Files
linux_media/arch/arm/mach-imx/system.c
Shawn Guo 18cb680f1a ARM: imx: move clk_prepare() out from mxc_restart()
It's inappropriate to call clk_prepare() in mxc_restart(), because the
restart routine could be called in atomic context.  Move clk_get() and
clk_prepare() into mxc_arch_reset_init() and only have the atomic part
clk_enable() be called in mxc_restart().

As a result, mxc_arch_reset_init() needs to be called after clk gets
initialized.

While there, it also changes printk(KERN_ERR ...) to pr_err() and adds
__init annotation for mxc_arch_reset_init().

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2013-06-17 15:45:10 +08:00

78 lines
1.9 KiB
C

/*
* Copyright (C) 1999 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd
* Copyright 2006-2007 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright 2008 Juergen Beisert, kernel@pengutronix.de
* Copyright 2009 Ilya Yanok, Emcraft Systems Ltd, yanok@emcraft.com
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <asm/system_misc.h>
#include <asm/proc-fns.h>
#include <asm/mach-types.h>
#include "common.h"
#include "hardware.h"
static void __iomem *wdog_base;
static struct clk *wdog_clk;
/*
* Reset the system. It is called by machine_restart().
*/
void mxc_restart(char mode, const char *cmd)
{
unsigned int wcr_enable;
if (wdog_clk)
clk_enable(wdog_clk);
if (cpu_is_mx1())
wcr_enable = (1 << 0);
else
wcr_enable = (1 << 2);
/* Assert SRS signal */
__raw_writew(wcr_enable, wdog_base);
/* wait for reset to assert... */
mdelay(500);
pr_err("%s: Watchdog reset failed to assert reset\n", __func__);
/* delay to allow the serial port to show the message */
mdelay(50);
/* we'll take a jump through zero as a poor second */
soft_restart(0);
}
void __init mxc_arch_reset_init(void __iomem *base)
{
wdog_base = base;
wdog_clk = clk_get_sys("imx2-wdt.0", NULL);
if (IS_ERR(wdog_clk)) {
pr_warn("%s: failed to get wdog clock\n", __func__);
wdog_clk = NULL;
return;
}
clk_prepare(wdog_clk);
}