net/eth.c - github/trini/u-boot - Gitiles

 /*
  * (C) Copyright 2001-2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

 #include <common.h>
 #include <command.h>
 #include <net.h>
 #include <miiphy.h>
 #include <phy.h>
 #include <asm/errno.h>

 void eth_parse_enetaddr(const char *addr, uchar *enetaddr)
 {
 	char *end;
 	int i;

 	for (i = 0; i < 6; ++i) {
 		enetaddr[i] = addr ? simple_strtoul(addr, &end, 16) : 0;
 		if (addr)
 			addr = (*end) ? end + 1 : end;
 	}
 }

 int eth_getenv_enetaddr(char *name, uchar *enetaddr)
 {
 	eth_parse_enetaddr(getenv(name), enetaddr);
 	return is_valid_ether_addr(enetaddr);
 }

 int eth_setenv_enetaddr(char *name, const uchar *enetaddr)
 {
 	char buf[20];

 	sprintf(buf, "%pM", enetaddr);

 	return setenv(name, buf);
 }

 int eth_getenv_enetaddr_by_index(const char *base_name, int index,
 				 uchar *enetaddr)
 {
 	char enetvar[32];
 	sprintf(enetvar, index ? "%s%daddr" : "%saddr", base_name, index);
 	return eth_getenv_enetaddr(enetvar, enetaddr);
 }

 static inline int eth_setenv_enetaddr_by_index(const char *base_name, int index,
 				 uchar *enetaddr)
 {
 	char enetvar[32];
 	sprintf(enetvar, index ? "%s%daddr" : "%saddr", base_name, index);
 	return eth_setenv_enetaddr(enetvar, enetaddr);
 }


 static int eth_mac_skip(int index)
 {
 	char enetvar[15];
 	char *skip_state;
 	sprintf(enetvar, index ? "eth%dmacskip" : "ethmacskip", index);
 	return ((skip_state = getenv(enetvar)) != NULL);
 }

 /*
  * CPU and board-specific Ethernet initializations.  Aliased function
  * signals caller to move on
  */
 static int __def_eth_init(bd_t *bis)
 {
 	return -1;
 }
 int cpu_eth_init(bd_t *bis) __attribute__((weak, alias("__def_eth_init")));
 int board_eth_init(bd_t *bis) __attribute__((weak, alias("__def_eth_init")));

 #ifdef CONFIG_API
 static struct {
 	uchar data[PKTSIZE];
 	int length;
 } eth_rcv_bufs[PKTBUFSRX];

 static unsigned int eth_rcv_current, eth_rcv_last;
 #endif

 static struct eth_device *eth_devices;
 struct eth_device *eth_current;

 struct eth_device *eth_get_dev_by_name(const char *devname)
 {
 	struct eth_device *dev, *target_dev;

 	BUG_ON(devname == NULL);

 	if (!eth_devices)
 		return NULL;

 	dev = eth_devices;
 	target_dev = NULL;
 	do {
 		if (strcmp(devname, dev->name) == 0) {
 			target_dev = dev;
 			break;
 		}
 		dev = dev->next;
 	} while (dev != eth_devices);

 	return target_dev;
 }

 struct eth_device *eth_get_dev_by_index(int index)
 {
 	struct eth_device *dev, *target_dev;

 	if (!eth_devices)
 		return NULL;

 	dev = eth_devices;
 	target_dev = NULL;
 	do {
 		if (dev->index == index) {
 			target_dev = dev;
 			break;
 		}
 		dev = dev->next;
 	} while (dev != eth_devices);

 	return target_dev;
 }

 int eth_get_dev_index(void)
 {
 	if (!eth_current)
 		return -1;

 	return eth_current->index;
 }

 static void eth_current_changed(void)
 {
 	char *act = getenv("ethact");
 	/* update current ethernet name */
 	if (eth_current) {
 		if (act == NULL || strcmp(act, eth_current->name) != 0)
 			setenv("ethact", eth_current->name);
 	}
 	/*
 	 * remove the variable completely if there is no active
 	 * interface
 	 */
 	else if (act != NULL)
 		setenv("ethact", NULL);
 }

 int eth_address_set(unsigned char *addr)
 {
 	return memcmp(addr, "\0\0\0\0\0\0", 6);
 }

 int eth_write_hwaddr(struct eth_device *dev, const char *base_name,
 		   int eth_number)
 {
 	unsigned char env_enetaddr[6];
 	int ret = 0;

 	eth_getenv_enetaddr_by_index(base_name, eth_number, env_enetaddr);

 	if (eth_address_set(env_enetaddr)) {
 		if (eth_address_set(dev->enetaddr) &&
 				memcmp(dev->enetaddr, env_enetaddr, 6)) {
 			printf("\nWarning: %s MAC addresses don't match:\n",
 				dev->name);
 			printf("Address in SROM is         %pM\n",
 				dev->enetaddr);
 			printf("Address in environment is  %pM\n",
 				env_enetaddr);
 		}

 		memcpy(dev->enetaddr, env_enetaddr, 6);
 	} else if (is_valid_ether_addr(dev->enetaddr)) {
 		eth_setenv_enetaddr_by_index(base_name, eth_number,
 					     dev->enetaddr);
 		printf("\nWarning: %s using MAC address from net device\n",
 			dev->name);
 	} else if (!(eth_address_set(dev->enetaddr))) {
 		printf("\nError: %s address not set.\n",
 		       dev->name);
 		return -EINVAL;
 	}

 	if (dev->write_hwaddr && !eth_mac_skip(eth_number)) {
 		if (!is_valid_ether_addr(dev->enetaddr)) {
 			printf("\nError: %s address %pM illegal value\n",
 				 dev->name, dev->enetaddr);
 			return -EINVAL;
 		}

 		ret = dev->write_hwaddr(dev);
 		if (ret)
 			printf("\nWarning: %s failed to set MAC address\n", dev->name);
 	}

 	return ret;
 }

 int eth_register(struct eth_device *dev)
 {
 	struct eth_device *d;
 	static int index;

 	assert(strlen(dev->name) < sizeof(dev->name));

 	if (!eth_devices) {
 		eth_current = eth_devices = dev;
 		eth_current_changed();
 	} else {
 		for (d = eth_devices; d->next != eth_devices; d = d->next)
 			;
 		d->next = dev;
 	}

 	dev->state = ETH_STATE_INIT;
 	dev->next  = eth_devices;
 	dev->index = index++;

 	return 0;
 }

 int eth_unregister(struct eth_device *dev)
 {
 	struct eth_device *cur;

 	/* No device */
 	if (!eth_devices)
 		return -1;

 	for (cur = eth_devices; cur->next != eth_devices && cur->next != dev;
 	     cur = cur->next)
 		;

 	/* Device not found */
 	if (cur->next != dev)
 		return -1;

 	cur->next = dev->next;

 	if (eth_devices == dev)
 		eth_devices = dev->next == eth_devices ? NULL : dev->next;

 	if (eth_current == dev) {
 		eth_current = eth_devices;
 		eth_current_changed();
 	}

 	return 0;
 }

 static void eth_env_init(bd_t *bis)
 {
 	const char *s;

 	if ((s = getenv("bootfile")) != NULL)
 		copy_filename(BootFile, s, sizeof(BootFile));
 }

 int eth_initialize(bd_t *bis)
 {
 	int num_devices = 0;
 	eth_devices = NULL;
 	eth_current = NULL;

 	bootstage_mark(BOOTSTAGE_ID_NET_ETH_START);
 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII) || defined(CONFIG_PHYLIB)
 	miiphy_init();
 #endif

 #ifdef CONFIG_PHYLIB
 	phy_init();
 #endif

 	eth_env_init(bis);

 	/*
 	 * If board-specific initialization exists, call it.
 	 * If not, call a CPU-specific one
 	 */
 	if (board_eth_init != __def_eth_init) {
 		if (board_eth_init(bis) < 0)
 			printf("Board Net Initialization Failed\n");
 	} else if (cpu_eth_init != __def_eth_init) {
 		if (cpu_eth_init(bis) < 0)
 			printf("CPU Net Initialization Failed\n");
 	} else
 		printf("Net Initialization Skipped\n");

 	if (!eth_devices) {
 		puts("No ethernet found.\n");
 		bootstage_error(BOOTSTAGE_ID_NET_ETH_START);
 	} else {
 		struct eth_device *dev = eth_devices;
 		char *ethprime = getenv("ethprime");

 		bootstage_mark(BOOTSTAGE_ID_NET_ETH_INIT);
 		do {
 			if (dev->index)
 				puts(", ");

 			printf("%s", dev->name);

 			if (ethprime && strcmp(dev->name, ethprime) == 0) {
 				eth_current = dev;
 				puts(" [PRIME]");
 			}

 			if (strchr(dev->name, ' '))
 				puts("\nWarning: eth device name has a space!"
 					"\n");

 			eth_write_hwaddr(dev, "eth", dev->index);

 			dev = dev->next;
 			num_devices++;
 		} while (dev != eth_devices);

 		eth_current_changed();
 		putc('\n');
 	}

 	return num_devices;
 }

 #ifdef CONFIG_MCAST_TFTP
 /* Multicast.
  * mcast_addr: multicast ipaddr from which multicast Mac is made
  * join: 1=join, 0=leave.
  */
 int eth_mcast_join(IPaddr_t mcast_ip, u8 join)
 {
 	u8 mcast_mac[6];
 	if (!eth_current || !eth_current->mcast)
 		return -1;
 	mcast_mac[5] = htonl(mcast_ip) & 0xff;
 	mcast_mac[4] = (htonl(mcast_ip)>>8) & 0xff;
 	mcast_mac[3] = (htonl(mcast_ip)>>16) & 0x7f;
 	mcast_mac[2] = 0x5e;
 	mcast_mac[1] = 0x0;
 	mcast_mac[0] = 0x1;
 	return eth_current->mcast(eth_current, mcast_mac, join);
 }

 /* the 'way' for ethernet-CRC-32. Spliced in from Linux lib/crc32.c
  * and this is the ethernet-crc method needed for TSEC -- and perhaps
  * some other adapter -- hash tables
  */
 #define CRCPOLY_LE 0xedb88320
 u32 ether_crc(size_t len, unsigned char const *p)
 {
 	int i;
 	u32 crc;
 	crc = ~0;
 	while (len--) {
 		crc ^= *p++;
 		for (i = 0; i < 8; i++)
 			crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
 	}
 	/* an reverse the bits, cuz of way they arrive -- last-first */
 	crc = (crc >> 16) | (crc << 16);
 	crc = (crc >> 8 & 0x00ff00ff) | (crc << 8 & 0xff00ff00);
 	crc = (crc >> 4 & 0x0f0f0f0f) | (crc << 4 & 0xf0f0f0f0);
 	crc = (crc >> 2 & 0x33333333) | (crc << 2 & 0xcccccccc);
 	crc = (crc >> 1 & 0x55555555) | (crc << 1 & 0xaaaaaaaa);
 	return crc;
 }

 #endif


 int eth_init(bd_t *bis)
 {
 	struct eth_device *old_current, *dev;

 	if (!eth_current) {
 		puts("No ethernet found.\n");
 		return -1;
 	}

 	/* Sync environment with network devices */
 	dev = eth_devices;
 	do {
 		uchar env_enetaddr[6];

 		if (eth_getenv_enetaddr_by_index("eth", dev->index,
 						 env_enetaddr))
 			memcpy(dev->enetaddr, env_enetaddr, 6);

 		dev = dev->next;
 	} while (dev != eth_devices);

 	old_current = eth_current;
 	do {
 		debug("Trying %s\n", eth_current->name);

 		if (eth_current->init(eth_current, bis) >= 0) {
 			eth_current->state = ETH_STATE_ACTIVE;

 			return 0;
 		}
 		debug("FAIL\n");

 		eth_try_another(0);
 	} while (old_current != eth_current);

 	return -1;
 }

 void eth_halt(void)
 {
 	if (!eth_current)
 		return;

 	eth_current->halt(eth_current);

 	eth_current->state = ETH_STATE_PASSIVE;
 }

 int eth_send(void *packet, int length)
 {
 	if (!eth_current)
 		return -1;

 	return eth_current->send(eth_current, packet, length);
 }

 int eth_rx(void)
 {
 	if (!eth_current)
 		return -1;

 	return eth_current->recv(eth_current);
 }

 #ifdef CONFIG_API
 static void eth_save_packet(void *packet, int length)
 {
 	char *p = packet;
 	int i;

 	if ((eth_rcv_last+1) % PKTBUFSRX == eth_rcv_current)
 		return;

 	if (PKTSIZE < length)
 		return;

 	for (i = 0; i < length; i++)
 		eth_rcv_bufs[eth_rcv_last].data[i] = p[i];

 	eth_rcv_bufs[eth_rcv_last].length = length;
 	eth_rcv_last = (eth_rcv_last + 1) % PKTBUFSRX;
 }

 int eth_receive(void *packet, int length)
 {
 	char *p = packet;
 	void *pp = push_packet;
 	int i;

 	if (eth_rcv_current == eth_rcv_last) {
 		push_packet = eth_save_packet;
 		eth_rx();
 		push_packet = pp;

 		if (eth_rcv_current == eth_rcv_last)
 			return -1;
 	}

 	length = min(eth_rcv_bufs[eth_rcv_current].length, length);

 	for (i = 0; i < length; i++)
 		p[i] = eth_rcv_bufs[eth_rcv_current].data[i];

 	eth_rcv_current = (eth_rcv_current + 1) % PKTBUFSRX;
 	return length;
 }
 #endif /* CONFIG_API */

 void eth_try_another(int first_restart)
 {
 	static struct eth_device *first_failed;
 	char *ethrotate;

 	/*
 	 * Do not rotate between network interfaces when
 	 * 'ethrotate' variable is set to 'no'.
 	 */
 	ethrotate = getenv("ethrotate");
 	if ((ethrotate != NULL) && (strcmp(ethrotate, "no") == 0))
 		return;

 	if (!eth_current)
 		return;

 	if (first_restart)
 		first_failed = eth_current;

 	eth_current = eth_current->next;

 	eth_current_changed();

 	if (first_failed == eth_current)
 		NetRestartWrap = 1;
 }

 void eth_set_current(void)
 {
 	static char *act;
 	static int  env_changed_id;
 	struct eth_device *old_current;
 	int	env_id;

 	if (!eth_current)	/* XXX no current */
 		return;

 	env_id = get_env_id();
 	if ((act == NULL) || (env_changed_id != env_id)) {
 		act = getenv("ethact");
 		env_changed_id = env_id;
 	}
 	if (act != NULL) {
 		old_current = eth_current;
 		do {
 			if (strcmp(eth_current->name, act) == 0)
 				return;
 			eth_current = eth_current->next;
 		} while (old_current != eth_current);
 	}

 	eth_current_changed();
 }

 char *eth_get_name(void)
 {
 	return eth_current ? eth_current->name : "unknown";
 }
	/*
	* (C) Copyright 2001-2010
	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

	#include <common.h>
	#include <command.h>
	#include <net.h>
	#include <miiphy.h>
	#include <phy.h>
	#include <asm/errno.h>

	void eth_parse_enetaddr(const char addr, uchar enetaddr)
	{
	char *end;
	int i;

	for (i = 0; i < 6; ++i) {
	enetaddr[i] = addr ? simple_strtoul(addr, &end, 16) : 0;
	if (addr)
	addr = (*end) ? end + 1 : end;
	}
	}

	int eth_getenv_enetaddr(char name, uchar enetaddr)
	{
	eth_parse_enetaddr(getenv(name), enetaddr);
	return is_valid_ether_addr(enetaddr);
	}

	int eth_setenv_enetaddr(char name, const uchar enetaddr)
	{
	char buf[20];

	sprintf(buf, "%pM", enetaddr);

	return setenv(name, buf);
	}

	int eth_getenv_enetaddr_by_index(const char *base_name, int index,
	uchar *enetaddr)
	{
	char enetvar[32];
	sprintf(enetvar, index ? "%s%daddr" : "%saddr", base_name, index);
	return eth_getenv_enetaddr(enetvar, enetaddr);
	}

	static inline int eth_setenv_enetaddr_by_index(const char *base_name, int index,
	uchar *enetaddr)
	{
	char enetvar[32];
	sprintf(enetvar, index ? "%s%daddr" : "%saddr", base_name, index);
	return eth_setenv_enetaddr(enetvar, enetaddr);
	}


	static int eth_mac_skip(int index)
	{
	char enetvar[15];
	char *skip_state;
	sprintf(enetvar, index ? "eth%dmacskip" : "ethmacskip", index);
	return ((skip_state = getenv(enetvar)) != NULL);
	}

	/*
	* CPU and board-specific Ethernet initializations. Aliased function
	* signals caller to move on
	*/
	static int __def_eth_init(bd_t *bis)
	{
	return -1;
	}
	int cpu_eth_init(bd_t *bis) __attribute__((weak, alias("__def_eth_init")));
	int board_eth_init(bd_t *bis) __attribute__((weak, alias("__def_eth_init")));

	#ifdef CONFIG_API
	static struct {
	uchar data[PKTSIZE];
	int length;
	} eth_rcv_bufs[PKTBUFSRX];

	static unsigned int eth_rcv_current, eth_rcv_last;
	#endif

	static struct eth_device *eth_devices;
	struct eth_device *eth_current;

	struct eth_device eth_get_dev_by_name(const char devname)
	{
	struct eth_device dev, target_dev;

	BUG_ON(devname == NULL);

	if (!eth_devices)
	return NULL;

	dev = eth_devices;
	target_dev = NULL;
	do {
	if (strcmp(devname, dev->name) == 0) {
	target_dev = dev;
	break;
	}
	dev = dev->next;
	} while (dev != eth_devices);

	return target_dev;
	}

	struct eth_device *eth_get_dev_by_index(int index)
	{
	struct eth_device dev, target_dev;

	if (!eth_devices)
	return NULL;

	dev = eth_devices;
	target_dev = NULL;
	do {
	if (dev->index == index) {
	target_dev = dev;
	break;
	}
	dev = dev->next;
	} while (dev != eth_devices);

	return target_dev;
	}

	int eth_get_dev_index(void)
	{
	if (!eth_current)
	return -1;

	return eth_current->index;
	}

	static void eth_current_changed(void)
	{
	char *act = getenv("ethact");
	/* update current ethernet name */
	if (eth_current) {
	if (act == NULL \|\| strcmp(act, eth_current->name) != 0)
	setenv("ethact", eth_current->name);
	}
	/*
	* remove the variable completely if there is no active
	* interface
	*/
	else if (act != NULL)
	setenv("ethact", NULL);
	}

	int eth_address_set(unsigned char *addr)
	{
	return memcmp(addr, "\0\0\0\0\0\0", 6);
	}

	int eth_write_hwaddr(struct eth_device dev, const char base_name,
	int eth_number)
	{
	unsigned char env_enetaddr[6];
	int ret = 0;

	eth_getenv_enetaddr_by_index(base_name, eth_number, env_enetaddr);

	if (eth_address_set(env_enetaddr)) {
	if (eth_address_set(dev->enetaddr) &&
	memcmp(dev->enetaddr, env_enetaddr, 6)) {
	printf("\nWarning: %s MAC addresses don't match:\n",
	dev->name);
	printf("Address in SROM is %pM\n",
	dev->enetaddr);
	printf("Address in environment is %pM\n",
	env_enetaddr);
	}

	memcpy(dev->enetaddr, env_enetaddr, 6);
	} else if (is_valid_ether_addr(dev->enetaddr)) {
	eth_setenv_enetaddr_by_index(base_name, eth_number,
	dev->enetaddr);
	printf("\nWarning: %s using MAC address from net device\n",
	dev->name);
	} else if (!(eth_address_set(dev->enetaddr))) {
	printf("\nError: %s address not set.\n",
	dev->name);
	return -EINVAL;
	}

	if (dev->write_hwaddr && !eth_mac_skip(eth_number)) {
	if (!is_valid_ether_addr(dev->enetaddr)) {
	printf("\nError: %s address %pM illegal value\n",
	dev->name, dev->enetaddr);
	return -EINVAL;
	}

	ret = dev->write_hwaddr(dev);
	if (ret)
	printf("\nWarning: %s failed to set MAC address\n", dev->name);
	}

	return ret;
	}

	int eth_register(struct eth_device *dev)
	{
	struct eth_device *d;
	static int index;

	assert(strlen(dev->name) < sizeof(dev->name));

	if (!eth_devices) {
	eth_current = eth_devices = dev;
	eth_current_changed();
	} else {
	for (d = eth_devices; d->next != eth_devices; d = d->next)
	;
	d->next = dev;
	}

	dev->state = ETH_STATE_INIT;
	dev->next = eth_devices;
	dev->index = index++;

	return 0;
	}

	int eth_unregister(struct eth_device *dev)
	{
	struct eth_device *cur;

	/* No device */
	if (!eth_devices)
	return -1;

	for (cur = eth_devices; cur->next != eth_devices && cur->next != dev;
	cur = cur->next)
	;

	/* Device not found */
	if (cur->next != dev)
	return -1;

	cur->next = dev->next;

	if (eth_devices == dev)
	eth_devices = dev->next == eth_devices ? NULL : dev->next;

	if (eth_current == dev) {
	eth_current = eth_devices;
	eth_current_changed();
	}

	return 0;
	}

	static void eth_env_init(bd_t *bis)
	{
	const char *s;

	if ((s = getenv("bootfile")) != NULL)
	copy_filename(BootFile, s, sizeof(BootFile));
	}

	int eth_initialize(bd_t *bis)
	{
	int num_devices = 0;
	eth_devices = NULL;
	eth_current = NULL;

	bootstage_mark(BOOTSTAGE_ID_NET_ETH_START);
	#if defined(CONFIG_MII) \|\| defined(CONFIG_CMD_MII) \|\| defined(CONFIG_PHYLIB)
	miiphy_init();
	#endif

	#ifdef CONFIG_PHYLIB
	phy_init();
	#endif

	eth_env_init(bis);

	/*
	* If board-specific initialization exists, call it.
	* If not, call a CPU-specific one
	*/
	if (board_eth_init != __def_eth_init) {
	if (board_eth_init(bis) < 0)
	printf("Board Net Initialization Failed\n");
	} else if (cpu_eth_init != __def_eth_init) {
	if (cpu_eth_init(bis) < 0)
	printf("CPU Net Initialization Failed\n");
	} else
	printf("Net Initialization Skipped\n");

	if (!eth_devices) {
	puts("No ethernet found.\n");
	bootstage_error(BOOTSTAGE_ID_NET_ETH_START);
	} else {
	struct eth_device *dev = eth_devices;
	char *ethprime = getenv("ethprime");

	bootstage_mark(BOOTSTAGE_ID_NET_ETH_INIT);
	do {
	if (dev->index)
	puts(", ");

	printf("%s", dev->name);

	if (ethprime && strcmp(dev->name, ethprime) == 0) {
	eth_current = dev;
	puts(" [PRIME]");
	}

	if (strchr(dev->name, ' '))
	puts("\nWarning: eth device name has a space!"
	"\n");

	eth_write_hwaddr(dev, "eth", dev->index);

	dev = dev->next;
	num_devices++;
	} while (dev != eth_devices);

	eth_current_changed();
	putc('\n');
	}

	return num_devices;
	}

	#ifdef CONFIG_MCAST_TFTP
	/* Multicast.
	* mcast_addr: multicast ipaddr from which multicast Mac is made
	* join: 1=join, 0=leave.
	*/
	int eth_mcast_join(IPaddr_t mcast_ip, u8 join)
	{
	u8 mcast_mac[6];
	if (!eth_current \|\| !eth_current->mcast)
	return -1;
	mcast_mac[5] = htonl(mcast_ip) & 0xff;
	mcast_mac[4] = (htonl(mcast_ip)>>8) & 0xff;
	mcast_mac[3] = (htonl(mcast_ip)>>16) & 0x7f;
	mcast_mac[2] = 0x5e;
	mcast_mac[1] = 0x0;
	mcast_mac[0] = 0x1;
	return eth_current->mcast(eth_current, mcast_mac, join);
	}

	/* the 'way' for ethernet-CRC-32. Spliced in from Linux lib/crc32.c
	* and this is the ethernet-crc method needed for TSEC -- and perhaps
	* some other adapter -- hash tables
	*/
	#define CRCPOLY_LE 0xedb88320
	u32 ether_crc(size_t len, unsigned char const *p)
	{
	int i;
	u32 crc;
	crc = ~0;
	while (len--) {
	crc ^= *p++;
	for (i = 0; i < 8; i++)
	crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
	}
	/* an reverse the bits, cuz of way they arrive -- last-first */
	crc = (crc >> 16) \| (crc << 16);
	crc = (crc >> 8 & 0x00ff00ff) \| (crc << 8 & 0xff00ff00);
	crc = (crc >> 4 & 0x0f0f0f0f) \| (crc << 4 & 0xf0f0f0f0);
	crc = (crc >> 2 & 0x33333333) \| (crc << 2 & 0xcccccccc);
	crc = (crc >> 1 & 0x55555555) \| (crc << 1 & 0xaaaaaaaa);
	return crc;
	}

	#endif


	int eth_init(bd_t *bis)
	{
	struct eth_device old_current, dev;

	if (!eth_current) {
	puts("No ethernet found.\n");
	return -1;
	}

	/* Sync environment with network devices */
	dev = eth_devices;
	do {
	uchar env_enetaddr[6];

	if (eth_getenv_enetaddr_by_index("eth", dev->index,
	env_enetaddr))
	memcpy(dev->enetaddr, env_enetaddr, 6);

	dev = dev->next;
	} while (dev != eth_devices);

	old_current = eth_current;
	do {
	debug("Trying %s\n", eth_current->name);

	if (eth_current->init(eth_current, bis) >= 0) {
	eth_current->state = ETH_STATE_ACTIVE;

	return 0;
	}
	debug("FAIL\n");

	eth_try_another(0);
	} while (old_current != eth_current);

	return -1;
	}

	void eth_halt(void)
	{
	if (!eth_current)
	return;

	eth_current->halt(eth_current);

	eth_current->state = ETH_STATE_PASSIVE;
	}

	int eth_send(void *packet, int length)
	{
	if (!eth_current)
	return -1;

	return eth_current->send(eth_current, packet, length);
	}

	int eth_rx(void)
	{
	if (!eth_current)
	return -1;

	return eth_current->recv(eth_current);
	}

	#ifdef CONFIG_API
	static void eth_save_packet(void *packet, int length)
	{
	char *p = packet;
	int i;

	if ((eth_rcv_last+1) % PKTBUFSRX == eth_rcv_current)
	return;

	if (PKTSIZE < length)
	return;

	for (i = 0; i < length; i++)
	eth_rcv_bufs[eth_rcv_last].data[i] = p[i];

	eth_rcv_bufs[eth_rcv_last].length = length;
	eth_rcv_last = (eth_rcv_last + 1) % PKTBUFSRX;
	}

	int eth_receive(void *packet, int length)
	{
	char *p = packet;
	void *pp = push_packet;
	int i;

	if (eth_rcv_current == eth_rcv_last) {
	push_packet = eth_save_packet;
	eth_rx();
	push_packet = pp;

	if (eth_rcv_current == eth_rcv_last)
	return -1;
	}

	length = min(eth_rcv_bufs[eth_rcv_current].length, length);

	for (i = 0; i < length; i++)
	p[i] = eth_rcv_bufs[eth_rcv_current].data[i];

	eth_rcv_current = (eth_rcv_current + 1) % PKTBUFSRX;
	return length;
	}
	#endif /* CONFIG_API */

	void eth_try_another(int first_restart)
	{
	static struct eth_device *first_failed;
	char *ethrotate;

	/*
	* Do not rotate between network interfaces when
	* 'ethrotate' variable is set to 'no'.
	*/
	ethrotate = getenv("ethrotate");
	if ((ethrotate != NULL) && (strcmp(ethrotate, "no") == 0))
	return;

	if (!eth_current)
	return;

	if (first_restart)
	first_failed = eth_current;

	eth_current = eth_current->next;

	eth_current_changed();

	if (first_failed == eth_current)
	NetRestartWrap = 1;
	}

	void eth_set_current(void)
	{
	static char *act;
	static int env_changed_id;
	struct eth_device *old_current;
	int env_id;

	if (!eth_current) /* XXX no current */
	return;

	env_id = get_env_id();
	if ((act == NULL) \|\| (env_changed_id != env_id)) {
	act = getenv("ethact");
	env_changed_id = env_id;
	}
	if (act != NULL) {
	old_current = eth_current;
	do {
	if (strcmp(eth_current->name, act) == 0)
	return;
	eth_current = eth_current->next;
	} while (old_current != eth_current);
	}

	eth_current_changed();
	}

	char *eth_get_name(void)
	{
	return eth_current ? eth_current->name : "unknown";
	}