// SPDX-License-Identifier: GPL-2.0
/*
 *  Copyright (C) 2021, Qing Zhang <zhangqing@loongson.cn>
 *  Loongson-2K1000 reset support
 */

#include <linux/of_address.h>
#include <linux/pm.h>
#include <asm/reboot.h>

#define PM1_STS         0x0c /* Power Management 1 Status Register */
#define PM1_CNT         0x14 /* Power Management 1 Control Register */
#define RST_CNT         0x30 /* Reset Control Register */

static void __iomem *base;

static void ls2k_restart(char *command)
{
        writel(0x1, base + RST_CNT);
}

static void ls2k_poweroff(void)
{
        /* Clear */
        writel((readl(base + PM1_STS) & 0xffffffff), base + PM1_STS);
        /* Sleep Enable | Soft Off*/
        writel(GENMASK(12, 10) | BIT(13), base + PM1_CNT);
}

static int ls2k_reset_init(void)
{
        struct device_node *np;

        np = of_find_compatible_node(NULL, NULL, "loongson,ls2k-pm");
        if (!np) {
                pr_info("Failed to get PM node\n");
                return -ENODEV;
        }

        base = of_iomap(np, 0);
        of_node_put(np);
        if (!base) {
                pr_info("Failed to map PM register base address\n");
                return -ENOMEM;
        }

        _machine_restart = ls2k_restart;
        pm_power_off = ls2k_poweroff;

        return 0;
}

arch_initcall(ls2k_reset_init);