linux-imx

/*

 * Copyright (C) 2016 Broadcom

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation version 2.

 *

 * This program is distributed "as is" WITHOUT ANY WARRANTY of any

 * kind, whether express or implied; without even the implied warranty

 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

​

#include <linux/io.h>

#include <linux/of_address.h>

#include <linux/of_platform.h>

#include <linux/reboot.h>

​

#define RSTMGR_REG_WR_ACCESS_OFFSET 0

#define RSTMGR_REG_CHIP_SOFT_RST_OFFSET 4

​

#define RSTMGR_WR_PASSWORD      0xa5a5

#define RSTMGR_WR_PASSWORD_SHIFT    8

#define RSTMGR_WR_ACCESS_ENABLE     1

​

static void __iomem *kona_reset_base;

​

static int kona_reset_handler(struct notifier_block *this,

                unsigned long mode, void *cmd)

{

    /*

     * A soft reset is triggered by writing a 0 to bit 0 of the soft reset

     * register. To write to that register we must first write the password

     * and the enable bit in the write access enable register.

     */

    writel((RSTMGR_WR_PASSWORD << RSTMGR_WR_PASSWORD_SHIFT) |

        RSTMGR_WR_ACCESS_ENABLE,

        kona_reset_base + RSTMGR_REG_WR_ACCESS_OFFSET);

    writel(0, kona_reset_base + RSTMGR_REG_CHIP_SOFT_RST_OFFSET);

​

    return NOTIFY_DONE;

}

​

static struct notifier_block kona_reset_nb = {

    .notifier_call = kona_reset_handler,

    .priority = 128,

};

​

static int kona_reset_probe(struct platform_device *pdev)

{

    struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

​

    kona_reset_base = devm_ioremap_resource(&pdev->dev, res);

    if (IS_ERR(kona_reset_base))

        return PTR_ERR(kona_reset_base);

​

    return register_restart_handler(&kona_reset_nb);

}

​

static const struct of_device_id of_match[] = {

    { .compatible = "brcm,bcm21664-resetmgr" },

    {},

};