Re: [PATCH 2/3] ARM: rockchip: ensure CPU to enter WIF state

Kever Yang
2015-06-05T06:33:00Z

Hi Caesar,

Subject typo WIF/WFI.

On 06/05/2015 12:47 PM, Caesar Wang wrote:
> In idle mode, core1/2/3 of Cortex-A17 should be either power off or in
> WFI/WFE state.
> we can delay 1ms to ensure the CPU enter WFI state.
>
> Signed-off-by: Caesar Wang <wxt@rock-chips.com>
> ---
>
> arch/arm/mach-rockchip/platsmp.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
> index 1230d3d..978c357 100644
> --- a/arch/arm/mach-rockchip/platsmp.c
> +++ b/arch/arm/mach-rockchip/platsmp.c
> @@ -316,6 +316,9 @@ 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 */
> + mdelay(1);
> +
Does it matter if core is not in WFI state when we want to power down it?

Thanks,
- Kever
> pmu_set_power_domain(0 + cpu, false);
> return 1;
> }