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>
diff --git a/arch/arm/mach-imx/system.c b/arch/arm/mach-imx/system.c
index 695e0d7..02cf449 100644
--- a/arch/arm/mach-imx/system.c
+++ b/arch/arm/mach-imx/system.c
@@ -30,6 +30,7 @@
#include "hardware.h"
static void __iomem *wdog_base;
+static struct clk *wdog_clk;
/*
* Reset the system. It is called by machine_restart().
@@ -38,16 +39,13 @@
{
unsigned int wcr_enable;
- if (cpu_is_mx1()) {
- wcr_enable = (1 << 0);
- } else {
- struct clk *clk;
+ if (wdog_clk)
+ clk_enable(wdog_clk);
- clk = clk_get_sys("imx2-wdt.0", NULL);
- if (!IS_ERR(clk))
- clk_prepare_enable(clk);
+ if (cpu_is_mx1())
+ wcr_enable = (1 << 0);
+ else
wcr_enable = (1 << 2);
- }
/* Assert SRS signal */
__raw_writew(wcr_enable, wdog_base);
@@ -55,7 +53,7 @@
/* wait for reset to assert... */
mdelay(500);
- printk(KERN_ERR "Watchdog reset failed to assert reset\n");
+ pr_err("%s: Watchdog reset failed to assert reset\n", __func__);
/* delay to allow the serial port to show the message */
mdelay(50);
@@ -64,7 +62,16 @@
soft_restart(0);
}
-void mxc_arch_reset_init(void __iomem *base)
+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);
}