eexpress.c

powerpc内核mpc8241linux系统下net驱动程序

/* Intel EtherExpress 16 device driver for Linux
 *
 * Written by John Sullivan, 1995
 *  based on original code by Donald Becker, with changes by
 *  Alan Cox and Pauline Middelink.
 *
 * Support for 8-bit mode by Zoltan Szilagyi <[e-mail]>
 *
 * Many modifications, and currently maintained, by
 *  Philip Blundell <[e-mail]>
 * Added the Compaq LTE  Alan Cox <[e-mail]>
 *
 * Note - this driver is experimental still - it has problems on faster
 * machines. Someone needs to sit down and go through it line by line with
 * a databook...
 */

/* The EtherExpress 16 is a fairly simple card, based on a shared-memory
 * design using the i82586 Ethernet coprocessor.  It bears no relationship,
 * as far as I know, to the similarly-named "EtherExpress Pro" range.
 *
 * Historically, Linux support for these cards has been very bad.  However,
 * things seem to be getting better slowly.
 */

/* If your card is confused about what sort of interface it has (eg it
 * persistently reports "10baseT" when none is fitted), running 'SOFTSET /BART'
 * or 'SOFTSET /LISA' from DOS seems to help.
 */

/* Here's the scoop on memory mapping.
 *
 * There are three ways to access EtherExpress card memory: either using the
 * shared-memory mapping, or using PIO through the dataport, or using PIO
 * through the "shadow memory" ports.
 *
 * The shadow memory system works by having the card map some of its memory
 * as follows:
 *
 * (the low five bits of the SMPTR are ignored)
 *
 *  base+0x4000..400f      memory at SMPTR+0..15
 *  base+0x8000..800f      memory at SMPTR+16..31
 *  base+0xc000..c007      dubious stuff (memory at SMPTR+16..23 apparently)
 *  base+0xc008..c00f      memory at 0x0008..0x000f
 *
 * This last set (the one at c008) is particularly handy because the SCB
 * lives at 0x0008.  So that set of ports gives us easy random access to data
 * in the SCB without having to mess around setting up pointers and the like.
 * We always use this method to access the SCB (via the scb_xx() functions).
 *
 * Dataport access works by aiming the appropriate (read or write) pointer
 * at the first address you're interested in, and then reading or writing from
 * the dataport.  The pointers auto-increment after each transfer.  We use
 * this for data transfer.
 *
 * We don't use the shared-memory system because it allegedly doesn't work on
 * all cards, and because it's a bit more prone to go wrong (it's one more
 * thing to configure...).
 */

/* Known bugs:
 *
 * - The card seems to want to give us two interrupts every time something
 *   happens, where just one would be better.
 */

/*
 *
 * Note by Zoltan Szilagyi 10-12-96:
 *
 * I've succeeded in eliminating the "CU wedged" messages, and hence the
 * lockups, which were only occurring with cards running in 8-bit mode ("force
 * 8-bit operation" in Intel's SoftSet utility). This version of the driver
 * sets the 82586 and the ASIC to 8-bit mode at startup; it also stops the
 * CU before submitting a packet for transmission, and then restarts it as soon
 * as the process of handing the packet is complete. This is definitely an
 * unnecessary slowdown if the card is running in 16-bit mode; therefore one
 * should detect 16-bit vs 8-bit mode from the EEPROM settings and act 
 * accordingly. In 8-bit mode with this bugfix I'm getting about 150 K/s for
 * ftp's, which is significantly better than I get in DOS, so the overhead of
 * stopping and restarting the CU with each transmit is not prohibitive in
 * practice.
 */
  
#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/string.h>
#include <linux/in.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/malloc.h>

#ifndef NET_DEBUG
#define NET_DEBUG 4
#endif

#include "eexpress.h"

#define EEXP_IO_EXTENT  16

/*
 * Private data declarations
 */

struct net_local
{
	struct net_device_stats stats;
	unsigned long last_tx;       /* jiffies when last transmit started */
	unsigned long init_time;     /* jiffies when eexp_hw_init586 called */
	unsigned short rx_first;     /* first rx buf, same as RX_BUF_START */
	unsigned short rx_last;      /* last rx buf */
	unsigned short rx_ptr;       /* first rx buf to look at */
	unsigned short tx_head;      /* next free tx buf */
	unsigned short tx_reap;      /* first in-use tx buf */
	unsigned short tx_tail;      /* previous tx buf to tx_head */
	unsigned short tx_link;      /* last known-executing tx buf */
	unsigned short last_tx_restart;   /* set to tx_link when we
					     restart the CU */
	unsigned char started;
	unsigned short rx_buf_start;
	unsigned short rx_buf_end;
	unsigned short num_tx_bufs;
	unsigned short num_rx_bufs;
	unsigned char width;         /* 0 for 16bit, 1 for 8bit */
	unsigned char was_promisc;
	unsigned char old_mc_count;
};

/* This is the code and data that is downloaded to the EtherExpress card's
 * memory at boot time.
 */

static unsigned short start_code[] = {
/* 0x0000 */
	0x0001,                 /* ISCP: busy - cleared after reset */
	0x0008,0x0000,0x0000,   /* offset,address (lo,hi) of SCB */

	0x0000,0x0000,          /* SCB: status, commands */
	0x0000,0x0000,          /* links to first command block,
				   first receive descriptor */
	0x0000,0x0000,          /* CRC error, alignment error counts */
	0x0000,0x0000,          /* out of resources, overrun error counts */

	0x0000,0x0000,          /* pad */
	0x0000,0x0000,

/* 0x20 -- start of 82586 CU program */
#define CONF_LINK 0x20
	0x0000,Cmd_Config,      
	0x0032,                 /* link to next command */
	0x080c,                 /* 12 bytes follow : fifo threshold=8 */
	0x2e40,                 /* don't rx bad frames
				 * SRDY/ARDY => ext. sync. : preamble len=8
	                         * take addresses from data buffers
				 * 6 bytes/address
				 */
	0x6000,                 /* default backoff method & priority
				 * interframe spacing = 0x60 */
	0xf200,                 /* slot time=0x200 
				 * max collision retry = 0xf */
#define CONF_PROMISC  0x2e
	0x0000,                 /* no HDLC : normal CRC : enable broadcast 
				 * disable promiscuous/multicast modes */
	0x003c,                 /* minimum frame length = 60 octets) */

	0x0000,Cmd_SetAddr,
	0x003e,                 /* link to next command */
#define CONF_HWADDR  0x38
	0x0000,0x0000,0x0000,   /* hardware address placed here */

	0x0000,Cmd_MCast,
	0x0076,                 /* link to next command */
#define CONF_NR_MULTICAST 0x44
	0x0000,                 /* number of multicast addresses */
#define CONF_MULTICAST 0x46
	0x0000, 0x0000, 0x0000, /* some addresses */
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,
	0x0000, 0x0000, 0x0000,

#define CONF_DIAG_RESULT  0x76
	0x0000, Cmd_Diag,
	0x007c,                 /* link to next command */

	0x0000,Cmd_TDR|Cmd_INT,
	0x0084,
#define CONF_TDR_RESULT  0x82
	0x0000,

	0x0000,Cmd_END|Cmd_Nop, /* end of configure sequence */
	0x0084                  /* dummy link */
};

/* maps irq number to EtherExpress magic value */
static char irqrmap[] = { 0,0,1,2,3,4,0,0,0,1,5,6,0,0,0,0 };

/*
 * Prototypes for Linux interface
 */

extern int express_probe(struct device *dev);
static int eexp_open(struct device *dev);
static int eexp_close(struct device *dev);
static struct net_device_stats *eexp_stats(struct device *dev);
static int eexp_xmit(struct sk_buff *buf, struct device *dev);

static void eexp_irq(int irq, void *dev_addr, struct pt_regs *regs);
static void eexp_set_multicast(struct device *dev);

/*
 * Prototypes for hardware access functions
 */

static void eexp_hw_rx_pio(struct device *dev);
static void eexp_hw_tx_pio(struct device *dev, unsigned short *buf,
		       unsigned short len);
static int eexp_hw_probe(struct device *dev,unsigned short ioaddr);
static unsigned short eexp_hw_readeeprom(unsigned short ioaddr,
					 unsigned char location);

static unsigned short eexp_hw_lasttxstat(struct device *dev);
static void eexp_hw_txrestart(struct device *dev);

static void eexp_hw_txinit    (struct device *dev);
static void eexp_hw_rxinit    (struct device *dev);

static void eexp_hw_init586   (struct device *dev);
static void eexp_setup_filter (struct device *dev);

static char *eexp_ifmap[]={"AUI", "BNC", "RJ45"};
enum eexp_iftype {AUI=0, BNC=1, TPE=2};

#define STARTED_RU      2
#define STARTED_CU      1

/*
 * Primitive hardware access functions.
 */

static inline unsigned short scb_status(struct device *dev)
{
	return inw(dev->base_addr + 0xc008);
}

static inline unsigned short scb_rdcmd(struct device *dev)
{
	return inw(dev->base_addr + 0xc00a);
}

static inline void scb_command(struct device *dev, unsigned short cmd)
{
	outw(cmd, dev->base_addr + 0xc00a);
}

static inline void scb_wrcbl(struct device *dev, unsigned short val)
{
	outw(val, dev->base_addr + 0xc00c);
}

static inline void scb_wrrfa(struct device *dev, unsigned short val)
{
	outw(val, dev->base_addr + 0xc00e);
}

static inline void set_loopback(struct device *dev)
{
	outb(inb(dev->base_addr + Config) | 2, dev->base_addr + Config);
}

static inline void clear_loopback(struct device *dev)
{
	outb(inb(dev->base_addr + Config) & ~2, dev->base_addr + Config);
}

static inline short int SHADOW(short int addr)
{
	addr &= 0x1f;
	if (addr > 0xf) addr += 0x3ff0;
	return addr + 0x4000;
}

/*
 * Linux interface
 */

/*
 * checks for presence of EtherExpress card
 */

__initfunc(int express_probe(struct device *dev))
{
	unsigned short *port;
	static unsigned short ports[] = { 0x300,0x310,0x270,0x320,0x340,0 };
	unsigned short ioaddr = dev->base_addr;

	if (ioaddr&0xfe00)
		return eexp_hw_probe(dev,ioaddr);
	else if (ioaddr)
		return ENXIO;

	for (port=&ports[0] ; *port ; port++ )
	{
		unsigned short sum = 0;
		int i;
		for ( i=0 ; i<4 ; i++ )
		{
			unsigned short t;
			t = inb(*port + ID_PORT);
			sum |= (t>>4) << ((t & 0x03)<<2);
		}
		if (sum==0xbaba && !eexp_hw_probe(dev,*port))
			return 0;
	}
	return -ENODEV;
}

/*
 * open and initialize the adapter, ready for use
 */

static int eexp_open(struct device *dev)
{
	int irq = dev->irq;
	unsigned short ioaddr = dev->base_addr;
	struct net_local *lp = (struct net_local *)dev->priv;

#if NET_DEBUG > 6
	printk(KERN_DEBUG "%s: eexp_open()\n", dev->name);
#endif

	if (!irq || !irqrmap[irq])
		return -ENXIO;

	if (request_irq(irq,&eexp_irq,0,"EtherExpress",dev))
		return -EAGAIN;

	request_region(ioaddr, EEXP_IO_EXTENT, "EtherExpress");
	request_region(ioaddr+0x4000, 16, "EtherExpress shadow");
	request_region(ioaddr+0x8000, 16, "EtherExpress shadow");
	request_region(ioaddr+0xc000, 16, "EtherExpress shadow");
	dev->tbusy = 0;
	dev->interrupt = 0;
	
	if (lp->width) {
		printk("%s: forcing ASIC to 8-bit mode\n", dev->name);
		outb(inb(dev->base_addr+Config)&~4, dev->base_addr+Config);
	}

	eexp_hw_init586(dev);
	dev->start = 1;
	MOD_INC_USE_COUNT;
#if NET_DEBUG > 6
	printk(KERN_DEBUG "%s: leaving eexp_open()\n", dev->name);
#endif
	return 0;
}

/*
 * close and disable the interface, leaving the 586 in reset.
 */

static int eexp_close(struct device *dev)
{
	unsigned short ioaddr = dev->base_addr;
	struct net_local *lp = dev->priv;

	int irq = dev->irq;

	dev->tbusy = 1;
	dev->start = 0;

	outb(SIRQ_dis|irqrmap[irq],ioaddr+SET_IRQ);
	lp->started = 0;
	scb_command(dev, SCB_CUsuspend|SCB_RUsuspend);
	outb(0,ioaddr+SIGNAL_CA);
	free_irq(irq,dev);
	outb(i586_RST,ioaddr+EEPROM_Ctrl);
	release_region(ioaddr,16);

	MOD_DEC_USE_COUNT;
	return 0;
}

/*
 * Return interface stats
 */

static struct net_device_stats *eexp_stats(struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	return &lp->stats;
}

/*
 * This gets called when a higher level thinks we are broken.  Check that
 * nothing has become jammed in the CU.
 */

static void unstick_cu(struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	unsigned short ioaddr = dev->base_addr;

	if (lp->started)
	{
		if ((jiffies - dev->trans_start)>50)
		{
			if (lp->tx_link==lp->last_tx_restart)
			{
				unsigned short boguscount=200,rsst;
				printk(KERN_WARNING "%s: Retransmit timed out, status %04x, resetting...\n",
				       dev->name, scb_status(dev));
				eexp_hw_txinit(dev);
				lp->last_tx_restart = 0;
				scb_wrcbl(dev, lp->tx_link);
				scb_command(dev, SCB_CUstart);
				outb(0,ioaddr+SIGNAL_CA);
				while (!SCB_complete(rsst=scb_status(dev)))
				{
					if (!--boguscount)
					{
						boguscount=200;
						printk(KERN_WARNING "%s: Reset timed out status %04x, retrying...\n",
						       dev->name,rsst);
						scb_wrcbl(dev, lp->tx_link);
						scb_command(dev, SCB_CUstart);
						outb(0,ioaddr+SIGNAL_CA);
					}
				}
				dev->tbusy = 0;
				mark_bh(NET_BH);
			}
			else
			{
				unsigned short status = scb_status(dev);
				if (SCB_CUdead(status))
				{
					unsigned short txstatus = eexp_hw_lasttxstat(dev);
					printk(KERN_WARNING "%s: Transmit timed out, CU not active status %04x %04x, restarting...\n",
					       dev->name, status, txstatus);
					eexp_hw_txrestart(dev);
				}
				else
				{
					unsigned short txstatus = eexp_hw_lasttxstat(dev);
					if (dev->tbusy && !txstatus)
					{
						printk(KERN_WARNING "%s: CU wedged, status %04x %04x, resetting...\n",
						       dev->name,status,txstatus);
						eexp_hw_init586(dev);
						dev->tbusy = 0;
						mark_bh(NET_BH);
					}
					else
					{
						printk(KERN_WARNING "%s: transmit timed out\n", dev->name);
					}
				}
			}
		}
	}
	else
	{
		if ((jiffies-lp->init_time)>10)
		{
			unsigned short status = scb_status(dev);
			printk(KERN_WARNING "%s: i82586 startup timed out, status %04x, resetting...\n",
			       dev->name, status);
			eexp_hw_init586(dev);
			dev->tbusy = 0;
			mark_bh(NET_BH);
		}
	}
}

/*
 * Called to transmit a packet, or to allow us to right ourselves
 * if the kernel thinks we've died.
 */
static int eexp_xmit(struct sk_buff *buf, struct device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

#if NET_DEBUG > 6
	printk(KERN_DEBUG "%s: eexp_xmit()\n", dev->name);
#endif

	disable_irq(dev->irq);

	/* If dev->tbusy is set, all our tx buffers are full but the kernel
	 * is calling us anyway.  Check that nothing bad is happening.
	 */
	if (dev->tbusy) {
		int status = scb_status(dev);
  		unstick_cu(dev);
		if ((jiffies - lp->last_tx) < HZ)
			return 1;
		printk(KERN_INFO "%s: transmit timed out, %s?", dev->name,
		       (SCB_complete(status)?"lost interrupt":
			"board on fire"));
		lp->stats.tx_errors++;
		dev->tbusy = 0;
		lp->last_tx = jiffies;
		if (!SCB_complete(status)) {
			scb_command(dev, SCB_CUabort);
			outb(0,dev->base_addr+SIGNAL_CA);