diff options
author | Stefan Richter <stefanr@s5r6.in-berlin.de> | 2010-02-24 20:31:04 +0100 |
---|---|---|
committer | Stefan Richter <stefanr@s5r6.in-berlin.de> | 2010-02-24 20:33:45 +0100 |
commit | 109d28152b6e9d5de64cd23e3bc08885ccb3d1ef (patch) | |
tree | b7b8863faa05254781acfb85cc41da3eef467c6b /arch/arm/plat-omap/common.c | |
parent | 168cf9af699e87d5a6f44b684583714ecabb8e71 (diff) | |
parent | 60b341b778cc2929df16c0a504c91621b3c6a4ad (diff) |
Merge tag 'v2.6.33' for its firewire changes since last branch point
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Diffstat (limited to 'arch/arm/plat-omap/common.c')
-rw-r--r-- | arch/arm/plat-omap/common.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/common.c b/arch/arm/plat-omap/common.c index bf1eaf3a27d..dddc0273bc8 100644 --- a/arch/arm/plat-omap/common.c +++ b/arch/arm/plat-omap/common.c @@ -172,6 +172,32 @@ unsigned long long sched_clock(void) clocksource_32k.mult, clocksource_32k.shift); } +/** + * read_persistent_clock - Return time from a persistent clock. + * + * Reads the time from a source which isn't disabled during PM, the + * 32k sync timer. Convert the cycles elapsed since last read into + * nsecs and adds to a monotonically increasing timespec. + */ +static struct timespec persistent_ts; +static cycles_t cycles, last_cycles; +void read_persistent_clock(struct timespec *ts) +{ + unsigned long long nsecs; + cycles_t delta; + struct timespec *tsp = &persistent_ts; + + last_cycles = cycles; + cycles = clocksource_32k.read(&clocksource_32k); + delta = cycles - last_cycles; + + nsecs = clocksource_cyc2ns(delta, + clocksource_32k.mult, clocksource_32k.shift); + + timespec_add_ns(tsp, nsecs); + *ts = *tsp; +} + static int __init omap_init_clocksource_32k(void) { static char err[] __initdata = KERN_ERR |