In general, the correct flow is: cpu off: reset_control_assert regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), BIT(pd)) cpu on: regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), 0) reset_control_deassert You can repro it with bringing CPU up and down. Says:(test scripts) cd /sys/devices/system/cpu/ for i in $(seq 1000); do echo "================= $i ============" for j in $(seq 100); do while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)" != "000" ]]; do echo 0 > cpu1/online echo 0 > cpu2/online echo 0 > cpu3/online done while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)" != "111" ]]; do echo 1 > cpu1/online echo 1 > cpu2/online echo 1 > cpu3/online done done done The following is reproducile log: [34466.186812] PM: noirq suspend of devices complete after 0.669 msecs [34466.186824] Disabling non-boot CPUs ... [34466.187509] CPU1: shutdown [34466.188672] CPU2: shutdown [34473.736627] Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 0 [34473.736646] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 3.14.0 #1 [34473.736687] [<c010dfb0>] (unwind_backtrace) from [<c010a460>] (show_stack+0x20/0x24) [34473.736711] [<c010a460>] (show_stack) from [<c0630670>] (dump_stack+0x70/0x8c) [34473.736731] [<c0630670>] (dump_stack) from [<c062fa0c>] (panic+0xa8/0x1fc) [34473.736754] [<c062fa0c>] (panic) from [<c0191efc>] (watchdog_timer_fn+0x234/0x26c) [34473.736777] [<c0191efc>] (watchdog_timer_fn) from [<c014103c>] (__run_hrtimer+0x118/0x1e0) [34473.736797] [<c014103c>] (__run_hrtimer) from [<c0141c04>] (hrtimer_interrupt+0x148/0x2a0) [34473.736820] [<c0141c04>] (hrtimer_interrupt) from [<c04d9994>] (arch_timer_handler_phys+0x38/0x48) [34473.736844] [<c04d9994>] (arch_timer_handler_phys) from [<c016acc4>] (handle_percpu_devid_irq+0xb8/0x124) [34473.736867] [<c016acc4>] (handle_percpu_devid_irq) from [<c0166a30>] (generic_handle_irq+0x30/0x40) [34473.736887] [<c0166a30>] (generic_handle_irq) from [<c0166d28>] (__handle_domain_irq+0x8c/0xb0) [34473.736905] [<c0166d28>] (__handle_domain_irq) from [<c01003a0>] (gic_handle_irq+0x48/0x6c) [34473.736922] [<c01003a0>] (gic_handle_irq) from [<c010b040>] (__irq_svc+0x40/0x50) [34473.736936] Exception stack(0xee127f70 to 0xee127fb8) [34473.736948] 7f60: ffffffed 00000000 2dd6d000 00000000 [34473.736964] 7f80: ee126000 00000015 c0b46bac c0b46bac 0000406a 410fc0d1 00000000 ee127fc4 [34473.736979] 7fa0: ee127fb8 ee127fb8 c0107038 c010703c 600f0013 ffffffff [34473.736995] [<c010b040>] (__irq_svc) from [<c010703c>] (arch_cpu_idle+0x40/0x48) [34473.737013] [<c010703c>] (arch_cpu_idle) from [<c0166978>] (cpu_startup_entry+0x170/0x1d0) [34473.737031] [<c0166978>] (cpu_startup_entry) from [<c010c254>] (secondary_start_kernel+0x138/0x160) [34473.737059] [<c010c254>] (secondary_start_kernel) from [<00100464>] (0x100464) [34474.903740] SMP: failed to stop secondary CPUs [34476.099964] SMP: failed to stop secondary CPUs ... Signed-off-by: Caesar Wang <wxt at rock-chips.com> --- arch/arm/mach-rockchip/platsmp.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c index 5b4ca3c..1230d3d 100644 --- a/arch/arm/mach-rockchip/platsmp.c +++ b/arch/arm/mach-rockchip/platsmp.c @@ -88,20 +88,17 @@ static int pmu_set_power_domain(int pd, bool on) return PTR_ERR(rstc); } - if (on) + if (on) { + regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val); reset_control_deassert(rstc); - else + } else { reset_control_assert(rstc); + regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val); + } reset_control_put(rstc); } - ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val); - if (ret < 0) { - pr_err("%s: could not update power domain\n", __func__); - return ret; - } - ret = -1; while (ret != on) { ret = pmu_power_domain_is_on(pd); -- 1.9.1