900 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			900 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* 3c501.c: A 3Com 3c501 Ethernet driver for Linux. */
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/*
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    Written 1992,1993,1994  Donald Becker
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    Copyright 1993 United States Government as represented by the
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    Director, National Security Agency.  This software may be used and
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    distributed according to the terms of the GNU General Public License,
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    incorporated herein by reference.
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    This is a device driver for the 3Com Etherlink 3c501.
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    Do not purchase this card, even as a joke.  It's performance is horrible,
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    and it breaks in many ways.
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    The original author may be reached as becker@scyld.com, or C/O
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	Scyld Computing Corporation
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	410 Severn Ave., Suite 210
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	Annapolis MD 21403
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    Fixed (again!) the missing interrupt locking on TX/RX shifting.
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	Alan Cox <alan@lxorguk.ukuu.org.uk>
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    Removed calls to init_etherdev since they are no longer needed, and
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    cleaned up modularization just a bit. The driver still allows only
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    the default address for cards when loaded as a module, but that's
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    really less braindead than anyone using a 3c501 board. :)
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		    19950208 (invid@msen.com)
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    Added traps for interrupts hitting the window as we clear and TX load
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    the board. Now getting 150K/second FTP with a 3c501 card. Still playing
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    with a TX-TX optimisation to see if we can touch 180-200K/second as seems
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    theoretically maximum.
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		19950402 Alan Cox <alan@lxorguk.ukuu.org.uk>
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    Cleaned up for 2.3.x because we broke SMP now.
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		20000208 Alan Cox <alan@lxorguk.ukuu.org.uk>
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    Check up pass for 2.5. Nothing significant changed
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		20021009 Alan Cox <alan@lxorguk.ukuu.org.uk>
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    Fixed zero fill corner case
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		20030104 Alan Cox <alan@lxorguk.ukuu.org.uk>
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   For the avoidance of doubt the "preferred form" of this code is one which
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   is in an open non patent encumbered format. Where cryptographic key signing
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   forms part of the process of creating an executable the information
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   including keys needed to generate an equivalently functional executable
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   are deemed to be part of the source code.
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*/
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/**
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 * DOC: 3c501 Card Notes
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 *
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 *  Some notes on this thing if you have to hack it.  [Alan]
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 *
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 *  Some documentation is available from 3Com. Due to the boards age
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 *  standard responses when you ask for this will range from 'be serious'
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 *  to 'give it to a museum'. The documentation is incomplete and mostly
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 *  of historical interest anyway.
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 *
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 *  The basic system is a single buffer which can be used to receive or
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 *  transmit a packet. A third command mode exists when you are setting
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 *  things up.
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 *
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 *  If it's transmitting it's not receiving and vice versa. In fact the
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 *  time to get the board back into useful state after an operation is
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 *  quite large.
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 *
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 *  The driver works by keeping the board in receive mode waiting for a
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 *  packet to arrive. When one arrives it is copied out of the buffer
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 *  and delivered to the kernel. The card is reloaded and off we go.
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 *
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 *  When transmitting lp->txing is set and the card is reset (from
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 *  receive mode) [possibly losing a packet just received] to command
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 *  mode. A packet is loaded and transmit mode triggered. The interrupt
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 *  handler runs different code for transmit interrupts and can handle
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 *  returning to receive mode or retransmissions (yes you have to help
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 *  out with those too).
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 *
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 * DOC: Problems
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 *
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 *  There are a wide variety of undocumented error returns from the card
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 *  and you basically have to kick the board and pray if they turn up. Most
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 *  only occur under extreme load or if you do something the board doesn't
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 *  like (eg touching a register at the wrong time).
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 *
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 *  The driver is less efficient than it could be. It switches through
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 *  receive mode even if more transmits are queued. If this worries you buy
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 *  a real Ethernet card.
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 *
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 *  The combination of slow receive restart and no real multicast
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 *  filter makes the board unusable with a kernel compiled for IP
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 *  multicasting in a real multicast environment. That's down to the board,
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 *  but even with no multicast programs running a multicast IP kernel is
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 *  in group 224.0.0.1 and you will therefore be listening to all multicasts.
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 *  One nv conference running over that Ethernet and you can give up.
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 *
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 */
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#define DRV_NAME	"3c501"
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#define DRV_VERSION	"2002/10/09"
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static const char version[] =
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	DRV_NAME ".c: " DRV_VERSION " Alan Cox (alan@lxorguk.ukuu.org.uk).\n";
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/*
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 *	Braindamage remaining:
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 *	The 3c501 board.
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 */
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/fcntl.h>
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#include <linux/ioport.h>
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#include <linux/interrupt.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <linux/spinlock.h>
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#include <linux/ethtool.h>
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#include <linux/delay.h>
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#include <linux/bitops.h>
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#include <asm/uaccess.h>
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#include <asm/io.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/skbuff.h>
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#include <linux/init.h>
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#include "3c501.h"
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/*
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 *	The boilerplate probe code.
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 */
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static int io = 0x280;
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static int irq = 5;
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static int mem_start;
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/**
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 * el1_probe:		-	probe for a 3c501
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 * @dev: The device structure passed in to probe.
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 *
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 * This can be called from two places. The network layer will probe using
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 * a device structure passed in with the probe information completed. For a
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 * modular driver we use #init_module to fill in our own structure and probe
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 * for it.
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 *
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 * Returns 0 on success. ENXIO if asked not to probe and ENODEV if asked to
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 * probe and failing to find anything.
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 */
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struct net_device * __init el1_probe(int unit)
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{
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	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
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	static unsigned ports[] = { 0x280, 0x300, 0};
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	unsigned *port;
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	int err = 0;
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	if (!dev)
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		return ERR_PTR(-ENOMEM);
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	if (unit >= 0) {
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		sprintf(dev->name, "eth%d", unit);
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		netdev_boot_setup_check(dev);
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		io = dev->base_addr;
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		irq = dev->irq;
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		mem_start = dev->mem_start & 7;
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	}
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	if (io > 0x1ff) {	/* Check a single specified location. */
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		err = el1_probe1(dev, io);
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	} else if (io != 0) {
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		err = -ENXIO;		/* Don't probe at all. */
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	} else {
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		for (port = ports; *port && el1_probe1(dev, *port); port++)
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			;
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		if (!*port)
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			err = -ENODEV;
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	}
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	if (err)
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		goto out;
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	err = register_netdev(dev);
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	if (err)
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		goto out1;
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	return dev;
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out1:
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	release_region(dev->base_addr, EL1_IO_EXTENT);
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out:
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	free_netdev(dev);
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	return ERR_PTR(err);
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}
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static const struct net_device_ops el_netdev_ops = {
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	.ndo_open		= el_open,
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	.ndo_stop		= el1_close,
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	.ndo_start_xmit 	= el_start_xmit,
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	.ndo_tx_timeout		= el_timeout,
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	.ndo_set_multicast_list = set_multicast_list,
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	.ndo_change_mtu		= eth_change_mtu,
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	.ndo_set_mac_address 	= eth_mac_addr,
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	.ndo_validate_addr	= eth_validate_addr,
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};
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/**
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 *	el1_probe1:
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 *	@dev: The device structure to use
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 *	@ioaddr: An I/O address to probe at.
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 *
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 *	The actual probe. This is iterated over by #el1_probe in order to
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 *	check all the applicable device locations.
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 *
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 *	Returns 0 for a success, in which case the device is activated,
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 *	EAGAIN if the IRQ is in use by another driver, and ENODEV if the
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 *	board cannot be found.
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 */
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static int __init el1_probe1(struct net_device *dev, int ioaddr)
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{
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	struct net_local *lp;
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	const char *mname;		/* Vendor name */
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	unsigned char station_addr[6];
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	int autoirq = 0;
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	int i;
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	/*
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	 *	Reserve I/O resource for exclusive use by this driver
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	 */
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	if (!request_region(ioaddr, EL1_IO_EXTENT, DRV_NAME))
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		return -ENODEV;
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	/*
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	 *	Read the station address PROM data from the special port.
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	 */
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	for (i = 0; i < 6; i++) {
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		outw(i, ioaddr + EL1_DATAPTR);
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		station_addr[i] = inb(ioaddr + EL1_SAPROM);
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	}
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	/*
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	 *	Check the first three octets of the S.A. for 3Com's prefix, or
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	 *	for the Sager NP943 prefix.
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	 */
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	if (station_addr[0] == 0x02  &&  station_addr[1] == 0x60
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						&& station_addr[2] == 0x8c)
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		mname = "3c501";
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	else if (station_addr[0] == 0x00  &&  station_addr[1] == 0x80
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						&& station_addr[2] == 0xC8)
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		mname = "NP943";
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	else {
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		release_region(ioaddr, EL1_IO_EXTENT);
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		return -ENODEV;
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	}
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	/*
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	 *	We auto-IRQ by shutting off the interrupt line and letting it
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	 *	float high.
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	 */
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	dev->irq = irq;
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	if (dev->irq < 2) {
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		unsigned long irq_mask;
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		irq_mask = probe_irq_on();
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		inb(RX_STATUS);		/* Clear pending interrupts. */
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		inb(TX_STATUS);
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		outb(AX_LOOP + 1, AX_CMD);
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		outb(0x00, AX_CMD);
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		mdelay(20);
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		autoirq = probe_irq_off(irq_mask);
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		if (autoirq == 0) {
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			pr_warning("%s probe at %#x failed to detect IRQ line.\n",
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				mname, ioaddr);
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			release_region(ioaddr, EL1_IO_EXTENT);
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			return -EAGAIN;
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		}
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	}
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	outb(AX_RESET+AX_LOOP, AX_CMD);			/* Loopback mode. */
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	dev->base_addr = ioaddr;
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	memcpy(dev->dev_addr, station_addr, ETH_ALEN);
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	if (mem_start & 0xf)
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		el_debug = mem_start & 0x7;
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	if (autoirq)
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		dev->irq = autoirq;
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	pr_info("%s: %s EtherLink at %#lx, using %sIRQ %d.\n",
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			dev->name, mname, dev->base_addr,
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			autoirq ? "auto":"assigned ", dev->irq);
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#ifdef CONFIG_IP_MULTICAST
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	pr_warning("WARNING: Use of the 3c501 in a multicast kernel is NOT recommended.\n");
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#endif
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	if (el_debug)
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		pr_debug("%s", version);
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	lp = netdev_priv(dev);
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	memset(lp, 0, sizeof(struct net_local));
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	spin_lock_init(&lp->lock);
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	/*
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	 *	The EL1-specific entries in the device structure.
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	 */
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	dev->netdev_ops = &el_netdev_ops;
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	dev->watchdog_timeo = HZ;
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	dev->ethtool_ops = &netdev_ethtool_ops;
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	return 0;
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}
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/**
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 *	el1_open:
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 *	@dev: device that is being opened
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 *
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 *	When an ifconfig is issued which changes the device flags to include
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 *	IFF_UP this function is called. It is only called when the change
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 *	occurs, not when the interface remains up. #el1_close will be called
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 *	when it goes down.
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 *
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 *	Returns 0 for a successful open, or -EAGAIN if someone has run off
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 *	with our interrupt line.
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 */
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static int el_open(struct net_device *dev)
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{
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	int retval;
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	int ioaddr = dev->base_addr;
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	struct net_local *lp = netdev_priv(dev);
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	unsigned long flags;
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	if (el_debug > 2)
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		pr_debug("%s: Doing el_open()...\n", dev->name);
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	retval = request_irq(dev->irq, &el_interrupt, 0, dev->name, dev);
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	if (retval)
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		return retval;
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	spin_lock_irqsave(&lp->lock, flags);
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	el_reset(dev);
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	spin_unlock_irqrestore(&lp->lock, flags);
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	lp->txing = 0;		/* Board in RX mode */
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	outb(AX_RX, AX_CMD);	/* Aux control, irq and receive enabled */
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	netif_start_queue(dev);
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	return 0;
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}
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 | 
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/**
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 * el_timeout:
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 * @dev: The 3c501 card that has timed out
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 *
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 * Attempt to restart the board. This is basically a mixture of extreme
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 * violence and prayer
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 *
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 */
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static void el_timeout(struct net_device *dev)
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{
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	struct net_local *lp = netdev_priv(dev);
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	int ioaddr = dev->base_addr;
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	if (el_debug)
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		pr_debug("%s: transmit timed out, txsr %#2x axsr=%02x rxsr=%02x.\n",
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			dev->name, inb(TX_STATUS),
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			inb(AX_STATUS), inb(RX_STATUS));
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	dev->stats.tx_errors++;
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	outb(TX_NORM, TX_CMD);
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	outb(RX_NORM, RX_CMD);
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	outb(AX_OFF, AX_CMD);	/* Just trigger a false interrupt. */
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	outb(AX_RX, AX_CMD);	/* Aux control, irq and receive enabled */
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	lp->txing = 0;		/* Ripped back in to RX */
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	netif_wake_queue(dev);
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}
 | 
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 | 
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 | 
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/**
 | 
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 * el_start_xmit:
 | 
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 * @skb: The packet that is queued to be sent
 | 
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 * @dev: The 3c501 card we want to throw it down
 | 
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 *
 | 
						|
 * Attempt to send a packet to a 3c501 card. There are some interesting
 | 
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 * catches here because the 3c501 is an extremely old and therefore
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 * stupid piece of technology.
 | 
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 *
 | 
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 * If we are handling an interrupt on the other CPU we cannot load a packet
 | 
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 * as we may still be attempting to retrieve the last RX packet buffer.
 | 
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 *
 | 
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 * When a transmit times out we dump the card into control mode and just
 | 
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 * start again. It happens enough that it isnt worth logging.
 | 
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 *
 | 
						|
 * We avoid holding the spin locks when doing the packet load to the board.
 | 
						|
 * The device is very slow, and its DMA mode is even slower. If we held the
 | 
						|
 * lock while loading 1500 bytes onto the controller we would drop a lot of
 | 
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 * serial port characters. This requires we do extra locking, but we have
 | 
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 * no real choice.
 | 
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 */
 | 
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 | 
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static netdev_tx_t el_start_xmit(struct sk_buff *skb, struct net_device *dev)
 | 
						|
{
 | 
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	struct net_local *lp = netdev_priv(dev);
 | 
						|
	int ioaddr = dev->base_addr;
 | 
						|
	unsigned long flags;
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Avoid incoming interrupts between us flipping txing and flipping
 | 
						|
	 *	mode as the driver assumes txing is a faithful indicator of card
 | 
						|
	 *	state
 | 
						|
	 */
 | 
						|
 | 
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	spin_lock_irqsave(&lp->lock, flags);
 | 
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 | 
						|
	/*
 | 
						|
	 *	Avoid timer-based retransmission conflicts.
 | 
						|
	 */
 | 
						|
 | 
						|
	netif_stop_queue(dev);
 | 
						|
 | 
						|
	do {
 | 
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		int len = skb->len;
 | 
						|
		int pad = 0;
 | 
						|
		int gp_start;
 | 
						|
		unsigned char *buf = skb->data;
 | 
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 | 
						|
		if (len < ETH_ZLEN)
 | 
						|
			pad = ETH_ZLEN - len;
 | 
						|
 | 
						|
		gp_start = 0x800 - (len + pad);
 | 
						|
 | 
						|
		lp->tx_pkt_start = gp_start;
 | 
						|
		lp->collisions = 0;
 | 
						|
 | 
						|
		dev->stats.tx_bytes += skb->len;
 | 
						|
 | 
						|
		/*
 | 
						|
		 *	Command mode with status cleared should [in theory]
 | 
						|
		 *	mean no more interrupts can be pending on the card.
 | 
						|
		 */
 | 
						|
 | 
						|
		outb_p(AX_SYS, AX_CMD);
 | 
						|
		inb_p(RX_STATUS);
 | 
						|
		inb_p(TX_STATUS);
 | 
						|
 | 
						|
		lp->loading = 1;
 | 
						|
		lp->txing = 1;
 | 
						|
 | 
						|
		/*
 | 
						|
		 *	Turn interrupts back on while we spend a pleasant
 | 
						|
		 *	afternoon loading bytes into the board
 | 
						|
		 */
 | 
						|
 | 
						|
		spin_unlock_irqrestore(&lp->lock, flags);
 | 
						|
 | 
						|
		/* Set rx packet area to 0. */
 | 
						|
		outw(0x00, RX_BUF_CLR);
 | 
						|
		/* aim - packet will be loaded into buffer start */
 | 
						|
		outw(gp_start, GP_LOW);
 | 
						|
		/* load buffer (usual thing each byte increments the pointer) */
 | 
						|
		outsb(DATAPORT, buf, len);
 | 
						|
		if (pad) {
 | 
						|
			while (pad--)		/* Zero fill buffer tail */
 | 
						|
				outb(0, DATAPORT);
 | 
						|
		}
 | 
						|
		/* the board reuses the same register */
 | 
						|
		outw(gp_start, GP_LOW);
 | 
						|
 | 
						|
		if (lp->loading != 2) {
 | 
						|
			/* fire ... Trigger xmit.  */
 | 
						|
			outb(AX_XMIT, AX_CMD);
 | 
						|
			lp->loading = 0;
 | 
						|
			dev->trans_start = jiffies;
 | 
						|
			if (el_debug > 2)
 | 
						|
				pr_debug(" queued xmit.\n");
 | 
						|
			dev_kfree_skb(skb);
 | 
						|
			return NETDEV_TX_OK;
 | 
						|
		}
 | 
						|
		/* A receive upset our load, despite our best efforts */
 | 
						|
		if (el_debug > 2)
 | 
						|
			pr_debug("%s: burped during tx load.\n", dev->name);
 | 
						|
		spin_lock_irqsave(&lp->lock, flags);
 | 
						|
	} while (1);
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * el_interrupt:
 | 
						|
 * @irq: Interrupt number
 | 
						|
 * @dev_id: The 3c501 that burped
 | 
						|
 *
 | 
						|
 * Handle the ether interface interrupts. The 3c501 needs a lot more
 | 
						|
 * hand holding than most cards. In particular we get a transmit interrupt
 | 
						|
 * with a collision error because the board firmware isnt capable of rewinding
 | 
						|
 * its own transmit buffer pointers. It can however count to 16 for us.
 | 
						|
 *
 | 
						|
 * On the receive side the card is also very dumb. It has no buffering to
 | 
						|
 * speak of. We simply pull the packet out of its PIO buffer (which is slow)
 | 
						|
 * and queue it for the kernel. Then we reset the card for the next packet.
 | 
						|
 *
 | 
						|
 * We sometimes get surprise interrupts late both because the SMP IRQ delivery
 | 
						|
 * is message passing and because the card sometimes seems to deliver late. I
 | 
						|
 * think if it is part way through a receive and the mode is changed it carries
 | 
						|
 * on receiving and sends us an interrupt. We have to band aid all these cases
 | 
						|
 * to get a sensible 150kBytes/second performance. Even then you want a small
 | 
						|
 * TCP window.
 | 
						|
 */
 | 
						|
 | 
						|
static irqreturn_t el_interrupt(int irq, void *dev_id)
 | 
						|
{
 | 
						|
	struct net_device *dev = dev_id;
 | 
						|
	struct net_local *lp;
 | 
						|
	int ioaddr;
 | 
						|
	int axsr;			/* Aux. status reg. */
 | 
						|
 | 
						|
	ioaddr = dev->base_addr;
 | 
						|
	lp = netdev_priv(dev);
 | 
						|
 | 
						|
	spin_lock(&lp->lock);
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	What happened ?
 | 
						|
	 */
 | 
						|
 | 
						|
	axsr = inb(AX_STATUS);
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Log it
 | 
						|
	 */
 | 
						|
 | 
						|
	if (el_debug > 3)
 | 
						|
		pr_debug("%s: el_interrupt() aux=%#02x\n", dev->name, axsr);
 | 
						|
 | 
						|
	if (lp->loading == 1 && !lp->txing)
 | 
						|
		pr_warning("%s: Inconsistent state loading while not in tx\n",
 | 
						|
			dev->name);
 | 
						|
 | 
						|
	if (lp->txing) {
 | 
						|
		/*
 | 
						|
		 *	Board in transmit mode. May be loading. If we are
 | 
						|
		 *	loading we shouldn't have got this.
 | 
						|
		 */
 | 
						|
		int txsr = inb(TX_STATUS);
 | 
						|
 | 
						|
		if (lp->loading == 1) {
 | 
						|
			if (el_debug > 2)
 | 
						|
				pr_debug("%s: Interrupt while loading [txsr=%02x gp=%04x rp=%04x]\n",
 | 
						|
					dev->name, txsr, inw(GP_LOW), inw(RX_LOW));
 | 
						|
 | 
						|
			/* Force a reload */
 | 
						|
			lp->loading = 2;
 | 
						|
			spin_unlock(&lp->lock);
 | 
						|
			goto out;
 | 
						|
		}
 | 
						|
		if (el_debug > 6)
 | 
						|
			pr_debug("%s: txsr=%02x gp=%04x rp=%04x\n", dev->name,
 | 
						|
					txsr, inw(GP_LOW), inw(RX_LOW));
 | 
						|
 | 
						|
		if ((axsr & 0x80) && (txsr & TX_READY) == 0) {
 | 
						|
			/*
 | 
						|
			 *	FIXME: is there a logic to whether to keep
 | 
						|
			 *	on trying or reset immediately ?
 | 
						|
			 */
 | 
						|
			if (el_debug > 1)
 | 
						|
				pr_debug("%s: Unusual interrupt during Tx, txsr=%02x axsr=%02x gp=%03x rp=%03x.\n",
 | 
						|
					dev->name, txsr, axsr,
 | 
						|
					inw(ioaddr + EL1_DATAPTR),
 | 
						|
					inw(ioaddr + EL1_RXPTR));
 | 
						|
			lp->txing = 0;
 | 
						|
			netif_wake_queue(dev);
 | 
						|
		} else if (txsr & TX_16COLLISIONS) {
 | 
						|
			/*
 | 
						|
			 *	Timed out
 | 
						|
			 */
 | 
						|
			if (el_debug)
 | 
						|
				pr_debug("%s: Transmit failed 16 times, Ethernet jammed?\n", dev->name);
 | 
						|
			outb(AX_SYS, AX_CMD);
 | 
						|
			lp->txing = 0;
 | 
						|
			dev->stats.tx_aborted_errors++;
 | 
						|
			netif_wake_queue(dev);
 | 
						|
		} else if (txsr & TX_COLLISION) {
 | 
						|
			/*
 | 
						|
			 *	Retrigger xmit.
 | 
						|
			 */
 | 
						|
 | 
						|
			if (el_debug > 6)
 | 
						|
				pr_debug("%s: retransmitting after a collision.\n", dev->name);
 | 
						|
			/*
 | 
						|
			 *	Poor little chip can't reset its own start
 | 
						|
			 *	pointer
 | 
						|
			 */
 | 
						|
 | 
						|
			outb(AX_SYS, AX_CMD);
 | 
						|
			outw(lp->tx_pkt_start, GP_LOW);
 | 
						|
			outb(AX_XMIT, AX_CMD);
 | 
						|
			dev->stats.collisions++;
 | 
						|
			spin_unlock(&lp->lock);
 | 
						|
			goto out;
 | 
						|
		} else {
 | 
						|
			/*
 | 
						|
			 *	It worked.. we will now fall through and receive
 | 
						|
			 */
 | 
						|
			dev->stats.tx_packets++;
 | 
						|
			if (el_debug > 6)
 | 
						|
				pr_debug("%s: Tx succeeded %s\n", dev->name,
 | 
						|
					(txsr & TX_RDY) ? "." : "but tx is busy!");
 | 
						|
			/*
 | 
						|
			 *	This is safe the interrupt is atomic WRT itself.
 | 
						|
			 */
 | 
						|
			lp->txing = 0;
 | 
						|
			/* In case more to transmit */
 | 
						|
			netif_wake_queue(dev);
 | 
						|
		}
 | 
						|
	} else {
 | 
						|
		/*
 | 
						|
		 *	In receive mode.
 | 
						|
		 */
 | 
						|
 | 
						|
		int rxsr = inb(RX_STATUS);
 | 
						|
		if (el_debug > 5)
 | 
						|
			pr_debug("%s: rxsr=%02x txsr=%02x rp=%04x\n",
 | 
						|
				dev->name, rxsr, inb(TX_STATUS), inw(RX_LOW));
 | 
						|
		/*
 | 
						|
		 *	Just reading rx_status fixes most errors.
 | 
						|
		 */
 | 
						|
		if (rxsr & RX_MISSED)
 | 
						|
			dev->stats.rx_missed_errors++;
 | 
						|
		else if (rxsr & RX_RUNT) {
 | 
						|
			/* Handled to avoid board lock-up. */
 | 
						|
			dev->stats.rx_length_errors++;
 | 
						|
			if (el_debug > 5)
 | 
						|
				pr_debug("%s: runt.\n", dev->name);
 | 
						|
		} else if (rxsr & RX_GOOD) {
 | 
						|
			/*
 | 
						|
			 *	Receive worked.
 | 
						|
			 */
 | 
						|
			el_receive(dev);
 | 
						|
		} else {
 | 
						|
			/*
 | 
						|
			 *	Nothing?  Something is broken!
 | 
						|
			 */
 | 
						|
			if (el_debug > 2)
 | 
						|
				pr_debug("%s: No packet seen, rxsr=%02x **resetting 3c501***\n",
 | 
						|
					dev->name, rxsr);
 | 
						|
			el_reset(dev);
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Move into receive mode
 | 
						|
	 */
 | 
						|
 | 
						|
	outb(AX_RX, AX_CMD);
 | 
						|
	outw(0x00, RX_BUF_CLR);
 | 
						|
	inb(RX_STATUS);		/* Be certain that interrupts are cleared. */
 | 
						|
	inb(TX_STATUS);
 | 
						|
	spin_unlock(&lp->lock);
 | 
						|
out:
 | 
						|
	return IRQ_HANDLED;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
 * el_receive:
 | 
						|
 * @dev: Device to pull the packets from
 | 
						|
 *
 | 
						|
 * We have a good packet. Well, not really "good", just mostly not broken.
 | 
						|
 * We must check everything to see if it is good. In particular we occasionally
 | 
						|
 * get wild packet sizes from the card. If the packet seems sane we PIO it
 | 
						|
 * off the card and queue it for the protocol layers.
 | 
						|
 */
 | 
						|
 | 
						|
static void el_receive(struct net_device *dev)
 | 
						|
{
 | 
						|
	int ioaddr = dev->base_addr;
 | 
						|
	int pkt_len;
 | 
						|
	struct sk_buff *skb;
 | 
						|
 | 
						|
	pkt_len = inw(RX_LOW);
 | 
						|
 | 
						|
	if (el_debug > 4)
 | 
						|
		pr_debug(" el_receive %d.\n", pkt_len);
 | 
						|
 | 
						|
	if (pkt_len < 60 || pkt_len > 1536) {
 | 
						|
		if (el_debug)
 | 
						|
			pr_debug("%s: bogus packet, length=%d\n",
 | 
						|
						dev->name, pkt_len);
 | 
						|
		dev->stats.rx_over_errors++;
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Command mode so we can empty the buffer
 | 
						|
	 */
 | 
						|
 | 
						|
	outb(AX_SYS, AX_CMD);
 | 
						|
	skb = dev_alloc_skb(pkt_len+2);
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Start of frame
 | 
						|
	 */
 | 
						|
 | 
						|
	outw(0x00, GP_LOW);
 | 
						|
	if (skb == NULL) {
 | 
						|
		pr_info("%s: Memory squeeze, dropping packet.\n", dev->name);
 | 
						|
		dev->stats.rx_dropped++;
 | 
						|
		return;
 | 
						|
	} else {
 | 
						|
		skb_reserve(skb, 2);	/* Force 16 byte alignment */
 | 
						|
		/*
 | 
						|
		 *	The read increments through the bytes. The interrupt
 | 
						|
		 *	handler will fix the pointer when it returns to
 | 
						|
		 *	receive mode.
 | 
						|
		 */
 | 
						|
		insb(DATAPORT, skb_put(skb, pkt_len), pkt_len);
 | 
						|
		skb->protocol = eth_type_trans(skb, dev);
 | 
						|
		netif_rx(skb);
 | 
						|
		dev->stats.rx_packets++;
 | 
						|
		dev->stats.rx_bytes += pkt_len;
 | 
						|
	}
 | 
						|
	return;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * el_reset: Reset a 3c501 card
 | 
						|
 * @dev: The 3c501 card about to get zapped
 | 
						|
 *
 | 
						|
 * Even resetting a 3c501 isnt simple. When you activate reset it loses all
 | 
						|
 * its configuration. You must hold the lock when doing this. The function
 | 
						|
 * cannot take the lock itself as it is callable from the irq handler.
 | 
						|
 */
 | 
						|
 | 
						|
static void  el_reset(struct net_device *dev)
 | 
						|
{
 | 
						|
	struct net_local *lp = netdev_priv(dev);
 | 
						|
	int ioaddr = dev->base_addr;
 | 
						|
 | 
						|
	if (el_debug > 2)
 | 
						|
		pr_info("3c501 reset...\n");
 | 
						|
	outb(AX_RESET, AX_CMD);		/* Reset the chip */
 | 
						|
	/* Aux control, irq and loopback enabled */
 | 
						|
	outb(AX_LOOP, AX_CMD);
 | 
						|
	{
 | 
						|
		int i;
 | 
						|
		for (i = 0; i < 6; i++)	/* Set the station address. */
 | 
						|
			outb(dev->dev_addr[i], ioaddr + i);
 | 
						|
	}
 | 
						|
 | 
						|
	outw(0, RX_BUF_CLR);		/* Set rx packet area to 0. */
 | 
						|
	outb(TX_NORM, TX_CMD);		/* tx irq on done, collision */
 | 
						|
	outb(RX_NORM, RX_CMD);		/* Set Rx commands. */
 | 
						|
	inb(RX_STATUS);			/* Clear status. */
 | 
						|
	inb(TX_STATUS);
 | 
						|
	lp->txing = 0;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * el1_close:
 | 
						|
 * @dev: 3c501 card to shut down
 | 
						|
 *
 | 
						|
 * Close a 3c501 card. The IFF_UP flag has been cleared by the user via
 | 
						|
 * the SIOCSIFFLAGS ioctl. We stop any further transmissions being queued,
 | 
						|
 * and then disable the interrupts. Finally we reset the chip. The effects
 | 
						|
 * of the rest will be cleaned up by #el1_open. Always returns 0 indicating
 | 
						|
 * a success.
 | 
						|
 */
 | 
						|
 | 
						|
static int el1_close(struct net_device *dev)
 | 
						|
{
 | 
						|
	int ioaddr = dev->base_addr;
 | 
						|
 | 
						|
	if (el_debug > 2)
 | 
						|
		pr_info("%s: Shutting down Ethernet card at %#x.\n",
 | 
						|
						dev->name, ioaddr);
 | 
						|
 | 
						|
	netif_stop_queue(dev);
 | 
						|
 | 
						|
	/*
 | 
						|
	 *	Free and disable the IRQ.
 | 
						|
	 */
 | 
						|
 | 
						|
	free_irq(dev->irq, dev);
 | 
						|
	outb(AX_RESET, AX_CMD);		/* Reset the chip */
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * set_multicast_list:
 | 
						|
 * @dev: The device to adjust
 | 
						|
 *
 | 
						|
 * Set or clear the multicast filter for this adaptor to use the best-effort
 | 
						|
 * filtering supported. The 3c501 supports only three modes of filtering.
 | 
						|
 * It always receives broadcasts and packets for itself. You can choose to
 | 
						|
 * optionally receive all packets, or all multicast packets on top of this.
 | 
						|
 */
 | 
						|
 | 
						|
static void set_multicast_list(struct net_device *dev)
 | 
						|
{
 | 
						|
	int ioaddr = dev->base_addr;
 | 
						|
 | 
						|
	if (dev->flags & IFF_PROMISC) {
 | 
						|
		outb(RX_PROM, RX_CMD);
 | 
						|
		inb(RX_STATUS);
 | 
						|
	} else if (dev->mc_list || dev->flags & IFF_ALLMULTI) {
 | 
						|
		/* Multicast or all multicast is the same */
 | 
						|
		outb(RX_MULT, RX_CMD);
 | 
						|
		inb(RX_STATUS);		/* Clear status. */
 | 
						|
	} else {
 | 
						|
		outb(RX_NORM, RX_CMD);
 | 
						|
		inb(RX_STATUS);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
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 const 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_3c501;
 | 
						|
 | 
						|
module_param(io, int, 0);
 | 
						|
module_param(irq, int, 0);
 | 
						|
MODULE_PARM_DESC(io, "EtherLink I/O base address");
 | 
						|
MODULE_PARM_DESC(irq, "EtherLink IRQ number");
 | 
						|
 | 
						|
/**
 | 
						|
 * init_module:
 | 
						|
 *
 | 
						|
 * When the driver is loaded as a module this function is called. We fake up
 | 
						|
 * a device structure with the base I/O and interrupt set as if it were being
 | 
						|
 * called from Space.c. This minimises the extra code that would otherwise
 | 
						|
 * be required.
 | 
						|
 *
 | 
						|
 * Returns 0 for success or -EIO if a card is not found. Returning an error
 | 
						|
 * here also causes the module to be unloaded
 | 
						|
 */
 | 
						|
 | 
						|
int __init init_module(void)
 | 
						|
{
 | 
						|
	dev_3c501 = el1_probe(-1);
 | 
						|
	if (IS_ERR(dev_3c501))
 | 
						|
		return PTR_ERR(dev_3c501);
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * cleanup_module:
 | 
						|
 *
 | 
						|
 * The module is being unloaded. We unhook our network device from the system
 | 
						|
 * and then free up the resources we took when the card was found.
 | 
						|
 */
 | 
						|
 | 
						|
void __exit cleanup_module(void)
 | 
						|
{
 | 
						|
	struct net_device *dev = dev_3c501;
 | 
						|
	unregister_netdev(dev);
 | 
						|
	release_region(dev->base_addr, EL1_IO_EXTENT);
 | 
						|
	free_netdev(dev);
 | 
						|
}
 | 
						|
 | 
						|
#endif /* MODULE */
 | 
						|
 | 
						|
MODULE_AUTHOR("Donald Becker, Alan Cox");
 | 
						|
MODULE_DESCRIPTION("Support for the ancient 3Com 3c501 ethernet card");
 | 
						|
MODULE_LICENSE("GPL");
 | 
						|
 |