ethernet.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

/* $Id: ethernet.c,v 1.34 2002/12/13 07:17:44 starvik Exp $
 *
 * e100net.c: A network driver for the ETRAX 100LX network controller.
 *
 * Copyright (c) 1998-2002 Axis Communications AB.
 *
 * The outline of this driver comes from skeleton.c.
 *
 * $Log: ethernet.c,v $
 * Revision 1.34  2002/12/13 07:17:44  starvik
 * Basic ethtool and MII ioctls
 * Handle out of memory when allocating new buffers
 *
 * Revision 1.33  2002/10/02 20:16:17  hp
 * SETF, SETS: Use underscored IO_x_ macros rather than incorrect token concatenation
 *
 * Revision 1.32  2002/09/16 06:05:58  starvik
 * Align memory returned by dev_alloc_skb
 * Moved handling of sent packets to interrupt to avoid reference counting problem
 *
 * Revision 1.31  2002/09/10 13:28:23  larsv
 * Return -EINVAL for unknown ioctls to avoid confusing tools that tests
 * for supported functionality by issuing special ioctls, i.e. wireless
 * extensions.
 *
 * Revision 1.30  2002/05/07 18:50:08  johana
 * Correct spelling in comments.
 *
 * Revision 1.29  2002/05/06 05:38:49  starvik
 * Performance improvements:
 *    Large packets are not copied (breakpoint set to 256 bytes)
 *    The cache bug workaround is delayed until half of the receive list
 *      has been used
 *    Added transmit list
 *    Transmit interrupts are only enabled when transmit queue is full
 *
 * Revision 1.28.2.1  2002/04/30 08:15:51  starvik
 * Performance improvements:
 *   Large packets are not copied (breakpoint set to 256 bytes)
 *   The cache bug workaround is delayed until half of the receive list
 *     has been used.
 *   Added transmit list
 *   Transmit interrupts are only enabled when transmit queue is full
 *
 * Revision 1.28  2002/04/22 11:47:21  johana
 * Fix according to 2.4.19-pre7. time_after/time_before and
 * missing end of comment.
 * The patch has a typo for ethernet.c in e100_clear_network_leds(),
 *  that is fixed here.
 *
 * Revision 1.27  2002/04/12 11:55:11  bjornw
 * Added TODO
 *
 * Revision 1.26  2002/03/15 17:11:02  bjornw
 * Use prepare_rx_descriptor after the CPU has touched the receiving descs
 *
 * Revision 1.25  2002/03/08 13:07:53  bjornw
 * Unnecessary spinlock removed
 *
 * Revision 1.24  2002/02/20 12:57:43  fredriks
 * Replaced MIN() with min().
 *
 * Revision 1.23  2002/02/20 10:58:14  fredriks
 * Strip the Ethernet checksum (4 bytes) before forwarding a frame to upper layers.
 *
 * Revision 1.22  2002/01/30 07:48:22  matsfg
 * Initiate R_NETWORK_TR_CTRL
 *
 * Revision 1.21  2001/11/23 11:54:49  starvik
 * Added IFF_PROMISC and IFF_ALLMULTI handling in set_multicast_list
 * Removed compiler warnings
 *
 * Revision 1.20  2001/11/12 19:26:00  pkj
 * * Corrected e100_negotiate() to not assign half to current_duplex when
 *   it was supposed to compare them...
 * * Cleaned up failure handling in e100_open().
 * * Fixed compiler warnings.
 *
 * Revision 1.19  2001/11/09 07:43:09  starvik
 * Added full duplex support
 * Added ioctl to set speed and duplex
 * Clear LED timer only runs when LED is lit
 *
 * Revision 1.18  2001/10/03 14:40:43  jonashg
 * Update rx_bytes counter.
 *
 * Revision 1.17  2001/06/11 12:43:46  olof
 * Modified defines for network LED behavior
 *
 * Revision 1.16  2001/05/30 06:12:46  markusl
 * TxDesc.next should not be set to NULL
 *
 * Revision 1.15  2001/05/29 10:27:04  markusl
 * Updated after review remarks:
 * +Use IO_EXTRACT
 * +Handle underrun
 *
 * Revision 1.14  2001/05/29 09:20:14  jonashg
 * Use driver name on printk output so one can tell which driver that complains.
 *
 * Revision 1.13  2001/05/09 12:35:59  johana
 * Use DMA_NBR and IRQ_NBR defines from dma.h and irq.h
 *
 * Revision 1.12  2001/04/05 11:43:11  tobiasa
 * Check dev before panic.
 *
 * Revision 1.11  2001/04/04 11:21:05  markusl
 * Updated according to review remarks
 *
 * Revision 1.10  2001/03/26 16:03:06  bjornw
 * Needs linux/config.h
 *
 * Revision 1.9  2001/03/19 14:47:48  pkj
 * * Make sure there is always a pause after the network LEDs are
 *   changed so they will not look constantly lit during heavy traffic.
 * * Always use HZ when setting times relative to jiffies.
 * * Use LED_NETWORK_SET() when setting the network LEDs.
 *
 * Revision 1.8  2001/02/27 13:52:48  bjornw
 * malloc.h -> slab.h
 *
 * Revision 1.7  2001/02/23 13:46:38  bjornw
 * Spellling check
 *
 * Revision 1.6  2001/01/26 15:21:04  starvik
 * Don't disable interrupts while reading MDIO registers (MDIO is slow)
 * Corrected promiscuous mode
 * Improved deallocation of IRQs ("ifconfig eth0 down" now works)
 *
 * Revision 1.5  2000/11/29 17:22:22  bjornw
 * Get rid of the udword types legacy stuff
 *
 * Revision 1.4  2000/11/22 16:36:09  bjornw
 * Please marketing by using the correct case when spelling Etrax.
 *
 * Revision 1.3  2000/11/21 16:43:04  bjornw
 * Minor short->int change
 *
 * Revision 1.2  2000/11/08 14:27:57  bjornw
 * 2.4 port
 *
 * Revision 1.1  2000/11/06 13:56:00  bjornw
 * Verbatim copy of the 1.24 version of e100net.c from elinux
 *
 * Revision 1.24  2000/10/04 15:55:23  bjornw
 * * Use virt_to_phys etc. for DMA addresses
 * * Removed bogus CHECKSUM_UNNECESSARY
 *
 *
 */

#include <linux/config.h>

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/delay.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/spinlock.h>
#include <linux/errno.h>
#include <linux/init.h>

#include <linux/if.h>
#include <linux/mii.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/ethtool.h>

#include <asm/svinto.h>     /* DMA and register descriptions */
#include <asm/io.h>         /* LED_* I/O functions */
#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/ethernet.h>
#include <asm/cache.h>
#include <asm/uaccess.h>

//#define ETHDEBUG
#define D(x)

/*
 * The name of the card. Is used for messages and in the requests for
 * io regions, irqs and dma channels
 */

static const char* cardname = "ETRAX 100LX built-in ethernet controller";

/* A default ethernet address. Highlevel SW will set the real one later */

static struct sockaddr default_mac = {
	0,
	{ 0x00, 0x40, 0x8C, 0xCD, 0x00, 0x00 }
};

/* Information that need to be kept for each board. */
struct net_local {
	struct net_device_stats stats;

	/* Tx control lock.  This protects the transmit buffer ring
	 * state along with the "tx full" state of the driver.  This
	 * means all netif_queue flow control actions are protected
	 * by this lock as well.
	 */
	spinlock_t lock;
};

typedef struct etrax_eth_descr
{
	etrax_dma_descr descr;
	struct sk_buff* skb;
} etrax_eth_descr;

/* Duplex settings */
enum duplex
{
	half,
	full,
	autoneg
};

/* Dma descriptors etc. */

#define MAX_MEDIA_DATA_SIZE 1518

#define MIN_PACKET_LEN      46
#define ETHER_HEAD_LEN      14

/* 
** MDIO constants.
*/
#define MDIO_BASE_STATUS_REG                0x1
#define MDIO_BASE_CONTROL_REG               0x0
#define MDIO_BC_NEGOTIATE                0x0200
#define MDIO_BC_FULL_DUPLEX_MASK         0x0100
#define MDIO_BC_AUTO_NEG_MASK            0x1000
#define MDIO_BC_SPEED_SELECT_MASK        0x2000
#define MDIO_ADVERTISMENT_REG               0x4
#define MDIO_ADVERT_100_FD                0x100
#define MDIO_ADVERT_100_HD                0x080
#define MDIO_ADVERT_10_FD                 0x040
#define MDIO_ADVERT_10_HD                 0x020
#define MDIO_LINK_UP_MASK                   0x4
#define MDIO_START                          0x1
#define MDIO_READ                           0x2
#define MDIO_WRITE                          0x1
#define MDIO_PREAMBLE              0xfffffffful

/* Broadcom specific */
#define MDIO_AUX_CTRL_STATUS_REG           0x18
#define MDIO_FULL_DUPLEX_IND                0x1
#define MDIO_SPEED                          0x2
#define MDIO_PHYS_ADDR                      0x0

/* Network flash constants */
#define NET_FLASH_TIME                  (HZ/50) /* 20 ms */
#define NET_FLASH_PAUSE                (HZ/100) /* 10 ms */
#define NET_LINK_UP_CHECK_INTERVAL       (2*HZ) /* 2 s   */
#define NET_DUPLEX_CHECK_INTERVAL        (2*HZ) /* 2 s   */

#define NO_NETWORK_ACTIVITY 0
#define NETWORK_ACTIVITY    1

#define NBR_OF_RX_DESC     64
#define NBR_OF_TX_DESC     256

/* Large packets are sent directly to upper layers while small packets are */
/* copied (to reduce memory waste). The following constant decides the breakpoint */
#define RX_COPYBREAK 256

/* Due to a chip bug we need to flush the cache when descriptors are returned */
/* to the DMA. To decrease performance impact we return descriptors in chunks. */
/* The following constant determines the number of descriptors to return. */
#define RX_QUEUE_THRESHOLD  NBR_OF_RX_DESC/2

#define GET_BIT(bit,val)   (((val) >> (bit)) & 0x01)

/* Define some macros to access ETRAX 100 registers */
#define SETF(var, reg, field, val) var = (var & ~IO_MASK_(reg##_, field##_)) | \
					  IO_FIELD_(reg##_, field##_, val)
#define SETS(var, reg, field, val) var = (var & ~IO_MASK_(reg##_, field##_)) | \
					  IO_STATE_(reg##_, field##_, _##val)

static etrax_eth_descr *myNextRxDesc;  /* Points to the next descriptor to
                                          to be processed */
static etrax_eth_descr *myLastRxDesc;  /* The last processed descriptor */
static etrax_eth_descr *myPrevRxDesc;  /* The descriptor right before myNextRxDesc */

static etrax_eth_descr RxDescList[NBR_OF_RX_DESC] __attribute__ ((aligned(32)));

static etrax_eth_descr* myFirstTxDesc; /* First packet not yet sent */
static etrax_eth_descr* myLastTxDesc;  /* End of send queue */
static etrax_eth_descr* myNextTxDesc;  /* Next descriptor to use */
static etrax_eth_descr TxDescList[NBR_OF_TX_DESC] __attribute__ ((aligned(32)));

static unsigned int network_rec_config_shadow = 0;

/* Network speed indication. */
static struct timer_list speed_timer;
static struct timer_list clear_led_timer;
static int current_speed; /* Speed read from tranceiver */
static int current_speed_selection; /* Speed selected by user */
static int led_next_time;
static int led_active;
static int rx_queue_len;

/* Duplex */
static struct timer_list duplex_timer;
static int full_duplex;
static enum duplex current_duplex;

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

static int etrax_ethernet_init(struct net_device *dev);

static int e100_open(struct net_device *dev);
static int e100_set_mac_address(struct net_device *dev, void *addr);
static int e100_send_packet(struct sk_buff *skb, struct net_device *dev);
static void e100rxtx_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static void e100nw_interrupt(int irq, void *dev_id, struct pt_regs *regs);
static void e100_rx(struct net_device *dev);
static int e100_close(struct net_device *dev);
static int e100_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
static int e100_ethtool_ioctl(struct net_device* dev, struct ifreq *ifr);
static void e100_tx_timeout(struct net_device *dev);
static struct net_device_stats *e100_get_stats(struct net_device *dev);
static void set_multicast_list(struct net_device *dev);
static void e100_hardware_send_packet(char *buf, int length);
static void update_rx_stats(struct net_device_stats *);
static void update_tx_stats(struct net_device_stats *);

static void e100_check_speed(unsigned long dummy);
static void e100_set_speed(unsigned long speed);
static void e100_check_duplex(unsigned long dummy);
static void e100_set_duplex(enum duplex);
static void e100_negotiate(void);

static unsigned short e100_get_mdio_reg(unsigned char reg_num);
static void e100_set_mdio_reg(unsigned char reg, unsigned short data);
static void e100_send_mdio_cmd(unsigned short cmd, int write_cmd);
static void e100_send_mdio_bit(unsigned char bit);
static unsigned char e100_receive_mdio_bit(void);
static void e100_reset_tranceiver(void);

static void e100_clear_network_leds(unsigned long dummy);
static void e100_set_network_leds(int active);

#define tx_done(dev) (*R_DMA_CH0_CMD == 0)

/*
 * Check for a network adaptor of this type, and return '0' if 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).
 */

static int __init
etrax_ethernet_init(struct net_device *dev)
{
	int i;

	printk("ETRAX 100LX 10/100MBit ethernet v2.0 (c) 2000-2001 Axis Communications AB\n");

	dev->base_addr = (unsigned int)R_NETWORK_SA_0; /* just to have something to show */

	printk("%s initialized\n", dev->name);

	/* make Linux aware of the new hardware  */

	if (!dev) {
		printk(KERN_WARNING "%s: dev == NULL. Should this happen?\n",
		       cardname);
		dev = init_etherdev(dev, sizeof(struct net_local));
		if (!dev)
			panic("init_etherdev failed\n");
	}

	/* setup generic handlers and stuff in the dev struct */

	ether_setup(dev);

	/* make room for the local structure containing stats etc */

	dev->priv = kmalloc(sizeof(struct net_local), GFP_KERNEL);
	if (dev->priv == NULL)
		return -ENOMEM;
	memset(dev->priv, 0, sizeof(struct net_local));

	/* now setup our etrax specific stuff */

	dev->irq = NETWORK_DMA_RX_IRQ_NBR; /* we really use DMATX as well... */
	dev->dma = NETWORK_RX_DMA_NBR;

	/* fill in our handlers so the network layer can talk to us in the future */

	dev->open               = e100_open;
	dev->hard_start_xmit    = e100_send_packet;
	dev->stop               = e100_close;
	dev->get_stats          = e100_get_stats;
	dev->set_multicast_list = set_multicast_list;
	dev->set_mac_address    = e100_set_mac_address;
	dev->do_ioctl           = e100_ioctl;
	dev->tx_timeout         = e100_tx_timeout;

	/* set the default MAC address */

	e100_set_mac_address(dev, &default_mac);

	/* Initialise the list of Etrax DMA-descriptors */

	/* Initialise receive descriptors */

	for (i = 0; i < NBR_OF_RX_DESC; i++) {
		/* Allocate two extra cachelines to make sure that buffer used by DMA
		 * does not share cacheline with any other data (to avoid cache bug)
		 */
		RxDescList[i].skb = dev_alloc_skb(MAX_MEDIA_DATA_SIZE + 2 * L1_CACHE_BYTES);
		RxDescList[i].descr.ctrl   = 0;
		RxDescList[i].descr.sw_len = MAX_MEDIA_DATA_SIZE;
		RxDescList[i].descr.next   = virt_to_phys(&RxDescList[i + 1]);
		RxDescList[i].descr.buf    = L1_CACHE_ALIGN(virt_to_phys(RxDescList[i].skb->data));
		RxDescList[i].descr.status = 0;
		RxDescList[i].descr.hw_len = 0;
             
		prepare_rx_descriptor(&RxDescList[i].descr);
	}

	RxDescList[NBR_OF_RX_DESC - 1].descr.ctrl   = d_eol;
	RxDescList[NBR_OF_RX_DESC - 1].descr.next   = virt_to_phys(&RxDescList[0]);
	rx_queue_len = 0;

	/* Initialize transmit descriptors */
	for (i = 0; i < NBR_OF_TX_DESC; i++) {
		TxDescList[i].descr.ctrl   = 0;
		TxDescList[i].descr.sw_len = 0;
		TxDescList[i].descr.next   = virt_to_phys(&TxDescList[i + 1].descr);
		TxDescList[i].descr.buf    = 0;
		TxDescList[i].descr.status = 0;
		TxDescList[i].descr.hw_len = 0;
		TxDescList[i].skb = 0;
	}

	TxDescList[NBR_OF_TX_DESC - 1].descr.ctrl   = d_eol;
	TxDescList[NBR_OF_TX_DESC - 1].descr.next   = virt_to_phys(&TxDescList[0].descr);
        
	/* Initialise initial pointers */

	myNextRxDesc  = &RxDescList[0];
	myLastRxDesc  = &RxDescList[NBR_OF_RX_DESC - 1];
	myPrevRxDesc  = &RxDescList[NBR_OF_RX_DESC - 1];
	myFirstTxDesc = &TxDescList[0];
	myNextTxDesc  = &TxDescList[0];
	myLastTxDesc  = &TxDescList[NBR_OF_TX_DESC - 1];

	/* Initialize speed indicator stuff. */

	current_speed = 10;
	current_speed_selection = 0; /* Auto */
	speed_timer.expires = jiffies + NET_LINK_UP_CHECK_INTERVAL;
	speed_timer.function = e100_check_speed;
	add_timer(&speed_timer);
        
	clear_led_timer.function = e100_clear_network_leds;
        
	full_duplex = 0;
	current_duplex = autoneg;
	duplex_timer.expires = jiffies + NET_DUPLEX_CHECK_INTERVAL;		
	duplex_timer.function = e100_check_duplex;
	add_timer(&duplex_timer);

	return 0;
}

/* set MAC address of the interface. called from the core after a
 * SIOCSIFADDR ioctl, and from the bootup above.
 */

static int
e100_set_mac_address(struct net_device *dev, void *p)
{
	struct sockaddr *addr = p;
	int i;

	/* remember it */

	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);

	/* Write it to the hardware.
	 * Note the way the address is wrapped:
	 * *R_NETWORK_SA_0 = a0_0 | (a0_1 << 8) | (a0_2 << 16) | (a0_3 << 24);
	 * *R_NETWORK_SA_1 = a0_4 | (a0_5 << 8);
	 */
	
	*R_NETWORK_SA_0 = dev->dev_addr[0] | (dev->dev_addr[1] << 8) |
		(dev->dev_addr[2] << 16) | (dev->dev_addr[3] << 24);
	*R_NETWORK_SA_1 = dev->dev_addr[4] | (dev->dev_addr[5] << 8);
	*R_NETWORK_SA_2 = 0;

	/* show it in the log as well */

	printk("%s: changed MAC to ", dev->name);

	for (i = 0; i < 5; i++)
		printk("%02X:", dev->dev_addr[i]);

	printk("%02X\n", dev->dev_addr[i]);

	return 0;
}