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, 1675 insertions, 0 deletions

diff --git a/drivers/net/3c527.c b/drivers/net/3c527.c
new file mode 100644
index 00000000000..6db3301e796
--- /dev/null
+++ b/drivers/net/3c527.c
@@ -0,0 +1,1675 @@
+/* 3c527.c: 3Com Etherlink/MC32 driver for Linux 2.4 and 2.6.
+ *
+ *	(c) Copyright 1998 Red Hat Software Inc
+ *	Written by Alan Cox. 
+ *	Further debugging by Carl Drougge.
+ *      Initial SMP support by Felipe W Damasio <felipewd@terra.com.br>
+ *      Heavily modified by Richard Procter <rnp@paradise.net.nz>
+ *
+ *	Based on skeleton.c written 1993-94 by Donald Becker and ne2.c
+ *	(for the MCA stuff) written by Wim Dumon.
+ *
+ *	Thanks to 3Com for making this possible by providing me with the
+ *	documentation.
+ *
+ *	This software may be used and distributed according to the terms
+ *	of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#define DRV_NAME		"3c527"
+#define DRV_VERSION		"0.7-SMP"
+#define DRV_RELDATE		"2003/09/21"
+
+static const char *version =
+DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " Richard Procter <rnp@paradise.net.nz>\n";
+
+/**
+ * DOC: Traps for the unwary
+ *
+ *	The diagram (Figure 1-1) and the POS summary disagree with the
+ *	"Interrupt Level" section in the manual.
+ *
+ *	The manual contradicts itself when describing the minimum number 
+ *	buffers in the 'configure lists' command. 
+ *	My card accepts a buffer config of 4/4. 
+ *
+ *	Setting the SAV BP bit does not save bad packets, but
+ *	only enables RX on-card stats collection. 
+ *
+ *	The documentation in places seems to miss things. In actual fact
+ *	I've always eventually found everything is documented, it just
+ *	requires careful study.
+ *
+ * DOC: Theory Of Operation
+ *
+ *	The 3com 3c527 is a 32bit MCA bus mastering adapter with a large
+ *	amount of on board intelligence that housekeeps a somewhat dumber
+ *	Intel NIC. For performance we want to keep the transmit queue deep
+ *	as the card can transmit packets while fetching others from main
+ *	memory by bus master DMA. Transmission and reception are driven by
+ *	circular buffer queues.
+ *
+ *	The mailboxes can be used for controlling how the card traverses
+ *	its buffer rings, but are used only for inital setup in this
+ *	implementation.  The exec mailbox allows a variety of commands to
+ *	be executed. Each command must complete before the next is
+ *	executed. Primarily we use the exec mailbox for controlling the
+ *	multicast lists.  We have to do a certain amount of interesting
+ *	hoop jumping as the multicast list changes can occur in interrupt
+ *	state when the card has an exec command pending. We defer such
+ *	events until the command completion interrupt.
+ *
+ *	A copy break scheme (taken from 3c59x.c) is employed whereby
+ *	received frames exceeding a configurable length are passed
+ *	directly to the higher networking layers without incuring a copy,
+ *	in what amounts to a time/space trade-off.
+ *	 
+ *	The card also keeps a large amount of statistical information
+ *	on-board. In a perfect world, these could be used safely at no
+ *	cost. However, lacking information to the contrary, processing
+ *	them without races would involve so much extra complexity as to
+ *	make it unworthwhile to do so. In the end, a hybrid SW/HW
+ *	implementation was made necessary --- see mc32_update_stats().  
+ *
+ * DOC: Notes
+ *	
+ *	It should be possible to use two or more cards, but at this stage
+ *	only by loading two copies of the same module.
+ *
+ *	The on-board 82586 NIC has trouble receiving multiple
+ *	back-to-back frames and so is likely to drop packets from fast
+ *	senders.
+**/
+
+#include <linux/module.h>
+
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/mca-legacy.h>
+#include <linux/ioport.h>
+#include <linux/in.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/wait.h>
+#include <linux/ethtool.h>
+#include <linux/completion.h>
+#include <linux/bitops.h>
+
+#include <asm/semaphore.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+
+#include "3c527.h"
+
+MODULE_LICENSE("GPL");
+
+/*
+ * The name of the card. Is used for messages and in the requests for
+ * io regions, irqs and dma channels
+ */
+static const char* cardname = DRV_NAME;
+
+/* use 0 for production, 1 for verification, >2 for debug */
+#ifndef NET_DEBUG
+#define NET_DEBUG 2
+#endif
+
+#undef DEBUG_IRQ
+
+static unsigned int mc32_debug = NET_DEBUG;
+
+/* The number of low I/O ports used by the ethercard. */
+#define MC32_IO_EXTENT	8
+
+/* As implemented, values must be a power-of-2 -- 4/8/16/32 */ 
+#define TX_RING_LEN     32       /* Typically the card supports 37  */
+#define RX_RING_LEN     8        /*     "       "        "          */
+
+/* Copy break point, see above for details. 
+ * Setting to > 1512 effectively disables this feature.	*/	    
+#define RX_COPYBREAK    200      /* Value from 3c59x.c */
+
+/* Issue the 82586 workaround command - this is for "busy lans", but
+ * basically means for all lans now days - has a performance (latency) 
+ * cost, but best set. */ 
+static const int WORKAROUND_82586=1;
+
+/* Pointers to buffers and their on-card records */
+struct mc32_ring_desc 
+{
+	volatile struct skb_header *p;                    
+	struct sk_buff *skb;          
+};
+
+/* Information that needs to be kept for each board. */
+struct mc32_local 
+{
+	int slot;
+
+	u32 base;
+	struct net_device_stats net_stats;
+	volatile struct mc32_mailbox *rx_box;
+	volatile struct mc32_mailbox *tx_box;
+	volatile struct mc32_mailbox *exec_box;
+        volatile struct mc32_stats *stats;    /* Start of on-card statistics */
+        u16 tx_chain;           /* Transmit list start offset */
+	u16 rx_chain;           /* Receive list start offset */
+        u16 tx_len;             /* Transmit list count */ 
+        u16 rx_len;             /* Receive list count */
+
+	u16 xceiver_desired_state; /* HALTED or RUNNING */
+	u16 cmd_nonblocking;    /* Thread is uninterested in command result */
+	u16 mc_reload_wait;	/* A multicast load request is pending */
+	u32 mc_list_valid;	/* True when the mclist is set */
+
+	struct mc32_ring_desc tx_ring[TX_RING_LEN];	/* Host Transmit ring */
+	struct mc32_ring_desc rx_ring[RX_RING_LEN];	/* Host Receive ring */
+
+	atomic_t tx_count;	/* buffers left */
+	atomic_t tx_ring_head;  /* index to tx en-queue end */
+	u16 tx_ring_tail;       /* index to tx de-queue end */
+
+	u16 rx_ring_tail;       /* index to rx de-queue end */ 
+
+	struct semaphore cmd_mutex;    /* Serialises issuing of execute commands */
+        struct completion execution_cmd; /* Card has completed an execute command */
+	struct completion xceiver_cmd;   /* Card has completed a tx or rx command */
+};
+
+/* The station (ethernet) address prefix, used for a sanity check. */
+#define SA_ADDR0 0x02
+#define SA_ADDR1 0x60
+#define SA_ADDR2 0xAC
+
+struct mca_adapters_t {
+	unsigned int	id;
+	char		*name;
+};
+
+static const struct mca_adapters_t mc32_adapters[] = {
+	{ 0x0041, "3COM EtherLink MC/32" },
+	{ 0x8EF5, "IBM High Performance Lan Adapter" },
+	{ 0x0000, NULL }
+};
+
+
+/* Macros for ring index manipulations */ 
+static inline u16 next_rx(u16 rx) { return (rx+1)&(RX_RING_LEN-1); };
+static inline u16 prev_rx(u16 rx) { return (rx-1)&(RX_RING_LEN-1); };
+
+static inline u16 next_tx(u16 tx) { return (tx+1)&(TX_RING_LEN-1); };
+
+
+/* Index to functions, as function prototypes. */
+static int	mc32_probe1(struct net_device *dev, int ioaddr);
+static int      mc32_command(struct net_device *dev, u16 cmd, void *data, int len);
+static int	mc32_open(struct net_device *dev);
+static void	mc32_timeout(struct net_device *dev);
+static int	mc32_send_packet(struct sk_buff *skb, struct net_device *dev);
+static irqreturn_t mc32_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+static int	mc32_close(struct net_device *dev);
+static struct	net_device_stats *mc32_get_stats(struct net_device *dev);
+static void	mc32_set_multicast_list(struct net_device *dev);
+static void	mc32_reset_multicast_list(struct net_device *dev);
+static struct ethtool_ops netdev_ethtool_ops;
+
+static void cleanup_card(struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	unsigned slot = lp->slot;
+	mca_mark_as_unused(slot);
+	mca_set_adapter_name(slot, NULL);
+	free_irq(dev->irq, dev);
+	release_region(dev->base_addr, MC32_IO_EXTENT);
+}
+
+/**
+ * mc32_probe 	-	Search for supported boards
+ * @unit: interface number to use
+ *
+ * Because MCA bus is a real bus and we can scan for cards we could do a
+ * single scan for all boards here. Right now we use the passed in device
+ * structure and scan for only one board. This needs fixing for modules
+ * in particular.
+ */
+
+struct net_device *__init mc32_probe(int unit)
+{
+	struct net_device *dev = alloc_etherdev(sizeof(struct mc32_local));
+	static int current_mca_slot = -1;
+	int i;
+	int err;
+
+	if (!dev)
+		return ERR_PTR(-ENOMEM);
+
+	if (unit >= 0)
+		sprintf(dev->name, "eth%d", unit);
+
+	SET_MODULE_OWNER(dev);
+
+	/* Do not check any supplied i/o locations. 
+	   POS registers usually don't fail :) */
+
+	/* MCA cards have POS registers.  
+	   Autodetecting MCA cards is extremely simple. 
+	   Just search for the card. */
+
+	for(i = 0; (mc32_adapters[i].name != NULL); i++) {
+		current_mca_slot = 
+			mca_find_unused_adapter(mc32_adapters[i].id, 0);
+
+		if(current_mca_slot != MCA_NOTFOUND) {
+			if(!mc32_probe1(dev, current_mca_slot))
+			{
+				mca_set_adapter_name(current_mca_slot, 
+						mc32_adapters[i].name);
+				mca_mark_as_used(current_mca_slot);
+				err = register_netdev(dev);
+				if (err) {
+					cleanup_card(dev);
+					free_netdev(dev);
+					dev = ERR_PTR(err);
+				}
+				return dev;
+			}
+			
+		}
+	}
+	free_netdev(dev);
+	return ERR_PTR(-ENODEV);
+}
+
+/**
+ * mc32_probe1	-	Check a given slot for a board and test the card
+ * @dev:  Device structure to fill in
+ * @slot: The MCA bus slot being used by this card
+ *
+ * Decode the slot data and configure the card structures. Having done this we
+ * can reset the card and configure it. The card does a full self test cycle
+ * in firmware so we have to wait for it to return and post us either a 
+ * failure case or some addresses we use to find the board internals.
+ */
+
+static int __init mc32_probe1(struct net_device *dev, int slot)
+{
+	static unsigned version_printed;
+	int i, err;
+	u8 POS;
+	u32 base;
+	struct mc32_local *lp = netdev_priv(dev);
+	static u16 mca_io_bases[]={
+		0x7280,0x7290,
+		0x7680,0x7690,
+		0x7A80,0x7A90,
+		0x7E80,0x7E90
+	};
+	static u32 mca_mem_bases[]={
+		0x00C0000,
+		0x00C4000,
+		0x00C8000,
+		0x00CC000,
+		0x00D0000,
+		0x00D4000,
+		0x00D8000,
+		0x00DC000
+	};
+	static char *failures[]={
+		"Processor instruction",
+		"Processor data bus",
+		"Processor data bus",
+		"Processor data bus",
+		"Adapter bus",
+		"ROM checksum",
+		"Base RAM",
+		"Extended RAM",
+		"82586 internal loopback",
+		"82586 initialisation failure",
+		"Adapter list configuration error"
+	};
+
+	/* Time to play MCA games */
+
+	if (mc32_debug  &&  version_printed++ == 0)
+		printk(KERN_DEBUG "%s", version);
+
+	printk(KERN_INFO "%s: %s found in slot %d:", dev->name, cardname, slot);
+
+	POS = mca_read_stored_pos(slot, 2);
+	
+	if(!(POS&1))
+	{
+		printk(" disabled.\n");
+		return -ENODEV;
+	}
+
+	/* Fill in the 'dev' fields. */
+	dev->base_addr = mca_io_bases[(POS>>1)&7];
+	dev->mem_start = mca_mem_bases[(POS>>4)&7];
+	
+	POS = mca_read_stored_pos(slot, 4);
+	if(!(POS&1))
+	{
+		printk("memory window disabled.\n");
+		return -ENODEV;
+	}
+
+	POS = mca_read_stored_pos(slot, 5);
+	
+	i=(POS>>4)&3;
+	if(i==3)
+	{
+		printk("invalid memory window.\n");
+		return -ENODEV;
+	}
+	
+	i*=16384;
+	i+=16384;
+	
+	dev->mem_end=dev->mem_start + i;
+	
+	dev->irq = ((POS>>2)&3)+9;
+	
+	if(!request_region(dev->base_addr, MC32_IO_EXTENT, cardname))
+	{
+		printk("io 0x%3lX, which is busy.\n", dev->base_addr);
+		return -EBUSY;
+	}
+
+	printk("io 0x%3lX irq %d mem 0x%lX (%dK)\n",
+		dev->base_addr, dev->irq, dev->mem_start, i/1024);
+	
+	
+	/* We ought to set the cache line size here.. */
+	
+	
+	/*
+	 *	Go PROM browsing
+	 */
+	 
+	printk("%s: Address ", dev->name);
+	 
+	/* Retrieve and print the ethernet address. */
+	for (i = 0; i < 6; i++)
+	{
+		mca_write_pos(slot, 6, i+12);
+		mca_write_pos(slot, 7, 0);
+	
+		printk(" %2.2x", dev->dev_addr[i] = mca_read_pos(slot,3));
+	}
+
+	mca_write_pos(slot, 6, 0);
+	mca_write_pos(slot, 7, 0);
+
+	POS = mca_read_stored_pos(slot, 4);
+	
+	if(POS&2)
+		printk(" : BNC port selected.\n");
+	else 
+		printk(" : AUI port selected.\n");
+		
+	POS=inb(dev->base_addr+HOST_CTRL);
+	POS|=HOST_CTRL_ATTN|HOST_CTRL_RESET;
+	POS&=~HOST_CTRL_INTE;
+	outb(POS, dev->base_addr+HOST_CTRL);
+	/* Reset adapter */
+	udelay(100);
+	/* Reset off */
+	POS&=~(HOST_CTRL_ATTN|HOST_CTRL_RESET);
+	outb(POS, dev->base_addr+HOST_CTRL);
+	
+	udelay(300);
+	
+	/*
+	 *	Grab the IRQ
+	 */
+
+	err = request_irq(dev->irq, &mc32_interrupt, SA_SHIRQ | SA_SAMPLE_RANDOM, DRV_NAME, dev);
+	if (err) {
+		release_region(dev->base_addr, MC32_IO_EXTENT);
+		printk(KERN_ERR "%s: unable to get IRQ %d.\n", DRV_NAME, dev->irq);
+		goto err_exit_ports;
+	}
+
+	memset(lp, 0, sizeof(struct mc32_local));
+	lp->slot = slot;
+
+	i=0;
+
+	base = inb(dev->base_addr);
+	
+	while(base == 0xFF)
+	{
+		i++;
+		if(i == 1000)
+		{
+			printk(KERN_ERR "%s: failed to boot adapter.\n", dev->name);
+			err = -ENODEV; 
+			goto err_exit_irq;
+		}
+		udelay(1000);
+		if(inb(dev->base_addr+2)&(1<<5))
+			base = inb(dev->base_addr);
+	}
+
+	if(base>0)
+	{
+		if(base < 0x0C)
+			printk(KERN_ERR "%s: %s%s.\n", dev->name, failures[base-1],
+				base<0x0A?" test failure":"");
+		else
+			printk(KERN_ERR "%s: unknown failure %d.\n", dev->name, base);
+		err = -ENODEV; 
+		goto err_exit_irq;
+	}
+	
+	base=0;
+	for(i=0;i<4;i++)
+	{
+		int n=0;
+	
+		while(!(inb(dev->base_addr+2)&(1<<5)))
+		{
+			n++;
+			udelay(50);
+			if(n>100)
+			{
+				printk(KERN_ERR "%s: mailbox read fail (%d).\n", dev->name, i);
+				err = -ENODEV;
+				goto err_exit_irq;
+			}
+		}
+
+		base|=(inb(dev->base_addr)<<(8*i));
+	}
+	
+	lp->exec_box=isa_bus_to_virt(dev->mem_start+base);
+	
+	base=lp->exec_box->data[1]<<16|lp->exec_box->data[0];  
+	
+	lp->base = dev->mem_start+base;
+	
+	lp->rx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[2]); 
+	lp->tx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[3]);
+	
+	lp->stats = isa_bus_to_virt(lp->base + lp->exec_box->data[5]);
+
+	/*
+	 *	Descriptor chains (card relative)
+	 */
+	 
+	lp->tx_chain 		= lp->exec_box->data[8];   /* Transmit list start offset */
+	lp->rx_chain 		= lp->exec_box->data[10];  /* Receive list start offset */
+	lp->tx_len 		= lp->exec_box->data[9];   /* Transmit list count */ 
+	lp->rx_len 		= lp->exec_box->data[11];  /* Receive list count */
+
+	init_MUTEX_LOCKED(&lp->cmd_mutex);
+	init_completion(&lp->execution_cmd);
+	init_completion(&lp->xceiver_cmd);
+	
+	printk("%s: Firmware Rev %d. %d RX buffers, %d TX buffers. Base of 0x%08X.\n",
+		dev->name, lp->exec_box->data[12], lp->rx_len, lp->tx_len, lp->base);
+
+	dev->open		= mc32_open;
+	dev->stop		= mc32_close;
+	dev->hard_start_xmit	= mc32_send_packet;
+	dev->get_stats		= mc32_get_stats;
+	dev->set_multicast_list = mc32_set_multicast_list;
+	dev->tx_timeout		= mc32_timeout;
+	dev->watchdog_timeo	= HZ*5;	/* Board does all the work */
+	dev->ethtool_ops	= &netdev_ethtool_ops;
+
+	return 0;
+
+err_exit_irq:
+	free_irq(dev->irq, dev);
+err_exit_ports:
+	release_region(dev->base_addr, MC32_IO_EXTENT);
+	return err;
+}
+
+
+/**
+ *	mc32_ready_poll		-	wait until we can feed it a command
+ *	@dev:	The device to wait for
+ *	
+ *	Wait until the card becomes ready to accept a command via the
+ *	command register. This tells us nothing about the completion
+ *	status of any pending commands and takes very little time at all.
+ */
+ 
+static inline void mc32_ready_poll(struct net_device *dev)
+{
+	int ioaddr = dev->base_addr;
+	while(!(inb(ioaddr+HOST_STATUS)&HOST_STATUS_CRR));
+}
+
+
+/**
+ *	mc32_command_nowait	-	send a command non blocking
+ *	@dev: The 3c527 to issue the command to
+ *	@cmd: The command word to write to the mailbox
+ *	@data: A data block if the command expects one
+ *	@len: Length of the data block
+ *
+ *	Send a command from interrupt state. If there is a command
+ *	currently being executed then we return an error of -1. It
+ *	simply isn't viable to wait around as commands may be
+ *	slow. This can theoretically be starved on SMP, but it's hard
+ *	to see a realistic situation.  We do not wait for the command
+ *	to complete --- we rely on the interrupt handler to tidy up
+ *	after us.
+ */
+
+static int mc32_command_nowait(struct net_device *dev, u16 cmd, void *data, int len)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+	int ret = -1;
+
+	if (down_trylock(&lp->cmd_mutex) == 0)
+	{
+		lp->cmd_nonblocking=1;
+		lp->exec_box->mbox=0;
+		lp->exec_box->mbox=cmd;
+		memcpy((void *)lp->exec_box->data, data, len);
+		barrier();	/* the memcpy forgot the volatile so be sure */
+
+		/* Send the command */
+		mc32_ready_poll(dev);
+		outb(1<<6, ioaddr+HOST_CMD);
+
+		ret = 0;
+
+		/* Interrupt handler will signal mutex on completion */
+	}
+
+	return ret;
+}
+
+
+/**
+ *	mc32_command	-	send a command and sleep until completion
+ *	@dev: The 3c527 card to issue the command to
+ *	@cmd: The command word to write to the mailbox
+ *	@data: A data block if the command expects one
+ *	@len: Length of the data block
+ *
+ *	Sends exec commands in a user context. This permits us to wait around
+ *	for the replies and also to wait for the command buffer to complete
+ *	from a previous command before we execute our command. After our 
+ *	command completes we will attempt any pending multicast reload
+ *	we blocked off by hogging the exec buffer.
+ *
+ *	You feed the card a command, you wait, it interrupts you get a 
+ *	reply. All well and good. The complication arises because you use
+ *	commands for filter list changes which come in at bh level from things
+ *	like IPV6 group stuff.
+ */
+  
+static int mc32_command(struct net_device *dev, u16 cmd, void *data, int len)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+	int ret = 0;
+	
+	down(&lp->cmd_mutex);
+
+	/*
+	 *     My Turn
+	 */
+
+	lp->cmd_nonblocking=0;
+	lp->exec_box->mbox=0;
+	lp->exec_box->mbox=cmd;
+	memcpy((void *)lp->exec_box->data, data, len);
+	barrier();	/* the memcpy forgot the volatile so be sure */
+
+	mc32_ready_poll(dev);
+	outb(1<<6, ioaddr+HOST_CMD);
+
+	wait_for_completion(&lp->execution_cmd);
+	
+	if(lp->exec_box->mbox&(1<<13))
+		ret = -1;
+
+	up(&lp->cmd_mutex);
+
+	/*
+	 *	A multicast set got blocked - try it now
+         */
+
+	if(lp->mc_reload_wait)
+	{
+		mc32_reset_multicast_list(dev);
+	}
+
+	return ret;
+}
+
+
+/**
+ *	mc32_start_transceiver	-	tell board to restart tx/rx
+ *	@dev: The 3c527 card to issue the command to
+ *
+ *	This may be called from the interrupt state, where it is used
+ *	to restart the rx ring if the card runs out of rx buffers. 
+ *	
+ * 	We must first check if it's ok to (re)start the transceiver. See
+ *      mc32_close for details.
+ */
+
+static void mc32_start_transceiver(struct net_device *dev) {
+
+	struct mc32_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+
+	/* Ignore RX overflow on device closure */ 
+	if (lp->xceiver_desired_state==HALTED)
+		return; 
+
+	/* Give the card the offset to the post-EOL-bit RX descriptor */
+	mc32_ready_poll(dev); 
+	lp->rx_box->mbox=0;
+	lp->rx_box->data[0]=lp->rx_ring[prev_rx(lp->rx_ring_tail)].p->next; 
+	outb(HOST_CMD_START_RX, ioaddr+HOST_CMD);      
+
+	mc32_ready_poll(dev); 
+	lp->tx_box->mbox=0;
+	outb(HOST_CMD_RESTRT_TX, ioaddr+HOST_CMD);   /* card ignores this on RX restart */ 
+	
+	/* We are not interrupted on start completion */ 
+}
+
+
+/**
+ *	mc32_halt_transceiver	-	tell board to stop tx/rx
+ *	@dev: The 3c527 card to issue the command to
+ *
+ *	We issue the commands to halt the card's transceiver. In fact,
+ *	after some experimenting we now simply tell the card to
+ *	suspend. When issuing aborts occasionally odd things happened.
+ *
+ *	We then sleep until the card has notified us that both rx and
+ *	tx have been suspended.
+ */ 
+
+static void mc32_halt_transceiver(struct net_device *dev) 
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int ioaddr = dev->base_addr;
+
+	mc32_ready_poll(dev);	
+	lp->rx_box->mbox=0;
+	outb(HOST_CMD_SUSPND_RX, ioaddr+HOST_CMD);			
+	wait_for_completion(&lp->xceiver_cmd);
+
+	mc32_ready_poll(dev); 
+	lp->tx_box->mbox=0;
+	outb(HOST_CMD_SUSPND_TX, ioaddr+HOST_CMD);	
+	wait_for_completion(&lp->xceiver_cmd);
+}
+
+
+/**
+ *	mc32_load_rx_ring	-	load the ring of receive buffers
+ *	@dev: 3c527 to build the ring for
+ *
+ *	This initalises the on-card and driver datastructures to
+ *	the point where mc32_start_transceiver() can be called.
+ *
+ *	The card sets up the receive ring for us. We are required to use the
+ *	ring it provides, although the size of the ring is configurable.
+ *
+ * 	We allocate an sk_buff for each ring entry in turn and
+ * 	initalise its house-keeping info. At the same time, we read
+ * 	each 'next' pointer in our rx_ring array. This reduces slow
+ * 	shared-memory reads and makes it easy to access predecessor
+ * 	descriptors.
+ *
+ *	We then set the end-of-list bit for the last entry so that the
+ * 	card will know when it has run out of buffers.
+ */
+	 
+static int mc32_load_rx_ring(struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int i;
+	u16 rx_base;
+	volatile struct skb_header *p;
+	
+	rx_base=lp->rx_chain;
+
+	for(i=0; i<RX_RING_LEN; i++) {
+		lp->rx_ring[i].skb=alloc_skb(1532, GFP_KERNEL);
+		if (lp->rx_ring[i].skb==NULL) {
+			for (;i>=0;i--)
+				kfree_skb(lp->rx_ring[i].skb);
+			return -ENOBUFS;
+		}
+		skb_reserve(lp->rx_ring[i].skb, 18);
+
+		p=isa_bus_to_virt(lp->base+rx_base);
+				
+		p->control=0;
+		p->data=isa_virt_to_bus(lp->rx_ring[i].skb->data);
+		p->status=0;
+		p->length=1532;
+	
+		lp->rx_ring[i].p=p; 
+		rx_base=p->next; 
+	}
+
+	lp->rx_ring[i-1].p->control |= CONTROL_EOL;
+
+	lp->rx_ring_tail=0;
+
+	return 0;
+}	
+
+
+/**
+ *	mc32_flush_rx_ring	-	free the ring of receive buffers
+ *	@lp: Local data of 3c527 to flush the rx ring of
+ *
+ *	Free the buffer for each ring slot. This may be called 
+ *      before mc32_load_rx_ring(), eg. on error in mc32_open().
+ *      Requires rx skb pointers to point to a valid skb, or NULL.
+ */
+
+static void mc32_flush_rx_ring(struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int i; 
+
+	for(i=0; i < RX_RING_LEN; i++) 
+	{ 
+		if (lp->rx_ring[i].skb) {
+			dev_kfree_skb(lp->rx_ring[i].skb);
+			lp->rx_ring[i].skb = NULL;
+		}
+		lp->rx_ring[i].p=NULL; 
+	} 
+}
+
+
+/**
+ *	mc32_load_tx_ring	-	load transmit ring
+ *	@dev: The 3c527 card to issue the command to
+ *
+ *	This sets up the host transmit data-structures. 
+ *
+ *	First, we obtain from the card it's current postion in the tx
+ *	ring, so that we will know where to begin transmitting
+ *	packets.
+ * 	
+ * 	Then, we read the 'next' pointers from the on-card tx ring into
+ *  	our tx_ring array to reduce slow shared-mem reads. Finally, we
+ * 	intitalise the tx house keeping variables.
+ * 
+ */ 
+
+static void mc32_load_tx_ring(struct net_device *dev)
+{ 
+	struct mc32_local *lp = netdev_priv(dev);
+	volatile struct skb_header *p;
+	int i; 
+	u16 tx_base;
+
+	tx_base=lp->tx_box->data[0]; 
+
+	for(i=0 ; i<TX_RING_LEN ; i++)
+	{
+		p=isa_bus_to_virt(lp->base+tx_base);
+		lp->tx_ring[i].p=p; 
+		lp->tx_ring[i].skb=NULL;
+
+		tx_base=p->next;
+	}
+
+	/* -1 so that tx_ring_head cannot "lap" tx_ring_tail */
+	/* see mc32_tx_ring */
+
+	atomic_set(&lp->tx_count, TX_RING_LEN-1); 
+	atomic_set(&lp->tx_ring_head, 0); 
+	lp->tx_ring_tail=0; 
+} 
+
+
+/**
+ *	mc32_flush_tx_ring 	-	free transmit ring
+ *	@lp: Local data of 3c527 to flush the tx ring of
+ *
+ *      If the ring is non-empty, zip over the it, freeing any
+ *      allocated skb_buffs.  The tx ring house-keeping variables are
+ *      then reset. Requires rx skb pointers to point to a valid skb,
+ *      or NULL.
+ */
+
+static void mc32_flush_tx_ring(struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	int i;
+
+	for (i=0; i < TX_RING_LEN; i++)
+	{
+		if (lp->tx_ring[i].skb)
+		{
+			dev_kfree_skb(lp->tx_ring[i].skb);
+			lp->tx_ring[i].skb = NULL;
+		}
+	}
+
+	atomic_set(&lp->tx_count, 0); 
+	atomic_set(&lp->tx_ring_head, 0); 
+	lp->tx_ring_tail=0;
+}
+ 	
+
+/**
+ *	mc32_open	-	handle 'up' of card
+ *	@dev: device to open
+ *
+ *	The user is trying to bring the card into ready state. This requires
+ *	a brief dialogue with the card. Firstly we enable interrupts and then
+ *	'indications'. Without these enabled the card doesn't bother telling
+ *	us what it has done. This had me puzzled for a week.
+ *
+ *	We configure the number of card descriptors, then load the network
+ *	address and multicast filters. Turn on the workaround mode. This
+ *	works around a bug in the 82586 - it asks the firmware to do
+ *	so. It has a performance (latency) hit but is needed on busy
+ *	[read most] lans. We load the ring with buffers then we kick it
+ *	all off.
+ */
+
+static int mc32_open(struct net_device *dev)
+{
+	int ioaddr = dev->base_addr;
+	struct mc32_local *lp = netdev_priv(dev);
+	u8 one=1;
+	u8 regs;
+	u16 descnumbuffs[2] = {TX_RING_LEN, RX_RING_LEN};
+
+	/*
+	 *	Interrupts enabled
+	 */
+
+	regs=inb(ioaddr+HOST_CTRL);
+	regs|=HOST_CTRL_INTE;
+	outb(regs, ioaddr+HOST_CTRL);
+	
+	/*
+	 *      Allow ourselves to issue commands
+	 */
+
+	up(&lp->cmd_mutex);
+
+
+	/*
+	 *	Send the indications on command
+	 */
+
+	mc32_command(dev, 4, &one, 2);
+
+	/*
+	 *	Poke it to make sure it's really dead. 
+	 */
+
+	mc32_halt_transceiver(dev); 
+	mc32_flush_tx_ring(dev); 
+
+	/* 
+	 *	Ask card to set up on-card descriptors to our spec 
+	 */ 
+
+	if(mc32_command(dev, 8, descnumbuffs, 4)) { 
+		printk("%s: %s rejected our buffer configuration!\n",
+	 	       dev->name, cardname);
+		mc32_close(dev); 
+		return -ENOBUFS; 
+	}
+	
+	/* Report new configuration */ 
+	mc32_command(dev, 6, NULL, 0); 
+
+	lp->tx_chain 		= lp->exec_box->data[8];   /* Transmit list start offset */
+	lp->rx_chain 		= lp->exec_box->data[10];  /* Receive list start offset */
+	lp->tx_len 		= lp->exec_box->data[9];   /* Transmit list count */ 
+	lp->rx_len 		= lp->exec_box->data[11];  /* Receive list count */
+ 
+	/* Set Network Address */
+	mc32_command(dev, 1, dev->dev_addr, 6);
+	
+	/* Set the filters */
+	mc32_set_multicast_list(dev);
+		   
+	if (WORKAROUND_82586) { 
+		u16 zero_word=0;
+		mc32_command(dev, 0x0D, &zero_word, 2);   /* 82586 bug workaround on  */
+	}
+
+	mc32_load_tx_ring(dev);
+	
+	if(mc32_load_rx_ring(dev)) 
+	{
+		mc32_close(dev);
+		return -ENOBUFS;
+	}
+
+	lp->xceiver_desired_state = RUNNING;
+	
+	/* And finally, set the ball rolling... */
+	mc32_start_transceiver(dev);
+
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+
+/**
+ *	mc32_timeout	-	handle a timeout from the network layer
+ *	@dev: 3c527 that timed out
+ *
+ *	Handle a timeout on transmit from the 3c527. This normally means
+ *	bad things as the hardware handles cable timeouts and mess for
+ *	us.
+ *
+ */
+
+static void mc32_timeout(struct net_device *dev)
+{
+	printk(KERN_WARNING "%s: transmit timed out?\n", dev->name);
+	/* Try to restart the adaptor. */
+	netif_wake_queue(dev);
+}
+
+
+/**
+ *	mc32_send_packet	-	queue a frame for transmit
+ *	@skb: buffer to transmit
+ *	@dev: 3c527 to send it out of
+ *
+ *	Transmit a buffer. This normally means throwing the buffer onto
+ *	the transmit queue as the queue is quite large. If the queue is
+ *	full then we set tx_busy and return. Once the interrupt handler
+ *	gets messages telling it to reclaim transmit queue entries, we will
+ *	clear tx_busy and the kernel will start calling this again.
+ *
+ *      We do not disable interrupts or acquire any locks; this can
+ *      run concurrently with mc32_tx_ring(), and the function itself
+ *      is serialised at a higher layer. However, similarly for the
+ *      card itself, we must ensure that we update tx_ring_head only
+ *      after we've established a valid packet on the tx ring (and
+ *      before we let the card "see" it, to prevent it racing with the
+ *      irq handler).
+ * 
+ */
+
+static int mc32_send_packet(struct sk_buff *skb, struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	u32 head = atomic_read(&lp->tx_ring_head);
+	
+	volatile struct skb_header *p, *np;
+
+	netif_stop_queue(dev);
+
+	if(atomic_read(&lp->tx_count)==0) {
+		return 1;
+	}
+
+	skb = skb_padto(skb, ETH_ZLEN);
+	if (skb == NULL) {
+		netif_wake_queue(dev);
+		return 0;
+	}
+
+	atomic_dec(&lp->tx_count); 
+
+	/* P is the last sending/sent buffer as a pointer */
+	p=lp->tx_ring[head].p;
+		
+	head = next_tx(head);
+
+	/* NP is the buffer we will be loading */
+	np=lp->tx_ring[head].p; 
+	
+	/* We will need this to flush the buffer out */
+	lp->tx_ring[head].skb=skb;
+
+	np->length      = unlikely(skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;			
+	np->data	= isa_virt_to_bus(skb->data);
+	np->status	= 0;
+	np->control     = CONTROL_EOP | CONTROL_EOL;     
+	wmb();
+		
+	/*
+	 * The new frame has been setup; we can now
+	 * let the interrupt handler and card "see" it
+	 */
+
+	atomic_set(&lp->tx_ring_head, head); 
+	p->control     &= ~CONTROL_EOL;
+
+	netif_wake_queue(dev);
+	return 0;
+}
+
+
+/**
+ *	mc32_update_stats	-	pull off the on board statistics
+ *	@dev: 3c527 to service
+ *
+ * 
+ *	Query and reset the on-card stats. There's the small possibility
+ *	of a race here, which would result in an underestimation of
+ *	actual errors. As such, we'd prefer to keep all our stats
+ *	collection in software. As a rule, we do. However it can't be
+ *	used for rx errors and collisions as, by default, the card discards
+ *	bad rx packets. 
+ *
+ *	Setting the SAV BP in the rx filter command supposedly
+ *	stops this behaviour. However, testing shows that it only seems to
+ *	enable the collation of on-card rx statistics --- the driver
+ *	never sees an RX descriptor with an error status set.
+ *
+ */
+
+static void mc32_update_stats(struct net_device *dev)
+{
+	struct mc32_local *lp = netdev_priv(dev);
+	volatile struct mc32_stats *st = lp->stats; 
+
+	u32 rx_errors=0; 
+      
+	rx_errors+=lp->net_stats.rx_crc_errors   +=st->rx_crc_errors;         
+	                                           st->rx_crc_errors=0;
+	rx_errors+=lp->net_stats.rx_fifo_errors  +=st->rx_overrun_errors;   
+	                                           st->rx_overrun_errors=0; 
+	rx_errors+=lp->net_stats.rx_frame_errors +=st->rx_alignment_errors; 
+ 	                                           st->rx_alignment_errors=0;
+	rx_errors+=lp->net_stats.rx_length_errors+=st->rx_tooshort_errors; 
+	                                           st->rx_tooshort_errors=0;
+	rx_errors+=lp->net_stats.rx_missed_errors+=st->rx_outofresource_errors;
+	                                           st->rx_outofresource_errors=0; 
+        lp->net_stats.rx_errors=rx_errors; 
+						   
+	/* Number of packets which saw one collision */
+	lp->net_stats.collisions+=st->dataC[10];
+	st->dataC[10]=0; 
+
+	/* Number of packets which saw 2--15 collisions */ 
+	lp->net_stats.collisions+=st->dataC[11]; 
+	st->dataC[11]=0; 
+}	
+
+
+/**
+ *	mc32_rx_ring	-	process the receive ring
+ *	@dev: 3c527 that needs its receive ring processing
+ *
+ *
+ *	We have received one or more indications from the card that a
+ *	receive has completed. The buffer ring thus contains dirty
+ *	entries. We walk the ring by iterating over the circular rx_ring
+ *	array, starting at the next dirty buffer (which happens to be the
+ *	one we finished up at last time around).
+ *
+ *	For each completed packet, we will either copy it and pass it up
+ * 	the stack or, if the packet is near MTU sized, we allocate
+ *	another buffer and flip the old one up the stack.
+ * 
+ *	We must succeed in keeping a buffer on the ring. If necessary we
+ *	will toss a received packet rather than lose a ring entry. Once
+ *	the first uncompleted descriptor is found, we move the
+ *	End-Of-List bit to include the buffers