aboutsummaryrefslogtreecommitdiff
path: root/arch/s390/include/asm/timex.h
blob: 93f2eb3f277c6550d54982403a8a04419ea8543f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
/*
 *  S390 version
 *    Copyright IBM Corp. 1999
 *
 *  Derived from "include/asm-i386/timex.h"
 *    Copyright (C) 1992, Linus Torvalds
 */

#ifndef _ASM_S390_TIMEX_H
#define _ASM_S390_TIMEX_H

#include <asm/lowcore.h>
#include <linux/time64.h>

/* The value of the TOD clock for 1.1.1970. */
#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL

extern u64 clock_comparator_max;

/* Inline functions for clock register access. */
static inline int set_tod_clock(__u64 time)
{
	int cc;

	asm volatile(
		"   sck   %1\n"
		"   ipm   %0\n"
		"   srl   %0,28\n"
		: "=d" (cc) : "Q" (time) : "cc");
	return cc;
}

static inline int store_tod_clock(__u64 *time)
{
	int cc;

	asm volatile(
		"   stck  %1\n"
		"   ipm   %0\n"
		"   srl   %0,28\n"
		: "=d" (cc), "=Q" (*time) : : "cc");
	return cc;
}

static inline void set_clock_comparator(__u64 time)
{
	asm volatile("sckc %0" : : "Q" (time));
}

static inline void store_clock_comparator(__u64 *time)
{
	asm volatile("stckc %0" : "=Q" (*time));
}

void clock_comparator_work(void);

void __init time_early_init(void);

extern unsigned char ptff_function_mask[16];

/* Function codes for the ptff instruction. */
#define PTFF_QAF	0x00	/* query available functions */
#define PTFF_QTO	0x01	/* query tod offset */
#define PTFF_QSI	0x02	/* query steering information */
#define PTFF_QUI	0x04	/* query UTC information */
#define PTFF_ATO	0x40	/* adjust tod offset */
#define PTFF_STO	0x41	/* set tod offset */
#define PTFF_SFS	0x42	/* set fine steering rate */
#define PTFF_SGS	0x43	/* set gross steering rate */

/* Query TOD offset result */
struct ptff_qto {
	unsigned long long physical_clock;
	unsigned long long tod_offset;
	unsigned long long logical_tod_offset;
	unsigned long long tod_epoch_difference;
} __packed;

static inline int ptff_query(unsigned int nr)
{
	unsigned char *ptr;

	ptr = ptff_function_mask + (nr >> 3);
	return (*ptr & (0x80 >> (nr & 7))) != 0;
}

/* Query UTC information result */
struct ptff_qui {
	unsigned int tm : 2;
	unsigned int ts : 2;
	unsigned int : 28;
	unsigned int pad_0x04;
	unsigned long leap_event;
	short old_leap;
	short new_leap;
	unsigned int pad_0x14;
	unsigned long prt[5];
	unsigned long cst[3];
	unsigned int skew;
	unsigned int pad_0x5c[41];
} __packed;

/*
 * ptff - Perform timing facility function
 * @ptff_block: Pointer to ptff parameter block
 * @len: Length of parameter block
 * @func: Function code
 * Returns: Condition code (0 on success)
 */
#define ptff(ptff_block, len, func)					\
({									\
	struct addrtype { char _[len]; };				\
	register unsigned int reg0 asm("0") = func;			\
	register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\
	int rc;								\
									\
	asm volatile(							\
		"	.word	0x0104\n"				\
		"	ipm	%0\n"					\
		"	srl	%0,28\n"				\
		: "=d" (rc), "+m" (*(struct addrtype *) reg1)		\
		: "d" (reg0), "d" (reg1) : "cc");			\
	rc;								\
})

static inline unsigned long long local_tick_disable(void)
{
	unsigned long long old;

	old = S390_lowcore.clock_comparator;
	S390_lowcore.clock_comparator = clock_comparator_max;
	set_clock_comparator(S390_lowcore.clock_comparator);
	return old;
}

static inline void local_tick_enable(unsigned long long comp)
{
	S390_lowcore.clock_comparator = comp;
	set_clock_comparator(S390_lowcore.clock_comparator);
}

#define CLOCK_TICK_RATE		1193180 /* Underlying HZ */
#define STORE_CLOCK_EXT_SIZE	16	/* stcke writes 16 bytes */

typedef unsigned long long cycles_t;

static inline void get_tod_clock_ext(char *clk)
{
	typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;

	asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
}

static inline unsigned long long get_tod_clock(void)
{
	unsigned char clk[STORE_CLOCK_EXT_SIZE];

	get_tod_clock_ext(clk);
	return *((unsigned long long *)&clk[1]);
}

static inline unsigned long long get_tod_clock_fast(void)
{
#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
	unsigned long long clk;

	asm volatile("stckf %0" : "=Q" (clk) : : "cc");
	return clk;
#else
	return get_tod_clock();
#endif
}

static inline cycles_t get_cycles(void)
{
	return (cycles_t) get_tod_clock() >> 2;
}

int get_phys_clock(unsigned long *clock);
void init_cpu_timer(void);
unsigned long long monotonic_clock(void);

extern unsigned char tod_clock_base[16] __aligned(8);

/**
 * get_clock_monotonic - returns current time in clock rate units
 *
 * The caller must ensure that preemption is disabled.
 * The clock and tod_clock_base get changed via stop_machine.
 * Therefore preemption must be disabled when calling this
 * function, otherwise the returned value is not guaranteed to
 * be monotonic.
 */
static inline unsigned long long get_tod_clock_monotonic(void)
{
	return get_tod_clock() - *(unsigned long long *) &tod_clock_base[1];
}

/**
 * tod_to_ns - convert a TOD format value to nanoseconds
 * @todval: to be converted TOD format value
 * Returns: number of nanoseconds that correspond to the TOD format value
 *
 * Converting a 64 Bit TOD format value to nanoseconds means that the value
 * must be divided by 4.096. In order to achieve that we multiply with 125
 * and divide by 512:
 *
 *    ns = (todval * 125) >> 9;
 *
 * In order to avoid an overflow with the multiplication we can rewrite this.
 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits)
 * we end up with
 *
 *    ns = ((2^9 * th + tl) * 125 ) >> 9;
 * -> ns = (th * 125) + ((tl * 125) >> 9);
 *
 */
static inline unsigned long long tod_to_ns(unsigned long long todval)
{
	return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9);
}

/**
 * tod_after - compare two 64 bit TOD values
 * @a: first 64 bit TOD timestamp
 * @b: second 64 bit TOD timestamp
 *
 * Returns: true if a is later than b
 */
static inline int tod_after(unsigned long long a, unsigned long long b)
{
	if (MACHINE_HAS_SCC)
		return (long long) a > (long long) b;
	return a > b;
}

/**
 * tod_after_eq - compare two 64 bit TOD values
 * @a: first 64 bit TOD timestamp
 * @b: second 64 bit TOD timestamp
 *
 * Returns: true if a is later than b
 */
static inline int tod_after_eq(unsigned long long a, unsigned long long b)
{
	if (MACHINE_HAS_SCC)
		return (long long) a >= (long long) b;
	return a >= b;
}

#endif