// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Intel Merrifield watchdog platform device library file
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*
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* (C) Copyright 2014 Intel Corporation
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* Author: David Cohen <david.a.cohen@linux.intel.com>
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*/
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/platform_device.h>
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#include <linux/platform_data/intel-mid_wdt.h>
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#include <asm/intel-mid.h>
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#include <asm/intel_scu_ipc.h>
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#include <asm/io_apic.h>
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#include <asm/hw_irq.h>
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#define TANGIER_EXT_TIMER0_MSI 12
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static struct platform_device wdt_dev = {
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.name = "intel_mid_wdt",
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.id = -1,
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};
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static int tangier_probe(struct platform_device *pdev)
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{
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struct irq_alloc_info info;
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struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data;
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int gsi = TANGIER_EXT_TIMER0_MSI;
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int irq;
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if (!pdata)
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return -EINVAL;
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/* IOAPIC builds identity mapping between GSI and IRQ on MID */
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ioapic_set_alloc_attr(&info, cpu_to_node(0), 1, 0);
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irq = mp_map_gsi_to_irq(gsi, IOAPIC_MAP_ALLOC, &info);
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if (irq < 0) {
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dev_warn(&pdev->dev, "cannot find interrupt %d in ioapic\n", gsi);
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return irq;
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}
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pdata->irq = irq;
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return 0;
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}
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static struct intel_mid_wdt_pdata tangier_pdata = {
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.probe = tangier_probe,
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};
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static int wdt_scu_status_change(struct notifier_block *nb,
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unsigned long code, void *data)
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{
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if (code == SCU_DOWN) {
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platform_device_unregister(&wdt_dev);
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return 0;
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}
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return platform_device_register(&wdt_dev);
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}
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static struct notifier_block wdt_scu_notifier = {
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.notifier_call = wdt_scu_status_change,
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};
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static int __init register_mid_wdt(void)
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{
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if (intel_mid_identify_cpu() != INTEL_MID_CPU_CHIP_TANGIER)
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return -ENODEV;
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wdt_dev.dev.platform_data = &tangier_pdata;
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/*
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* We need to be sure that the SCU IPC is ready before watchdog device
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* can be registered:
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*/
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intel_scu_notifier_add(&wdt_scu_notifier);
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return 0;
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}
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arch_initcall(register_mid_wdt);
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