From: Tony Lindgren <tony@xxxxxxxxxxx> OMAP4 uses full SoC suspend modes as idle states, as such it needs the whole power-domain and clock-domain code from the idle path. All that code is not suitable to run with RCU disabled, as such push RCU-idle deeper still. Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/Yqcv6crSNKuSWoTu@xxxxxxxxxxx --- arch/arm/mach-omap2/common.h | 6 ++++-- arch/arm/mach-omap2/cpuidle44xx.c | 8 ++------ arch/arm/mach-omap2/omap-mpuss-lowpower.c | 12 +++++++++++- arch/arm/mach-omap2/pm44xx.c | 2 +- 4 files changed, 18 insertions(+), 10 deletions(-) --- a/arch/arm/mach-omap2/common.h +++ b/arch/arm/mach-omap2/common.h @@ -284,11 +284,13 @@ extern u32 omap4_get_cpu1_ns_pa_addr(voi #if defined(CONFIG_SMP) && defined(CONFIG_PM) extern int omap4_mpuss_init(void); -extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state); +extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state, + bool rcuidle); extern int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state); #else static inline int omap4_enter_lowpower(unsigned int cpu, - unsigned int power_state) + unsigned int power_state, + bool rcuidle) { cpu_do_idle(); return 0; --- a/arch/arm/mach-omap2/cpuidle44xx.c +++ b/arch/arm/mach-omap2/cpuidle44xx.c @@ -105,9 +105,7 @@ static int omap_enter_idle_smp(struct cp } raw_spin_unlock_irqrestore(&mpu_lock, flag); - ct_cpuidle_enter(); - omap4_enter_lowpower(dev->cpu, cx->cpu_state); - ct_cpuidle_exit(); + omap4_enter_lowpower(dev->cpu, cx->cpu_state, true); raw_spin_lock_irqsave(&mpu_lock, flag); if (cx->mpu_state_vote == num_online_cpus()) @@ -186,10 +184,8 @@ static int omap_enter_idle_coupled(struc } } - ct_cpuidle_enter(); - omap4_enter_lowpower(dev->cpu, cx->cpu_state); + omap4_enter_lowpower(dev->cpu, cx->cpu_state, true); cpu_done[dev->cpu] = true; - ct_cpuidle_exit(); /* Wakeup CPU1 only if it is not offlined */ if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) { --- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c +++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c @@ -33,6 +33,7 @@ * and first to wake-up when MPUSS low power states are excercised */ +#include <linux/cpuidle.h> #include <linux/kernel.h> #include <linux/io.h> #include <linux/errno.h> @@ -214,6 +215,7 @@ static void __init save_l2x0_context(voi * of OMAP4 MPUSS subsystem * @cpu : CPU ID * @power_state: Low power state. + * @rcuidle: RCU needs to be idled * * MPUSS states for the context save: * save_state = @@ -222,7 +224,8 @@ static void __init save_l2x0_context(voi * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF */ -int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state) +int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state, + bool rcuidle) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET; @@ -268,6 +271,10 @@ int omap4_enter_lowpower(unsigned int cp cpu_clear_prev_logic_pwrst(cpu); pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state); + + if (rcuidle) + ct_cpuidle_enter(); + set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.resume)); omap_pm_ops.scu_prepare(cpu, power_state); l2x0_pwrst_prepare(cpu, save_state); @@ -283,6 +290,9 @@ int omap4_enter_lowpower(unsigned int cp if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu) gic_dist_enable(); + if (rcuidle) + ct_cpuidle_exit(); + /* * Restore the CPUx power state to ON otherwise CPUx * power domain can transitions to programmed low power --- a/arch/arm/mach-omap2/pm44xx.c +++ b/arch/arm/mach-omap2/pm44xx.c @@ -76,7 +76,7 @@ static int omap4_pm_suspend(void) * domain CSWR is not supported by hardware. * More details can be found in OMAP4430 TRM section 4.3.4.2. */ - omap4_enter_lowpower(cpu_id, cpu_suspend_state); + omap4_enter_lowpower(cpu_id, cpu_suspend_state, false); /* Restore next powerdomain state */ list_for_each_entry(pwrst, &pwrst_list, node) {