diff options
Diffstat (limited to 'arch/arm/kernel/smp_twd.c')
| -rw-r--r-- | arch/arm/kernel/smp_twd.c | 30 |
1 files changed, 29 insertions, 1 deletions
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 7a79b24597b..007f7f6aee8 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -31,6 +31,9 @@ void __iomem *twd_base; static struct clk *twd_clk; static unsigned long twd_timer_rate; +static DEFINE_PER_CPU(u32, twd_ctrl); +static DEFINE_PER_CPU(u32, twd_load); + static struct clock_event_device __percpu **twd_evt; static void twd_set_mode(enum clock_event_mode mode, @@ -115,10 +118,14 @@ static int twd_cpufreq_transition(struct notifier_block *nb, * The twd clock events must be reprogrammed to account for the new * frequency. The timer is local to a cpu, so cross-call to the * changing cpu. + * + * Only wait for it to finish, if the cpu is active to avoid + * deadlock when cpu1 is spinning on while(!cpu_active(cpu1)) during + * booting of that cpu. */ if (state == CPUFREQ_POSTCHANGE || state == CPUFREQ_RESUMECHANGE) smp_call_function_single(freqs->cpu, twd_update_frequency, - NULL, 1); + NULL, cpu_active(freqs->cpu)); return NOTIFY_OK; } @@ -268,3 +275,24 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk) 0xf, 0xffffffff); enable_percpu_irq(clk->irq, 0); } + +#if defined(CONFIG_HOTPLUG) || defined(CONFIG_CPU_IDLE) +void twd_save(void) +{ + int this_cpu = smp_processor_id(); + + per_cpu(twd_ctrl, this_cpu) = __raw_readl(twd_base + TWD_TIMER_CONTROL); + per_cpu(twd_load, this_cpu) = __raw_readl(twd_base + TWD_TIMER_LOAD); + +} + +void twd_restore(void) +{ + int this_cpu = smp_processor_id(); + + __raw_writel(per_cpu(twd_ctrl, this_cpu), + twd_base + TWD_TIMER_CONTROL); + __raw_writel(per_cpu(twd_load, this_cpu), + twd_base + TWD_TIMER_LOAD); +} +#endif |