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

#include <common.h>
#include <dm.h>
#include <env.h>
#include <net.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#include <net/pcap.h>
#include "eth_internal.h"

DECLARE_GLOBAL_DATA_PTR;

/**
 * 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;
}

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.
 */
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;
        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)) {
                pdata = dev->platdata;
                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:
                        string_to_enetaddr(value, pdata->enetaddr);
                        eth_write_hwaddr(dev);
                        break;
                case env_op_delete:
                        memset(pdata->enetaddr, 0, ARP_HLEN);
                }
        }

        return 0;
}
U_BOOT_ENV_CALLBACK(ethaddr, on_ethaddr);

int eth_init(void)
{
        char *ethact = env_get("ethact");
        char *ethrotate = env_get("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 || !eth_is_active(current))
                return;

        eth_get_ops(current)->stop(current);
        priv = current->uclass_priv;
        if (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 (!eth_is_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);
        }
#if defined(CONFIG_CMD_PCAP)
        if (ret >= 0)
                pcap_post(packet, length, true);
#endif
        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 (!eth_is_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_check(UCLASS_ETH, &dev);
        if (!dev) {
                printf("No ethernet found.\n");
                bootstage_error(BOOTSTAGE_ID_NET_ETH_START);
        } else {
                char *ethprime = env_get("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 (dev->seq != -1) {
                                if (num_devices)
                                        printf(", ");

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

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

                        eth_write_hwaddr(dev);

                        if (dev->seq != -1)
                                num_devices++;
                        uclass_next_device_check(&dev);
                } while (dev);

                if (!num_devices)
                        printf("No ethernet found.\n");
                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 bool eth_dev_get_mac_address(struct udevice *dev, u8 mac[ARP_HLEN])
{
#if IS_ENABLED(CONFIG_OF_CONTROL)
        const uint8_t *p;

        p = dev_read_u8_array_ptr(dev, "mac-address", ARP_HLEN);
        if (!p)
                p = dev_read_u8_array_ptr(dev, "local-mac-address", ARP_HLEN);

        if (!p)
                return false;

        memcpy(mac, p, ARP_HLEN);

        return true;
#else
        return false;
#endif
}

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[ARP_HLEN];
        const char *source = "DT";

#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;
                if (ops->mcast)
                        ops->mcast += gd->reloc_off;
                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 valid MAC address in device tree */
        if (!eth_dev_get_mac_address(dev, pdata->enetaddr) ||
            !is_valid_ethaddr(pdata->enetaddr)) {
                source = "ROM";
                /* 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_env_get_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, ARP_HLEN)) {
                        printf("\nWarning: %s MAC addresses don't match:\n",
                               dev->name);
                        printf("Address in %s is\t\t%pM\n",
                               source, pdata->enetaddr);
                        printf("Address in environment is\t%pM\n",
                               env_enetaddr);
                }

                /* Override the ROM MAC address */
                memcpy(pdata->enetaddr, env_enetaddr, ARP_HLEN);
        } else if (is_valid_ethaddr(pdata->enetaddr)) {
                eth_env_set_enetaddr_by_index("eth", dev->seq, pdata->enetaddr);
                printf("\nWarning: %s using MAC address from %s\n",
                       dev->name, source);
        } else if (is_zero_ethaddr(pdata->enetaddr) ||
                   !is_valid_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
        }

        eth_write_hwaddr(dev);

        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, ARP_HLEN);

        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,
};