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/*
* Copytight (C) 1999, 2000 Ralf Baechle (ralf@gnu.org)
* Copytight (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/param.h>
#include <linux/timex.h>
#include <linux/mm.h>
#include <asm/pgtable.h>
#include <asm/sgialib.h>
#include <asm/sn/ioc3.h>
#include <asm/m48t35.h>
#include <asm/sn/klconfig.h>
#include <asm/sn/arch.h>
#include <asm/sn/addrs.h>
#include <asm/sn/sn_private.h>
#include <asm/sn/sn0/ip27.h>
#include <asm/sn/sn0/hub.h>
/*
* 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[NR_CPUS]; /* What counter should be at next timer irq */
static long last_rtc_update; /* Last time the rtc clock got updated */
extern rwlock_t xtime_lock;
extern volatile unsigned long wall_jiffies;
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 cpuA = ((cputoslice(cpu)) == 0);
int irq = 7; /* XXX Assign number */
write_lock(&xtime_lock);
again:
LOCAL_HUB_S(cpuA ? PI_RT_PEND_A : PI_RT_PEND_B, 0); /* Ack */
ct_cur[cpu] += CYCLES_PER_JIFFY;
LOCAL_HUB_S(cpuA ? PI_RT_COMPARE_A : PI_RT_COMPARE_B, ct_cur[cpu]);
if (LOCAL_HUB_L(PI_RT_COUNT) >= ct_cur[cpu])
goto again;
kstat.irqs[cpu][irq]++; /* kstat only for bootcpu? */
if (cpu == 0)
do_timer(regs);
#ifdef CONFIG_SMP
{
int user = user_mode(regs);
/*
* update_process_times() expects us to have done irq_enter().
* Besides, if we don't timer interrupts ignore the global
* interrupt lock, which is the WrongThing (tm) to do.
* Picked from i386 code.
*/
irq_enter(cpu, 0);
update_process_times(user);
irq_exit(cpu, 0);
}
#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);
if (softirq_pending(cpu))
do_softirq();
}
unsigned long inline do_gettimeoffset(void)
{
unsigned long ct_cur1;
ct_cur1 = REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT) + CYCLES_PER_JIFFY;
return (ct_cur1 - ct_cur[0]) * NSEC_PER_CYCLE / 1000;
}
void do_gettimeofday(struct timeval *tv)
{
unsigned long flags;
unsigned long usec, sec;
read_lock_irqsave(&xtime_lock, flags);
usec = do_gettimeoffset();
{
unsigned long lost = jiffies - wall_jiffies;
if (lost)
usec += lost * (1000000 / HZ);
}
sec = xtime.tv_sec;
usec += xtime.tv_usec;
read_unlock_irqrestore(&xtime_lock, flags);
while (usec >= 1000000) {
usec -= 1000000;
sec++;
}
tv->tv_sec = sec;
tv->tv_usec = usec;
}
void do_settimeofday(struct timeval *tv)
{
write_lock_irq(&xtime_lock);
tv->tv_usec -= do_gettimeoffset();
tv->tv_usec -= (jiffies - wall_jiffies) * (1000000 / HZ);
while (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;
write_unlock_irq(&xtime_lock);
}
/* Includes for ioc3_init(). */
#include <asm/sn/types.h>
#include <asm/sn/sn0/addrs.h>
#include <asm/sn/sn0/hubni.h>
#include <asm/sn/sn0/hubio.h>
#include <asm/pci/bridge.h>
static __init unsigned long 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);
}
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", smp_processor_id(), 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) {
int cpu = smp_processor_id();
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[cpu] = CYCLES_PER_JIFFY;
LOCAL_HUB_S(PI_RT_COMPARE_A, ct_cur[cpu]);
LOCAL_HUB_S(PI_RT_COUNT, 0);
LOCAL_HUB_S(PI_RT_PEND_A, 0);
LOCAL_HUB_S(PI_RT_COMPARE_B, ct_cur[cpu]);
LOCAL_HUB_S(PI_RT_COUNT, 0);
LOCAL_HUB_S(PI_RT_PEND_B, 0);
}
}
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