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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/errno.h>
11#include <asm/unistd.h>
12#include <asm/vdso/cp15.h>
13#include <uapi/linux/time.h>
14
15#define VDSO_HAS_CLOCK_GETRES 1
16
17extern struct vdso_data *__get_datapage(void);
18
19static __always_inline int gettimeofday_fallback(
20 struct __kernel_old_timeval *_tv,
21 struct timezone *_tz)
22{
23 register struct timezone *tz asm("r1") = _tz;
24 register struct __kernel_old_timeval *tv asm("r0") = _tv;
25 register long ret asm ("r0");
26 register long nr asm("r7") = __NR_gettimeofday;
27
28 asm volatile(
29 " swi #0\n"
30 : "=r" (ret)
31 : "r" (tv), "r" (tz), "r" (nr)
32 : "memory");
33
34 return ret;
35}
36
37static __always_inline long clock_gettime_fallback(
38 clockid_t _clkid,
39 struct __kernel_timespec *_ts)
40{
41 register struct __kernel_timespec *ts asm("r1") = _ts;
42 register clockid_t clkid asm("r0") = _clkid;
43 register long ret asm ("r0");
44 register long nr asm("r7") = __NR_clock_gettime64;
45
46 asm volatile(
47 " swi #0\n"
48 : "=r" (ret)
49 : "r" (clkid), "r" (ts), "r" (nr)
50 : "memory");
51
52 return ret;
53}
54
55static __always_inline long clock_gettime32_fallback(
56 clockid_t _clkid,
57 struct old_timespec32 *_ts)
58{
59 register struct old_timespec32 *ts asm("r1") = _ts;
60 register clockid_t clkid asm("r0") = _clkid;
61 register long ret asm ("r0");
62 register long nr asm("r7") = __NR_clock_gettime;
63
64 asm volatile(
65 " swi #0\n"
66 : "=r" (ret)
67 : "r" (clkid), "r" (ts), "r" (nr)
68 : "memory");
69
70 return ret;
71}
72
73static __always_inline int clock_getres_fallback(
74 clockid_t _clkid,
75 struct __kernel_timespec *_ts)
76{
77 register struct __kernel_timespec *ts asm("r1") = _ts;
78 register clockid_t clkid asm("r0") = _clkid;
79 register long ret asm ("r0");
80 register long nr asm("r7") = __NR_clock_getres_time64;
81
82 asm volatile(
83 " swi #0\n"
84 : "=r" (ret)
85 : "r" (clkid), "r" (ts), "r" (nr)
86 : "memory");
87
88 return ret;
89}
90
91static __always_inline int clock_getres32_fallback(
92 clockid_t _clkid,
93 struct old_timespec32 *_ts)
94{
95 register struct old_timespec32 *ts asm("r1") = _ts;
96 register clockid_t clkid asm("r0") = _clkid;
97 register long ret asm ("r0");
98 register long nr asm("r7") = __NR_clock_getres;
99
100 asm volatile(
101 " swi #0\n"
102 : "=r" (ret)
103 : "r" (clkid), "r" (ts), "r" (nr)
104 : "memory");
105
106 return ret;
107}
108
109static inline bool arm_vdso_hres_capable(void)
110{
111 return IS_ENABLED(CONFIG_ARM_ARCH_TIMER);
112}
113#define __arch_vdso_hres_capable arm_vdso_hres_capable
114
115static __always_inline u64 __arch_get_hw_counter(int clock_mode)
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
138static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
139{
140 return __get_datapage();
141}
142
143#endif /* !__ASSEMBLY__ */
144
145#endif /* __ASM_VDSO_GETTIMEOFDAY_H */