ARM: imx: disable cpu in .cpu_kill hook

It's buggy to disable the cpu that is being hot-unplugged in .cpu_die
hook which runs on the cpu itself.  Instead, it should be done in
.cpu_kill which runs on the thread (another cpu) that asks for shutting
down the cpu.  Move imx_enable_cpu(cpu, false) call into .cpu_kill
hook, and leave the cpu to be hot-unplugged in WFI within .cpu_die,
so that we can get a more stable cpu hot-plug operation.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
This commit is contained in:
Shawn Guo 2013-01-14 14:08:50 +08:00
parent afc10301f7
commit 8375766421
3 changed files with 9 additions and 5 deletions

View File

@ -142,6 +142,7 @@ extern int imx6q_set_lpm(enum mxc_cpu_pwr_mode mode);
extern void imx6q_clock_map_io(void);
extern void imx_cpu_die(unsigned int cpu);
extern int imx_cpu_kill(unsigned int cpu);
#ifdef CONFIG_PM
extern void imx6q_pm_init(void);

View File

@ -46,9 +46,11 @@ static inline void cpu_enter_lowpower(void)
void imx_cpu_die(unsigned int cpu)
{
cpu_enter_lowpower();
imx_enable_cpu(cpu, false);
/* spin here until hardware takes it down */
while (1)
;
cpu_do_idle();
}
int imx_cpu_kill(unsigned int cpu)
{
imx_enable_cpu(cpu, false);
return 1;
}

View File

@ -92,5 +92,6 @@ struct smp_operations imx_smp_ops __initdata = {
.smp_boot_secondary = imx_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = imx_cpu_die,
.cpu_kill = imx_cpu_kill,
#endif
};