// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright 2021 Gateworks Corporation
 */

#include <common.h>
#include <command.h>
#include <hang.h>
#include <hexdump.h>
#include <i2c.h>
#include <linux/delay.h>
#include <dm/uclass.h>

#include "gsc.h"

DECLARE_GLOBAL_DATA_PTR;

struct venice_board_info som_info;
struct venice_board_info base_info;
char venice_model[32];
uint32_t venice_serial;

/* return a mac address from EEPROM info */
int gsc_getmac(int index, uint8_t *address)
{
        int i, j;
        u32 maclow, machigh;
        u64 mac;

        j = 0;
        if (som_info.macno) {
                maclow = som_info.mac[5];
                maclow |= som_info.mac[4] << 8;
                maclow |= som_info.mac[3] << 16;
                maclow |= som_info.mac[2] << 24;
                machigh = som_info.mac[1];
                machigh |= som_info.mac[0] << 8;
                mac = machigh;
                mac <<= 32;
                mac |= maclow;
                for (i = 0; i < som_info.macno; i++, j++) {
                        if (index == j)
                                goto out;
                }
        }

        maclow = base_info.mac[5];
        maclow |= base_info.mac[4] << 8;
        maclow |= base_info.mac[3] << 16;
        maclow |= base_info.mac[2] << 24;
        machigh = base_info.mac[1];
        machigh |= base_info.mac[0] << 8;
        mac = machigh;
        mac <<= 32;
        mac |= maclow;
        for (i = 0; i < base_info.macno; i++, j++) {
                if (index == j)
                        goto out;
        }

        return -EINVAL;

out:
        mac += i;
        address[0] = (mac >> 40) & 0xff;
        address[1] = (mac >> 32) & 0xff;
        address[2] = (mac >> 24) & 0xff;
        address[3] = (mac >> 16) & 0xff;
        address[4] = (mac >> 8) & 0xff;
        address[5] = (mac >> 0) & 0xff;

        return 0;
}

/* System Controller registers */
enum {
        GSC_SC_CTRL0            = 0,
        GSC_SC_CTRL1            = 1,
        GSC_SC_STATUS           = 10,
        GSC_SC_FWCRC            = 12,
        GSC_SC_FWVER            = 14,
        GSC_SC_WP               = 15,
        GSC_SC_RST_CAUSE        = 16,
        GSC_SC_THERM_PROTECT    = 19,
};

/* System Controller Control1 bits */
enum {
        GSC_SC_CTRL1_WDTIME     = 4, /* 1 = 60s timeout, 0 = 30s timeout */
        GSC_SC_CTRL1_WDEN       = 5, /* 1 = enable, 0 = disable */
        GSC_SC_CTRL1_BOOT_CHK   = 6, /* 1 = enable alt boot check */
        GSC_SC_CTRL1_WDDIS      = 7, /* 1 = disable boot watchdog */
};

/* System Controller Interrupt bits */
enum {
        GSC_SC_IRQ_PB           = 0, /* Pushbutton switch */
        GSC_SC_IRQ_SECURE       = 1, /* Secure Key erase operation complete */
        GSC_SC_IRQ_EEPROM_WP    = 2, /* EEPROM write violation */
        GSC_SC_IRQ_GPIO         = 4, /* GPIO change */
        GSC_SC_IRQ_TAMPER       = 5, /* Tamper detect */
        GSC_SC_IRQ_WATCHDOG     = 6, /* Watchdog trip */
        GSC_SC_IRQ_PBLONG       = 7, /* Pushbutton long hold */
};

/* System Controller WP bits */
enum {
        GSC_SC_WP_ALL           = 0, /* Write Protect All EEPROM regions */
        GSC_SC_WP_BOARDINFO     = 1, /* Write Protect Board Info region */
};

/* System Controller Reset Cause */
enum {
        GSC_SC_RST_CAUSE_VIN            = 0,
        GSC_SC_RST_CAUSE_PB             = 1,
        GSC_SC_RST_CAUSE_WDT            = 2,
        GSC_SC_RST_CAUSE_CPU            = 3,
        GSC_SC_RST_CAUSE_TEMP_LOCAL     = 4,
        GSC_SC_RST_CAUSE_TEMP_REMOTE    = 5,
        GSC_SC_RST_CAUSE_SLEEP          = 6,
        GSC_SC_RST_CAUSE_BOOT_WDT       = 7,
        GSC_SC_RST_CAUSE_BOOT_WDT_MAN   = 8,
        GSC_SC_RST_CAUSE_SOFT_PWR       = 9,
        GSC_SC_RST_CAUSE_MAX            = 10,
};

#include <dm/device.h>
static struct udevice *gsc_get_dev(int busno, int slave)
{
        struct udevice *dev, *bus;
        int ret;

        ret = uclass_get_device_by_seq(UCLASS_I2C, busno, &bus);
        if (ret) {
                printf("GSC     : failed I2C%d probe: %d\n", busno, ret);
                return NULL;
        }
        ret = dm_i2c_probe(bus, slave, 0, &dev);
        if (ret)
                return NULL;

        return dev;
}

static int gsc_read_eeprom(int bus, int slave, int alen, struct venice_board_info *info)
{
        int i;
        int chksum;
        unsigned char *buf = (unsigned char *)info;
        struct udevice *dev;
        int ret;

        /* probe device */
        dev = gsc_get_dev(bus, slave);
        if (!dev) {
                if (slave == GSC_EEPROM_ADDR)
                        puts("ERROR: Failed to probe EEPROM\n");
                return -ENODEV;
        }

        /* read eeprom config section */
        memset(info, 0, sizeof(*info));
        ret = i2c_set_chip_offset_len(dev, alen);
        if (ret) {
                puts("EEPROM: Failed to set alen\n");
                return ret;
        }
        ret = dm_i2c_read(dev, 0x00, buf, sizeof(*info));
        if (ret) {
                if (slave == GSC_EEPROM_ADDR)
                        printf("EEPROM: Failed to read EEPROM\n");
                return ret;
        }

        /* validate checksum */
        for (chksum = 0, i = 0; i < (int)sizeof(*info) - 2; i++)
                chksum += buf[i];
        if ((info->chksum[0] != chksum >> 8) ||
            (info->chksum[1] != (chksum & 0xff))) {
                printf("EEPROM: I2C%d@0x%02x: Invalid Checksum\n", bus, slave);
                print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, sizeof(*info));
                memset(info, 0, sizeof(*info));
                return -EINVAL;
        }

        /* sanity check valid model */
        if (info->model[0] != 'G' || info->model[1] != 'W') {
                printf("EEPROM: I2C%d@0x%02x: Invalid Model in EEPROM\n", bus, slave);
                print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, sizeof(*info));
                memset(info, 0, sizeof(*info));
                return -EINVAL;
        }

        return 0;
}

static const char *gsc_get_rst_cause(struct udevice *dev)
{
        static char str[64];
        static const char * const names[] = {
                "VIN",
                "PB",
                "WDT",
                "CPU",
                "TEMP_L",
                "TEMP_R",
                "SLEEP",
                "BOOT_WDT1",
                "BOOT_WDT2",
                "SOFT_PWR",
        };
        unsigned char reg;

        /* reset cause */
        str[0] = 0;
        if (!dm_i2c_read(dev, GSC_SC_RST_CAUSE, &reg, 1)) {
                if (reg < ARRAY_SIZE(names))
                        sprintf(str, "%s", names[reg]);
                else
                        sprintf(str, "0x%02x", reg);
        }

        /* thermal protection */
        if (!dm_i2c_read(dev, GSC_SC_THERM_PROTECT, &reg, 1)) {
                strcat(str, " Thermal Protection ");
                if (reg & BIT(0))
                        strcat(str, "Enabled");
                else
                        strcat(str, "Disabled");
        }

        return str;
}

/* display hardware monitor ADC channels */
int gsc_hwmon(void)
{
        const void *fdt = gd->fdt_blob;
        struct udevice *dev;
        int node, reg, mode, len, val, offset;
        const char *label;
        u8 buf[2];
        int ret;

        node = fdt_node_offset_by_compatible(fdt, -1, "gw,gsc-adc");
        if (node <= 0)
                return node;

        /* probe device */
        dev = gsc_get_dev(GSC_BUSNO, GSC_HWMON_ADDR);
        if (!dev) {
                puts("ERROR: Failed to probe GSC HWMON\n");
                return -ENODEV;
        }

        /* iterate over hwmon nodes */
        node = fdt_first_subnode(fdt, node);
        while (node > 0) {
                reg = fdtdec_get_int(fdt, node, "reg", -1);
                mode = fdtdec_get_int(fdt, node, "gw,mode", -1);
                offset = fdtdec_get_int(fdt, node, "gw,voltage-offset-microvolt", 0);
                label = fdt_stringlist_get(fdt, node, "label", 0, NULL);

                if ((reg == -1) || (mode == -1) || !label)
                        printf("invalid dt:%s\n", fdt_get_name(fdt, node, NULL));

                memset(buf, 0, sizeof(buf));
                ret = dm_i2c_read(dev, reg, buf, sizeof(buf));
                if (ret) {
                        printf("i2c error: %d\n", ret);
                        continue;
                }
                val = buf[0] | buf[1] << 8;
                if (val >= 0) {
                        const u32 *div;
                        int r[2];

                        switch (mode) {
                        case 0: /* temperature (C*10) */
                                if (val > 0x8000)
                                        val -= 0xffff;
                                printf("%-8s: %d.%ldC\n", label, val / 10, abs(val % 10));
                                break;
                        case 1: /* prescaled voltage */
                                if (val != 0xffff)
                                        printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
                                break;
                        case 2: /* scaled based on ref volt and resolution */
                                val *= 2500;
                                val /= 1 << 12;

                                /* apply pre-scaler voltage divider */
                                div  = fdt_getprop(fdt, node, "gw,voltage-divider-ohms", &len);
                                if (div && (len == sizeof(uint32_t) * 2)) {
                                        r[0] = fdt32_to_cpu(div[0]);
                                        r[1] = fdt32_to_cpu(div[1]);
                                        if (r[0] && r[1]) {
                                                val *= (r[0] + r[1]);
                                                val /= r[1];
                                        }
                                }

                                /* adjust by offset */
                                val += (offset / 1000);

                                printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
                                break;
                        }
                }
                node = fdt_next_subnode(fdt, node);
        }

        return 0;
}

/* determine BOM revision from model */
int get_bom_rev(const char *str)
{
        int  rev_bom = 0;
        int i;

        for (i = strlen(str) - 1; i > 0; i--) {
                if (str[i] == '-')
                        break;
                if (str[i] >= '1' && str[i] <= '9') {
                        rev_bom = str[i] - '0';
                        break;
                }
        }
        return rev_bom;
}

/* determine PCB revision from model */
char get_pcb_rev(const char *str)
{
        char rev_pcb = 'A';
        int i;

        for (i = strlen(str) - 1; i > 0; i--) {
                if (str[i] == '-')
                        break;
                if (str[i] >= 'A') {
                        rev_pcb = str[i];
                        break;
                }
        }
        return rev_pcb;
}

/*
 * get dt name based on model and detail level:
 *
 * For boards that are a combination of a SoM plus a Baseboard:
 *   Venice SoM part numbers are GW70xx where xx is:
 *    7000-7019: same PCB with som dt of '0x'
 *    7020-7039: same PCB with som dt of '2x'
 *    7040-7059: same PCB with som dt of '4x'
 *    7060-7079: same PCB with som dt of '6x'
 *    7080-7099: same PCB with som dt of '8x'
 *   Venice Baseboard part numbers are GW7xxx where xxx is:
 *    7100-7199: same PCB with base dt of '71xx'
 *    7200-7299: same PCB with base dt of '72xx'
 *    7300-7399: same PCB with base dt of '73xx'
 *    7400-7499: same PCB with base dt of '74xx'
 *    7500-7599: same PCB with base dt of '75xx'
 *    7600-7699: same PCB with base dt of '76xx'
 *    7700-7799: same PCB with base dt of '77xx'
 *    7800-7899: same PCB with base dt of '78xx'
 *   DT name is comprised of:
 *    gw<base dt>-<som dt>-[base-pcb-rev][base-bom-rev][som-pcb-rev][som-bom-rev]
 *
 * For board models from 7900-7999 each PCB is unique with its own dt:
 *   DT name is comprised:
 *    gw<model>-[pcb-rev][bom-rev]
 *
 */
#define snprintfcat(dest, sz, fmt, ...) \
        snprintf((dest) + strlen(dest), (sz) - strlen(dest), fmt, ##__VA_ARGS__)
const char *gsc_get_dtb_name(int level, char *buf, int sz)
{
        const char *pre = "imx8mm-venice-gw";
        int model, rev_pcb, rev_bom;

        model = ((som_info.model[2] - '0') * 1000)
                + ((som_info.model[3] - '0') * 100)
                + ((som_info.model[4] - '0') * 10)
                + (som_info.model[5] - '0');
        rev_pcb = tolower(get_pcb_rev(som_info.model));
        rev_bom = get_bom_rev(som_info.model);

        /* som + baseboard*/
        if (base_info.model[0]) {
                /* baseboard id: 7100-7199->71; 7200-7299->72; etc */
                int base = ((base_info.model[2] - '0') * 10) + (base_info.model[3] - '0');
                /* som id: 7000-7019->1; 7020-7039->2; etc */
                int som = ((model % 100) / 20) * 2;
                int rev_base_pcb = tolower(get_pcb_rev(base_info.model));
                int rev_base_bom = get_bom_rev(base_info.model);

                snprintf(buf, sz, "%s%2dxx-%dx", pre, base, som);
                switch (level) {
                case 0: /* full model (ie gw73xx-0x-a1a1) */
                        if (rev_base_bom)
                                snprintfcat(buf, sz, "-%c%d", rev_base_pcb, rev_base_bom);
                        else
                                snprintfcat(buf, sz, "-%c", rev_base_pcb);
                        if (rev_bom)
                                snprintfcat(buf, sz, "%c%d", rev_pcb, rev_bom);
                        else
                                snprintfcat(buf, sz, "%c", rev_pcb);
                        break;
                case 1: /* don't care about SoM revision */
                        if (rev_base_bom)
                                snprintfcat(buf, sz, "-%c%d", rev_base_pcb, rev_base_bom);
                        else
                                snprintfcat(buf, sz, "-%c", rev_base_pcb);
                        snprintfcat(buf, sz, "xx");
                        break;
                case 2: /* don't care about baseboard revision */
                        snprintfcat(buf, sz, "-xx");
                        if (rev_bom)
                                snprintfcat(buf, sz, "%c%d", rev_pcb, rev_bom);
                        else
                                snprintfcat(buf, sz, "%c", rev_pcb);
                        break;
                case 3: /* don't care about SoM/baseboard revision */
                        break;
                default:
                        return NULL;
                }
        } else {
                snprintf(buf, sz, "%s%04d", pre, model);
                switch (level) {
                case 0: /* full model wth PCB and BOM revision first (ie gw7901-a1) */
                        if (rev_bom)
                                snprintfcat(buf, sz, "-%c%d", rev_pcb, rev_bom);
                        else
                                snprintfcat(buf, sz, "-%c", rev_pcb);
                        break;
                case 1: /* don't care about BOM revision */
                        snprintfcat(buf, sz, "-%c", rev_pcb);
                        break;
                case 2: /* don't care about PCB or BOM revision */
                        break;
                default:
                        return NULL;
                }
        }

        return buf;
}

static int gsc_read(void)
{
        char rev_pcb;
        int rev_bom;
        int ret;

        ret = gsc_read_eeprom(GSC_BUSNO, GSC_EEPROM_ADDR, 1, &som_info);
        if (ret) {
                memset(&som_info, 0, sizeof(som_info));
                return ret;
        }

        /* read optional baseboard EEPROM */
        gsc_read_eeprom(BASEBOARD_EEPROM_BUSNO, BASEBOARD_EEPROM_ADDR,
                        2, &base_info);

        /* create model strings */
        if (base_info.model[0]) {
                sprintf(venice_model, "GW%c%c%c%c-%c%c-",
                        som_info.model[2], /* family */
                        base_info.model[3], /* baseboard */
                        base_info.model[4], base_info.model[5], /* subload of baseboard */
                        som_info.model[4], som_info.model[5]); /* last 2digits of SOM */

                /* baseboard revision */
                rev_pcb = get_pcb_rev(base_info.model);
                rev_bom = get_bom_rev(base_info.model);
                if (rev_bom)
                        sprintf(venice_model + strlen(venice_model), "%c%d", rev_pcb, rev_bom);
                else
                        sprintf(venice_model + strlen(venice_model), "%c", rev_pcb);
                /* som revision */
                rev_pcb = get_pcb_rev(som_info.model);
                rev_bom = get_bom_rev(som_info.model);
                if (rev_bom)
                        sprintf(venice_model + strlen(venice_model), "%c%d", rev_pcb, rev_bom);
                else
                        sprintf(venice_model + strlen(venice_model), "%c", rev_pcb);
        } else {
                strcpy(venice_model, som_info.model);
        }
        venice_serial = som_info.serial;

        return 0;
}

static int gsc_info(int verbose)
{
        struct udevice *dev;
        unsigned char buf[16];

        printf("Model   : %s\n", venice_model);
        printf("Serial  : %d\n", som_info.serial);
        printf("MFGDate : %02x-%02x-%02x%02x\n",
               som_info.mfgdate[0], som_info.mfgdate[1],
               som_info.mfgdate[2], som_info.mfgdate[3]);
        if (base_info.model[0] && verbose > 1) {
                printf("SOM     : %s %d %02x-%02x-%02x%02x\n",
                       som_info.model, som_info.serial,
                       som_info.mfgdate[0], som_info.mfgdate[1],
                       som_info.mfgdate[2], som_info.mfgdate[3]);
                printf("BASE    : %s %d %02x-%02x-%02x%02x\n",
                       base_info.model, base_info.serial,
                       base_info.mfgdate[0], base_info.mfgdate[1],
                       base_info.mfgdate[2], base_info.mfgdate[3]);
        }

        /* Display RTC */
        puts("RTC     : ");
        dev = gsc_get_dev(GSC_BUSNO, GSC_RTC_ADDR);
        if (!dev) {
                puts("Failed to probe GSC RTC\n");
        } else {
                dm_i2c_read(dev, 0, buf, 6);
                printf("%d\n", buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24);
        }

        /* Display hwmon */
        gsc_hwmon();

        return 0;
}

int gsc_init(int quiet)
{
        unsigned char buf[16];
        struct udevice *dev;
        int ret;

        /*
         * On a board with a missing/depleted backup battery for GSC, the
         * board may be ready to probe the GSC before its firmware is
         * running.  We will wait here indefinately for the GSC/EEPROM.
         */
        while (1) {
                /* probe device */
                dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
                if (dev)
                        break;
                mdelay(1);
        }

        ret = dm_i2c_read(dev, 0, buf, sizeof(buf));
        if (ret) {
                puts("ERROR: Failed reading GSC\n");
                return ret;
        }
        gsc_read();

        /* banner */
        if (!quiet) {
                printf("GSC     : v%d 0x%04x", buf[GSC_SC_FWVER],
                       buf[GSC_SC_FWCRC] | buf[GSC_SC_FWCRC + 1] << 8);
                printf(" RST:%s", gsc_get_rst_cause(dev));
                printf("\n");
                gsc_info(1);
        }

        if (ret)
                hang();

        return ((16 << som_info.sdram_size) / 1024);
}

const char *gsc_get_model(void)
{
        return venice_model;
}

uint32_t gsc_get_serial(void)
{
        return venice_serial;
}

#if !(IS_ENABLED(CONFIG_SPL_BUILD))
static int gsc_sleep(unsigned long secs)
{
        unsigned char reg;
        struct udevice *dev;
        int ret;

        /* probe device */
        dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
        if (!dev)
                return -ENODEV;

        printf("GSC Sleeping for %ld seconds\n", secs);
        reg = (secs >> 24) & 0xff;
        ret = dm_i2c_write(dev, 9, &reg, 1);
        if (ret)
                goto err;
        reg = (secs >> 16) & 0xff;
        ret = dm_i2c_write(dev, 8, &reg, 1);
        if (ret)
                goto err;
        reg = (secs >> 8) & 0xff;
        ret = dm_i2c_write(dev, 7, &reg, 1);
        if (ret)
                goto err;
        reg = secs & 0xff;
        ret = dm_i2c_write(dev, 6, &reg, 1);
        if (ret)
                goto err;
        ret = dm_i2c_read(dev, GSC_SC_CTRL1, &reg, 1);
        if (ret)
                goto err;
        reg |= (1 << 2);
        ret = dm_i2c_write(dev, GSC_SC_CTRL1, &reg, 1);
        if (ret)
                goto err;
        reg &= ~(1 << 2);
        reg |= 0x3;
        ret = dm_i2c_write(dev, GSC_SC_CTRL1, &reg, 1);
        if (ret)
                goto err;

        return 0;

err:
        printf("i2c error\n");
        return ret;
}

static int gsc_boot_wd_disable(void)
{
        u8 reg;
        struct udevice *dev;
        int ret;

        /* probe device */
        dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
        if (!dev)
                return -ENODEV;

        ret = dm_i2c_read(dev, GSC_SC_CTRL1, &reg, 1);
        if (ret)
                goto err;
        reg |= (1 << GSC_SC_CTRL1_WDDIS);
        reg &= ~(1 << GSC_SC_CTRL1_BOOT_CHK);
        ret = dm_i2c_write(dev, GSC_SC_CTRL1, &reg, 1);
        if (ret)
                goto err;
        puts("GSC     : boot watchdog disabled\n");

        return 0;

err:
        printf("i2c error");
        return ret;
}

static int do_gsc(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
{
        if (argc < 2)
                return gsc_info(2);

        if (strcasecmp(argv[1], "sleep") == 0) {
                if (argc < 3)
                        return CMD_RET_USAGE;
                if (!gsc_sleep(dectoul(argv[2], NULL)))
                        return CMD_RET_SUCCESS;
        } else if (strcasecmp(argv[1], "hwmon") == 0) {
                if (!gsc_hwmon())
                        return CMD_RET_SUCCESS;
        } else if (strcasecmp(argv[1], "wd-disable") == 0) {
                if (!gsc_boot_wd_disable())
                        return CMD_RET_SUCCESS;
        }

        return CMD_RET_USAGE;
}

U_BOOT_CMD(gsc, 4, 1, do_gsc, "Gateworks System Controller",
           "[sleep <secs>]|[hwmon]|[wd-disable]\n");
#endif