto_null;
 268	if (arc_bcast_proto == proto)
 269		arc_bcast_proto = arc_proto_default;
 270	if (arc_raw_proto == proto)
 271		arc_raw_proto = arc_proto_default;
 272
 273	for (count = 0; count < 256; count++) {
 274		if (arc_proto_map[count] == proto)
 275			arc_proto_map[count] = arc_proto_default;
 276	}
 277}
 278EXPORT_SYMBOL(arcnet_unregister_proto);
 279
 280/* Add a buffer to the queue.  Only the interrupt handler is allowed to do
 281 * this, unless interrupts are disabled.
 282 *
 283 * Note: we don't check for a full queue, since there aren't enough buffers
 284 * to more than fill it.
 285 */
 286static void release_arcbuf(struct net_device *dev, int bufnum)
 287{
 288	struct arcnet_local *lp = netdev_priv(dev);
 289	int i;
 290
 291	lp->buf_queue[lp->first_free_buf++] = bufnum;
 292	lp->first_free_buf %= 5;
 293
 294	if (BUGLVL(D_DURING)) {
 295		arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
 296			   bufnum);
 297		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 298			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 299		arc_cont(D_DURING, "\n");
 300	}
 301}
 302
 303/* Get a buffer from the queue.
 304 * If this returns -1, there are no buffers available.
 305 */
 306static int get_arcbuf(struct net_device *dev)
 307{
 308	struct arcnet_local *lp = netdev_priv(dev);
 309	int buf = -1, i;
 310
 311	if (!atomic_dec_and_test(&lp->buf_lock)) {
 312		/* already in this function */
 313		arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
 314			   lp->buf_lock.counter);
 315	} else {			/* we can continue */
 316		if (lp->next_buf >= 5)
 317			lp->next_buf -= 5;
 318
 319		if (lp->next_buf == lp->first_free_buf) {
 320			arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
 321		} else {
 322			buf = lp->buf_queue[lp->next_buf++];
 323			lp->next_buf %= 5;
 324		}
 325	}
 326
 327	if (BUGLVL(D_DURING)) {
 328		arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
 329			   buf);
 330		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 331			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 332		arc_cont(D_DURING, "\n");
 333	}
 334
 335	atomic_inc(&lp->buf_lock);
 336	return buf;
 337}
 338
 339static int choose_mtu(void)
 340{
 341	int count, mtu = 65535;
 342
 343	/* choose the smallest MTU of all available encaps */
 344	for (count = 0; count < 256; count++) {
 345		if (arc_proto_map[count] != &arc_proto_null &&
 346		    arc_proto_map[count]->mtu < mtu) {
 347			mtu = arc_proto_map[count]->mtu;
 348		}
 349	}
 350
 351	return mtu == 65535 ? XMTU : mtu;
 352}
 353
 354static const struct header_ops arcnet_header_ops = {
 355	.create = arcnet_header,
 356};
 357
 358static const struct net_device_ops arcnet_netdev_ops = {
 359	.ndo_open	= arcnet_open,
 360	.ndo_stop	= arcnet_close,
 361	.ndo_start_xmit = arcnet_send_packet,
 362	.ndo_tx_timeout = arcnet_timeout,
 363};
 364
 365/* Setup a struct device for ARCnet. */
 366static void arcdev_setup(struct net_device *dev)
 367{
 368	dev->type = ARPHRD_ARCNET;
 369	dev->netdev_ops = &arcnet_netdev_ops;
 370	dev->header_ops = &arcnet_header_ops;
 371	dev->hard_header_len = sizeof(struct arc_hardware);
 372	dev->mtu = choose_mtu();
 373
 374	dev->addr_len = ARCNET_ALEN;
 375	dev->tx_queue_len = 100;
 376	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
 377	dev->watchdog_timeo = TX_TIMEOUT;
 378
 379	/* New-style flags. */
 380	dev->flags = IFF_BROADCAST;
 381}
 382
 383static void arcnet_timer(struct timer_list *t)
 384{
 385	struct arcnet_local *lp = from_timer(lp, t, timer);
 386	struct net_device *dev = lp->dev;
 387
 388	spin_lock_irq(&lp->lock);
 389
 390	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
 391		netif_carrier_on(dev);
 392		netdev_info(dev, "link up\n");
 393	}
 394
 395	spin_unlock_irq(&lp->lock);
 396}
 397
 398static void reset_device_work(struct work_struct *work)
 399{
 400	struct arcnet_local *lp;
 401	struct net_device *dev;
 402
 403	lp = container_of(work, struct arcnet_local, reset_work);
 404	dev = lp->dev;
 405
 406	/* Do not bring the network interface back up if an ifdown
 407	 * was already done.
 408	 */
 409	if (!netif_running(dev) || !lp->reset_in_progress)
 410		return;
 411
 412	rtnl_lock();
 413
 414	/* Do another check, in case of an ifdown that was triggered in
 415	 * the small race window between the exit condition above and
 416	 * acquiring RTNL.
 417	 */
 418	if (!netif_running(dev) || !lp->reset_in_progress)
 419		goto out;
 420
 421	dev_close(dev);
 422	dev_open(dev, NULL);
 423
 424out:
 425	rtnl_unlock();
 426}
 427
 428static void arcnet_reply_work(struct work_struct *t)
 429{
 430	struct arcnet_local *lp = from_work(lp, t, reply_work);
 431
 432	struct sk_buff *ackskb, *skb;
 433	struct sock_exterr_skb *serr;
 434	struct sock *sk;
 435	int ret;
 436
 437	local_irq_disable();
 438	skb = lp->outgoing.skb;
 439	if (!skb || !skb->sk) {
 440		local_irq_enable();
 441		return;
 442	}
 443
 444	sock_hold(skb->sk);
 445	sk = skb->sk;
 446	ackskb = skb_clone_sk(skb);
 447	sock_put(skb->sk);
 448
 449	if (!ackskb) {
 450		local_irq_enable();
 451		return;
 452	}
 453
 454	serr = SKB_EXT_ERR(ackskb);
 455	memset(serr, 0, sizeof(*serr));
 456	serr->ee.ee_errno = ENOMSG;
 457	serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
 458	serr->ee.ee_data = skb_shinfo(skb)->tskey;
 459	serr->ee.ee_info = lp->reply_status;
 460
 461	/* finally erasing outgoing skb */
 462	dev_kfree_skb(lp->outgoing.skb);
 463	lp->outgoing.skb = NULL;
 464
 465	ackskb->dev = lp->dev;
 466
 467	ret = sock_queue_err_skb(sk, ackskb);
 468	if (ret)
 469		dev_kfree_skb_irq(ackskb);
 470
 471	local_irq_enable();
 472};
 473
 474struct net_device *alloc_arcdev(const char *name)
 475{
 476	struct net_device *dev;
 477
 478	dev = alloc_netdev(sizeof(struct arcnet_local),
 479			   name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
 480			   arcdev_setup);
 481	if (dev) {
 482		struct arcnet_local *lp = netdev_priv(dev);
 483
 484		lp->dev = dev;
 485		spin_lock_init(&lp->lock);
 486		timer_setup(&lp->timer, arcnet_timer, 0);
 487		INIT_WORK(&lp->reset_work, reset_device_work);
 488	}
 489
 490	return dev;
 491}
 492EXPORT_SYMBOL(alloc_arcdev);
 493
 494void free_arcdev(struct net_device *dev)
 495{
 496	struct arcnet_local *lp = netdev_priv(dev);
 497
 498	/* Do not cancel this at ->ndo_close(), as the workqueue itself
 499	 * indirectly calls the ifdown path through dev_close().
 500	 */
 501	cancel_work_sync(&lp->reset_work);
 502	free_netdev(dev);
 503}
 504EXPORT_SYMBOL(free_arcdev);
 505
 506/* Open/initialize the board.  This is called sometime after booting when
 507 * the 'ifconfig' program is run.
 508 *
 509 * This routine should set everything up anew at each open, even registers
 510 * that "should" only need to be set once at boot, so that there is
 511 * non-reboot way to recover if something goes wrong.
 512 */
 513int arcnet_open(struct net_device *dev)
 514{
 515	struct arcnet_local *lp = netdev_priv(dev);
 516	int count, newmtu, error;
 517
 518	arc_printk(D_INIT, dev, "opened.");
 519
 520	if (!try_module_get(lp->hw.owner))
 521		return -ENODEV;
 522
 523	if (BUGLVL(D_PROTO)) {
 524		arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
 525			   arc_proto_default->suffix);
 526		for (count = 0; count < 256; count++)
 527			arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
 528		arc_cont(D_PROTO, "\n");
 529	}
 530
 531	INIT_WORK(&lp->reply_work, arcnet_reply_work);
 532
 533	arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 534
 535	/* try to put the card in a defined state - if it fails the first
 536	 * time, actually reset it.
 537	 */
 538	error = -ENODEV;
 539	if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
 540		goto out_module_put;
 541
 542	newmtu = choose_mtu();
 543	if (newmtu < dev->mtu)
 544		dev->mtu = newmtu;
 545
 546	arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
 547
 548	/* autodetect the encapsulation for each host. */
 549	memset(lp->default_proto, 0, sizeof(lp->default_proto));
 550
 551	/* the broadcast address is special - use the 'bcast' protocol */
 552	for (count = 0; count < 256; count++) {
 553		if (arc_proto_map[count] == arc_bcast_proto) {
 554			lp->default_proto[0] = count;
 555			break;
 556		}
 557	}
 558
 559	/* initialize buffers */
 560	atomic_set(&lp->buf_lock, 1);
 561
 562	lp->next_buf = lp->first_free_buf = 0;
 563	release_arcbuf(dev, 0);
 564	release_arcbuf(dev, 1);
 565	release_arcbuf(dev, 2);
 566	release_arcbuf(dev, 3);
 567	lp->cur_tx = lp->next_tx = -1;
 568	lp->cur_rx = -1;
 569
 570	lp->rfc1201.sequence = 1;
 571
 572	/* bring up the hardware driver */
 573	if (lp->hw.open)
 574		lp->hw.open(dev);
 575
 576	if (dev->dev_addr[0] == 0)
 577		arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
 578	else if (dev->dev_addr[0] == 255)
 579		arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
 580
 581	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 582	if (lp->hw.status(dev) & RESETflag) {
 583		arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
 584			   __FILE__, __LINE__, __func__);
 585		lp->hw.command(dev, CFLAGScmd | RESETclear);
 586	}
 587
 588	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 589	/* make sure we're ready to receive IRQ's. */
 590	lp->hw.intmask(dev, 0);
 591	udelay(1);		/* give it time to set the mask before
 592				 * we reset it again. (may not even be
 593				 * necessary)
 594				 */
 595	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 596	lp->intmask = NORXflag | RECONflag;
 597	lp->hw.intmask(dev, lp->intmask);
 598	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 599
 600	netif_carrier_off(dev);
 601	netif_start_queue(dev);
 602	mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 603
 604	arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
 605	return 0;
 606
 607 out_module_put:
 608	module_put(lp->hw.owner);
 609	return error;
 610}
 611EXPORT_SYMBOL(arcnet_open);
 612
 613/* The inverse routine to arcnet_open - shuts down the card. */
 614int arcnet_close(struct net_device *dev)
 615{
 616	struct arcnet_local *lp = netdev_priv(dev);
 617
 618	arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
 619	del_timer_sync(&lp->timer);
 620
 621	netif_stop_queue(dev);
 622	netif_carrier_off(dev);
 623
 624	cancel_work_sync(&lp->reply_work);
 625
 626	/* flush TX and disable RX */
 627	lp->hw.intmask(dev, 0);
 628	lp->hw.command(dev, NOTXcmd);	/* stop transmit */
 629	lp->hw.command(dev, NORXcmd);	/* disable receive */
 630	mdelay(1);
 631
 632	/* shut down the card */
 633	lp->hw.close(dev);
 634
 635	/* reset counters */
 636	lp->reset_in_progress = 0;
 637
 638	module_put(lp->hw.owner);
 639	return 0;
 640}
 641EXPORT_SYMBOL(arcnet_close);
 642
 643static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 644			 unsigned short type, const void *daddr,
 645			 const void *saddr, unsigned len)
 646{
 647	const struct arcnet_local *lp = netdev_priv(dev);
 648	uint8_t _daddr, proto_num;
 649	struct ArcProto *proto;
 650
 651	arc_printk(D_DURING, dev,
 652		   "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 653		   saddr ? *(uint8_t *)saddr : -1,
 654		   daddr ? *(uint8_t *)daddr : -1,
 655		   type, type, len);
 656
 657	if (skb->len != 0 && len != skb->len)
 658		arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 659			   skb->len, len);
 660
 661	/* Type is host order - ? */
 662	if (type == ETH_P_ARCNET) {
 663		proto = arc_raw_proto;
 664		arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
 665			   proto->suffix);
 666		_daddr = daddr ? *(uint8_t *)daddr : 0;
 667	} else if (!daddr) {
 668		/* if the dest addr isn't provided, we can't choose an
 669		 * encapsulation!  Store the packet type (eg. ETH_P_IP)
 670		 * for now, and we'll push on a real header when we do
 671		 * rebuild_header.
 672		 */
 673		*(uint16_t *)skb_push(skb, 2) = type;
 674		/* XXX: Why not use skb->mac_len? */
 675		if (skb->network_header - skb->mac_header != 2)
 676			arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
 677				   skb->network_header - skb->mac_header);
 678		return -2;	/* return error -- can't transmit yet! */
 679	} else {
 680		/* otherwise, we can just add the header as usual. */
 681		_daddr = *(uint8_t *)daddr;
 682		proto_num = lp->default_proto[_daddr];
 683		proto = arc_proto_map[proto_num];
 684		arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
 685			   proto_num, proto->suffix);
 686		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 687			arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
 688				   arc_bcast_proto->suffix);
 689			proto = arc_bcast_proto;
 690		}
 691	}
 692	return proto->build_header(skb, dev, type, _daddr);
 693}
 694
 695/* Called by the kernel in order to transmit a packet. */
 696netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 697			       struct net_device *dev)
 698{
 699	struct arcnet_local *lp = netdev_priv(dev);
 700	struct archdr *pkt;
 701	struct arc_rfc1201 *soft;
 702	struct ArcProto *proto;
 703	int txbuf;
 704	unsigned long flags;
 705	int retval;
 706
 707	arc_printk(D_DURING, dev,
 708		   "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 709		   lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
 710
 711	pkt = (struct archdr *)skb->data;
 712	soft = &pkt->soft.rfc1201;
 713	proto = arc_proto_map[soft->proto];
 714
 715	arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
 716		   skb->len, pkt->hard.dest);
 717	if (BUGLVL(D_SKB))
 718		arcnet_dump_skb(dev, skb, "tx");
 719
 720	/* fits in one packet? */
 721	if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 722		arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
 723		dev_kfree_skb(skb);
 724		return NETDEV_TX_OK;	/* don't try again */
 725	}
 726
 727	/* We're busy transmitting a packet... */
 728	netif_stop_queue(dev);
 729
 730	spin_lock_irqsave(&lp->lock, flags);
 731	lp->hw.intmask(dev, 0);
 732	if (lp->next_tx == -1)
 733		txbuf = get_arcbuf(dev);
 734	else
 735		txbuf = -1;
 736
 737	if (txbuf != -1) {
 738		lp->outgoing.skb = skb;
 739		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 740		    !proto->ack_tx) {
 741			/* done right away and we don't want to acknowledge
 742			 *  the package later - forget about it now
 743			 */
 744			dev->stats.tx_bytes += skb->len;
 745		} else {
 746			/* do it the 'split' way */
 747			lp->outgoing.proto = proto;
 748			lp->outgoing.skb = skb;
 749			lp->outgoing.pkt = pkt;
 750
 751			if (proto->continue_tx &&
 752			    proto->continue_tx(dev, txbuf)) {
 753				arc_printk(D_NORMAL, dev,
 754					   "bug! continue_tx finished the first time! (proto='%c')\n",
 755					   proto->suffix);
 756			}
 757		}
 758		retval = NETDEV_TX_OK;
 759		lp->next_tx = txbuf;
 760	} else {
 761		retval = NETDEV_TX_BUSY;
 762	}
 763
 764	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 765		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 766	/* make sure we didn't ignore a TX IRQ while we were in here */
 767	lp->hw.intmask(dev, 0);
 768
 769	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 770	lp->intmask |= TXFREEflag | EXCNAKflag;
 771	lp->hw.intmask(dev, lp->intmask);
 772	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 773		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 774
 775	arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
 776
 777	spin_unlock_irqrestore(&lp->lock, flags);
 778	return retval;		/* no need to try again */
 779}
 780EXPORT_SYMBOL(arcnet_send_packet);
 781
 782/* Actually start transmitting a packet that was loaded into a buffer
 783 * by prepare_tx.  This should _only_ be called by the interrupt handler.
 784 */
 785static int go_tx(struct net_device *dev)
 786{
 787	struct arcnet_local *lp = netdev_priv(dev);
 788
 789	arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 790		   lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
 791
 792	if (lp->cur_tx != -1 || lp->next_tx == -1)
 793		return 0;
 794
 795	if (BUGLVL(D_TX))
 796		arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 797
 798	lp->cur_tx = lp->next_tx;
 799	lp->next_tx = -1;
 800
 801	/* start sending */
 802	lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
 803
 804	dev->stats.tx_packets++;
 805	lp->lasttrans_dest = lp->lastload_dest;
 806	lp->lastload_dest = 0;
 807	lp->excnak_pending = 0;
 808	lp->intmask |= TXFREEflag | EXCNAKflag;
 809
 810	return 1;
 811}
 812
 813/* Called by the kernel when transmit times out */
 814void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
 815{
 816	unsigned long flags;
 817	struct arcnet_local *lp = netdev_priv(dev);
 818	int status = lp->hw.status(dev);
 819	char *msg;
 820
 821	spin_lock_irqsave(&lp->lock, flags);
 822	if (status & TXFREEflag) {	/* transmit _DID_ finish */
 823		msg = " - missed IRQ?";
 824	} else {
 825		msg = "";
 826		dev->stats.tx_aborted_errors++;
 827		lp->timed_out = 1;
 828		lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
 829	}
 830	dev->stats.tx_errors++;
 831
 832	/* make sure we didn't miss a TX or a EXC NAK IRQ */
 833	lp->hw.intmask(dev, 0);
 834	lp->intmask |= TXFREEflag | EXCNAKflag;
 835	lp->hw.intmask(dev, lp->intmask);
 836
 837	spin_unlock_irqrestore(&lp->lock, flags);
 838
 839	if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
 840		arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 841			   msg, status, lp->intmask, lp->lasttrans_dest);
 842		lp->last_timeout = jiffies;
 843	}
 844
 845	if (lp->cur_tx == -1)
 846		netif_wake_queue(dev);
 847}
 848EXPORT_SYMBOL(arcnet_timeout);
 849
 850/* The typical workload of the driver: Handle the network interface
 851 * interrupts. Establish which device needs attention, and call the correct
 852 * chipset interrupt handler.
 853 */
 854irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 855{
 856	struct net_device *dev = dev_id;
 857	struct arcnet_local *lp;
 858	int recbuf, status, diagstatus, didsomething, boguscount;
 859	unsigned long flags;
 860	int retval = IRQ_NONE;
 861
 862	arc_printk(D_DURING, dev, "\n");
 863
 864	arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
 865
 866	lp = netdev_priv(dev);
 867	BUG_ON(!lp);
 868
 869	spin_lock_irqsave(&lp->lock, flags);
 870
 871	if (lp->reset_in_progress)
 872		goto out;
 873
 874	/* RESET flag was enabled - if device is not running, we must
 875	 * clear it right away (but nothing else).
 876	 */
 877	if (!netif_running(dev)) {
 878		if (lp->hw.status(dev) & RESETflag)
 879			lp->hw.command(dev, CFLAGScmd | RESETclear);
 880		lp->hw.intmask(dev, 0);
 881		spin_unlock_irqrestore(&lp->lock, flags);
 882		return retval;
 883	}
 884
 885	arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 886		   lp->hw.status(dev), lp->intmask);
 887
 888	boguscount = 5;
 889	do {
 890		status = lp->hw.status(dev);
 891		diagstatus = (status >> 8) & 0xFF;
 892
 893		arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
 894			   __FILE__, __LINE__, __func__, status);
 895		didsomething = 0;
 896
 897		/* RESET flag was enabled - card is resetting and if RX is
 898		 * disabled, it's NOT because we just got a packet.
 899		 *
 900		 * The card is in an undefined state.
 901		 * Clear it out and start over.
 902		 */
 903		if (status & RESETflag) {
 904			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 905				   status);
 906
 907			lp->reset_in_progress = 1;
 908			netif_stop_queue(dev);
 909			netif_carrier_off(dev);
 910			schedule_work(&lp->reset_work);
 911
 912			/* get out of the interrupt handler! */
 913			goto out;
 914		}
 915		/* RX is inhibited - we must have received something.
 916		 * Prepare to receive into the next buffer.
 917		 *
 918		 * We don't actually copy the received packet from the card
 919		 * until after the transmit handler runs (and possibly
 920		 * launches the next tx); this should improve latency slightly
 921		 * if we get both types of interrupts at once.
 922		 */
 923		recbuf = -1;
 924		if (status & lp->intmask & NORXflag) {
 925			recbuf = lp->cur_rx;
 926			arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
 927				   recbuf, status);
 928
 929			lp->cur_rx = get_arcbuf(dev);
 930			if (lp->cur_rx != -1) {
 931				arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
 932					   lp->cur_rx);
 933				lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
 934			}
 935			didsomething++;
 936		}
 937
 938		if ((diagstatus & EXCNAKflag)) {
 939			arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
 940				   diagstatus);
 941
 942			lp->hw.command(dev, NOTXcmd);      /* disable transmit */
 943			lp->excnak_pending = 1;
 944
 945			lp->hw.command(dev, EXCNAKclear);
 946			lp->intmask &= ~(EXCNAKflag);
 947			didsomething++;
 948		}
 949
 950		/* a transmit finished, and we're interested in it. */
 951		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 952			int ackstatus;
 953			lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 954
 955			if (status & TXACKflag)
 956				ackstatus = 2;
 957			else if (lp->excnak_pending)
 958				ackstatus = 1;
 959			else
 960				ackstatus = 0;
 961
 962			arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
 963				   status);
 964
 965			if (lp->cur_tx != -1 && !lp->timed_out) {
 966				if (!(status & TXACKflag)) {
 967					if (lp->lasttrans_dest != 0) {
 968						arc_printk(D_EXTRA, dev,
 969							   "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
 970							   status,
 971							   lp->lasttrans_dest);
 972						dev->stats.tx_errors++;
 973						dev->stats.tx_carrier_errors++;
 974					} else {
 975						arc_printk(D_DURING, dev,
 976							   "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
 977							   status,
 978							   lp->lasttrans_dest);
 979					}
 980				}
 981
 982				if (lp->outgoing.proto &&
 983				    lp->outgoing.proto->ack_tx) {
 984					lp->outgoing.proto
 985						->ack_tx(dev, ackstatus);
 986				}
 987				lp->reply_status = ackstatus;
 988				queue_work(system_bh_highpri_wq, &lp->reply_work);
 989			}
 990			if (lp->cur_tx != -1)
 991				release_arcbuf(dev, lp->cur_tx);
 992
 993			lp->cur_tx = -1;
 994			lp->timed_out = 0;
 995			didsomething++;
 996
 997			/* send another packet if there is one */
 998			go_tx(dev);
 999
1000			/* continue a split packet, if any */
1001			if (lp->outgoing.proto &&
1002			    lp->outgoing.proto->continue_tx) {
1003				int txbuf = get_arcbuf(dev);
1004
1005				if (txbuf != -1) {
1006					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
1007						/* that was the last segment */
1008						dev->stats.tx_bytes += lp->outgoing.skb->len;
1009						if (!lp->outgoing.proto->ack_tx) {
1010							dev_kfree_skb_irq(lp->outgoing.skb);
1011							lp->outgoing.proto = NULL;
1012						}
1013					}
1014					lp->next_tx = txbuf;
1015				}
1016			}
1017			/* inform upper layers of idleness, if necessary */
1018			if (lp->cur_tx == -1)
1019				netif_wake_queue(dev);
1020		}
1021		/* now process the received packet, if any */
1022		if (recbuf != -1) {
1023			if (BUGLVL(D_RX))
1024				arcnet_dump_packet(dev, recbuf, "rx irq", 0);
1025
1026			arcnet_rx(dev, recbuf);
1027			release_arcbuf(dev, recbuf);
1028
1029			didsomething++;
1030		}
1031		if (status & lp->intmask & RECONflag) {
1032			lp->hw.command(dev, CFLAGScmd | CONFIGclear);
1033			dev->stats.tx_carrier_errors++;
1034
1035			arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
1036				   status);
1037			if (netif_carrier_ok(dev)) {
1038				netif_carrier_off(dev);
1039				netdev_info(dev, "link down\n");
1040			}
1041			mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
1042
1043			arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
1044			/* MYRECON bit is at bit 7 of diagstatus */
1045			if (diagstatus & 0x80)
1046				arc_printk(D_RECON, dev, "Put out that recon myself\n");
1047
1048			/* is the RECON info empty or old? */
1049			if (!lp->first_recon || !lp->last_recon ||
1050			    time_after(jiffies, lp->last_recon + HZ * 10)) {
1051				if (lp->network_down)
1052					arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1053				lp->first_recon = lp->last_recon = jiffies;
1054				lp->num_recons = lp->network_down = 0;
1055
1056				arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1057			} else {	/* add to current RECON counter */
1058				lp->last_recon = jiffies;
1059				lp->num_recons++;
1060
1061				arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1062					   lp->num_recons,
1063					   (lp->last_recon - lp->first_recon) / HZ,
1064					   lp->network_down);
1065
1066				/* if network is marked up;
1067				 * and first_recon and last_recon are 60+ apart;
1068				 * and the average no. of recons counted is
1069				 *    > RECON_THRESHOLD/min;
1070				 * then print a warning message.
1071				 */
1072				if (!lp->network_down &&
1073				    (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1074				    lp->num_recons >= RECON_THRESHOLD) {
1075					lp->network_down = 1;
1076					arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1077				} else if (!lp->network_down &&
1078					   lp->last_recon - lp->first_recon > HZ * 60) {
1079					/* reset counters if we've gone for
1080					 *  over a minute.
1081					 */
1082					lp->first_recon = lp->last_recon;
1083					lp->num_recons = 1;
1084				}
1085			}
1086		} else if (lp->network_down &&
1087			   time_after(jiffies, lp->last_recon + HZ * 10)) {
1088			if (lp->network_down)
1089				arc_printk(D_NORMAL, dev, "cabling restored?\n");
1090			lp->first_recon = lp->last_recon = 0;
1091			lp->num_recons = lp->network_down = 0;
1092
1093			arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1094			netif_carrier_on(dev);
1095		}
1096
1097		if (didsomething)
1098			retval |= IRQ_HANDLED;
1099	} while (--boguscount && didsomething);
1100
1101	arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1102		   lp->hw.status(dev), boguscount);
1103	arc_printk(D_DURING, dev, "\n");
1104
1105	lp->hw.intmask(dev, 0);
1106	udelay(1);
1107	lp->hw.intmask(dev, lp->intmask);
1108
1109out:
1110	spin_unlock_irqrestore(&lp->lock, flags);
1111	return retval;
1112}
1113EXPORT_SYMBOL(arcnet_interrupt);
1114
1115/* This is a generic packet receiver that calls arcnet??_rx depending on the
1116 * protocol ID found.
1117 */
1118static void arcnet_rx(struct net_device *dev, int bufnum)
1119{
1120	struct arcnet_local *lp = netdev_priv(dev);
1121	union {
1122		struct archdr pkt;
1123		char buf[512];
1124	} rxdata;
1125	struct arc_rfc1201 *soft;
1126	int length, ofs;
1127
1128	soft = &rxdata.pkt.soft.rfc1201;
1129
1130	lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1131	if (rxdata.pkt.hard.offset[0]) {
1132		ofs = rxdata.pkt.hard.offset[0];
1133		length = 256 - ofs;
1134	} else {
1135		ofs = rxdata.pkt.hard.offset[1];
1136		length = 512 - ofs;
1137	}
1138
1139	/* get the full header, if possible */
1140	if (sizeof(rxdata.pkt.soft) <= length) {
1141		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1142	} else {
1143		memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1144		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1145	}
1146
1147	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1148		   bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1149
1150	dev->stats.rx_packets++;
1151	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1152
1153	/* call the right receiver for the protocol */
1154	if (arc_proto_map[soft->proto]->is_ip) {
1155		if (BUGLVL(D_PROTO)) {
1156			struct ArcProto
1157			*oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1158			*newp = arc_proto_map[soft->proto];
1159
1160			if (oldp != newp) {
1161				arc_printk(D_PROTO, dev,
1162					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1163					   soft->proto, rxdata.pkt.hard.source,
1164					   newp->suffix, oldp->suffix);
1165			}
1166		}
1167
1168		/* broadcasts will always be done with the last-used encap. */
1169		lp->default_proto[0] = soft->proto;
1170
1171		/* in striking contrast, the following isn't a hack. */
1172		lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1173	}
1174	/* call the protocol-specific receiver. */
1175	arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1176}
1177
1178static void null_rx(struct net_device *dev, int bufnum,
1179		    struct archdr *pkthdr, int length)
1180{
1181	arc_printk(D_PROTO, dev,
1182		   "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1183		   pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1184}
1185
1186static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1187			     unsigned short type, uint8_t daddr)
1188{
1189	struct arcnet_local *lp = netdev_priv(dev);
1190
1191	arc_printk(D_PROTO, dev,
1192		   "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1193		   lp->default_proto[daddr]);
1194
1195	/* always fails */
1196	return 0;
1197}
1198
1199/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1200static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1201			   int length, int bufnum)
1202{
1203	struct arcnet_local *lp = netdev_priv(dev);
1204	struct arc_hardware newpkt;
1205
1206	arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1207
1208	/* send a packet to myself -- will never get received, of course */
1209	newpkt.source = newpkt.dest = dev->dev_addr[0];
1210
1211	/* only one byte of actual data (and it's random) */
1212	newpkt.offset[0] = 0xFF;
1213
1214	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1215
1216	return 1;		/* done */
1217}
v6.9.4
   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_DESCRIPTION("ARCnet core driver");
 112MODULE_LICENSE("GPL");
 113
 114static int __init arcnet_init(void)
 115{
 116	int count;
 117
 118	arcnet_debug = debug;
 119
 120	pr_info("arcnet loaded\n");
 121
 122	/* initialize the protocol map */
 123	arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
 124	for (count = 0; count < 256; count++)
 125		arc_proto_map[count] = arc_proto_default;
 126
 127	if (BUGLVL(D_DURING))
 128		pr_info("struct sizes: %zd %zd %zd %zd %zd\n",
 129			sizeof(struct arc_hardware),
 130			sizeof(struct arc_rfc1201),
 131			sizeof(struct arc_rfc1051),
 132			sizeof(struct arc_eth_encap),
 133			sizeof(struct archdr));
 134
 135	return 0;
 136}
 137
 138static void __exit arcnet_exit(void)
 139{
 140}
 141
 142module_init(arcnet_init);
 143module_exit(arcnet_exit);
 144
 145/* Dump the contents of an sk_buff */
 146#if ARCNET_DEBUG_MAX & D_SKB
 147void arcnet_dump_skb(struct net_device *dev,
 148		     struct sk_buff *skb, char *desc)
 149{
 150	char hdr[32];
 151
 152	/* dump the packet */
 153	snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
 154	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 155		       16, 1, skb->data, skb->len, true);
 156}
 157EXPORT_SYMBOL(arcnet_dump_skb);
 158#endif
 159
 160/* Dump the contents of an ARCnet buffer */
 161#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 162static void arcnet_dump_packet(struct net_device *dev, int bufnum,
 163			       char *desc, int take_arcnet_lock)
 164{
 165	struct arcnet_local *lp = netdev_priv(dev);
 166	int i, length;
 167	unsigned long flags = 0;
 168	static uint8_t buf[512];
 169	char hdr[32];
 170
 171	/* hw.copy_from_card expects IRQ context so take the IRQ lock
 172	 * to keep it single threaded
 173	 */
 174	if (take_arcnet_lock)
 175		spin_lock_irqsave(&lp->lock, flags);
 176
 177	lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
 178	if (take_arcnet_lock)
 179		spin_unlock_irqrestore(&lp->lock, flags);
 180
 181	/* if the offset[0] byte is nonzero, this is a 256-byte packet */
 182	length = (buf[2] ? 256 : 512);
 183
 184	/* dump the packet */
 185	snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
 186	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 187		       16, 1, buf, length, true);
 188}
 189
 190#else
 191
 192#define arcnet_dump_packet(dev, bufnum, desc, take_arcnet_lock) do { } while (0)
 193
 194#endif
 195
 196/* Trigger a LED event in response to a ARCNET device event */
 197void arcnet_led_event(struct net_device *dev, enum arcnet_led_event event)
 198{
 199	struct arcnet_local *lp = netdev_priv(dev);
 200
 201	switch (event) {
 202	case ARCNET_LED_EVENT_RECON:
 203		led_trigger_blink_oneshot(lp->recon_led_trig, 350, 350, 0);
 204		break;
 205	case ARCNET_LED_EVENT_OPEN:
 206		led_trigger_event(lp->tx_led_trig, LED_OFF);
 207		led_trigger_event(lp->recon_led_trig, LED_OFF);
 208		break;
 209	case ARCNET_LED_EVENT_STOP:
 210		led_trigger_event(lp->tx_led_trig, LED_OFF);
 211		led_trigger_event(lp->recon_led_trig, LED_OFF);
 212		break;
 213	case ARCNET_LED_EVENT_TX:
 214		led_trigger_blink_oneshot(lp->tx_led_trig, 50, 50, 0);
 215		break;
 216	}
 217}
 218EXPORT_SYMBOL_GPL(arcnet_led_event);
 219
 220static void arcnet_led_release(struct device *gendev, void *res)
 221{
 222	struct arcnet_local *lp = netdev_priv(to_net_dev(gendev));
 223
 224	led_trigger_unregister_simple(lp->tx_led_trig);
 225	led_trigger_unregister_simple(lp->recon_led_trig);
 226}
 227
 228/* Register ARCNET LED triggers for a arcnet device
 229 *
 230 * This is normally called from a driver's probe function
 231 */
 232void devm_arcnet_led_init(struct net_device *netdev, int index, int subid)
 233{
 234	struct arcnet_local *lp = netdev_priv(netdev);
 235	void *res;
 236
 237	res = devres_alloc(arcnet_led_release, 0, GFP_KERNEL);
 238	if (!res) {
 239		netdev_err(netdev, "cannot register LED triggers\n");
 240		return;
 241	}
 242
 243	snprintf(lp->tx_led_trig_name, sizeof(lp->tx_led_trig_name),
 244		 "arc%d-%d-tx", index, subid);
 245	snprintf(lp->recon_led_trig_name, sizeof(lp->recon_led_trig_name),
 246		 "arc%d-%d-recon", index, subid);
 247
 248	led_trigger_register_simple(lp->tx_led_trig_name,
 249				    &lp->tx_led_trig);
 250	led_trigger_register_simple(lp->recon_led_trig_name,
 251				    &lp->recon_led_trig);
 252
 253	devres_add(&netdev->dev, res);
 254}
 255EXPORT_SYMBOL_GPL(devm_arcnet_led_init);
 256
 257/* Unregister a protocol driver from the arc_proto_map.  Protocol drivers
 258 * are responsible for registering themselves, but the unregister routine
 259 * is pretty generic so we'll do it here.
 260 */
 261void arcnet_unregister_proto(struct ArcProto *proto)
 262{
 263	int count;
 264
 265	if (arc_proto_default == proto)
 266		arc_proto_default = &arc_proto_null;
 267	if (arc_bcast_proto == proto)
 268		arc_bcast_proto = arc_proto_default;
 269	if (arc_raw_proto == proto)
 270		arc_raw_proto = arc_proto_default;
 271
 272	for (count = 0; count < 256; count++) {
 273		if (arc_proto_map[count] == proto)
 274			arc_proto_map[count] = arc_proto_default;
 275	}
 276}
 277EXPORT_SYMBOL(arcnet_unregister_proto);
 278
 279/* Add a buffer to the queue.  Only the interrupt handler is allowed to do
 280 * this, unless interrupts are disabled.
 281 *
 282 * Note: we don't check for a full queue, since there aren't enough buffers
 283 * to more than fill it.
 284 */
 285static void release_arcbuf(struct net_device *dev, int bufnum)
 286{
 287	struct arcnet_local *lp = netdev_priv(dev);
 288	int i;
 289
 290	lp->buf_queue[lp->first_free_buf++] = bufnum;
 291	lp->first_free_buf %= 5;
 292
 293	if (BUGLVL(D_DURING)) {
 294		arc_printk(D_DURING, dev, "release_arcbuf: freed #%d; buffer queue is now: ",
 295			   bufnum);
 296		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 297			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 298		arc_cont(D_DURING, "\n");
 299	}
 300}
 301
 302/* Get a buffer from the queue.
 303 * If this returns -1, there are no buffers available.
 304 */
 305static int get_arcbuf(struct net_device *dev)
 306{
 307	struct arcnet_local *lp = netdev_priv(dev);
 308	int buf = -1, i;
 309
 310	if (!atomic_dec_and_test(&lp->buf_lock)) {
 311		/* already in this function */
 312		arc_printk(D_NORMAL, dev, "get_arcbuf: overlap (%d)!\n",
 313			   lp->buf_lock.counter);
 314	} else {			/* we can continue */
 315		if (lp->next_buf >= 5)
 316			lp->next_buf -= 5;
 317
 318		if (lp->next_buf == lp->first_free_buf) {
 319			arc_printk(D_NORMAL, dev, "get_arcbuf: BUG: no buffers are available??\n");
 320		} else {
 321			buf = lp->buf_queue[lp->next_buf++];
 322			lp->next_buf %= 5;
 323		}
 324	}
 325
 326	if (BUGLVL(D_DURING)) {
 327		arc_printk(D_DURING, dev, "get_arcbuf: got #%d; buffer queue is now: ",
 328			   buf);
 329		for (i = lp->next_buf; i != lp->first_free_buf; i = (i + 1) % 5)
 330			arc_cont(D_DURING, "#%d ", lp->buf_queue[i]);
 331		arc_cont(D_DURING, "\n");
 332	}
 333
 334	atomic_inc(&lp->buf_lock);
 335	return buf;
 336}
 337
 338static int choose_mtu(void)
 339{
 340	int count, mtu = 65535;
 341
 342	/* choose the smallest MTU of all available encaps */
 343	for (count = 0; count < 256; count++) {
 344		if (arc_proto_map[count] != &arc_proto_null &&
 345		    arc_proto_map[count]->mtu < mtu) {
 346			mtu = arc_proto_map[count]->mtu;
 347		}
 348	}
 349
 350	return mtu == 65535 ? XMTU : mtu;
 351}
 352
 353static const struct header_ops arcnet_header_ops = {
 354	.create = arcnet_header,
 355};
 356
 357static const struct net_device_ops arcnet_netdev_ops = {
 358	.ndo_open	= arcnet_open,
 359	.ndo_stop	= arcnet_close,
 360	.ndo_start_xmit = arcnet_send_packet,
 361	.ndo_tx_timeout = arcnet_timeout,
 362};
 363
 364/* Setup a struct device for ARCnet. */
 365static void arcdev_setup(struct net_device *dev)
 366{
 367	dev->type = ARPHRD_ARCNET;
 368	dev->netdev_ops = &arcnet_netdev_ops;
 369	dev->header_ops = &arcnet_header_ops;
 370	dev->hard_header_len = sizeof(struct arc_hardware);
 371	dev->mtu = choose_mtu();
 372
 373	dev->addr_len = ARCNET_ALEN;
 374	dev->tx_queue_len = 100;
 375	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
 376	dev->watchdog_timeo = TX_TIMEOUT;
 377
 378	/* New-style flags. */
 379	dev->flags = IFF_BROADCAST;
 380}
 381
 382static void arcnet_timer(struct timer_list *t)
 383{
 384	struct arcnet_local *lp = from_timer(lp, t, timer);
 385	struct net_device *dev = lp->dev;
 386
 387	spin_lock_irq(&lp->lock);
 388
 389	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
 390		netif_carrier_on(dev);
 391		netdev_info(dev, "link up\n");
 392	}
 393
 394	spin_unlock_irq(&lp->lock);
 395}
 396
 397static void reset_device_work(struct work_struct *work)
 398{
 399	struct arcnet_local *lp;
 400	struct net_device *dev;
 401
 402	lp = container_of(work, struct arcnet_local, reset_work);
 403	dev = lp->dev;
 404
 405	/* Do not bring the network interface back up if an ifdown
 406	 * was already done.
 407	 */
 408	if (!netif_running(dev) || !lp->reset_in_progress)
 409		return;
 410
 411	rtnl_lock();
 412
 413	/* Do another check, in case of an ifdown that was triggered in
 414	 * the small race window between the exit condition above and
 415	 * acquiring RTNL.
 416	 */
 417	if (!netif_running(dev) || !lp->reset_in_progress)
 418		goto out;
 419
 420	dev_close(dev);
 421	dev_open(dev, NULL);
 422
 423out:
 424	rtnl_unlock();
 425}
 426
 427static void arcnet_reply_tasklet(struct tasklet_struct *t)
 428{
 429	struct arcnet_local *lp = from_tasklet(lp, t, reply_tasklet);
 430
 431	struct sk_buff *ackskb, *skb;
 432	struct sock_exterr_skb *serr;
 433	struct sock *sk;
 434	int ret;
 435
 436	local_irq_disable();
 437	skb = lp->outgoing.skb;
 438	if (!skb || !skb->sk) {
 439		local_irq_enable();
 440		return;
 441	}
 442
 443	sock_hold(skb->sk);
 444	sk = skb->sk;
 445	ackskb = skb_clone_sk(skb);
 446	sock_put(skb->sk);
 447
 448	if (!ackskb) {
 449		local_irq_enable();
 450		return;
 451	}
 452
 453	serr = SKB_EXT_ERR(ackskb);
 454	memset(serr, 0, sizeof(*serr));
 455	serr->ee.ee_errno = ENOMSG;
 456	serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS;
 457	serr->ee.ee_data = skb_shinfo(skb)->tskey;
 458	serr->ee.ee_info = lp->reply_status;
 459
 460	/* finally erasing outgoing skb */
 461	dev_kfree_skb(lp->outgoing.skb);
 462	lp->outgoing.skb = NULL;
 463
 464	ackskb->dev = lp->dev;
 465
 466	ret = sock_queue_err_skb(sk, ackskb);
 467	if (ret)
 468		dev_kfree_skb_irq(ackskb);
 469
 470	local_irq_enable();
 471};
 472
 473struct net_device *alloc_arcdev(const char *name)
 474{
 475	struct net_device *dev;
 476
 477	dev = alloc_netdev(sizeof(struct arcnet_local),
 478			   name && *name ? name : "arc%d", NET_NAME_UNKNOWN,
 479			   arcdev_setup);
 480	if (dev) {
 481		struct arcnet_local *lp = netdev_priv(dev);
 482
 483		lp->dev = dev;
 484		spin_lock_init(&lp->lock);
 485		timer_setup(&lp->timer, arcnet_timer, 0);
 486		INIT_WORK(&lp->reset_work, reset_device_work);
 487	}
 488
 489	return dev;
 490}
 491EXPORT_SYMBOL(alloc_arcdev);
 492
 493void free_arcdev(struct net_device *dev)
 494{
 495	struct arcnet_local *lp = netdev_priv(dev);
 496
 497	/* Do not cancel this at ->ndo_close(), as the workqueue itself
 498	 * indirectly calls the ifdown path through dev_close().
 499	 */
 500	cancel_work_sync(&lp->reset_work);
 501	free_netdev(dev);
 502}
 503EXPORT_SYMBOL(free_arcdev);
 504
 505/* Open/initialize the board.  This is called sometime after booting when
 506 * the 'ifconfig' program is run.
 507 *
 508 * This routine should set everything up anew at each open, even registers
 509 * that "should" only need to be set once at boot, so that there is
 510 * non-reboot way to recover if something goes wrong.
 511 */
 512int arcnet_open(struct net_device *dev)
 513{
 514	struct arcnet_local *lp = netdev_priv(dev);
 515	int count, newmtu, error;
 516
 517	arc_printk(D_INIT, dev, "opened.");
 518
 519	if (!try_module_get(lp->hw.owner))
 520		return -ENODEV;
 521
 522	if (BUGLVL(D_PROTO)) {
 523		arc_printk(D_PROTO, dev, "protocol map (default is '%c'): ",
 524			   arc_proto_default->suffix);
 525		for (count = 0; count < 256; count++)
 526			arc_cont(D_PROTO, "%c", arc_proto_map[count]->suffix);
 527		arc_cont(D_PROTO, "\n");
 528	}
 529
 530	tasklet_setup(&lp->reply_tasklet, arcnet_reply_tasklet);
 531
 532	arc_printk(D_INIT, dev, "arcnet_open: resetting card.\n");
 533
 534	/* try to put the card in a defined state - if it fails the first
 535	 * time, actually reset it.
 536	 */
 537	error = -ENODEV;
 538	if (lp->hw.reset(dev, 0) && lp->hw.reset(dev, 1))
 539		goto out_module_put;
 540
 541	newmtu = choose_mtu();
 542	if (newmtu < dev->mtu)
 543		dev->mtu = newmtu;
 544
 545	arc_printk(D_INIT, dev, "arcnet_open: mtu: %d.\n", dev->mtu);
 546
 547	/* autodetect the encapsulation for each host. */
 548	memset(lp->default_proto, 0, sizeof(lp->default_proto));
 549
 550	/* the broadcast address is special - use the 'bcast' protocol */
 551	for (count = 0; count < 256; count++) {
 552		if (arc_proto_map[count] == arc_bcast_proto) {
 553			lp->default_proto[0] = count;
 554			break;
 555		}
 556	}
 557
 558	/* initialize buffers */
 559	atomic_set(&lp->buf_lock, 1);
 560
 561	lp->next_buf = lp->first_free_buf = 0;
 562	release_arcbuf(dev, 0);
 563	release_arcbuf(dev, 1);
 564	release_arcbuf(dev, 2);
 565	release_arcbuf(dev, 3);
 566	lp->cur_tx = lp->next_tx = -1;
 567	lp->cur_rx = -1;
 568
 569	lp->rfc1201.sequence = 1;
 570
 571	/* bring up the hardware driver */
 572	if (lp->hw.open)
 573		lp->hw.open(dev);
 574
 575	if (dev->dev_addr[0] == 0)
 576		arc_printk(D_NORMAL, dev, "WARNING!  Station address 00 is reserved for broadcasts!\n");
 577	else if (dev->dev_addr[0] == 255)
 578		arc_printk(D_NORMAL, dev, "WARNING!  Station address FF may confuse DOS networking programs!\n");
 579
 580	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 581	if (lp->hw.status(dev) & RESETflag) {
 582		arc_printk(D_DEBUG, dev, "%s: %d: %s\n",
 583			   __FILE__, __LINE__, __func__);
 584		lp->hw.command(dev, CFLAGScmd | RESETclear);
 585	}
 586
 587	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 588	/* make sure we're ready to receive IRQ's. */
 589	lp->hw.intmask(dev, 0);
 590	udelay(1);		/* give it time to set the mask before
 591				 * we reset it again. (may not even be
 592				 * necessary)
 593				 */
 594	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 595	lp->intmask = NORXflag | RECONflag;
 596	lp->hw.intmask(dev, lp->intmask);
 597	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 598
 599	netif_carrier_off(dev);
 600	netif_start_queue(dev);
 601	mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
 602
 603	arcnet_led_event(dev, ARCNET_LED_EVENT_OPEN);
 604	return 0;
 605
 606 out_module_put:
 607	module_put(lp->hw.owner);
 608	return error;
 609}
 610EXPORT_SYMBOL(arcnet_open);
 611
 612/* The inverse routine to arcnet_open - shuts down the card. */
 613int arcnet_close(struct net_device *dev)
 614{
 615	struct arcnet_local *lp = netdev_priv(dev);
 616
 617	arcnet_led_event(dev, ARCNET_LED_EVENT_STOP);
 618	del_timer_sync(&lp->timer);
 619
 620	netif_stop_queue(dev);
 621	netif_carrier_off(dev);
 622
 623	tasklet_kill(&lp->reply_tasklet);
 624
 625	/* flush TX and disable RX */
 626	lp->hw.intmask(dev, 0);
 627	lp->hw.command(dev, NOTXcmd);	/* stop transmit */
 628	lp->hw.command(dev, NORXcmd);	/* disable receive */
 629	mdelay(1);
 630
 631	/* shut down the card */
 632	lp->hw.close(dev);
 633
 634	/* reset counters */
 635	lp->reset_in_progress = 0;
 636
 637	module_put(lp->hw.owner);
 638	return 0;
 639}
 640EXPORT_SYMBOL(arcnet_close);
 641
 642static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 643			 unsigned short type, const void *daddr,
 644			 const void *saddr, unsigned len)
 645{
 646	const struct arcnet_local *lp = netdev_priv(dev);
 647	uint8_t _daddr, proto_num;
 648	struct ArcProto *proto;
 649
 650	arc_printk(D_DURING, dev,
 651		   "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 652		   saddr ? *(uint8_t *)saddr : -1,
 653		   daddr ? *(uint8_t *)daddr : -1,
 654		   type, type, len);
 655
 656	if (skb->len != 0 && len != skb->len)
 657		arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 658			   skb->len, len);
 659
 660	/* Type is host order - ? */
 661	if (type == ETH_P_ARCNET) {
 662		proto = arc_raw_proto;
 663		arc_printk(D_DEBUG, dev, "arc_raw_proto used. proto='%c'\n",
 664			   proto->suffix);
 665		_daddr = daddr ? *(uint8_t *)daddr : 0;
 666	} else if (!daddr) {
 667		/* if the dest addr isn't provided, we can't choose an
 668		 * encapsulation!  Store the packet type (eg. ETH_P_IP)
 669		 * for now, and we'll push on a real header when we do
 670		 * rebuild_header.
 671		 */
 672		*(uint16_t *)skb_push(skb, 2) = type;
 673		/* XXX: Why not use skb->mac_len? */
 674		if (skb->network_header - skb->mac_header != 2)
 675			arc_printk(D_NORMAL, dev, "arcnet_header: Yikes!  diff (%u) is not 2!\n",
 676				   skb->network_header - skb->mac_header);
 677		return -2;	/* return error -- can't transmit yet! */
 678	} else {
 679		/* otherwise, we can just add the header as usual. */
 680		_daddr = *(uint8_t *)daddr;
 681		proto_num = lp->default_proto[_daddr];
 682		proto = arc_proto_map[proto_num];
 683		arc_printk(D_DURING, dev, "building header for %02Xh using protocol '%c'\n",
 684			   proto_num, proto->suffix);
 685		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 686			arc_printk(D_DURING, dev, "actually, let's use '%c' instead.\n",
 687				   arc_bcast_proto->suffix);
 688			proto = arc_bcast_proto;
 689		}
 690	}
 691	return proto->build_header(skb, dev, type, _daddr);
 692}
 693
 694/* Called by the kernel in order to transmit a packet. */
 695netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 696			       struct net_device *dev)
 697{
 698	struct arcnet_local *lp = netdev_priv(dev);
 699	struct archdr *pkt;
 700	struct arc_rfc1201 *soft;
 701	struct ArcProto *proto;
 702	int txbuf;
 703	unsigned long flags;
 704	int retval;
 705
 706	arc_printk(D_DURING, dev,
 707		   "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 708		   lp->hw.status(dev), lp->cur_tx, lp->next_tx, skb->len, skb->protocol);
 709
 710	pkt = (struct archdr *)skb->data;
 711	soft = &pkt->soft.rfc1201;
 712	proto = arc_proto_map[soft->proto];
 713
 714	arc_printk(D_SKB_SIZE, dev, "skb: transmitting %d bytes to %02X\n",
 715		   skb->len, pkt->hard.dest);
 716	if (BUGLVL(D_SKB))
 717		arcnet_dump_skb(dev, skb, "tx");
 718
 719	/* fits in one packet? */
 720	if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 721		arc_printk(D_NORMAL, dev, "fixme: packet too large: compensating badly!\n");
 722		dev_kfree_skb(skb);
 723		return NETDEV_TX_OK;	/* don't try again */
 724	}
 725
 726	/* We're busy transmitting a packet... */
 727	netif_stop_queue(dev);
 728
 729	spin_lock_irqsave(&lp->lock, flags);
 730	lp->hw.intmask(dev, 0);
 731	if (lp->next_tx == -1)
 732		txbuf = get_arcbuf(dev);
 733	else
 734		txbuf = -1;
 735
 736	if (txbuf != -1) {
 737		lp->outgoing.skb = skb;
 738		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 739		    !proto->ack_tx) {
 740			/* done right away and we don't want to acknowledge
 741			 *  the package later - forget about it now
 742			 */
 743			dev->stats.tx_bytes += skb->len;
 744		} else {
 745			/* do it the 'split' way */
 746			lp->outgoing.proto = proto;
 747			lp->outgoing.skb = skb;
 748			lp->outgoing.pkt = pkt;
 749
 750			if (proto->continue_tx &&
 751			    proto->continue_tx(dev, txbuf)) {
 752				arc_printk(D_NORMAL, dev,
 753					   "bug! continue_tx finished the first time! (proto='%c')\n",
 754					   proto->suffix);
 755			}
 756		}
 757		retval = NETDEV_TX_OK;
 758		lp->next_tx = txbuf;
 759	} else {
 760		retval = NETDEV_TX_BUSY;
 761	}
 762
 763	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 764		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 765	/* make sure we didn't ignore a TX IRQ while we were in here */
 766	lp->hw.intmask(dev, 0);
 767
 768	arc_printk(D_DEBUG, dev, "%s: %d: %s\n", __FILE__, __LINE__, __func__);
 769	lp->intmask |= TXFREEflag | EXCNAKflag;
 770	lp->hw.intmask(dev, lp->intmask);
 771	arc_printk(D_DEBUG, dev, "%s: %d: %s, status: %x\n",
 772		   __FILE__, __LINE__, __func__, lp->hw.status(dev));
 773
 774	arcnet_led_event(dev, ARCNET_LED_EVENT_TX);
 775
 776	spin_unlock_irqrestore(&lp->lock, flags);
 777	return retval;		/* no need to try again */
 778}
 779EXPORT_SYMBOL(arcnet_send_packet);
 780
 781/* Actually start transmitting a packet that was loaded into a buffer
 782 * by prepare_tx.  This should _only_ be called by the interrupt handler.
 783 */
 784static int go_tx(struct net_device *dev)
 785{
 786	struct arcnet_local *lp = netdev_priv(dev);
 787
 788	arc_printk(D_DURING, dev, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 789		   lp->hw.status(dev), lp->intmask, lp->next_tx, lp->cur_tx);
 790
 791	if (lp->cur_tx != -1 || lp->next_tx == -1)
 792		return 0;
 793
 794	if (BUGLVL(D_TX))
 795		arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 796
 797	lp->cur_tx = lp->next_tx;
 798	lp->next_tx = -1;
 799
 800	/* start sending */
 801	lp->hw.command(dev, TXcmd | (lp->cur_tx << 3));
 802
 803	dev->stats.tx_packets++;
 804	lp->lasttrans_dest = lp->lastload_dest;
 805	lp->lastload_dest = 0;
 806	lp->excnak_pending = 0;
 807	lp->intmask |= TXFREEflag | EXCNAKflag;
 808
 809	return 1;
 810}
 811
 812/* Called by the kernel when transmit times out */
 813void arcnet_timeout(struct net_device *dev, unsigned int txqueue)
 814{
 815	unsigned long flags;
 816	struct arcnet_local *lp = netdev_priv(dev);
 817	int status = lp->hw.status(dev);
 818	char *msg;
 819
 820	spin_lock_irqsave(&lp->lock, flags);
 821	if (status & TXFREEflag) {	/* transmit _DID_ finish */
 822		msg = " - missed IRQ?";
 823	} else {
 824		msg = "";
 825		dev->stats.tx_aborted_errors++;
 826		lp->timed_out = 1;
 827		lp->hw.command(dev, NOTXcmd | (lp->cur_tx << 3));
 828	}
 829	dev->stats.tx_errors++;
 830
 831	/* make sure we didn't miss a TX or a EXC NAK IRQ */
 832	lp->hw.intmask(dev, 0);
 833	lp->intmask |= TXFREEflag | EXCNAKflag;
 834	lp->hw.intmask(dev, lp->intmask);
 835
 836	spin_unlock_irqrestore(&lp->lock, flags);
 837
 838	if (time_after(jiffies, lp->last_timeout + 10 * HZ)) {
 839		arc_printk(D_EXTRA, dev, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 840			   msg, status, lp->intmask, lp->lasttrans_dest);
 841		lp->last_timeout = jiffies;
 842	}
 843
 844	if (lp->cur_tx == -1)
 845		netif_wake_queue(dev);
 846}
 847EXPORT_SYMBOL(arcnet_timeout);
 848
 849/* The typical workload of the driver: Handle the network interface
 850 * interrupts. Establish which device needs attention, and call the correct
 851 * chipset interrupt handler.
 852 */
 853irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 854{
 855	struct net_device *dev = dev_id;
 856	struct arcnet_local *lp;
 857	int recbuf, status, diagstatus, didsomething, boguscount;
 858	unsigned long flags;
 859	int retval = IRQ_NONE;
 860
 861	arc_printk(D_DURING, dev, "\n");
 862
 863	arc_printk(D_DURING, dev, "in arcnet_interrupt\n");
 864
 865	lp = netdev_priv(dev);
 866	BUG_ON(!lp);
 867
 868	spin_lock_irqsave(&lp->lock, flags);
 869
 870	if (lp->reset_in_progress)
 871		goto out;
 872
 873	/* RESET flag was enabled - if device is not running, we must
 874	 * clear it right away (but nothing else).
 875	 */
 876	if (!netif_running(dev)) {
 877		if (lp->hw.status(dev) & RESETflag)
 878			lp->hw.command(dev, CFLAGScmd | RESETclear);
 879		lp->hw.intmask(dev, 0);
 880		spin_unlock_irqrestore(&lp->lock, flags);
 881		return retval;
 882	}
 883
 884	arc_printk(D_DURING, dev, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 885		   lp->hw.status(dev), lp->intmask);
 886
 887	boguscount = 5;
 888	do {
 889		status = lp->hw.status(dev);
 890		diagstatus = (status >> 8) & 0xFF;
 891
 892		arc_printk(D_DEBUG, dev, "%s: %d: %s: status=%x\n",
 893			   __FILE__, __LINE__, __func__, status);
 894		didsomething = 0;
 895
 896		/* RESET flag was enabled - card is resetting and if RX is
 897		 * disabled, it's NOT because we just got a packet.
 898		 *
 899		 * The card is in an undefined state.
 900		 * Clear it out and start over.
 901		 */
 902		if (status & RESETflag) {
 903			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 904				   status);
 905
 906			lp->reset_in_progress = 1;
 907			netif_stop_queue(dev);
 908			netif_carrier_off(dev);
 909			schedule_work(&lp->reset_work);
 910
 911			/* get out of the interrupt handler! */
 912			goto out;
 913		}
 914		/* RX is inhibited - we must have received something.
 915		 * Prepare to receive into the next buffer.
 916		 *
 917		 * We don't actually copy the received packet from the card
 918		 * until after the transmit handler runs (and possibly
 919		 * launches the next tx); this should improve latency slightly
 920		 * if we get both types of interrupts at once.
 921		 */
 922		recbuf = -1;
 923		if (status & lp->intmask & NORXflag) {
 924			recbuf = lp->cur_rx;
 925			arc_printk(D_DURING, dev, "Buffer #%d: receive irq (status=%Xh)\n",
 926				   recbuf, status);
 927
 928			lp->cur_rx = get_arcbuf(dev);
 929			if (lp->cur_rx != -1) {
 930				arc_printk(D_DURING, dev, "enabling receive to buffer #%d\n",
 931					   lp->cur_rx);
 932				lp->hw.command(dev, RXcmd | (lp->cur_rx << 3) | RXbcasts);
 933			}
 934			didsomething++;
 935		}
 936
 937		if ((diagstatus & EXCNAKflag)) {
 938			arc_printk(D_DURING, dev, "EXCNAK IRQ (diagstat=%Xh)\n",
 939				   diagstatus);
 940
 941			lp->hw.command(dev, NOTXcmd);      /* disable transmit */
 942			lp->excnak_pending = 1;
 943
 944			lp->hw.command(dev, EXCNAKclear);
 945			lp->intmask &= ~(EXCNAKflag);
 946			didsomething++;
 947		}
 948
 949		/* a transmit finished, and we're interested in it. */
 950		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 951			int ackstatus;
 952			lp->intmask &= ~(TXFREEflag | EXCNAKflag);
 953
 954			if (status & TXACKflag)
 955				ackstatus = 2;
 956			else if (lp->excnak_pending)
 957				ackstatus = 1;
 958			else
 959				ackstatus = 0;
 960
 961			arc_printk(D_DURING, dev, "TX IRQ (stat=%Xh)\n",
 962				   status);
 963
 964			if (lp->cur_tx != -1 && !lp->timed_out) {
 965				if (!(status & TXACKflag)) {
 966					if (lp->lasttrans_dest != 0) {
 967						arc_printk(D_EXTRA, dev,
 968							   "transmit was not acknowledged! (status=%Xh, dest=%02Xh)\n",
 969							   status,
 970							   lp->lasttrans_dest);
 971						dev->stats.tx_errors++;
 972						dev->stats.tx_carrier_errors++;
 973					} else {
 974						arc_printk(D_DURING, dev,
 975							   "broadcast was not acknowledged; that's normal (status=%Xh, dest=%02Xh)\n",
 976							   status,
 977							   lp->lasttrans_dest);
 978					}
 979				}
 980
 981				if (lp->outgoing.proto &&
 982				    lp->outgoing.proto->ack_tx) {
 983					lp->outgoing.proto
 984						->ack_tx(dev, ackstatus);
 985				}
 986				lp->reply_status = ackstatus;
 987				tasklet_hi_schedule(&lp->reply_tasklet);
 988			}
 989			if (lp->cur_tx != -1)
 990				release_arcbuf(dev, lp->cur_tx);
 991
 992			lp->cur_tx = -1;
 993			lp->timed_out = 0;
 994			didsomething++;
 995
 996			/* send another packet if there is one */
 997			go_tx(dev);
 998
 999			/* continue a split packet, if any */
1000			if (lp->outgoing.proto &&
1001			    lp->outgoing.proto->continue_tx) {
1002				int txbuf = get_arcbuf(dev);
1003
1004				if (txbuf != -1) {
1005					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
1006						/* that was the last segment */
1007						dev->stats.tx_bytes += lp->outgoing.skb->len;
1008						if (!lp->outgoing.proto->ack_tx) {
1009							dev_kfree_skb_irq(lp->outgoing.skb);
1010							lp->outgoing.proto = NULL;
1011						}
1012					}
1013					lp->next_tx = txbuf;
1014				}
1015			}
1016			/* inform upper layers of idleness, if necessary */
1017			if (lp->cur_tx == -1)
1018				netif_wake_queue(dev);
1019		}
1020		/* now process the received packet, if any */
1021		if (recbuf != -1) {
1022			if (BUGLVL(D_RX))
1023				arcnet_dump_packet(dev, recbuf, "rx irq", 0);
1024
1025			arcnet_rx(dev, recbuf);
1026			release_arcbuf(dev, recbuf);
1027
1028			didsomething++;
1029		}
1030		if (status & lp->intmask & RECONflag) {
1031			lp->hw.command(dev, CFLAGScmd | CONFIGclear);
1032			dev->stats.tx_carrier_errors++;
1033
1034			arc_printk(D_RECON, dev, "Network reconfiguration detected (status=%Xh)\n",
1035				   status);
1036			if (netif_carrier_ok(dev)) {
1037				netif_carrier_off(dev);
1038				netdev_info(dev, "link down\n");
1039			}
1040			mod_timer(&lp->timer, jiffies + msecs_to_jiffies(1000));
1041
1042			arcnet_led_event(dev, ARCNET_LED_EVENT_RECON);
1043			/* MYRECON bit is at bit 7 of diagstatus */
1044			if (diagstatus & 0x80)
1045				arc_printk(D_RECON, dev, "Put out that recon myself\n");
1046
1047			/* is the RECON info empty or old? */
1048			if (!lp->first_recon || !lp->last_recon ||
1049			    time_after(jiffies, lp->last_recon + HZ * 10)) {
1050				if (lp->network_down)
1051					arc_printk(D_NORMAL, dev, "reconfiguration detected: cabling restored?\n");
1052				lp->first_recon = lp->last_recon = jiffies;
1053				lp->num_recons = lp->network_down = 0;
1054
1055				arc_printk(D_DURING, dev, "recon: clearing counters.\n");
1056			} else {	/* add to current RECON counter */
1057				lp->last_recon = jiffies;
1058				lp->num_recons++;
1059
1060				arc_printk(D_DURING, dev, "recon: counter=%d, time=%lds, net=%d\n",
1061					   lp->num_recons,
1062					   (lp->last_recon - lp->first_recon) / HZ,
1063					   lp->network_down);
1064
1065				/* if network is marked up;
1066				 * and first_recon and last_recon are 60+ apart;
1067				 * and the average no. of recons counted is
1068				 *    > RECON_THRESHOLD/min;
1069				 * then print a warning message.
1070				 */
1071				if (!lp->network_down &&
1072				    (lp->last_recon - lp->first_recon) <= HZ * 60 &&
1073				    lp->num_recons >= RECON_THRESHOLD) {
1074					lp->network_down = 1;
1075					arc_printk(D_NORMAL, dev, "many reconfigurations detected: cabling problem?\n");
1076				} else if (!lp->network_down &&
1077					   lp->last_recon - lp->first_recon > HZ * 60) {
1078					/* reset counters if we've gone for
1079					 *  over a minute.
1080					 */
1081					lp->first_recon = lp->last_recon;
1082					lp->num_recons = 1;
1083				}
1084			}
1085		} else if (lp->network_down &&
1086			   time_after(jiffies, lp->last_recon + HZ * 10)) {
1087			if (lp->network_down)
1088				arc_printk(D_NORMAL, dev, "cabling restored?\n");
1089			lp->first_recon = lp->last_recon = 0;
1090			lp->num_recons = lp->network_down = 0;
1091
1092			arc_printk(D_DURING, dev, "not recon: clearing counters anyway.\n");
1093			netif_carrier_on(dev);
1094		}
1095
1096		if (didsomething)
1097			retval |= IRQ_HANDLED;
1098	} while (--boguscount && didsomething);
1099
1100	arc_printk(D_DURING, dev, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
1101		   lp->hw.status(dev), boguscount);
1102	arc_printk(D_DURING, dev, "\n");
1103
1104	lp->hw.intmask(dev, 0);
1105	udelay(1);
1106	lp->hw.intmask(dev, lp->intmask);
1107
1108out:
1109	spin_unlock_irqrestore(&lp->lock, flags);
1110	return retval;
1111}
1112EXPORT_SYMBOL(arcnet_interrupt);
1113
1114/* This is a generic packet receiver that calls arcnet??_rx depending on the
1115 * protocol ID found.
1116 */
1117static void arcnet_rx(struct net_device *dev, int bufnum)
1118{
1119	struct arcnet_local *lp = netdev_priv(dev);
1120	union {
1121		struct archdr pkt;
1122		char buf[512];
1123	} rxdata;
1124	struct arc_rfc1201 *soft;
1125	int length, ofs;
1126
1127	soft = &rxdata.pkt.soft.rfc1201;
1128
1129	lp->hw.copy_from_card(dev, bufnum, 0, &rxdata.pkt, ARC_HDR_SIZE);
1130	if (rxdata.pkt.hard.offset[0]) {
1131		ofs = rxdata.pkt.hard.offset[0];
1132		length = 256 - ofs;
1133	} else {
1134		ofs = rxdata.pkt.hard.offset[1];
1135		length = 512 - ofs;
1136	}
1137
1138	/* get the full header, if possible */
1139	if (sizeof(rxdata.pkt.soft) <= length) {
1140		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(rxdata.pkt.soft));
1141	} else {
1142		memset(&rxdata.pkt.soft, 0, sizeof(rxdata.pkt.soft));
1143		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1144	}
1145
1146	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1147		   bufnum, rxdata.pkt.hard.source, rxdata.pkt.hard.dest, length);
1148
1149	dev->stats.rx_packets++;
1150	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1151
1152	/* call the right receiver for the protocol */
1153	if (arc_proto_map[soft->proto]->is_ip) {
1154		if (BUGLVL(D_PROTO)) {
1155			struct ArcProto
1156			*oldp = arc_proto_map[lp->default_proto[rxdata.pkt.hard.source]],
1157			*newp = arc_proto_map[soft->proto];
1158
1159			if (oldp != newp) {
1160				arc_printk(D_PROTO, dev,
1161					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1162					   soft->proto, rxdata.pkt.hard.source,
1163					   newp->suffix, oldp->suffix);
1164			}
1165		}
1166
1167		/* broadcasts will always be done with the last-used encap. */
1168		lp->default_proto[0] = soft->proto;
1169
1170		/* in striking contrast, the following isn't a hack. */
1171		lp->default_proto[rxdata.pkt.hard.source] = soft->proto;
1172	}
1173	/* call the protocol-specific receiver. */
1174	arc_proto_map[soft->proto]->rx(dev, bufnum, &rxdata.pkt, length);
1175}
1176
1177static void null_rx(struct net_device *dev, int bufnum,
1178		    struct archdr *pkthdr, int length)
1179{
1180	arc_printk(D_PROTO, dev,
1181		   "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1182		   pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1183}
1184
1185static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1186			     unsigned short type, uint8_t daddr)
1187{
1188	struct arcnet_local *lp = netdev_priv(dev);
1189
1190	arc_printk(D_PROTO, dev,
1191		   "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1192		   lp->default_proto[daddr]);
1193
1194	/* always fails */
1195	return 0;
1196}
1197
1198/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1199static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1200			   int length, int bufnum)
1201{
1202	struct arcnet_local *lp = netdev_priv(dev);
1203	struct arc_hardware newpkt;
1204
1205	arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1206
1207	/* send a packet to myself -- will never get received, of course */
1208	newpkt.source = newpkt.dest = dev->dev_addr[0];
1209
1210	/* only one byte of actual data (and it's random) */
1211	newpkt.offset[0] = 0xFF;
1212
1213	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1214
1215	return 1;		/* done */
1216}