xref: /OK3568_Linux_fs/kernel/arch/arm64/include/asm/vdso/gettimeofday.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2018 ARM Limited
4*4882a593Smuzhiyun  */
5*4882a593Smuzhiyun #ifndef __ASM_VDSO_GETTIMEOFDAY_H
6*4882a593Smuzhiyun #define __ASM_VDSO_GETTIMEOFDAY_H
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #ifndef __ASSEMBLY__
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <asm/barrier.h>
11*4882a593Smuzhiyun #include <asm/unistd.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define VDSO_HAS_CLOCK_GETRES		1
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun static __always_inline
gettimeofday_fallback(struct __kernel_old_timeval * _tv,struct timezone * _tz)16*4882a593Smuzhiyun int gettimeofday_fallback(struct __kernel_old_timeval *_tv,
17*4882a593Smuzhiyun 			  struct timezone *_tz)
18*4882a593Smuzhiyun {
19*4882a593Smuzhiyun 	register struct timezone *tz asm("x1") = _tz;
20*4882a593Smuzhiyun 	register struct __kernel_old_timeval *tv asm("x0") = _tv;
21*4882a593Smuzhiyun 	register long ret asm ("x0");
22*4882a593Smuzhiyun 	register long nr asm("x8") = __NR_gettimeofday;
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	asm volatile(
25*4882a593Smuzhiyun 	"       svc #0\n"
26*4882a593Smuzhiyun 	: "=r" (ret)
27*4882a593Smuzhiyun 	: "r" (tv), "r" (tz), "r" (nr)
28*4882a593Smuzhiyun 	: "memory");
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	return ret;
31*4882a593Smuzhiyun }
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun static __always_inline
clock_gettime_fallback(clockid_t _clkid,struct __kernel_timespec * _ts)34*4882a593Smuzhiyun long clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
35*4882a593Smuzhiyun {
36*4882a593Smuzhiyun 	register struct __kernel_timespec *ts asm("x1") = _ts;
37*4882a593Smuzhiyun 	register clockid_t clkid asm("x0") = _clkid;
38*4882a593Smuzhiyun 	register long ret asm ("x0");
39*4882a593Smuzhiyun 	register long nr asm("x8") = __NR_clock_gettime;
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun 	asm volatile(
42*4882a593Smuzhiyun 	"       svc #0\n"
43*4882a593Smuzhiyun 	: "=r" (ret)
44*4882a593Smuzhiyun 	: "r" (clkid), "r" (ts), "r" (nr)
45*4882a593Smuzhiyun 	: "memory");
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	return ret;
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun static __always_inline
clock_getres_fallback(clockid_t _clkid,struct __kernel_timespec * _ts)51*4882a593Smuzhiyun int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
52*4882a593Smuzhiyun {
53*4882a593Smuzhiyun 	register struct __kernel_timespec *ts asm("x1") = _ts;
54*4882a593Smuzhiyun 	register clockid_t clkid asm("x0") = _clkid;
55*4882a593Smuzhiyun 	register long ret asm ("x0");
56*4882a593Smuzhiyun 	register long nr asm("x8") = __NR_clock_getres;
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 	asm volatile(
59*4882a593Smuzhiyun 	"       svc #0\n"
60*4882a593Smuzhiyun 	: "=r" (ret)
61*4882a593Smuzhiyun 	: "r" (clkid), "r" (ts), "r" (nr)
62*4882a593Smuzhiyun 	: "memory");
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 	return ret;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun 
__arch_get_hw_counter(s32 clock_mode,const struct vdso_data * vd)67*4882a593Smuzhiyun static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
68*4882a593Smuzhiyun 						 const struct vdso_data *vd)
69*4882a593Smuzhiyun {
70*4882a593Smuzhiyun 	u64 res;
71*4882a593Smuzhiyun 
72*4882a593Smuzhiyun 	/*
73*4882a593Smuzhiyun 	 * Core checks for mode already, so this raced against a concurrent
74*4882a593Smuzhiyun 	 * update. Return something. Core will do another round and then
75*4882a593Smuzhiyun 	 * see the mode change and fallback to the syscall.
76*4882a593Smuzhiyun 	 */
77*4882a593Smuzhiyun 	if (clock_mode == VDSO_CLOCKMODE_NONE)
78*4882a593Smuzhiyun 		return 0;
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun 	/*
81*4882a593Smuzhiyun 	 * This isb() is required to prevent that the counter value
82*4882a593Smuzhiyun 	 * is speculated.
83*4882a593Smuzhiyun 	 */
84*4882a593Smuzhiyun 	isb();
85*4882a593Smuzhiyun 	asm volatile("mrs %0, cntvct_el0" : "=r" (res) :: "memory");
86*4882a593Smuzhiyun 	arch_counter_enforce_ordering(res);
87*4882a593Smuzhiyun 
88*4882a593Smuzhiyun 	return res;
89*4882a593Smuzhiyun }
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun static __always_inline
__arch_get_vdso_data(void)92*4882a593Smuzhiyun const struct vdso_data *__arch_get_vdso_data(void)
93*4882a593Smuzhiyun {
94*4882a593Smuzhiyun 	return _vdso_data;
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun 
97*4882a593Smuzhiyun #ifdef CONFIG_TIME_NS
98*4882a593Smuzhiyun static __always_inline
__arch_get_timens_vdso_data(void)99*4882a593Smuzhiyun const struct vdso_data *__arch_get_timens_vdso_data(void)
100*4882a593Smuzhiyun {
101*4882a593Smuzhiyun 	return _timens_data;
102*4882a593Smuzhiyun }
103*4882a593Smuzhiyun #endif
104*4882a593Smuzhiyun 
105*4882a593Smuzhiyun #endif /* !__ASSEMBLY__ */
106*4882a593Smuzhiyun 
107*4882a593Smuzhiyun #endif /* __ASM_VDSO_GETTIMEOFDAY_H */
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