diff options
Diffstat (limited to 'arch/sparc/kernel/time.c')
-rw-r--r-- | arch/sparc/kernel/time.c | 641 |
1 files changed, 641 insertions, 0 deletions
diff --git a/arch/sparc/kernel/time.c b/arch/sparc/kernel/time.c new file mode 100644 index 000000000000..6486cbf2efe9 --- /dev/null +++ b/arch/sparc/kernel/time.c @@ -0,0 +1,641 @@ +/* $Id: time.c,v 1.60 2002/01/23 14:33:55 davem 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 <linux/config.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/param.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/time.h> +#include <linux/timex.h> +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/ioport.h> +#include <linux/profile.h> + +#include <asm/oplib.h> +#include <asm/segment.h> +#include <asm/timer.h> +#include <asm/mostek.h> +#include <asm/system.h> +#include <asm/irq.h> +#include <asm/io.h> +#include <asm/idprom.h> +#include <asm/machines.h> +#include <asm/sun4paddr.h> +#include <asm/page.h> +#include <asm/pcic.h> + +extern unsigned long wall_jiffies; + +u64 jiffies_64 = INITIAL_JIFFIES; + +EXPORT_SYMBOL(jiffies_64); + +DEFINE_SPINLOCK(rtc_lock); +enum sparc_clock_type sp_clock_typ; +DEFINE_SPINLOCK(mostek_lock); +void __iomem *mstk48t02_regs = NULL; +static struct mostek48t08 *mstk48t08_regs = NULL; +static int set_rtc_mmss(unsigned long); +static int sbus_do_settimeofday(struct timespec *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 + +unsigned long profile_pc(struct pt_regs *regs) +{ + extern char __copy_user_begin[], __copy_user_end[]; + extern char __atomic_begin[], __atomic_end[]; + extern char __bzero_begin[], __bzero_end[]; + extern char __bitops_begin[], __bitops_end[]; + + unsigned long pc = regs->pc; + + if (in_lock_functions(pc) || + (pc >= (unsigned long) __copy_user_begin && + pc < (unsigned long) __copy_user_end) || + (pc >= (unsigned long) __atomic_begin && + pc < (unsigned long) __atomic_end) || + (pc >= (unsigned long) __bzero_begin && + pc < (unsigned long) __bzero_end) || + (pc >= (unsigned long) __bitops_begin && + pc < (unsigned long) __bitops_end)) + pc = regs->u_regs[UREG_RETPC]; + return pc; +} + +__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 + */ + +#define TICK_SIZE (tick_nsec / 1000) + +irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs * regs) +{ + /* last time the cmos clock got updated */ + static long last_rtc_update; + +#ifndef CONFIG_SMP + profile_tick(CPU_PROFILING, regs); +#endif + + /* Protect counter clear so that do_gettimeoffset works */ + write_seqlock(&xtime_lock); +#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(); + + do_timer(regs); +#ifndef CONFIG_SMP + update_process_times(user_mode(regs)); +#endif + + + /* Determine when to update the Mostek clock. */ + if ((time_status & STA_UNSYNC) == 0 && + xtime.tv_sec > last_rtc_update + 660 && + (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && + (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 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_sequnlock(&xtime_lock); + + return IRQ_HANDLED; +} + +/* 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 "); + + spin_lock_irq(&mostek_lock); + + /* 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; + + spin_unlock_irq(&mostek_lock); + + /* 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"); + + spin_lock_irq(&mostek_lock); + + /* 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; + + spin_unlock_irq(&mostek_lock); + + /* 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"); + + spin_lock_irq(&mostek_lock); + regs->creg |= MSTK_CREG_WRITE; + regs->hour &= ~MSTK_KICK_START; + regs->creg &= ~MSTK_CREG_WRITE; + spin_unlock_irq(&mostek_lock); + } + + 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; + + spin_lock_irq(&mostek_lock); + 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. */ + spin_unlock_irq(&mostek_lock); + + 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), NULL); + mstk48t08_regs = NULL; /* To catch weirdness */ + intersil_clock = NULL; /* 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 = NULL; /* 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 = NULL; /* 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 = &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 + + BTFIXUPSET_CALL(bus_do_settimeofday, sbus_do_settimeofday, BTFIXUPCALL_NORM); + btfixup(); + + if (ARCH_SUN4) + sun4_clock_probe(); + else + clock_probe(); + + sparc_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(); + } + spin_lock_irq(&mostek_lock); + 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_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ); + set_normalized_timespec(&wall_to_monotonic, + -xtime.tv_sec, -xtime.tv_nsec); + mregs->creg &= ~MSTK_CREG_READ; + spin_unlock_irq(&mostek_lock); +#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_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ); + set_normalized_timespec(&wall_to_monotonic, + -xtime.tv_sec, -xtime.tv_nsec); + 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. */ + local_irq_enable(); +} + +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) +{ + return (*master_l10_counter >> 10) & 0x1fffff; +} + +/* + * Returns nanoseconds + * XXX This is a suboptimal implementation. + */ +unsigned long long sched_clock(void) +{ + return (unsigned long long)jiffies * (1000000000 / HZ); +} + +/* Ok, my cute asm atomicity trick doesn't work anymore. + * There are just too many variables that need to be protected + * now (both members of xtime, wall_jiffies, et al.) + */ +void do_gettimeofday(struct timeval *tv) +{ + unsigned long flags; + unsigned long seq; + unsigned long usec, sec; + unsigned long max_ntp_tick = tick_usec - tickadj; + + do { + unsigned long lost; + + seq = read_seqbegin_irqsave(&xtime_lock, flags); + usec = do_gettimeoffset(); + lost = jiffies - wall_jiffies; + + /* + * If time_adjust is negative then NTP is slowing the clock + * so make sure not to go into next possible interval. + * Better to lose some accuracy than have time go backwards.. + */ + if (unlikely(time_adjust < 0)) { + usec = min(usec, max_ntp_tick); + + if (lost) + usec += lost * max_ntp_tick; + } + else if (unlikely(lost)) + usec += lost * tick_usec; + + sec = xtime.tv_sec; + usec += (xtime.tv_nsec / 1000); + } 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) +{ + int ret; + + write_seqlock_irq(&xtime_lock); + ret = bus_do_settimeofday(tv); + write_sequnlock_irq(&xtime_lock); + clock_was_set(); + return ret; +} + +EXPORT_SYMBOL(do_settimeofday); + +static int sbus_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; + + /* + * This is revolting. We need to set "xtime" correctly. However, the + * value in this location is the value at the most recent update of + * wall time. Discover what correction gettimeofday() would have + * made, and then undo it! + */ + nsec -= 1000 * (do_gettimeoffset() + + (jiffies - wall_jiffies) * (USEC_PER_SEC / HZ)); + + 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); + + time_adjust = 0; /* stop active adjtime() */ + time_status |= STA_UNSYNC; + time_maxerror = NTP_PHASE_LIMIT; + time_esterror = NTP_PHASE_LIMIT; + return 0; +} + +/* + * 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; + unsigned long flags; +#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 + } + + spin_lock_irqsave(&mostek_lock, flags); + /* 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; + spin_unlock_irqrestore(&mostek_lock, flags); + return 0; + } else { + spin_unlock_irqrestore(&mostek_lock, flags); + return -1; + } +} |