1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * S390 version
4 * Copyright IBM Corp. 1999
5 *
6 * Derived from "include/asm-i386/timex.h"
7 * Copyright (C) 1992, Linus Torvalds
8 */
9
10 #ifndef _ASM_S390_TIMEX_H
11 #define _ASM_S390_TIMEX_H
12
13 #include <asm/lowcore.h>
14 #include <linux/time64.h>
15
16 /* The value of the TOD clock for 1.1.1970. */
17 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
18
19 extern u64 clock_comparator_max;
20
21 /* Inline functions for clock register access. */
set_tod_clock(__u64 time)22 static inline int set_tod_clock(__u64 time)
23 {
24 int cc;
25
26 asm volatile(
27 " sck %1\n"
28 " ipm %0\n"
29 " srl %0,28\n"
30 : "=d" (cc) : "Q" (time) : "cc");
31 return cc;
32 }
33
store_tod_clock(__u64 * time)34 static inline int store_tod_clock(__u64 *time)
35 {
36 int cc;
37
38 asm volatile(
39 " stck %1\n"
40 " ipm %0\n"
41 " srl %0,28\n"
42 : "=d" (cc), "=Q" (*time) : : "cc");
43 return cc;
44 }
45
set_clock_comparator(__u64 time)46 static inline void set_clock_comparator(__u64 time)
47 {
48 asm volatile("sckc %0" : : "Q" (time));
49 }
50
store_clock_comparator(__u64 * time)51 static inline void store_clock_comparator(__u64 *time)
52 {
53 asm volatile("stckc %0" : "=Q" (*time));
54 }
55
56 void clock_comparator_work(void);
57
58 void __init time_early_init(void);
59
60 extern unsigned char ptff_function_mask[16];
61
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 */
71
72 /* Query TOD offset result */
73 struct ptff_qto {
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;
78 } __packed;
79
ptff_query(unsigned int nr)80 static inline int ptff_query(unsigned int nr)
81 {
82 unsigned char *ptr;
83
84 ptr = ptff_function_mask + (nr >> 3);
85 return (*ptr & (0x80 >> (nr & 7))) != 0;
86 }
87
88 /* Query UTC information result */
89 struct ptff_qui {
90 unsigned int tm : 2;
91 unsigned int ts : 2;
92 unsigned int : 28;
93 unsigned int pad_0x04;
94 unsigned long leap_event;
95 short old_leap;
96 short new_leap;
97 unsigned int pad_0x14;
98 unsigned long prt[5];
99 unsigned long cst[3];
100 unsigned int skew;
101 unsigned int pad_0x5c[41];
102 } __packed;
103
104 /*
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)
110 */
111 #define ptff(ptff_block, len, func) \
112 ({ \
113 struct addrtype { char _[len]; }; \
114 register unsigned int reg0 asm("0") = func; \
115 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\
116 int rc; \
117 \
118 asm volatile( \
119 " .word 0x0104\n" \
120 " ipm %0\n" \
121 " srl %0,28\n" \
122 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \
123 : "d" (reg0), "d" (reg1) : "cc"); \
124 rc; \
125 })
126
local_tick_disable(void)127 static inline unsigned long long local_tick_disable(void)
128 {
129 unsigned long long old;
130
131 old = S390_lowcore.clock_comparator;
132 S390_lowcore.clock_comparator = clock_comparator_max;
133 set_clock_comparator(S390_lowcore.clock_comparator);
134 return old;
135 }
136
local_tick_enable(unsigned long long comp)137 static inline void local_tick_enable(unsigned long long comp)
138 {
139 S390_lowcore.clock_comparator = comp;
140 set_clock_comparator(S390_lowcore.clock_comparator);
141 }
142
143 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
144 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
145
146 typedef unsigned long long cycles_t;
147
get_tod_clock_ext(char * clk)148 static inline void get_tod_clock_ext(char *clk)
149 {
150 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
151
152 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
153 }
154
get_tod_clock(void)155 static inline unsigned long long get_tod_clock(void)
156 {
157 unsigned char clk[STORE_CLOCK_EXT_SIZE];
158
159 get_tod_clock_ext(clk);
160 return *((unsigned long long *)&clk[1]);
161 }
162
get_tod_clock_fast(void)163 static inline unsigned long long get_tod_clock_fast(void)
164 {
165 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
166 unsigned long long clk;
167
168 asm volatile("stckf %0" : "=Q" (clk) : : "cc");
169 return clk;
170 #else
171 return get_tod_clock();
172 #endif
173 }
174
get_cycles(void)175 static inline cycles_t get_cycles(void)
176 {
177 return (cycles_t) get_tod_clock() >> 2;
178 }
179
180 int get_phys_clock(unsigned long *clock);
181 void init_cpu_timer(void);
182 unsigned long long monotonic_clock(void);
183
184 extern unsigned char tod_clock_base[16] __aligned(8);
185
186 /**
187 * get_clock_monotonic - returns current time in clock rate units
188 *
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
193 * be monotonic.
194 */
get_tod_clock_monotonic(void)195 static inline unsigned long long get_tod_clock_monotonic(void)
196 {
197 return get_tod_clock() - *(unsigned long long *) &tod_clock_base[1];
198 }
199
200 /**
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
204 *
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
207 * and divide by 512:
208 *
209 * ns = (todval * 125) >> 9;
210 *
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)
213 * we end up with
214 *
215 * ns = ((2^9 * th + tl) * 125 ) >> 9;
216 * -> ns = (th * 125) + ((tl * 125) >> 9);
217 *
218 */
tod_to_ns(unsigned long long todval)219 static inline unsigned long long tod_to_ns(unsigned long long todval)
220 {
221 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
222 }
223
224 /**
225 * tod_after - compare two 64 bit TOD values
226 * @a: first 64 bit TOD timestamp
227 * @b: second 64 bit TOD timestamp
228 *
229 * Returns: true if a is later than b
230 */
tod_after(unsigned long long a,unsigned long long b)231 static inline int tod_after(unsigned long long a, unsigned long long b)
232 {
233 if (MACHINE_HAS_SCC)
234 return (long long) a > (long long) b;
235 return a > b;
236 }
237
238 /**
239 * tod_after_eq - compare two 64 bit TOD values
240 * @a: first 64 bit TOD timestamp
241 * @b: second 64 bit TOD timestamp
242 *
243 * Returns: true if a is later than b
244 */
tod_after_eq(unsigned long long a,unsigned long long b)245 static inline int tod_after_eq(unsigned long long a, unsigned long long b)
246 {
247 if (MACHINE_HAS_SCC)
248 return (long long) a >= (long long) b;
249 return a >= b;
250 }
251
252 #endif
253
