/* cs89x0.c: A Crystal Semiconductor (Now Cirrus Logic) CS89[02]0
 *  driver for linux.
 */

/*
	Written 1996 by Russell Nelson, with reference to skeleton.c
	written 1993-1994 by Donald Becker.

	This software may be used and distributed according to the terms
	of the GNU General Public License, incorporated herein by reference.

        The author may be reached at nelson@crynwr.com, Crynwr
        Software, 521 Pleasant Valley Rd., Potsdam, NY 13676

  Changelog:

  Mike Cruse        : mcruse@cti-ltd.com
                    : Changes for Linux 2.0 compatibility. 
                    : Added dev_id parameter in net_interrupt(),
                    : request_irq() and free_irq(). Just NULL for now.

  Mike Cruse        : Added MOD_INC_USE_COUNT and MOD_DEC_USE_COUNT macros
                    : in net_open() and net_close() so kerneld would know
                    : that the module is in use and wouldn't eject the 
                    : driver prematurely.

  Mike Cruse        : Rewrote init_module() and cleanup_module using 8390.c
                    : as an example. Disabled autoprobing in init_module(),
                    : not a good thing to do to other devices while Linux
                    : is running from all accounts.

  Russ Nelson       : Jul 13 1998.  Added RxOnly DMA support.

  Melody Lee        : Aug 10 1999.  Changes for Linux 2.2.5 compatibility. 
                    : email: ethernet@crystal.cirrus.com

  Alan Cox          : Removed 1.2 support, added 2.1 extra counters.

  Andrew Morton     : andrewm@uow.edu.au
                    : Kernel 2.3.48
                    : Handle kmalloc() failures
                    : Other resource allocation fixes
                    : Add SMP locks
                    : Integrate Russ Nelson's ALLOW_DMA functionality back in.
                    : If ALLOW_DMA is true, make DMA runtime selectable
                    : Folded in changes from Cirrus (Melody Lee
                    : <klee@crystal.cirrus.com>)
                    : Don't call netif_wake_queue() in net_send_packet()
                    : Fixed an out-of-mem bug in dma_rx()
                    : Updated Documentation/cs89x0.txt

  Andrew Morton     : andrewm@uow.edu.au / Kernel 2.3.99-pre1
                    : Use skb_reserve to longword align IP header (two places)
                    : Remove a delay loop from dma_rx()
                    : Replace '100' with HZ
                    : Clean up a couple of skb API abuses
                    : Added 'cs89x0_dma=N' kernel boot option
                    : Correctly initialise lp->lock in non-module compile

  Andrew Morton     : andrewm@uow.edu.au / Kernel 2.3.99-pre4-1
                    : MOD_INC/DEC race fix (see
                    : http://www.uwsg.indiana.edu/hypermail/linux/kernel/0003.3/1532.html)

  Andrew Morton     : andrewm@uow.edu.au / Kernel 2.4.0-test7-pre2
                    : Enhanced EEPROM support to cover more devices,
                    :   abstracted IRQ mapping to support CONFIG_ARCH_CLPS7500 arch
                    :   (Jason Gunthorpe <jgg@ualberta.ca>)

  Andrew Morton     : Kernel 2.4.0-test11-pre4
                    : Use dev->name in request_*() (Andrey Panin)
                    : Fix an error-path memleak in init_module()
                    : Preserve return value from request_irq()
                    : Fix type of `media' module parm (Keith Owens)
                    : Use SET_MODULE_OWNER()
                    : Tidied up strange request_irq() abuse in net_open().

  Andrew Morton     : Kernel 2.4.3-pre1
                    : Request correct number of pages for DMA (Hugh Dickens)
                    : Select PP_ChipID _after_ unregister_netdev in cleanup_module()
                    :  because unregister_netdev() calls get_stats.
                    : Make `version[]' __initdata
                    : Uninlined the read/write reg/word functions.

*/

/* Always include 'config.h' first in case the user wants to turn on
   or override something. */
#include <linux/config.h>
#include <linux/module.h>
#include <linux/version.h>

/*
 * Set this to zero to disable DMA code
 *
 * Note that even if DMA is turned off we still support the 'dma' and  'use_dma'
 * module options so we don't break any startup scripts.
 */
#define ALLOW_DMA	1

/*
 * Set this to zero to remove all the debug statements via
 * dead code elimination
 */
#define DEBUGGING	1

/*
  Sources:

	Crynwr packet driver epktisa.

	Crystal Semiconductor data sheets.

*/

#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/in.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/init.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/io.h>
#if ALLOW_DMA
#include <asm/dma.h>
#endif
#include <linux/errno.h>
#include <linux/spinlock.h>

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

#include "cs89x0.h"

static char version[] __initdata =
"cs89x0.c: v2.4.3-pre1 Russell Nelson <nelson@crynwr.com>, Andrew Morton <andrewm@uow.edu.au>\n";

/* First, a few definitions that the brave might change.
   A zero-terminated list of I/O addresses to be probed. Some special flags..
      Addr & 1 = Read back the address port, look for signature and reset
                 the page window before probing 
      Addr & 3 = Reset the page window and probe 
   The CLPS eval board has the Cirrus chip at 0x80090300, in ARM IO space,
   but it is possible that a Cirrus board could be plugged into the ISA
   slots. */
/* The cs8900 has 4 IRQ pins, software selectable. cs8900_irq_map maps 
   them to system IRQ numbers. This mapping is card specific and is set to
   the configuration of the Cirrus Eval board for this chip. */
#ifdef CONFIG_ARCH_CLPS7500
static unsigned int netcard_portlist[] __initdata =
   { 0x80090303, 0x300, 0x320, 0x340, 0x360, 0x200, 0x220, 0x240, 0x260, 0x280, 0x2a0, 0x2c0, 0x2e0, 0};
static unsigned int cs8900_irq_map[] = {12,0,0,0};
#else
static unsigned int netcard_portlist[] __initdata =
   { 0x300, 0x320, 0x340, 0x360, 0x200, 0x220, 0x240, 0x260, 0x280, 0x2a0, 0x2c0, 0x2e0, 0};
static unsigned int cs8900_irq_map[] = {10,11,12,5};
#endif

#if DEBUGGING
static unsigned int net_debug = DEBUGGING;
#else
#define net_debug 0	/* gcc will remove all the debug code for us */
#endif

/* The number of low I/O ports used by the ethercard. */
#define NETCARD_IO_EXTENT	16

/* we allow the user to override various values normally set in the EEPROM */
#define FORCE_RJ45	0x0001    /* pick one of these three */
#define FORCE_AUI	0x0002
#define FORCE_BNC	0x0004

#define FORCE_AUTO	0x0010    /* pick one of these three */
#define FORCE_HALF	0x0020
#define FORCE_FULL	0x0030

/* Information that need to be kept for each board. */
struct net_local {
	struct net_device_stats stats;
	int chip_type;		/* one of: CS8900, CS8920, CS8920M */
	char chip_revision;	/* revision letter of the chip ('A'...) */
	int send_cmd;		/* the proper send command: TX_NOW, TX_AFTER_381, or TX_AFTER_ALL */
	int auto_neg_cnf;	/* auto-negotiation word from EEPROM */
	int adapter_cnf;	/* adapter configuration from EEPROM */
	int isa_config;		/* ISA configuration from EEPROM */
	int irq_map;		/* IRQ map from EEPROM */
	int rx_mode;		/* what mode are we in? 0, RX_MULTCAST_ACCEPT, or RX_ALL_ACCEPT */
	int curr_rx_cfg;	/* a copy of PP_RxCFG */
	int linectl;		/* either 0 or LOW_RX_SQUELCH, depending on configuration. */
	int send_underrun;	/* keep track of how many underruns in a row we get */
	int force;		/* force various values; see FORCE* above. */
	spinlock_t lock;
#if ALLOW_DMA
	int use_dma;		/* Flag: we're using dma */
	int dma;		/* DMA channel */
	int dmasize;		/* 16 or 64 */
	unsigned char *dma_buff;	/* points to the beginning of the buffer */
	unsigned char *end_dma_buff;	/* points to the end of the buffer */
	unsigned char *rx_dma_ptr;	/* points to the next packet  */
#endif
};

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

extern int cs89x0_probe(struct net_device *dev);

static int cs89x0_probe1(struct net_device *dev, int ioaddr);
static int net_open(struct net_device *dev);
static int net_send_packet(struct sk_buff *skb, struct net_device *dev);
static void net_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static void set_multicast_list(struct net_device *dev);
static void net_timeout(struct net_device *dev);
static void net_rx(struct net_device *dev);
static int net_close(struct net_device *dev);
static struct net_device_stats *net_get_stats(struct net_device *dev);
static void reset_chip(struct net_device *dev);
static int get_eeprom_data(struct net_device *dev, int off, int len, int *buffer);
static int get_eeprom_cksum(int off, int len, int *buffer);
static int set_mac_address(struct net_device *dev, void *addr);
static void count_rx_errors(int status, struct net_local *lp);
#if ALLOW_DMA
static void get_dma_channel(struct net_device *dev);
static void release_dma_buff(struct net_local *lp);
#endif

/* Example routines you must write ;->. */
#define tx_done(dev) 1

/*
 * Permit 'cs89x0_dma=N' in the kernel boot environment
 */
#if !defined(MODULE) && (ALLOW_DMA != 0)
static int g_cs89x0_dma;

static int __init dma_fn(char *str)
{
	g_cs89x0_dma = simple_strtol(str,NULL,0);
	return 1;
}

__setup("cs89x0_dma=", dma_fn);
#endif	/* !defined(MODULE) && (ALLOW_DMA != 0) */


/* Check for a network adaptor of this type, and return '0' iff one exists.
   If dev->base_addr == 0, probe all likely locations.
   If dev->base_addr == 1, always return failure.
   If dev->base_addr == 2, allocate space for the device and return success
   (detachable devices only).
   Return 0 on success.
   */

int __init cs89x0_probe(struct net_device *dev)
{
	int i;
	int base_addr = dev ? dev->base_addr : 0;

	SET_MODULE_OWNER(dev);

	if (net_debug)
		printk("cs89x0:cs89x0_probe(0x%x)\n", base_addr);

	if (base_addr > 0x1ff)		/* Check a single specified location. */
		return cs89x0_probe1(dev, base_addr);
	else if (base_addr != 0)	/* Don't probe at all. */
		return -ENXIO;

	for (i = 0; netcard_portlist[i]; i++) {
		if (cs89x0_probe1(dev, netcard_portlist[i]) == 0)
			return 0;
	}
	printk(KERN_WARNING "cs89x0: no cs8900 or cs8920 detected.  Be sure to disable PnP with SETUP\n");
	return -ENODEV;
}

static int
readreg(struct net_device *dev, int portno)
{
	outw(portno, dev->base_addr + ADD_PORT);
	return inw(dev->base_addr + DATA_PORT);
}

static void
writereg(struct net_device *dev, int portno, int value)
{
	outw(portno, dev->base_addr + ADD_PORT);
	outw(value, dev->base_addr + DATA_PORT);
}

static int
readword(struct net_device *dev, int portno)
{
	return inw(dev->base_addr + portno);
}

static void
writeword(struct net_device *dev, int portno, int value)
{
	outw(value, dev->base_addr + portno);
}

static int __init
wait_eeprom_ready(struct net_device *dev)
{
	int timeout = jiffies;
	/* check to see if the EEPROM is ready, a timeout is used -
	   just in case EEPROM is ready when SI_BUSY in the
	   PP_SelfST is clear */
	while(readreg(dev, PP_SelfST) & SI_BUSY)
		if (jiffies - timeout >= 40)
			return -1;
	return 0;
}

static int __init
get_eeprom_data(struct net_device *dev, int off, int len, int *buffer)
{
	int i;

	if (net_debug > 3) printk("EEPROM data from %x for %x:\n",off,len);
	for (i = 0; i < len; i++) {
		if (wait_eeprom_ready(dev) < 0) return -1;
		/* Now send the EEPROM read command and EEPROM location to read */
		writereg(dev, PP_EECMD, (off + i) | EEPROM_READ_CMD);
		if (wait_eeprom_ready(dev) < 0) return -1;
		buffer[i] = readreg(dev, PP_EEData);
		if (net_debug > 3) printk("%04x ", buffer[i]);
	}
	if (net_debug > 3) printk("\n");
        return 0;
}

static int  __init
get_eeprom_cksum(int off, int len, int *buffer)
{
	int i, cksum;

	cksum = 0;
	for (i = 0; i < len; i++)
		cksum += buffer[i];
	cksum &= 0xffff;
	if (cksum == 0)
		return 0;
	return -1;
}

/* 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.
   Return 0 on success.
 */

static int __init
cs89x0_probe1(struct net_device *dev, int ioaddr)
{
	struct net_local *lp;
	static unsigned version_printed;
	int i;
	unsigned rev_type = 0;
	int eeprom_buff[CHKSUM_LEN];
	int retval;

	/* Initialize the device structure. */
	if (dev->priv == NULL) {
		dev->priv = kmalloc(sizeof(struct net_local), GFP_KERNEL);
		if (dev->priv == 0) {
			retval = -ENOMEM;
			goto out;
		}
		lp = (struct net_local *)dev->priv;
		memset(lp, 0, sizeof(*lp));
		spin_lock_init(&lp->lock);
#if !defined(MODULE) && (ALLOW_DMA != 0)
		if (g_cs89x0_dma) {
			lp->use_dma = 1;
			lp->dma = g_cs89x0_dma;
			lp->dmasize = 16;	/* Could make this an option... */
		}
#endif
        }
	lp = (struct net_local *)dev->priv;

	/* Grab the region so we can find another board if autoIRQ fails. */
	if (!request_region(ioaddr & ~3, NETCARD_IO_EXTENT, dev->name)) {
		printk(KERN_ERR "%s: request_region(0x%x, 0x%x) failed\n",
				dev->name, ioaddr, NETCARD_IO_EXTENT);
		retval = -EBUSY;
		goto out1;
	}

	/* if they give us an odd I/O address, then do ONE write to
           the address port, to get it back to address zero, where we
           expect to find the EISA signature word. An IO with a base of 0x3
	   will skip the test for the ADD_PORT. */
	if (ioaddr & 1) {
		if (net_debug > 1)
			printk(KERN_INFO "%s: odd ioaddr 0x%x\n", dev->name, ioaddr);
	        if ((ioaddr & 2) != 2)
	        	if ((inw((ioaddr & ~3)+ ADD_PORT) & ADD_MASK) != ADD_SIG) {
				printk(KERN_ERR "%s: bad signature 0x%x\n",
					dev->name, inw((ioaddr & ~3)+ ADD_PORT));
		        	retval = -ENODEV;
				goto out2;
			}
		ioaddr &= ~3;
		outw(PP_ChipID, ioaddr + ADD_PORT);
	}
printk("PP_addr=0x%x\n", inw(ioaddr + ADD_PORT));

        if (inw(ioaddr + DATA_PORT) != CHIP_EISA_ID_SIG) {
		printk(KERN_ERR "%s: incorrect signature 0x%x\n",
			dev->name, inw(ioaddr + DATA_PORT));
  		retval = -ENODEV;
  		goto out2;
	}

	/* Fill in the 'dev' fields. */
	dev->base_addr = ioaddr;

	/* get the chip type */
	rev_type = readreg(dev, PRODUCT_ID_ADD);
	lp->chip_type = rev_type &~ REVISON_BITS;
	lp->chip_revision = ((rev_type & REVISON_BITS) >> 8) + 'A';

	/* Check the chip type and revision in order to set the correct send command
	CS8920 revision C and CS8900 revision F can use the faster send. */
	lp->send_cmd = TX_AFTER_381;
	if (lp->chip_type == CS8900 && lp->chip_revision >= 'F')
		lp->send_cmd = TX_NOW;
	if (lp->chip_type != CS8900 && lp->chip_revision >= 'C')
		lp->send_cmd = TX_NOW;

	if (net_debug  &&  version_printed++ == 0)
		printk(version);

	printk(KERN_INFO "%s: cs89%c0%s rev %c found at %#3lx ",
	       dev->name,
	       lp->chip_type==CS8900?'0':'2',
	       lp->chip_type==CS8920M?"M":"",
	       lp->chip_revision,
	       dev->base_addr);

	reset_chip(dev);
   
        /* Here we read the current configuration of the chip. If there
	   is no Extended EEPROM then the idea is to not disturb the chip
	   configuration, it should have been correctly setup by automatic
	   EEPROM read on reset. So, if the chip says it read the EEPROM
	   the driver will always do *something* instead of complain that
	   adapter_cnf is 0. */
        if ((readreg(dev, PP_SelfST) & (EEPROM_OK | EEPROM_PRESENT)) == 
	      (EEPROM_OK|EEPROM_PRESENT)) {
	        /* Load the MAC. */
		for (i=0; i < ETH_ALEN/2; i++) {
	                unsigned int Addr;
			Addr = readreg(dev, PP_IA+i*2);
		        dev->dev_addr[i*2] = Addr & 0xFF;
		        dev->dev_addr[i*2+1] = Addr >> 8;
		}
   
	   	/* Load the Adapter Configuration. 
		   Note:  Barring any more specific information from some 
		   other source (ie EEPROM+Schematics), we would not know 
		   how to operate a 10Base2 interface on the AUI port. 
		   However, since we  do read the status of HCB1 and use 
		   settings that always result in calls to control_dc_dc(dev,0) 
		   a BNC interface should work if the enable pin 
		   (dc/dc converter) is on HCB1. It will be called AUI 
		   however. */
	   
		lp->adapter_cnf = 0;
		i = readreg(dev, PP_LineCTL);
		/* Preserve the setting of the HCB1 pin. */
		if ((i & (HCB1 | HCB1_ENBL)) ==  (HCB1 | HCB1_ENBL))
			lp->adapter_cnf |= A_CNF_DC_DC_POLARITY;
		/* Save the sqelch bit */
		if ((i & LOW_RX_SQUELCH) == LOW_RX_SQUELCH)
			lp->adapter_cnf |= A_CNF_EXTND_10B_2 | A_CNF_LOW_RX_SQUELCH;
		/* Check if the card is in 10Base-t only mode */
		if ((i & (AUI_ONLY | AUTO_AUI_10BASET)) == 0)
			lp->adapter_cnf |=  A_CNF_10B_T | A_CNF_MEDIA_10B_T;
		/* Check if the card is in AUI only mode */
		if ((i & (AUI_ONLY | AUTO_AUI_10BASET)) == AUI_ONLY)
			lp->adapter_cnf |=  A_CNF_AUI | A_CNF_MEDIA_AUI;
		/* Check if the card is in Auto mode. */
		if ((i & (AUI_ONLY | AUTO_AUI_10BASET)) == AUTO_AUI_10BASET)
			lp->adapter_cnf |=  A_CNF_AUI | A_CNF_10B_T | 
			A_CNF_MEDIA_AUI | A_CNF_MEDIA_10B_T | A_CNF_MEDIA_AUTO;
		
		if (net_debug > 1)
			printk(KERN_INFO "%s: PP_LineCTL=0x%x, adapter_cnf=0x%x\n",
					dev->name, i, lp->adapter_cnf);

		/* IRQ. Other chips already probe, see below. */
		if (lp->chip_type == CS8900) 
			lp->isa_config = readreg(dev, PP_CS8900_ISAINT) & INT_NO_MASK;
	   
		printk( "[Cirrus EEPROM] ");
	}

        printk("\n");
   
	/* First check to see if an EEPROM is attached. */
	if ((readreg(dev, PP_SelfST) & EEPROM_PRESENT) == 0)
		printk(KERN_WARNING "cs89x0: No EEPROM, relying on command line....\n");
	else if (get_eeprom_data(dev, START_EEPROM_DATA,CHKSUM_LEN,eeprom_buff) < 0) {
		printk(KERN_WARNING "\ncs89x0: EEPROM read failed, relying on command line.\n");
        } else if (get_eeprom_cksum(START_EEPROM_DATA,CHKSUM_LEN,eeprom_buff) < 0) {
		/* Check if the chip was able to read its own configuration starting
		   at 0 in the EEPROM*/
		if ((readreg(dev, PP_SelfST) & (EEPROM_OK | EEPROM_PRESENT)) !=
		    (EEPROM_OK|EEPROM_PRESENT)) 
                	printk(KERN_WARNING "cs89x0: Extended EEPROM checksum bad and no Cirrus EEPROM, relying on command line\n");
		   
        } else {
		/* This reads an extended EEPROM that is not documented
		   in the CS8900 datasheet. */
		
                /* get transmission control word  but keep the autonegotiation bits */
                if (!lp->auto_neg_cnf) lp->auto_neg_cnf = eeprom_buff[AUTO_NEG_CNF_OFFSET/2];
                /* Store adapter configuration */
                if (!lp->adapter_cnf) lp->adapter_cnf = eeprom_buff[ADAPTER_CNF_OFFSET/2];
                /* Store ISA configuration */
                lp->isa_config = eeprom_buff[ISA_CNF_OFFSET/2];
                dev->mem_start = eeprom_buff[PACKET_PAGE_OFFSET/2] << 8;

                /* eeprom_buff has 32-bit ints, so we can't just memcpy it */
                /* store the initial memory base address */
                for (i = 0; i < ETH_ALEN/2; i++) {
                        dev->dev_addr[i*2] = eeprom_buff[i];
                        dev->dev_addr[i*2+1] = eeprom_buff[i] >> 8;
                }
		if (net_debug > 1)
			printk(KERN_DEBUG "%s: new adapter_cnf: 0%x\n",
				dev->name, lp->adapter_cnf);
        }

        /* allow them to force multiple transceivers.  If they force multiple, autosense */
        {
		int count = 0;
		if (lp->force & FORCE_RJ45)	{lp->adapter_cnf |= A_CNF_10B_T; count++; }
		if (lp->force & FORCE_AUI) 	{lp->adapter_cnf |= A_CNF_AUI; count++; }
		if (lp->force & FORCE_BNC)	{lp->adapter_cnf |= A_CNF_10B_2; count++; }
		if (count > 1)			{lp->adapter_cnf |= A_CNF_MEDIA_AUTO; }
		else if (lp->force & FORCE_RJ45){lp->adapter_cnf |= A_CNF_MEDIA_10B_T; }
		else if (lp->force & FORCE_AUI)	{lp->adapter_cnf |= A_CNF_MEDIA_AUI; }
		else if (lp->force & FORCE_BNC)	{lp->adapter_cnf |= A_CNF_MEDIA_10B_2; }
        }

	if (net_debug > 1)
		printk(KERN_DEBUG "%s: after force 0x%x, adapter_cnf=0x%x\n",
			dev->name, lp->force, lp->adapter_cnf);

        /* FIXME: We don't let you set dc-dc polarity or low RX squelch from the command line: add it here */

        /* FIXME: We don't let you set the IMM bit from the command line: add it to lp->auto_neg_cnf here */

        /* FIXME: we don't set the Ethernet address on the command line.  Use
           ifconfig IFACE hw ether AABBCCDDEEFF */

	printk(KERN_INFO "cs89x0 media %s%s%s",
	       (lp->adapter_cnf & A_CNF_10B_T)?"RJ-45,":"",
	       (lp->adapter_cnf & A_CNF_AUI)?"AUI,":"",
	       (lp->adapter_cnf & A_CNF_10B_2)?"BNC,":"");

	lp->irq_map = 0xffff;

	/* If this is a CS8900 then no pnp soft */
	if (lp->chip_type != CS8900 &&
	    /* Check if the ISA IRQ has been set  */
		(i = readreg(dev, PP_CS8920_ISAINT) & 0xff,
		 (i != 0 && i < CS8920_NO_INTS))) {
		if (!dev->irq)
			dev->irq = i;
	} else {
		i = lp->isa_config & INT_NO_MASK;
		if (lp->chip_type == CS8900) {
			/* Translate the IRQ using the IRQ mapping table. */
			if (i > sizeof(cs8900_irq_map)/sizeof(cs8900_irq_map[0]))
				printk("\ncs89x0: bug: isa_config is %d\n", i);
			else
				i = cs8900_irq_map[i];
			
			lp->irq_map = CS8900_IRQ_MAP; /* fixed IRQ map for CS8900 */
		} else {
			int irq_map_buff[IRQ_MAP_LEN/2];

			if (get_eeprom_data(dev, IRQ_MAP_EEPROM_DATA,
					    IRQ_MAP_LEN/2,
					    irq_map_buff) >= 0) {
				if ((irq_map_buff[0] & 0xff) == PNP_IRQ_FRMT)
					lp->irq_map = (irq_map_buff[0]>>8) | (irq_map_buff[1] << 8);
			}
		}
		if (!dev->irq)
			dev->irq = i;
	}

	printk(" IRQ %d", dev->irq);

#if ALLOW_DMA
	if (lp->use_dma) {
		get_dma_channel(dev);
		printk(", DMA %d", dev->dma);
	}
	else
#endif
	{
		printk(", programmed I/O");
	}

	/* print the ethernet address. */
	printk(", MAC ");
	for (i = 0; i < ETH_ALEN; i++)
	{
		printk("%s%02x", i ? ":" : "", dev->dev_addr[i]);
	}

	dev->open		= net_open;
	dev->stop		= net_close;
	dev->tx_timeout		= net_timeout;
	dev->watchdog_timeo	= HZ;
	dev->hard_start_xmit 	= net_send_packet;
	dev->get_stats		= net_get_stats;
	dev->set_multicast_list = set_multicast_list;
	dev->set_mac_address 	= set_mac_address;

	/* Fill in the fields of the device structure with ethernet values. */
	ether_setup(dev);

	printk("\n");
	if (net_debug)
		printk("cs89x0_probe1() successful\n");
	return 0;
out2:
	release_region(ioaddr & ~3, NETCARD_IO_EXTENT);
out1:
	kfree(dev->priv);
	dev->priv = 0;
out:
	return retval;
}


/*********************************
 * This page contains DMA routines
**********************************/

#if ALLOW_DMA

#define dma_page_eq(ptr1, ptr2) ((long)(ptr1)>>17 == (long)(ptr2)>>17)

static void
get_dma_channel(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	if (lp->dma) {
		dev->dma = lp->dma;
		lp->isa_config |= ISA_RxDMA;
	} else {
		if ((lp->isa_config & ANY_ISA_DMA) == 0)
			return;
		dev->dma = lp->isa_config & DMA_NO_MASK;
		if (lp->chip_type == CS8900)
			dev->dma += 5;
		if (dev->dma < 5 || dev->dma > 7) {
			lp->isa_config &= ~ANY_ISA_DMA;
			return;
		}
	}
	return;
}

static void
write_dma(struct net_device *dev, int chip_type, int dma)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	if ((lp->isa_config & ANY_ISA_DMA) == 0)
		return;
	if (chip_type == CS8900) {
		writereg(dev, PP_CS8900_ISADMA, dma-5);
	} else {
		writereg(dev, PP_CS8920_ISADMA, dma);
	}
}

static void
set_dma_cfg(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	if (lp->use_dma) {
		if ((lp->isa_config & ANY_ISA_DMA) == 0) {
			if (net_debug > 3)
				printk("set_dma_cfg(): no DMA\n");
			return;
		}
		if (lp->isa_config & ISA_RxDMA) {
			lp->curr_rx_cfg |= RX_DMA_ONLY;
			if (net_debug > 3)
				printk("set_dma_cfg(): RX_DMA_ONLY\n");
		} else {
			lp->curr_rx_cfg |= AUTO_RX_DMA;	/* not that we support it... */
			if (net_debug > 3)
				printk("set_dma_cfg(): AUTO_RX_DMA\n");
		}
	}
}

static int
dma_bufcfg(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	if (lp->use_dma)
		return (lp->isa_config & ANY_ISA_DMA)? RX_DMA_ENBL : 0;
	else
		return 0;
}

static int
dma_busctl(struct net_device *dev)
{
	int retval = 0;
	struct net_local *lp = (struct net_local *)dev->priv;
	if (lp->use_dma) {
		if (lp->isa_config & ANY_ISA_DMA)
			retval |= RESET_RX_DMA; /* Reset the DMA pointer */
		if (lp->isa_config & DMA_BURST)
			retval |= DMA_BURST_MODE; /* Does ISA config specify DMA burst ? */
		if (lp->dmasize == 64)
			retval |= RX_DMA_SIZE_64K; /* did they ask for 64K? */
		retval |= MEMORY_ON;	/* we need memory enabled to use DMA. */
	}
	return retval;
}

static void
dma_rx(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	struct sk_buff *skb;
	int status, length;
	unsigned char *bp = lp->rx_dma_ptr;

	status = bp[0] + (bp[1]<<8);
	length = bp[2] + (bp[3]<<8);
	bp += 4;
	if (net_debug > 5) {
		printk(	"%s: receiving DMA packet at %lx, status %x, length %x\n",
			dev->name, (unsigned long)bp, status, length);
	}
	if ((status & RX_OK) == 0) {
		count_rx_errors(status, lp);
		goto skip_this_frame;
	}

	/* Malloc up new buffer. */
	skb = dev_alloc_skb(length + 2);
	if (skb == NULL) {
		if (net_debug)	/* I don't think we want to do this to a stressed system */
			printk("%s: Memory squeeze, dropping packet.\n", dev->name);
		lp->stats.rx_dropped++;

		/* AKPM: advance bp to the next frame */
skip_this_frame:
		bp += (length + 3) & ~3;
		if (bp >= lp->end_dma_buff) bp -= lp->dmasize*1024;
		lp->rx_dma_ptr = bp;
		return;
	}
	skb_reserve(skb, 2);	/* longword align L3 header */
	skb->dev = dev;

	if (bp + length > lp->end_dma_buff) {
		int semi_cnt = lp->end_dma_buff - bp;
		memcpy(skb_put(skb,semi_cnt), bp, semi_cnt);
		memcpy(skb_put(skb,length - semi_cnt), lp->dma_buff,
		       length - semi_cnt);
	} else {
		memcpy(skb_put(skb,length), bp, length);
	}
	bp += (length + 3) & ~3;
	if (bp >= lp->end_dma_buff) bp -= lp->dmasize*1024;
	lp->rx_dma_ptr = bp;

	if (net_debug > 3) {
		printk(	"%s: received %d byte DMA packet of type %x\n",
			dev->name, length,
			(skb->data[ETH_ALEN+ETH_ALEN] << 8) | skb->data[ETH_ALEN+ETH_ALEN+1]);
	}
        skb->protocol=eth_type_trans(skb,dev);
	netif_rx(skb);
	dev->last_rx = jiffies;
	lp->stats.rx_packets++;
	lp->stats.rx_bytes += length;
}

#endif	/* ALLOW_DMA */

void  __init reset_chip(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int ioaddr = dev->base_addr;
	int reset_start_time;

	writereg(dev, PP_SelfCTL, readreg(dev, PP_SelfCTL) | POWER_ON_RESET);

	/* wait 30 ms */
	current->state = TASK_INTERRUPTIBLE;
	schedule_timeout(30*HZ/1000);

	if (lp->chip_type != CS8900) {
		/* Hardware problem requires PNP registers to be reconfigured after a reset */
		outw(PP_CS8920_ISAINT, ioaddr + ADD_PORT);
		outb(dev->irq, ioaddr + DATA_PORT);
		outb(0,      ioaddr + DATA_PORT + 1);

		outw(PP_CS8920_ISAMemB, ioaddr + ADD_PORT);
		outb((dev->mem_start >> 16) & 0xff, ioaddr + DATA_PORT);
		outb((dev->mem_start >> 8) & 0xff,   ioaddr + DATA_PORT + 1);
	}
	/* Wait until the chip is reset */
	reset_start_time = jiffies;
	while( (readreg(dev, PP_SelfST) & INIT_DONE) == 0 && jiffies - reset_start_time < 2)
		;
}


static void
control_dc_dc(struct net_device *dev, int on_not_off)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	unsigned int selfcontrol;
	int timenow = jiffies;
	/* control the DC to DC convertor in the SelfControl register.  
	   Note: This is hooked up to a general purpose pin, might not
	   always be a DC to DC convertor. */

	selfcontrol = HCB1_ENBL; /* Enable the HCB1 bit as an output */
	if (((lp->adapter_cnf & A_CNF_DC_DC_POLARITY) != 0) ^ on_not_off)
		selfcontrol |= HCB1;
	else
		selfcontrol &= ~HCB1;
	writereg(dev, PP_SelfCTL, selfcontrol);

	/* Wait for the DC/DC converter to power up - 500ms */
	while (jiffies - timenow < HZ)
		;
}

#define DETECTED_NONE  0
#define DETECTED_RJ45H 1
#define DETECTED_RJ45F 2
#define DETECTED_AUI   3
#define DETECTED_BNC   4

static int
detect_tp(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int timenow = jiffies;
	int fdx;

	if (net_debug > 1) printk("%s: Attempting TP\n", dev->name);

        /* If connected to another full duplex capable 10-Base-T card the link pulses
           seem to be lost when the auto detect bit in the LineCTL is set.
           To overcome this the auto detect bit will be cleared whilst testing the
           10-Base-T interface.  This would not be necessary for the sparrow chip but
           is simpler to do it anyway. */
	writereg(dev, PP_LineCTL, lp->linectl &~ AUI_ONLY);
	control_dc_dc(dev, 0);

        /* Delay for the hardware to work out if the TP cable is present - 150ms */
	for (timenow = jiffies; jiffies - timenow < 15; )
                ;
	if ((readreg(dev, PP_LineST) & LINK_OK) == 0)
		return DETECTED_NONE;

	if (lp->chip_type == CS8900) {
                switch (lp->force & 0xf0) {
#if 0
                case FORCE_AUTO:
			printk("%s: cs8900 doesn't autonegotiate\n",dev->name);
                        return DETECTED_NONE;
#endif
		/* CS8900 doesn't support AUTO, change to HALF*/
                case FORCE_AUTO:
			lp->force &= ~FORCE_AUTO;
                        lp->force |= FORCE_HALF;
			break;
		case FORCE_HALF:
			break;
                case FORCE_FULL:
			writereg(dev, PP_TestCTL, readreg(dev, PP_TestCTL) | FDX_8900);
			break;
                }
		fdx = readreg(dev, PP_TestCTL) & FDX_8900;
	} else {
		switch (lp->force & 0xf0) {
		case FORCE_AUTO:
			lp->auto_neg_cnf = AUTO_NEG_ENABLE;
			break;
		case FORCE_HALF:
			lp->auto_neg_cnf = 0;
			break;
		case FORCE_FULL:
			lp->auto_neg_cnf = RE_NEG_NOW | ALLOW_FDX;
			break;
                }

		writereg(dev, PP_AutoNegCTL, lp->auto_neg_cnf & AUTO_NEG_MASK);

		if ((lp->auto_neg_cnf & AUTO_NEG_BITS) == AUTO_NEG_ENABLE) {
			printk(KERN_INFO "%s: negotiating duplex...\n",dev->name);
			while (readreg(dev, PP_AutoNegST) & AUTO_NEG_BUSY) {
				if (jiffies - timenow > 4000) {
					printk(KERN_ERR "**** Full / half duplex auto-negotiation timed out ****\n");
					break;
				}
			}
		}
		fdx = readreg(dev, PP_AutoNegST) & FDX_ACTIVE;
	}
	if (fdx)
		return DETECTED_RJ45F;
	else
		return DETECTED_RJ45H;
}

/* send a test packet - return true if carrier bits are ok */
static int
send_test_pkt(struct net_device *dev)
{
	char test_packet[] = { 0,0,0,0,0,0, 0,0,0,0,0,0,
				 0, 46, /* A 46 in network order */
				 0, 0, /* DSAP=0 & SSAP=0 fields */
				 0xf3, 0 /* Control (Test Req + P bit set) */ };
	long timenow = jiffies;

	writereg(dev, PP_LineCTL, readreg(dev, PP_LineCTL) | SERIAL_TX_ON);

	memcpy(test_packet,          dev->dev_addr, ETH_ALEN);
	memcpy(test_packet+ETH_ALEN, dev->dev_addr, ETH_ALEN);

        writeword(dev, TX_CMD_PORT, TX_AFTER_ALL);
        writeword(dev, TX_LEN_PORT, ETH_ZLEN);

	/* Test to see if the chip has allocated memory for the packet */
	while (jiffies - timenow < 5)
		if (readreg(dev, PP_BusST) & READY_FOR_TX_NOW)
			break;
	if (jiffies - timenow >= 5)
		return 0;	/* this shouldn't happen */

	/* Write the contents of the packet */
	outsw(dev->base_addr + TX_FRAME_PORT,test_packet,(ETH_ZLEN+1) >>1);

	if (net_debug > 1) printk("Sending test packet ");
	/* wait a couple of jiffies for packet to be received */
	for (timenow = jiffies; jiffies - timenow < 3; )
                ;
        if ((readreg(dev, PP_TxEvent) & TX_SEND_OK_BITS) == TX_OK) {
                if (net_debug > 1) printk("succeeded\n");
                return 1;
        }
	if (net_debug > 1) printk("failed\n");
	return 0;
}


static int
detect_aui(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	if (net_debug > 1) printk("%s: Attempting AUI\n", dev->name);
	control_dc_dc(dev, 0);

	writereg(dev, PP_LineCTL, (lp->linectl &~ AUTO_AUI_10BASET) | AUI_ONLY);

	if (send_test_pkt(dev))
		return DETECTED_AUI;
	else
		return DETECTED_NONE;
}

static int
detect_bnc(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	if (net_debug > 1) printk("%s: Attempting BNC\n", dev->name);
	control_dc_dc(dev, 1);

	writereg(dev, PP_LineCTL, (lp->linectl &~ AUTO_AUI_10BASET) | AUI_ONLY);

	if (send_test_pkt(dev))
		return DETECTED_BNC;
	else
		return DETECTED_NONE;
}


static void
write_irq(struct net_device *dev, int chip_type, int irq)
{
	int i;

	if (chip_type == CS8900) {
		/* Search the mapping table for the corresponding IRQ pin. */
		for (i = 0; i != sizeof(cs8900_irq_map)/sizeof(cs8900_irq_map[0]); i++)
			if (cs8900_irq_map[i] == irq)
				break;
		/* Not found */
		if (i == sizeof(cs8900_irq_map)/sizeof(cs8900_irq_map[0]))
			i = 3;
		writereg(dev, PP_CS8900_ISAINT, i);
	} else {
		writereg(dev, PP_CS8920_ISAINT, irq);
	}
}

/* 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.
   */

/* AKPM: do we need to do any locking here? */

static int
net_open(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	int result = 0;
	int i;
	int ret;

	if (dev->irq < 2) {
		/* Allow interrupts to be generated by the chip */
/* Cirrus' release had this: */
#if 0
		writereg(dev, PP_BusCTL, readreg(dev, PP_BusCTL)|ENABLE_IRQ );
#endif
/* And 2.3.47 had this: */
		writereg(dev, PP_BusCTL, ENABLE_IRQ | MEMORY_ON);

		for (i = 2; i < CS8920_NO_INTS; i++) {
			if ((1 << dev->irq) & lp->irq_map) {
				if (request_irq(i, net_interrupt, 0, dev->name, dev) == 0) {
					dev->irq = i;
					write_irq(dev, lp->chip_type, i);
					/* writereg(dev, PP_BufCFG, GENERATE_SW_INTERRUPT); */
					break;
				}
			}
		}

		if (i >= CS8920_NO_INTS) {
			writereg(dev, PP_BusCTL, 0);	/* disable interrupts. */
			printk(KERN_ERR "cs89x0: can't get an interrupt\n");
			ret = -EAGAIN;
			goto bad_out;
		}
	} else {
		if (((1 << dev->irq) & lp->irq_map) == 0) {
			printk(KERN_ERR "%s: IRQ %d is not in our map of allowable IRQs, which is %x\n",
                               dev->name, dev->irq, lp->irq_map);
			ret = -EAGAIN;
			goto bad_out;
		}
/* FIXME: Cirrus' release had this: */
		writereg(dev, PP_BusCTL, readreg(dev, PP_BusCTL)|ENABLE_IRQ );
/* And 2.3.47 had this: */
#if 0
		writereg(dev, PP_BusCTL, ENABLE_IRQ | MEMORY_ON);
#endif
		write_irq(dev, lp->chip_type, dev->irq);
		ret = request_irq(dev->irq, &net_interrupt, 0, dev->name, dev);
		if (ret) {
			if (net_debug)
				printk(KERN_DEBUG "cs89x0: request_irq(%d) failed\n", dev->irq);
			goto bad_out;
		}
	}

#if ALLOW_DMA
	if (lp->use_dma) {
		if (lp->isa_config & ANY_ISA_DMA) {
			unsigned long flags;
			lp->dma_buff = (unsigned char *)__get_dma_pages(GFP_KERNEL,
							get_order(lp->dmasize * 1024));

			if (!lp->dma_buff) {
				printk(KERN_ERR "%s: cannot get %dK memory for DMA\n", dev->name, lp->dmasize);
				goto release_irq;
			}
			if (net_debug > 1) {
				printk(	"%s: dma %lx %lx\n",
					dev->name,
					(unsigned long)lp->dma_buff,
					(unsigned long)virt_to_bus(lp->dma_buff));
			}
			if ((unsigned long)virt_to_bus(lp->dma_buff) >= MAX_DMA_ADDRESS ||
			    !dma_page_eq(lp->dma_buff, lp->dma_buff+lp->dmasize*1024-1)) {
				printk(KERN_ERR "%s: not usable as DMA buffer\n", dev->name);
				goto release_irq;
			}
			memset(lp->dma_buff, 0, lp->dmasize * 1024);	/* Why? */
			if (request_dma(dev->dma, dev->name)) {
				printk(KERN_ERR "%s: cannot get dma channel %d\n", dev->name, dev->dma);
				goto release_irq;
			}
			write_dma(dev, lp->chip_type, dev->dma);
			lp->rx_dma_ptr = lp->dma_buff;
			lp->end_dma_buff = lp->dma_buff + lp->dmasize*1024;
			spin_lock_irqsave(&lp->lock, flags);
			disable_dma(dev->dma);
			clear_dma_ff(dev->dma);
			set_dma_mode(dev->dma, 0x14); /* auto_init as well */
			set_dma_addr(dev->dma, virt_to_bus(lp->dma_buff));
			set_dma_count(dev->dma, lp->dmasize*1024);
			enable_dma(dev->dma);
			spin_unlock_irqrestore(&lp->lock, flags);
		}
	}
#endif	/* ALLOW_DMA */

	/* set the Ethernet address */
	for (i=0; i < ETH_ALEN/2; i++)
		writereg(dev, PP_IA+i*2, dev->dev_addr[i*2] | (dev->dev_addr[i*2+1] << 8));

	/* while we're testing the interface, leave interrupts disabled */
	writereg(dev, PP_BusCTL, MEMORY_ON);

	/* Set the LineCTL quintuplet based on adapter configuration read from EEPROM */
	if ((lp->adapter_cnf & A_CNF_EXTND_10B_2) && (lp->adapter_cnf & A_CNF_LOW_RX_SQUELCH))
                lp->linectl = LOW_RX_SQUELCH;
	else
                lp->linectl = 0;

        /* check to make sure that they have the "right" hardware available */
	switch(lp->adapter_cnf & A_CNF_MEDIA_TYPE) {
	case A_CNF_MEDIA_10B_T: result = lp->adapter_cnf & A_CNF_10B_T; break;
	case A_CNF_MEDIA_AUI:   result = lp->adapter_cnf & A_CNF_AUI; break;
	case A_CNF_MEDIA_10B_2: result = lp->adapter_cnf & A_CNF_10B_2; break;
        default: result = lp->adapter_cnf & (A_CNF_10B_T | A_CNF_AUI | A_CNF_10B_2);
        }
        if (!result) {
                printk(KERN_ERR "%s: EEPROM is configured for unavailable media\n", dev->name);
        release_irq:
#if ALLOW_DMA
		release_dma_buff(lp);
#endif
                writereg(dev, PP_LineCTL, readreg(dev, PP_LineCTL) & ~(SERIAL_TX_ON | SERIAL_RX_ON));
                free_irq(dev->irq, dev);
		ret = -EAGAIN;
		goto bad_out;
	}

        /* set the hardware to the configured choice */
	switch(lp->adapter_cnf & A_CNF_MEDIA_TYPE) {
	case A_CNF_MEDIA_10B_T:
                result = detect_tp(dev);
                if (result==DETECTED_NONE) {
                        printk(KERN_WARNING "%s: 10Base-T (RJ-45) has no cable\n", dev->name);
                        if (lp->auto_neg_cnf & IMM_BIT) /* check "ignore missing media" bit */
                                result = DETECTED_RJ45H; /* Yes! I don't care if I see a link pulse */
                }
		break;
	case A_CNF_MEDIA_AUI:
                result = detect_aui(dev);
                if (result==DETECTED_NONE) {
                        printk(KERN_WARNING "%s: 10Base-5 (AUI) has no cable\n", dev->name);
                        if (lp->auto_neg_cnf & IMM_BIT) /* check "ignore missing media" bit */
                                result = DETECTED_AUI; /* Yes! I don't care if I see a carrrier */
                }
		break;
	case A_CNF_MEDIA_10B_2:
                result = detect_bnc(dev);
                if (result==DETECTED_NONE) {
                        printk(KERN_WARNING "%s: 10Base-2 (BNC) has no cable\n", dev->name);
                        if (lp->auto_neg_cnf & IMM_BIT) /* check "ignore missing media" bit */
                                result = DETECTED_BNC; /* Yes! I don't care if I can xmit a packet */
                }
		break;
	case A_CNF_MEDIA_AUTO:
		writereg(dev, PP_LineCTL, lp->linectl | AUTO_AUI_10BASET);
		if (lp->adapter_cnf & A_CNF_10B_T)
			if ((result = detect_tp(dev)) != DETECTED_NONE)
				break;
		if (lp->adapter_cnf & A_CNF_AUI)
			if ((result = detect_aui(dev)) != DETECTED_NONE)
				break;
		if (lp->adapter_cnf & A_CNF_10B_2)
			if ((result = detect_bnc(dev)) != DETECTED_NONE)
				break;
		printk(KERN_ERR "%s: no media detected\n", dev->name);
                goto release_irq;
	}
	switch(result) {
	case DETECTED_NONE:
		printk(KERN_ERR "%s: no network cable attached to configured media\n", dev->name);
                goto release_irq;
	case DETECTED_RJ45H:
		printk(KERN_INFO "%s: using half-duplex 10Base-T (RJ-45)\n", dev->name);
		break;
	case DETECTED_RJ45F:
		printk(KERN_INFO "%s: using full-duplex 10Base-T (RJ-45)\n", dev->name);
		break;
	case DETECTED_AUI:
		printk(KERN_INFO "%s: using 10Base-5 (AUI)\n", dev->name);
		break;
	case DETECTED_BNC:
		printk(KERN_INFO "%s: using 10Base-2 (BNC)\n", dev->name);
		break;
	}

	/* Turn on both receive and transmit operations */
	writereg(dev, PP_LineCTL, readreg(dev, PP_LineCTL) | SERIAL_RX_ON | SERIAL_TX_ON);

	/* Receive only error free packets addressed to this card */
	lp->rx_mode = 0;
	writereg(dev, PP_RxCTL, DEF_RX_ACCEPT);

	lp->curr_rx_cfg = RX_OK_ENBL | RX_CRC_ERROR_ENBL;

	if (lp->isa_config & STREAM_TRANSFER)
		lp->curr_rx_cfg |= RX_STREAM_ENBL;
#if ALLOW_DMA
	set_dma_cfg(dev);
#endif
	writereg(dev, PP_RxCFG, lp->curr_rx_cfg);

	writereg(dev, PP_TxCFG, TX_LOST_CRS_ENBL | TX_SQE_ERROR_ENBL | TX_OK_ENBL |
		TX_LATE_COL_ENBL | TX_JBR_ENBL | TX_ANY_COL_ENBL | TX_16_COL_ENBL);

	writereg(dev, PP_BufCFG, READY_FOR_TX_ENBL | RX_MISS_COUNT_OVRFLOW_ENBL |
#if ALLOW_DMA
		dma_bufcfg(dev) |
#endif
		TX_COL_COUNT_OVRFLOW_ENBL | TX_UNDERRUN_ENBL);

	/* now that we've got our act together, enable everything */
	writereg(dev, PP_BusCTL, ENABLE_IRQ
		 | (dev->mem_start?MEMORY_ON : 0) /* turn memory on */
#if ALLOW_DMA
		 | dma_busctl(dev)
#endif
                 );
        netif_start_queue(dev);
	if (net_debug > 1)
		printk("cs89x0: net_open() succeeded\n");
	return 0;
bad_out:
	return ret;
}

static void net_timeout(struct net_device *dev)
{
	/* If we get here, some higher level has decided we are broken.
	   There should really be a "kick me" function call instead. */
	if (net_debug > 0) printk("%s: transmit timed out, %s?\n", dev->name,
		   tx_done(dev) ? "IRQ conflict ?" : "network cable problem");
	/* Try to restart the adaptor. */
	netif_wake_queue(dev);
}

static int net_send_packet(struct sk_buff *skb, struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	if (net_debug > 3) {
		printk("%s: sent %d byte packet of type %x\n",
			dev->name, skb->len,
			(skb->data[ETH_ALEN+ETH_ALEN] << 8) | skb->data[ETH_ALEN+ETH_ALEN+1]);
	}

	/* keep the upload from being interrupted, since we
                  ask the chip to start transmitting before the
                  whole packet has been completely uploaded. */

	spin_lock_irq(&lp->lock);
	netif_stop_queue(dev);

	/* initiate a transmit sequence */
	writeword(dev, TX_CMD_PORT, lp->send_cmd);
	writeword(dev, TX_LEN_PORT, skb->len);

	/* Test to see if the chip has allocated memory for the packet */
	if ((readreg(dev, PP_BusST) & READY_FOR_TX_NOW) == 0) {
		/*
		 * Gasp!  It hasn't.  But that shouldn't happen since
		 * we're waiting for TxOk, so return 1 and requeue this packet.
		 */
		
		spin_unlock_irq(&lp->lock);
		if (net_debug) printk("cs89x0: Tx buffer not free!\n");
		return 1;
	}
	/* Write the contents of the packet */
	outsw(dev->base_addr + TX_FRAME_PORT,skb->data,(skb->len+1) >>1);
	spin_unlock_irq(&lp->lock);
	dev->trans_start = jiffies;
	dev_kfree_skb (skb);

	/*
	 * We DO NOT call netif_wake_queue() here.
	 * We also DO NOT call netif_start_queue().
	 *
	 * Either of these would cause another bottom half run through
	 * net_send_packet() before this packet has fully gone out.  That causes
	 * us to hit the "Gasp!" above and the send is rescheduled.  it runs like
	 * a dog.  We just return and wait for the Tx completion interrupt handler
	 * to restart the netdevice layer
	 */

	return 0;
}

/* The typical workload of the driver:
   Handle the network interface interrupts. */
   
static void net_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
	struct net_device *dev = dev_id;
	struct net_local *lp;
	int ioaddr, status;
 
	ioaddr = dev->base_addr;
	lp = (struct net_local *)dev->priv;

	/* we MUST read all the events out of the ISQ, otherwise we'll never
           get interrupted again.  As a consequence, we can't have any limit
           on the number of times we loop in the interrupt handler.  The
           hardware guarantees that eventually we'll run out of events.  Of
           course, if you're on a slow machine, and packets are arriving
           faster than you can read them off, you're screwed.  Hasta la
           vista, baby!  */
	while ((status = readword(dev, ISQ_PORT))) {
		if (net_debug > 4)printk("%s: event=%04x\n", dev->name, status);
		switch(status & ISQ_EVENT_MASK) {
		case ISQ_RECEIVER_EVENT:
			/* Got a packet(s). */
			net_rx(dev);
			break;
		case ISQ_TRANSMITTER_EVENT:
			lp->stats.tx_packets++;
			netif_wake_queue(dev);	/* Inform upper layers. */
			if ((status & (	TX_OK |
					TX_LOST_CRS |
					TX_SQE_ERROR |
					TX_LATE_COL |
					TX_16_COL)) != TX_OK) {
				if ((status & TX_OK) == 0) lp->stats.tx_errors++;
				if (status & TX_LOST_CRS) lp->stats.tx_carrier_errors++;
				if (status & TX_SQE_ERROR) lp->stats.tx_heartbeat_errors++;
				if (status & TX_LATE_COL) lp->stats.tx_window_errors++;
				if (status & TX_16_COL) lp->stats.tx_aborted_errors++;
			}
			break;
		case ISQ_BUFFER_EVENT:
			if (status & READY_FOR_TX) {
				/* we tried to transmit a packet earlier,
                                   but inexplicably ran out of buffers.
                                   That shouldn't happen since we only ever
                                   load one packet.  Shrug.  Do the right
                                   thing anyway. */
				netif_wake_queue(dev);	/* Inform upper layers. */
			}
			if (status & TX_UNDERRUN) {
				if (net_debug > 0) printk("%s: transmit underrun\n", dev->name);
                                lp->send_underrun++;
                                if (lp->send_underrun == 3) lp->send_cmd = TX_AFTER_381;
                                else if (lp->send_underrun == 6) lp->send_cmd = TX_AFTER_ALL;
				/* transmit cycle is done, although
				   frame wasn't transmitted - this
				   avoids having to wait for the upper
				   layers to timeout on us, in the
				   event of a tx underrun */
				netif_wake_queue(dev);	/* Inform upper layers. */
                        }
#if ALLOW_DMA
			if (lp->use_dma && (status & RX_DMA)) {
				int count = readreg(dev, PP_DmaFrameCnt);
				while(count) {
					if (net_debug > 5)
						printk("%s: receiving %d DMA frames\n", dev->name, count);
					if (net_debug > 2 && count >1)
						printk("%s: receiving %d DMA frames\n", dev->name, count);
					dma_rx(dev);
					if (--count == 0)
						count = readreg(dev, PP_DmaFrameCnt);
					if (net_debug > 2 && count > 0)
						printk("%s: continuing with %d DMA frames\n", dev->name, count);
				}
			}
#endif
			break;
		case ISQ_RX_MISS_EVENT:
			lp->stats.rx_missed_errors += (status >>6);
			break;
		case ISQ_TX_COL_EVENT:
			lp->stats.collisions += (status >>6);
			break;
		}
	}
}

static void
count_rx_errors(int status, struct net_local *lp)
{
	lp->stats.rx_errors++;
	if (status & RX_RUNT) lp->stats.rx_length_errors++;
	if (status & RX_EXTRA_DATA) lp->stats.rx_length_errors++;
	if (status & RX_CRC_ERROR) if (!(status & (RX_EXTRA_DATA|RX_RUNT)))
		/* per str 172 */
		lp->stats.rx_crc_errors++;
	if (status & RX_DRIBBLE) lp->stats.rx_frame_errors++;
	return;
}

/* We have a good packet(s), get it/them out of the buffers. */
static void
net_rx(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	struct sk_buff *skb;
	int status, length;

	int ioaddr = dev->base_addr;
	status = inw(ioaddr + RX_FRAME_PORT);
	length = inw(ioaddr + RX_FRAME_PORT);

	if ((status & RX_OK) == 0) {
		count_rx_errors(status, lp);
		return;
	}

	/* Malloc up new buffer. */
	skb = dev_alloc_skb(length + 2);
	if (skb == NULL) {
#if 0		/* Again, this seems a cruel thing to do */
		printk(KERN_WARNING "%s: Memory squeeze, dropping packet.\n", dev->name);
#endif
		lp->stats.rx_dropped++;
		return;
	}
	skb_reserve(skb, 2);	/* longword align L3 header */
	skb->dev = dev;

	insw(ioaddr + RX_FRAME_PORT, skb_put(skb, length), length >> 1);
	if (length & 1)
		skb->data[length-1] = inw(ioaddr + RX_FRAME_PORT);

	if (net_debug > 3) {
		printk(	"%s: received %d byte packet of type %x\n",
			dev->name, length,
			(skb->data[ETH_ALEN+ETH_ALEN] << 8) | skb->data[ETH_ALEN+ETH_ALEN+1]);
	}

        skb->protocol=eth_type_trans(skb,dev);
	netif_rx(skb);
	dev->last_rx = jiffies;
	lp->stats.rx_packets++;
	lp->stats.rx_bytes += length;
}

#if ALLOW_DMA
static void release_dma_buff(struct net_local *lp)
{
	if (lp->dma_buff) {
		free_pages((unsigned long)(lp->dma_buff), get_order(lp->dmasize * 1024));
		lp->dma_buff = 0;
	}
}
#endif

/* The inverse routine to net_open(). */
static int
net_close(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;

	netif_stop_queue(dev);
	
	writereg(dev, PP_RxCFG, 0);
	writereg(dev, PP_TxCFG, 0);
	writereg(dev, PP_BufCFG, 0);
	writereg(dev, PP_BusCTL, 0);

	free_irq(dev->irq, dev);

#if ALLOW_DMA
	if (lp->use_dma && lp->dma) {
		free_dma(dev->dma);
		release_dma_buff(lp);
	}
#endif

	/* Update the statistics here. */
	return 0;
}

/* Get the current statistics.	This may be called with the card open or
   closed. */
static struct net_device_stats *
net_get_stats(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	unsigned long flags;

	spin_lock_irqsave(&lp->lock, flags);
	/* Update the statistics from the device registers. */
	lp->stats.rx_missed_errors += (readreg(dev, PP_RxMiss) >> 6);
	lp->stats.collisions += (readreg(dev, PP_TxCol) >> 6);
	spin_unlock_irqrestore(&lp->lock, flags);

	return &lp->stats;
}

static void set_multicast_list(struct net_device *dev)
{
	struct net_local *lp = (struct net_local *)dev->priv;
	unsigned long flags;

	spin_lock_irqsave(&lp->lock, flags);
	if(dev->flags&IFF_PROMISC)
	{
		lp->rx_mode = RX_ALL_ACCEPT;
	}
	else if((dev->flags&IFF_ALLMULTI)||dev->mc_list)
	{
		/* The multicast-accept list is initialized to accept-all, and we
		   rely on higher-level filtering for now. */
		lp->rx_mode = RX_MULTCAST_ACCEPT;
	} 
	else
		lp->rx_mode = 0;

	writereg(dev, PP_RxCTL, DEF_RX_ACCEPT | lp->rx_mode);

	/* in promiscuous mode, we accept errored packets, so we have to enable interrupts on them also */
	writereg(dev, PP_RxCFG, lp->curr_rx_cfg |
	     (lp->rx_mode == RX_ALL_ACCEPT? (RX_CRC_ERROR_ENBL|RX_RUNT_ENBL|RX_EXTRA_DATA_ENBL) : 0));
	spin_unlock_irqrestore(&lp->lock, flags);
}


static int set_mac_address(struct net_device *dev, void *addr)
{
	int i;

	if (netif_running(dev))
		return -EBUSY;
	if (net_debug) {
		printk("%s: Setting MAC address to ", dev->name);
		for (i = 0; i < 6; i++)
			printk(" %2.2x", dev->dev_addr[i] = ((unsigned char *)addr)[i]);
		printk(".\n");
	}
	/* set the Ethernet address */
	for (i=0; i < ETH_ALEN/2; i++)
		writereg(dev, PP_IA+i*2, dev->dev_addr[i*2] | (dev->dev_addr[i*2+1] << 8));

	return 0;
}

#ifdef MODULE

static struct net_device dev_cs89x0 = {
        "",
        0, 0, 0, 0,
        0, 0,
        0, 0, 0, NULL, NULL };

/*
 * Support the 'debug' module parm even if we're compiled for non-debug to 
 * avoid breaking someone's startup scripts 
 */

static int io;
static int irq;
static int debug;
static char media[8];
static int duplex=-1;

static int use_dma;			/* These generate unused var warnings if ALLOW_DMA = 0 */
static int dma;
static int dmasize=16;			/* or 64 */

MODULE_PARM(io, "i");
MODULE_PARM(irq, "i");
MODULE_PARM(debug, "i");
MODULE_PARM(media, "c8");
MODULE_PARM(duplex, "i");
MODULE_PARM(dma , "i");
MODULE_PARM(dmasize , "i");
MODULE_PARM(use_dma , "i");
MODULE_PARM_DESC(io, "cs89x0 I/O base address");
MODULE_PARM_DESC(irq, "cs89x0 IRQ number");
#if DEBUGGING
MODULE_PARM_DESC(debug, "cs89x0 debug level (0-6)");
#else
MODULE_PARM_DESC(debug, "(ignored)");
#endif
MODULE_PARM_DESC(media, "Set cs89x0 adapter(s) media type(s) (rj45,bnc,aui)");
/* No other value than -1 for duplex seems to be currently interpreted */
MODULE_PARM_DESC(duplex, "(ignored)");
#if ALLOW_DMA
MODULE_PARM_DESC(dma , "cs89x0 ISA DMA channel; ignored if use_dma=0");
MODULE_PARM_DESC(dmasize , "cs89x0 DMA size in kB (16,64); ignored if use_dma=0");
MODULE_PARM_DESC(use_dma , "cs89x0 using DMA (0-1)");
#else
MODULE_PARM_DESC(dma , "(ignored)");
MODULE_PARM_DESC(dmasize , "(ignored)");
MODULE_PARM_DESC(use_dma , "(ignored)");
#endif

MODULE_AUTHOR("Mike Cruse, Russwll Nelson <nelson@crynwr.com>, Andrew Morton <andrewm@uow.edu.au>");

EXPORT_NO_SYMBOLS;

/*
* media=t             - specify media type
   or media=2
   or media=aui
   or medai=auto
* duplex=0            - specify forced half/full/autonegotiate duplex
* debug=#             - debug level


* Default Chip Configuration:
  * DMA Burst = enabled
  * IOCHRDY Enabled = enabled
    * UseSA = enabled
    * CS8900 defaults to half-duplex if not specified on command-line
    * CS8920 defaults to autoneg if not specified on command-line
    * Use reset defaults for other config parameters

* Assumptions:
  * media type specified is supported (circuitry is present)
  * if memory address is > 1MB, then required mem decode hw is present
  * if 10B-2, then agent other than driver will enable DC/DC converter
    (hw or software util)


*/

int
init_module(void)
{
	struct net_local *lp;
	int ret = 0;

#if DEBUGGING
	net_debug = debug;
#else
	debug = 0;
#endif

	dev_cs89x0.irq = irq;
	dev_cs89x0.base_addr = io;

        dev_cs89x0.init = cs89x0_probe;
        dev_cs89x0.priv = kmalloc(sizeof(struct net_local), GFP_KERNEL);
	if (dev_cs89x0.priv == 0) {
		printk(KERN_ERR "cs89x0.c: Out of memory.\n");
		return -ENOMEM;
	}
	memset(dev_cs89x0.priv, 0, sizeof(struct net_local));
	lp = (struct net_local *)dev_cs89x0.priv;

#if ALLOW_DMA
	if (use_dma) {
		lp->use_dma = use_dma;
		lp->dma = dma;
		lp->dmasize = dmasize;
	}
#endif

	spin_lock_init(&lp->lock);

        /* boy, they'd better get these right */
        if (!strcmp(media, "rj45"))
		lp->adapter_cnf = A_CNF_MEDIA_10B_T | A_CNF_10B_T;
	else if (!strcmp(media, "aui"))
		lp->adapter_cnf = A_CNF_MEDIA_AUI   | A_CNF_AUI;
	else if (!strcmp(media, "bnc"))
		lp->adapter_cnf = A_CNF_MEDIA_10B_2 | A_CNF_10B_2;
	else
		lp->adapter_cnf = A_CNF_MEDIA_10B_T | A_CNF_10B_T;

        if (duplex==-1)
		lp->auto_neg_cnf = AUTO_NEG_ENABLE;

        if (io == 0) {
                printk(KERN_ERR "cs89x0.c: Module autoprobing not allowed.\n");
                printk(KERN_ERR "cs89x0.c: Append io=0xNNN\n");
                ret = -EPERM;
		goto out;
        }

#if ALLOW_DMA
	if (use_dma && dmasize != 16 && dmasize != 64) {
		printk(KERN_ERR "cs89x0.c: dma size must be either 16K or 64K, not %dK\n", dmasize);
		ret = -EPERM;
		goto out;
	}
#endif

        if (register_netdev(&dev_cs89x0) != 0) {
                printk(KERN_ERR "cs89x0.c: No card found at 0x%x\n", io);
                ret = -ENXIO;
		goto out;
        }
out:
	if (ret)
		kfree(dev_cs89x0.priv);
	return ret;
}

void
cleanup_module(void)
{
        if (dev_cs89x0.priv != NULL) {
                /* Free up the private structure, or leak memory :-)  */
                unregister_netdev(&dev_cs89x0);
		outw(PP_ChipID, dev_cs89x0.base_addr + ADD_PORT);
                kfree(dev_cs89x0.priv);
                dev_cs89x0.priv = NULL;	/* gets re-allocated by cs89x0_probe1 */
                /* If we don't do this, we can't re-insmod it later. */
                release_region(dev_cs89x0.base_addr, NETCARD_IO_EXTENT);
        }
}
#endif /* MODULE */

/*
 * Local variables:
 *  version-control: t
 *  kept-new-versions: 5
 *  c-indent-level: 8
 *  tab-width: 8
 * End:
 *
 */
