sdla_fr.c

讲述linux的初始化过程

/*****************************************************************************
* sdla_fr.c	WANPIPE(tm) Multiprotocol WAN Link Driver. Frame relay module.
*
* Author(s):	Nenad Corbic  <[e-mail]>
*		Gideon Hack
*
* Copyright:	(c) 1995-1999 Sangoma Technologies Inc.
*
*		This program is free software; you can redistribute it and/or
*		modify it under the terms of the GNU General Public License
*		as published by the Free Software Foundation; either version
*		2 of the License, or (at your option) any later version.
* ============================================================================
* Feb 28, 2000  Jeff Garzik	o softnet updates
* Nov 08, 1999  Nenad Corbic    o Combined all debug UDP calls into one function
*                               o Removed the ARP support. This has to be done
*                                 in the next version.
*                               o Only a Node can implement NO signalling.
*                                 Initialize DLCI during if_open() if NO 
*				  signalling.
*				o Took out IPX support, implement in next
*                                 version
* Sep 29, 1999  Nenad Corbic	o Added SMP support and changed the update
*                                 function to use timer interrupt.
*				o Fixed the CIR bug:  Set the value of BC
*                                 to CIR when the CIR is enabled.
*  				o Updated comments, statistics and tracing.
* Jun 02, 1999	Gideon Hack	o Updated for S514 support.
* Sep 18, 1998	Jaspreet Singh	o Updated for 2.2.X kernels.
* Jul 31, 1998	Jaspreet Singh	o Removed wpf_poll routine.  The channel/DLCI 
*				  status is received through an event interrupt.
* Jul 08, 1998	David Fong	o Added inverse ARP support.
* Mar 26, 1997	Jaspreet Singh	o Returning return codes for failed UDP cmds.
* Jan 28, 1997	Jaspreet Singh  o Improved handling of inactive DLCIs.
* Dec 30, 1997	Jaspreet Singh	o Replaced dev_tint() with mark_bh(NET_BH)
* Dec 16, 1997	Jaspreet Singh	o Implemented Multiple IPX support.
* Nov 26, 1997	Jaspreet Singh	o Improved load sharing with multiple boards
*				o Added Cli() to protect enabling of interrupts
*				  while polling is called.
* Nov 24, 1997	Jaspreet Singh	o Added counters to avoid enabling of interrupts
*				  when they have been disabled by another
*				  interface or routine (eg. wpf_poll).
* Nov 06, 1997	Jaspreet Singh	o Added INTR_TEST_MODE to avoid polling	
*				  routine disable interrupts during interrupt
*				  testing.
* Oct 20, 1997  Jaspreet Singh  o Added hooks in for Router UP time.
* Oct 16, 1997  Jaspreet Singh  o The critical flag is used to maintain flow
*                                 control by avoiding RACE conditions.  The
*                                 cli() and restore_flags() are taken out.
*                                 The fr_channel structure is appended for 
*                                 Driver Statistics.
* Oct 15, 1997  Farhan Thawar    o updated if_send() and receive for IPX
* Aug 29, 1997  Farhan Thawar    o Removed most of the cli() and sti()
*                                o Abstracted the UDP management stuff
*                                o Now use tbusy and critical more intelligently
* Jul 21, 1997  Jaspreet Singh	 o Can configure T391, T392, N391, N392 & N393
*				   through router.conf.
*				 o Protected calls to sdla_peek() by adDing 
*				   save_flags(), cli() and restore_flags().
*				 o Added error message for Inactive DLCIs in
*				   fr_event() and update_chan_state().
*				 o Fixed freeing up of buffers using kfree() 
*			           when packets are received.
* Jul 07, 1997	Jaspreet Singh	 o Added configurable TTL for UDP packets 
*				 o Added ability to discard multicast and 
*				   broadcast source addressed packets
* Jun 27, 1997	Jaspreet Singh	 o Added FT1 monitor capabilities 
*				   New case (0x44) statement in if_send routine 
*				   Added a global variable rCount to keep track
*			 	   of FT1 status enabled on the board.
* May 29, 1997	Jaspreet Singh	 o Fixed major Flow Control Problem
*				   With multiple boards a problem was seen where
*				   the second board always stopped transmitting
*				   packet after running for a while. The code
*				   got into a stage where the interrupts were
*				   disabled and dev->tbusy was set to 1.
*                  		   This caused the If_send() routine to get into
*                                  the if clause for it(0,dev->tbusy) 
*				   forever.
*				   The code got into this stage due to an 
*				   interrupt occuring within the if clause for 
*				   set_bit(0,dev->tbusy).  Since an interrupt 
*				   disables furhter transmit interrupt and 
* 				   makes dev->tbusy = 0, this effect was undone 
*                                  by making dev->tbusy = 1 in the if clause.
*				   The Fix checks to see if Transmit interrupts
*				   are disabled then do not make dev->tbusy = 1
* 	   			   Introduced a global variable: int_occur and
*				   added tx_int_enabled in the wan_device 
*				   structure.	
* May 21, 1997  Jaspreet Singh   o Fixed UDP Management for multiple
*                                  boards.
*
* Apr 25, 1997  Farhan Thawar    o added UDP Management stuff
*                                o fixed bug in if_send() and tx_intr() to
*                                  sleep and wakeup all devices
* Mar 11, 1997  Farhan Thawar   Version 3.1.1
*                                o fixed (+1) bug in fr508_rx_intr()
*                                o changed if_send() to return 0 if
*                                  wandev.critical() is true
*                                o free socket buffer in if_send() if
*                                  returning 0 
*                                o added tx_intr() routine
* Jan 30, 1997	Gene Kozin	Version 3.1.0
*				 o implemented exec() entry point
*				 o fixed a bug causing driver configured as
*				   a FR switch to be stuck in WAN_
*				   mode
* Jan 02, 1997	Gene Kozin	Initial version.
*****************************************************************************/

#include <linux/config.h>
#include <linux/kernel.h>	/* printk(), and other useful stuff */
#include <linux/stddef.h>	/* offsetof(), etc. */
#include <linux/errno.h>	/* return codes */
#include <linux/string.h>	/* inline memset(), etc. */
#include <linux/malloc.h>	/* kmalloc(), kfree() */
#include <linux/wanrouter.h>	/* WAN router definitions */
#include <linux/wanpipe.h>	/* WANPIPE common user API definitions */
#include <linux/if_arp.h>	/* ARPHRD_* defines */
#include <asm/byteorder.h>	/* htons(), etc. */
#include <asm/io.h>		/* for inb(), outb(), etc. */
#include <linux/time.h>	 	/* for do_gettimeofday */	
#include <linux/in.h>		/* sockaddr_in */
#include <linux/inet.h>		/* in_ntoa(), etc... */
#include <asm/uaccess.h>
#include <linux/inetdevice.h>
#include <linux/ip.h>
#include <net/route.h>          /* Dynamic Route Creation */
#include <linux/if.h>

#include <linux/sdla_fr.h>	/* frame relay firmware API definitions */
 
/****** Defines & Macros ****************************************************/

#define	MAX_CMD_RETRY	10		/* max number of firmware retries */

#define	FR_HEADER_LEN	8		/* max encapsulation header size */
#define	FR_CHANNEL_MTU	1500		/* unfragmented logical channel MTU */

/* Q.922 frame types */
#define	Q922_UI		0x03		/* Unnumbered Info frame */
#define	Q922_XID	0xAF		

/* DLCI configured or not */
#define DLCI_NOT_CONFIGURED	0x00
#define DLCI_CONFIG_PENDING	0x01
#define DLCI_CONFIGURED		0x02

/* CIR enabled or not */
#define CIR_ENABLED	0x00
#define CIR_DISABLED	0x01

#define WANPIPE 0x00
#define API     0x01
#define FRAME_RELAY_API 1

#define TX_TIMEOUT	(5*HZ)

/* For handle_IPXWAN() */
#define CVHexToAscii(b) (((unsigned char)(b) > (unsigned char)9) ? ((unsigned char)'A' + ((unsigned char)(b) - (unsigned char)10)) : ((unsigned char)'0' + (unsigned char)(b)))
 
/****** Data Structures *****************************************************/

/* This is an extention of the 'struct net_device' we create for each network
 * interface to keep the rest of channel-specific data.
 */
typedef struct fr_channel
{
	/* This member must be first. */
	struct net_device *slave;	/* WAN slave */

	char name[WAN_IFNAME_SZ+1];	/* interface name, ASCIIZ */
	unsigned dlci_configured  ;	/* check whether configured or not */
	unsigned cir_status;		/* check whether CIR enabled or not */
	unsigned dlci;			/* logical channel number */
	unsigned cir;			/* committed information rate */
	unsigned bc;			/* committed burst size */
	unsigned be;			/* excess burst size */
	unsigned mc;			/* multicast support on or off */
	unsigned tx_int_status;		/* Transmit Interrupt Status */	
	unsigned short pkt_length;	/* Packet Length */
	unsigned long router_start_time;/* Router start time in seconds */
	unsigned long tick_counter;	/* counter for transmit time out */
	char dev_pending_devtint;	/* interface pending dev_tint() */
	char state;			/* channel state */
	void *dlci_int_interface;	/* pointer to the DLCI Interface */ 
	unsigned long IB_addr;		/* physical address of Interface Byte */
	unsigned long state_tick;	/* time of the last state change */
	unsigned char enable_IPX;	/* Enable/Disable the use of IPX */
	unsigned long network_number;	/* Internal Network Number for IPX*/
	sdla_t *card;			/* -> owner */
	unsigned route_flag;		/* Add/Rem dest addr in route tables */
	unsigned inarp;			/* Inverse Arp Request status */ 
	int inarp_interval;		/* Time between InArp Requests */
	unsigned long inarp_tick;	/* InArp jiffies tick counter */
	struct net_device_stats ifstats;	/* interface statistics */
	if_send_stat_t drvstats_if_send;
        rx_intr_stat_t drvstats_rx_intr;
        pipe_mgmt_stat_t drvstats_gen;

	unsigned char usedby;  /* Used by WANPIPE or API */

	unsigned long router_up_time;

	unsigned short transmit_length;
	char transmit_buffer[FR_MAX_NO_DATA_BYTES_IN_FRAME];
} fr_channel_t;

/* Route Flag options */
#define NO_ROUTE	0x00
#define ADD_ROUTE 	0x01
#define ROUTE_ADDED	0x02
#define REMOVE_ROUTE 	0x03

/* inarp options */
#define INARP_NONE		0x00
#define INARP_REQUEST		0x01
#define INARP_CONFIGURED	0x02

/* reasons for enabling the timer interrupt on the adapter */
#define TMR_INT_ENABLED_UDP   	0x01
#define TMR_INT_ENABLED_UPDATE 	0x02


typedef struct dlci_status
{
	unsigned short dlci	PACKED;
	unsigned char state	PACKED;
} dlci_status_t;

typedef struct dlci_IB_mapping
{
	unsigned short dlci		PACKED;
	unsigned long  addr_value	PACKED;
} dlci_IB_mapping_t;

/* This structure is used for DLCI list Tx interrupt mode.  It is used to
   enable interrupt bit and set the packet length for transmission
 */
typedef struct fr_dlci_interface 
{
	unsigned char gen_interrupt	PACKED;
	unsigned short packet_length	PACKED;
	unsigned char reserved		PACKED;
} fr_dlci_interface_t; 

/* variable for keeping track of enabling/disabling FT1 monitor status */
static int rCount = 0;

extern int ip_rt_ioctl(unsigned int, void *);
extern void disable_irq(unsigned int);
extern void enable_irq(unsigned int);

/* variable for keeping track of number of interrupts generated during 
 * interrupt test routine 
 */
static int Intr_test_counter;
/****** Function Prototypes *************************************************/

/* WAN link driver entry points. These are called by the WAN router module. */
static int update(wan_device_t *wandev);
static int new_if(wan_device_t *wandev, struct net_device *dev, wanif_conf_t *conf);
static int del_if(wan_device_t *wandev, struct net_device *dev);

/* WANPIPE-specific entry points */
static int wpf_exec(struct sdla *card, void *u_cmd, void *u_data);

/* Network device interface */
static int if_init(struct net_device *dev);
static int if_open(struct net_device *dev);
static int if_close(struct net_device *dev);
static int if_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, void *daddr, void *saddr, unsigned len);
static int if_rebuild_hdr(struct sk_buff *skb);
static int if_send(struct sk_buff *skb, struct net_device *dev);
static void if_tx_timeout (struct net_device *dev);
static int chk_bcast_mcast_addr(sdla_t *card, struct net_device* dev,
                                struct sk_buff *skb);
static struct net_device_stats *if_stats(struct net_device *dev);

/* Interrupt handlers */
static void fr_isr(sdla_t *card);
static void rx_intr(sdla_t *card);
static void tx_intr(sdla_t *card);
static void timer_intr(sdla_t *card);
static void spur_intr(sdla_t *card);

/* Frame relay firmware interface functions */
static int fr_read_version(sdla_t *card, char *str);
static int fr_configure(sdla_t *card, fr_conf_t *conf);
static int fr_dlci_configure(sdla_t *card, fr_dlc_conf_t *conf, unsigned dlci);
static int fr_init_dlci (sdla_t *card, fr_channel_t *chan);
static int fr_set_intr_mode (sdla_t *card, unsigned mode, unsigned mtu, unsigned short timeout);
static int fr_comm_enable(sdla_t *card);
static int fr_comm_disable(sdla_t *card);
static int fr_get_err_stats(sdla_t *card);
static int fr_get_stats(sdla_t *card);
static int fr_add_dlci(sdla_t *card, int dlci);
static int fr_activate_dlci(sdla_t *card, int dlci);
static int fr_delete_dlci (sdla_t* card, int dlci);
static int fr_issue_isf(sdla_t *card, int isf);
static int fr_send(sdla_t *card, int dlci, unsigned char attr, int len,
	void *buf);

/* Firmware asynchronous event handlers */
static int fr_event(sdla_t *card, int event, fr_mbox_t *mbox);
static int fr_modem_failure(sdla_t *card, fr_mbox_t *mbox);
static int fr_dlci_change(sdla_t *card, fr_mbox_t *mbox);

/* Miscellaneous functions */
static int update_chan_state(struct net_device *dev);
static void set_chan_state(struct net_device *dev, int state);
static struct net_device *find_channel(sdla_t *card, unsigned dlci);
static int is_tx_ready(sdla_t *card, fr_channel_t *chan);
static unsigned int dec_to_uint(unsigned char *str, int len);
static int reply_udp( unsigned char *data, unsigned int mbox_len );

static int intr_test( sdla_t* card );
static void init_chan_statistics( fr_channel_t* chan );
static void init_global_statistics( sdla_t* card );
static void read_DLCI_IB_mapping( sdla_t* card, fr_channel_t* chan );
static void setup_for_delayed_transmit(struct net_device* dev, void* buf,
	unsigned len);


/* Inverse ARP and Dynamic routing functions */
int process_ARP(arphdr_1490_t *ArpPacket, sdla_t *card, struct net_device *dev);
int is_arp(void *buf);
int send_inarp_request(sdla_t *card, struct net_device *dev);

/* Udp management functions */
static int process_udp_mgmt_pkt(sdla_t *card);
static int udp_pkt_type( struct sk_buff *skb, sdla_t *card );
static int store_udp_mgmt_pkt(int udp_type, char udp_pkt_src, sdla_t* card,
                                struct sk_buff *skb, int dlci);

/* IPX functions */
static void switch_net_numbers(unsigned char *sendpacket,
	unsigned long network_number, unsigned char incoming);

static int handle_IPXWAN(unsigned char *sendpacket, char *devname,
	unsigned char enable_IPX, unsigned long network_number);

/* Lock Functions: SMP supported */
void 	s508_s514_unlock(sdla_t *card, unsigned long *smp_flags);
void 	s508_s514_lock(sdla_t *card, unsigned long *smp_flags);

unsigned short calc_checksum (char *, int);


/****** Public Functions ****************************************************/

/*============================================================================
 * Frame relay protocol initialization routine.
 *
 * This routine is called by the main WANPIPE module during setup.  At this
 * point adapter is completely initialized and firmware is running.
 *  o read firmware version (to make sure it's alive)
 *  o configure adapter
 *  o initialize protocol-specific fields of the adapter data space.
 *
 * Return:	0	o.k.
 *		< 0	failure.
 */
int wpf_init(sdla_t *card, wandev_conf_t *conf)
{

	int err;

	union
	{
		char str[80];
		fr_conf_t cfg;
	} u;
	fr_buf_info_t* buf_info;
	int i;

	/* Verify configuration ID */
	if (conf->config_id != WANCONFIG_FR) {
		
		printk(KERN_INFO "%s: invalid configuration ID %u!\n",
			card->devname, conf->config_id);
		return -EINVAL;
	
	}

	/* Initialize protocol-specific fields of adapter data space */
	switch (card->hw.fwid) {
	
		case SFID_FR508:
			card->mbox  = (void*)(card->hw.dpmbase + 
					FR508_MBOX_OFFS);
			card->flags = (void*)(card->hw.dpmbase + 
					FR508_FLAG_OFFS);
			if(card->hw.type == SDLA_S514) {
				card->mbox += FR_MB_VECTOR;
                                card->flags += FR_MB_VECTOR;
			}
                        card->isr = &fr_isr;
			break;

		default:
			return -EINVAL;
	}

	/* Read firmware version.  Note that when adapter initializes, it
	 * clears the mailbox, so it may appear that the first command was
	 * executed successfully when in fact it was merely erased. To work
	 * around this, we execute the first command twice.
	 */

	if (fr_read_version(card, NULL) || fr_read_version(card, u.str))
		return -EIO;

	printk(KERN_INFO "%s: running frame relay firmware v%s\n",
		card->devname, u.str);

	/* Adjust configuration */
	conf->mtu += FR_HEADER_LEN;
	conf->mtu = (conf->mtu >= MIN_LGTH_FR_DATA_CFG) ?
			min(conf->mtu, FR_MAX_NO_DATA_BYTES_IN_FRAME) :
                        FR_CHANNEL_MTU + FR_HEADER_LEN;
     
	conf->bps = min(conf->bps, 2048000);

	/* Initialze the configuration structure sent to the board to zero */
	memset(&u.cfg, 0, sizeof(u.cfg));

	memset(card->u.f.dlci_to_dev_map, 0, sizeof(card->u.f.dlci_to_dev_map));
 	
	/* Configure adapter firmware */
	
	u.cfg.mtu	= conf->mtu;