diff options
| author | Dave Jones <davej@redhat.com> | 2005-05-31 19:03:46 -0700 |
|---|---|---|
| committer | Dave Jones <davej@redhat.com> | 2005-05-31 19:03:46 -0700 |
| commit | c5d28fb297efaa97c4b90e36f9dff3066e7f2778 (patch) | |
| tree | b0636983104860fa15d9054d29ec9e8b912642cd | |
| parent | 91350ed49bf3613e243c2e216228cd4ae8f32516 (diff) | |
[CPUFREQ] Recalibrate cpu_khz [2/2]
Some cpufreq drivers (at that time, only powernow-k7) need to recalibrate the
cpu_khz at runtime.
Signed-off-by: Bruno Ducrot <ducrot@poupinou.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dave Jones <davej@redhat.com>
| -rw-r--r-- | arch/i386/kernel/timers/common.c | 6 | ||||
| -rw-r--r-- | arch/i386/kernel/timers/timer_tsc.c | 20 | ||||
| -rw-r--r-- | include/asm-i386/timer.h | 1 |
3 files changed, 25 insertions, 2 deletions
diff --git a/arch/i386/kernel/timers/common.c b/arch/i386/kernel/timers/common.c index f7f90005e22e..8e201219f525 100644 --- a/arch/i386/kernel/timers/common.c +++ b/arch/i386/kernel/timers/common.c @@ -6,6 +6,7 @@ #include <linux/timex.h> #include <linux/errno.h> #include <linux/jiffies.h> +#include <linux/module.h> #include <asm/io.h> #include <asm/timer.h> @@ -24,7 +25,7 @@ #define CALIBRATE_TIME (5 * 1000020/HZ) -unsigned long __init calibrate_tsc(void) +unsigned long calibrate_tsc(void) { mach_prepare_counter(); @@ -139,7 +140,7 @@ bad_calibration: #endif /* calculate cpu_khz */ -void __init init_cpu_khz(void) +void init_cpu_khz(void) { if (cpu_has_tsc) { unsigned long tsc_quotient = calibrate_tsc(); @@ -158,3 +159,4 @@ void __init init_cpu_khz(void) } } } + diff --git a/arch/i386/kernel/timers/timer_tsc.c b/arch/i386/kernel/timers/timer_tsc.c index 7926d967be00..180444d87824 100644 --- a/arch/i386/kernel/timers/timer_tsc.c +++ b/arch/i386/kernel/timers/timer_tsc.c @@ -320,6 +320,26 @@ core_initcall(cpufreq_tsc); static inline void cpufreq_delayed_get(void) { return; } #endif +int recalibrate_cpu_khz(void) +{ +#ifndef CONFIG_SMP + unsigned long cpu_khz_old = cpu_khz; + + if (cpu_has_tsc) { + init_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); + static void mark_offset_tsc(void) { unsigned long lost,delay; diff --git a/include/asm-i386/timer.h b/include/asm-i386/timer.h index 40c54f69780e..c34709849839 100644 --- a/include/asm-i386/timer.h +++ b/include/asm-i386/timer.h @@ -53,6 +53,7 @@ extern struct init_timer_opts timer_cyclone_init; extern unsigned long calibrate_tsc(void); extern void init_cpu_khz(void); +extern int recalibrate_cpu_khz(void); #ifdef CONFIG_HPET_TIMER extern struct init_timer_opts timer_hpet_init; extern unsigned long calibrate_tsc_hpet(unsigned long *tsc_hpet_quotient_ptr); |