// SPDX-License-Identifier: GPL-2.0
//
// Copyright 2008 Openmoko, Inc.
// Copyright 2008 Simtec Electronics
//      Ben Dooks <ben@simtec.co.uk>
//      http://armlinux.simtec.co.uk/
//
// S3C64XX - Interrupt handling Power Management

/*
 * NOTE: Code in this file is not used when booting with Device Tree support.
 */

#include <linux/kernel.h>
#include <linux/syscore_ops.h>
#include <linux/interrupt.h>
#include <linux/serial_core.h>
#include <linux/serial_s3c.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/of.h>

#include "map.h"

#include "regs-gpio.h"
#include "cpu.h"
#include "pm.h"

/* We handled all the IRQ types in this code, to save having to make several
 * small files to handle each different type separately. Having the EINT_GRP
 * code here shouldn't be as much bloat as the IRQ table space needed when
 * they are enabled. The added benefit is we ensure that these registers are
 * in the same state as we suspended.
 */

static struct sleep_save irq_save[] = {
        SAVE_ITEM(S3C64XX_PRIORITY),
        SAVE_ITEM(S3C64XX_EINT0CON0),
        SAVE_ITEM(S3C64XX_EINT0CON1),
        SAVE_ITEM(S3C64XX_EINT0FLTCON0),
        SAVE_ITEM(S3C64XX_EINT0FLTCON1),
        SAVE_ITEM(S3C64XX_EINT0FLTCON2),
        SAVE_ITEM(S3C64XX_EINT0FLTCON3),
        SAVE_ITEM(S3C64XX_EINT0MASK),
};

static struct irq_grp_save {
        u32     fltcon;
        u32     con;
        u32     mask;
} eint_grp_save[5];

#ifndef CONFIG_SERIAL_SAMSUNG_UARTS
#define SERIAL_SAMSUNG_UARTS 0
#else
#define SERIAL_SAMSUNG_UARTS CONFIG_SERIAL_SAMSUNG_UARTS
#endif

static u32 irq_uart_mask[SERIAL_SAMSUNG_UARTS];

static int s3c64xx_irq_pm_suspend(void *data)
{
        struct irq_grp_save *grp = eint_grp_save;
        int i;

        S3C_PMDBG("%s: suspending IRQs\n", __func__);

        s3c_pm_do_save(irq_save, ARRAY_SIZE(irq_save));

        for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
                irq_uart_mask[i] = __raw_readl(S3C_VA_UARTx(i) + S3C64XX_UINTM);

        for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
                grp->con = __raw_readl(S3C64XX_EINT12CON + (i * 4));
                grp->mask = __raw_readl(S3C64XX_EINT12MASK + (i * 4));
                grp->fltcon = __raw_readl(S3C64XX_EINT12FLTCON + (i * 4));
        }

        return 0;
}

static void s3c64xx_irq_pm_resume(void *data)
{
        struct irq_grp_save *grp = eint_grp_save;
        int i;

        S3C_PMDBG("%s: resuming IRQs\n", __func__);

        s3c_pm_do_restore(irq_save, ARRAY_SIZE(irq_save));

        for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
                __raw_writel(irq_uart_mask[i], S3C_VA_UARTx(i) + S3C64XX_UINTM);

        for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
                __raw_writel(grp->con, S3C64XX_EINT12CON + (i * 4));
                __raw_writel(grp->mask, S3C64XX_EINT12MASK + (i * 4));
                __raw_writel(grp->fltcon, S3C64XX_EINT12FLTCON + (i * 4));
        }

        S3C_PMDBG("%s: IRQ configuration restored\n", __func__);
}

static const struct syscore_ops s3c64xx_irq_syscore_ops = {
        .suspend = s3c64xx_irq_pm_suspend,
        .resume  = s3c64xx_irq_pm_resume,
};

static struct syscore s3c64xx_irq_syscore = {
        .ops = &s3c64xx_irq_syscore_ops,
};

static __init int s3c64xx_syscore_init(void)
{
        /* Appropriate drivers (pinctrl, uart) handle this when using DT. */
        if (of_have_populated_dt() || !soc_is_s3c64xx())
                return 0;

        register_syscore(&s3c64xx_irq_syscore);

        return 0;
}

core_initcall(s3c64xx_syscore_init);