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 #include <asm/machine.h>
17 #include <asm/asm.h>
18
19 /* The value of the TOD clock for 1.1.1970. */
20 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
21
22 extern u64 clock_comparator_max;
23
24 union tod_clock {
25 __uint128_t val;
26 struct {
27 __uint128_t ei : 8; /* epoch index */
28 __uint128_t tod : 64; /* bits 0-63 of tod clock */
29 __uint128_t : 40;
30 __uint128_t pf : 16; /* programmable field */
31 };
32 struct {
33 __uint128_t eitod : 72; /* epoch index + bits 0-63 tod clock */
34 __uint128_t : 56;
35 };
36 struct {
37 __uint128_t us : 60; /* micro-seconds */
38 __uint128_t sus : 12; /* sub-microseconds */
39 __uint128_t : 56;
40 };
41 } __packed;
42
43 /* Inline functions for clock register access. */
set_tod_clock(__u64 time)44 static inline int set_tod_clock(__u64 time)
45 {
46 int cc;
47
48 asm volatile(
49 " sck %[time]\n"
50 CC_IPM(cc)
51 : CC_OUT(cc, cc)
52 : [time] "Q" (time)
53 : CC_CLOBBER);
54 return CC_TRANSFORM(cc);
55 }
56
store_tod_clock_ext_cc(union tod_clock * clk)57 static inline int store_tod_clock_ext_cc(union tod_clock *clk)
58 {
59 int cc;
60
61 asm volatile(
62 " stcke %[clk]\n"
63 CC_IPM(cc)
64 : CC_OUT(cc, cc), [clk] "=Q" (*clk)
65 :
66 : CC_CLOBBER);
67 return CC_TRANSFORM(cc);
68 }
69
store_tod_clock_ext(union tod_clock * tod)70 static __always_inline void store_tod_clock_ext(union tod_clock *tod)
71 {
72 asm volatile("stcke %0" : "=Q" (*tod) : : "cc");
73 }
74
set_clock_comparator(__u64 time)75 static inline void set_clock_comparator(__u64 time)
76 {
77 asm volatile("sckc %0" : : "Q" (time));
78 }
79
set_tod_programmable_field(u16 val)80 static inline void set_tod_programmable_field(u16 val)
81 {
82 asm volatile(
83 " lgr 0,%[val]\n"
84 " sckpf\n"
85 :
86 : [val] "d" ((unsigned long)val)
87 : "0");
88 }
89
90 void clock_comparator_work(void);
91
92 void __init time_early_init(void);
93
94 extern unsigned char ptff_function_mask[16];
95
96 /* Function codes for the ptff instruction. */
97 #define PTFF_QAF 0x00 /* query available functions */
98 #define PTFF_QTO 0x01 /* query tod offset */
99 #define PTFF_QSI 0x02 /* query steering information */
100 #define PTFF_QPT 0x03 /* query physical clock */
101 #define PTFF_QUI 0x04 /* query UTC information */
102 #define PTFF_ATO 0x40 /* adjust tod offset */
103 #define PTFF_STO 0x41 /* set tod offset */
104 #define PTFF_SFS 0x42 /* set fine steering rate */
105 #define PTFF_SGS 0x43 /* set gross steering rate */
106
107 /* Query TOD offset result */
108 struct ptff_qto {
109 unsigned long physical_clock;
110 unsigned long tod_offset;
111 unsigned long logical_tod_offset;
112 unsigned long tod_epoch_difference;
113 } __packed;
114
ptff_query(unsigned int nr)115 static inline int ptff_query(unsigned int nr)
116 {
117 unsigned char *ptr;
118
119 ptr = ptff_function_mask + (nr >> 3);
120 return (*ptr & (0x80 >> (nr & 7))) != 0;
121 }
122
123 /* Query UTC information result */
124 struct ptff_qui {
125 unsigned int tm : 2;
126 unsigned int ts : 2;
127 unsigned int : 28;
128 unsigned int pad_0x04;
129 unsigned long leap_event;
130 short old_leap;
131 short new_leap;
132 unsigned int pad_0x14;
133 unsigned long prt[5];
134 unsigned long cst[3];
135 unsigned int skew;
136 unsigned int pad_0x5c[41];
137 } __packed;
138
139 /*
140 * ptff - Perform timing facility function
141 * @ptff_block: Pointer to ptff parameter block
142 * @len: Length of parameter block
143 * @func: Function code
144 * Returns: Condition code (0 on success)
145 */
146 #define ptff(ptff_block, len, func) \
147 ({ \
148 struct addrtype { char _[len]; }; \
149 unsigned int reg0 = func; \
150 unsigned long reg1 = (unsigned long)(ptff_block); \
151 int rc; \
152 \
153 asm volatile( \
154 " lgr 0,%[reg0]\n" \
155 " lgr 1,%[reg1]\n" \
156 " ptff\n" \
157 CC_IPM(rc) \
158 : CC_OUT(rc, rc), "+m" (*(struct addrtype *)reg1) \
159 : [reg0] "d" (reg0), [reg1] "d" (reg1) \
160 : CC_CLOBBER_LIST("0", "1")); \
161 CC_TRANSFORM(rc); \
162 })
163
local_tick_disable(void)164 static inline unsigned long local_tick_disable(void)
165 {
166 unsigned long old;
167
168 old = get_lowcore()->clock_comparator;
169 get_lowcore()->clock_comparator = clock_comparator_max;
170 set_clock_comparator(get_lowcore()->clock_comparator);
171 return old;
172 }
173
local_tick_enable(unsigned long comp)174 static inline void local_tick_enable(unsigned long comp)
175 {
176 get_lowcore()->clock_comparator = comp;
177 set_clock_comparator(get_lowcore()->clock_comparator);
178 }
179
180 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
181
182 typedef unsigned long cycles_t;
183
get_tod_clock(void)184 static __always_inline unsigned long get_tod_clock(void)
185 {
186 union tod_clock clk;
187
188 store_tod_clock_ext(&clk);
189 return clk.tod;
190 }
191
get_tod_clock_fast(void)192 static inline unsigned long get_tod_clock_fast(void)
193 {
194 unsigned long clk;
195
196 asm volatile("stckf %0" : "=Q" (clk) : : "cc");
197 return clk;
198 }
199
get_cycles(void)200 static inline cycles_t get_cycles(void)
201 {
202 return (cycles_t) get_tod_clock() >> 2;
203 }
204 #define get_cycles get_cycles
205
206 int get_phys_clock(unsigned long *clock);
207 void init_cpu_timer(void);
208
209 extern union tod_clock tod_clock_base;
210
__get_tod_clock_monotonic(void)211 static __always_inline unsigned long __get_tod_clock_monotonic(void)
212 {
213 return get_tod_clock() - tod_clock_base.tod;
214 }
215
216 /**
217 * get_clock_monotonic - returns current time in clock rate units
218 *
219 * The clock and tod_clock_base get changed via stop_machine.
220 * Therefore preemption must be disabled, otherwise the returned
221 * value is not guaranteed to be monotonic.
222 */
get_tod_clock_monotonic(void)223 static inline unsigned long get_tod_clock_monotonic(void)
224 {
225 unsigned long tod;
226
227 preempt_disable_notrace();
228 tod = __get_tod_clock_monotonic();
229 preempt_enable_notrace();
230 return tod;
231 }
232
233 /**
234 * tod_to_ns - convert a TOD format value to nanoseconds
235 * @todval: to be converted TOD format value
236 * Returns: number of nanoseconds that correspond to the TOD format value
237 *
238 * Converting a 64 Bit TOD format value to nanoseconds means that the value
239 * must be divided by 4.096. In order to achieve that we multiply with 125
240 * and divide by 512:
241 *
242 * ns = (todval * 125) >> 9;
243 *
244 * In order to avoid an overflow with the multiplication we can rewrite this.
245 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits)
246 * we end up with
247 *
248 * ns = ((2^9 * th + tl) * 125 ) >> 9;
249 * -> ns = (th * 125) + ((tl * 125) >> 9);
250 *
251 */
tod_to_ns(unsigned long todval)252 static __always_inline unsigned long tod_to_ns(unsigned long todval)
253 {
254 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
255 }
256
eitod_to_ns(u128 todval)257 static __always_inline u128 eitod_to_ns(u128 todval)
258 {
259 return (todval * 125) >> 9;
260 }
261
262 /**
263 * tod_after - compare two 64 bit TOD values
264 * @a: first 64 bit TOD timestamp
265 * @b: second 64 bit TOD timestamp
266 *
267 * Returns: true if a is later than b
268 */
tod_after(unsigned long a,unsigned long b)269 static inline int tod_after(unsigned long a, unsigned long b)
270 {
271 if (machine_has_scc())
272 return (long) a > (long) b;
273 return a > b;
274 }
275
276 /**
277 * tod_after_eq - compare two 64 bit TOD values
278 * @a: first 64 bit TOD timestamp
279 * @b: second 64 bit TOD timestamp
280 *
281 * Returns: true if a is later than b
282 */
tod_after_eq(unsigned long a,unsigned long b)283 static inline int tod_after_eq(unsigned long a, unsigned long b)
284 {
285 if (machine_has_scc())
286 return (long) a >= (long) b;
287 return a >= b;
288 }
289
290 #endif
291