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v4.17
   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	struct archdr pkt;
1067	struct arc_rfc1201 *soft;
1068	int length, ofs;
1069
1070	soft = &pkt.soft.rfc1201;
1071
1072	lp->hw.copy_from_card(dev, bufnum, 0, &pkt, ARC_HDR_SIZE);
1073	if (pkt.hard.offset[0]) {
1074		ofs = pkt.hard.offset[0];
1075		length = 256 - ofs;
1076	} else {
1077		ofs = pkt.hard.offset[1];
1078		length = 512 - ofs;
1079	}
1080
1081	/* get the full header, if possible */
1082	if (sizeof(pkt.soft) <= length) {
1083		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft));
1084	} else {
1085		memset(&pkt.soft, 0, sizeof(pkt.soft));
1086		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1087	}
1088
1089	arc_printk(D_DURING, dev, "Buffer #%d: received packet from %02Xh to %02Xh (%d+4 bytes)\n",
1090		   bufnum, pkt.hard.source, pkt.hard.dest, length);
 
1091
1092	dev->stats.rx_packets++;
1093	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1094
1095	/* call the right receiver for the protocol */
1096	if (arc_proto_map[soft->proto]->is_ip) {
1097		if (BUGLVL(D_PROTO)) {
1098			struct ArcProto
1099			*oldp = arc_proto_map[lp->default_proto[pkt.hard.source]],
1100			*newp = arc_proto_map[soft->proto];
1101
1102			if (oldp != newp) {
1103				arc_printk(D_PROTO, dev,
1104					   "got protocol %02Xh; encap for host %02Xh is now '%c' (was '%c')\n",
1105					   soft->proto, pkt.hard.source,
1106					   newp->suffix, oldp->suffix);
1107			}
1108		}
1109
1110		/* broadcasts will always be done with the last-used encap. */
1111		lp->default_proto[0] = soft->proto;
1112
1113		/* in striking contrast, the following isn't a hack. */
1114		lp->default_proto[pkt.hard.source] = soft->proto;
1115	}
1116	/* call the protocol-specific receiver. */
1117	arc_proto_map[soft->proto]->rx(dev, bufnum, &pkt, length);
1118}
1119
 
1120static void null_rx(struct net_device *dev, int bufnum,
1121		    struct archdr *pkthdr, int length)
1122{
1123	arc_printk(D_PROTO, dev,
1124		   "rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1125		   pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1126}
1127
 
1128static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1129			     unsigned short type, uint8_t daddr)
1130{
1131	struct arcnet_local *lp = netdev_priv(dev);
1132
1133	arc_printk(D_PROTO, dev,
1134		   "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1135		   lp->default_proto[daddr]);
1136
1137	/* always fails */
1138	return 0;
1139}
1140
 
1141/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1142static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1143			   int length, int bufnum)
1144{
1145	struct arcnet_local *lp = netdev_priv(dev);
1146	struct arc_hardware newpkt;
1147
1148	arc_printk(D_PROTO, dev, "tx: no encap for this host; load a protocol driver.\n");
1149
1150	/* send a packet to myself -- will never get received, of course */
1151	newpkt.source = newpkt.dest = dev->dev_addr[0];
1152
1153	/* only one byte of actual data (and it's random) */
1154	newpkt.offset[0] = 0xFF;
1155
1156	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1157
1158	return 1;		/* done */
1159}
v3.1
   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 VERSION "arcnet: v3.94 BETA 2007/02/08 - by Avery Pennarun et al.\n"
  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/arcdevice.h>
  54#include <linux/jiffies.h>
 
 
 
 
 
 
  55
  56/* "do nothing" functions for protocol drivers */
  57static void null_rx(struct net_device *dev, int bufnum,
  58		    struct archdr *pkthdr, int length);
  59static int null_build_header(struct sk_buff *skb, struct net_device *dev,
  60			     unsigned short type, uint8_t daddr);
  61static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
  62			   int length, int bufnum);
  63
  64static void arcnet_rx(struct net_device *dev, int bufnum);
  65
  66/*
  67 * one ArcProto per possible proto ID.  None of the elements of
  68 * arc_proto_map are allowed to be NULL; they will get set to
  69 * arc_proto_default instead.  It also must not be NULL; if you would like
  70 * to set it to NULL, set it to &arc_proto_null instead.
  71 */
  72 struct ArcProto *arc_proto_map[256], *arc_proto_default,
  73   *arc_bcast_proto, *arc_raw_proto;
 
 
 
 
 
 
  74
  75static struct ArcProto arc_proto_null =
  76{
 
 
  77	.suffix		= '?',
  78	.mtu		= XMTU,
  79	.is_ip          = 0,
  80	.rx		= null_rx,
  81	.build_header	= null_build_header,
  82	.prepare_tx	= null_prepare_tx,
  83	.continue_tx    = NULL,
  84	.ack_tx         = NULL
  85};
  86
  87/* Exported function prototypes */
  88int arcnet_debug = ARCNET_DEBUG;
  89
  90EXPORT_SYMBOL(arc_proto_map);
  91EXPORT_SYMBOL(arc_proto_default);
  92EXPORT_SYMBOL(arc_bcast_proto);
  93EXPORT_SYMBOL(arc_raw_proto);
  94EXPORT_SYMBOL(arcnet_unregister_proto);
  95EXPORT_SYMBOL(arcnet_debug);
  96EXPORT_SYMBOL(alloc_arcdev);
  97EXPORT_SYMBOL(arcnet_interrupt);
  98EXPORT_SYMBOL(arcnet_open);
  99EXPORT_SYMBOL(arcnet_close);
 100EXPORT_SYMBOL(arcnet_send_packet);
 101EXPORT_SYMBOL(arcnet_timeout);
 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 arcnet_rebuild_header(struct sk_buff *skb);
 108static int go_tx(struct net_device *dev);
 109
 110static int debug = ARCNET_DEBUG;
 111module_param(debug, int, 0);
 112MODULE_LICENSE("GPL");
 113
 114static int __init arcnet_init(void)
 115{
 116	int count;
 117
 118	arcnet_debug = debug;
 119
 120	printk("arcnet loaded.\n");
 121
 122#ifdef ALPHA_WARNING
 123	BUGLVL(D_EXTRA) {
 124		printk("arcnet: ***\n"
 125		"arcnet: * Read arcnet.txt for important release notes!\n"
 126		       "arcnet: *\n"
 127		       "arcnet: * This is an ALPHA version! (Last stable release: v3.02)  E-mail\n"
 128		       "arcnet: * me if you have any questions, comments, or bug reports.\n"
 129		       "arcnet: ***\n");
 130	}
 131#endif
 132
 133	/* initialize the protocol map */
 134	arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
 135	for (count = 0; count < 256; count++)
 136		arc_proto_map[count] = arc_proto_default;
 137
 138	BUGLVL(D_DURING)
 139	    printk("arcnet: struct sizes: %Zd %Zd %Zd %Zd %Zd\n",
 140		 sizeof(struct arc_hardware), sizeof(struct arc_rfc1201),
 141		sizeof(struct arc_rfc1051), sizeof(struct arc_eth_encap),
 142		   sizeof(struct archdr));
 
 
 143
 144	return 0;
 145}
 146
 147static void __exit arcnet_exit(void)
 148{
 149}
 150
 151module_init(arcnet_init);
 152module_exit(arcnet_exit);
 153
 154/*
 155 * Dump the contents of an sk_buff
 156 */
 157#if ARCNET_DEBUG_MAX & D_SKB
 158void arcnet_dump_skb(struct net_device *dev,
 159		     struct sk_buff *skb, char *desc)
 160{
 161	char hdr[32];
 162
 163	/* dump the packet */
 164	snprintf(hdr, sizeof(hdr), "%6s:%s skb->data:", dev->name, desc);
 165	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 166		       16, 1, skb->data, skb->len, true);
 167}
 168
 169EXPORT_SYMBOL(arcnet_dump_skb);
 170#endif
 171
 172
 173/*
 174 * Dump the contents of an ARCnet buffer
 175 */
 176#if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
 177static void arcnet_dump_packet(struct net_device *dev, int bufnum,
 178			       char *desc, int take_arcnet_lock)
 179{
 180	struct arcnet_local *lp = netdev_priv(dev);
 181	int i, length;
 182	unsigned long flags = 0;
 183	static uint8_t buf[512];
 184	char hdr[32];
 185
 186	/* hw.copy_from_card expects IRQ context so take the IRQ lock
 187	   to keep it single threaded */
 188	if(take_arcnet_lock)
 
 189		spin_lock_irqsave(&lp->lock, flags);
 190
 191	lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
 192	if(take_arcnet_lock)
 193		spin_unlock_irqrestore(&lp->lock, flags);
 194
 195	/* if the offset[0] byte is nonzero, this is a 256-byte packet */
 196	length = (buf[2] ? 256 : 512);
 197
 198	/* dump the packet */
 199	snprintf(hdr, sizeof(hdr), "%6s:%s packet dump:", dev->name, desc);
 200	print_hex_dump(KERN_DEBUG, hdr, DUMP_PREFIX_OFFSET,
 201		       16, 1, buf, length, true);
 202}
 203
 204#else
 205
 206#define arcnet_dump_packet(dev, bufnum, desc,take_arcnet_lock) do { } while (0)
 207
 208#endif
 209
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 210
 211/*
 212 * Unregister a protocol driver from the arc_proto_map.  Protocol drivers
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 213 * are responsible for registering themselves, but the unregister routine
 214 * is pretty generic so we'll do it here.
 215 */
 216void arcnet_unregister_proto(struct ArcProto *proto)
 217{
 218	int count;
 219
 220	if (arc_proto_default == proto)
 221		arc_proto_default = &arc_proto_null;
 222	if (arc_bcast_proto == proto)
 223		arc_bcast_proto = arc_proto_default;
 224	if (arc_raw_proto == proto)
 225		arc_raw_proto = arc_proto_default;
 226
 227	for (count = 0; count < 256; count++) {
 228		if (arc_proto_map[count] == proto)
 229			arc_proto_map[count] = arc_proto_default;
 230	}
 231}
 
 232
 233
 234/*
 235 * Add a buffer to the queue.  Only the interrupt handler is allowed to do
 236 * this, unless interrupts are disabled.
 237 * 
 238 * Note: we don't check for a full queue, since there aren't enough buffers
 239 * to more than fill it.
 240 */
 241static void release_arcbuf(struct net_device *dev, int bufnum)
 242{
 243	struct arcnet_local *lp = netdev_priv(dev);
 244	int i;
 245
 246	lp->buf_queue[lp->first_free_buf++] = bufnum;
 247	lp->first_free_buf %= 5;
 248
 249	BUGLVL(D_DURING) {
 250		BUGMSG(D_DURING, "release_arcbuf: freed #%d; buffer queue is now: ",
 251		       bufnum);
 252		for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5)
 253			BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]);
 254		BUGMSG2(D_DURING, "\n");
 255	}
 256}
 257
 258
 259/*
 260 * Get a buffer from the queue.  If this returns -1, there are no buffers
 261 * available.
 262 */
 263static int get_arcbuf(struct net_device *dev)
 264{
 265	struct arcnet_local *lp = netdev_priv(dev);
 266	int buf = -1, i;
 267
 268	if (!atomic_dec_and_test(&lp->buf_lock)) {
 269		/* already in this function */
 270		BUGMSG(D_NORMAL, "get_arcbuf: overlap (%d)!\n",
 271		       lp->buf_lock.counter);
 272	}
 273	else {			/* we can continue */
 274		if (lp->next_buf >= 5)
 275			lp->next_buf -= 5;
 276
 277		if (lp->next_buf == lp->first_free_buf)
 278			BUGMSG(D_NORMAL, "get_arcbuf: BUG: no buffers are available??\n");
 279		else {
 280			buf = lp->buf_queue[lp->next_buf++];
 281			lp->next_buf %= 5;
 282		}
 283	}
 284
 285
 286	BUGLVL(D_DURING) {
 287		BUGMSG(D_DURING, "get_arcbuf: got #%d; buffer queue is now: ", buf);
 288		for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5)
 289			BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]);
 290		BUGMSG2(D_DURING, "\n");
 291	}
 292
 293	atomic_inc(&lp->buf_lock);
 294	return buf;
 295}
 296
 297
 298static int choose_mtu(void)
 299{
 300	int count, mtu = 65535;
 301
 302	/* choose the smallest MTU of all available encaps */
 303	for (count = 0; count < 256; count++) {
 304		if (arc_proto_map[count] != &arc_proto_null &&
 305		    arc_proto_map[count]->mtu < mtu) {
 306			mtu = arc_proto_map[count]->mtu;
 307		}
 308	}
 309
 310	return mtu == 65535 ? XMTU : mtu;
 311}
 312
 313static const struct header_ops arcnet_header_ops = {
 314	.create = arcnet_header,
 315	.rebuild = arcnet_rebuild_header,
 316};
 317
 318static const struct net_device_ops arcnet_netdev_ops = {
 319	.ndo_open	= arcnet_open,
 320	.ndo_stop	= arcnet_close,
 321	.ndo_start_xmit = arcnet_send_packet,
 322	.ndo_tx_timeout = arcnet_timeout,
 323};
 324
 325/* Setup a struct device for ARCnet. */
 326static void arcdev_setup(struct net_device *dev)
 327{
 328	dev->type = ARPHRD_ARCNET;
 329	dev->netdev_ops = &arcnet_netdev_ops;
 330	dev->header_ops = &arcnet_header_ops;
 331	dev->hard_header_len = sizeof(struct archdr);
 332	dev->mtu = choose_mtu();
 333
 334	dev->addr_len = ARCNET_ALEN;
 335	dev->tx_queue_len = 100;
 336	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
 337	dev->watchdog_timeo = TX_TIMEOUT;
 338
 339	/* New-style flags. */
 340	dev->flags = IFF_BROADCAST;
 
 
 
 
 
 
 341
 
 
 
 
 342}
 343
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 344struct net_device *alloc_arcdev(const char *name)
 345{
 346	struct net_device *dev;
 347
 348	dev = alloc_netdev(sizeof(struct arcnet_local),
 349			   name && *name ? name : "arc%d", arcdev_setup);
 350	if(dev) {
 
 351		struct arcnet_local *lp = netdev_priv(dev);
 
 
 352		spin_lock_init(&lp->lock);
 
 353	}
 354
 355	return dev;
 356}
 
 357
 358/*
 359 * Open/initialize the board.  This is called sometime after booting when
 360 * the 'ifconfig' program is run.
 361 *
 362 * This routine should set everything up anew at each open, even registers
 363 * that "should" only need to be set once at boot, so that there is
 364 * non-reboot way to recover if something goes wrong.
 365 */
 366int arcnet_open(struct net_device *dev)
 367{
 368	struct arcnet_local *lp = netdev_priv(dev);
 369	int count, newmtu, error;
 370
 371	BUGMSG(D_INIT,"opened.");
 372
 373	if (!try_module_get(lp->hw.owner))
 374		return -ENODEV;
 375
 376	BUGLVL(D_PROTO) {
 377		BUGMSG(D_PROTO, "protocol map (default is '%c'): ",
 378		       arc_proto_default->suffix);
 379		for (count = 0; count < 256; count++)
 380			BUGMSG2(D_PROTO, "%c", arc_proto_map[count]->suffix);
 381		BUGMSG2(D_PROTO, "\n");
 382	}
 383
 
 
 384
 385	BUGMSG(D_INIT, "arcnet_open: resetting card.\n");
 386
 387	/* try to put the card in a defined state - if it fails the first
 388	 * time, actually reset it.
 389	 */
 390	error = -ENODEV;
 391	if (ARCRESET(0) && ARCRESET(1))
 392		goto out_module_put;
 393
 394	newmtu = choose_mtu();
 395	if (newmtu < dev->mtu)
 396		dev->mtu = newmtu;
 397
 398	BUGMSG(D_INIT, "arcnet_open: mtu: %d.\n", dev->mtu);
 399
 400	/* autodetect the encapsulation for each host. */
 401	memset(lp->default_proto, 0, sizeof(lp->default_proto));
 402
 403	/* the broadcast address is special - use the 'bcast' protocol */
 404	for (count = 0; count < 256; count++) {
 405		if (arc_proto_map[count] == arc_bcast_proto) {
 406			lp->default_proto[0] = count;
 407			break;
 408		}
 409	}
 410
 411	/* initialize buffers */
 412	atomic_set(&lp->buf_lock, 1);
 413
 414	lp->next_buf = lp->first_free_buf = 0;
 415	release_arcbuf(dev, 0);
 416	release_arcbuf(dev, 1);
 417	release_arcbuf(dev, 2);
 418	release_arcbuf(dev, 3);
 419	lp->cur_tx = lp->next_tx = -1;
 420	lp->cur_rx = -1;
 421
 422	lp->rfc1201.sequence = 1;
 423
 424	/* bring up the hardware driver */
 425	if (lp->hw.open)
 426		lp->hw.open(dev);
 427
 428	if (dev->dev_addr[0] == 0)
 429		BUGMSG(D_NORMAL, "WARNING!  Station address 00 is reserved "
 430		       "for broadcasts!\n");
 431	else if (dev->dev_addr[0] == 255)
 432		BUGMSG(D_NORMAL, "WARNING!  Station address FF may confuse "
 433		       "DOS networking programs!\n");
 434
 435	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 436	if (ASTATUS() & RESETflag) {
 437	  	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 438		ACOMMAND(CFLAGScmd | RESETclear);
 
 439	}
 440
 441
 442	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 443	/* make sure we're ready to receive IRQ's. */
 444	AINTMASK(0);
 445	udelay(1);		/* give it time to set the mask before
 446				 * we reset it again. (may not even be
 447				 * necessary)
 448				 */
 449	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 450	lp->intmask = NORXflag | RECONflag;
 451	AINTMASK(lp->intmask);
 452	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 453
 
 454	netif_start_queue(dev);
 
 455
 
 456	return 0;
 457
 458 out_module_put:
 459	module_put(lp->hw.owner);
 460	return error;
 461}
 462
 463
 464/* The inverse routine to arcnet_open - shuts down the card. */
 465int arcnet_close(struct net_device *dev)
 466{
 467	struct arcnet_local *lp = netdev_priv(dev);
 468
 
 
 
 469	netif_stop_queue(dev);
 
 
 
 470
 471	/* flush TX and disable RX */
 472	AINTMASK(0);
 473	ACOMMAND(NOTXcmd);	/* stop transmit */
 474	ACOMMAND(NORXcmd);	/* disable receive */
 475	mdelay(1);
 476
 477	/* shut down the card */
 478	lp->hw.close(dev);
 479	module_put(lp->hw.owner);
 480	return 0;
 481}
 482
 483
 484static int arcnet_header(struct sk_buff *skb, struct net_device *dev,
 485			 unsigned short type, const void *daddr,
 486			 const void *saddr, unsigned len)
 487{
 488	const struct arcnet_local *lp = netdev_priv(dev);
 489	uint8_t _daddr, proto_num;
 490	struct ArcProto *proto;
 491
 492	BUGMSG(D_DURING,
 493	    "create header from %d to %d; protocol %d (%Xh); size %u.\n",
 494	       saddr ? *(uint8_t *) saddr : -1,
 495	       daddr ? *(uint8_t *) daddr : -1,
 496	       type, type, len);
 497
 498	if (skb->len!=0 && len != skb->len)
 499		BUGMSG(D_NORMAL, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 500		       skb->len, len);
 501
 502
 503  	/* Type is host order - ? */
 504  	if(type == ETH_P_ARCNET) {
 505  		proto = arc_raw_proto;
 506  		BUGMSG(D_DEBUG, "arc_raw_proto used. proto='%c'\n",proto->suffix);
 507  		_daddr = daddr ? *(uint8_t *) daddr : 0;
 508  	}
 509	else if (!daddr) {
 510		/*
 511		 * if the dest addr isn't provided, we can't choose an encapsulation!
 512		 * Store the packet type (eg. ETH_P_IP) for now, and we'll push on a
 513		 * real header when we do rebuild_header.
 514		 */
 515		*(uint16_t *) skb_push(skb, 2) = type;
 516		/*
 517		 * XXX: Why not use skb->mac_len?
 518		 */
 
 
 519		if (skb->network_header - skb->mac_header != 2)
 520			BUGMSG(D_NORMAL, "arcnet_header: Yikes!  diff (%d) is not 2!\n",
 521			       (int)(skb->network_header - skb->mac_header));
 522		return -2;	/* return error -- can't transmit yet! */
 523	}
 524	else {
 525		/* otherwise, we can just add the header as usual. */
 526		_daddr = *(uint8_t *) daddr;
 527		proto_num = lp->default_proto[_daddr];
 528		proto = arc_proto_map[proto_num];
 529		BUGMSG(D_DURING, "building header for %02Xh using protocol '%c'\n",
 530		       proto_num, proto->suffix);
 531		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
 532			BUGMSG(D_DURING, "actually, let's use '%c' instead.\n",
 533			       arc_bcast_proto->suffix);
 534			proto = arc_bcast_proto;
 535		}
 536	}
 537	return proto->build_header(skb, dev, type, _daddr);
 538}
 539
 540
 541/* 
 542 * Rebuild the ARCnet hard header. This is called after an ARP (or in the
 543 * future other address resolution) has completed on this sk_buff. We now
 544 * let ARP fill in the destination field.
 545 */
 546static int arcnet_rebuild_header(struct sk_buff *skb)
 547{
 548	struct net_device *dev = skb->dev;
 549	struct arcnet_local *lp = netdev_priv(dev);
 550	int status = 0;		/* default is failure */
 551	unsigned short type;
 552	uint8_t daddr=0;
 553	struct ArcProto *proto;
 554	/*
 555	 * XXX: Why not use skb->mac_len?
 556	 */
 557	if (skb->network_header - skb->mac_header != 2) {
 558		BUGMSG(D_NORMAL,
 559		       "rebuild_header: shouldn't be here! (hdrsize=%d)\n",
 560		       (int)(skb->network_header - skb->mac_header));
 561		return 0;
 562	}
 563	type = *(uint16_t *) skb_pull(skb, 2);
 564	BUGMSG(D_DURING, "rebuild header for protocol %Xh\n", type);
 565
 566	if (type == ETH_P_IP) {
 567#ifdef CONFIG_INET
 568		BUGMSG(D_DURING, "rebuild header for ethernet protocol %Xh\n", type);
 569		status = arp_find(&daddr, skb) ? 1 : 0;
 570		BUGMSG(D_DURING, " rebuilt: dest is %d; protocol %Xh\n",
 571		       daddr, type);
 572#endif
 573	} else {
 574		BUGMSG(D_NORMAL,
 575		       "I don't understand ethernet protocol %Xh addresses!\n", type);
 576		dev->stats.tx_errors++;
 577		dev->stats.tx_aborted_errors++;
 578	}
 579
 580	/* if we couldn't resolve the address... give up. */
 581	if (!status)
 582		return 0;
 583
 584	/* add the _real_ header this time! */
 585	proto = arc_proto_map[lp->default_proto[daddr]];
 586	proto->build_header(skb, dev, type, daddr);
 587
 588	return 1;		/* success */
 589}
 590
 591
 592
 593/* Called by the kernel in order to transmit a packet. */
 594netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
 595				     struct net_device *dev)
 596{
 597	struct arcnet_local *lp = netdev_priv(dev);
 598	struct archdr *pkt;
 599	struct arc_rfc1201 *soft;
 600	struct ArcProto *proto;
 601	int txbuf;
 602	unsigned long flags;
 603	int freeskb, retval;
 604
 605	BUGMSG(D_DURING,
 606	       "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
 607	       ASTATUS(), lp->cur_tx, lp->next_tx, skb->len,skb->protocol);
 608
 609	pkt = (struct archdr *) skb->data;
 610	soft = &pkt->soft.rfc1201;
 611	proto = arc_proto_map[soft->proto];
 612
 613	BUGMSG(D_SKB_SIZE, "skb: transmitting %d bytes to %02X\n",
 614		skb->len, pkt->hard.dest);
 615	BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "tx");
 
 616
 617	/* fits in one packet? */
 618	if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) {
 619		BUGMSG(D_NORMAL, "fixme: packet too large: compensating badly!\n");
 620		dev_kfree_skb(skb);
 621		return NETDEV_TX_OK;	/* don't try again */
 622	}
 623
 624	/* We're busy transmitting a packet... */
 625	netif_stop_queue(dev);
 626
 627	spin_lock_irqsave(&lp->lock, flags);
 628	AINTMASK(0);
 629	if(lp->next_tx == -1)
 630		txbuf = get_arcbuf(dev);
 631	else {
 632		txbuf = -1;
 633	}
 634	if (txbuf != -1) {
 
 635		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
 636		    !proto->ack_tx) {
 637			/* done right away and we don't want to acknowledge
 638			   the package later - forget about it now */
 
 639			dev->stats.tx_bytes += skb->len;
 640			freeskb = 1;
 641		} else {
 642			/* do it the 'split' way */
 643			lp->outgoing.proto = proto;
 644			lp->outgoing.skb = skb;
 645			lp->outgoing.pkt = pkt;
 646
 647			freeskb = 0;
 648
 649			if (proto->continue_tx &&
 650			    proto->continue_tx(dev, txbuf)) {
 651			  BUGMSG(D_NORMAL,
 652				 "bug! continue_tx finished the first time! "
 653				 "(proto='%c')\n", proto->suffix);
 654			}
 655		}
 656		retval = NETDEV_TX_OK;
 657		lp->next_tx = txbuf;
 658	} else {
 659		retval = NETDEV_TX_BUSY;
 660		freeskb = 0;
 661	}
 662
 663	BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__func__,ASTATUS());
 
 664	/* make sure we didn't ignore a TX IRQ while we were in here */
 665	AINTMASK(0);
 666
 667	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__func__);
 668	lp->intmask |= TXFREEflag|EXCNAKflag;
 669	AINTMASK(lp->intmask);
 670	BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__func__,ASTATUS());
 
 
 
 671
 672	spin_unlock_irqrestore(&lp->lock, flags);
 673	if (freeskb) {
 674		dev_kfree_skb(skb);
 675	}
 676	return retval;		/* no need to try again */
 677}
 
 678
 679
 680/*
 681 * Actually start transmitting a packet that was loaded into a buffer
 682 * by prepare_tx.  This should _only_ be called by the interrupt handler.
 683 */
 684static int go_tx(struct net_device *dev)
 685{
 686	struct arcnet_local *lp = netdev_priv(dev);
 687
 688	BUGMSG(D_DURING, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n",
 689	       ASTATUS(), lp->intmask, lp->next_tx, lp->cur_tx);
 690
 691	if (lp->cur_tx != -1 || lp->next_tx == -1)
 692		return 0;
 693
 694	BUGLVL(D_TX) arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 
 695
 696	lp->cur_tx = lp->next_tx;
 697	lp->next_tx = -1;
 698
 699	/* start sending */
 700	ACOMMAND(TXcmd | (lp->cur_tx << 3));
 701
 702	dev->stats.tx_packets++;
 703	lp->lasttrans_dest = lp->lastload_dest;
 704	lp->lastload_dest = 0;
 705	lp->excnak_pending = 0;
 706	lp->intmask |= TXFREEflag|EXCNAKflag;
 707
 708	return 1;
 709}
 710
 711
 712/* Called by the kernel when transmit times out */
 713void arcnet_timeout(struct net_device *dev)
 714{
 715	unsigned long flags;
 716	struct arcnet_local *lp = netdev_priv(dev);
 717	int status = ASTATUS();
 718	char *msg;
 719
 720	spin_lock_irqsave(&lp->lock, flags);
 721	if (status & TXFREEflag) {	/* transmit _DID_ finish */
 722		msg = " - missed IRQ?";
 723	} else {
 724		msg = "";
 725		dev->stats.tx_aborted_errors++;
 726		lp->timed_out = 1;
 727		ACOMMAND(NOTXcmd | (lp->cur_tx << 3));
 728	}
 729	dev->stats.tx_errors++;
 730
 731	/* make sure we didn't miss a TX or a EXC NAK IRQ */
 732	AINTMASK(0);
 733	lp->intmask |= TXFREEflag|EXCNAKflag;
 734	AINTMASK(lp->intmask);
 735	
 736	spin_unlock_irqrestore(&lp->lock, flags);
 737
 738	if (time_after(jiffies, lp->last_timeout + 10*HZ)) {
 739		BUGMSG(D_EXTRA, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
 740		       msg, status, lp->intmask, lp->lasttrans_dest);
 741		lp->last_timeout = jiffies;
 742	}
 743
 744	if (lp->cur_tx == -1)
 745		netif_wake_queue(dev);
 746}
 
 747
 748
 749/*
 750 * The typical workload of the driver: Handle the network interface
 751 * interrupts. Establish which device needs attention, and call the correct
 752 * chipset interrupt handler.
 753 */
 754irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 755{
 756	struct net_device *dev = dev_id;
 757	struct arcnet_local *lp;
 758	int recbuf, status, diagstatus, didsomething, boguscount;
 
 759	int retval = IRQ_NONE;
 760
 761	BUGMSG(D_DURING, "\n");
 762
 763	BUGMSG(D_DURING, "in arcnet_interrupt\n");
 764
 765	lp = netdev_priv(dev);
 766	BUG_ON(!lp);
 767		
 768	spin_lock(&lp->lock);
 769
 770	/*
 771	 * RESET flag was enabled - if device is not running, we must clear it right
 772	 * away (but nothing else).
 
 773	 */
 774	if (!netif_running(dev)) {
 775		if (ASTATUS() & RESETflag)
 776			ACOMMAND(CFLAGScmd | RESETclear);
 777		AINTMASK(0);
 778		spin_unlock(&lp->lock);
 779		return IRQ_HANDLED;
 780	}
 781
 782	BUGMSG(D_DURING, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n",
 783	       ASTATUS(), lp->intmask);
 784
 785	boguscount = 5;
 786	do {
 787		status = ASTATUS();
 788                diagstatus = (status >> 8) & 0xFF;
 789
 790		BUGMSG(D_DEBUG, "%s: %d: %s: status=%x\n",
 791			__FILE__,__LINE__,__func__,status);
 792		didsomething = 0;
 793
 794		/*
 795		 * RESET flag was enabled - card is resetting and if RX is
 796		 * disabled, it's NOT because we just got a packet.
 797		 * 
 798		 * The card is in an undefined state.  Clear it out and start over.
 
 799		 */
 800		if (status & RESETflag) {
 801			BUGMSG(D_NORMAL, "spurious reset (status=%Xh)\n", status);
 
 802			arcnet_close(dev);
 803			arcnet_open(dev);
 804
 805			/* get out of the interrupt handler! */
 806			break;
 807		}
 808		/* 
 809		 * RX is inhibited - we must have received something. Prepare to
 810		 * receive into the next buffer.
 811		 * 
 812		 * We don't actually copy the received packet from the card until
 813		 * after the transmit handler runs (and possibly launches the next
 814		 * tx); this should improve latency slightly if we get both types
 815		 * of interrupts at once. 
 816		 */
 817		recbuf = -1;
 818		if (status & lp->intmask & NORXflag) {
 819			recbuf = lp->cur_rx;
 820			BUGMSG(D_DURING, "Buffer #%d: receive irq (status=%Xh)\n",
 821			       recbuf, status);
 822
 823			lp->cur_rx = get_arcbuf(dev);
 824			if (lp->cur_rx != -1) {
 825				BUGMSG(D_DURING, "enabling receive to buffer #%d\n",
 826				       lp->cur_rx);
 827				ACOMMAND(RXcmd | (lp->cur_rx << 3) | RXbcasts);
 828			}
 829			didsomething++;
 830		}
 831
 832		if((diagstatus & EXCNAKflag)) {
 833			BUGMSG(D_DURING, "EXCNAK IRQ (diagstat=%Xh)\n",
 834			       diagstatus);
 835
 836                        ACOMMAND(NOTXcmd);      /* disable transmit */
 837                        lp->excnak_pending = 1;
 838
 839                        ACOMMAND(EXCNAKclear);
 840			lp->intmask &= ~(EXCNAKflag);
 841                        didsomething++;
 842                }
 843
 844
 845		/* a transmit finished, and we're interested in it. */
 846		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
 847			lp->intmask &= ~(TXFREEflag|EXCNAKflag);
 
 
 
 
 
 
 
 
 848
 849			BUGMSG(D_DURING, "TX IRQ (stat=%Xh)\n", status);
 
 850
 851			if (lp->cur_tx != -1 && !lp->timed_out) {
 852				if(!(status & TXACKflag)) {
 853					if (lp->lasttrans_dest != 0) {
 854						BUGMSG(D_EXTRA,
 855						       "transmit was not acknowledged! "
 856						       "(status=%Xh, dest=%02Xh)\n",
 857						       status, lp->lasttrans_dest);
 858						dev->stats.tx_errors++;
 859						dev->stats.tx_carrier_errors++;
 860					} else {
 861						BUGMSG(D_DURING,
 862						       "broadcast was not acknowledged; that's normal "
 863						       "(status=%Xh, dest=%02Xh)\n",
 864						       status, lp->lasttrans_dest);
 865					}
 866				}
 867
 868				if (lp->outgoing.proto &&
 869				    lp->outgoing.proto->ack_tx) {
 870				  int ackstatus;
 871				  if(status & TXACKflag)
 872                                    ackstatus=2;
 873                                  else if(lp->excnak_pending)
 874                                    ackstatus=1;
 875                                  else
 876                                    ackstatus=0;
 877
 878                                  lp->outgoing.proto
 879                                    ->ack_tx(dev, ackstatus);
 880				}
 
 
 881			}
 882			if (lp->cur_tx != -1)
 883				release_arcbuf(dev, lp->cur_tx);
 884
 885			lp->cur_tx = -1;
 886			lp->timed_out = 0;
 887			didsomething++;
 888
 889			/* send another packet if there is one */
 890			go_tx(dev);
 891
 892			/* continue a split packet, if any */
 893			if (lp->outgoing.proto && lp->outgoing.proto->continue_tx) {
 
 894				int txbuf = get_arcbuf(dev);
 
 895				if (txbuf != -1) {
 896					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
 897						/* that was the last segment */
 898						dev->stats.tx_bytes += lp->outgoing.skb->len;
 899						if(!lp->outgoing.proto->ack_tx)
 900						  {
 901						    dev_kfree_skb_irq(lp->outgoing.skb);
 902						    lp->outgoing.proto = NULL;
 903						  }
 904					}
 905					lp->next_tx = txbuf;
 906				}
 907			}
 908			/* inform upper layers of idleness, if necessary */
 909			if (lp->cur_tx == -1)
 910				netif_wake_queue(dev);
 911		}
 912		/* now process the received packet, if any */
 913		if (recbuf != -1) {
 914			BUGLVL(D_RX) arcnet_dump_packet(dev, recbuf, "rx irq", 0);
 
 915
 916			arcnet_rx(dev, recbuf);
 917			release_arcbuf(dev, recbuf);
 918
 919			didsomething++;
 920		}
 921		if (status & lp->intmask & RECONflag) {
 922			ACOMMAND(CFLAGScmd | CONFIGclear);
 923			dev->stats.tx_carrier_errors++;
 924
 925			BUGMSG(D_RECON, "Network reconfiguration detected (status=%Xh)\n",
 926			       status);
 
 
 
 
 
 
 
 927			/* MYRECON bit is at bit 7 of diagstatus */
 928			if(diagstatus & 0x80)
 929				BUGMSG(D_RECON,"Put out that recon myself\n");
 930
 931			/* is the RECON info empty or old? */
 932			if (!lp->first_recon || !lp->last_recon ||
 933			    time_after(jiffies, lp->last_recon + HZ * 10)) {
 934				if (lp->network_down)
 935					BUGMSG(D_NORMAL, "reconfiguration detected: cabling restored?\n");
 936				lp->first_recon = lp->last_recon = jiffies;
 937				lp->num_recons = lp->network_down = 0;
 938
 939				BUGMSG(D_DURING, "recon: clearing counters.\n");
 940			} else {	/* add to current RECON counter */
 941				lp->last_recon = jiffies;
 942				lp->num_recons++;
 943
 944				BUGMSG(D_DURING, "recon: counter=%d, time=%lds, net=%d\n",
 945				       lp->num_recons,
 946				 (lp->last_recon - lp->first_recon) / HZ,
 947				       lp->network_down);
 948
 949				/* if network is marked up;
 950				 * and first_recon and last_recon are 60+ apart;
 951				 * and the average no. of recons counted is
 952				 *    > RECON_THRESHOLD/min;
 953				 * then print a warning message.
 954				 */
 955				if (!lp->network_down &&
 956				    (lp->last_recon - lp->first_recon) <= HZ * 60 &&
 957				    lp->num_recons >= RECON_THRESHOLD) {
 958					lp->network_down = 1;
 959					BUGMSG(D_NORMAL, "many reconfigurations detected: cabling problem?\n");
 960				} else if (!lp->network_down &&
 961					   lp->last_recon - lp->first_recon > HZ * 60) {
 962					/* reset counters if we've gone for over a minute. */
 
 
 963					lp->first_recon = lp->last_recon;
 964					lp->num_recons = 1;
 965				}
 966			}
 967		} else if (lp->network_down &&
 968				time_after(jiffies, lp->last_recon + HZ * 10)) {
 969			if (lp->network_down)
 970				BUGMSG(D_NORMAL, "cabling restored?\n");
 971			lp->first_recon = lp->last_recon = 0;
 972			lp->num_recons = lp->network_down = 0;
 973
 974			BUGMSG(D_DURING, "not recon: clearing counters anyway.\n");
 
 975		}
 976
 977		if(didsomething) {
 978			retval |= IRQ_HANDLED;
 979		}
 980	}
 981	while (--boguscount && didsomething);
 982
 983	BUGMSG(D_DURING, "arcnet_interrupt complete (status=%Xh, count=%d)\n",
 984	       ASTATUS(), boguscount);
 985	BUGMSG(D_DURING, "\n");
 986
 
 
 
 987
 988	AINTMASK(0);
 989	udelay(1);
 990	AINTMASK(lp->intmask);
 991	
 992	spin_unlock(&lp->lock);
 993	return retval;
 994}
 
 995
 996
 997/*
 998 * This is a generic packet receiver that calls arcnet??_rx depending on the
 999 * protocol ID found.
1000 */
1001static void arcnet_rx(struct net_device *dev, int bufnum)
1002{
1003	struct arcnet_local *lp = netdev_priv(dev);
1004	struct archdr pkt;
1005	struct arc_rfc1201 *soft;
1006	int length, ofs;
1007
1008	soft = &pkt.soft.rfc1201;
1009
1010	lp->hw.copy_from_card(dev, bufnum, 0, &pkt, sizeof(ARC_HDR_SIZE));
1011	if (pkt.hard.offset[0]) {
1012		ofs = pkt.hard.offset[0];
1013		length = 256 - ofs;
1014	} else {
1015		ofs = pkt.hard.offset[1];
1016		length = 512 - ofs;
1017	}
1018
1019	/* get the full header, if possible */
1020	if (sizeof(pkt.soft) <= length)
1021		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft));
1022	else {
1023		memset(&pkt.soft, 0, sizeof(pkt.soft));
1024		lp->hw.copy_from_card(dev, bufnum, ofs, soft, length);
1025	}
1026
1027	BUGMSG(D_DURING, "Buffer #%d: received packet from %02Xh to %02Xh "
1028	       "(%d+4 bytes)\n",
1029	       bufnum, pkt.hard.source, pkt.hard.dest, length);
1030
1031	dev->stats.rx_packets++;
1032	dev->stats.rx_bytes += length + ARC_HDR_SIZE;
1033
1034	/* call the right receiver for the protocol */
1035	if (arc_proto_map[soft->proto]->is_ip) {
1036		BUGLVL(D_PROTO) {
1037			struct ArcProto
1038			*oldp = arc_proto_map[lp->default_proto[pkt.hard.source]],
1039			*newp = arc_proto_map[soft->proto];
1040
1041			if (oldp != newp) {
1042				BUGMSG(D_PROTO,
1043				       "got protocol %02Xh; encap for host %02Xh is now '%c'"
1044				       " (was '%c')\n", soft->proto, pkt.hard.source,
1045				       newp->suffix, oldp->suffix);
1046			}
1047		}
1048
1049		/* broadcasts will always be done with the last-used encap. */
1050		lp->default_proto[0] = soft->proto;
1051
1052		/* in striking contrast, the following isn't a hack. */
1053		lp->default_proto[pkt.hard.source] = soft->proto;
1054	}
1055	/* call the protocol-specific receiver. */
1056	arc_proto_map[soft->proto]->rx(dev, bufnum, &pkt, length);
1057}
1058
1059
1060static void null_rx(struct net_device *dev, int bufnum,
1061		    struct archdr *pkthdr, int length)
1062{
1063	BUGMSG(D_PROTO,
1064	"rx: don't know how to deal with proto %02Xh from host %02Xh.\n",
1065	       pkthdr->soft.rfc1201.proto, pkthdr->hard.source);
1066}
1067
1068
1069static int null_build_header(struct sk_buff *skb, struct net_device *dev,
1070			     unsigned short type, uint8_t daddr)
1071{
1072	struct arcnet_local *lp = netdev_priv(dev);
1073
1074	BUGMSG(D_PROTO,
1075	       "tx: can't build header for encap %02Xh; load a protocol driver.\n",
1076	       lp->default_proto[daddr]);
1077
1078	/* always fails */
1079	return 0;
1080}
1081
1082
1083/* the "do nothing" prepare_tx function warns that there's nothing to do. */
1084static int null_prepare_tx(struct net_device *dev, struct archdr *pkt,
1085			   int length, int bufnum)
1086{
1087	struct arcnet_local *lp = netdev_priv(dev);
1088	struct arc_hardware newpkt;
1089
1090	BUGMSG(D_PROTO, "tx: no encap for this host; load a protocol driver.\n");
1091
1092	/* send a packet to myself -- will never get received, of course */
1093	newpkt.source = newpkt.dest = dev->dev_addr[0];
1094
1095	/* only one byte of actual data (and it's random) */
1096	newpkt.offset[0] = 0xFF;
1097
1098	lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE);
1099
1100	return 1;		/* done */
1101}