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