1 /* 2 * include/asm-s390/timex.h 3 * 4 * S390 version 5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * 7 * Derived from "include/asm-i386/timex.h" 8 * Copyright (C) 1992, Linus Torvalds 9 */ 10 11 #ifndef _ASM_S390_TIMEX_H 12 #define _ASM_S390_TIMEX_H 13 14 #include <asm/lowcore.h> 15 16 /* The value of the TOD clock for 1.1.1970. */ 17 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL 18 19 /* Inline functions for clock register access. */ 20 static inline int set_clock(__u64 time) 21 { 22 int cc; 23 24 asm volatile( 25 " sck %1\n" 26 " ipm %0\n" 27 " srl %0,28\n" 28 : "=d" (cc) : "Q" (time) : "cc"); 29 return cc; 30 } 31 32 static inline int store_clock(__u64 *time) 33 { 34 int cc; 35 36 asm volatile( 37 " stck %1\n" 38 " ipm %0\n" 39 " srl %0,28\n" 40 : "=d" (cc), "=Q" (*time) : : "cc"); 41 return cc; 42 } 43 44 static inline void set_clock_comparator(__u64 time) 45 { 46 asm volatile("sckc %0" : : "Q" (time)); 47 } 48 49 static inline void store_clock_comparator(__u64 *time) 50 { 51 asm volatile("stckc %0" : "=Q" (*time)); 52 } 53 54 void clock_comparator_work(void); 55 56 static inline unsigned long long local_tick_disable(void) 57 { 58 unsigned long long old; 59 60 old = S390_lowcore.clock_comparator; 61 S390_lowcore.clock_comparator = -1ULL; 62 set_clock_comparator(S390_lowcore.clock_comparator); 63 return old; 64 } 65 66 static inline void local_tick_enable(unsigned long long comp) 67 { 68 S390_lowcore.clock_comparator = comp; 69 set_clock_comparator(S390_lowcore.clock_comparator); 70 } 71 72 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ 73 74 typedef unsigned long long cycles_t; 75 76 static inline unsigned long long get_clock(void) 77 { 78 unsigned long long clk; 79 80 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 81 asm volatile(".insn s,0xb27c0000,%0" : "=Q" (clk) : : "cc"); 82 #else 83 asm volatile("stck %0" : "=Q" (clk) : : "cc"); 84 #endif 85 return clk; 86 } 87 88 static inline void get_clock_ext(char *clk) 89 { 90 asm volatile("stcke %0" : "=Q" (*clk) : : "cc"); 91 } 92 93 static inline unsigned long long get_clock_xt(void) 94 { 95 unsigned char clk[16]; 96 get_clock_ext(clk); 97 return *((unsigned long long *)&clk[1]); 98 } 99 100 static inline cycles_t get_cycles(void) 101 { 102 return (cycles_t) get_clock() >> 2; 103 } 104 105 int get_sync_clock(unsigned long long *clock); 106 void init_cpu_timer(void); 107 unsigned long long monotonic_clock(void); 108 109 void tod_to_timeval(__u64, struct timespec *); 110 111 static inline 112 void stck_to_timespec(unsigned long long stck, struct timespec *ts) 113 { 114 tod_to_timeval(stck - TOD_UNIX_EPOCH, ts); 115 } 116 117 extern u64 sched_clock_base_cc; 118 119 /** 120 * get_clock_monotonic - returns current time in clock rate units 121 * 122 * The caller must ensure that preemption is disabled. 123 * The clock and sched_clock_base get changed via stop_machine. 124 * Therefore preemption must be disabled when calling this 125 * function, otherwise the returned value is not guaranteed to 126 * be monotonic. 127 */ 128 static inline unsigned long long get_clock_monotonic(void) 129 { 130 return get_clock_xt() - sched_clock_base_cc; 131 } 132 133 #endif 134