/* * Linux ARCnet driver - device-independent routines * * Written 1997 by David Woodhouse. * Written 1994-1999 by Avery Pennarun. * Written 1999-2000 by Martin Mares <mj@ucw.cz>. * Derived from skeleton.c by Donald Becker. * * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com) * for sponsoring the further development of this driver. * * ********************** * * The original copyright was as follows: * * skeleton.c Written 1993 by Donald Becker. * Copyright 1993 United States Government as represented by the * Director, National Security Agency. This software may only be used * and distributed according to the terms of the GNU General Public License as * modified by SRC, incorporated herein by reference. * * ********************** * * The change log is now in a file called ChangeLog in this directory. * * Sources: * - Crynwr arcnet.com/arcether.com packet drivers. * - arcnet.c v0.00 dated 1/1/94 and apparently by * Donald Becker - it didn't work :) * - skeleton.c v0.05 dated 11/16/93 by Donald Becker * (from Linux Kernel 1.1.45) * - RFC's 1201 and 1051 - re: TCP/IP over ARCnet * - The official ARCnet COM9026 data sheets (!) thanks to * Ken Cornetet <kcornete@nyx10.cs.du.edu> * - The official ARCnet COM20020 data sheets. * - Information on some more obscure ARCnet controller chips, thanks * to the nice people at SMSC. * - net/inet/eth.c (from kernel 1.1.50) for header-building info. * - Alternate Linux ARCnet source by V.Shergin <vsher@sao.stavropol.su> * - Textual information and more alternate source from Joachim Koenig * <jojo@repas.de> */ #define VERSION "arcnet: v3.93 BETA 2000/04/29 - by Avery Pennarun et al.\n" #include <linux/module.h> #include <linux/config.h> #include <linux/types.h> #include <linux/delay.h> #include <linux/netdevice.h> #include <linux/if_arp.h> #include <net/arp.h> #include <linux/init.h> #include <linux/arcdevice.h> /* "do nothing" functions for protocol drivers */ static void null_rx(struct net_device *dev, int bufnum, struct archdr *pkthdr, int length); static int null_build_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, uint8_t daddr); static int null_prepare_tx(struct net_device *dev, struct archdr *pkt, int length, int bufnum); /* * one ArcProto per possible proto ID. None of the elements of * arc_proto_map are allowed to be NULL; they will get set to * arc_proto_default instead. It also must not be NULL; if you would like * to set it to NULL, set it to &arc_proto_null instead. */ struct ArcProto *arc_proto_map[256], *arc_proto_default, *arc_bcast_proto, *arc_raw_proto; struct ArcProto arc_proto_null = { .suffix = '?', .mtu = XMTU, .is_ip = 0, .rx = null_rx, .build_header = null_build_header, .prepare_tx = null_prepare_tx, .continue_tx = NULL, .ack_tx = NULL }; /* Exported function prototypes */ int arcnet_debug = ARCNET_DEBUG; EXPORT_SYMBOL(arc_proto_map); EXPORT_SYMBOL(arc_proto_default); EXPORT_SYMBOL(arc_bcast_proto); EXPORT_SYMBOL(arc_raw_proto); EXPORT_SYMBOL(arc_proto_null); EXPORT_SYMBOL(arcnet_unregister_proto); EXPORT_SYMBOL(arcnet_debug); EXPORT_SYMBOL(alloc_arcdev); EXPORT_SYMBOL(arcnet_interrupt); /* Internal function prototypes */ static int arcnet_open(struct net_device *dev); static int arcnet_close(struct net_device *dev); static int arcnet_send_packet(struct sk_buff *skb, struct net_device *dev); static void arcnet_timeout(struct net_device *dev); static int arcnet_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, void *daddr, void *saddr, unsigned len); static int arcnet_rebuild_header(struct sk_buff *skb); static struct net_device_stats *arcnet_get_stats(struct net_device *dev); static int go_tx(struct net_device *dev); static int debug = ARCNET_DEBUG; module_param(debug, int, 0); MODULE_LICENSE("GPL"); static int __init arcnet_init(void) { int count; arcnet_debug = debug; printk(VERSION); #ifdef ALPHA_WARNING BUGLVL(D_EXTRA) { printk("arcnet: ***\n" "arcnet: * Read arcnet.txt for important release notes!\n" "arcnet: *\n" "arcnet: * This is an ALPHA version! (Last stable release: v3.02) E-mail\n" "arcnet: * me if you have any questions, comments, or bug reports.\n" "arcnet: ***\n"); } #endif /* initialize the protocol map */ arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null; for (count = 0; count < 256; count++) arc_proto_map[count] = arc_proto_default; BUGLVL(D_DURING) printk("arcnet: struct sizes: %Zd %Zd %Zd %Zd %Zd\n", sizeof(struct arc_hardware), sizeof(struct arc_rfc1201), sizeof(struct arc_rfc1051), sizeof(struct arc_eth_encap), sizeof(struct archdr)); return 0; } static void __exit arcnet_exit(void) { } module_init(arcnet_init); module_exit(arcnet_exit); /* * Dump the contents of an sk_buff */ #if ARCNET_DEBUG_MAX & D_SKB void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc) { int i; printk(KERN_DEBUG "%6s: skb dump (%s) follows:", dev->name, desc); for (i = 0; i < skb->len; i++) { if (i % 16 == 0) printk("\n" KERN_DEBUG "[%04X] ", i); printk("%02X ", ((u_char *) skb->data)[i]); } printk("\n"); } EXPORT_SYMBOL(arcnet_dump_skb); #endif /* * Dump the contents of an ARCnet buffer */ #if (ARCNET_DEBUG_MAX & (D_RX | D_TX)) void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc, int take_arcnet_lock) { struct arcnet_local *lp = dev->priv; int i, length; unsigned long flags = 0; static uint8_t buf[512]; /* hw.copy_from_card expects IRQ context so take the IRQ lock to keep it single threaded */ if(take_arcnet_lock) spin_lock_irqsave(&lp->lock, flags); lp->hw.copy_from_card(dev, bufnum, 0, buf, 512); if(take_arcnet_lock) spin_unlock_irqrestore(&lp->lock, flags); /* if the offset[0] byte is nonzero, this is a 256-byte packet */ length = (buf[2] ? 256 : 512); printk(KERN_DEBUG "%6s: packet dump (%s) follows:", dev->name, desc); for (i = 0; i < length; i++) { if (i % 16 == 0) printk("\n" KERN_DEBUG "[%04X] ", i); printk("%02X ", buf[i]); } printk("\n"); } EXPORT_SYMBOL(arcnet_dump_packet); #endif /* * Unregister a protocol driver from the arc_proto_map. Protocol drivers * are responsible for registering themselves, but the unregister routine * is pretty generic so we'll do it here. */ void arcnet_unregister_proto(struct ArcProto *proto) { int count; if (arc_proto_default == proto) arc_proto_default = &arc_proto_null; if (arc_bcast_proto == proto) arc_bcast_proto = arc_proto_default; if (arc_raw_proto == proto) arc_raw_proto = arc_proto_default; for (count = 0; count < 256; count++) { if (arc_proto_map[count] == proto) arc_proto_map[count] = arc_proto_default; } } /* * Add a buffer to the queue. Only the interrupt handler is allowed to do * this, unless interrupts are disabled. * * Note: we don't check for a full queue, since there aren't enough buffers * to more than fill it. */ static void release_arcbuf(struct net_device *dev, int bufnum) { struct arcnet_local *lp = dev->priv; int i; lp->buf_queue[lp->first_free_buf++] = bufnum; lp->first_free_buf %= 5; BUGLVL(D_DURING) { BUGMSG(D_DURING, "release_arcbuf: freed #%d; buffer queue is now: ", bufnum); for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5) BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]); BUGMSG2(D_DURING, "\n"); } } /* * Get a buffer from the queue. If this returns -1, there are no buffers * available. */ static int get_arcbuf(struct net_device *dev) { struct arcnet_local *lp = dev->priv; int buf = -1, i; if (!atomic_dec_and_test(&lp->buf_lock)) { /* already in this function */ BUGMSG(D_NORMAL, "get_arcbuf: overlap (%d)!\n", lp->buf_lock.counter); } else { /* we can continue */ if (lp->next_buf >= 5) lp->next_buf -= 5; if (lp->next_buf == lp->first_free_buf) BUGMSG(D_NORMAL, "get_arcbuf: BUG: no buffers are available??\n"); else { buf = lp->buf_queue[lp->next_buf++]; lp->next_buf %= 5; } } BUGLVL(D_DURING) { BUGMSG(D_DURING, "get_arcbuf: got #%d; buffer queue is now: ", buf); for (i = lp->next_buf; i != lp->first_free_buf; i = (i+1) % 5) BUGMSG2(D_DURING, "#%d ", lp->buf_queue[i]); BUGMSG2(D_DURING, "\n"); } atomic_inc(&lp->buf_lock); return buf; } static int choose_mtu(void) { int count, mtu = 65535; /* choose the smallest MTU of all available encaps */ for (count = 0; count < 256; count++) { if (arc_proto_map[count] != &arc_proto_null && arc_proto_map[count]->mtu < mtu) { mtu = arc_proto_map[count]->mtu; } } return mtu == 65535 ? XMTU : mtu; } /* Setup a struct device for ARCnet. */ static void arcdev_setup(struct net_device *dev) { dev->type = ARPHRD_ARCNET; dev->hard_header_len = sizeof(struct archdr); dev->mtu = choose_mtu(); dev->addr_len = ARCNET_ALEN; dev->tx_queue_len = 100; dev->broadcast[0] = 0x00; /* for us, broadcasts are address 0 */ dev->watchdog_timeo = TX_TIMEOUT; /* New-style flags. */ dev->flags = IFF_BROADCAST; /* * Put in this stuff here, so we don't have to export the symbols to * the chipset drivers. */ dev->open = arcnet_open; dev->stop = arcnet_close; dev->hard_start_xmit = arcnet_send_packet; dev->tx_timeout = arcnet_timeout; dev->get_stats = arcnet_get_stats; dev->hard_header = arcnet_header; dev->rebuild_header = arcnet_rebuild_header; } struct net_device *alloc_arcdev(char *name) { struct net_device *dev; dev = alloc_netdev(sizeof(struct arcnet_local), name && *name ? name : "arc%d", arcdev_setup); if(dev) { struct arcnet_local *lp = (struct arcnet_local *) dev->priv; spin_lock_init(&lp->lock); } return dev; } /* * Open/initialize the board. This is called sometime after booting when * the 'ifconfig' program is run. * * This routine should set everything up anew at each open, even registers * that "should" only need to be set once at boot, so that there is * non-reboot way to recover if something goes wrong. */ static int arcnet_open(struct net_device *dev) { struct arcnet_local *lp = dev->priv; int count, newmtu, error; BUGMSG(D_INIT,"opened."); if (!try_module_get(lp->hw.owner)) return -ENODEV; BUGLVL(D_PROTO) { int count; BUGMSG(D_PROTO, "protocol map (default is '%c'): ", arc_proto_default->suffix); for (count = 0; count < 256; count++) BUGMSG2(D_PROTO, "%c", arc_proto_map[count]->suffix); BUGMSG2(D_PROTO, "\n"); } BUGMSG(D_INIT, "arcnet_open: resetting card.\n"); /* try to put the card in a defined state - if it fails the first * time, actually reset it. */ error = -ENODEV; if (ARCRESET(0) && ARCRESET(1)) goto out_module_put; newmtu = choose_mtu(); if (newmtu < dev->mtu) dev->mtu = newmtu; BUGMSG(D_INIT, "arcnet_open: mtu: %d.\n", dev->mtu); /* autodetect the encapsulation for each host. */ memset(lp->default_proto, 0, sizeof(lp->default_proto)); /* the broadcast address is special - use the 'bcast' protocol */ for (count = 0; count < 256; count++) { if (arc_proto_map[count] == arc_bcast_proto) { lp->default_proto[0] = count; break; } } /* initialize buffers */ atomic_set(&lp->buf_lock, 1); lp->next_buf = lp->first_free_buf = 0; release_arcbuf(dev, 0); release_arcbuf(dev, 1); release_arcbuf(dev, 2); release_arcbuf(dev, 3); lp->cur_tx = lp->next_tx = -1; lp->cur_rx = -1; lp->rfc1201.sequence = 1; /* bring up the hardware driver */ if (lp->hw.open) lp->hw.open(dev); if (dev->dev_addr[0] == 0) BUGMSG(D_NORMAL, "WARNING! Station address 00 is reserved " "for broadcasts!\n"); else if (dev->dev_addr[0] == 255) BUGMSG(D_NORMAL, "WARNING! Station address FF may confuse " "DOS networking programs!\n"); BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); if (ASTATUS() & RESETflag) { BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); ACOMMAND(CFLAGScmd | RESETclear); } BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); /* make sure we're ready to receive IRQ's. */ AINTMASK(0); udelay(1); /* give it time to set the mask before * we reset it again. (may not even be * necessary) */ BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); lp->intmask = NORXflag | RECONflag; AINTMASK(lp->intmask); BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); netif_start_queue(dev); return 0; out_module_put: module_put(lp->hw.owner); return error; } /* The inverse routine to arcnet_open - shuts down the card. */ static int arcnet_close(struct net_device *dev) { struct arcnet_local *lp = dev->priv; netif_stop_queue(dev); /* flush TX and disable RX */ AINTMASK(0); ACOMMAND(NOTXcmd); /* stop transmit */ ACOMMAND(NORXcmd); /* disable receive */ mdelay(1); /* shut down the card */ lp->hw.close(dev); module_put(lp->hw.owner); return 0; } static int arcnet_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, void *daddr, void *saddr, unsigned len) { struct arcnet_local *lp = dev->priv; uint8_t _daddr, proto_num; struct ArcProto *proto; BUGMSG(D_DURING, "create header from %d to %d; protocol %d (%Xh); size %u.\n", saddr ? *(uint8_t *) saddr : -1, daddr ? *(uint8_t *) daddr : -1, type, type, len); if (skb->len!=0 && len != skb->len) BUGMSG(D_NORMAL, "arcnet_header: Yikes! skb->len(%d) != len(%d)!\n", skb->len, len); /* Type is host order - ? */ if(type == ETH_P_ARCNET) { proto = arc_raw_proto; BUGMSG(D_DEBUG, "arc_raw_proto used. proto='%c'\n",proto->suffix); _daddr = daddr ? *(uint8_t *) daddr : 0; } else if (!daddr) { /* * if the dest addr isn't provided, we can't choose an encapsulation! * Store the packet type (eg. ETH_P_IP) for now, and we'll push on a * real header when we do rebuild_header. */ *(uint16_t *) skb_push(skb, 2) = type; if (skb->nh.raw - skb->mac.raw != 2) BUGMSG(D_NORMAL, "arcnet_header: Yikes! diff (%d) is not 2!\n", (int)(skb->nh.raw - skb->mac.raw)); return -2; /* return error -- can't transmit yet! */ } else { /* otherwise, we can just add the header as usual. */ _daddr = *(uint8_t *) daddr; proto_num = lp->default_proto[_daddr]; proto = arc_proto_map[proto_num]; BUGMSG(D_DURING, "building header for %02Xh using protocol '%c'\n", proto_num, proto->suffix); if (proto == &arc_proto_null && arc_bcast_proto != proto) { BUGMSG(D_DURING, "actually, let's use '%c' instead.\n", arc_bcast_proto->suffix); proto = arc_bcast_proto; } } return proto->build_header(skb, dev, type, _daddr); } /* * Rebuild the ARCnet hard header. This is called after an ARP (or in the * future other address resolution) has completed on this sk_buff. We now * let ARP fill in the destination field. */ static int arcnet_rebuild_header(struct sk_buff *skb) { struct net_device *dev = skb->dev; struct arcnet_local *lp = dev->priv; int status = 0; /* default is failure */ unsigned short type; uint8_t daddr=0; struct ArcProto *proto; if (skb->nh.raw - skb->mac.raw != 2) { BUGMSG(D_NORMAL, "rebuild_header: shouldn't be here! (hdrsize=%d)\n", (int)(skb->nh.raw - skb->mac.raw)); return 0; } type = *(uint16_t *) skb_pull(skb, 2); BUGMSG(D_DURING, "rebuild header for protocol %Xh\n", type); if (type == ETH_P_IP) { #ifdef CONFIG_INET BUGMSG(D_DURING, "rebuild header for ethernet protocol %Xh\n", type); status = arp_find(&daddr, skb) ? 1 : 0; BUGMSG(D_DURING, " rebuilt: dest is %d; protocol %Xh\n", daddr, type); #endif } else { BUGMSG(D_NORMAL, "I don't understand ethernet protocol %Xh addresses!\n", type); lp->stats.tx_errors++; lp->stats.tx_aborted_errors++; } /* if we couldn't resolve the address... give up. */ if (!status) return 0; /* add the _real_ header this time! */ proto = arc_proto_map[lp->default_proto[daddr]]; proto->build_header(skb, dev, type, daddr); return 1; /* success */ } /* Called by the kernel in order to transmit a packet. */ static int arcnet_send_packet(struct sk_buff *skb, struct net_device *dev) { struct arcnet_local *lp = dev->priv; struct archdr *pkt; struct arc_rfc1201 *soft; struct ArcProto *proto; int txbuf; unsigned long flags; int freeskb, retval; BUGMSG(D_DURING, "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n", ASTATUS(), lp->cur_tx, lp->next_tx, skb->len,skb->protocol); pkt = (struct archdr *) skb->data; soft = &pkt->soft.rfc1201; proto = arc_proto_map[soft->proto]; BUGMSG(D_SKB_SIZE, "skb: transmitting %d bytes to %02X\n", skb->len, pkt->hard.dest); BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "tx"); /* fits in one packet? */ if (skb->len - ARC_HDR_SIZE > XMTU && !proto->continue_tx) { BUGMSG(D_NORMAL, "fixme: packet too large: compensating badly!\n"); dev_kfree_skb(skb); return NETDEV_TX_OK; /* don't try again */ } /* We're busy transmitting a packet... */ netif_stop_queue(dev); spin_lock_irqsave(&lp->lock, flags); AINTMASK(0); if(lp->next_tx == -1) txbuf = get_arcbuf(dev); else { txbuf = -1; } if (txbuf != -1) { if (proto->prepare_tx(dev, pkt, skb->len, txbuf) && !proto->ack_tx) { /* done right away and we don't want to acknowledge the package later - forget about it now */ lp->stats.tx_bytes += skb->len; freeskb = 1; } else { /* do it the 'split' way */ lp->outgoing.proto = proto; lp->outgoing.skb = skb; lp->outgoing.pkt = pkt; freeskb = 0; if (proto->continue_tx && proto->continue_tx(dev, txbuf)) { BUGMSG(D_NORMAL, "bug! continue_tx finished the first time! " "(proto='%c')\n", proto->suffix); } } retval = NETDEV_TX_OK; dev->trans_start = jiffies; lp->next_tx = txbuf; } else { retval = NETDEV_TX_BUSY; freeskb = 0; } BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS()); /* make sure we didn't ignore a TX IRQ while we were in here */ AINTMASK(0); BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__); lp->intmask |= TXFREEflag|EXCNAKflag; AINTMASK(lp->intmask); BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS()); spin_unlock_irqrestore(&lp->lock, flags); if (freeskb) { dev_kfree_skb(skb); } return retval; /* no need to try again */ } /* * Actually start transmitting a packet that was loaded into a buffer * by prepare_tx. This should _only_ be called by the interrupt handler. */ static int go_tx(struct net_device *dev) { struct arcnet_local *lp = dev->priv; BUGMSG(D_DURING, "go_tx: status=%Xh, intmask=%Xh, next_tx=%d, cur_tx=%d\n", ASTATUS(), lp->intmask, lp->next_tx, lp->cur_tx); if (lp->cur_tx != -1 || lp->next_tx == -1) return 0; BUGLVL(D_TX) arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0); lp->cur_tx = lp->next_tx; lp->next_tx = -1; /* start sending */ ACOMMAND(TXcmd | (lp->cur_tx << 3)); lp->stats.tx_packets++; lp->lasttrans_dest = lp->lastload_dest; lp->lastload_dest = 0; lp->excnak_pending = 0; lp->intmask |= TXFREEflag|EXCNAKflag; return 1; } /* Called by the kernel when transmit times out */ static void arcnet_timeout(struct net_device *dev) { unsigned long flags; struct arcnet_local *lp = dev->priv; int status = ASTATUS(); char *msg; spin_lock_irqsave(&lp->lock, flags); if (status & TXFREEflag) { /* transmit _DID_ finish */ msg = " - missed IRQ?"; } else { msg = ""; lp->stats.tx_aborted_errors++; lp->timed_out = 1; ACOMMAND(NOTXcmd | (lp->cur_tx << 3)); } lp->stats.tx_errors++; /* make sure we didn't miss a TX or a EXC NAK IRQ */ AINTMASK(0); lp->intmask |= TXFREEflag|EXCNAKflag; AINTMASK(lp->intmask); spin_unlock_irqrestore(&lp->lock, flags); if (jiffies - lp->last_timeout > 10*HZ) { BUGMSG(D_EXTRA, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n", msg, status, lp->intmask, lp->lasttrans_dest); lp->last_timeout = jiffies; } if (lp->cur_tx == -1) netif_wake_queue(dev); } /* * The typical workload of the driver: Handle the network interface * interrupts. Establish which device needs attention, and call the correct * chipset interrupt handler. */ irqreturn_t arcnet_interrupt(int irq, void *dev_id, struct pt_regs *regs) { struct net_device *dev = dev_id; struct arcnet_local *lp; int recbuf, status, diagstatus, didsomething, boguscount; int retval = IRQ_NONE; BUGMSG(D_DURING, "\n"); BUGMSG(D_DURING, "in arcnet_interrupt\n"); lp = dev->priv; if (!lp) BUG(); spin_lock(&lp->lock); /* * RESET flag was enabled - if device is not running, we must clear it right * away (but nothing else). */ if (!netif_running(dev)) { if (ASTATUS() & RESETflag) ACOMMAND(CFLAGScmd | RESETclear); AINTMASK(0); spin_unlock(&lp->lock); return IRQ_HANDLED; } BUGMSG(D_DURING, "in arcnet_inthandler (status=%Xh, intmask=%Xh)\n", ASTATUS(), lp->intmask); boguscount = 5; do { status = ASTATUS(); diagstatus = (status >> 8) & 0xFF; BUGMSG(D_DEBUG, "%s: %d: %s: status=%x\n", __FILE__,__LINE__,__FUNCTION__,status); didsomething = 0; /* * RESET flag was enabled - card is resetting and if RX is * disabled, it's NOT because we just got a packet. * * The card is in an undefined state. Clear it out and start over. */ if (status & RESETflag) { BUGMSG(D_NORMAL, "spurious reset (status=%Xh)\n", status); arcnet_close(dev); arcnet_open(dev); /* get out of the interrupt handler! */ break; } /* * RX is inhibited - we must have received something. Prepare to * receive into the next buffer. * * We don't actually copy the received packet from the card until * after the transmit handler runs (and possibly launches the next * tx); this should improve latency slightly if we get both types * of interrupts at once. */ recbuf = -1; if (status & lp->intmask & NORXflag) { recbuf = lp->cur_rx; BUGMSG(D_DURING, "Buffer #%d: receive irq (status=%Xh)\n", recbuf, status); lp->cur_rx = get_arcbuf(dev); if (lp->cur_rx != -1) { BUGMSG(D_DURING, "enabling receive to buffer #%d\n", lp->cur_rx); ACOMMAND(RXcmd | (lp->cur_rx << 3) | RXbcasts); } didsomething++; } if((diagstatus & EXCNAKflag)) { BUGMSG(D_DURING, "EXCNAK IRQ (diagstat=%Xh)\n", diagstatus); ACOMMAND(NOTXcmd); /* disable transmit */ lp->excnak_pending = 1; ACOMMAND(EXCNAKclear); lp->intmask &= ~(EXCNAKflag); didsomething++; } /* a transmit finished, and we're interested in it. */ if ((status & lp->intmask & TXFREEflag) || lp->timed_out) { lp->intmask &= ~(TXFREEflag|EXCNAKflag); BUGMSG(D_DURING, "TX IRQ (stat=%Xh)\n", status); if (lp->cur_tx != -1 && !lp->timed_out) { if(!(status & TXACKflag)) { if (lp->lasttrans_dest != 0) { BUGMSG(D_EXTRA, "transmit was not acknowledged! " "(status=%Xh, dest=%02Xh)\n", status, lp->lasttrans_dest); lp->stats.tx_errors++; lp->stats.tx_carrier_errors++; } else { BUGMSG(D_DURING, "broadcast was not acknowledged; that's normal " "(status=%Xh, dest=%02Xh)\n", status, lp->lasttrans_dest); } } if (lp->outgoing.proto && lp->outgoing.proto->ack_tx) { int ackstatus; if(status & TXACKflag) ackstatus=2; else if(lp->excnak_pending) ackstatus=1; else ackstatus=0; lp->outgoing.proto ->ack_tx(dev, ackstatus); } } if (lp->cur_tx != -1) release_arcbuf(dev, lp->cur_tx); lp->cur_tx = -1; lp->timed_out = 0; didsomething++; /* send another packet if there is one */ go_tx(dev); /* continue a split packet, if any */ if (lp->outgoing.proto && lp->outgoing.proto->continue_tx) { int txbuf = get_arcbuf(dev); if (txbuf != -1) { if (lp->outgoing.proto->continue_tx(dev, txbuf)) { /* that was the last segment */ lp->stats.tx_bytes += lp->outgoing.skb->len; if(!lp->outgoing.proto->ack_tx) { dev_kfree_skb_irq(lp->outgoing.skb); lp->outgoing.proto = NULL; } } lp->next_tx = txbuf; } } /* inform upper layers of idleness, if necessary */ if (lp->cur_tx == -1) netif_wake_queue(dev); } /* now process the received packet, if any */ if (recbuf != -1) { BUGLVL(D_RX) arcnet_dump_packet(dev, recbuf, "rx irq", 0); arcnet_rx(dev, recbuf); release_arcbuf(dev, recbuf); didsomething++; } if (status & lp->intmask & RECONflag) { ACOMMAND(CFLAGScmd | CONFIGclear); lp->stats.tx_carrier_errors++; BUGMSG(D_RECON, "Network reconfiguration detected (status=%Xh)\n", status); /* MYRECON bit is at bit 7 of diagstatus */ if(diagstatus & 0x80) BUGMSG(D_RECON,"Put out that recon myself\n"); /* is the RECON info empty or old? */ if (!lp->first_recon || !lp->last_recon || jiffies - lp->last_recon > HZ * 10) { if (lp->network_down) BUGMSG(D_NORMAL, "reconfiguration detected: cabling restored?\n"); lp->first_recon = lp->last_recon = jiffies; lp->num_recons = lp->network_down = 0; BUGMSG(D_DURING, "recon: clearing counters.\n"); } else { /* add to current RECON counter */ lp->last_recon = jiffies; lp->num_recons++; BUGMSG(D_DURING, "recon: counter=%d, time=%lds, net=%d\n", lp->num_recons, (lp->last_recon - lp->first_recon) / HZ, lp->network_down); /* if network is marked up; * and first_recon and last_recon are 60+ apart; * and the average no. of recons counted is * > RECON_THRESHOLD/min; * then print a warning message. */ if (!lp->network_down && (lp->last_recon - lp->first_recon) <= HZ * 60 && lp->num_recons >= RECON_THRESHOLD) { lp->network_down = 1; BUGMSG(D_NORMAL, "many reconfigurations detected: cabling problem?\n"); } else if (!lp->network_down && lp->last_recon - lp->first_recon > HZ * 60) { /* reset counters if we've gone for over a minute. */ lp->first_recon = lp->last_recon; lp->num_recons = 1; } } } else if (lp->network_down && jiffies - lp->last_recon > HZ * 10) { if (lp->network_down) BUGMSG(D_NORMAL, "cabling restored?\n"); lp->first_recon = lp->last_recon = 0; lp->num_recons = lp->network_down = 0; BUGMSG(D_DURING, "not recon: clearing counters anyway.\n"); } if(didsomething) { retval |= IRQ_HANDLED; } } while (--boguscount && didsomething); BUGMSG(D_DURING, "arcnet_interrupt complete (status=%Xh, count=%d)\n", ASTATUS(), boguscount); BUGMSG(D_DURING, "\n"); AINTMASK(0); udelay(1); AINTMASK(lp->intmask); spin_unlock(&lp->lock); return retval; } /* * This is a generic packet receiver that calls arcnet??_rx depending on the * protocol ID found. */ void arcnet_rx(struct net_device *dev, int bufnum) { struct arcnet_local *lp = dev->priv; struct archdr pkt; struct arc_rfc1201 *soft; int length, ofs; soft = &pkt.soft.rfc1201; lp->hw.copy_from_card(dev, bufnum, 0, &pkt, sizeof(ARC_HDR_SIZE)); if (pkt.hard.offset[0]) { ofs = pkt.hard.offset[0]; length = 256 - ofs; } else { ofs = pkt.hard.offset[1]; length = 512 - ofs; } /* get the full header, if possible */ if (sizeof(pkt.soft) <= length) lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft)); else { memset(&pkt.soft, 0, sizeof(pkt.soft)); lp->hw.copy_from_card(dev, bufnum, ofs, soft, length); } BUGMSG(D_DURING, "Buffer #%d: received packet from %02Xh to %02Xh " "(%d+4 bytes)\n", bufnum, pkt.hard.source, pkt.hard.dest, length); lp->stats.rx_packets++; lp->stats.rx_bytes += length + ARC_HDR_SIZE; /* call the right receiver for the protocol */ if (arc_proto_map[soft->proto]->is_ip) { BUGLVL(D_PROTO) { struct ArcProto *oldp = arc_proto_map[lp->default_proto[pkt.hard.source]], *newp = arc_proto_map[soft->proto]; if (oldp != newp) { BUGMSG(D_PROTO, "got protocol %02Xh; encap for host %02Xh is now '%c'" " (was '%c')\n", soft->proto, pkt.hard.source, newp->suffix, oldp->suffix); } } /* broadcasts will always be done with the last-used encap. */ lp->default_proto[0] = soft->proto; /* in striking contrast, the following isn't a hack. */ lp->default_proto[pkt.hard.source] = soft->proto; } /* call the protocol-specific receiver. */ arc_proto_map[soft->proto]->rx(dev, bufnum, &pkt, length); } /* * Get the current statistics. This may be called with the card open or * closed. */ static struct net_device_stats *arcnet_get_stats(struct net_device *dev) { struct arcnet_local *lp = dev->priv; return &lp->stats; } static void null_rx(struct net_device *dev, int bufnum, struct archdr *pkthdr, int length) { BUGMSG(D_PROTO, "rx: don't know how to deal with proto %02Xh from host %02Xh.\n", pkthdr->soft.rfc1201.proto, pkthdr->hard.source); } static int null_build_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, uint8_t daddr) { struct arcnet_local *lp = dev->priv; BUGMSG(D_PROTO, "tx: can't build header for encap %02Xh; load a protocol driver.\n", lp->default_proto[daddr]); /* always fails */ return 0; } /* the "do nothing" prepare_tx function warns that there's nothing to do. */ static int null_prepare_tx(struct net_device *dev, struct archdr *pkt, int length, int bufnum) { struct arcnet_local *lp = dev->priv; struct arc_hardware newpkt; BUGMSG(D_PROTO, "tx: no encap for this host; load a protocol driver.\n"); /* send a packet to myself -- will never get received, of course */ newpkt.source = newpkt.dest = dev->dev_addr[0]; /* only one byte of actual data (and it's random) */ newpkt.offset[0] = 0xFF; lp->hw.copy_to_card(dev, bufnum, 0, &newpkt, ARC_HDR_SIZE); return 1; /* done */ }