3 * Copyright IBM Corp. 1999
5 * Derived from "include/asm-i386/timex.h"
6 * Copyright (C) 1992, Linus Torvalds
9 #ifndef _ASM_S390_TIMEX_H
10 #define _ASM_S390_TIMEX_H
12 #include <asm/lowcore.h>
13 #include <linux/time64.h>
15 /* The value of the TOD clock for 1.1.1970. */
16 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
18 /* Inline functions for clock register access. */
19 static inline int set_tod_clock(__u64 time)
27 : "=d" (cc) : "Q" (time) : "cc");
31 static inline int store_tod_clock(__u64 *time)
39 : "=d" (cc), "=Q" (*time) : : "cc");
43 static inline void set_clock_comparator(__u64 time)
45 asm volatile("sckc %0" : : "Q" (time));
48 static inline void store_clock_comparator(__u64 *time)
50 asm volatile("stckc %0" : "=Q" (*time));
53 void clock_comparator_work(void);
55 void __init time_early_init(void);
57 extern unsigned char ptff_function_mask[16];
59 /* Function codes for the ptff instruction. */
60 #define PTFF_QAF 0x00 /* query available functions */
61 #define PTFF_QTO 0x01 /* query tod offset */
62 #define PTFF_QSI 0x02 /* query steering information */
63 #define PTFF_QUI 0x04 /* query UTC information */
64 #define PTFF_ATO 0x40 /* adjust tod offset */
65 #define PTFF_STO 0x41 /* set tod offset */
66 #define PTFF_SFS 0x42 /* set fine steering rate */
67 #define PTFF_SGS 0x43 /* set gross steering rate */
69 /* Query TOD offset result */
71 unsigned long long physical_clock;
72 unsigned long long tod_offset;
73 unsigned long long logical_tod_offset;
74 unsigned long long tod_epoch_difference;
77 static inline int ptff_query(unsigned int nr)
81 ptr = ptff_function_mask + (nr >> 3);
82 return (*ptr & (0x80 >> (nr & 7))) != 0;
85 /* Query UTC information result */
90 unsigned int pad_0x04;
91 unsigned long leap_event;
94 unsigned int pad_0x14;
98 unsigned int pad_0x5c[41];
102 * ptff - Perform timing facility function
103 * @ptff_block: Pointer to ptff parameter block
104 * @len: Length of parameter block
105 * @func: Function code
106 * Returns: Condition code (0 on success)
108 #define ptff(ptff_block, len, func) \
110 struct addrtype { char _[len]; }; \
111 register unsigned int reg0 asm("0") = func; \
112 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\
119 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \
120 : "d" (reg0), "d" (reg1) : "cc"); \
124 static inline unsigned long long local_tick_disable(void)
126 unsigned long long old;
128 old = S390_lowcore.clock_comparator;
129 S390_lowcore.clock_comparator = -1ULL;
130 set_clock_comparator(S390_lowcore.clock_comparator);
134 static inline void local_tick_enable(unsigned long long comp)
136 S390_lowcore.clock_comparator = comp;
137 set_clock_comparator(S390_lowcore.clock_comparator);
140 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
141 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
143 typedef unsigned long long cycles_t;
145 static inline void get_tod_clock_ext(char *clk)
147 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
149 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
152 static inline unsigned long long get_tod_clock(void)
154 unsigned char clk[STORE_CLOCK_EXT_SIZE];
156 get_tod_clock_ext(clk);
157 return *((unsigned long long *)&clk[1]);
160 static inline unsigned long long get_tod_clock_fast(void)
162 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
163 unsigned long long clk;
165 asm volatile("stckf %0" : "=Q" (clk) : : "cc");
168 return get_tod_clock();
172 static inline cycles_t get_cycles(void)
174 return (cycles_t) get_tod_clock() >> 2;
177 int get_phys_clock(unsigned long long *clock);
178 void init_cpu_timer(void);
179 unsigned long long monotonic_clock(void);
181 extern u64 sched_clock_base_cc;
184 * get_clock_monotonic - returns current time in clock rate units
186 * The caller must ensure that preemption is disabled.
187 * The clock and sched_clock_base get changed via stop_machine.
188 * Therefore preemption must be disabled when calling this
189 * function, otherwise the returned value is not guaranteed to
192 static inline unsigned long long get_tod_clock_monotonic(void)
194 return get_tod_clock() - sched_clock_base_cc;
198 * tod_to_ns - convert a TOD format value to nanoseconds
199 * @todval: to be converted TOD format value
200 * Returns: number of nanoseconds that correspond to the TOD format value
202 * Converting a 64 Bit TOD format value to nanoseconds means that the value
203 * must be divided by 4.096. In order to achieve that we multiply with 125
206 * ns = (todval * 125) >> 9;
208 * In order to avoid an overflow with the multiplication we can rewrite this.
209 * With a split todval == 2^32 * th + tl (th upper 32 bits, tl lower 32 bits)
212 * ns = ((2^32 * th + tl) * 125 ) >> 9;
213 * -> ns = (2^23 * th * 125) + ((tl * 125) >> 9);
216 static inline unsigned long long tod_to_ns(unsigned long long todval)
218 unsigned long long ns;
220 ns = ((todval >> 32) << 23) * 125;
221 ns += ((todval & 0xffffffff) * 125) >> 9;