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, 965 insertions, 0 deletions

diff --git a/drivers/net/3c507.c b/drivers/net/3c507.c
new file mode 100644
index 000000000000..4db82893909c
--- /dev/null
+++ b/drivers/net/3c507.c
@@ -0,0 +1,965 @@
+/* 3c507.c: An EtherLink16 device driver for Linux. */
+/*
+	Written 1993,1994 by Donald Becker.
+
+	Copyright 1993 United States Government as represented by the
+	Director, National Security Agency.
+
+	This software may be used and distributed according to the terms
+	of the GNU General Public License, incorporated herein by reference.
+
+	The author may be reached as becker@scyld.com, or C/O
+	Scyld Computing Corporation
+	410 Severn Ave., Suite 210
+	Annapolis MD 21403
+
+
+	Thanks go to jennings@Montrouge.SMR.slb.com ( Patrick Jennings)
+	and jrs@world.std.com (Rick Sladkey) for testing and bugfixes.
+	Mark Salazar <leslie@access.digex.net> made the changes for cards with
+	only 16K packet buffers.
+
+	Things remaining to do:
+	Verify that the tx and rx buffers don't have fencepost errors.
+	Move the theory of operation and memory map documentation.
+	The statistics need to be updated correctly.
+*/
+
+#define DRV_NAME		"3c507"
+#define DRV_VERSION		"1.10a"
+#define DRV_RELDATE		"11/17/2001"
+
+static const char version[] =
+	DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " Donald Becker (becker@scyld.com)\n";
+
+/*
+  Sources:
+	This driver wouldn't have been written with the availability of the
+	Crynwr driver source code.	It provided a known-working implementation
+	that filled in the gaping holes of the Intel documentation.  Three cheers
+	for Russ Nelson.
+
+	Intel Microcommunications Databook, Vol. 1, 1990.  It provides just enough
+	info that the casual reader might think that it documents the i82586 :-<.
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/in.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/ethtool.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+
+#include <asm/dma.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+/* use 0 for production, 1 for verification, 2..7 for debug */
+#ifndef NET_DEBUG
+#define NET_DEBUG 1
+#endif
+static unsigned int net_debug = NET_DEBUG;
+#define debug net_debug
+
+
+/*
+  			Details of the i82586.
+
+   You'll really need the databook to understand the details of this part,
+   but the outline is that the i82586 has two separate processing units.
+   Both are started from a list of three configuration tables, of which only
+   the last, the System Control Block (SCB), is used after reset-time.  The SCB
+   has the following fields:
+		Status word
+		Command word
+		Tx/Command block addr.
+		Rx block addr.
+   The command word accepts the following controls for the Tx and Rx units:
+  */
+
+#define	 CUC_START	 0x0100
+#define	 CUC_RESUME	 0x0200
+#define	 CUC_SUSPEND 0x0300
+#define	 RX_START	 0x0010
+#define	 RX_RESUME	 0x0020
+#define	 RX_SUSPEND	 0x0030
+
+/* The Rx unit uses a list of frame descriptors and a list of data buffer
+   descriptors.  We use full-sized (1518 byte) data buffers, so there is
+   a one-to-one pairing of frame descriptors to buffer descriptors.
+
+   The Tx ("command") unit executes a list of commands that look like:
+		Status word		Written by the 82586 when the command is done.
+		Command word	Command in lower 3 bits, post-command action in upper 3
+		Link word		The address of the next command.
+		Parameters		(as needed).
+
+	Some definitions related to the Command Word are:
+ */
+#define CMD_EOL		0x8000			/* The last command of the list, stop. */
+#define CMD_SUSP	0x4000			/* Suspend after doing cmd. */
+#define CMD_INTR	0x2000			/* Interrupt after doing cmd. */
+
+enum commands {
+	CmdNOp = 0, CmdSASetup = 1, CmdConfigure = 2, CmdMulticastList = 3,
+	CmdTx = 4, CmdTDR = 5, CmdDump = 6, CmdDiagnose = 7};
+
+/* Information that need to be kept for each board. */
+struct net_local {
+	struct net_device_stats stats;
+	int last_restart;
+	ushort rx_head;
+	ushort rx_tail;
+	ushort tx_head;
+	ushort tx_cmd_link;
+	ushort tx_reap;
+	ushort tx_pkts_in_ring;
+	spinlock_t lock;
+	void __iomem *base;
+};
+
+/*
+  		Details of the EtherLink16 Implementation
+  The 3c507 is a generic shared-memory i82586 implementation.
+  The host can map 16K, 32K, 48K, or 64K of the 64K memory into
+  0x0[CD][08]0000, or all 64K into 0xF[02468]0000.
+  */
+
+/* Offsets from the base I/O address. */
+#define	SA_DATA		0	/* Station address data, or 3Com signature. */
+#define MISC_CTRL	6	/* Switch the SA_DATA banks, and bus config bits. */
+#define RESET_IRQ	10	/* Reset the latched IRQ line. */
+#define SIGNAL_CA	11	/* Frob the 82586 Channel Attention line. */
+#define ROM_CONFIG	13
+#define MEM_CONFIG	14
+#define IRQ_CONFIG	15
+#define EL16_IO_EXTENT 16
+
+/* The ID port is used at boot-time to locate the ethercard. */
+#define ID_PORT		0x100
+
+/* Offsets to registers in the mailbox (SCB). */
+#define iSCB_STATUS	0x8
+#define iSCB_CMD		0xA
+#define iSCB_CBL		0xC	/* Command BLock offset. */
+#define iSCB_RFA		0xE	/* Rx Frame Area offset. */
+
+/*  Since the 3c507 maps the shared memory window so that the last byte is
+	at 82586 address FFFF, the first byte is at 82586 address 0, 16K, 32K, or
+	48K corresponding to window sizes of 64K, 48K, 32K and 16K respectively.
+	We can account for this be setting the 'SBC Base' entry in the ISCP table
+	below for all the 16 bit offset addresses, and also adding the 'SCB Base'
+	value to all 24 bit physical addresses (in the SCP table and the TX and RX
+	Buffer Descriptors).
+					-Mark
+	*/
+#define SCB_BASE		((unsigned)64*1024 - (dev->mem_end - dev->mem_start))
+
+/*
+  What follows in 'init_words[]' is the "program" that is downloaded to the
+  82586 memory.	 It's mostly tables and command blocks, and starts at the
+  reset address 0xfffff6.  This is designed to be similar to the EtherExpress,
+  thus the unusual location of the SCB at 0x0008.
+
+  Even with the additional "don't care" values, doing it this way takes less
+  program space than initializing the individual tables, and I feel it's much
+  cleaner.
+
+  The databook is particularly useless for the first two structures, I had
+  to use the Crynwr driver as an example.
+
+   The memory setup is as follows:
+   */
+
+#define CONFIG_CMD	0x0018
+#define SET_SA_CMD	0x0024
+#define SA_OFFSET	0x002A
+#define IDLELOOP	0x30
+#define TDR_CMD		0x38
+#define TDR_TIME	0x3C
+#define DUMP_CMD	0x40
+#define DIAG_CMD	0x48
+#define SET_MC_CMD	0x4E
+#define DUMP_DATA	0x56	/* A 170 byte buffer for dump and Set-MC into. */
+
+#define TX_BUF_START	0x0100
+#define NUM_TX_BUFS 	5
+#define TX_BUF_SIZE 	(1518+14+20+16) /* packet+header+TBD */
+
+#define RX_BUF_START	0x2000
+#define RX_BUF_SIZE 	(1518+14+18)	/* packet+header+RBD */
+#define RX_BUF_END		(dev->mem_end - dev->mem_start)
+
+#define TX_TIMEOUT 5
+
+/*
+  That's it: only 86 bytes to set up the beast, including every extra
+  command available.  The 170 byte buffer at DUMP_DATA is shared between the
+  Dump command (called only by the diagnostic program) and the SetMulticastList
+  command.
+
+  To complete the memory setup you only have to write the station address at
+  SA_OFFSET and create the Tx & Rx buffer lists.
+
+  The Tx command chain and buffer list is setup as follows:
+  A Tx command table, with the data buffer pointing to...
+  A Tx data buffer descriptor.  The packet is in a single buffer, rather than
+	chaining together several smaller buffers.
+  A NoOp command, which initially points to itself,
+  And the packet data.
+
+  A transmit is done by filling in the Tx command table and data buffer,
+  re-writing the NoOp command, and finally changing the offset of the last
+  command to point to the current Tx command.  When the Tx command is finished,
+  it jumps to the NoOp, when it loops until the next Tx command changes the
+  "link offset" in the NoOp.  This way the 82586 never has to go through the
+  slow restart sequence.
+
+  The Rx buffer list is set up in the obvious ring structure.  We have enough
+  memory (and low enough interrupt latency) that we can avoid the complicated
+  Rx buffer linked lists by alway associating a full-size Rx data buffer with
+  each Rx data frame.
+
+  I current use four transmit buffers starting at TX_BUF_START (0x0100), and
+  use the rest of memory, from RX_BUF_START to RX_BUF_END, for Rx buffers.
+
+  */
+
+static unsigned short init_words[] = {
+	/*	System Configuration Pointer (SCP). */
+	0x0000,					/* Set bus size to 16 bits. */
+	0,0,					/* pad words. */
+	0x0000,0x0000,			/* ISCP phys addr, set in init_82586_mem(). */
+
+	/*	Intermediate System Configuration Pointer (ISCP). */
+	0x0001,					/* Status word that's cleared when init is done. */
+	0x0008,0,0,				/* SCB offset, (skip, skip) */
+
+	/* System Control Block (SCB). */
+	0,0xf000|RX_START|CUC_START,	/* SCB status and cmd. */
+	CONFIG_CMD,				/* Command list pointer, points to Configure. */
+	RX_BUF_START,				/* Rx block list. */
+	0,0,0,0,				/* Error count: CRC, align, buffer, overrun. */
+
+	/* 0x0018: Configure command.  Change to put MAC data with packet. */
+	0, CmdConfigure,		/* Status, command.		*/
+	SET_SA_CMD,				/* Next command is Set Station Addr. */
+	0x0804,					/* "4" bytes of config data, 8 byte FIFO. */
+	0x2e40,					/* Magic values, including MAC data location. */
+	0,						/* Unused pad word. */
+
+	/* 0x0024: Setup station address command. */
+	0, CmdSASetup,
+	SET_MC_CMD,				/* Next command. */
+	0xaa00,0xb000,0x0bad,	/* Station address (to be filled in) */
+
+	/* 0x0030: NOP, looping back to itself.	 Point to first Tx buffer to Tx. */
+	0, CmdNOp, IDLELOOP, 0 /* pad */,
+
+	/* 0x0038: A unused Time-Domain Reflectometer command. */
+	0, CmdTDR, IDLELOOP, 0,
+
+	/* 0x0040: An unused Dump State command. */
+	0, CmdDump, IDLELOOP, DUMP_DATA,
+
+	/* 0x0048: An unused Diagnose command. */
+	0, CmdDiagnose, IDLELOOP,
+
+	/* 0x004E: An empty set-multicast-list command. */
+	0, CmdMulticastList, IDLELOOP, 0,
+};
+
+/* Index to functions, as function prototypes. */
+
+static int	el16_probe1(struct net_device *dev, int ioaddr);
+static int	el16_open(struct net_device *dev);
+static int	el16_send_packet(struct sk_buff *skb, struct net_device *dev);
+static irqreturn_t el16_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static void el16_rx(struct net_device *dev);
+static int	el16_close(struct net_device *dev);
+static struct net_device_stats *el16_get_stats(struct net_device *dev);
+static void el16_tx_timeout (struct net_device *dev);
+
+static void hardware_send_packet(struct net_device *dev, void *buf, short length, short pad);
+static void init_82586_mem(struct net_device *dev);
+static struct ethtool_ops netdev_ethtool_ops;
+static void init_rx_bufs(struct net_device *);
+
+static int io = 0x300;
+static int irq;
+static int mem_start;
+
+
+/* Check for a network adaptor of this type, and return '0' iff one exists.
+	If dev->base_addr == 0, probe all likely locations.
+	If dev->base_addr == 1, always return failure.
+	If dev->base_addr == 2, (detachable devices only) allocate space for the
+	device and return success.
+	*/
+
+struct net_device * __init el16_probe(int unit)
+{
+	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
+	static unsigned ports[] = { 0x300, 0x320, 0x340, 0x280, 0};
+	unsigned *port;
+	int err = -ENODEV;
+
+	if (!dev)
+		return ERR_PTR(-ENODEV);
+
+	if (unit >= 0) {
+		sprintf(dev->name, "eth%d", unit);
+		netdev_boot_setup_check(dev);
+		io = dev->base_addr;
+		irq = dev->irq;
+		mem_start = dev->mem_start & 15;
+	}
+
+	SET_MODULE_OWNER(dev);
+
+	if (io > 0x1ff) 	/* Check a single specified location. */
+		err = el16_probe1(dev, io);
+	else if (io != 0)
+		err = -ENXIO;		/* Don't probe at all. */
+	else {
+		for (port = ports; *port; port++) {
+			err = el16_probe1(dev, *port);
+			if (!err)
+				break;
+		}
+	}
+
+	if (err)
+		goto out;
+	err = register_netdev(dev);
+	if (err)
+		goto out1;
+	return dev;
+out1:
+	free_irq(dev->irq, dev);
+	iounmap(((struct net_local *)netdev_priv(dev))->base);
+	release_region(dev->base_addr, EL16_IO_EXTENT);
+out:
+	free_netdev(dev);
+	return ERR_PTR(err);
+}
+
+static int __init el16_probe1(struct net_device *dev, int ioaddr)
+{
+	static unsigned char init_ID_done, version_printed;
+	int i, irq, irqval, retval;
+	struct net_local *lp;
+
+	if (init_ID_done == 0) {
+		ushort lrs_state = 0xff;
+		/* Send the ID sequence to the ID_PORT to enable the board(s). */
+		outb(0x00, ID_PORT);
+		for(i = 0; i < 255; i++) {
+			outb(lrs_state, ID_PORT);
+			lrs_state <<= 1;
+			if (lrs_state & 0x100)
+				lrs_state ^= 0xe7;
+		}
+		outb(0x00, ID_PORT);
+		init_ID_done = 1;
+	}
+
+	if (!request_region(ioaddr, EL16_IO_EXTENT, DRV_NAME))
+		return -ENODEV;
+
+	if ((inb(ioaddr) != '*') || (inb(ioaddr + 1) != '3') || 
+	    (inb(ioaddr + 2) != 'C') || (inb(ioaddr + 3) != 'O')) {
+		retval = -ENODEV;
+		goto out;
+	}
+
+	if (net_debug  &&  version_printed++ == 0)
+		printk(version);
+
+	printk("%s: 3c507 at %#x,", dev->name, ioaddr);
+
+	/* We should make a few more checks here, like the first three octets of
+	   the S.A. for the manufacturer's code. */
+
+	irq = inb(ioaddr + IRQ_CONFIG) & 0x0f;
+
+	irqval = request_irq(irq, &el16_interrupt, 0, DRV_NAME, dev);
+	if (irqval) {
+		printk(KERN_ERR "3c507: unable to get IRQ %d (irqval=%d).\n", irq, irqval);
+		retval = -EAGAIN;
+		goto out;
+	}
+
+	/* We've committed to using the board, and can start filling in *dev. */
+	dev->base_addr = ioaddr;
+
+	outb(0x01, ioaddr + MISC_CTRL);
+	for (i = 0; i < 6; i++) {
+		dev->dev_addr[i] = inb(ioaddr + i);
+		printk(" %02x", dev->dev_addr[i]);
+	}
+
+	if (mem_start)
+		net_debug = mem_start & 7;
+
+#ifdef MEM_BASE
+	dev->mem_start = MEM_BASE;
+	dev->mem_end = dev->mem_start + 0x10000;
+#else
+	{
+		int base;
+		int size;
+		char mem_config = inb(ioaddr + MEM_CONFIG);
+		if (mem_config & 0x20) {
+			size = 64*1024;
+			base = 0xf00000 + (mem_config & 0x08 ? 0x080000
+							   : ((mem_config & 3) << 17));
+		} else {
+			size = ((mem_config & 3) + 1) << 14;
+			base = 0x0c0000 + ( (mem_config & 0x18) << 12);
+		}
+		dev->mem_start = base;
+		dev->mem_end = base + size;
+	}
+#endif
+
+	dev->if_port = (inb(ioaddr + ROM_CONFIG) & 0x80) ? 1 : 0;
+	dev->irq = inb(ioaddr + IRQ_CONFIG) & 0x0f;
+
+	printk(", IRQ %d, %sternal xcvr, memory %#lx-%#lx.\n", dev->irq,
+		   dev->if_port ? "ex" : "in", dev->mem_start, dev->mem_end-1);
+
+	if (net_debug)
+		printk(version);
+
+	lp = netdev_priv(dev);
+ 	memset(lp, 0, sizeof(*lp));
+	spin_lock_init(&lp->lock);
+	lp->base = ioremap(dev->mem_start, RX_BUF_END);
+	if (!lp->base) {
+		printk(KERN_ERR "3c507: unable to remap memory\n");
+		retval = -EAGAIN;
+		goto out1;
+	}
+
+ 	dev->open = el16_open;
+ 	dev->stop = el16_close;
+	dev->hard_start_xmit = el16_send_packet;
+	dev->get_stats	= el16_get_stats;
+	dev->tx_timeout = el16_tx_timeout;
+	dev->watchdog_timeo = TX_TIMEOUT;
+	dev->ethtool_ops = &netdev_ethtool_ops;
+ 	dev->flags &= ~IFF_MULTICAST;	/* Multicast doesn't work */
+	return 0;
+out1:
+	free_irq(dev->irq, dev);
+out:
+	release_region(ioaddr, EL16_IO_EXTENT);
+	return retval;
+}
+
+static int el16_open(struct net_device *dev)
+{
+	/* Initialize the 82586 memory and start it. */
+	init_82586_mem(dev);
+
+	netif_start_queue(dev);
+	return 0;
+}
+
+
+static void el16_tx_timeout (struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+	void __iomem *shmem = lp->base;
+
+	if (net_debug > 1)
+		printk ("%s: transmit timed out, %s?  ", dev->name,
+			readw(shmem + iSCB_STATUS) & 0x8000 ? "IRQ conflict" :
+			"network cable problem");
+	/* Try to restart the adaptor. */
+	if (lp->last_restart == lp->stats.tx_packets) {
+		if (net_debug > 1)
+			printk ("Resetting board.\n");
+		/* Completely reset the adaptor. */
+		init_82586_mem (dev);
+		lp->tx_pkts_in_ring = 0;
+	} else {
+		/* Issue the channel attention signal and hope it "gets better". */
+		if (net_debug > 1)
+			printk ("Kicking board.\n");
+		writew(0xf000 | CUC_START | RX_START, shmem + iSCB_CMD);
+		outb (0, ioaddr + SIGNAL_CA);	/* Issue channel-attn. */
+		lp->last_restart = lp->stats.tx_packets;
+	}
+	dev->trans_start = jiffies;
+	netif_wake_queue (dev);
+}
+
+
+static int el16_send_packet (struct sk_buff *skb, struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+	unsigned long flags;
+	short length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
+	unsigned char *buf = skb->data;
+
+	netif_stop_queue (dev);
+
+	spin_lock_irqsave (&lp->lock, flags);
+
+	lp->stats.tx_bytes += length;
+	/* Disable the 82586's input to the interrupt line. */
+	outb (0x80, ioaddr + MISC_CTRL);
+
+	hardware_send_packet (dev, buf, skb->len, length - skb->len);
+
+	dev->trans_start = jiffies;
+	/* Enable the 82586 interrupt input. */
+	outb (0x84, ioaddr + MISC_CTRL);
+
+	spin_unlock_irqrestore (&lp->lock, flags);
+
+	dev_kfree_skb (skb);
+
+	/* You might need to clean up and record Tx statistics here. */
+
+	return 0;
+}
+
+/*	The typical workload of the driver:
+	Handle the network interface interrupts. */
+static irqreturn_t el16_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct net_device *dev = dev_id;
+	struct net_local *lp;
+	int ioaddr, status, boguscount = 0;
+	ushort ack_cmd = 0;
+	void __iomem *shmem;
+
+	if (dev == NULL) {
+		printk ("net_interrupt(): irq %d for unknown device.\n", irq);
+		return IRQ_NONE;
+	}
+
+	ioaddr = dev->base_addr;
+	lp = netdev_priv(dev);
+	shmem = lp->base;
+
+	spin_lock(&lp->lock);
+
+	status = readw(shmem+iSCB_STATUS);
+
+	if (net_debug > 4) {
+		printk("%s: 3c507 interrupt, status %4.4x.\n", dev->name, status);
+	}
+
+	/* Disable the 82586's input to the interrupt line. */
+	outb(0x80, ioaddr + MISC_CTRL);
+
+	/* Reap the Tx packet buffers. */
+	while (lp->tx_pkts_in_ring) {
+	  unsigned short tx_status = readw(shmem+lp->tx_reap);
+	  if (!(tx_status & 0x8000)) {
+		if (net_debug > 5) 
+			printk("Tx command incomplete (%#x).\n", lp->tx_reap);
+		break;
+	  }
+	  /* Tx unsuccessful or some interesting status bit set. */
+	  if (!(tx_status & 0x2000) || (tx_status & 0x0f3f)) {
+		lp->stats.tx_errors++;
+		if (tx_status & 0x0600)  lp->stats.tx_carrier_errors++;
+		if (tx_status & 0x0100)  lp->stats.tx_fifo_errors++;
+		if (!(tx_status & 0x0040))  lp->stats.tx_heartbeat_errors++;
+		if (tx_status & 0x0020)  lp->stats.tx_aborted_errors++;
+		lp->stats.collisions += tx_status & 0xf;
+	  }
+	  lp->stats.tx_packets++;
+	  if (net_debug > 5)
+		  printk("Reaped %x, Tx status %04x.\n" , lp->tx_reap, tx_status);
+	  lp->tx_reap += TX_BUF_SIZE;
+	  if (lp->tx_reap > RX_BUF_START - TX_BUF_SIZE)
+		lp->tx_reap = TX_BUF_START;
+
+	  lp->tx_pkts_in_ring--;
+	  /* There is always more space in the Tx ring buffer now. */
+	  netif_wake_queue(dev);
+
+	  if (++boguscount > 10)
+		break;
+	}
+
+	if (status & 0x4000) { /* Packet received. */
+		if (net_debug > 5)
+			printk("Received packet, rx_head %04x.\n", lp->rx_head);
+		el16_rx(dev);
+	}
+
+	/* Acknowledge the interrupt sources. */
+	ack_cmd = status & 0xf000;
+
+	if ((status & 0x0700) != 0x0200 && netif_running(dev)) {
+		if (net_debug)
+			printk("%s: Command unit stopped, status %04x, restarting.\n",
+				   dev->name, status);
+		/* If this ever occurs we should really re-write the idle loop, reset
+		   the Tx list, and do a complete restart of the command unit.
+		   For now we rely on the Tx timeout if the resume doesn't work. */
+		ack_cmd |= CUC_RESUME;
+	}
+
+	if ((status & 0x0070) != 0x0040 && netif_running(dev)) {
+		/* The Rx unit is not ready, it must be hung.  Restart the receiver by
+		   initializing the rx buffers, and issuing an Rx start command. */
+		if (net_debug)
+			printk("%s: Rx unit stopped, status %04x, restarting.\n",
+				   dev->name, status);
+		init_rx_bufs(dev);
+		writew(RX_BUF_START,shmem+iSCB_RFA);
+		ack_cmd |= RX_START;
+	}
+
+	writew(ack_cmd,shmem+iSCB_CMD);
+	outb(0, ioaddr + SIGNAL_CA);			/* Issue channel-attn. */
+
+	/* Clear the latched interrupt. */
+	outb(0, ioaddr + RESET_IRQ);
+
+	/* Enable the 82586's interrupt input. */
+	outb(0x84, ioaddr + MISC_CTRL);
+	spin_unlock(&lp->lock);
+	return IRQ_HANDLED;
+}
+
+static int el16_close(struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+	void __iomem *shmem = lp->base;
+
+	netif_stop_queue(dev);
+
+	/* Flush the Tx and disable Rx. */
+	writew(RX_SUSPEND | CUC_SUSPEND,shmem+iSCB_CMD);
+	outb(0, ioaddr + SIGNAL_CA);
+
+	/* Disable the 82586's input to the interrupt line. */
+	outb(0x80, ioaddr + MISC_CTRL);
+
+	/* We always physically use the IRQ line, so we don't do free_irq(). */
+
+	/* Update the statistics here. */
+
+	return 0;
+}
+
+/* Get the current statistics.	This may be called with the card open or
+   closed. */
+static struct net_device_stats *el16_get_stats(struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+
+	/* ToDo: decide if there are any useful statistics from the SCB. */
+
+	return &lp->stats;
+}
+
+/* Initialize the Rx-block list. */
+static void init_rx_bufs(struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	void __iomem *write_ptr;
+	unsigned short SCB_base = SCB_BASE;
+
+	int cur_rxbuf = lp->rx_head = RX_BUF_START;
+
+	/* Initialize each Rx frame + data buffer. */
+	do {	/* While there is room for one more. */
+
+		write_ptr = lp->base + cur_rxbuf;
+
+		writew(0x0000,write_ptr);			/* Status */
+		writew(0x0000,write_ptr+=2);			/* Command */
+		writew(cur_rxbuf + RX_BUF_SIZE,write_ptr+=2);	/* Link */
+		writew(cur_rxbuf + 22,write_ptr+=2);		/* Buffer offset */
+		writew(0x0000,write_ptr+=2);			/* Pad for dest addr. */
+		writew(0x0000,write_ptr+=2);
+		writew(0x0000,write_ptr+=2);
+		writew(0x0000,write_ptr+=2);			/* Pad for source addr. */
+		writew(0x0000,write_ptr+=2);
+		writew(0x0000,write_ptr+=2);
+		writew(0x0000,write_ptr+=2);			/* Pad for protocol. */
+
+		writew(0x0000,write_ptr+=2);			/* Buffer: Actual count */
+		writew(-1,write_ptr+=2);			/* Buffer: Next (none). */
+		writew(cur_rxbuf + 0x20 + SCB_base,write_ptr+=2);/* Buffer: Address low */
+		writew(0x0000,write_ptr+=2);
+		/* Finally, the number of bytes in the buffer. */
+		writew(0x8000 + RX_BUF_SIZE-0x20,write_ptr+=2);
+
+		lp->rx_tail = cur_rxbuf;
+		cur_rxbuf += RX_BUF_SIZE;
+	} while (cur_rxbuf <= RX_BUF_END - RX_BUF_SIZE);
+
+	/* Terminate the list by setting the EOL bit, and wrap the pointer to make
+	   the list a ring. */
+	write_ptr = lp->base + lp->rx_tail + 2;
+	writew(0xC000,write_ptr);				/* Command, mark as last. */
+	writew(lp->rx_head,write_ptr+2);			/* Link */
+}
+
+static void init_82586_mem(struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	short ioaddr = dev->base_addr;
+	void __iomem *shmem = lp->base;
+
+	/* Enable loopback to protect the wire while starting up,
+	   and hold the 586 in reset during the memory initialization. */
+	outb(0x20, ioaddr + MISC_CTRL);
+
+	/* Fix the ISCP address and base. */
+	init_words[3] = SCB_BASE;
+	init_words[7] = SCB_BASE;
+
+	/* Write the words at 0xfff6 (address-aliased to 0xfffff6). */
+	memcpy_toio(lp->base + RX_BUF_END - 10, init_words, 10);
+
+	/* Write the words at 0x0000. */
+	memcpy_toio(lp->base, init_words + 5, sizeof(init_words) - 10);
+
+	/* Fill in the station address. */
+	memcpy_toio(lp->base+SA_OFFSET, dev->dev_addr,
+		   sizeof(dev->dev_addr));
+
+	/* The Tx-block list is written as needed.  We just set up the values. */
+	lp->tx_cmd_link = IDLELOOP + 4;
+	lp->tx_head = lp->tx_reap = TX_BUF_START;
+
+	init_rx_bufs(dev);
+
+	/* Start the 586 by releasing the reset line, but leave loopback. */
+	outb(0xA0, ioaddr + MISC_CTRL);
+
+	/* This was time consuming to track down: you need to give two channel
+	   attention signals to reliably start up the i82586. */
+	outb(0, ioaddr + SIGNAL_CA);
+
+	{
+		int boguscnt = 50;
+		while (readw(shmem+iSCB_STATUS) == 0)
+			if (--boguscnt == 0) {
+				printk("%s: i82586 initialization timed out with status %04x,"
+					   "cmd %04x.\n", dev->name,
+					   readw(shmem+iSCB_STATUS), readw(shmem+iSCB_CMD));
+				break;
+			}
+		/* Issue channel-attn -- the 82586 won't start. */
+		outb(0, ioaddr + SIGNAL_CA);
+	}
+
+	/* Disable loopback and enable interrupts. */
+	outb(0x84, ioaddr + MISC_CTRL);
+	if (net_debug > 4)
+		printk("%s: Initialized 82586, status %04x.\n", dev->name,
+			   readw(shmem+iSCB_STATUS));
+	return;
+}
+
+static void hardware_send_packet(struct net_device *dev, void *buf, short length, short pad)
+{
+	struct net_local *lp = netdev_priv(dev);
+	short ioaddr = dev->base_addr;
+	ushort tx_block = lp->tx_head;
+	void __iomem *write_ptr = lp->base + tx_block;
+	static char padding[ETH_ZLEN];
+
+	/* Set the write pointer to the Tx block, and put out the header. */
+	writew(0x0000,write_ptr);			/* Tx status */
+	writew(CMD_INTR|CmdTx,write_ptr+=2);		/* Tx command */
+	writew(tx_block+16,write_ptr+=2);		/* Next command is a NoOp. */
+	writew(tx_block+8,write_ptr+=2);			/* Data Buffer offset. */
+
+	/* Output the data buffer descriptor. */
+	writew((pad + length) | 0x8000,write_ptr+=2);		/* Byte count parameter. */
+	writew(-1,write_ptr+=2);			/* No next data buffer. */
+	writew(tx_block+22+SCB_BASE,write_ptr+=2);	/* Buffer follows the NoOp command. */
+	writew(0x0000,write_ptr+=2);			/* Buffer address high bits (always zero). */
+
+	/* Output the Loop-back NoOp command. */
+	writew(0x0000,write_ptr+=2);			/* Tx status */
+	writew(CmdNOp,write_ptr+=2);			/* Tx command */
+	writew(tx_block+16,write_ptr+=2);		/* Next is myself. */
+
+	/* Output the packet at the write pointer. */
+	memcpy_toio(write_ptr+2, buf, length);
+	if (pad)
+		memcpy_toio(write_ptr+length+2, padding, pad);
+
+	/* Set the old command link pointing to this send packet. */
+	writew(tx_block,lp->base + lp->tx_cmd_link);
+	lp->tx_cmd_link = tx_block + 20;
+
+	/* Set the next free tx region. */
+	lp->tx_head = tx_block + TX_BUF_SIZE;
+	if (lp->tx_head > RX_BUF_START - TX_BUF_SIZE)
+		lp->tx_head = TX_BUF_START;
+
+	if (net_debug > 4) {
+		printk("%s: 3c507 @%x send length = %d, tx_block %3x, next %3x.\n",
+			   dev->name, ioaddr, length, tx_block, lp->tx_head);
+	}
+
+	/* Grimly block further packets if there has been insufficient reaping. */
+	if (++lp->tx_pkts_in_ring < NUM_TX_BUFS) 
+		netif_wake_queue(dev);
+}
+
+static void el16_rx(struct net_device *dev)
+{
+	struct net_local *lp = netdev_priv(dev);
+	void __iomem *shmem = lp->base;
+	ushort rx_head = lp->rx_head;
+	ushort rx_tail = lp->rx_tail;
+	ushort boguscount = 10;
+	short frame_status;
+
+	while ((frame_status = readw(shmem+rx_head)) < 0) {   /* Command complete */
+		void __iomem *read_frame = lp->base + rx_head;
+		ushort rfd_cmd = readw(read_frame+2);
+		ushort next_rx_frame = readw(read_frame+4);
+		ushort data_buffer_addr = readw(read_frame+6);
+		void __iomem *data_frame = lp->base + data_buffer_addr;
+		ushort pkt_len = readw(data_frame);
+
+		if (rfd_cmd != 0 || data_buffer_addr != rx_head + 22
+			|| (pkt_len & 0xC000) != 0xC000) {
+			printk("%s: Rx frame at %#x corrupted, status %04x cmd %04x"
+				   "next %04x data-buf @%04x %04x.\n", dev->name, rx_head,
+				   frame_status, rfd_cmd, next_rx_frame, data_buffer_addr,
+				   pkt_len);
+		} else if ((frame_status & 0x2000) == 0) {
+			/* Frame Rxed, but with error. */
+			lp->stats.rx_errors++;
+			if (frame_status & 0x0800) lp->stats.rx_crc_errors++;
+			if (frame_status & 0x0400) lp->stats.rx_frame_errors++;
+			if (frame_status & 0x0200) lp->stats.rx_fifo_errors++;
+			if (frame_status & 0x0100) lp->stats.rx_over_errors++;
+			if (frame_status & 0x0080) lp->stats.rx_length_errors++;
+		} else {
+			/* Malloc up new buffer. */
+			struct sk_buff *skb;
+
+			pkt_len &= 0x3fff;
+			skb = dev_alloc_skb(pkt_len+2);
+			if (skb == NULL) {
+				printk("%s: Memory squeeze, dropping packet.\n", dev->name);
+				lp->stats.rx_dropped++;
+				break;
+			}
+
+			skb_reserve(skb,2);
+			skb->dev = dev;
+
+			/* 'skb->data' points to the start of sk_buff data area. */
+			memcpy_fromio(skb_put(skb,pkt_len), data_frame + 10, pkt_len);
+
+			skb->protocol=eth_type_trans(skb,dev);
+			netif_rx(skb);
+			dev->last_rx = jiffies;
+			lp->stats.rx_packets++;
+			lp->stats.rx_bytes += pkt_len;
+		}
+
+		/* Clear the status word and set End-of-List on the rx frame. */
+		writew(0,read_frame);
+		writew(0xC000,read_frame+2);
+		/* Clear the end-of-list on the prev. RFD. */
+		writew(0x0000,lp->base + rx_tail + 2);
+
+		rx_tail = rx_head;
+		rx_head = next_rx_frame;
+		if (--boguscount == 0)
+			break;
+	}
+
+	lp->rx_head = rx_head;
+	lp->rx_tail = rx_tail;
+}
+
+static void netdev_get_drvinfo(struct net_device *dev,
+			       struct ethtool_drvinfo *info)
+{
+	strcpy(info->driver, DRV_NAME);
+	strcpy(info->version, DRV_VERSION);
+	sprintf(info->bus_info, "ISA 0x%lx", dev->base_addr);
+}
+
+static u32 netdev_get_msglevel(struct net_device *dev)
+{
+	return debug;
+}
+
+static void netdev_set_msglevel(struct net_device *dev, u32 level)
+{
+	debug = level;
+}
+
+static struct ethtool_ops netdev_ethtool_ops = {
+	.get_drvinfo		= netdev_get_drvinfo,
+	.get_msglevel		= netdev_get_msglevel,
+	.set_msglevel		= netdev_set_msglevel,
+};
+
+#ifdef MODULE
+static struct net_device *dev_3c507;
+module_param(io, int, 0);
+module_param(irq, int, 0);
+MODULE_PARM_DESC(io, "EtherLink16 I/O base address");
+MODULE_PARM_DESC(irq, "(ignored)");
+
+int init_module(void)
+{
+	if (io == 0)
+		printk("3c507: You should not use auto-probing with insmod!\n");
+	dev_3c507 = el16_probe(-1);
+	return IS_ERR(dev_3c507) ? PTR_ERR(dev_3c507) : 0;
+}
+
+void
+cleanup_module(void)
+{
+	struct net_device *dev = dev_3c507;
+	unregister_netdev(dev);
+	free_irq(dev->irq, dev);
+	iounmap(((struct net_local *)netdev_priv(dev))->base);
+	release_region(dev->base_addr, EL16_IO_EXTENT);
+	free_netdev(dev);
+}
+#endif /* MODULE */
+MODULE_LICENSE("GPL");
+
+
+/*
+ * Local variables:
+ *  compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -I/usr/src/linux/drivers/net -Wall -Wstrict-prototypes -O6 -m486 -c 3c507.c"
+ *  version-control: t
+ *  kept-new-versions: 5
+ *  tab-width: 4
+ *  c-indent-level: 4
+ * End:
+ */