diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/i386/Kconfig | 4 | ||||
| -rw-r--r-- | arch/i386/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/i386/kernel/time.c | 153 | ||||
| -rw-r--r-- | arch/i386/kernel/tsc.c | 3 | ||||
| -rw-r--r-- | arch/i386/lib/delay.c | 65 |
5 files changed, 82 insertions, 144 deletions
diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index 1596101cfaf..db1f8b40606 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -14,6 +14,10 @@ config X86_32 486, 586, Pentiums, and various instruction-set-compatible chips by AMD, Cyrix, and others. +config GENERIC_TIME + bool + default y + config SEMAPHORE_SLEEPERS bool default y diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile index ca70d61ea83..f238cb6274e 100644 --- a/arch/i386/kernel/Makefile +++ b/arch/i386/kernel/Makefile @@ -10,7 +10,6 @@ obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o \ quirks.o i8237.o topology.o alternative.o i8253.o tsc.o obj-y += cpu/ -obj-y += timers/ obj-y += acpi/ obj-$(CONFIG_X86_BIOS_REBOOT) += reboot.o obj-$(CONFIG_MCA) += mca.o diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index 796e5faa6ca..2a6ab86ffc1 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -82,7 +82,8 @@ extern unsigned long wall_jiffies; DEFINE_SPINLOCK(rtc_lock); EXPORT_SYMBOL(rtc_lock); -struct timer_opts *cur_timer __read_mostly = &timer_none; +/* XXX - necessary to keep things compiling. to be removed later */ +u32 pmtmr_ioport; /* * This is a special lock that is owned by the CPU and holds the index @@ -113,99 +114,19 @@ void rtc_cmos_write(unsigned char val, unsigned char addr) } EXPORT_SYMBOL(rtc_cmos_write); -/* - * This version of gettimeofday has microsecond resolution - * and better than microsecond precision on fast x86 machines with TSC. - */ -void do_gettimeofday(struct timeval *tv) -{ - unsigned long seq; - unsigned long usec, sec; - unsigned long max_ntp_tick; - - do { - unsigned long lost; - - seq = read_seqbegin(&xtime_lock); - - usec = cur_timer->get_offset(); - 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)) { - max_ntp_tick = (USEC_PER_SEC / HZ) - tickadj; - usec = min(usec, max_ntp_tick); - - if (lost) - usec += lost * max_ntp_tick; - } - else if (unlikely(lost)) - usec += lost * (USEC_PER_SEC / HZ); - - sec = xtime.tv_sec; - usec += (xtime.tv_nsec / 1000); - } while (read_seqretry(&xtime_lock, seq)); - - while (usec >= 1000000) { - usec -= 1000000; - sec++; - } - - tv->tv_sec = sec; - tv->tv_usec = usec; -} - -EXPORT_SYMBOL(do_gettimeofday); - -int 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; - - write_seqlock_irq(&xtime_lock); - /* - * 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 -= cur_timer->get_offset() * NSEC_PER_USEC; - nsec -= (jiffies - wall_jiffies) * TICK_NSEC; - - 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); - - ntp_clear(); - write_sequnlock_irq(&xtime_lock); - clock_was_set(); - return 0; -} - -EXPORT_SYMBOL(do_settimeofday); - static int set_rtc_mmss(unsigned long nowtime) { int retval; - - WARN_ON(irqs_disabled()); + unsigned long flags; /* gets recalled with irq locally disabled */ - spin_lock_irq(&rtc_lock); + /* XXX - does irqsave resolve this? -johnstul */ + spin_lock_irqsave(&rtc_lock, flags); if (efi_enabled) retval = efi_set_rtc_mmss(nowtime); else retval = mach_set_rtc_mmss(nowtime); - spin_unlock_irq(&rtc_lock); + spin_unlock_irqrestore(&rtc_lock, flags); return retval; } @@ -213,16 +134,6 @@ static int set_rtc_mmss(unsigned long nowtime) int timer_ack; -/* monotonic_clock(): returns # of nanoseconds passed since time_init() - * Note: This function is required to return accurate - * time even in the absence of multiple timer ticks. - */ -unsigned long long monotonic_clock(void) -{ - return cur_timer->monotonic_clock(); -} -EXPORT_SYMBOL(monotonic_clock); - #if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER) unsigned long profile_pc(struct pt_regs *regs) { @@ -237,11 +148,21 @@ EXPORT_SYMBOL(profile_pc); #endif /* - * timer_interrupt() needs to keep up the real-time clock, - * as well as call the "do_timer()" routine every clocktick + * This is the same as the above, except we _also_ save the current + * Time Stamp Counter value at the time of the timer interrupt, so that + * we later on can estimate the time of day more exactly. */ -static inline void do_timer_interrupt(int irq, struct pt_regs *regs) +irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) { + /* + * Here we are in the timer irq handler. We just have irqs locally + * disabled but we don't know if the timer_bh is running on the other + * CPU. We need to avoid to SMP race with it. NOTE: we don' t need + * the irq version of write_lock because as just said we have irq + * locally disabled. -arca + */ + write_seqlock(&xtime_lock); + #ifdef CONFIG_X86_IO_APIC if (timer_ack) { /* @@ -274,27 +195,6 @@ static inline void do_timer_interrupt(int irq, struct pt_regs *regs) irq = inb_p( 0x61 ); /* read the current state */ outb_p( irq|0x80, 0x61 ); /* reset the IRQ */ } -} - -/* - * This is the same as the above, except we _also_ save the current - * Time Stamp Counter value at the time of the timer interrupt, so that - * we later on can estimate the time of day more exactly. - */ -irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) -{ - /* - * Here we are in the timer irq handler. We just have irqs locally - * disabled but we don't know if the timer_bh is running on the other - * CPU. We need to avoid to SMP race with it. NOTE: we don' t need - * the irq version of write_lock because as just said we have irq - * locally disabled. -arca - */ - write_seqlock(&xtime_lock); - - cur_timer->mark_offset(); - - do_timer_interrupt(irq, regs); write_sequnlock(&xtime_lock); @@ -375,7 +275,6 @@ void notify_arch_cmos_timer(void) static long clock_cmos_diff, sleep_start; -static struct timer_opts *last_timer; static int timer_suspend(struct sys_device *dev, pm_message_t state) { /* @@ -384,10 +283,6 @@ static int timer_suspend(struct sys_device *dev, pm_message_t state) clock_cmos_diff = -get_cmos_time(); clock_cmos_diff += get_seconds(); sleep_start = get_cmos_time(); - last_timer = cur_timer; - cur_timer = &timer_none; - if (last_timer->suspend) - last_timer->suspend(state); return 0; } @@ -410,10 +305,6 @@ static int timer_resume(struct sys_device *dev) jiffies_64 += sleep_length; wall_jiffies += sleep_length; write_sequnlock_irqrestore(&xtime_lock, flags); - if (last_timer->resume) - last_timer->resume(); - cur_timer = last_timer; - last_timer = NULL; touch_softlockup_watchdog(); return 0; } @@ -455,9 +346,6 @@ static void __init hpet_time_init(void) printk("Using HPET for base-timer\n"); } - cur_timer = select_timer(); - printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name); - time_init_hook(); } #endif @@ -479,8 +367,5 @@ void __init time_init(void) set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); - cur_timer = select_timer(); - printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name); - time_init_hook(); } diff --git a/arch/i386/kernel/tsc.c b/arch/i386/kernel/tsc.c index 3b64eaafce2..96b307495e5 100644 --- a/arch/i386/kernel/tsc.c +++ b/arch/i386/kernel/tsc.c @@ -10,6 +10,7 @@ #include <linux/init.h> #include <asm/tsc.h> +#include <asm/delay.h> #include <asm/io.h> #include "mach_timer.h" @@ -45,7 +46,6 @@ static int __init tsc_setup(char *str) __setup("notsc", tsc_setup); - /* * code to mark and check if the TSC is unstable * due to cpufreq or due to unsynced TSCs @@ -205,6 +205,7 @@ void tsc_init(void) (unsigned long)cpu_khz % 1000); set_cyc2ns_scale(cpu_khz); + use_tsc_delay(); } #ifdef CONFIG_CPU_FREQ diff --git a/arch/i386/lib/delay.c b/arch/i386/lib/delay.c index c49a6acbee5..3c0714c4b66 100644 --- a/arch/i386/lib/delay.c +++ b/arch/i386/lib/delay.c @@ -10,43 +10,92 @@ * we have to worry about. */ +#include <linux/module.h> #include <linux/config.h> #include <linux/sched.h> #include <linux/delay.h> -#include <linux/module.h> + #include <asm/processor.h> #include <asm/delay.h> #include <asm/timer.h> #ifdef CONFIG_SMP -#include <asm/smp.h> +# include <asm/smp.h> #endif -extern struct timer_opts* timer; +/* simple loop based delay: */ +static void delay_loop(unsigned long loops) +{ + int d0; + + __asm__ __volatile__( + "\tjmp 1f\n" + ".align 16\n" + "1:\tjmp 2f\n" + ".align 16\n" + "2:\tdecl %0\n\tjns 2b" + :"=&a" (d0) + :"0" (loops)); +} + +/* TSC based delay: */ +static void delay_tsc(unsigned long loops) +{ + unsigned long bclock, now; + + rdtscl(bclock); + do { + rep_nop(); + rdtscl(now); + } while ((now-bclock) < loops); +} + +/* + * Since we calibrate only once at boot, this + * function should be set once at boot and not changed + */ +static void (*delay_fn)(unsigned long) = delay_loop; + +void use_tsc_delay(void) +{ + delay_fn = delay_tsc; +} + +int read_current_timer(unsigned long *timer_val) +{ + if (delay_fn == delay_tsc) { + rdtscl(*timer_val); + return 0; + } + return -1; +} void __delay(unsigned long loops) { - cur_timer->delay(loops); + delay_fn(loops); } inline void __const_udelay(unsigned long xloops) { int d0; + xloops *= 4; __asm__("mull %0" :"=d" (xloops), "=&a" (d0) - :"1" (xloops),"0" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))); - __delay(++xloops); + :"1" (xloops), "0" + (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))); + + __delay(++xloops); } void __udelay(unsigned long usecs) { - __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */ + __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */ } void __ndelay(unsigned long nsecs) { - __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */ + __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */ } EXPORT_SYMBOL(__delay); |