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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2018 ARM Limited
4 */
5#ifndef __ASM_VDSO_GETTIMEOFDAY_H
6#define __ASM_VDSO_GETTIMEOFDAY_H
7
8#ifndef __ASSEMBLY__
9
10#include <asm/barrier.h>
11#include <asm/errno.h>
12#include <asm/unistd.h>
13#include <asm/vdso/cp15.h>
14#include <uapi/linux/time.h>
15
16#define VDSO_HAS_CLOCK_GETRES 1
17
18static __always_inline int gettimeofday_fallback(
19 struct __kernel_old_timeval *_tv,
20 struct timezone *_tz)
21{
22 register struct timezone *tz asm("r1") = _tz;
23 register struct __kernel_old_timeval *tv asm("r0") = _tv;
24 register long ret asm ("r0");
25 register long nr asm("r7") = __NR_gettimeofday;
26
27 asm volatile(
28 " swi #0\n"
29 : "=r" (ret)
30 : "r" (tv), "r" (tz), "r" (nr)
31 : "memory");
32
33 return ret;
34}
35
36static __always_inline long clock_gettime_fallback(
37 clockid_t _clkid,
38 struct __kernel_timespec *_ts)
39{
40 register struct __kernel_timespec *ts asm("r1") = _ts;
41 register clockid_t clkid asm("r0") = _clkid;
42 register long ret asm ("r0");
43 register long nr asm("r7") = __NR_clock_gettime64;
44
45 asm volatile(
46 " swi #0\n"
47 : "=r" (ret)
48 : "r" (clkid), "r" (ts), "r" (nr)
49 : "memory");
50
51 return ret;
52}
53
54static __always_inline long clock_gettime32_fallback(
55 clockid_t _clkid,
56 struct old_timespec32 *_ts)
57{
58 register struct old_timespec32 *ts asm("r1") = _ts;
59 register clockid_t clkid asm("r0") = _clkid;
60 register long ret asm ("r0");
61 register long nr asm("r7") = __NR_clock_gettime;
62
63 asm volatile(
64 " swi #0\n"
65 : "=r" (ret)
66 : "r" (clkid), "r" (ts), "r" (nr)
67 : "memory");
68
69 return ret;
70}
71
72static __always_inline int clock_getres_fallback(
73 clockid_t _clkid,
74 struct __kernel_timespec *_ts)
75{
76 register struct __kernel_timespec *ts asm("r1") = _ts;
77 register clockid_t clkid asm("r0") = _clkid;
78 register long ret asm ("r0");
79 register long nr asm("r7") = __NR_clock_getres_time64;
80
81 asm volatile(
82 " swi #0\n"
83 : "=r" (ret)
84 : "r" (clkid), "r" (ts), "r" (nr)
85 : "memory");
86
87 return ret;
88}
89
90static __always_inline int clock_getres32_fallback(
91 clockid_t _clkid,
92 struct old_timespec32 *_ts)
93{
94 register struct old_timespec32 *ts asm("r1") = _ts;
95 register clockid_t clkid asm("r0") = _clkid;
96 register long ret asm ("r0");
97 register long nr asm("r7") = __NR_clock_getres;
98
99 asm volatile(
100 " swi #0\n"
101 : "=r" (ret)
102 : "r" (clkid), "r" (ts), "r" (nr)
103 : "memory");
104
105 return ret;
106}
107
108static inline bool arm_vdso_hres_capable(void)
109{
110 return IS_ENABLED(CONFIG_ARM_ARCH_TIMER);
111}
112#define __arch_vdso_hres_capable arm_vdso_hres_capable
113
114static __always_inline u64 __arch_get_hw_counter(int clock_mode,
115 const struct vdso_time_data *vd)
116{
117#ifdef CONFIG_ARM_ARCH_TIMER
118 u64 cycle_now;
119
120 /*
121 * Core checks for mode already, so this raced against a concurrent
122 * update. Return something. Core will do another round and then
123 * see the mode change and fallback to the syscall.
124 */
125 if (clock_mode == VDSO_CLOCKMODE_NONE)
126 return 0;
127
128 isb();
129 cycle_now = read_sysreg(CNTVCT);
130
131 return cycle_now;
132#else
133 /* Make GCC happy. This is compiled out anyway */
134 return 0;
135#endif
136}
137
138#endif /* !__ASSEMBLY__ */
139
140#endif /* __ASM_VDSO_GETTIMEOFDAY_H */