1 /* SPDX-License-Identifier: GPL-2.0 */
4 * Copyright IBM Corp. 1999
6 * Derived from "include/asm-i386/timex.h"
7 * Copyright (C) 1992, Linus Torvalds
10 #ifndef _ASM_S390_TIMEX_H
11 #define _ASM_S390_TIMEX_H
13 #include <asm/lowcore.h>
14 #include <linux/time64.h>
16 /* The value of the TOD clock for 1.1.1970. */
17 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
19 extern u64 clock_comparator_max;
21 /* Inline functions for clock register access. */
22 static inline int set_tod_clock(__u64 time)
30 : "=d" (cc) : "Q" (time) : "cc");
34 static inline int store_tod_clock(__u64 *time)
42 : "=d" (cc), "=Q" (*time) : : "cc");
46 static inline void set_clock_comparator(__u64 time)
48 asm volatile("sckc %0" : : "Q" (time));
51 static inline void store_clock_comparator(__u64 *time)
53 asm volatile("stckc %0" : "=Q" (*time));
56 void clock_comparator_work(void);
58 void __init time_early_init(void);
60 extern unsigned char ptff_function_mask[16];
62 /* Function codes for the ptff instruction. */
63 #define PTFF_QAF 0x00 /* query available functions */
64 #define PTFF_QTO 0x01 /* query tod offset */
65 #define PTFF_QSI 0x02 /* query steering information */
66 #define PTFF_QUI 0x04 /* query UTC information */
67 #define PTFF_ATO 0x40 /* adjust tod offset */
68 #define PTFF_STO 0x41 /* set tod offset */
69 #define PTFF_SFS 0x42 /* set fine steering rate */
70 #define PTFF_SGS 0x43 /* set gross steering rate */
72 /* Query TOD offset result */
74 unsigned long long physical_clock;
75 unsigned long long tod_offset;
76 unsigned long long logical_tod_offset;
77 unsigned long long tod_epoch_difference;
80 static inline int ptff_query(unsigned int nr)
84 ptr = ptff_function_mask + (nr >> 3);
85 return (*ptr & (0x80 >> (nr & 7))) != 0;
88 /* Query UTC information result */
93 unsigned int pad_0x04;
94 unsigned long leap_event;
97 unsigned int pad_0x14;
101 unsigned int pad_0x5c[41];
105 * ptff - Perform timing facility function
106 * @ptff_block: Pointer to ptff parameter block
107 * @len: Length of parameter block
108 * @func: Function code
109 * Returns: Condition code (0 on success)
111 #define ptff(ptff_block, len, func) \
113 struct addrtype { char _[len]; }; \
114 register unsigned int reg0 asm("0") = func; \
115 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\
122 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \
123 : "d" (reg0), "d" (reg1) : "cc"); \
127 static inline unsigned long long local_tick_disable(void)
129 unsigned long long old;
131 old = S390_lowcore.clock_comparator;
132 S390_lowcore.clock_comparator = clock_comparator_max;
133 set_clock_comparator(S390_lowcore.clock_comparator);
137 static inline void local_tick_enable(unsigned long long comp)
139 S390_lowcore.clock_comparator = comp;
140 set_clock_comparator(S390_lowcore.clock_comparator);
143 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
144 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
146 typedef unsigned long long cycles_t;
148 static inline void get_tod_clock_ext(char *clk)
150 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
152 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
155 static inline unsigned long long get_tod_clock(void)
157 unsigned char clk[STORE_CLOCK_EXT_SIZE];
159 get_tod_clock_ext(clk);
160 return *((unsigned long long *)&clk[1]);
163 static inline unsigned long long get_tod_clock_fast(void)
165 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
166 unsigned long long clk;
168 asm volatile("stckf %0" : "=Q" (clk) : : "cc");
171 return get_tod_clock();
175 static inline cycles_t get_cycles(void)
177 return (cycles_t) get_tod_clock() >> 2;
180 int get_phys_clock(unsigned long *clock);
181 void init_cpu_timer(void);
182 unsigned long long monotonic_clock(void);
184 extern unsigned char tod_clock_base[16] __aligned(8);
187 * get_clock_monotonic - returns current time in clock rate units
189 * The caller must ensure that preemption is disabled.
190 * The clock and tod_clock_base get changed via stop_machine.
191 * Therefore preemption must be disabled when calling this
192 * function, otherwise the returned value is not guaranteed to
195 static inline unsigned long long get_tod_clock_monotonic(void)
197 return get_tod_clock() - *(unsigned long long *) &tod_clock_base[1];
201 * tod_to_ns - convert a TOD format value to nanoseconds
202 * @todval: to be converted TOD format value
203 * Returns: number of nanoseconds that correspond to the TOD format value
205 * Converting a 64 Bit TOD format value to nanoseconds means that the value
206 * must be divided by 4.096. In order to achieve that we multiply with 125
209 * ns = (todval * 125) >> 9;
211 * In order to avoid an overflow with the multiplication we can rewrite this.
212 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits)
215 * ns = ((2^9 * th + tl) * 125 ) >> 9;
216 * -> ns = (th * 125) + ((tl * 125) >> 9);
219 static inline unsigned long long tod_to_ns(unsigned long long todval)
221 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
225 * tod_after - compare two 64 bit TOD values
226 * @a: first 64 bit TOD timestamp
227 * @b: second 64 bit TOD timestamp
229 * Returns: true if a is later than b
231 static inline int tod_after(unsigned long long a, unsigned long long b)
234 return (long long) a > (long long) b;
239 * tod_after_eq - compare two 64 bit TOD values
240 * @a: first 64 bit TOD timestamp
241 * @b: second 64 bit TOD timestamp
243 * Returns: true if a is later than b
245 static inline int tod_after_eq(unsigned long long a, unsigned long long b)
248 return (long long) a >= (long long) b;