diff options
Diffstat (limited to 'arch/arm/kernel/sched_clock.c')
| -rw-r--r-- | arch/arm/kernel/sched_clock.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/arm/kernel/sched_clock.c b/arch/arm/kernel/sched_clock.c index 27d186abbc0..f4515393248 100644 --- a/arch/arm/kernel/sched_clock.c +++ b/arch/arm/kernel/sched_clock.c @@ -21,6 +21,8 @@ struct clock_data { u32 epoch_cyc_copy; u32 mult; u32 shift; + bool suspended; + bool needs_suspend; }; static void sched_clock_poll(unsigned long wrap_ticks); @@ -49,6 +51,9 @@ static unsigned long long cyc_to_sched_clock(u32 cyc, u32 mask) u64 epoch_ns; u32 epoch_cyc; + if (cd.suspended) + return cd.epoch_ns; + /* * Load the epoch_cyc and epoch_ns atomically. We do this by * ensuring that we always write epoch_cyc, epoch_ns and @@ -98,6 +103,13 @@ static void sched_clock_poll(unsigned long wrap_ticks) update_sched_clock(); } +void __init setup_sched_clock_needs_suspend(u32 (*read)(void), int bits, + unsigned long rate) +{ + setup_sched_clock(read, bits, rate); + cd.needs_suspend = true; +} + void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate) { unsigned long r, w; @@ -169,11 +181,23 @@ void __init sched_clock_postinit(void) static int sched_clock_suspend(void) { sched_clock_poll(sched_clock_timer.data); + if (cd.needs_suspend) + cd.suspended = true; return 0; } +static void sched_clock_resume(void) +{ + if (cd.needs_suspend) { + cd.epoch_cyc = read_sched_clock(); + cd.epoch_cyc_copy = cd.epoch_cyc; + cd.suspended = false; + } +} + static struct syscore_ops sched_clock_ops = { .suspend = sched_clock_suspend, + .resume = sched_clock_resume, }; static int __init sched_clock_syscore_init(void) |