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
18 extern struct vdso_data *__get_datapage(void);
19
20 static __always_inline int gettimeofday_fallback(
21 struct __kernel_old_timeval *_tv,
22 struct timezone *_tz)
23 {
24 register struct timezone *tz asm("r1") = _tz;
25 register struct __kernel_old_timeval *tv asm("r0") = _tv;
26 register long ret asm ("r0");
27 register long nr asm("r7") = __NR_gettimeofday;
28
29 asm volatile(
30 " swi #0\n"
31 : "=r" (ret)
32 : "r" (tv), "r" (tz), "r" (nr)
33 : "memory");
34
35 return ret;
36 }
37
38 static __always_inline long clock_gettime_fallback(
39 clockid_t _clkid,
40 struct __kernel_timespec *_ts)
41 {
42 register struct __kernel_timespec *ts asm("r1") = _ts;
43 register clockid_t clkid asm("r0") = _clkid;
44 register long ret asm ("r0");
45 register long nr asm("r7") = __NR_clock_gettime64;
46
47 asm volatile(
48 " swi #0\n"
49 : "=r" (ret)
50 : "r" (clkid), "r" (ts), "r" (nr)
51 : "memory");
52
53 return ret;
54 }
55
56 static __always_inline long clock_gettime32_fallback(
57 clockid_t _clkid,
58 struct old_timespec32 *_ts)
59 {
60 register struct old_timespec32 *ts asm("r1") = _ts;
61 register clockid_t clkid asm("r0") = _clkid;
62 register long ret asm ("r0");
63 register long nr asm("r7") = __NR_clock_gettime;
64
65 asm volatile(
66 " swi #0\n"
67 : "=r" (ret)
68 : "r" (clkid), "r" (ts), "r" (nr)
69 : "memory");
70
71 return ret;
72 }
73
74 static __always_inline int clock_getres_fallback(
75 clockid_t _clkid,
76 struct __kernel_timespec *_ts)
77 {
78 register struct __kernel_timespec *ts asm("r1") = _ts;
79 register clockid_t clkid asm("r0") = _clkid;
80 register long ret asm ("r0");
81 register long nr asm("r7") = __NR_clock_getres_time64;
82
83 asm volatile(
84 " swi #0\n"
85 : "=r" (ret)
86 : "r" (clkid), "r" (ts), "r" (nr)
87 : "memory");
88
89 return ret;
90 }
91
92 static __always_inline int clock_getres32_fallback(
93 clockid_t _clkid,
94 struct old_timespec32 *_ts)
95 {
96 register struct old_timespec32 *ts asm("r1") = _ts;
97 register clockid_t clkid asm("r0") = _clkid;
98 register long ret asm ("r0");
99 register long nr asm("r7") = __NR_clock_getres;
100
101 asm volatile(
102 " swi #0\n"
103 : "=r" (ret)
104 : "r" (clkid), "r" (ts), "r" (nr)
105 : "memory");
106
107 return ret;
108 }
109
110 static inline bool arm_vdso_hres_capable(void)
111 {
112 return IS_ENABLED(CONFIG_ARM_ARCH_TIMER);
113 }
114 #define __arch_vdso_hres_capable arm_vdso_hres_capable
115
116 static __always_inline u64 __arch_get_hw_counter(int clock_mode,
117 const struct vdso_data *vd)
118 {
119 #ifdef CONFIG_ARM_ARCH_TIMER
120 u64 cycle_now;
121
122 /*
123 * Core checks for mode already, so this raced against a concurrent
124 * update. Return something. Core will do another round and then
125 * see the mode change and fallback to the syscall.
126 */
127 if (clock_mode == VDSO_CLOCKMODE_NONE)
128 return 0;
129
130 isb();
131 cycle_now = read_sysreg(CNTVCT);
132
133 return cycle_now;
134 #else
135 /* Make GCC happy. This is compiled out anyway */
136 return 0;
137 #endif
138 }
139
140 static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
141 {
142 return __get_datapage();
143 }
144
145 #endif /* !__ASSEMBLY__ */
146
147 #endif /* __ASM_VDSO_GETTIMEOFDAY_H */
148
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