/* * x86 TSC related functions */ #ifndef _ASM_X86_TSC_H #define _ASM_X86_TSC_H #include #define NS_SCALE 10 /* 2^10, carefully chosen */ #define US_SCALE 32 /* 2^32, arbitralrily chosen */ /* * Standard way to access the cycle counter. */ typedef unsigned long long cycles_t; extern unsigned int cpu_khz; extern unsigned int tsc_khz; extern void disable_TSC(void); static inline cycles_t get_cycles(void) { #ifndef CONFIG_X86_TSC if (!boot_cpu_has(X86_FEATURE_TSC)) return 0; #endif return rdtsc(); } extern struct system_counterval_t convert_art_to_tsc(cycle_t art); extern void tsc_init(void); extern void mark_tsc_unstable(char *reason); extern int unsynchronized_tsc(void); extern int check_tsc_unstable(void); extern int check_tsc_disabled(void); extern unsigned long native_calibrate_cpu(void); extern unsigned long native_calibrate_tsc(void); extern unsigned long long native_sched_clock_from_tsc(u64 tsc); extern int tsc_clocksource_reliable; /* * Boot-time check whether the TSCs are synchronized across * all CPUs/cores: */ extern void check_tsc_sync_source(int cpu); extern void check_tsc_sync_target(void); extern int notsc_setup(char *); extern void tsc_save_sched_clock_state(void); extern void tsc_restore_sched_clock_state(void); unsigned long cpu_khz_from_msr(void); #endif /* _ASM_X86_TSC_H */