tsc.h (2016B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * x86 TSC related functions 4 */ 5#ifndef _ASM_X86_TSC_H 6#define _ASM_X86_TSC_H 7 8#include <asm/processor.h> 9#include <asm/cpufeature.h> 10 11/* 12 * Standard way to access the cycle counter. 13 */ 14typedef unsigned long long cycles_t; 15 16extern unsigned int cpu_khz; 17extern unsigned int tsc_khz; 18 19extern void disable_TSC(void); 20 21static inline cycles_t get_cycles(void) 22{ 23 if (!IS_ENABLED(CONFIG_X86_TSC) && 24 !cpu_feature_enabled(X86_FEATURE_TSC)) 25 return 0; 26 return rdtsc(); 27} 28#define get_cycles get_cycles 29 30extern struct system_counterval_t convert_art_to_tsc(u64 art); 31extern struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns); 32 33extern void tsc_early_init(void); 34extern void tsc_init(void); 35extern unsigned long calibrate_delay_is_known(void); 36extern void mark_tsc_unstable(char *reason); 37extern int unsynchronized_tsc(void); 38extern int check_tsc_unstable(void); 39extern void mark_tsc_async_resets(char *reason); 40extern unsigned long native_calibrate_cpu_early(void); 41extern unsigned long native_calibrate_tsc(void); 42extern unsigned long long native_sched_clock_from_tsc(u64 tsc); 43 44extern int tsc_clocksource_reliable; 45#ifdef CONFIG_X86_TSC 46extern bool tsc_async_resets; 47#else 48# define tsc_async_resets false 49#endif 50 51/* 52 * Boot-time check whether the TSCs are synchronized across 53 * all CPUs/cores: 54 */ 55#ifdef CONFIG_X86_TSC 56extern bool tsc_store_and_check_tsc_adjust(bool bootcpu); 57extern void tsc_verify_tsc_adjust(bool resume); 58extern void check_tsc_sync_source(int cpu); 59extern void check_tsc_sync_target(void); 60#else 61static inline bool tsc_store_and_check_tsc_adjust(bool bootcpu) { return false; } 62static inline void tsc_verify_tsc_adjust(bool resume) { } 63static inline void check_tsc_sync_source(int cpu) { } 64static inline void check_tsc_sync_target(void) { } 65#endif 66 67extern int notsc_setup(char *); 68extern void tsc_save_sched_clock_state(void); 69extern void tsc_restore_sched_clock_state(void); 70 71unsigned long cpu_khz_from_msr(void); 72 73#endif /* _ASM_X86_TSC_H */