diff options
author | Caesar Wang <wxt@rock-chips.com> | 2015-06-09 17:49:58 +0800 |
---|---|---|
committer | Heiko Stuebner <heiko@sntech.de> | 2015-07-06 00:46:59 +0200 |
commit | e306bc16c53199e7440e1fee69dd91dc0a56edee (patch) | |
tree | f918e432d41d2b19e4aa2b096aeb900132ca6a4c | |
parent | fe4407c0dc58215a7abfb7532740d79ddabe7a7a (diff) | |
download | op-kernel-dev-e306bc16c53199e7440e1fee69dd91dc0a56edee.zip op-kernel-dev-e306bc16c53199e7440e1fee69dd91dc0a56edee.tar.gz |
ARM: rockchip: ensure CPU to enter WFI/WFE state
The patch can ensure that v7_exit_coherency_flush() in rockchip_cpu_die()
executed in time.
The mdelay(1) has enough time to fix the problem of CPU offlining.
That's a workaround way in rockchip hotplug code,
At least, we haven't a better way to solve it. Who know,
that maybe fixed by chip (hardware) in the future.
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
-rw-r--r-- | arch/arm/mach-rockchip/platsmp.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c index d1a5fec..4187ac2 100644 --- a/arch/arm/mach-rockchip/platsmp.c +++ b/arch/arm/mach-rockchip/platsmp.c @@ -321,6 +321,13 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus) #ifdef CONFIG_HOTPLUG_CPU static int rockchip_cpu_kill(unsigned int cpu) { + /* + * 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. + */ + mdelay(1); + pmu_set_power_domain(0 + cpu, false); return 1; } |