On Mon, Jun 08, 2015 at 03:11:35PM +0800, Caesar Wang wrote: > diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c > index bd40852..5bc2a89 100644 > --- a/arch/arm/mach-rockchip/platsmp.c > +++ b/arch/arm/mach-rockchip/platsmp.c > @@ -321,6 +321,9 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus) > #ifdef CONFIG_HOTPLUG_CPU > static int rockchip_cpu_kill(unsigned int cpu) > { > + /* ensure CPU can enter the WFI/WFE state */ I would like to see a better comment here, describing what the problem is. Maybe something like this: /* * We need a delay here to ensure that the dying CPU can finish * executing v7_coherency_exit() and reach the WFI/WFE state * prior to having the power domain disabled. */ Thanks. > + mdelay(1); > + > pmu_set_power_domain(0 + cpu, false); > return 1; > } > -- > 1.9.1 > -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net.