// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
 * Author: Fuxin Zhang, zhangfx@lemote.com
 * Copyright (C) 2009 Lemote, Inc.
 * Author: Zhangjin Wu, wuzhangjin@gmail.com
 */
#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/kexec.h>
#include <linux/pm.h>
#include <linux/reboot.h>
#include <linux/slab.h>

#include <asm/bootinfo.h>
#include <asm/idle.h>
#include <asm/reboot.h>
#include <asm/bug.h>

#include <loongson.h>
#include <boot_param.h>

static int firmware_restart(struct sys_off_data *unusedd)
{

        void (*fw_restart)(void) = (void *)loongson_sysconf.restart_addr;

        fw_restart();
        return NOTIFY_DONE;
}

static int firmware_poweroff(struct sys_off_data *unused)
{
        void (*fw_poweroff)(void) = (void *)loongson_sysconf.poweroff_addr;

        fw_poweroff();
        return NOTIFY_DONE;
}

#ifdef CONFIG_KEXEC_CORE

/* 0X80000000~0X80200000 is safe */
#define MAX_ARGS        64
#define KEXEC_CTRL_CODE 0xFFFFFFFF80100000UL
#define KEXEC_ARGV_ADDR 0xFFFFFFFF80108000UL
#define KEXEC_ARGV_SIZE COMMAND_LINE_SIZE
#define KEXEC_ENVP_SIZE 4800

static int kexec_argc;
static int kdump_argc;
static void *kexec_argv;
static void *kdump_argv;
static void *kexec_envp;

static int loongson_kexec_prepare(struct kimage *image)
{
        int i, argc = 0;
        unsigned int *argv;
        char *str, *ptr, *bootloader = "kexec";

        /* argv at offset 0, argv[] at offset KEXEC_ARGV_SIZE/2 */
        if (image->type == KEXEC_TYPE_DEFAULT)
                argv = (unsigned int *)kexec_argv;
        else
                argv = (unsigned int *)kdump_argv;

        argv[argc++] = (unsigned int)(KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2);

        for (i = 0; i < image->nr_segments; i++) {
                if (!strncmp(bootloader, (char *)image->segment[i].buf,
                                strlen(bootloader))) {
                        /*
                         * convert command line string to array
                         * of parameters (as bootloader does).
                         */
                        int offt;
                        str = (char *)argv + KEXEC_ARGV_SIZE/2;
                        memcpy(str, image->segment[i].buf, KEXEC_ARGV_SIZE/2);
                        ptr = strchr(str, ' ');

                        while (ptr && (argc < MAX_ARGS)) {
                                *ptr = '\0';
                                if (ptr[1] != ' ') {
                                        offt = (int)(ptr - str + 1);
                                        argv[argc] = KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2 + offt;
                                        argc++;
                                }
                                ptr = strchr(ptr + 1, ' ');
                        }
                        break;
                }
        }

        if (image->type == KEXEC_TYPE_DEFAULT)
                kexec_argc = argc;
        else
                kdump_argc = argc;

        /* kexec/kdump need a safe page to save reboot_code_buffer */
        image->control_code_page = virt_to_page((void *)KEXEC_CTRL_CODE);

        return 0;
}

static void loongson_kexec_shutdown(void)
{
#ifdef CONFIG_SMP
        int cpu;

        /* All CPUs go to reboot_code_buffer */
        for_each_possible_cpu(cpu)
                if (!cpu_online(cpu))
                        cpu_device_up(get_cpu_device(cpu));

        secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
#endif
        kexec_args[0] = kexec_argc;
        kexec_args[1] = fw_arg1;
        kexec_args[2] = fw_arg2;
        memcpy((void *)fw_arg1, kexec_argv, KEXEC_ARGV_SIZE);
        memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
}

static void loongson_crash_shutdown(struct pt_regs *regs)
{
        default_machine_crash_shutdown(regs);
        kexec_args[0] = kdump_argc;
        kexec_args[1] = fw_arg1;
        kexec_args[2] = fw_arg2;
#ifdef CONFIG_SMP
        secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
#endif
        memcpy((void *)fw_arg1, kdump_argv, KEXEC_ARGV_SIZE);
        memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
}

#endif

static int __init mips_reboot_setup(void)
{
        if (loongson_sysconf.restart_addr) {
                register_sys_off_handler(SYS_OFF_MODE_RESTART,
                                 SYS_OFF_PRIO_FIRMWARE,
                                 firmware_restart, NULL);
        }

        if (loongson_sysconf.poweroff_addr) {
                register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
                                 SYS_OFF_PRIO_FIRMWARE,
                                 firmware_poweroff, NULL);
        }

#ifdef CONFIG_KEXEC_CORE
        kexec_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
        if (WARN_ON(!kexec_argv))
                return -ENOMEM;

        kdump_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
        if (WARN_ON(!kdump_argv))
                return -ENOMEM;

        kexec_envp = kmalloc(KEXEC_ENVP_SIZE, GFP_KERNEL);
        if (WARN_ON(!kexec_envp))
                return -ENOMEM;

        fw_arg1 = KEXEC_ARGV_ADDR;
        memcpy(kexec_envp, (void *)fw_arg2, KEXEC_ENVP_SIZE);

        _machine_kexec_prepare = loongson_kexec_prepare;
        _machine_kexec_shutdown = loongson_kexec_shutdown;
        _machine_crash_shutdown = loongson_crash_shutdown;
#endif

        return 0;
}

arch_initcall(mips_reboot_setup);