/*-
 * Copyright (c) 2014, Alexander V. Chernikov
 * Copyright (c) 2020, Ryan Moeller <freqlabs@FreeBSD.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#define _WANT_SFF_8024_ID

#include <sys/types.h>
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>

#include <net/if.h>
#include <net/sff8436.h>
#include <net/sff8472.h>

#include <math.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <libifconfig.h>
#include <libifconfig_internal.h>
#include <libifconfig_sfp.h>
#include <libifconfig_sfp_tables_internal.h>

#define     SFF_8636_EXT_COMPLIANCE 0x80

struct i2c_info {
        struct ifreq ifr;
        ifconfig_handle_t *h;
        int error;              /* Store first error */
        enum sfp_id id;         /* Module type */
};

static uint8_t
find_zero_bit(const struct sfp_enum_metadata *table, int value, int sz)
{
        int v, m;

        for (v = 1, m = 1 << (8 * sz); v < m; v <<= 1) {
                if ((value & v) == 0)
                        continue;
                if (find_metadata(table, value & v) != NULL) {
                        return (value & v);
                }
        }
        return (0);
}

/*
 * Reads i2c data from opened kernel socket.
 */
static int
read_i2c(struct i2c_info *ii, uint8_t addr, uint8_t off, uint8_t len,
    uint8_t *buf)
{
        struct ifi2creq req;
        int i, l;

        if (ii->error != 0)
                return (ii->error);

        ii->ifr.ifr_data = (caddr_t)&req;

        i = 0;
        l = 0;
        memset(&req, 0, sizeof(req));
        req.dev_addr = addr;
        req.offset = off;
        req.len = len;

        while (len > 0) {
                l = MIN(sizeof(req.data), len);
                req.len = l;
                if (ifconfig_ioctlwrap(ii->h, AF_LOCAL, SIOCGI2C,
                    &ii->ifr) != 0) {
                        ii->error = errno;
                        return (errno);
                }

                memcpy(&buf[i], req.data, l);
                len -= l;
                i += l;
                req.offset += l;
        }

        return (0);
}

static int
i2c_info_init(struct i2c_info *ii, ifconfig_handle_t *h, const char *name)
{
        uint8_t id_byte;

        memset(ii, 0, sizeof(*ii));
        strlcpy(ii->ifr.ifr_name, name, sizeof(ii->ifr.ifr_name));
        ii->h = h;

        /*
         * Try to read byte 0 from i2c:
         * Both SFF-8472 and SFF-8436 use it as
         * 'identification byte'.
         * Stop reading status on zero as value -
         * this might happen in case of empty transceiver slot.
         */
        id_byte = 0;
        read_i2c(ii, SFF_8472_BASE, SFF_8472_ID, 1, &id_byte);
        if (ii->error != 0)
                return (-1);
        if (id_byte == 0) {
                h->error.errtype = OTHER;
                h->error.errcode = ENOENT;
                return (-1);
        }
        ii->id = id_byte;
        return (0);
}

static int
get_sfp_info(struct i2c_info *ii, struct ifconfig_sfp_info *sfp)
{
        uint8_t code;

        read_i2c(ii, SFF_8472_BASE, SFF_8472_ID, 1, &sfp->sfp_id);
        read_i2c(ii, SFF_8472_BASE, SFF_8472_CONNECTOR, 1, &sfp->sfp_conn);

        /* Use extended compliance code if it's valid */
        read_i2c(ii, SFF_8472_BASE, SFF_8472_TRANS, 1, &sfp->sfp_eth_ext);
        if (sfp->sfp_eth_ext == 0) {
                /* Next, check 10G Ethernet/IB CCs */
                read_i2c(ii, SFF_8472_BASE, SFF_8472_TRANS_START, 1, &code);
                sfp->sfp_eth_10g = find_zero_bit(sfp_eth_10g_table, code, 1);
                if (sfp->sfp_eth_10g == 0) {
                        /* No match. Try Ethernet 1G */
                        read_i2c(ii, SFF_8472_BASE, SFF_8472_TRANS_START + 3,
                            1, &code);
                        sfp->sfp_eth = find_zero_bit(sfp_eth_table, code, 1);
                }
        }

        return (ii->error);
}

static int
get_qsfp_info(struct i2c_info *ii, struct ifconfig_sfp_info *sfp)
{
        uint8_t code;

        read_i2c(ii, SFF_8436_BASE, SFF_8436_ID, 1, &sfp->sfp_id);
        read_i2c(ii, SFF_8436_BASE, SFF_8436_CONNECTOR, 1, &sfp->sfp_conn);

        read_i2c(ii, SFF_8436_BASE, SFF_8436_STATUS, 1, &sfp->sfp_rev);

        /* Check for extended specification compliance */
        read_i2c(ii, SFF_8436_BASE, SFF_8436_CODE_E1040100G, 1, &code);
        if (code & SFF_8636_EXT_COMPLIANCE) {
                read_i2c(ii, SFF_8436_BASE, SFF_8436_OPTIONS_START, 1,
                    &sfp->sfp_eth_ext);
                sfp->sfp_eth_1040g = code;
        } else {
                /* Check 10/40G Ethernet class only */
                sfp->sfp_eth_1040g =
                    find_zero_bit(sfp_eth_1040g_table, code, 1);
        }

        return (ii->error);
}

int
ifconfig_sfp_get_sfp_info(ifconfig_handle_t *h,
    const char *name, struct ifconfig_sfp_info *sfp)
{
        struct i2c_info ii;
        char buf[8];

        memset(sfp, 0, sizeof(*sfp));

        if (i2c_info_init(&ii, h, name) != 0)
                return (-1);

        /* Read bytes 3-10 at once */
        read_i2c(&ii, SFF_8472_BASE, SFF_8472_TRANS_START, 8, buf);
        if (ii.error != 0)
                return (ii.error);

        /* Check 10G ethernet first */
        sfp->sfp_eth_10g = find_zero_bit(sfp_eth_10g_table, buf[0], 1);
        if (sfp->sfp_eth_10g == 0) {
                /* No match. Try 1G */
                sfp->sfp_eth = find_zero_bit(sfp_eth_table, buf[3], 1);
        }
        sfp->sfp_fc_len = find_zero_bit(sfp_fc_len_table, buf[4], 1);
        sfp->sfp_fc_media = find_zero_bit(sfp_fc_media_table, buf[6], 1);
        sfp->sfp_fc_speed = find_zero_bit(sfp_fc_speed_table, buf[7], 1);
        sfp->sfp_cab_tech =
            find_zero_bit(sfp_cab_tech_table, (buf[4] << 8) | buf[5], 2);

        if (ifconfig_sfp_id_is_qsfp(ii.id))
                return (get_qsfp_info(&ii, sfp));
        return (get_sfp_info(&ii, sfp));
}

static size_t
channel_count(enum sfp_id id)
{
        /* TODO: other ids */
        switch (id) {
        case SFP_ID_UNKNOWN:
                return (0);
        case SFP_ID_QSFP:
        case SFP_ID_QSFPPLUS:
        case SFP_ID_QSFP28:
                return (4);
        default:
                return (1);
        }
}

size_t
ifconfig_sfp_channel_count(const struct ifconfig_sfp_info *sfp)
{
        return (channel_count(sfp->sfp_id));
}

/*
 * Print SFF-8472/SFF-8436 string to supplied buffer.
 * All (vendor-specific) strings are padded right with '0x20'.
 */
static void
get_sff_string(struct i2c_info *ii, uint8_t addr, uint8_t off, char *dst)
{
        read_i2c(ii, addr, off, SFF_VENDOR_STRING_SIZE, dst);
        dst += SFF_VENDOR_STRING_SIZE;
        do { *dst-- = '\0'; } while (*dst == 0x20);
}

static void
get_sff_date(struct i2c_info *ii, uint8_t addr, uint8_t off, char *dst)
{
        char buf[SFF_VENDOR_DATE_SIZE];

        read_i2c(ii, addr, off, SFF_VENDOR_DATE_SIZE, buf);
        sprintf(dst, "20%c%c-%c%c-%c%c", buf[0], buf[1], buf[2], buf[3],
            buf[4], buf[5]);
}

static int
get_sfp_vendor_info(struct i2c_info *ii, struct ifconfig_sfp_vendor_info *vi)
{
        get_sff_string(ii, SFF_8472_BASE, SFF_8472_VENDOR_START, vi->name);
        get_sff_string(ii, SFF_8472_BASE, SFF_8472_PN_START, vi->pn);
        get_sff_string(ii, SFF_8472_BASE, SFF_8472_SN_START, vi->sn);
        get_sff_date(ii, SFF_8472_BASE, SFF_8472_DATE_START, vi->date);
        return (ii->error);
}

static int
get_qsfp_vendor_info(struct i2c_info *ii, struct ifconfig_sfp_vendor_info *vi)
{
        get_sff_string(ii, SFF_8436_BASE, SFF_8436_VENDOR_START, vi->name);
        get_sff_string(ii, SFF_8436_BASE, SFF_8436_PN_START, vi->pn);
        get_sff_string(ii, SFF_8436_BASE, SFF_8436_SN_START, vi->sn);
        get_sff_date(ii, SFF_8436_BASE, SFF_8436_DATE_START, vi->date);
        return (ii->error);
}

int
ifconfig_sfp_get_sfp_vendor_info(ifconfig_handle_t *h,
    const char *name, struct ifconfig_sfp_vendor_info *vi)
{
        struct i2c_info ii;

        memset(vi, 0, sizeof(*vi));

        if (i2c_info_init(&ii, h, name) != 0)
                return (-1);

        if (ifconfig_sfp_id_is_qsfp(ii.id))
                return (get_qsfp_vendor_info(&ii, vi));
        return (get_sfp_vendor_info(&ii, vi));
}

/*
 * Converts internal temperature (SFF-8472, SFF-8436)
 * 16-bit unsigned value to human-readable representation:
 *
 * Internally measured Module temperature are represented
 * as a 16-bit signed twos complement value in increments of
 * 1/256 degrees Celsius, yielding a total range of –128C to +128C
 * that is considered valid between –40 and +125C.
 */
static double
get_sff_temp(struct i2c_info *ii, uint8_t addr, uint8_t off)
{
        double d;
        uint8_t buf[2];

        read_i2c(ii, addr, off, 2, buf);
        d = (double)buf[0];
        d += (double)buf[1] / 256;
        return (d);
}

/*
 * Retrieves supplied voltage (SFF-8472, SFF-8436).
 * 16-bit usigned value, treated as range 0..+6.55 Volts
 */
static double
get_sff_voltage(struct i2c_info *ii, uint8_t addr, uint8_t off)
{
        double d;
        uint8_t buf[2];

        read_i2c(ii, addr, off, 2, buf);
        d = (double)((buf[0] << 8) | buf[1]);
        return (d / 10000);
}

/*
 * The following conversions assume internally-calibrated data.
 * This is always true for SFF-8346, and explicitly checked for SFF-8472.
 */

double
power_mW(uint16_t power)
{
        /* Power is specified in units of 0.1 uW. */
        return (1.0 * power / 10000);
}

double
power_dBm(uint16_t power)
{
        return (10.0 * log10(power_mW(power)));
}

double
bias_mA(uint16_t bias)
{
        /* Bias current is specified in units of 2 uA. */
        return (1.0 * bias / 500);
}

static uint16_t
get_sff_channel(struct i2c_info *ii, uint8_t addr, uint8_t off)
{
        uint8_t buf[2];

        read_i2c(ii, addr, off, 2, buf);
        if (ii->error != 0)
                return (0);

        return ((buf[0] << 8) + buf[1]);
}

static int
get_sfp_status(struct i2c_info *ii, struct ifconfig_sfp_status *ss)
{
        uint8_t diag_type, flags;

        /* Read diagnostic monitoring type */
        read_i2c(ii, SFF_8472_BASE, SFF_8472_DIAG_TYPE, 1, (caddr_t)&diag_type);
        if (ii->error != 0)
                return (-1);

        /*
         * Read monitoring data IFF it is supplied AND is
         * internally calibrated
         */
        flags = SFF_8472_DDM_DONE | SFF_8472_DDM_INTERNAL;
        if ((diag_type & flags) != flags) {
                ii->h->error.errtype = OTHER;
                ii->h->error.errcode = ENXIO;
                return (-1);
        }

        ss->temp = get_sff_temp(ii, SFF_8472_DIAG, SFF_8472_TEMP);
        ss->voltage = get_sff_voltage(ii, SFF_8472_DIAG, SFF_8472_VCC);
        ss->channel = calloc(channel_count(ii->id), sizeof(*ss->channel));
        if (ss->channel == NULL) {
                ii->h->error.errtype = OTHER;
                ii->h->error.errcode = ENOMEM;
                return (-1);
        }
        ss->channel[0].rx = get_sff_channel(ii, SFF_8472_DIAG, SFF_8472_RX_POWER);
        ss->channel[0].tx = get_sff_channel(ii, SFF_8472_DIAG, SFF_8472_TX_BIAS);
        return (ii->error);
}

static uint32_t
get_qsfp_bitrate(struct i2c_info *ii)
{
        uint8_t code;
        uint32_t rate;

        code = 0;
        read_i2c(ii, SFF_8436_BASE, SFF_8436_BITRATE, 1, &code);
        rate = code * 100;
        if (code == 0xFF) {
                read_i2c(ii, SFF_8436_BASE, SFF_8636_BITRATE, 1, &code);
                rate = code * 250;
        }

        return (rate);
}

static int
get_qsfp_status(struct i2c_info *ii, struct ifconfig_sfp_status *ss)
{
        size_t channels;

        ss->temp = get_sff_temp(ii, SFF_8436_BASE, SFF_8436_TEMP);
        ss->voltage = get_sff_voltage(ii, SFF_8436_BASE, SFF_8436_VCC);
        channels = channel_count(ii->id);
        ss->channel = calloc(channels, sizeof(*ss->channel));
        if (ss->channel == NULL) {
                ii->h->error.errtype = OTHER;
                ii->h->error.errcode = ENOMEM;
                return (-1);
        }
        for (size_t chan = 0; chan < channels; ++chan) {
                uint8_t rxoffs = SFF_8436_RX_CH1_MSB + chan * sizeof(uint16_t);
                uint8_t txoffs = SFF_8436_TX_CH1_MSB + chan * sizeof(uint16_t);
                ss->channel[chan].rx =
                    get_sff_channel(ii, SFF_8436_BASE, rxoffs);
                ss->channel[chan].tx =
                    get_sff_channel(ii, SFF_8436_BASE, txoffs);
        }
        ss->bitrate = get_qsfp_bitrate(ii);
        return (ii->error);
}

int
ifconfig_sfp_get_sfp_status(ifconfig_handle_t *h, const char *name,
    struct ifconfig_sfp_status *ss)
{
        struct i2c_info ii;

        memset(ss, 0, sizeof(*ss));

        if (i2c_info_init(&ii, h, name) != 0)
                return (-1);

        if (ifconfig_sfp_id_is_qsfp(ii.id))
                return (get_qsfp_status(&ii, ss));
        return (get_sfp_status(&ii, ss));
}

void
ifconfig_sfp_free_sfp_status(struct ifconfig_sfp_status *ss)
{
        if (ss != NULL)
                free(ss->channel);
}

static const char *
sfp_id_string_alt(uint8_t value)
{
        const char *id;

        if (value <= SFF_8024_ID_LAST)
                id = sff_8024_id[value];
        else if (value > 0x80)
                id = "Vendor specific";
        else
                id = "Reserved";

        return (id);
}

static const char *
sfp_conn_string_alt(uint8_t value)
{
        const char *conn;

        if (value >= 0x0D && value <= 0x1F)
                conn = "Unallocated";
        else if (value >= 0x24 && value <= 0x7F)
                conn = "Unallocated";
        else
                conn = "Vendor specific";

        return (conn);
}

void
ifconfig_sfp_get_sfp_info_strings(const struct ifconfig_sfp_info *sfp,
    struct ifconfig_sfp_info_strings *strings)
{
        get_sfp_info_strings(sfp, strings);
        if (strings->sfp_id == NULL)
                strings->sfp_id = sfp_id_string_alt(sfp->sfp_id);
        if (strings->sfp_conn == NULL)
                strings->sfp_conn = sfp_conn_string_alt(sfp->sfp_conn);
        if (strings->sfp_rev == NULL)
                strings->sfp_rev = "Unallocated";
}

const char *
ifconfig_sfp_physical_spec(const struct ifconfig_sfp_info *sfp,
    const struct ifconfig_sfp_info_strings *strings)
{
        switch (sfp->sfp_id) {
        case SFP_ID_UNKNOWN:
                break;
        case SFP_ID_QSFP:
        case SFP_ID_QSFPPLUS:
        case SFP_ID_QSFP28:
                if (sfp->sfp_eth_1040g & SFP_ETH_1040G_EXTENDED)
                        return (strings->sfp_eth_ext);
                else if (sfp->sfp_eth_1040g)
                        return (strings->sfp_eth_1040g);
                break;
        default:
                if (sfp->sfp_eth_ext)
                        return (strings->sfp_eth_ext);
                else if (sfp->sfp_eth_10g)
                        return (strings->sfp_eth_10g);
                else if (sfp->sfp_eth)
                        return (strings->sfp_eth);
                break;
        }
        return ("Unknown");
}

int
ifconfig_sfp_get_sfp_dump(ifconfig_handle_t *h, const char *name,
    struct ifconfig_sfp_dump *dump)
{
        struct i2c_info ii;
        uint8_t *buf = dump->data;

        memset(dump->data, 0, sizeof(dump->data));

        if (i2c_info_init(&ii, h, name) != 0)
                return (-1);

        if (ifconfig_sfp_id_is_qsfp(ii.id)) {
                read_i2c(&ii, SFF_8436_BASE, QSFP_DUMP0_START, QSFP_DUMP0_SIZE,
                    buf + QSFP_DUMP0_START);
                read_i2c(&ii, SFF_8436_BASE, QSFP_DUMP1_START, QSFP_DUMP1_SIZE,
                    buf + QSFP_DUMP1_START);
        } else {
                read_i2c(&ii, SFF_8472_BASE, SFP_DUMP_START, SFP_DUMP_SIZE,
                    buf + SFP_DUMP_START);
        }

        return (ii.error != 0 ? -1 : 0);
}

size_t
ifconfig_sfp_dump_region_count(const struct ifconfig_sfp_dump *dp)
{
        uint8_t id_byte = dp->data[0];

        switch ((enum sfp_id)id_byte) {
        case SFP_ID_UNKNOWN:
                return (0);
        case SFP_ID_QSFP:
        case SFP_ID_QSFPPLUS:
        case SFP_ID_QSFP28:
                return (2);
        default:
                return (1);
        }
}