From mboxrd@z Thu Jan 1 00:00:00 1970 From: wxt@rock-chips.com (Caesar Wang) Date: Mon, 8 Jun 2015 15:11:35 +0800 Subject: [PATCH v5 2/3] ARM: rockchip: ensure CPU to enter WFI/WFE state In-Reply-To: <1433747496-7642-1-git-send-email-wxt@rock-chips.com> References: <1433747496-7642-1-git-send-email-wxt@rock-chips.com> Message-ID: <1433747496-7642-3-git-send-email-wxt@rock-chips.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Changes in v5: - Fix the patch decription. - Add the changelog. Changes in v4: None Changes in v3: None Changes in v2: None Changes in v2: - As Kever points out, Fix the subject typo WFI/WFE. --- 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 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 */ + mdelay(1); + pmu_set_power_domain(0 + cpu, false); return 1; } -- 1.9.1