/*
 * Copyright (c) 2015 Brian Swetland
 *
 * Use of this source code is governed by a MIT-style
 * license that can be found in the LICENSE file or at
 * https://opensource.org/licenses/MIT
 */

#include <app.h>
#include <lk/err.h>
#include <lk/debug.h>
#include <string.h>
#include <stdlib.h>
#include <printf.h>
#include <dev/udc.h>

#include <platform.h>
#include <arch/arm.h>
#include <kernel/thread.h>
#include <kernel/event.h>
#include <kernel/timer.h>

#include <platform/lpc43xx-gpio.h>

#define PIN_LED     PIN(1,1)
#define GPIO_LED    GPIO(0,8)

void spifi_init(void);
void spifi_page_program(u32 addr, u32 *ptr, u32 count);
void spifi_sector_erase(u32 addr);
int spifi_verify_erased(u32 addr, u32 count);
int spifi_verify_page(u32 addr, u32 *ptr);

static event_t txevt = EVENT_INITIAL_VALUE(txevt, 0, 0);
static event_t rxevt = EVENT_INITIAL_VALUE(rxevt, 0, 0);

static udc_request_t *txreq;
static udc_request_t *rxreq;
static udc_endpoint_t *txept;
static udc_endpoint_t *rxept;

static volatile int online;
static volatile int txstatus;
static volatile int rxstatus;
static volatile unsigned rxactual;

static void lpcboot_notify(udc_gadget_t *gadget, unsigned event) {
    if (event == UDC_EVENT_ONLINE) {
        online = 1;
    } else {
        online = 0;
    }
}

static void rx_complete(udc_request_t *req, unsigned actual, int status) {
    rxactual = actual;
    rxstatus = status;
    event_signal(&rxevt, 0);
}

static void tx_complete(udc_request_t *req, unsigned actual, int status) {
    txstatus = status;
    event_signal(&txevt, 0);
}

void usb_xmit(void *data, unsigned len) {
    event_unsignal(&txevt);
    txreq->buffer = data;
    txreq->length = len;
    txstatus = 1;
    udc_request_queue(txept, txreq);
    event_wait(&txevt);
}

int usb_recv(void *data, unsigned len, lk_time_t timeout) {
    event_unsignal(&rxevt);
    rxreq->buffer = data;
    rxreq->length = len;
    rxstatus = 1;
    udc_request_queue(rxept, rxreq);
    if (event_wait_timeout(&rxevt, timeout)) {
        return ERR_TIMED_OUT;
    }
    return rxactual;
}

static udc_device_t lpcboot_device = {
    .vendor_id = 0x1209,
    .product_id = 0x5039,
    .version_id = 0x0100,
};

static udc_endpoint_t *lpcboot_endpoints[2];

static udc_gadget_t lpcboot_gadget = {
    .notify = lpcboot_notify,
    .ifc_class = 0xFF,
    .ifc_subclass = 0xFF,
    .ifc_protocol = 0xFF,
    .ifc_endpoints = 2,
    .ept = lpcboot_endpoints,
};

static void lpcboot_init(const struct app_descriptor *app) {
    udc_init(&lpcboot_device);
    lpcboot_endpoints[0] = txept = udc_endpoint_alloc(UDC_BULK_IN, 512);
    lpcboot_endpoints[1] = rxept = udc_endpoint_alloc(UDC_BULK_OUT, 512);
    txreq = udc_request_alloc();
    rxreq = udc_request_alloc();
    rxreq->complete = rx_complete;
    txreq->complete = tx_complete;
    udc_register_gadget(&lpcboot_gadget);
}

#define RAM_BASE    0x10000000
#define RAM_SIZE    (128 * 1024)

#define BOOT_BASE   0
#define BOOT_SIZE   (32 * 1024)

#define ROM_BASE    (32 * 1024)
#define ROM_SIZE    (128 * 1024)

struct device_info {
    u8 part[16];
    u8 board[16];
    u32 version;
    u32 ram_base;
    u32 ram_size;
    u32 rom_base;
    u32 rom_size;
    u32 unused0;
    u32 unused1;
    u32 unused2;
};

struct device_info DEVICE = {
    .part = "LPC43xx",
    .board = TARGET,
    .version = 0x0001000,
    .ram_base = RAM_BASE,
    .ram_size = RAM_SIZE,
    .rom_base = ROM_BASE,
    .rom_size = ROM_SIZE,
};


#define MAGIC1      0xAA113377
#define MAGIC2      0xAA773311
#define MAGIC1_ADDR 0x20003FF8
#define MAGIC2_ADDR 0x20003FFC

void boot_app(void) {
    writel(MAGIC1, MAGIC1_ADDR);
    writel(MAGIC2, MAGIC2_ADDR);
}

int erase_page(u32 addr) {
    spifi_sector_erase(addr);
    return spifi_verify_erased(addr, 0x1000/4);
}

int write_page(u32 addr, void *ptr) {
    unsigned n;
    u32 *x = ptr;
    for (n = 0; n < 16; n++) {
        spifi_page_program(addr, x, 256 / 4);
        if (spifi_verify_page(addr, x)) return -1;
        addr += 256;
        x += (256 / 4);
    }
    return 0;
}

static uint32_t ram[4096/4];

void handle(u32 magic, u32 cmd, u32 arg) {
    u32 reply[2];
    u32 addr, xfer;
    int err = 0;

    if (magic != 0xDB00A5A5)
        return;

    reply[0] = magic;
    reply[1] = -1;

    switch (cmd) {
        case 'E':
            reply[1] = erase_page(ROM_BASE);
            break;
        case 'W':
        case 'w':
            if (cmd == 'W') {
                if (arg > ROM_SIZE)
                    break;
                addr = ROM_BASE;
            } else {
                if (arg > BOOT_SIZE)
                    break;
                addr = BOOT_BASE;
            }
            reply[1] = 0;
            usb_xmit(reply, 8);
            while (arg > 0) {
                xfer = (arg > 4096) ? 4096 : arg;
                usb_recv(ram, xfer, INFINITE_TIME);
                if (!err) err = erase_page(addr);
                if (!err) err = write_page(addr, ram);
                addr += 4096;
                arg -= xfer;
            }
            printf("flash %s\n", err ? "ERROR" : "OK");
            reply[1] = err;
            break;
#if WITH_BOOT_TO_RAM
        case 'X':
            if (arg > RAM_SIZE)
                break;
            reply[1] = 0;
            usb_xmit(reply, 8);
            usb_recv(ram, arg);
            usb_xmit(reply, 8);

            /* let last txn clear */
            usb_recv_timeout(buf, 64, 10);

            boot_image(ram);
            break;
#endif
        case 'Q':
            reply[1] = 0;
            usb_xmit(reply, 8);
            usb_xmit(&DEVICE, sizeof(DEVICE));
            return;
        case 'A':
            boot_app();
        /* fallthrough */
        case 'R':
            /* reboot "normally" */
            reply[1] = 0;
            usb_xmit(reply, 8);
            udc_stop();
            platform_halt(HALT_ACTION_REBOOT, HALT_REASON_SW_RESET);
        default:
            break;
    }
    usb_xmit(reply, 8);
}

static short led_idx = 0;
static short led_delay[] = { 500, 100, 100, 100, };
static short led_state[] = {   1,   0,   1,   0, };
static timer_t led_timer = TIMER_INITIAL_VALUE(led_timer);

static enum handler_return led_timer_cb(timer_t *timer, lk_time_t now, void *arg) {
    gpio_set(GPIO_LED, led_state[led_idx]);
    timer_set_oneshot(timer, led_delay[led_idx], led_timer_cb, NULL);
    led_idx++;
    if (led_idx == (sizeof(led_state)/sizeof(led_state[0]))) {
        led_idx = 0;
    }
    return 0;
}

static void lpcboot_entry(const struct app_descriptor *app, void *args) {
    lk_time_t timeout;
    int r;
    u32 buf[64/4];

#if 0
    timeout = INFINITE_TIME;
#else
    if (readl(32768) != 0) {
        timeout = 3000;
    } else {
        timeout = INFINITE_TIME;
    }
#endif

    pin_config(PIN_LED, PIN_MODE(0) | PIN_PLAIN);
    gpio_config(GPIO_LED, GPIO_OUTPUT);
    led_timer_cb(&led_timer, 0, NULL);

    udc_start();
    spifi_init();
    for (;;) {
        if (!online) {
            thread_yield();
            continue;
        }
        r = usb_recv(buf, 64, timeout);
        if (r == ERR_TIMED_OUT) {
            boot_app();
            platform_halt(HALT_ACTION_REBOOT, HALT_REASON_SW_RESET);
        }
        if (r == 12) {
            handle(buf[0], buf[1], buf[2]);
            timeout = INFINITE_TIME;
        }
    }
}

APP_START(usbtest)
.init = lpcboot_init,
.entry = lpcboot_entry,
APP_END