[people/ms/u-boot.git] / net / eth.c

/*
 * (C) Copyright 2001-2015
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 * Joe Hershberger, National Instruments
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <command.h>
#include <dm.h>
#include <environment.h>
#include <net.h>
#include <miiphy.h>
#include <phy.h>
#include <asm/errno.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>

DECLARE_GLOBAL_DATA_PTR;

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(const char *name, uchar *enetaddr)
{
        eth_parse_enetaddr(getenv(name), enetaddr);
        return is_valid_ethaddr(enetaddr);
}

int eth_setenv_enetaddr(const 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);
        skip_state = getenv(enetvar);
        return skip_state != NULL;
}

static void eth_current_changed(void);

/*
 * 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")));

static void eth_common_init(void)
{
        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

        /*
         * 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(gd->bd) < 0)
                        printf("Board Net Initialization Failed\n");
        } else if (cpu_eth_init != __def_eth_init) {
                if (cpu_eth_init(gd->bd) < 0)
                        printf("CPU Net Initialization Failed\n");
        } else {
#ifndef CONFIG_DM_ETH
                printf("Net Initialization Skipped\n");
#endif
        }
}

#ifdef CONFIG_DM_ETH
/**
 * struct eth_device_priv - private structure for each Ethernet device
 *
 * @state: The state of the Ethernet MAC driver (defined by enum eth_state_t)
 */
struct eth_device_priv {
        enum eth_state_t state;
};

/**
 * struct eth_uclass_priv - The structure attached to the uclass itself
 *
 * @current: The Ethernet device that the network functions are using
 */
struct eth_uclass_priv {
        struct udevice *current;
};

/* eth_errno - This stores the most recent failure code from DM functions */
static int eth_errno;

static struct eth_uclass_priv *eth_get_uclass_priv(void)
{
        struct uclass *uc;

        uclass_get(UCLASS_ETH, &uc);
        assert(uc);
        return uc->priv;
}

static void eth_set_current_to_next(void)
{
        struct eth_uclass_priv *uc_priv;

        uc_priv = eth_get_uclass_priv();
        if (uc_priv->current)
                uclass_next_device(&uc_priv->current);
        if (!uc_priv->current)
                uclass_first_device(UCLASS_ETH, &uc_priv->current);
}

/*
 * Typically this will simply return the active device.
 * In the case where the most recent active device was unset, this will attempt
 * to return the first device. If that device doesn't exist or fails to probe,
 * this function will return NULL.
 */
struct udevice *eth_get_dev(void)
{
        struct eth_uclass_priv *uc_priv;

        uc_priv = eth_get_uclass_priv();
        if (!uc_priv->current)
                eth_errno = uclass_first_device(UCLASS_ETH,
                                    &uc_priv->current);
        return uc_priv->current;
}

/*
 * Typically this will just store a device pointer.
 * In case it was not probed, we will attempt to do so.
 * dev may be NULL to unset the active device.
 */
static void eth_set_dev(struct udevice *dev)
{
        if (dev && !device_active(dev)) {
                eth_errno = device_probe(dev);
                if (eth_errno)
                        dev = NULL;
        }

        eth_get_uclass_priv()->current = dev;
}

/*
 * Find the udevice that either has the name passed in as devname or has an
 * alias named devname.
 */
struct udevice *eth_get_dev_by_name(const char *devname)
{
        int seq = -1;
        char *endp = NULL;
        const char *startp = NULL;
        struct udevice *it;
        struct uclass *uc;
        int len = strlen("eth");

        /* Must be longer than 3 to be an alias */
        if (!strncmp(devname, "eth", len) && strlen(devname) > len) {
                startp = devname + len;
                seq = simple_strtoul(startp, &endp, 10);
        }

        uclass_get(UCLASS_ETH, &uc);
        uclass_foreach_dev(it, uc) {
                /*
                 * We need the seq to be valid, so try to probe it.
                 * If the probe fails, the seq will not match since it will be
                 * -1 instead of what we are looking for.
                 * We don't care about errors from probe here. Either they won't
                 * match an alias or it will match a literal name and we'll pick
                 * up the error when we try to probe again in eth_set_dev().
                 */
                if (device_probe(it))
                        continue;
                /* Check for the name or the sequence number to match */
                if (strcmp(it->name, devname) == 0 ||
                    (endp > startp && it->seq == seq))
                        return it;
        }

        return NULL;
}

unsigned char *eth_get_ethaddr(void)
{
        struct eth_pdata *pdata;

        if (eth_get_dev()) {
                pdata = eth_get_dev()->platdata;
                return pdata->enetaddr;
        }

        return NULL;
}

/* Set active state without calling start on the driver */
int eth_init_state_only(void)
{
        struct udevice *current;
        struct eth_device_priv *priv;

        current = eth_get_dev();
        if (!current || !device_active(current))
                return -EINVAL;

        priv = current->uclass_priv;
        priv->state = ETH_STATE_ACTIVE;

        return 0;
}

/* Set passive state without calling stop on the driver */
void eth_halt_state_only(void)
{
        struct udevice *current;
        struct eth_device_priv *priv;

        current = eth_get_dev();
        if (!current || !device_active(current))
                return;

        priv = current->uclass_priv;
        priv->state = ETH_STATE_PASSIVE;
}

int eth_get_dev_index(void)
{
        if (eth_get_dev())
                return eth_get_dev()->seq;
        return -1;
}

static int eth_write_hwaddr(struct udevice *dev)
{
        struct eth_pdata *pdata = dev->platdata;
        int ret = 0;

        if (!dev || !device_active(dev))
                return -EINVAL;

        /* seq is valid since the device is active */
        if (eth_get_ops(dev)->write_hwaddr && !eth_mac_skip(dev->seq)) {
                if (!is_valid_ethaddr(pdata->enetaddr)) {
                        printf("\nError: %s address %pM illegal value\n",
                               dev->name, pdata->enetaddr);
                        return -EINVAL;
                }

                /*
                 * Drivers are allowed to decide not to implement this at
                 * run-time. E.g. Some devices may use it and some may not.
                 */
                ret = eth_get_ops(dev)->write_hwaddr(dev);
                if (ret == -ENOSYS)
                        ret = 0;
                if (ret)
                        printf("\nWarning: %s failed to set MAC address\n",
                               dev->name);
        }

        return ret;
}

static int on_ethaddr(const char *name, const char *value, enum env_op op,
        int flags)
{
        int index;
        int retval;
        struct udevice *dev;

        /* look for an index after "eth" */
        index = simple_strtoul(name + 3, NULL, 10);

        retval = uclass_find_device_by_seq(UCLASS_ETH, index, false, &dev);
        if (!retval) {
                struct eth_pdata *pdata = dev->platdata;
                switch (op) {
                case env_op_create:
                case env_op_overwrite:
                        eth_parse_enetaddr(value, pdata->enetaddr);
                        break;
                case env_op_delete:
                        memset(pdata->enetaddr, 0, 6);
                }
        }

        return 0;
}
U_BOOT_ENV_CALLBACK(ethaddr, on_ethaddr);

int eth_init(void)
{
        char *ethact = getenv("ethact");
        char *ethrotate = getenv("ethrotate");
        struct udevice *current = NULL;
        struct udevice *old_current;
        int ret = -ENODEV;

        /*
         * When 'ethrotate' variable is set to 'no' and 'ethact' variable
         * is already set to an ethernet device, we should stick to 'ethact'.
         */
        if ((ethrotate != NULL) && (strcmp(ethrotate, "no") == 0)) {
                if (ethact) {
                        current = eth_get_dev_by_name(ethact);
                        if (!current)
                                return -EINVAL;
                }
        }

        if (!current) {
                current = eth_get_dev();
                if (!current) {
                        printf("No ethernet found.\n");
                        return -ENODEV;
                }
        }

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

                        if (device_active(current)) {
                                ret = eth_get_ops(current)->start(current);
                                if (ret >= 0) {
                                        struct eth_device_priv *priv =
                                                current->uclass_priv;

                                        priv->state = ETH_STATE_ACTIVE;
                                        return 0;
                                }
                        } else {
                                ret = eth_errno;
                        }

                        debug("FAIL\n");
                } else {
                        debug("PROBE FAIL\n");
                }

                /*
                 * If ethrotate is enabled, this will change "current",
                 * otherwise we will drop out of this while loop immediately
                 */
                eth_try_another(0);
                /* This will ensure the new "current" attempted to probe */
                current = eth_get_dev();
        } while (old_current != current);

        return ret;
}

void eth_halt(void)
{
        struct udevice *current;
        struct eth_device_priv *priv;

        current = eth_get_dev();
        if (!current || !device_active(current))
                return;

        eth_get_ops(current)->stop(current);
        priv = current->uclass_priv;
        priv->state = ETH_STATE_PASSIVE;
}

int eth_is_active(struct udevice *dev)
{
        struct eth_device_priv *priv;

        if (!dev || !device_active(dev))
                return 0;

        priv = dev_get_uclass_priv(dev);
        return priv->state == ETH_STATE_ACTIVE;
}

int eth_send(void *packet, int length)
{
        struct udevice *current;
        int ret;

        current = eth_get_dev();
        if (!current)
                return -ENODEV;

        if (!device_active(current))
                return -EINVAL;

        ret = eth_get_ops(current)->send(current, packet, length);
        if (ret < 0) {
                /* We cannot completely return the error at present */
                debug("%s: send() returned error %d\n", __func__, ret);
        }
        return ret;
}

int eth_rx(void)
{
        struct udevice *current;
        uchar *packet;
        int flags;
        int ret;
        int i;

        current = eth_get_dev();
        if (!current)
                return -ENODEV;

        if (!device_active(current))
                return -EINVAL;

        /* Process up to 32 packets at one time */
        flags = ETH_RECV_CHECK_DEVICE;
        for (i = 0; i < 32; i++) {
                ret = eth_get_ops(current)->recv(current, flags, &packet);
                flags = 0;
                if (ret > 0)
                        net_process_received_packet(packet, ret);
                if (ret >= 0 && eth_get_ops(current)->free_pkt)
                        eth_get_ops(current)->free_pkt(current, packet, ret);
                if (ret <= 0)
                        break;
        }
        if (ret == -EAGAIN)
                ret = 0;
        if (ret < 0) {
                /* We cannot completely return the error at present */
                debug("%s: recv() returned error %d\n", __func__, ret);
        }
        return ret;
}

int eth_initialize(void)
{
        int num_devices = 0;
        struct udevice *dev;

        eth_common_init();

        /*
         * Devices need to write the hwaddr even if not started so that Linux
         * will have access to the hwaddr that u-boot stored for the device.
         * This is accomplished by attempting to probe each device and calling
         * their write_hwaddr() operation.
         */
        uclass_first_device(UCLASS_ETH, &dev);
        if (!dev) {
                printf("No ethernet found.\n");
                bootstage_error(BOOTSTAGE_ID_NET_ETH_START);
        } else {
                char *ethprime = getenv("ethprime");
                struct udevice *prime_dev = NULL;

                if (ethprime)
                        prime_dev = eth_get_dev_by_name(ethprime);
                if (prime_dev) {
                        eth_set_dev(prime_dev);
                        eth_current_changed();
                } else {
                        eth_set_dev(NULL);
                }

                bootstage_mark(BOOTSTAGE_ID_NET_ETH_INIT);
                do {
                        if (num_devices)
                                printf(", ");

                        printf("eth%d: %s", dev->seq, dev->name);

                        if (ethprime && dev == prime_dev)
                                printf(" [PRIME]");

                        eth_write_hwaddr(dev);

                        uclass_next_device(&dev);
                        num_devices++;
                } while (dev);

                putc('\n');
        }

        return num_devices;
}

static int eth_post_bind(struct udevice *dev)
{
        if (strchr(dev->name, ' ')) {
                printf("\nError: eth device name \"%s\" has a space!\n",
                       dev->name);
                return -EINVAL;
        }

        return 0;
}

static int eth_pre_unbind(struct udevice *dev)
{
        /* Don't hang onto a pointer that is going away */
        if (dev == eth_get_uclass_priv()->current)
                eth_set_dev(NULL);

        return 0;
}

static int eth_post_probe(struct udevice *dev)
{
        struct eth_device_priv *priv = dev->uclass_priv;
        struct eth_pdata *pdata = dev->platdata;
        unsigned char env_enetaddr[6];

#if defined(CONFIG_NEEDS_MANUAL_RELOC)
        struct eth_ops *ops = eth_get_ops(dev);
        static int reloc_done;

        if (!reloc_done) {
                if (ops->start)
                        ops->start += gd->reloc_off;
                if (ops->send)
                        ops->send += gd->reloc_off;
                if (ops->recv)
                        ops->recv += gd->reloc_off;
                if (ops->free_pkt)
                        ops->free_pkt += gd->reloc_off;
                if (ops->stop)
                        ops->stop += gd->reloc_off;
#ifdef CONFIG_MCAST_TFTP
                if (ops->mcast)
                        ops->mcast += gd->reloc_off;
#endif
                if (ops->write_hwaddr)
                        ops->write_hwaddr += gd->reloc_off;
                if (ops->read_rom_hwaddr)
                        ops->read_rom_hwaddr += gd->reloc_off;

                reloc_done++;
        }
#endif

        priv->state = ETH_STATE_INIT;

        /* Check if the device has a MAC address in ROM */
        if (eth_get_ops(dev)->read_rom_hwaddr)
                eth_get_ops(dev)->read_rom_hwaddr(dev);

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

                /* Override the ROM MAC address */
                memcpy(pdata->enetaddr, env_enetaddr, 6);
        } else if (is_valid_ethaddr(pdata->enetaddr)) {
                eth_setenv_enetaddr_by_index("eth", dev->seq, pdata->enetaddr);
                printf("\nWarning: %s using MAC address from ROM\n",
                       dev->name);
        } else if (is_zero_ethaddr(pdata->enetaddr)) {
#ifdef CONFIG_NET_RANDOM_ETHADDR
                net_random_ethaddr(pdata->enetaddr);
                printf("\nWarning: %s (eth%d) using random MAC address - %pM\n",
                       dev->name, dev->seq, pdata->enetaddr);
#else
                printf("\nError: %s address not set.\n",
                       dev->name);
                return -EINVAL;
#endif
        }

        return 0;
}

static int eth_pre_remove(struct udevice *dev)
{
        struct eth_pdata *pdata = dev->platdata;

        eth_get_ops(dev)->stop(dev);

        /* clear the MAC address */
        memset(pdata->enetaddr, 0, 6);

        return 0;
}

UCLASS_DRIVER(eth) = {
        .name           = "eth",
        .id             = UCLASS_ETH,
        .post_bind      = eth_post_bind,
        .pre_unbind     = eth_pre_unbind,
        .post_probe     = eth_post_probe,
        .pre_remove     = eth_pre_remove,
        .priv_auto_alloc_size = sizeof(struct eth_uclass_priv),
        .per_device_auto_alloc_size = sizeof(struct eth_device_priv),
        .flags          = DM_UC_FLAG_SEQ_ALIAS,
};
#endif /* #ifdef CONFIG_DM_ETH */

#ifndef CONFIG_DM_ETH

#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;

static void eth_set_current_to_next(void)
{
        eth_current = eth_current->next;
}

static void eth_set_dev(struct eth_device *dev)
{
        eth_current = dev;
}

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 int on_ethaddr(const char *name, const char *value, enum env_op op,
        int flags)
{
        int index;
        struct eth_device *dev;

        if (!eth_devices)
                return 0;

        /* look for an index after "eth" */
        index = simple_strtoul(name + 3, NULL, 10);

        dev = eth_devices;
        do {
                if (dev->index == index) {
                        switch (op) {
                        case env_op_create:
                        case env_op_overwrite:
                                eth_parse_enetaddr(value, dev->enetaddr);
                                break;
                        case env_op_delete:
                                memset(dev->enetaddr, 0, 6);
                        }
                }
                dev = dev->next;
        } while (dev != eth_devices);

        return 0;
}
U_BOOT_ENV_CALLBACK(ethaddr, on_ethaddr);

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 (!is_zero_ethaddr(env_enetaddr)) {
                if (!is_zero_ethaddr(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_ethaddr(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 (is_zero_ethaddr(dev->enetaddr)) {
#ifdef CONFIG_NET_RANDOM_ETHADDR
                net_random_ethaddr(dev->enetaddr);
                printf("\nWarning: %s (eth%d) using random MAC address - %pM\n",
                       dev->name, eth_number, dev->enetaddr);
#else
                printf("\nError: %s address not set.\n",
                       dev->name);
                return -EINVAL;
#endif
        }

        if (dev->write_hwaddr && !eth_mac_skip(eth_number)) {
                if (!is_valid_ethaddr(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_devices = dev;
                eth_current = 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 -ENODEV;

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

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

        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;
}

int eth_initialize(void)
{
        int num_devices = 0;

        eth_devices = NULL;
        eth_current = NULL;
        eth_common_init();

        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(struct in_addr mcast_ip, int join)
{
        u8 mcast_mac[6];
        if (!eth_current || !eth_current->mcast)
                return -1;
        mcast_mac[5] = htonl(mcast_ip.s_addr) & 0xff;
        mcast_mac[4] = (htonl(mcast_ip.s_addr)>>8) & 0xff;
        mcast_mac[3] = (htonl(mcast_ip.s_addr)>>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(void)
{
        struct eth_device *old_current;

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

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

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

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

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

        return -ETIMEDOUT;
}

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

        eth_current->halt(eth_current);

        eth_current->state = ETH_STATE_PASSIVE;
}

int eth_is_active(struct eth_device *dev)
{
        return dev && dev->state == ETH_STATE_ACTIVE;
}

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

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

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

        return eth_current->recv(eth_current);
}
#endif /* ifndef CONFIG_DM_ETH */

#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 */

static void eth_current_changed(void)
{
        char *act = getenv("ethact");
        char *ethrotate;

        /*
         * The call to eth_get_dev() below has a side effect of rotating
         * ethernet device if uc_priv->current == NULL. This is not what
         * we want when 'ethrotate' variable is 'no'.
         */
        ethrotate = getenv("ethrotate");
        if ((ethrotate != NULL) && (strcmp(ethrotate, "no") == 0))
                return;

        /* update current ethernet name */
        if (eth_get_dev()) {
                if (act == NULL || strcmp(act, eth_get_name()) != 0)
                        setenv("ethact", eth_get_name());
        }
        /*
         * remove the variable completely if there is no active
         * interface
         */
        else if (act != NULL)
                setenv("ethact", NULL);
}

void eth_try_another(int first_restart)
{
        static void *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_get_dev())
                return;

        if (first_restart)
                first_failed = eth_get_dev();

        eth_set_current_to_next();

        eth_current_changed();

        if (first_failed == eth_get_dev())
                net_restart_wrap = 1;
}

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

        env_id = get_env_id();
        if ((act == NULL) || (env_changed_id != env_id)) {
                act = getenv("ethact");
                env_changed_id = env_id;
        }

        if (act == NULL) {
                char *ethprime = getenv("ethprime");
                void *dev = NULL;

                if (ethprime)
                        dev = eth_get_dev_by_name(ethprime);
                if (dev)
                        eth_set_dev(dev);
                else
                        eth_set_dev(NULL);
        } else {
                eth_set_dev(eth_get_dev_by_name(act));
        }

        eth_current_changed();
}

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