diff options
Diffstat (limited to 'arch/s390/kernel/time.c')
| -rw-r--r-- | arch/s390/kernel/time.c | 125 |
1 files changed, 39 insertions, 86 deletions
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 74e6178fbaf2..6cceed4df73e 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -28,12 +28,14 @@ #include <linux/profile.h> #include <linux/timex.h> #include <linux/notifier.h> +#include <linux/clocksource.h> #include <asm/uaccess.h> #include <asm/delay.h> #include <asm/s390_ext.h> #include <asm/div64.h> #include <asm/irq.h> +#include <asm/irq_regs.h> #include <asm/timer.h> /* change this if you have some constant time drift */ @@ -53,8 +55,6 @@ static u64 init_timer_cc; static u64 jiffies_timer_cc; static u64 xtime_cc; -extern unsigned long wall_jiffies; - /* * Scheduler clock - returns current time in nanosec units. */ @@ -83,79 +83,10 @@ void tod_to_timeval(__u64 todval, struct timespec *xtime) xtime->tv_nsec = ((todval * 1000) >> 12); } -static inline unsigned long do_gettimeoffset(void) -{ - __u64 now; - - now = (get_clock() - jiffies_timer_cc) >> 12; - /* We require the offset from the latest update of xtime */ - now -= (__u64) wall_jiffies*USECS_PER_JIFFY; - return (unsigned long) now; -} - -/* - * This version of gettimeofday has microsecond resolution. - */ -void do_gettimeofday(struct timeval *tv) -{ - unsigned long flags; - unsigned long seq; - unsigned long usec, sec; - - do { - seq = read_seqbegin_irqsave(&xtime_lock, flags); - - sec = xtime.tv_sec; - usec = xtime.tv_nsec / 1000 + do_gettimeoffset(); - } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); - - while (usec >= 1000000) { - usec -= 1000000; - sec++; - } - - tv->tv_sec = sec; - tv->tv_usec = usec; -} - -EXPORT_SYMBOL(do_gettimeofday); - -int do_settimeofday(struct timespec *tv) -{ - time_t wtm_sec, sec = tv->tv_sec; - long wtm_nsec, nsec = tv->tv_nsec; - - if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) - return -EINVAL; - - write_seqlock_irq(&xtime_lock); - /* This is revolting. We need to set the xtime.tv_nsec - * correctly. However, the value in this location is - * is value at the last tick. - * Discover what correction gettimeofday - * would have done, and then undo it! - */ - nsec -= do_gettimeoffset() * 1000; - - wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); - wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); - - set_normalized_timespec(&xtime, sec, nsec); - set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); - - ntp_clear(); - write_sequnlock_irq(&xtime_lock); - clock_was_set(); - return 0; -} - -EXPORT_SYMBOL(do_settimeofday); - - #ifdef CONFIG_PROFILING -#define s390_do_profile(regs) profile_tick(CPU_PROFILING, regs) +#define s390_do_profile() profile_tick(CPU_PROFILING) #else -#define s390_do_profile(regs) do { ; } while(0) +#define s390_do_profile() do { ; } while(0) #endif /* CONFIG_PROFILING */ @@ -163,10 +94,10 @@ EXPORT_SYMBOL(do_settimeofday); * timer_interrupt() needs to keep up the real-time clock, * as well as call the "do_timer()" routine every clocktick */ -void account_ticks(struct pt_regs *regs) +void account_ticks(void) { __u64 tmp; - __u32 ticks, xticks; + __u32 ticks; /* Calculate how many ticks have passed. */ if (S390_lowcore.int_clock < S390_lowcore.jiffy_timer) { @@ -204,6 +135,7 @@ void account_ticks(struct pt_regs *regs) */ write_seqlock(&xtime_lock); if (S390_lowcore.jiffy_timer > xtime_cc) { + __u32 xticks; tmp = S390_lowcore.jiffy_timer - xtime_cc; if (tmp >= 2*CLK_TICKS_PER_JIFFY) { xticks = __div(tmp, CLK_TICKS_PER_JIFFY); @@ -212,23 +144,21 @@ void account_ticks(struct pt_regs *regs) xticks = 1; xtime_cc += CLK_TICKS_PER_JIFFY; } - while (xticks--) - do_timer(regs); + do_timer(xticks); } write_sequnlock(&xtime_lock); #else - for (xticks = ticks; xticks > 0; xticks--) - do_timer(regs); + do_timer(ticks); #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING account_tick_vtime(current); #else while (ticks--) - update_process_times(user_mode(regs)); + update_process_times(user_mode(get_irq_regs())); #endif - s390_do_profile(regs); + s390_do_profile(); } #ifdef CONFIG_NO_IDLE_HZ @@ -289,9 +219,11 @@ static inline void stop_hz_timer(void) */ static inline void start_hz_timer(void) { + BUG_ON(!in_interrupt()); + if (!cpu_isset(smp_processor_id(), nohz_cpu_mask)) return; - account_ticks(task_pt_regs(current)); + account_ticks(); cpu_clear(smp_processor_id(), nohz_cpu_mask); } @@ -341,6 +273,22 @@ void init_cpu_timer(void) extern void vtime_init(void); +static cycle_t read_tod_clock(void) +{ + return get_clock(); +} + +static struct clocksource clocksource_tod = { + .name = "tod", + .rating = 100, + .read = read_tod_clock, + .mask = -1ULL, + .mult = 1000, + .shift = 12, + .is_continuous = 1, +}; + + /* * Initialize the TOD clock and the CPU timer of * the boot cpu. @@ -351,10 +299,12 @@ void __init time_init(void) int cc; /* kick the TOD clock */ - asm volatile ("STCK 0(%1)\n\t" - "IPM %0\n\t" - "SRL %0,28" : "=r" (cc) : "a" (&init_timer_cc) - : "memory", "cc"); + asm volatile( + " stck 0(%2)\n" + " ipm %0\n" + " srl %0,28" + : "=d" (cc), "=m" (init_timer_cc) + : "a" (&init_timer_cc) : "cc"); switch (cc) { case 0: /* clock in set state: all is fine */ break; @@ -383,6 +333,9 @@ void __init time_init(void) &ext_int_info_cc) != 0) panic("Couldn't request external interrupt 0x1004"); + if (clocksource_register(&clocksource_tod) != 0) + panic("Could not register TOD clock source"); + init_cpu_timer(); #ifdef CONFIG_NO_IDLE_HZ |