diff options
| -rw-r--r-- | arch/powerpc/kernel/time.c | 79 | ||||
| -rw-r--r-- | include/asm-powerpc/time.h | 14 |
2 files changed, 69 insertions, 24 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index b635c7d..ad501d6 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -126,6 +126,16 @@ unsigned long ppc_tb_freq; #define boot_cpuid 0 #endif +u64 tb_last_jiffy __cacheline_aligned_in_smp; +unsigned long tb_last_stamp; + +/* + * Note that on ppc32 this only stores the bottom 32 bits of + * the timebase value, but that's enough to tell when a jiffy + * has passed. + */ +DEFINE_PER_CPU(unsigned long, last_jiffy); + static __inline__ void timer_check_rtc(void) { /* @@ -191,6 +201,26 @@ static inline void __do_gettimeofday(struct timeval *tv, u64 tb_val) void do_gettimeofday(struct timeval *tv) { + if (__USE_RTC()) { + /* do this the old way */ + unsigned long flags, seq; + unsigned int sec, nsec, usec, lost; + + do { + seq = read_seqbegin_irqsave(&xtime_lock, flags); + sec = xtime.tv_sec; + nsec = xtime.tv_nsec + tb_ticks_since(tb_last_stamp); + lost = jiffies - wall_jiffies; + } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); + usec = nsec / 1000 + lost * (1000000 / HZ); + while (usec >= 1000000) { + usec -= 1000000; + ++sec; + } + tv->tv_sec = sec; + tv->tv_usec = usec; + return; + } __do_gettimeofday(tv, get_tb()); } @@ -272,6 +302,8 @@ static __inline__ void timer_recalc_offset(u64 cur_tb) unsigned long offset; u64 new_stamp_xsec; + if (__USE_RTC()) + return; offset = cur_tb - do_gtod.varp->tb_orig_stamp; if ((offset & 0x80000000u) == 0) return; @@ -357,15 +389,6 @@ static void iSeries_tb_recal(void) * call will not be needed) */ -u64 tb_last_stamp __cacheline_aligned_in_smp; - -/* - * Note that on ppc32 this only stores the bottom 32 bits of - * the timebase value, but that's enough to tell when a jiffy - * has passed. - */ -DEFINE_PER_CPU(unsigned long, last_jiffy); - /* * timer_interrupt - gets called when the decrementer overflows, * with interrupts disabled. @@ -415,10 +438,11 @@ void timer_interrupt(struct pt_regs * regs) continue; write_seqlock(&xtime_lock); - tb_last_stamp += tb_ticks_per_jiffy; - timer_recalc_offset(tb_last_stamp); + tb_last_jiffy += tb_ticks_per_jiffy; + tb_last_stamp = per_cpu(last_jiffy, cpu); + timer_recalc_offset(tb_last_jiffy); do_timer(regs); - timer_sync_xtime(tb_last_stamp); + timer_sync_xtime(tb_last_jiffy); timer_check_rtc(); write_sequnlock(&xtime_lock); if (adjusting_time && (time_adjust == 0)) @@ -453,7 +477,7 @@ void wakeup_decrementer(void) * We don't expect this to be called on a machine with a 601, * so using get_tbl is fine. */ - tb_last_stamp = get_tb(); + tb_last_stamp = tb_last_jiffy = get_tb(); for_each_cpu(i) per_cpu(last_jiffy, i) = tb_last_stamp; } @@ -483,6 +507,8 @@ void __init smp_space_timers(unsigned int max_cpus) */ unsigned long long sched_clock(void) { + if (__USE_RTC()) + return get_rtc(); return mulhdu(get_tb(), tb_to_ns_scale) << tb_to_ns_shift; } @@ -534,7 +560,7 @@ int do_settimeofday(struct timespec *tv) new_xsec = (u64)new_nsec * XSEC_PER_SEC; do_div(new_xsec, NSEC_PER_SEC); new_xsec += (u64)new_sec * XSEC_PER_SEC; - update_gtod(tb_last_stamp, new_xsec, do_gtod.varp->tb_to_xs); + update_gtod(tb_last_jiffy, new_xsec, do_gtod.varp->tb_to_xs); #ifdef CONFIG_PPC64 systemcfg->tz_minuteswest = sys_tz.tz_minuteswest; @@ -616,12 +642,20 @@ void __init time_init(void) if (ppc_md.time_init != NULL) timezone_offset = ppc_md.time_init(); - ppc_md.calibrate_decr(); - - printk(KERN_INFO "time_init: decrementer frequency = %lu.%.6lu MHz\n", - ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); - printk(KERN_INFO "time_init: processor frequency = %lu.%.6lu MHz\n", - ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); + if (__USE_RTC()) { + /* 601 processor: dec counts down by 128 every 128ns */ + ppc_tb_freq = 1000000000; + tb_last_stamp = get_rtcl(); + tb_last_jiffy = tb_last_stamp; + } else { + /* Normal PowerPC with timebase register */ + ppc_md.calibrate_decr(); + printk(KERN_INFO "time_init: decrementer frequency = %lu.%.6lu MHz\n", + ppc_tb_freq / 1000000, ppc_tb_freq % 1000000); + printk(KERN_INFO "time_init: processor frequency = %lu.%.6lu MHz\n", + ppc_proc_freq / 1000000, ppc_proc_freq % 1000000); + tb_last_stamp = tb_last_jiffy = get_tb(); + } tb_ticks_per_jiffy = ppc_tb_freq / HZ; tb_ticks_per_sec = tb_ticks_per_jiffy * HZ; @@ -661,17 +695,16 @@ void __init time_init(void) write_seqlock_irqsave(&xtime_lock, flags); xtime.tv_sec = tm; xtime.tv_nsec = 0; - tb_last_stamp = get_tb(); do_gtod.varp = &do_gtod.vars[0]; do_gtod.var_idx = 0; - do_gtod.varp->tb_orig_stamp = tb_last_stamp; + do_gtod.varp->tb_orig_stamp = tb_last_jiffy; __get_cpu_var(last_jiffy) = tb_last_stamp; do_gtod.varp->stamp_xsec = (u64) xtime.tv_sec * XSEC_PER_SEC; do_gtod.tb_ticks_per_sec = tb_ticks_per_sec; do_gtod.varp->tb_to_xs = tb_to_xs; do_gtod.tb_to_us = tb_to_us; #ifdef CONFIG_PPC64 - systemcfg->tb_orig_stamp = tb_last_stamp; + systemcfg->tb_orig_stamp = tb_last_jiffy; systemcfg->tb_update_count = 0; systemcfg->tb_ticks_per_sec = tb_ticks_per_sec; systemcfg->stamp_xsec = xtime.tv_sec * XSEC_PER_SEC; diff --git a/include/asm-powerpc/time.h b/include/asm-powerpc/time.h index 99bfe32..410e795 100644 --- a/include/asm-powerpc/time.h +++ b/include/asm-powerpc/time.h @@ -30,7 +30,8 @@ extern unsigned long tb_ticks_per_usec; extern unsigned long tb_ticks_per_sec; extern u64 tb_to_xs; extern unsigned tb_to_us; -extern u64 tb_last_stamp; +extern unsigned long tb_last_stamp; +extern u64 tb_last_jiffy; DECLARE_PER_CPU(unsigned long, last_jiffy); @@ -113,6 +114,17 @@ static inline unsigned int get_rtcl(void) return rtcl; } +static inline u64 get_rtc(void) +{ + unsigned int hi, lo, hi2; + + do { + asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2" + : "=r" (hi), "=r" (lo), "=r" (hi2)); + } while (hi2 != hi); + return (u64)hi * 1000000000 + lo; +} + #ifdef CONFIG_PPC64 static inline u64 get_tb(void) { |