arch/arm/mach-msm/restart.c

/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/reboot.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/mfd/pmic8058.h>
#include <linux/mfd/pmic8901.h>
#include <linux/mfd/pm8xxx/misc.h>

#include <asm/mach-types.h>

#include <mach/msm_iomap.h>
#include <mach/restart.h>
#include <mach/scm-io.h>
#include <mach/socinfo.h>

#define TCSR_WDT_CFG 0x30

#define WDT0_RST       (MSM_TMR0_BASE + 0x38)
#define WDT0_EN        (MSM_TMR0_BASE + 0x40)
#define WDT0_BARK_TIME (MSM_TMR0_BASE + 0x4C)
#define WDT0_BITE_TIME (MSM_TMR0_BASE + 0x5C)

#define PSHOLD_CTL_SU (MSM_TLMM_BASE + 0x820)

#define RESTART_REASON_ADDR 0x65C
#define DLOAD_MODE_ADDR     0x0

static int restart_mode;
void *restart_reason;

#ifdef CONFIG_MSM_DLOAD_MODE
static int in_panic;
static void *dload_mode_addr;

/* Download mode master kill-switch */
static int dload_set(const char *val, struct kernel_param *kp);
static int download_mode = 1;
module_param_call(download_mode, dload_set, param_get_int,
			&download_mode, 0644);

static int panic_prep_restart(struct notifier_block *this,
			      unsigned long event, void *ptr)
{
	in_panic = 1;
	return NOTIFY_DONE;
}

static struct notifier_block panic_blk = {
	.notifier_call	= panic_prep_restart,
};

static void set_dload_mode(int on)
{
	if (dload_mode_addr) {
		__raw_writel(on ? 0xE47B337D : 0, dload_mode_addr);
		__raw_writel(on ? 0xCE14091A : 0,
		       dload_mode_addr + sizeof(unsigned int));
		mb();
	}
}

static int dload_set(const char *val, struct kernel_param *kp)
{
	int ret;
	int old_val = download_mode;

	ret = param_set_int(val, kp);

	if (ret)
		return ret;

	/* If download_mode is not zero or one, ignore. */
	if (download_mode >> 1) {
		download_mode = old_val;
		return -EINVAL;
	}

	set_dload_mode(download_mode);

	return 0;
}
#else
#define set_dload_mode(x) do {} while (0)
#endif

void msm_set_restart_mode(int mode)
{
	restart_mode = mode;
}
EXPORT_SYMBOL(msm_set_restart_mode);

static void msm_power_off(void)
{
	printk(KERN_NOTICE "Powering off the SoC\n");
#ifdef CONFIG_MSM_DLOAD_MODE
	set_dload_mode(0);
#endif
	if (cpu_is_msm8x60()) {
		pm8058_reset_pwr_off(0);
		pm8901_reset_pwr_off(0);
	}
	pm8xxx_reset_pwr_off(0);
	__raw_writel(0, PSHOLD_CTL_SU);
	mdelay(10000);
	printk(KERN_ERR "Powering off has failed\n");
	return;
}

void arch_reset(char mode, const char *cmd)
{

#ifdef CONFIG_MSM_DLOAD_MODE

	/* This looks like a normal reboot at this point. */
	set_dload_mode(0);

	/* Write download mode flags if we're panic'ing */
	set_dload_mode(in_panic);

	/* Write download mode flags if restart_mode says so */
	if (restart_mode == RESTART_DLOAD)
		set_dload_mode(1);

	/* Kill download mode if master-kill switch is set */
	if (!download_mode)
		set_dload_mode(0);
#endif

	printk(KERN_NOTICE "Going down for restart now\n");

	if (cpu_is_msm8x60())
		pm8058_reset_pwr_off(1);
	pm8xxx_reset_pwr_off(1);

	if (cmd != NULL) {
		if (!strncmp(cmd, "bootloader", 10)) {
			__raw_writel(0x77665500, restart_reason);
		} else if (!strncmp(cmd, "recovery", 8)) {
			__raw_writel(0x77665502, restart_reason);
		} else if (!strncmp(cmd, "oem-", 4)) {
			unsigned long code;
			code = simple_strtoul(cmd + 4, NULL, 16) & 0xff;
			__raw_writel(0x6f656d00 | code, restart_reason);
		} else {
			__raw_writel(0x77665501, restart_reason);
		}
	}

	__raw_writel(0, WDT0_EN);
	if (!(machine_is_msm8x60_fusion() || machine_is_msm8x60_fusn_ffa())) {
		mb();
		__raw_writel(0, PSHOLD_CTL_SU); /* Actually reset the chip */
		mdelay(5000);
		pr_notice("PS_HOLD didn't work, falling back to watchdog\n");
	}

	__raw_writel(1, WDT0_RST);
	__raw_writel(5*0x31F3, WDT0_BARK_TIME);
	__raw_writel(0x31F3, WDT0_BITE_TIME);
	__raw_writel(1, WDT0_EN);
	secure_writel(3, MSM_TCSR_BASE + TCSR_WDT_CFG);

	mdelay(10000);
	printk(KERN_ERR "Restarting has failed\n");
}

static int __init msm_restart_init(void)
{
#ifdef CONFIG_MSM_DLOAD_MODE
	atomic_notifier_chain_register(&panic_notifier_list, &panic_blk);
	dload_mode_addr = MSM_IMEM_BASE + DLOAD_MODE_ADDR;

	/* Reset detection is switched on below.*/
	set_dload_mode(1);
#endif
	restart_reason = MSM_IMEM_BASE + RESTART_REASON_ADDR;
	pm_power_off = msm_power_off;

	return 0;
}

late_initcall(msm_restart_init);