// SPDX-License-Identifier: GPL-2.0-only
/*
 * intel_soc_dts_thermal.c
 * Copyright (c) 2014, Intel Corporation.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
#include "intel_soc_dts_iosf.h"

#define CRITICAL_OFFSET_FROM_TJ_MAX     5000

static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
module_param(crit_offset, int, 0644);
MODULE_PARM_DESC(crit_offset,
        "Critical Temperature offset from tj max in millidegree Celsius.");

/* IRQ 86 is a fixed APIC interrupt for BYT DTS Aux threshold notifications */
#define BYT_SOC_DTS_APIC_IRQ    86

static int soc_dts_thres_gsi;
static int soc_dts_thres_irq;
static struct intel_soc_dts_sensors *soc_dts;

static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
{
        pr_debug("proc_thermal_interrupt\n");
        intel_soc_dts_iosf_interrupt_handler(soc_dts);

        return IRQ_HANDLED;
}

static const struct x86_cpu_id soc_thermal_ids[] = {
        X86_MATCH_VFM(INTEL_ATOM_SILVERMONT, BYT_SOC_DTS_APIC_IRQ),
        {}
};
MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);

static int __init intel_soc_thermal_init(void)
{
        int err = 0;
        const struct x86_cpu_id *match_cpu;

        match_cpu = x86_match_cpu(soc_thermal_ids);
        if (!match_cpu)
                return -ENODEV;

        /* Create a zone with 2 trips with marked as read only */
        soc_dts = intel_soc_dts_iosf_init(INTEL_SOC_DTS_INTERRUPT_APIC, true,
                                          crit_offset);
        if (IS_ERR(soc_dts)) {
                err = PTR_ERR(soc_dts);
                return err;
        }

        soc_dts_thres_gsi = (int)match_cpu->driver_data;
        if (soc_dts_thres_gsi) {
                /*
                 * Note the flags here MUST match the firmware defaults, rather
                 * then the request_irq flags, otherwise we get an EBUSY error.
                 */
                soc_dts_thres_irq = acpi_register_gsi(NULL, soc_dts_thres_gsi,
                                                      ACPI_LEVEL_SENSITIVE,
                                                      ACPI_ACTIVE_LOW);
                if (soc_dts_thres_irq < 0) {
                        pr_warn("intel_soc_dts: Could not get IRQ for GSI %d, err %d\n",
                                soc_dts_thres_gsi, soc_dts_thres_irq);
                        soc_dts_thres_irq = 0;
                }
        }

        if (soc_dts_thres_irq) {
                err = request_threaded_irq(soc_dts_thres_irq, NULL,
                                           soc_irq_thread_fn,
                                           IRQF_TRIGGER_RISING | IRQF_ONESHOT,
                                           "soc_dts", soc_dts);
                if (err) {
                        /*
                         * Do not just error out because the user space thermal
                         * daemon such as DPTF may use polling instead of being
                         * interrupt driven.
                         */
                        pr_warn("request_threaded_irq ret %d\n", err);
                }
        }

        return 0;
}

static void __exit intel_soc_thermal_exit(void)
{
        if (soc_dts_thres_irq) {
                free_irq(soc_dts_thres_irq, soc_dts);
                acpi_unregister_gsi(soc_dts_thres_gsi);
        }
        intel_soc_dts_iosf_exit(soc_dts);
}

module_init(intel_soc_thermal_init)
module_exit(intel_soc_thermal_exit)

MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");