[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>
diff --git a/arch/i386/kernel/timers/common.c b/arch/i386/kernel/timers/common.c
index f7f9000..8e20121 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 @@
#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 @@
}
}
}
+
diff --git a/arch/i386/kernel/timers/timer_tsc.c b/arch/i386/kernel/timers/timer_tsc.c
index 7926d96..180444d 100644
--- a/arch/i386/kernel/timers/timer_tsc.c
+++ b/arch/i386/kernel/timers/timer_tsc.c
@@ -320,6 +320,26 @@
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 40c54f6..c347098 100644
--- a/include/asm-i386/timer.h
+++ b/include/asm-i386/timer.h
@@ -53,6 +53,7 @@
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);