diff options
| -rw-r--r-- | arch/x86/kernel/time_64.c | 26 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc.c | 131 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc_32.c | 74 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc_64.c | 94 | ||||
| -rw-r--r-- | include/asm-x86/hpet.h | 2 | ||||
| -rw-r--r-- | include/asm-x86/tsc.h | 1 |
6 files changed, 154 insertions, 174 deletions
diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c index 39ae8511a13..c6ac4dad41f 100644 --- a/arch/x86/kernel/time_64.c +++ b/arch/x86/kernel/time_64.c @@ -56,7 +56,7 @@ static irqreturn_t timer_event_interrupt(int irq, void *dev_id) /* calibrate_cpu is used on systems with fixed rate TSCs to determine * processor frequency */ #define TICK_COUNT 100000000 -unsigned long __init native_calculate_cpu_khz(void) +static unsigned long __init calibrate_cpu(void) { int tsc_start, tsc_now; int i, no_ctr_free; @@ -114,14 +114,18 @@ void __init hpet_time_init(void) setup_irq(0, &irq0); } +extern void set_cyc2ns_scale(unsigned long cpu_khz, int cpu); + void __init time_init(void) { - tsc_calibrate(); + int cpu; + + cpu_khz = calculate_cpu_khz(); + tsc_khz = cpu_khz; - cpu_khz = tsc_khz; if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) && - (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)) - cpu_khz = calculate_cpu_khz(); + (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)) + cpu_khz = calibrate_cpu(); lpj_fine = ((unsigned long)tsc_khz * 1000)/HZ; @@ -134,7 +138,17 @@ void __init time_init(void) vgetcpu_mode = VGETCPU_LSL; printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n", - cpu_khz / 1000, cpu_khz % 1000); + cpu_khz / 1000, cpu_khz % 1000); + + /* + * Secondary CPUs do not run through tsc_init(), so set up + * all the scale factors for all CPUs, assuming the same + * speed as the bootup CPU. (cpufreq notifiers will fix this + * up if their speed diverges) + */ + for_each_possible_cpu(cpu) + set_cyc2ns_scale(cpu_khz, cpu); + init_tsc_clocksource(); late_time_init = choose_time_init(); } diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 5d0be778fad..e6ee14533c7 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1,7 +1,11 @@ +#include <linux/kernel.h> #include <linux/sched.h> #include <linux/init.h> #include <linux/module.h> #include <linux/timer.h> +#include <linux/acpi_pmtmr.h> + +#include <asm/hpet.h> unsigned int cpu_khz; /* TSC clocks / usec, not used here */ EXPORT_SYMBOL(cpu_khz); @@ -84,3 +88,130 @@ int __init notsc_setup(char *str) #endif __setup("notsc", notsc_setup); + +#define MAX_RETRIES 5 +#define SMI_TRESHOLD 50000 + +/* + * Read TSC and the reference counters. Take care of SMI disturbance + */ +static u64 __init tsc_read_refs(u64 *pm, u64 *hpet) +{ + u64 t1, t2; + int i; + + for (i = 0; i < MAX_RETRIES; i++) { + t1 = get_cycles(); + if (hpet) + *hpet = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF; + else + *pm = acpi_pm_read_early(); + t2 = get_cycles(); + if ((t2 - t1) < SMI_TRESHOLD) + return t2; + } + return ULLONG_MAX; +} + +/** + * tsc_calibrate - calibrate the tsc on boot + */ +static unsigned int __init tsc_calibrate(void) +{ + unsigned long flags; + u64 tsc1, tsc2, tr1, tr2, delta, pm1, pm2, hpet1, hpet2; + int hpet = is_hpet_enabled(); + unsigned int tsc_khz_val = 0; + + local_irq_save(flags); + + tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL); + + outb((inb(0x61) & ~0x02) | 0x01, 0x61); + + outb(0xb0, 0x43); + outb((CLOCK_TICK_RATE / (1000 / 50)) & 0xff, 0x42); + outb((CLOCK_TICK_RATE / (1000 / 50)) >> 8, 0x42); + tr1 = get_cycles(); + while ((inb(0x61) & 0x20) == 0); + tr2 = get_cycles(); + + tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL); + + local_irq_restore(flags); + + /* + * Preset the result with the raw and inaccurate PIT + * calibration value + */ + delta = (tr2 - tr1); + do_div(delta, 50); + tsc_khz_val = delta; + + /* hpet or pmtimer available ? */ + if (!hpet && !pm1 && !pm2) { + printk(KERN_INFO "TSC calibrated against PIT\n"); + goto out; + } + + /* Check, whether the sampling was disturbed by an SMI */ + if (tsc1 == ULLONG_MAX || tsc2 == ULLONG_MAX) { + printk(KERN_WARNING "TSC calibration disturbed by SMI, " + "using PIT calibration result\n"); + goto out; + } + + tsc2 = (tsc2 - tsc1) * 1000000LL; + + if (hpet) { + printk(KERN_INFO "TSC calibrated against HPET\n"); + if (hpet2 < hpet1) + hpet2 += 0x100000000ULL; + hpet2 -= hpet1; + tsc1 = ((u64)hpet2 * hpet_readl(HPET_PERIOD)); + do_div(tsc1, 1000000); + } else { + printk(KERN_INFO "TSC calibrated against PM_TIMER\n"); + if (pm2 < pm1) + pm2 += (u64)ACPI_PM_OVRRUN; + pm2 -= pm1; + tsc1 = pm2 * 1000000000LL; + do_div(tsc1, PMTMR_TICKS_PER_SEC); + } + + do_div(tsc2, tsc1); + tsc_khz_val = tsc2; + +out: + return tsc_khz_val; +} + +unsigned long native_calculate_cpu_khz(void) +{ + return tsc_calibrate(); +} + +#ifdef CONFIG_X86_32 +/* Only called from the Powernow K7 cpu freq driver */ +int recalibrate_cpu_khz(void) +{ +#ifndef CONFIG_SMP + unsigned long cpu_khz_old = cpu_khz; + + if (cpu_has_tsc) { + cpu_khz = calculate_cpu_khz(); + tsc_khz = cpu_khz; + cpu_data(0).loops_per_jiffy = + cpufreq_scale(cpu_data(0).loops_per_jiffy, + cpu_khz_old, cpu_khz); + return 0; + } else + return -ENODEV; +#else + return -ENODEV; +#endif +} + +EXPORT_SYMBOL(recalibrate_cpu_khz); + +#endif /* CONFIG_X86_32 */ diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c index dc8990056d7..40c0aafb358 100644 --- a/arch/x86/kernel/tsc_32.c +++ b/arch/x86/kernel/tsc_32.c @@ -42,7 +42,7 @@ extern int tsc_disabled; DEFINE_PER_CPU(unsigned long, cyc2ns); -static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) +void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) { unsigned long long tsc_now, ns_now; unsigned long flags, *scale; @@ -65,78 +65,6 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) local_irq_restore(flags); } -unsigned long native_calculate_cpu_khz(void) -{ - unsigned long long start, end; - unsigned long count; - u64 delta64 = (u64)ULLONG_MAX; - int i; - unsigned long flags; - - local_irq_save(flags); - - /* run 3 times to ensure the cache is warm and to get an accurate reading */ - for (i = 0; i < 3; i++) { - mach_prepare_counter(); - rdtscll(start); - mach_countup(&count); - rdtscll(end); - - /* - * Error: ECTCNEVERSET - * The CTC wasn't reliable: we got a hit on the very first read, - * or the CPU was so fast/slow that the quotient wouldn't fit in - * 32 bits.. - */ - if (count <= 1) - continue; - - /* cpu freq too slow: */ - if ((end - start) <= CALIBRATE_TIME_MSEC) - continue; - - /* - * We want the minimum time of all runs in case one of them - * is inaccurate due to SMI or other delay - */ - delta64 = min(delta64, (end - start)); - } - - /* cpu freq too fast (or every run was bad): */ - if (delta64 > (1ULL<<32)) - goto err; - - delta64 += CALIBRATE_TIME_MSEC/2; /* round for do_div */ - do_div(delta64,CALIBRATE_TIME_MSEC); - - local_irq_restore(flags); - return (unsigned long)delta64; -err: - local_irq_restore(flags); - return 0; -} - -int recalibrate_cpu_khz(void) -{ -#ifndef CONFIG_SMP - unsigned long cpu_khz_old = cpu_khz; - - if (cpu_has_tsc) { - cpu_khz = calculate_cpu_khz(); - tsc_khz = cpu_khz; - cpu_data(0).loops_per_jiffy = - cpufreq_scale(cpu_data(0).loops_per_jiffy, - cpu_khz_old, cpu_khz); - return 0; - } else - return -ENODEV; -#else - return -ENODEV; -#endif -} - -EXPORT_SYMBOL(recalibrate_cpu_khz); - #ifdef CONFIG_CPU_FREQ /* diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c index 69cbe4c9f05..c852ff9bd5d 100644 --- a/arch/x86/kernel/tsc_64.c +++ b/arch/x86/kernel/tsc_64.c @@ -40,7 +40,7 @@ extern int tsc_disabled; DEFINE_PER_CPU(unsigned long, cyc2ns); -static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) +void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) { unsigned long long tsc_now, ns_now; unsigned long flags, *scale; @@ -130,98 +130,6 @@ core_initcall(cpufreq_tsc); #endif -#define MAX_RETRIES 5 -#define SMI_TRESHOLD 50000 - -/* - * Read TSC and the reference counters. Take care of SMI disturbance - */ -static unsigned long __init tsc_read_refs(unsigned long *pm, - unsigned long *hpet) -{ - unsigned long t1, t2; - int i; - - for (i = 0; i < MAX_RETRIES; i++) { - t1 = get_cycles(); - if (hpet) - *hpet = hpet_readl(HPET_COUNTER) & 0xFFFFFFFF; - else - *pm = acpi_pm_read_early(); - t2 = get_cycles(); - if ((t2 - t1) < SMI_TRESHOLD) - return t2; - } - return ULONG_MAX; -} - -/** - * tsc_calibrate - calibrate the tsc on boot - */ -void __init tsc_calibrate(void) -{ - unsigned long flags, tsc1, tsc2, tr1, tr2, pm1, pm2, hpet1, hpet2; - int hpet = is_hpet_enabled(), cpu; - - local_irq_save(flags); - - tsc1 = tsc_read_refs(&pm1, hpet ? &hpet1 : NULL); - - outb((inb(0x61) & ~0x02) | 0x01, 0x61); - - outb(0xb0, 0x43); - outb((CLOCK_TICK_RATE / (1000 / 50)) & 0xff, 0x42); - outb((CLOCK_TICK_RATE / (1000 / 50)) >> 8, 0x42); - tr1 = get_cycles(); - while ((inb(0x61) & 0x20) == 0); - tr2 = get_cycles(); - - tsc2 = tsc_read_refs(&pm2, hpet ? &hpet2 : NULL); - - local_irq_restore(flags); - - /* - * Preset the result with the raw and inaccurate PIT - * calibration value - */ - tsc_khz = (tr2 - tr1) / 50; - - /* hpet or pmtimer available ? */ - if (!hpet && !pm1 && !pm2) { - printk(KERN_INFO "TSC calibrated against PIT\n"); - goto out; - } - - /* Check, whether the sampling was disturbed by an SMI */ - if (tsc1 == ULONG_MAX || tsc2 == ULONG_MAX) { - printk(KERN_WARNING "TSC calibration disturbed by SMI, " - "using PIT calibration result\n"); - goto out; - } - - tsc2 = (tsc2 - tsc1) * 1000000L; - - if (hpet) { - printk(KERN_INFO "TSC calibrated against HPET\n"); - if (hpet2 < hpet1) - hpet2 += 0x100000000UL; - hpet2 -= hpet1; - tsc1 = (hpet2 * hpet_readl(HPET_PERIOD)) / 1000000; - } else { - printk(KERN_INFO "TSC calibrated against PM_TIMER\n"); - if (pm2 < pm1) - pm2 += ACPI_PM_OVRRUN; - pm2 -= pm1; - tsc1 = (pm2 * 1000000000) / PMTMR_TICKS_PER_SEC; - } - - tsc_khz = tsc2 / tsc1; - -out: - for_each_possible_cpu(cpu) - set_cyc2ns_scale(tsc_khz, cpu); -} - /* * Make an educated guess if the TSC is trustworthy and synchronized * over all CPUs. diff --git a/include/asm-x86/hpet.h b/include/asm-x86/hpet.h index 6a9b4ac59bf..82f1ac641bd 100644 --- a/include/asm-x86/hpet.h +++ b/include/asm-x86/hpet.h @@ -86,8 +86,8 @@ extern void hpet_unregister_irq_handler(rtc_irq_handler handler); #else /* CONFIG_HPET_TIMER */ static inline int hpet_enable(void) { return 0; } -static inline unsigned long hpet_readl(unsigned long a) { return 0; } static inline int is_hpet_enabled(void) { return 0; } +#define hpet_readl(a) 0 #endif #endif /* ASM_X86_HPET_H */ diff --git a/include/asm-x86/tsc.h b/include/asm-x86/tsc.h index 548873ab5fc..761054d7fef 100644 --- a/include/asm-x86/tsc.h +++ b/include/asm-x86/tsc.h @@ -58,7 +58,6 @@ int check_tsc_unstable(void); extern void check_tsc_sync_source(int cpu); extern void check_tsc_sync_target(void); -extern void tsc_calibrate(void); extern int notsc_setup(char *); #endif |