Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1102 insertions, 0 deletions

diff --git a/drivers/net/arcnet/arcnet.c b/drivers/net/arcnet/arcnet.c
new file mode 100644
index 000000000000..4f9f69e22c1b
--- /dev/null
+++ b/drivers/net/arcnet/arcnet.c
@@ -0,0 +1,1102 @@
+/*
+ * 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 = 0;
+
+        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 0;       /* don't try again */
+        }
+
+        /* We're busy transmitting a packet... */
+        netif_stop_queue(dev);
+
+        spin_lock_irqsave(&lp->lock, flags);
+        AINTMASK(0);
+
+        txbuf = get_arcbuf(dev);
+        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;
+
+                        if (proto->continue_tx &&
+                            proto->continue_tx(dev, txbuf)) {
+                          BUGMSG(D_NORMAL,
+                                 "bug! continue_tx finished the first time! "
+                                 "(proto='%c')\n", proto->suffix);
+                        }
+                }
+
+                lp->next_tx = txbuf;
+        } else {
+                freeskb = 1;
+        }
+
+        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 0;               /* 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));
+
+        dev->trans_start = jiffies;
+        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);
+
+                        /* 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 */
+}