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 <linux/preempt.h>
14 #include <linux/time64.h>
15 #include <asm/lowcore.h>
16
17 /* The value of the TOD clock for 1.1.1970. */
18 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
19
20 extern u64 clock_comparator_max;
21
22 union tod_clock {
23 __uint128_t val;
24 struct {
25 __uint128_t ei : 8; /* epoch index */
26 __uint128_t tod : 64; /* bits 0-63 of tod clock */
27 __uint128_t : 40;
28 __uint128_t pf : 16; /* programmable field */
29 };
30 struct {
31 __uint128_t eitod : 72; /* epoch index + bits 0-63 tod clock */
32 __uint128_t : 56;
33 };
34 struct {
35 __uint128_t us : 60; /* micro-seconds */
36 __uint128_t sus : 12; /* sub-microseconds */
37 __uint128_t : 56;
38 };
39 } __packed;
40
41 /* Inline functions for clock register access. */
42 static inline int set_tod_clock(__u64 time)
43 {
44 int cc;
45
46 asm volatile(
47 " sck %1\n"
48 " ipm %0\n"
49 " srl %0,28\n"
50 : "=d" (cc) : "Q" (time) : "cc");
51 return cc;
52 }
53
54 static inline int store_tod_clock_ext_cc(union tod_clock *clk)
55 {
56 int cc;
57
58 asm volatile(
59 " stcke %1\n"
60 " ipm %0\n"
61 " srl %0,28\n"
62 : "=d" (cc), "=Q" (*clk) : : "cc");
63 return cc;
64 }
65
66 static __always_inline void store_tod_clock_ext(union tod_clock *tod)
67 {
68 asm volatile("stcke %0" : "=Q" (*tod) : : "cc");
69 }
70
71 static inline void set_clock_comparator(__u64 time)
72 {
73 asm volatile("sckc %0" : : "Q" (time));
74 }
75
76 static inline void set_tod_programmable_field(u16 val)
77 {
78 asm volatile(
79 " lgr 0,%[val]\n"
80 " sckpf\n"
81 :
82 : [val] "d" ((unsigned long)val)
83 : "");
84 }
85
86 void clock_comparator_work(void);
87
88 void __init time_early_init(void);
89
90 extern unsigned char ptff_function_mask[16];
91
92 /* Function codes for the ptff instruction. */
93 #define PTFF_QAF 0x00 /* query available functions */
94 #define PTFF_QTO 0x01 /* query tod offset */
95 #define PTFF_QSI 0x02 /* query steering information */
96 #define PTFF_QUI 0x04 /* query UTC information */
97 #define PTFF_ATO 0x40 /* adjust tod offset */
98 #define PTFF_STO 0x41 /* set tod offset */
99 #define PTFF_SFS 0x42 /* set fine steering rate */
100 #define PTFF_SGS 0x43 /* set gross steering rate */
101
102 /* Query TOD offset result */
103 struct ptff_qto {
104 unsigned long physical_clock;
105 unsigned long tod_offset;
106 unsigned long logical_tod_offset;
107 unsigned long tod_epoch_difference;
108 } __packed;
109
110 static inline int ptff_query(unsigned int nr)
111 {
112 unsigned char *ptr;
113
114 ptr = ptff_function_mask + (nr >> 3);
115 return (*ptr & (0x80 >> (nr & 7))) != 0;
116 }
117
118 /* Query UTC information result */
119 struct ptff_qui {
120 unsigned int tm : 2;
121 unsigned int ts : 2;
122 unsigned int : 28;
123 unsigned int pad_0x04;
124 unsigned long leap_event;
125 short old_leap;
126 short new_leap;
127 unsigned int pad_0x14;
128 unsigned long prt[5];
129 unsigned long cst[3];
130 unsigned int skew;
131 unsigned int pad_0x5c[41];
132 } __packed;
133
134 /*
135 * ptff - Perform timing facility function
136 * @ptff_block: Pointer to ptff parameter block
137 * @len: Length of parameter block
138 * @func: Function code
139 * Returns: Condition code (0 on success)
140 */
141 #define ptff(ptff_block, len, func) \
142 ({ \
143 struct addrtype { char _[len]; }; \
144 unsigned int reg0 = func; \
145 unsigned long reg1 = (unsigned long)(ptff_block); \
146 int rc; \
147 \
148 asm volatile( \
149 " lgr 0,%[reg0]\n" \
150 " lgr 1,%[reg1]\n" \
151 " ptff\n" \
152 " ipm %[rc]\n" \
153 " srl %[rc],28\n" \
154 : [rc] "=&d" (rc), "+m" (*(struct addrtype *)reg1) \
155 : [reg0] "d" (reg0), [reg1] "d" (reg1) \
156 : "cc", "", "1"); \
157 rc; \
158 })
159
160 static inline unsigned long local_tick_disable(void)
161 {
162 unsigned long old;
163
164 old = get_lowcore()->clock_comparator;
165 get_lowcore()->clock_comparator = clock_comparator_max;
166 set_clock_comparator(get_lowcore()->clock_comparator);
167 return old;
168 }
169
170 static inline void local_tick_enable(unsigned long comp)
171 {
172 get_lowcore()->clock_comparator = comp;
173 set_clock_comparator(get_lowcore()->clock_comparator);
174 }
175
176 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
177
178 typedef unsigned long cycles_t;
179
180 static __always_inline unsigned long get_tod_clock(void)
181 {
182 union tod_clock clk;
183
184 store_tod_clock_ext(&clk);
185 return clk.tod;
186 }
187
188 static inline unsigned long get_tod_clock_fast(void)
189 {
190 unsigned long clk;
191
192 asm volatile("stckf %0" : "=Q" (clk) : : "cc");
193 return clk;
194 }
195
196 static inline cycles_t get_cycles(void)
197 {
198 return (cycles_t) get_tod_clock() >> 2;
199 }
200 #define get_cycles get_cycles
201
202 int get_phys_clock(unsigned long *clock);
203 void init_cpu_timer(void);
204
205 extern union tod_clock tod_clock_base;
206
207 static __always_inline unsigned long __get_tod_clock_monotonic(void)
208 {
209 return get_tod_clock() - tod_clock_base.tod;
210 }
211
212 /**
213 * get_clock_monotonic - returns current time in clock rate units
214 *
215 * The clock and tod_clock_base get changed via stop_machine.
216 * Therefore preemption must be disabled, otherwise the returned
217 * value is not guaranteed to be monotonic.
218 */
219 static inline unsigned long get_tod_clock_monotonic(void)
220 {
221 unsigned long tod;
222
223 preempt_disable_notrace();
224 tod = __get_tod_clock_monotonic();
225 preempt_enable_notrace();
226 return tod;
227 }
228
229 /**
230 * tod_to_ns - convert a TOD format value to nanoseconds
231 * @todval: to be converted TOD format value
232 * Returns: number of nanoseconds that correspond to the TOD format value
233 *
234 * Converting a 64 Bit TOD format value to nanoseconds means that the value
235 * must be divided by 4.096. In order to achieve that we multiply with 125
236 * and divide by 512:
237 *
238 * ns = (todval * 125) >> 9;
239 *
240 * In order to avoid an overflow with the multiplication we can rewrite this.
241 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits)
242 * we end up with
243 *
244 * ns = ((2^9 * th + tl) * 125 ) >> 9;
245 * -> ns = (th * 125) + ((tl * 125) >> 9);
246 *
247 */
248 static __always_inline unsigned long tod_to_ns(unsigned long todval)
249 {
250 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
251 }
252
253 /**
254 * tod_after - compare two 64 bit TOD values
255 * @a: first 64 bit TOD timestamp
256 * @b: second 64 bit TOD timestamp
257 *
258 * Returns: true if a is later than b
259 */
260 static inline int tod_after(unsigned long a, unsigned long b)
261 {
262 if (MACHINE_HAS_SCC)
263 return (long) a > (long) b;
264 return a > b;
265 }
266
267 /**
268 * tod_after_eq - compare two 64 bit TOD values
269 * @a: first 64 bit TOD timestamp
270 * @b: second 64 bit TOD timestamp
271 *
272 * Returns: true if a is later than b
273 */
274 static inline int tod_after_eq(unsigned long a, unsigned long b)
275 {
276 if (MACHINE_HAS_SCC)
277 return (long) a >= (long) b;
278 return a >= b;
279 }
280
281 #endif
282
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