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1// SPDX-License-Identifier: GPL-2.0-only2// Copyright (C) 2016 Broadcom3 4#include <linux/io.h>5#include <linux/mod_devicetable.h>6#include <linux/platform_device.h>7#include <linux/reboot.h>8 9#define RSTMGR_REG_WR_ACCESS_OFFSET 010#define RSTMGR_REG_CHIP_SOFT_RST_OFFSET 411 12#define RSTMGR_WR_PASSWORD 0xa5a513#define RSTMGR_WR_PASSWORD_SHIFT 814#define RSTMGR_WR_ACCESS_ENABLE 115 16static void __iomem *kona_reset_base;17 18static int kona_reset_handler(struct sys_off_data *data)19{20 /*21 * A soft reset is triggered by writing a 0 to bit 0 of the soft reset22 * register. To write to that register we must first write the password23 * and the enable bit in the write access enable register.24 */25 writel((RSTMGR_WR_PASSWORD << RSTMGR_WR_PASSWORD_SHIFT) |26 RSTMGR_WR_ACCESS_ENABLE,27 kona_reset_base + RSTMGR_REG_WR_ACCESS_OFFSET);28 writel(0, kona_reset_base + RSTMGR_REG_CHIP_SOFT_RST_OFFSET);29 30 return NOTIFY_DONE;31}32 33static int kona_reset_probe(struct platform_device *pdev)34{35 kona_reset_base = devm_platform_ioremap_resource(pdev, 0);36 if (IS_ERR(kona_reset_base))37 return PTR_ERR(kona_reset_base);38 39 return devm_register_sys_off_handler(&pdev->dev, SYS_OFF_MODE_RESTART,40 128, kona_reset_handler, NULL);41}42 43static const struct of_device_id of_match[] = {44 { .compatible = "brcm,bcm21664-resetmgr" },45 {},46};47 48static struct platform_driver bcm_kona_reset_driver = {49 .probe = kona_reset_probe,50 .driver = {51 .name = "brcm-kona-reset",52 .of_match_table = of_match,53 },54};55 56builtin_platform_driver(bcm_kona_reset_driver);57