sbni.c

linux-2.6.15.6

/* sbni.c:  Granch SBNI12 leased line adapters driver for linux
 *
 *	Written 2001 by Denis I.Timofeev ([e-mail])
 *
 *	Previous versions were written by Yaroslav Polyakov,
 *	Alexey Zverev and Max Khon.
 *
 *	Driver supports SBNI12-02,-04,-05,-10,-11 cards, single and
 *	double-channel, PCI and ISA modifications.
 *	More info and useful utilities to work with SBNI12 cards you can find
 *	at http://www.granch.com (English) or http://www.granch.ru (Russian)
 *
 *	This software may be used and distributed according to the terms
 *	of the GNU General Public License.
 *
 *
 *  5.0.1	Jun 22 2001
 *	  - Fixed bug in probe
 *  5.0.0	Jun 06 2001
 *	  - Driver was completely redesigned by Denis I.Timofeev,
 *	  - now PCI/Dual, ISA/Dual (with single interrupt line) models are
 *	  - supported
 *  3.3.0	Thu Feb 24 21:30:28 NOVT 2000 
 *        - PCI cards support
 *  3.2.0	Mon Dec 13 22:26:53 NOVT 1999
 * 	  - Completely rebuilt all the packet storage system
 * 	  -    to work in Ethernet-like style.
 *  3.1.1	just fixed some bugs (5 aug 1999)
 *  3.1.0	added balancing feature	(26 apr 1999)
 *  3.0.1	just fixed some bugs (14 apr 1999).
 *  3.0.0	Initial Revision, Yaroslav Polyakov (24 Feb 1999)
 *        - added pre-calculation for CRC, fixed bug with "len-2" frames, 
 *        - removed outbound fragmentation (MTU=1000), written CRC-calculation 
 *        - on asm, added work with hard_headers and now we have our own cache 
 *        - for them, optionally supported word-interchange on some chipsets,
 * 
 *	Known problem: this driver wasn't tested on multiprocessor machine.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/fcntl.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/pci.h>
#include <linux/skbuff.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/delay.h>

#include <net/arp.h>

#include <asm/io.h>
#include <asm/types.h>
#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>

#include "sbni.h"

/* device private data */

struct net_local {
	struct net_device_stats	stats;
	struct timer_list	watchdog;

	spinlock_t	lock;
	struct sk_buff  *rx_buf_p;		/* receive buffer ptr */
	struct sk_buff  *tx_buf_p;		/* transmit buffer ptr */
	
	unsigned int	framelen;		/* current frame length */
	unsigned int	maxframe;		/* maximum valid frame length */
	unsigned int	state;
	unsigned int	inppos, outpos;		/* positions in rx/tx buffers */

	/* transmitting frame number - from frames qty to 1 */
	unsigned int	tx_frameno;

	/* expected number of next receiving frame */
	unsigned int	wait_frameno;

	/* count of failed attempts to frame send - 32 attempts do before
	   error - while receiver tunes on opposite side of wire */
	unsigned int	trans_errors;

	/* idle time; send pong when limit exceeded */
	unsigned int	timer_ticks;

	/* fields used for receive level autoselection */
	int	delta_rxl;
	unsigned int	cur_rxl_index, timeout_rxl;
	unsigned long	cur_rxl_rcvd, prev_rxl_rcvd;

	struct sbni_csr1	csr1;		/* current value of CSR1 */
	struct sbni_in_stats	in_stats; 	/* internal statistics */ 

	struct net_device		*second;	/* for ISA/dual cards */

#ifdef CONFIG_SBNI_MULTILINE
	struct net_device		*master;
	struct net_device		*link;
#endif
};


static int  sbni_card_probe( unsigned long );
static int  sbni_pci_probe( struct net_device  * );
static struct net_device  *sbni_probe1(struct net_device *, unsigned long, int);
static int  sbni_open( struct net_device * );
static int  sbni_close( struct net_device * );
static int  sbni_start_xmit( struct sk_buff *, struct net_device * );
static int  sbni_ioctl( struct net_device *, struct ifreq *, int );
static struct net_device_stats  *sbni_get_stats( struct net_device * );
static void  set_multicast_list( struct net_device * );

static irqreturn_t sbni_interrupt( int, void *, struct pt_regs * );
static void  handle_channel( struct net_device * );
static int   recv_frame( struct net_device * );
static void  send_frame( struct net_device * );
static int   upload_data( struct net_device *,
			  unsigned, unsigned, unsigned, u32 );
static void  download_data( struct net_device *, u32 * );
static void  sbni_watchdog( unsigned long );
static void  interpret_ack( struct net_device *, unsigned );
static int   append_frame_to_pkt( struct net_device *, unsigned, u32 );
static void  indicate_pkt( struct net_device * );
static void  card_start( struct net_device * );
static void  prepare_to_send( struct sk_buff *, struct net_device * );
static void  drop_xmit_queue( struct net_device * );
static void  send_frame_header( struct net_device *, u32 * );
static int   skip_tail( unsigned int, unsigned int, u32 );
static int   check_fhdr( u32, u32 *, u32 *, u32 *, u32 *, u32 * );
static void  change_level( struct net_device * );
static void  timeout_change_level( struct net_device * );
static u32   calc_crc32( u32, u8 *, u32 );
static struct sk_buff *  get_rx_buf( struct net_device * );
static int  sbni_init( struct net_device * );

#ifdef CONFIG_SBNI_MULTILINE
static int  enslave( struct net_device *, struct net_device * );
static int  emancipate( struct net_device * );
#endif

#ifdef __i386__
#define ASM_CRC 1
#endif

static const char  version[] =
	"Granch SBNI12 driver ver 5.0.1  Jun 22 2001  Denis I.Timofeev.\n";

static int  skip_pci_probe	__initdata = 0;
static int  scandone	__initdata = 0;
static int  num		__initdata = 0;

static unsigned char  rxl_tab[];
static u32  crc32tab[];

/* A list of all installed devices, for removing the driver module. */
static struct net_device  *sbni_cards[ SBNI_MAX_NUM_CARDS ];

/* Lists of device's parameters */
static u32	io[   SBNI_MAX_NUM_CARDS ] __initdata =
	{ [0 ... SBNI_MAX_NUM_CARDS-1] = -1 };
static u32	irq[  SBNI_MAX_NUM_CARDS ] __initdata;
static u32	baud[ SBNI_MAX_NUM_CARDS ] __initdata;
static u32	rxl[  SBNI_MAX_NUM_CARDS ] __initdata =
	{ [0 ... SBNI_MAX_NUM_CARDS-1] = -1 };
static u32	mac[  SBNI_MAX_NUM_CARDS ] __initdata;

#ifndef MODULE
typedef u32  iarr[];
static iarr __initdata *dest[5] = { &io, &irq, &baud, &rxl, &mac };
#endif

/* A zero-terminated list of I/O addresses to be probed on ISA bus */
static unsigned int  netcard_portlist[ ] __initdata = { 
	0x210, 0x214, 0x220, 0x224, 0x230, 0x234, 0x240, 0x244, 0x250, 0x254,
	0x260, 0x264, 0x270, 0x274, 0x280, 0x284, 0x290, 0x294, 0x2a0, 0x2a4,
	0x2b0, 0x2b4, 0x2c0, 0x2c4, 0x2d0, 0x2d4, 0x2e0, 0x2e4, 0x2f0, 0x2f4,
	0 };


/*
 * Look for SBNI card which addr stored in dev->base_addr, if nonzero.
 * Otherwise, look through PCI bus. If none PCI-card was found, scan ISA.
 */

static inline int __init
sbni_isa_probe( struct net_device  *dev )
{
	if( dev->base_addr > 0x1ff
	    &&  request_region( dev->base_addr, SBNI_IO_EXTENT, dev->name )
	    &&  sbni_probe1( dev, dev->base_addr, dev->irq ) )

		return  0;
	else {
		printk( KERN_ERR "sbni: base address 0x%lx is busy, or adapter "
			"is malfunctional!\n", dev->base_addr );
		return  -ENODEV;
	}
}

static void __init sbni_devsetup(struct net_device *dev)
{
	ether_setup( dev );
	dev->open		= &sbni_open;
	dev->stop		= &sbni_close;
	dev->hard_start_xmit	= &sbni_start_xmit;
	dev->get_stats		= &sbni_get_stats;
	dev->set_multicast_list	= &set_multicast_list;
	dev->do_ioctl		= &sbni_ioctl;

	SET_MODULE_OWNER( dev );
}

int __init sbni_probe(int unit)
{
	struct net_device *dev;
	static unsigned  version_printed __initdata = 0;
	int err;

	dev = alloc_netdev(sizeof(struct net_local), "sbni", sbni_devsetup);
	if (!dev)
		return -ENOMEM;

	sprintf(dev->name, "sbni%d", unit);
	netdev_boot_setup_check(dev);

	err = sbni_init(dev);
	if (err) {
		free_netdev(dev);
		return err;
	}

	err = register_netdev(dev);
	if (err) {
		release_region( dev->base_addr, SBNI_IO_EXTENT );
		free_netdev(dev);
		return err;
	}
	if( version_printed++ == 0 )
		printk( KERN_INFO "%s", version );
	return 0;
}

static int __init sbni_init(struct net_device *dev)
{
	int  i;
	if( dev->base_addr )
		return  sbni_isa_probe( dev );
	/* otherwise we have to perform search our adapter */

	if( io[ num ] != -1 )
		dev->base_addr	= io[ num ],
		dev->irq	= irq[ num ];
	else if( scandone  ||  io[ 0 ] != -1 )
		return  -ENODEV;

	/* if io[ num ] contains non-zero address, then that is on ISA bus */
	if( dev->base_addr )
		return  sbni_isa_probe( dev );

	/* ...otherwise - scan PCI first */
	if( !skip_pci_probe  &&  !sbni_pci_probe( dev ) )
		return  0;

	if( io[ num ] == -1 ) {
		/* Auto-scan will be stopped when first ISA card were found */
		scandone = 1;
		if( num > 0 )
			return  -ENODEV;
	}

	for( i = 0;  netcard_portlist[ i ];  ++i ) {
		int  ioaddr = netcard_portlist[ i ];
		if( request_region( ioaddr, SBNI_IO_EXTENT, dev->name )
		    &&  sbni_probe1( dev, ioaddr, 0 ))
			return 0;
	}

	return  -ENODEV;
}


int __init
sbni_pci_probe( struct net_device  *dev )
{
	struct pci_dev  *pdev = NULL;

	while( (pdev = pci_get_class( PCI_CLASS_NETWORK_OTHER << 8, pdev ))
	       != NULL ) {
		int  pci_irq_line;
		unsigned long  pci_ioaddr;
		u16  subsys;

		if( pdev->vendor != SBNI_PCI_VENDOR
		    &&  pdev->device != SBNI_PCI_DEVICE )
				continue;

		pci_ioaddr = pci_resource_start( pdev, 0 );
		pci_irq_line = pdev->irq;

		/* Avoid already found cards from previous calls */
		if( !request_region( pci_ioaddr, SBNI_IO_EXTENT, dev->name ) ) {
			pci_read_config_word( pdev, PCI_SUBSYSTEM_ID, &subsys );

			if (subsys != 2)
				continue;

			/* Dual adapter is present */
			if (!request_region(pci_ioaddr += 4, SBNI_IO_EXTENT,
							dev->name ) )
				continue;
		}

		if( pci_irq_line <= 0  ||  pci_irq_line >= NR_IRQS )
			printk( KERN_WARNING "  WARNING: The PCI BIOS assigned "
				"this PCI card to IRQ %d, which is unlikely "
				"to work!.\n"
				KERN_WARNING " You should use the PCI BIOS "
				"setup to assign a valid IRQ line.\n",
				pci_irq_line );

		/* avoiding re-enable dual adapters */
		if( (pci_ioaddr & 7) == 0  &&  pci_enable_device( pdev ) ) {
			release_region( pci_ioaddr, SBNI_IO_EXTENT );
			pci_dev_put( pdev );
			return  -EIO;
		}
		if( sbni_probe1( dev, pci_ioaddr, pci_irq_line ) ) {
			SET_NETDEV_DEV(dev, &pdev->dev);
			/* not the best thing to do, but this is all messed up 
			   for hotplug systems anyway... */
			pci_dev_put( pdev );
			return  0;
		}
	}
	return  -ENODEV;
}


static struct net_device * __init
sbni_probe1( struct net_device  *dev,  unsigned long  ioaddr,  int  irq )
{
	struct net_local  *nl;

	if( sbni_card_probe( ioaddr ) ) {
		release_region( ioaddr, SBNI_IO_EXTENT );
		return NULL;
	}

	outb( 0, ioaddr + CSR0 );

	if( irq < 2 ) {
		unsigned long irq_mask;

		irq_mask = probe_irq_on();
		outb( EN_INT | TR_REQ, ioaddr + CSR0 );
		outb( PR_RES, ioaddr + CSR1 );
		mdelay(50);
		irq = probe_irq_off(irq_mask);
		outb( 0, ioaddr + CSR0 );

		if( !irq ) {
			printk( KERN_ERR "%s: can't detect device irq!\n",
				dev->name );
			release_region( ioaddr, SBNI_IO_EXTENT );
			return NULL;
		}
	} else if( irq == 2 )
		irq = 9;

	dev->irq = irq;
	dev->base_addr = ioaddr;

	/* Allocate dev->priv and fill in sbni-specific dev fields. */
	nl = dev->priv;
	if( !nl ) {
		printk( KERN_ERR "%s: unable to get memory!\n", dev->name );
		release_region( ioaddr, SBNI_IO_EXTENT );
		return NULL;
	}

	dev->priv = nl;
	memset( nl, 0, sizeof(struct net_local) );
	spin_lock_init( &nl->lock );

	/* store MAC address (generate if that isn't known) */
	*(u16 *)dev->dev_addr = htons( 0x00ff );
	*(u32 *)(dev->dev_addr + 2) = htonl( 0x01000000 |
		( (mac[num]  ?  mac[num]  :  (u32)((long)dev->priv)) & 0x00ffffff) );

	/* store link settings (speed, receive level ) */
	nl->maxframe  = DEFAULT_FRAME_LEN;
	nl->csr1.rate = baud[ num ];

	if( (nl->cur_rxl_index = rxl[ num ]) == -1 )
		/* autotune rxl */
		nl->cur_rxl_index = DEF_RXL,
		nl->delta_rxl = DEF_RXL_DELTA;
	else
		nl->delta_rxl = 0;
	nl->csr1.rxl  = rxl_tab[ nl->cur_rxl_index ];
	if( inb( ioaddr + CSR0 ) & 0x01 )
		nl->state |= FL_SLOW_MODE;

	printk( KERN_NOTICE "%s: ioaddr %#lx, irq %d, "
		"MAC: 00:ff:01:%02x:%02x:%02x\n", 
		dev->name, dev->base_addr, dev->irq,
		((u8 *) dev->dev_addr) [3],
		((u8 *) dev->dev_addr) [4],
		((u8 *) dev->dev_addr) [5] );

	printk( KERN_NOTICE "%s: speed %d, receive level ", dev->name,
		( (nl->state & FL_SLOW_MODE)  ?  500000 : 2000000)
		/ (1 << nl->csr1.rate) );

	if( nl->delta_rxl == 0 )
		printk( "0x%x (fixed)\n", nl->cur_rxl_index ); 
	else
		printk( "(auto)\n");

#ifdef CONFIG_SBNI_MULTILINE
	nl->master = dev;
	nl->link   = NULL;
#endif
   
	sbni_cards[ num++ ] = dev;
	return  dev;
}

/* -------------------------------------------------------------------------- */

#ifdef CONFIG_SBNI_MULTILINE

static int
sbni_start_xmit( struct sk_buff  *skb,  struct net_device  *dev )
{
	struct net_device  *p;

	netif_stop_queue( dev );

	/* Looking for idle device in the list */
	for( p = dev;  p; ) {
		struct net_local  *nl = (struct net_local *) p->priv;
		spin_lock( &nl->lock );
		if( nl->tx_buf_p  ||  (nl->state & FL_LINE_DOWN) ) {
			p = nl->link;
			spin_unlock( &nl->lock );
		} else {
			/* Idle dev is found */
			prepare_to_send( skb, p );
			spin_unlock( &nl->lock );
			netif_start_queue( dev );
			return  0;
		}
	}

	return  1;
}

#else	/* CONFIG_SBNI_MULTILINE */

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

	netif_stop_queue( dev );
	spin_lock( &nl->lock );

	prepare_to_send( skb, dev );

	spin_unlock( &nl->lock );
	return  0;
}

#endif	/* CONFIG_SBNI_MULTILINE */

/* -------------------------------------------------------------------------- */

/* interrupt handler */

/*
 * 	SBNI12D-10, -11/ISA boards within "common interrupt" mode could not
 * be looked as two independent single-channel devices. Every channel seems
 * as Ethernet interface but interrupt handler must be common. Really, first
 * channel ("master") driver only registers the handler. In its struct net_local
 * it has got pointer to "slave" channel's struct net_local and handles that's
 * interrupts too.
 *	dev of successfully attached ISA SBNI boards is linked to list.
 * While next board driver is initialized, it scans this list. If one
 * has found dev with same irq and ioaddr different by 4 then it assumes
 * this board to be "master".
 */ 

static irqreturn_t
sbni_interrupt( int  irq,  void  *dev_id,  struct pt_regs  *regs )
{
	struct net_device	  *dev = (struct net_device *) dev_id;
	struct net_local  *nl  = (struct net_local *) dev->priv;
	int	repeat;

	spin_lock( &nl->lock );
	if( nl->second )
		spin_lock( &((struct net_local *) nl->second->priv)->lock );

	do {
		repeat = 0;
		if( inb( dev->base_addr + CSR0 ) & (RC_RDY | TR_RDY) )
			handle_channel( dev ),
			repeat = 1;
		if( nl->second  && 	/* second channel present */
		    (inb( nl->second->base_addr+CSR0 ) & (RC_RDY | TR_RDY)) )
			handle_channel( nl->second ),
			repeat = 1;
	} while( repeat );

	if( nl->second )
		spin_unlock( &((struct net_local *)nl->second->priv)->lock );
	spin_unlock( &nl->lock );
	return IRQ_HANDLED;
}


static void
handle_channel( struct net_device  *dev )
{
	struct net_local	*nl    = (struct net_local *) dev->priv;
	unsigned long		ioaddr = dev->base_addr;

	int  req_ans;
	unsigned char  csr0;

#ifdef CONFIG_SBNI_MULTILINE
	/* Lock the master device because we going to change its local data */
	if( nl->state & FL_SLAVE )
		spin_lock( &((struct net_local *) nl->master->priv)->lock );
#endif

	outb( (inb( ioaddr + CSR0 ) & ~EN_INT) | TR_REQ, ioaddr + CSR0 );

	nl->timer_ticks = CHANGE_LEVEL_START_TICKS;
	for(;;) {
		csr0 = inb( ioaddr + CSR0 );
		if( ( csr0 & (RC_RDY | TR_RDY) ) == 0 )
			break;

		req_ans = !(nl->state & FL_PREV_OK);

		if( csr0 & RC_RDY )
			req_ans = recv_frame( dev );

		/*
		 * TR_RDY always equals 1 here because we have owned the marker,
		 * and we set TR_REQ when disabled interrupts
		 */
		csr0 = inb( ioaddr + CSR0 );
		if( !(csr0 & TR_RDY)  ||  (csr0 & RC_RDY) )
			printk( KERN_ERR "%s: internal error!\n", dev->name );

		/* if state & FL_NEED_RESEND != 0 then tx_frameno != 0 */
		if( req_ans  ||  nl->tx_frameno != 0 )
			send_frame( dev );
		else
			/* send marker without any data */
			outb( inb( ioaddr + CSR0 ) & ~TR_REQ, ioaddr + CSR0 );
	}

	outb( inb( ioaddr + CSR0 ) | EN_INT, ioaddr + CSR0 );

#ifdef CONFIG_SBNI_MULTILINE