ni5010.c

讲述linux的初始化过程

/*	ni5010.c: A network driver for the MiCom-Interlan NI5010 ethercard.
 *
 *	Copyright 1996,1997 Jan-Pascal van Best and Andreas Mohr.
 *
 *	This software may be used and distributed according to the terms
 *	of the GNU Public License, incorporated herein by reference.
 *
 * 	The authors may be reached as:
 *		[e-mail]		[e-mail]
 * 	or by snail mail as
 * 		Jan-Pascal van Best		Andreas Mohr
 *		Klikspaanweg 58-4		Stauferstr. 6
 *		2324 LZ  Leiden			D-71272 Renningen
 *		The Netherlands			Germany
 *
 *	Sources:
 * 	 	Donald Becker's "skeleton.c"
 *  		Crynwr ni5010 packet driver
 *
 *	Changes:
 *		v0.0: First test version
 *		v0.1: First working version
 *		v0.2:
 *		v0.3->v0.90: Now demand setting io and irq when loading as module
 *	970430	v0.91: modified for Linux 2.1.14
 *		v0.92: Implemented Andreas' (better) NI5010 probe
 *	970503	v0.93: Fixed auto-irq failure on warm reboot (JB)
 *	970623	v1.00: First kernel version (AM)
 *	970814	v1.01: Added detection of onboard receive buffer size (AM)
 *	Bugs:
 *		- None known...
 *		- Note that you have to patch ifconfig for the new /proc/net/dev
 *		format. It gives incorrect stats otherwise.
 *
 *	To do:
 *		Fix all bugs :-)
 *		Move some stuff to chipset_init()
 *		Handle xmt errors other than collisions
 *		Complete merge with Andreas' driver
 *		Implement ring buffers (Is this useful? You can't squeeze
 *			too many packet in a 2k buffer!)
 *		Implement DMA (Again, is this useful? Some docs says DMA is
 *			slower than programmed I/O)
 *
 *	Compile with:
 *		gcc -O2 -fomit-frame-pointer -m486 -D__KERNEL__ \
 *			-DMODULE -c ni5010.c 
 *
 *	Insert with e.g.:
 *		insmod ni5010.o io=0x300 irq=5 	
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/malloc.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <asm/dma.h>

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

#include "ni5010.h"

static const char *boardname = "NI5010";
static char *version =
	"ni5010.c: v1.00 06/23/97 Jan-Pascal van Best and Andreas Mohr\n";
	
/* bufsize_rcv == 0 means autoprobing */
static unsigned int bufsize_rcv = 0;

#define jumpered_interrupts	/* IRQ line jumpered on board */
#undef jumpered_dma		/* No DMA used */
#undef FULL_IODETECT		/* Only detect in portlist */

#ifndef FULL_IODETECT
/* A zero-terminated list of I/O addresses to be probed. */
static unsigned int ni5010_portlist[] __initdata =
	{ 0x300, 0x320, 0x340, 0x360, 0x380, 0x3a0, 0 };
#endif

/* Use 0 for production, 1 for verification, >2 for debug */
#ifndef NI5010_DEBUG
#define NI5010_DEBUG 0
#endif

/* Information that needs to be kept for each board. */
struct ni5010_local {
	struct net_device_stats stats;
	int o_pkt_size;
	int i_pkt_size;
};

/* Index to functions, as function prototypes. */

extern int 	ni5010_probe(struct net_device *dev);
static int	ni5010_probe1(struct net_device *dev, int ioaddr);
static int	ni5010_open(struct net_device *dev);
static int	ni5010_send_packet(struct sk_buff *skb, struct net_device *dev);
static void	ni5010_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static void	ni5010_rx(struct net_device *dev);
static void	ni5010_timeout(struct net_device *dev);
static int	ni5010_close(struct net_device *dev);
static struct net_device_stats *ni5010_get_stats(struct net_device *dev);
static void 	ni5010_set_multicast_list(struct net_device *dev);
static void	reset_receiver(struct net_device *dev);

static int	process_xmt_interrupt(struct net_device *dev);
#define tx_done(dev) 1
static void	hardware_send_packet(struct net_device *dev, char *buf, int length);
static void 	chipset_init(struct net_device *dev, int startp);
static void	dump_packet(void *buf, int len);
static void 	show_registers(struct net_device *dev);


int __init ni5010_probe(struct net_device *dev)
{
	int *port;
	int base_addr = dev->base_addr;

        PRINTK2((KERN_DEBUG "%s: Entering ni5010_probe\n", dev->name));

	SET_MODULE_OWNER(dev);

	if (base_addr > 0x1ff)		/* Check a single specified location. */
		return ni5010_probe1(dev, base_addr);
	else if (base_addr != 0)	/* Don't probe at all. */
		return -ENXIO;

#ifdef FULL_IODETECT
		for (int ioaddr=0x200; ioaddr<0x400; ioaddr+=0x20) {
			if (check_region(ioaddr, NI5010_IO_EXTENT))
				continue;
			if (ni5010_probe1(dev, ioaddr) == 0)
				return 0;
		}
#else
		for (port = ni5010_portlist; *port; port++) {
			int ioaddr = *port;
			if (check_region(ioaddr, NI5010_IO_EXTENT))
				continue;
			if (ni5010_probe1(dev, ioaddr) == 0)
				return 0;
		}
#endif	/* FULL_IODETECT */
	return -ENODEV;
}

static inline int rd_port(int ioaddr)
{
	inb(IE_RBUF);
	return inb(IE_SAPROM);
}

static void __init trigger_irq(int ioaddr)
{
		outb(0x00, EDLC_RESET);	/* Clear EDLC hold RESET state */
		outb(0x00, IE_RESET);	/* Board reset */
		outb(0x00, EDLC_XMASK);	/* Disable all Xmt interrupts */
		outb(0x00, EDLC_RMASK); /* Disable all Rcv interrupt */
		outb(0xff, EDLC_XCLR);	/* Clear all pending Xmt interrupts */
		outb(0xff, EDLC_RCLR);	/* Clear all pending Rcv interrupts */
		/*
		 * Transmit packet mode: Ignore parity, Power xcvr,
		 * 	Enable loopback
		 */
		outb(XMD_IG_PAR | XMD_T_MODE | XMD_LBC, EDLC_XMODE);
		outb(RMD_BROADCAST, EDLC_RMODE); /* Receive normal&broadcast */
		outb(XM_ALL, EDLC_XMASK);	/* Enable all Xmt interrupts */
		udelay(50);			/* FIXME: Necessary? */
		outb(MM_EN_XMT|MM_MUX, IE_MMODE); /* Start transmission */
}

/*
 *      This is the real probe routine.  Linux has a history of friendly device
 *      probes on the ISA bus.  A good device probes avoids doing writes, and
 *      verifies that the correct device exists and functions.
 */

static int __init ni5010_probe1(struct net_device *dev, int ioaddr)
{
	static unsigned version_printed = 0;
	int i;
	unsigned int data = 0;
	int boguscount = 40;

	/*
	 * This is no "official" probe method, I've rather tested which
	 * probe works best with my seven NI5010 cards
	 * (they have very different serial numbers)
	 * Suggestions or failure reports are very, very welcome !
	 * But I think it is a relatively good probe method
	 * since it doesn't use any "outb"
	 * It should be nearly 100% reliable !
	 * well-known WARNING: this probe method (like many others)
	 * will hang the system if a NE2000 card region is probed !
	 *
	 *   - Andreas
	 */
	
 	PRINTK2((KERN_DEBUG "%s: entering ni5010_probe1(%#3x)\n", 
 		dev->name, ioaddr));

	if (inb(ioaddr+0) == 0xff) return -ENODEV;

	while ( (rd_port(ioaddr) & rd_port(ioaddr) & rd_port(ioaddr) &
		 rd_port(ioaddr) & rd_port(ioaddr) & rd_port(ioaddr)) != 0xff)
	{
		if (boguscount-- == 0) return -ENODEV;
	}

	PRINTK2((KERN_DEBUG "%s: I/O #1 passed!\n", dev->name));

	for (i=0; i<32; i++)
		if ( (data = rd_port(ioaddr)) != 0xff) break;
	if (data==0xff) return -ENODEV;

	PRINTK2((KERN_DEBUG "%s: I/O #2 passed!\n", dev->name));

	if (		(data == SA_ADDR0) &&
	     (rd_port(ioaddr) == SA_ADDR1) &&
	     (rd_port(ioaddr) == SA_ADDR2) ) {
		for (i=0; i<4; i++) rd_port(ioaddr);
		if ( (rd_port(ioaddr) != NI5010_MAGICVAL1) ||
		     (rd_port(ioaddr) != NI5010_MAGICVAL2) ) {
		     	return -ENODEV;
		}
	} else return -ENODEV;
	
	PRINTK2((KERN_DEBUG "%s: I/O #3 passed!\n", dev->name));

	if (NI5010_DEBUG && version_printed++ == 0)
		printk(KERN_INFO "%s", version);

	printk("NI5010 ethercard probe at 0x%x: ", ioaddr);

	dev->base_addr = ioaddr;

	for (i=0; i<6; i++) {
		outw(i, IE_GP);
		printk("%2.2x ", dev->dev_addr[i] = inb(IE_SAPROM));
	}

	PRINTK2((KERN_DEBUG "%s: I/O #4 passed!\n", dev->name));

#ifdef jumpered_interrupts
	if (dev->irq == 0xff)
		;
	else if (dev->irq < 2) {
		PRINTK2((KERN_DEBUG "%s: I/O #5 passed!\n", dev->name));

		autoirq_setup(0);
		trigger_irq(ioaddr);
		dev->irq = autoirq_report(2);

		PRINTK2((KERN_DEBUG "%s: I/O #6 passed!\n", dev->name));

		if (dev->irq == 0) {
			printk(KERN_WARNING "%s: no IRQ found!\n", dev->name);
			return -EAGAIN;
		}
		PRINTK2((KERN_DEBUG "%s: I/O #7 passed!\n", dev->name));
	} else if (dev->irq == 2) {
		dev->irq = 9;
	}
#endif	/* jumpered_irq */
	PRINTK2((KERN_DEBUG "%s: I/O #9 passed!\n", dev->name));

	/* DMA is not supported (yet?), so no use detecting it */

	if (dev->priv == NULL) {
		dev->priv = kmalloc(sizeof(struct ni5010_local), GFP_KERNEL|GFP_DMA);
		if (dev->priv == NULL) {
			printk(KERN_WARNING "%s: Failed to allocate private memory\n", dev->name);
			return -ENOMEM;
		}
	}

	PRINTK2((KERN_DEBUG "%s: I/O #10 passed!\n", dev->name));

/* get the size of the onboard receive buffer
 * higher addresses than bufsize are wrapped into real buffer
 * i.e. data for offs. 0x801 is written to 0x1 with a 2K onboard buffer
 */
	if (!bufsize_rcv) {
        	outb(1, IE_MMODE);      /* Put Rcv buffer on system bus */
        	outw(0, IE_GP);		/* Point GP at start of packet */
        	outb(0, IE_RBUF);	/* set buffer byte 0 to 0 */
        	for (i = 1; i < 0xff; i++) {
                	outw(i << 8, IE_GP); /* Point GP at packet size to be tested */
                	outb(i, IE_RBUF);
                	outw(0x0, IE_GP); /* Point GP at start of packet */
                	data = inb(IE_RBUF);
                	if (data == i) break;
        	}
		bufsize_rcv = i << 8;
        	outw(0, IE_GP);		/* Point GP at start of packet */
        	outb(0, IE_RBUF);	/* set buffer byte 0 to 0 again */
	}
        printk("// bufsize rcv/xmt=%d/%d\n", bufsize_rcv, NI5010_BUFSIZE);
	memset(dev->priv, 0, sizeof(struct ni5010_local));

	/* Grab the region so we can find another board if autoIRQ fails. */
	request_region(ioaddr, NI5010_IO_EXTENT, boardname);
	
	dev->open		= ni5010_open;
	dev->stop		= ni5010_close;
	dev->hard_start_xmit	= ni5010_send_packet;
	dev->get_stats		= ni5010_get_stats;
	dev->set_multicast_list = ni5010_set_multicast_list;
	dev->tx_timeout		= ni5010_timeout;
	dev->watchdog_timeo	= HZ/20;

	/* Fill in the fields of the device structure with ethernet values. */
	ether_setup(dev);
	
	dev->flags &= ~IFF_MULTICAST;	/* Multicast doesn't work */

	/* Shut up the ni5010 */
	outb(0, EDLC_RMASK);	/* Mask all receive interrupts */
	outb(0, EDLC_XMASK);	/* Mask all xmit interrupts */
	outb(0xff, EDLC_RCLR);	/* Kill all pending rcv interrupts */
	outb(0xff, EDLC_XCLR); 	/* Kill all pending xmt interrupts */

	printk(KERN_INFO "%s: NI5010 found at 0x%x, using IRQ %d", dev->name, ioaddr, dev->irq);
	if (dev->dma) printk(" & DMA %d", dev->dma);
	printk(".\n");

	printk(KERN_INFO "Join the NI5010 driver development team!\n");
	printk(KERN_INFO "Mail to [e-mail] or [e-mail]\n");
	return 0;
}

/* 
 * Open/initialize the board.  This is called (in the current kernel)
 * sometime after booting when the 'ifconfig' program is run.
 *
 * This routine should set everything up anew at each open, even
 * registers that "should" only need to be set once at boot, so that
 * there is non-reboot way to recover if something goes wrong.
 */
   
static int ni5010_open(struct net_device *dev)
{
	int ioaddr = dev->base_addr;
	int i;

	PRINTK2((KERN_DEBUG "%s: entering ni5010_open()\n", dev->name)); 
	
	if (request_irq(dev->irq, &ni5010_interrupt, 0, boardname, dev)) {
		printk(KERN_WARNING "%s: Cannot get irq %#2x\n", dev->name, dev->irq);
		return -EAGAIN;
	}
	PRINTK3((KERN_DEBUG "%s: passed open() #1\n", dev->name));
        /*
         * Always allocate the DMA channel after the IRQ,
         * and clean up on failure.
         */
#ifdef jumpered_dma
        if (request_dma(dev->dma, cardname)) {
		printk(KERN_WARNING "%s: Cannot get dma %#2x\n", dev->name, dev->dma);
                free_irq(dev->irq, NULL);
                return -EAGAIN;
        }
#endif	/* jumpered_dma */

	PRINTK3((KERN_DEBUG "%s: passed open() #2\n", dev->name));
	/* Reset the hardware here.  Don't forget to set the station address. */

	outb(RS_RESET, EDLC_RESET);	/* Hold up EDLC_RESET while configing board */
	outb(0, IE_RESET);		/* Hardware reset of ni5010 board */
	outb(XMD_LBC, EDLC_XMODE);	/* Only loopback xmits */

	PRINTK3((KERN_DEBUG "%s: passed open() #3\n", dev->name));
	/* Set the station address */
	for(i = 0;i < 6; i++) {
		outb(dev->dev_addr[i], EDLC_ADDR + i);
	}
	
	PRINTK3((KERN_DEBUG "%s: Initialising ni5010\n", dev->name)); 
	outb(0, EDLC_XMASK);	/* No xmit interrupts for now */
	outb(XMD_IG_PAR | XMD_T_MODE | XMD_LBC, EDLC_XMODE); 
				/* Normal packet xmit mode */
	outb(0xff, EDLC_XCLR);	/* Clear all pending xmit interrupts */
	outb(RMD_BROADCAST, EDLC_RMODE);
				/* Receive broadcast and normal packets */
	reset_receiver(dev);	/* Ready ni5010 for receiving packets */
	
	outb(0, EDLC_RESET);	/* Un-reset the ni5010 */