// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Freescale Semiconductor, Inc.
 */

#include <linux/context_tracking.h>
#include <linux/cpuidle.h>
#include <linux/module.h>
#include <asm/cpuidle.h>

#include <soc/imx/cpuidle.h>

#include "common.h"
#include "cpuidle.h"
#include "hardware.h"

static int num_idle_cpus = 0;
static DEFINE_RAW_SPINLOCK(cpuidle_lock);

static __cpuidle int imx6q_enter_wait(struct cpuidle_device *dev,
                                      struct cpuidle_driver *drv, int index)
{
        raw_spin_lock(&cpuidle_lock);
        if (++num_idle_cpus == num_online_cpus())
                imx6_set_lpm(WAIT_UNCLOCKED);
        raw_spin_unlock(&cpuidle_lock);

        ct_cpuidle_enter();
        cpu_do_idle();
        ct_cpuidle_exit();

        raw_spin_lock(&cpuidle_lock);
        if (num_idle_cpus-- == num_online_cpus())
                imx6_set_lpm(WAIT_CLOCKED);
        raw_spin_unlock(&cpuidle_lock);

        return index;
}

static struct cpuidle_driver imx6q_cpuidle_driver = {
        .name = "imx6q_cpuidle",
        .owner = THIS_MODULE,
        .states = {
                /* WFI */
                ARM_CPUIDLE_WFI_STATE,
                /* WAIT */
                {
                        .exit_latency = 50,
                        .target_residency = 75,
                        .flags = CPUIDLE_FLAG_TIMER_STOP | CPUIDLE_FLAG_RCU_IDLE,
                        .enter = imx6q_enter_wait,
                        .name = "WAIT",
                        .desc = "Clock off",
                },
        },
        .state_count = 2,
        .safe_state_index = 0,
};

/*
 * i.MX6 Q/DL has an erratum (ERR006687) that prevents the FEC from waking the
 * CPUs when they are in wait(unclocked) state. As the hardware workaround isn't
 * applicable to all boards, disable the deeper idle state when the workaround
 * isn't present and the FEC is in use.
 */
void imx6q_cpuidle_fec_irqs_used(void)
{
        cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, true);
}
EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_used);

void imx6q_cpuidle_fec_irqs_unused(void)
{
        cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, false);
}
EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_unused);

int __init imx6q_cpuidle_init(void)
{
        /* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */
        imx6_set_int_mem_clk_lpm(true);

        return cpuidle_register(&imx6q_cpuidle_driver, NULL);
}