/* $Id: ip27-timer.c,v 1.3 2000/02/18 09:54:40 ulfc Exp $ * * Copytight (C) 1999 Ralf Baechle (ralf@gnu.org) * Copytight (C) 1999 Silicon Graphics, Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* This is a hack; we really need to figure these values out dynamically * * Since 800 ns works very well with various HUB frequencies, such as * 360, 380, 390 and 400 MHZ, we use 800 ns rtc cycle time. * * Ralf: which clock rate is used to feed the counter? */ #define NSEC_PER_CYCLE 800 #define NSEC_PER_SEC 1000000000 #define CYCLES_PER_SEC (NSEC_PER_SEC/NSEC_PER_CYCLE) #define CYCLES_PER_JIFFY (CYCLES_PER_SEC/HZ) static unsigned long ct_cur; /* What counter should be at next timer irq */ static long last_rtc_update = 0; /* Last time the rtc clock got updated */ extern rwlock_t xtime_lock; static int set_rtc_mmss(unsigned long nowtime) { int retval = 0; int real_seconds, real_minutes, cmos_minutes; struct m48t35_rtc *rtc; nasid_t nid; nid = get_nasid(); rtc = (struct m48t35_rtc *) KL_CONFIG_CH_CONS_INFO(nid)->memory_base + IOC3_BYTEBUS_DEV0; rtc->control |= M48T35_RTC_READ; cmos_minutes = rtc->min; BCD_TO_BIN(cmos_minutes); rtc->control &= ~M48T35_RTC_READ; /* * Since we're only adjusting minutes and seconds, * don't interfere with hour overflow. This avoids * messing with unknown time zones but requires your * RTC not to be off by more than 15 minutes */ real_seconds = nowtime % 60; real_minutes = nowtime / 60; if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1) real_minutes += 30; /* correct for half hour time zone */ real_minutes %= 60; if (abs(real_minutes - cmos_minutes) < 30) { BIN_TO_BCD(real_seconds); BIN_TO_BCD(real_minutes); rtc->control |= M48T35_RTC_SET; rtc->sec = real_seconds; rtc->min = real_minutes; rtc->control &= ~M48T35_RTC_SET; } else { printk(KERN_WARNING "set_rtc_mmss: can't update from %d to %d\n", cmos_minutes, real_minutes); retval = -1; } return retval; } void rt_timer_interrupt(struct pt_regs *regs) { int cpu = smp_processor_id(); int user = user_mode(regs); int irq = 7; /* XXX Assign number */ write_lock(&xtime_lock); again: LOCAL_HUB_S(PI_RT_PEND_A, 0); /* Ack */ ct_cur += CYCLES_PER_JIFFY; LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur); if (LOCAL_HUB_L(PI_RT_COUNT) >= ct_cur) goto again; kstat.irqs[cpu][irq]++; /* kstat+do_timer only for bootcpu? */ do_timer(regs); #ifdef CONFIG_SMP if (current->pid) { unsigned int *inc, *inc2; update_one_process(current, 1, user, !user, cpu); if (--current->counter <= 0) { current->counter = 0; current->need_resched = 1; } if (user) { if (current->priority < DEF_PRIORITY) { inc = &kstat.cpu_nice; inc2 = &kstat.per_cpu_nice[cpu]; } else { inc = &kstat.cpu_user; inc2 = &kstat.per_cpu_user[cpu]; } } else { inc = &kstat.cpu_system; inc2 = &kstat.per_cpu_system[cpu]; } atomic_inc((atomic_t *)inc); atomic_inc((atomic_t *)inc2); } #endif /* CONFIG_SMP */ /* * If we have an externally synchronized Linux clock, then update * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be * called as close as possible to when a second starts. */ if ((time_status & STA_UNSYNC) == 0 && xtime.tv_sec > last_rtc_update + 660) { if (xtime.tv_usec >= 1000000 - ((unsigned) tick) / 2) { if (set_rtc_mmss(xtime.tv_sec + 1) == 0) last_rtc_update = xtime.tv_sec; else last_rtc_update = xtime.tv_sec - 600; } else if (xtime.tv_usec <= ((unsigned) tick) / 2) { if (set_rtc_mmss(xtime.tv_sec) == 0) last_rtc_update = xtime.tv_sec; else last_rtc_update = xtime.tv_sec - 600; } } write_unlock(&xtime_lock); } void do_gettimeofday(struct timeval *tv) { unsigned long flags; read_lock_irqsave(&xtime_lock, flags); *tv = xtime; read_unlock_irqrestore(&xtime_lock, flags); } void do_settimeofday(struct timeval *tv) { write_lock_irq(&xtime_lock); xtime = *tv; time_state = TIME_BAD; time_maxerror = MAXPHASE; time_esterror = MAXPHASE; write_unlock_irq(&xtime_lock); } /* Includes for ioc3_init(). */ #include #include #include #include #include /* Converts Gregorian date to seconds since 1970-01-01 00:00:00. * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 * => year=1980, mon=12, day=31, hour=23, min=59, sec=59. * * [For the Julian calendar (which was used in Russia before 1917, * Britain & colonies before 1752, anywhere else before 1582, * and is still in use by some communities) leave out the * -year/100+year/400 terms, and add 10.] * * This algorithm was first published by Gauss (I think). * * WARNING: this function will overflow on 2106-02-07 06:28:16 on * machines were long is 32-bit! (However, as time_t is signed, we * will already get problems at other places on 2038-01-19 03:14:08) */ static inline unsigned long mktime(unsigned int year, unsigned int mon, unsigned int day, unsigned int hour, unsigned int min, unsigned int sec) { if (0 >= (int) (mon -= 2)) { /* 1..12 -> 11,12,1..10 */ mon += 12; /* Puts Feb last since it has leap day */ year -= 1; } return ((( (unsigned long)(year/4 - year/100 + year/400 + 367*mon/12 + day) + year*365 - 719499 )*24 + hour /* now have hours */ )*60 + min /* now have minutes */ )*60 + sec; /* finally seconds */ } #define DEBUG_RTC static unsigned long __init get_m48t35_time(void) { unsigned int year, month, date, hour, min, sec; struct m48t35_rtc *rtc; nasid_t nid; nid = get_nasid(); rtc = (struct m48t35_rtc *)(KL_CONFIG_CH_CONS_INFO(nid)->memory_base + IOC3_BYTEBUS_DEV0); rtc->control |= M48T35_RTC_READ; sec = rtc->sec; min = rtc->min; hour = rtc->hour; date = rtc->date; month = rtc->month; year = rtc->year; rtc->control &= ~M48T35_RTC_READ; BCD_TO_BIN(sec); BCD_TO_BIN(min); BCD_TO_BIN(hour); BCD_TO_BIN(date); BCD_TO_BIN(month); BCD_TO_BIN(year); year += 1970; return mktime(year, month, date, hour, min, sec); } extern void ioc3_eth_init(void); void __init time_init(void) { xtime.tv_sec = get_m48t35_time(); xtime.tv_usec = 0; } void __init cpu_time_init(void) { lboard_t *board; klcpu_t *cpu; int cpuid; /* Don't use ARCS. ARCS is fragile. Klconfig is simple and sane. */ board = find_lboard(KL_CONFIG_INFO(get_nasid()), KLTYPE_IP27); if (!board) panic("Can't find board info for myself."); cpuid = LOCAL_HUB_L(PI_CPU_NUM) ? IP27_CPU0_INDEX : IP27_CPU1_INDEX; cpu = (klcpu_t *) KLCF_COMP(board, cpuid); if (!cpu) panic("No information about myself?"); printk("CPU %d clock is %dMHz.\n", cpu->cpu_speed, smp_processor_id()); printk("CPU clock is %dMHz.\n", cpu->cpu_speed); set_cp0_status(SRB_TIMOCLK, SRB_TIMOCLK); } void __init hub_rtc_init(cnodeid_t cnode) { /* * We only need to initialize the current node. * If this is not the current node then it is a cpuless * node and timeouts will not happen there. */ if (get_compact_nodeid() == cnode) { LOCAL_HUB_S(PI_RT_EN_A, 1); LOCAL_HUB_S(PI_RT_EN_B, 1); LOCAL_HUB_S(PI_PROF_EN_A, 0); LOCAL_HUB_S(PI_PROF_EN_B, 0); ct_cur = CYCLES_PER_JIFFY; LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur); LOCAL_HUB_S(PI_RT_COUNT, 0); LOCAL_HUB_S(PI_RT_PEND_A, 0); LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur); LOCAL_HUB_S(PI_RT_COUNT, 0); LOCAL_HUB_S(PI_RT_PEND_B, 0); } }