/* $Id: time.c,v 1.51 2000/01/29 01:08:59 anton Exp $ * linux/arch/sparc/kernel/time.c * * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu) * * Chris Davis (cdavis@cois.on.ca) 03/27/1998 * Added support for the intersil on the sun4/4200 * * Gleb Raiko (rajko@mech.math.msu.su) 08/18/1998 * Support for MicroSPARC-IIep, PCI CPU. * * This file handles the Sparc specific time handling details. * * 1997-09-10 Updated NTP code according to technical memorandum Jan '96 * "A Kernel Model for Precision Timekeeping" by Dave Mills */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern rwlock_t xtime_lock; enum sparc_clock_type sp_clock_typ; unsigned long mstk48t02_regs = 0UL; static struct mostek48t08 *mstk48t08_regs = 0; static int set_rtc_mmss(unsigned long); static void sbus_do_settimeofday(struct timeval *tv); #ifdef CONFIG_SUN4 struct intersil *intersil_clock; #define intersil_cmd(intersil_reg, intsil_cmd) intersil_reg->int_cmd_reg = \ (intsil_cmd) #define intersil_intr(intersil_reg, intsil_cmd) intersil_reg->int_intr_reg = \ (intsil_cmd) #define intersil_start(intersil_reg) intersil_cmd(intersil_reg, \ ( INTERSIL_START | INTERSIL_32K | INTERSIL_NORMAL | INTERSIL_24H |\ INTERSIL_INTR_ENABLE)) #define intersil_stop(intersil_reg) intersil_cmd(intersil_reg, \ ( INTERSIL_STOP | INTERSIL_32K | INTERSIL_NORMAL | INTERSIL_24H |\ INTERSIL_INTR_ENABLE)) #define intersil_read_intr(intersil_reg, towhere) towhere = \ intersil_reg->int_intr_reg #endif __volatile__ unsigned int *master_l10_counter; __volatile__ unsigned int *master_l10_limit; /* * timer_interrupt() needs to keep up the real-time clock, * as well as call the "do_timer()" routine every clocktick */ void timer_interrupt(int irq, void *dev_id, struct pt_regs * regs) { /* last time the cmos clock got updated */ static long last_rtc_update=0; #ifdef CONFIG_SUN4 if((idprom->id_machtype == (SM_SUN4 | SM_4_260)) || (idprom->id_machtype == (SM_SUN4 | SM_4_110))) { int temp; intersil_read_intr(intersil_clock, temp); /* re-enable the irq */ enable_pil_irq(10); } #endif clear_clock_irq(); write_lock(&xtime_lock); do_timer(regs); /* Determine when to update the Mostek clock. */ if ((time_status & STA_UNSYNC) == 0 && xtime.tv_sec > last_rtc_update + 660 && xtime.tv_usec >= 500000 - ((unsigned) tick) / 2 && xtime.tv_usec <= 500000 + ((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; /* do it again in 60 s */ } write_unlock(&xtime_lock); } /* 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 */ } /* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */ static void __init kick_start_clock(void) { struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs; unsigned char sec; int i, count; prom_printf("CLOCK: Clock was stopped. Kick start "); /* Turn on the kick start bit to start the oscillator. */ regs->creg |= MSTK_CREG_WRITE; regs->sec &= ~MSTK_STOP; regs->hour |= MSTK_KICK_START; regs->creg &= ~MSTK_CREG_WRITE; /* Delay to allow the clock oscillator to start. */ sec = MSTK_REG_SEC(regs); for (i = 0; i < 3; i++) { while (sec == MSTK_REG_SEC(regs)) for (count = 0; count < 100000; count++) /* nothing */ ; prom_printf("."); sec = regs->sec; } prom_printf("\n"); /* Turn off kick start and set a "valid" time and date. */ regs->creg |= MSTK_CREG_WRITE; regs->hour &= ~MSTK_KICK_START; MSTK_SET_REG_SEC(regs,0); MSTK_SET_REG_MIN(regs,0); MSTK_SET_REG_HOUR(regs,0); MSTK_SET_REG_DOW(regs,5); MSTK_SET_REG_DOM(regs,1); MSTK_SET_REG_MONTH(regs,8); MSTK_SET_REG_YEAR(regs,1996 - MSTK_YEAR_ZERO); regs->creg &= ~MSTK_CREG_WRITE; /* Ensure the kick start bit is off. If it isn't, turn it off. */ while (regs->hour & MSTK_KICK_START) { prom_printf("CLOCK: Kick start still on!\n"); regs->creg |= MSTK_CREG_WRITE; regs->hour &= ~MSTK_KICK_START; regs->creg &= ~MSTK_CREG_WRITE; } prom_printf("CLOCK: Kick start procedure successful.\n"); } /* Return nonzero if the clock chip battery is low. */ static __inline__ int has_low_battery(void) { struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs; unsigned char data1, data2; data1 = regs->eeprom[0]; /* Read some data. */ regs->eeprom[0] = ~data1; /* Write back the complement. */ data2 = regs->eeprom[0]; /* Read back the complement. */ regs->eeprom[0] = data1; /* Restore the original value. */ return (data1 == data2); /* Was the write blocked? */ } /* Probe for the real time clock chip on Sun4 */ static __inline__ void sun4_clock_probe(void) { #ifdef CONFIG_SUN4 int temp; struct resource r; memset(&r, 0, sizeof(r)); if( idprom->id_machtype == (SM_SUN4 | SM_4_330) ) { sp_clock_typ = MSTK48T02; r.start = sun4_clock_physaddr; mstk48t02_regs = sbus_ioremap(&r, 0, sizeof(struct mostek48t02), 0); mstk48t08_regs = 0; /* To catch weirdness */ intersil_clock = 0; /* just in case */ /* Kick start the clock if it is completely stopped. */ if (mostek_read(mstk48t02_regs + MOSTEK_SEC) & MSTK_STOP) kick_start_clock(); } else if( idprom->id_machtype == (SM_SUN4 | SM_4_260)) { /* intersil setup code */ printk("Clock: INTERSIL at %8x ",sun4_clock_physaddr); sp_clock_typ = INTERSIL; r.start = sun4_clock_physaddr; intersil_clock = (struct intersil *) sbus_ioremap(&r, 0, sizeof(*intersil_clock), "intersil"); mstk48t02_regs = 0; /* just be sure */ mstk48t08_regs = 0; /* ditto */ /* initialise the clock */ intersil_intr(intersil_clock,INTERSIL_INT_100HZ); intersil_start(intersil_clock); intersil_read_intr(intersil_clock, temp); while (!(temp & 0x80)) intersil_read_intr(intersil_clock, temp); intersil_read_intr(intersil_clock, temp); while (!(temp & 0x80)) intersil_read_intr(intersil_clock, temp); intersil_stop(intersil_clock); } #endif } /* Probe for the mostek real time clock chip. */ static __inline__ void clock_probe(void) { struct linux_prom_registers clk_reg[2]; char model[128]; register int node, cpuunit, bootbus; struct resource r; cpuunit = bootbus = 0; memset(&r, 0, sizeof(r)); /* Determine the correct starting PROM node for the probe. */ node = prom_getchild(prom_root_node); switch (sparc_cpu_model) { case sun4c: break; case sun4m: node = prom_getchild(prom_searchsiblings(node, "obio")); break; case sun4d: node = prom_getchild(bootbus = prom_searchsiblings(prom_getchild(cpuunit = prom_searchsiblings(node, "cpu-unit")), "bootbus")); break; default: prom_printf("CLOCK: Unsupported architecture!\n"); prom_halt(); } /* Find the PROM node describing the real time clock. */ sp_clock_typ = MSTK_INVALID; node = prom_searchsiblings(node,"eeprom"); if (!node) { prom_printf("CLOCK: No clock found!\n"); prom_halt(); } /* Get the model name and setup everything up. */ model[0] = '\0'; prom_getstring(node, "model", model, sizeof(model)); if (strcmp(model, "mk48t02") == 0) { sp_clock_typ = MSTK48T02; if (prom_getproperty(node, "reg", (char *) clk_reg, sizeof(clk_reg)) == -1) { prom_printf("clock_probe: FAILED!\n"); prom_halt(); } if (sparc_cpu_model == sun4d) prom_apply_generic_ranges (bootbus, cpuunit, clk_reg, 1); else prom_apply_obio_ranges(clk_reg, 1); /* Map the clock register io area read-only */ r.flags = clk_reg[0].which_io; r.start = clk_reg[0].phys_addr; mstk48t02_regs = sbus_ioremap(&r, 0, sizeof(struct mostek48t02), "mk48t02"); mstk48t08_regs = 0; /* To catch weirdness */ } else if (strcmp(model, "mk48t08") == 0) { sp_clock_typ = MSTK48T08; if(prom_getproperty(node, "reg", (char *) clk_reg, sizeof(clk_reg)) == -1) { prom_printf("clock_probe: FAILED!\n"); prom_halt(); } if (sparc_cpu_model == sun4d) prom_apply_generic_ranges (bootbus, cpuunit, clk_reg, 1); else prom_apply_obio_ranges(clk_reg, 1); /* Map the clock register io area read-only */ /* XXX r/o attribute is somewhere in r.flags */ r.flags = clk_reg[0].which_io; r.start = clk_reg[0].phys_addr; mstk48t08_regs = (struct mostek48t08 *) sbus_ioremap(&r, 0, sizeof(struct mostek48t08), "mk48t08"); mstk48t02_regs = (unsigned long)&mstk48t08_regs->regs; } else { prom_printf("CLOCK: Unknown model name '%s'\n",model); prom_halt(); } /* Report a low battery voltage condition. */ if (has_low_battery()) printk(KERN_CRIT "NVRAM: Low battery voltage!\n"); /* Kick start the clock if it is completely stopped. */ if (mostek_read(mstk48t02_regs + MOSTEK_SEC) & MSTK_STOP) kick_start_clock(); } void __init sbus_time_init(void) { unsigned int year, mon, day, hour, min, sec; struct mostek48t02 *mregs; #ifdef CONFIG_SUN4 int temp; struct intersil *iregs; #endif do_get_fast_time = do_gettimeofday; BTFIXUPSET_CALL(bus_do_settimeofday, sbus_do_settimeofday, BTFIXUPCALL_NORM); btfixup(); if (ARCH_SUN4) sun4_clock_probe(); else clock_probe(); init_timers(timer_interrupt); #ifdef CONFIG_SUN4 if(idprom->id_machtype == (SM_SUN4 | SM_4_330)) { #endif mregs = (struct mostek48t02 *)mstk48t02_regs; if(!mregs) { prom_printf("Something wrong, clock regs not mapped yet.\n"); prom_halt(); } mregs->creg |= MSTK_CREG_READ; sec = MSTK_REG_SEC(mregs); min = MSTK_REG_MIN(mregs); hour = MSTK_REG_HOUR(mregs); day = MSTK_REG_DOM(mregs); mon = MSTK_REG_MONTH(mregs); year = MSTK_CVT_YEAR( MSTK_REG_YEAR(mregs) ); xtime.tv_sec = mktime(year, mon, day, hour, min, sec); xtime.tv_usec = 0; mregs->creg &= ~MSTK_CREG_READ; #ifdef CONFIG_SUN4 } else if(idprom->id_machtype == (SM_SUN4 | SM_4_260) ) { /* initialise the intersil on sun4 */ iregs=intersil_clock; if(!iregs) { prom_printf("Something wrong, clock regs not mapped yet.\n"); prom_halt(); } intersil_intr(intersil_clock,INTERSIL_INT_100HZ); disable_pil_irq(10); intersil_stop(iregs); intersil_read_intr(intersil_clock, temp); temp = iregs->clk.int_csec; sec = iregs->clk.int_sec; min = iregs->clk.int_min; hour = iregs->clk.int_hour; day = iregs->clk.int_day; mon = iregs->clk.int_month; year = MSTK_CVT_YEAR(iregs->clk.int_year); enable_pil_irq(10); intersil_start(iregs); xtime.tv_sec = mktime(year, mon, day, hour, min, sec); xtime.tv_usec = 0; printk("%u/%u/%u %u:%u:%u\n",day,mon,year,hour,min,sec); } #endif /* Now that OBP ticker has been silenced, it is safe to enable IRQ. */ __sti(); } void __init time_init(void) { #ifdef CONFIG_PCI extern void pci_time_init(void); if (pcic_present()) { pci_time_init(); return; } #endif sbus_time_init(); } extern __inline__ unsigned long do_gettimeoffset(void) { unsigned long offset = 0; unsigned int count; count = (*master_l10_counter >> 10) & 0x1fffff; if(test_bit(TIMER_BH, &bh_active)) offset = 1000000; return offset + count; } /* This need not obtain the xtime_lock as it is coded in * an implicitly SMP safe way already. */ void do_gettimeofday(struct timeval *tv) { /* Load doubles must be used on xtime so that what we get * is guarenteed to be atomic, this is why we can run this * with interrupts on full blast. Don't touch this... -DaveM */ __asm__ __volatile__(" sethi %hi(master_l10_counter), %o1 ld [%o1 + %lo(master_l10_counter)], %g3 sethi %hi(xtime), %g2 1: ldd [%g2 + %lo(xtime)], %o4 ld [%g3], %o1 ldd [%g2 + %lo(xtime)], %o2 xor %o4, %o2, %o2 xor %o5, %o3, %o3 orcc %o2, %o3, %g0 bne 1b cmp %o1, 0 bge 1f srl %o1, 0xa, %o1 sethi %hi(tick), %o3 ld [%o3 + %lo(tick)], %o3 sethi %hi(0x1fffff), %o2 or %o2, %lo(0x1fffff), %o2 add %o5, %o3, %o5 and %o1, %o2, %o1 1: add %o5, %o1, %o5 sethi %hi(1000000), %o2 or %o2, %lo(1000000), %o2 cmp %o5, %o2 bl,a 1f st %o4, [%o0 + 0x0] add %o4, 0x1, %o4 sub %o5, %o2, %o5 st %o4, [%o0 + 0x0] 1: st %o5, [%o0 + 0x4]"); } void do_settimeofday(struct timeval *tv) { write_lock_irq(&xtime_lock); bus_do_settimeofday(tv); write_unlock_irq(&xtime_lock); } static void sbus_do_settimeofday(struct timeval *tv) { tv->tv_usec -= do_gettimeoffset(); if(tv->tv_usec < 0) { tv->tv_usec += 1000000; tv->tv_sec--; } xtime = *tv; time_adjust = 0; /* stop active adjtime() */ time_status |= STA_UNSYNC; time_maxerror = NTP_PHASE_LIMIT; time_esterror = NTP_PHASE_LIMIT; } /* * BUG: This routine does not handle hour overflow properly; it just * sets the minutes. Usually you won't notice until after reboot! */ static int set_rtc_mmss(unsigned long nowtime) { int real_seconds, real_minutes, mostek_minutes; struct mostek48t02 *regs = (struct mostek48t02 *)mstk48t02_regs; #ifdef CONFIG_SUN4 struct intersil *iregs = intersil_clock; int temp; #endif /* Not having a register set can lead to trouble. */ if (!regs) { #ifdef CONFIG_SUN4 if(!iregs) return -1; else { temp = iregs->clk.int_csec; mostek_minutes = iregs->clk.int_min; real_seconds = nowtime % 60; real_minutes = nowtime / 60; if (((abs(real_minutes - mostek_minutes) + 15)/30) & 1) real_minutes += 30; /* correct for half hour time zone */ real_minutes %= 60; if (abs(real_minutes - mostek_minutes) < 30) { intersil_stop(iregs); iregs->clk.int_sec=real_seconds; iregs->clk.int_min=real_minutes; intersil_start(iregs); } else { printk(KERN_WARNING "set_rtc_mmss: can't update from %d to %d\n", mostek_minutes, real_minutes); return -1; } return 0; } #endif } /* Read the current RTC minutes. */ regs->creg |= MSTK_CREG_READ; mostek_minutes = MSTK_REG_MIN(regs); regs->creg &= ~MSTK_CREG_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 - mostek_minutes) + 15)/30) & 1) real_minutes += 30; /* correct for half hour time zone */ real_minutes %= 60; if (abs(real_minutes - mostek_minutes) < 30) { regs->creg |= MSTK_CREG_WRITE; MSTK_SET_REG_SEC(regs,real_seconds); MSTK_SET_REG_MIN(regs,real_minutes); regs->creg &= ~MSTK_CREG_WRITE; } else return -1; return 0; }