1a7f71a2cSVincenzo Frascino /* SPDX-License-Identifier: GPL-2.0 */
2a7f71a2cSVincenzo Frascino /*
3a7f71a2cSVincenzo Frascino * Copyright (C) 2018 ARM Limited
4a7f71a2cSVincenzo Frascino */
5a7f71a2cSVincenzo Frascino #ifndef __ASM_VDSO_GETTIMEOFDAY_H
6a7f71a2cSVincenzo Frascino #define __ASM_VDSO_GETTIMEOFDAY_H
7a7f71a2cSVincenzo Frascino
8a7f71a2cSVincenzo Frascino #ifndef __ASSEMBLY__
9a7f71a2cSVincenzo Frascino
10002dff36SWill Deacon #include <asm/barrier.h>
11a7f71a2cSVincenzo Frascino #include <asm/unistd.h>
125340e873SVincenzo Frascino #include <asm/errno.h>
13a7f71a2cSVincenzo Frascino
14a7f71a2cSVincenzo Frascino #include <asm/vdso/compat_barrier.h>
15a7f71a2cSVincenzo Frascino
16a7f71a2cSVincenzo Frascino #define VDSO_HAS_CLOCK_GETRES 1
17a7f71a2cSVincenzo Frascino
183b5584afSVincenzo Frascino #define BUILD_VDSO32 1
1933a58980SThomas Gleixner
20a7f71a2cSVincenzo Frascino static __always_inline
gettimeofday_fallback(struct __kernel_old_timeval * _tv,struct timezone * _tz)21a7f71a2cSVincenzo Frascino int gettimeofday_fallback(struct __kernel_old_timeval *_tv,
22a7f71a2cSVincenzo Frascino struct timezone *_tz)
23a7f71a2cSVincenzo Frascino {
24a7f71a2cSVincenzo Frascino register struct timezone *tz asm("r1") = _tz;
25a7f71a2cSVincenzo Frascino register struct __kernel_old_timeval *tv asm("r0") = _tv;
26a7f71a2cSVincenzo Frascino register long ret asm ("r0");
27a7f71a2cSVincenzo Frascino register long nr asm("r7") = __NR_compat_gettimeofday;
28a7f71a2cSVincenzo Frascino
29a7f71a2cSVincenzo Frascino asm volatile(
30a7f71a2cSVincenzo Frascino " swi #0\n"
31a7f71a2cSVincenzo Frascino : "=r" (ret)
32a7f71a2cSVincenzo Frascino : "r" (tv), "r" (tz), "r" (nr)
33a7f71a2cSVincenzo Frascino : "memory");
34a7f71a2cSVincenzo Frascino
35a7f71a2cSVincenzo Frascino return ret;
36a7f71a2cSVincenzo Frascino }
37a7f71a2cSVincenzo Frascino
38a7f71a2cSVincenzo Frascino static __always_inline
clock_gettime_fallback(clockid_t _clkid,struct __kernel_timespec * _ts)39a7f71a2cSVincenzo Frascino long clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
40a7f71a2cSVincenzo Frascino {
41a7f71a2cSVincenzo Frascino register struct __kernel_timespec *ts asm("r1") = _ts;
42a7f71a2cSVincenzo Frascino register clockid_t clkid asm("r0") = _clkid;
43a7f71a2cSVincenzo Frascino register long ret asm ("r0");
44a7f71a2cSVincenzo Frascino register long nr asm("r7") = __NR_compat_clock_gettime64;
45a7f71a2cSVincenzo Frascino
46a7f71a2cSVincenzo Frascino asm volatile(
47a7f71a2cSVincenzo Frascino " swi #0\n"
48a7f71a2cSVincenzo Frascino : "=r" (ret)
49a7f71a2cSVincenzo Frascino : "r" (clkid), "r" (ts), "r" (nr)
50a7f71a2cSVincenzo Frascino : "memory");
51a7f71a2cSVincenzo Frascino
52a7f71a2cSVincenzo Frascino return ret;
53a7f71a2cSVincenzo Frascino }
54a7f71a2cSVincenzo Frascino
55a7f71a2cSVincenzo Frascino static __always_inline
clock_gettime32_fallback(clockid_t _clkid,struct old_timespec32 * _ts)5633a58980SThomas Gleixner long clock_gettime32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
5733a58980SThomas Gleixner {
5833a58980SThomas Gleixner register struct old_timespec32 *ts asm("r1") = _ts;
5933a58980SThomas Gleixner register clockid_t clkid asm("r0") = _clkid;
6033a58980SThomas Gleixner register long ret asm ("r0");
6133a58980SThomas Gleixner register long nr asm("r7") = __NR_compat_clock_gettime;
6233a58980SThomas Gleixner
6333a58980SThomas Gleixner asm volatile(
6433a58980SThomas Gleixner " swi #0\n"
6533a58980SThomas Gleixner : "=r" (ret)
6633a58980SThomas Gleixner : "r" (clkid), "r" (ts), "r" (nr)
6733a58980SThomas Gleixner : "memory");
6833a58980SThomas Gleixner
6933a58980SThomas Gleixner return ret;
7033a58980SThomas Gleixner }
7133a58980SThomas Gleixner
7233a58980SThomas Gleixner static __always_inline
clock_getres_fallback(clockid_t _clkid,struct __kernel_timespec * _ts)73a7f71a2cSVincenzo Frascino int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
74a7f71a2cSVincenzo Frascino {
75a7f71a2cSVincenzo Frascino register struct __kernel_timespec *ts asm("r1") = _ts;
76a7f71a2cSVincenzo Frascino register clockid_t clkid asm("r0") = _clkid;
77a7f71a2cSVincenzo Frascino register long ret asm ("r0");
78a7f71a2cSVincenzo Frascino register long nr asm("r7") = __NR_compat_clock_getres_time64;
79a7f71a2cSVincenzo Frascino
80a7f71a2cSVincenzo Frascino asm volatile(
81a7f71a2cSVincenzo Frascino " swi #0\n"
82a7f71a2cSVincenzo Frascino : "=r" (ret)
83a7f71a2cSVincenzo Frascino : "r" (clkid), "r" (ts), "r" (nr)
84a7f71a2cSVincenzo Frascino : "memory");
85a7f71a2cSVincenzo Frascino
86a7f71a2cSVincenzo Frascino return ret;
87a7f71a2cSVincenzo Frascino }
88a7f71a2cSVincenzo Frascino
8933a58980SThomas Gleixner static __always_inline
clock_getres32_fallback(clockid_t _clkid,struct old_timespec32 * _ts)9033a58980SThomas Gleixner int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
9133a58980SThomas Gleixner {
9233a58980SThomas Gleixner register struct old_timespec32 *ts asm("r1") = _ts;
9333a58980SThomas Gleixner register clockid_t clkid asm("r0") = _clkid;
9433a58980SThomas Gleixner register long ret asm ("r0");
9533a58980SThomas Gleixner register long nr asm("r7") = __NR_compat_clock_getres;
9633a58980SThomas Gleixner
9733a58980SThomas Gleixner asm volatile(
9833a58980SThomas Gleixner " swi #0\n"
9933a58980SThomas Gleixner : "=r" (ret)
10033a58980SThomas Gleixner : "r" (clkid), "r" (ts), "r" (nr)
10133a58980SThomas Gleixner : "memory");
10233a58980SThomas Gleixner
10333a58980SThomas Gleixner return ret;
10433a58980SThomas Gleixner }
10533a58980SThomas Gleixner
__arch_get_hw_counter(s32 clock_mode,const struct vdso_data * vd)1064c5a116aSThomas Gleixner static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
1074c5a116aSThomas Gleixner const struct vdso_data *vd)
108a7f71a2cSVincenzo Frascino {
109a7f71a2cSVincenzo Frascino u64 res;
110a7f71a2cSVincenzo Frascino
1116241c4dcSVincenzo Frascino /*
1125e3c6a31SThomas Gleixner * Core checks for mode already, so this raced against a concurrent
1135e3c6a31SThomas Gleixner * update. Return something. Core will do another round and then
1145e3c6a31SThomas Gleixner * see the mode change and fallback to the syscall.
1156241c4dcSVincenzo Frascino */
11697884ca8SMarc Zyngier if (clock_mode != VDSO_CLOCKMODE_ARCHTIMER)
1175e3c6a31SThomas Gleixner return 0;
1186241c4dcSVincenzo Frascino
1196241c4dcSVincenzo Frascino /*
1206241c4dcSVincenzo Frascino * This isb() is required to prevent that the counter value
1216241c4dcSVincenzo Frascino * is speculated.
1226241c4dcSVincenzo Frascino */
123a7f71a2cSVincenzo Frascino isb();
124a7f71a2cSVincenzo Frascino asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (res));
1256241c4dcSVincenzo Frascino /*
1266241c4dcSVincenzo Frascino * This isb() is required to prevent that the seq lock is
1276241c4dcSVincenzo Frascino * speculated.
1286241c4dcSVincenzo Frascino */
1296241c4dcSVincenzo Frascino isb();
130a7f71a2cSVincenzo Frascino
131a7f71a2cSVincenzo Frascino return res;
132a7f71a2cSVincenzo Frascino }
133a7f71a2cSVincenzo Frascino
__arch_get_vdso_data(void)134a7f71a2cSVincenzo Frascino static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
135a7f71a2cSVincenzo Frascino {
136a7f71a2cSVincenzo Frascino const struct vdso_data *ret;
137a7f71a2cSVincenzo Frascino
138a7f71a2cSVincenzo Frascino /*
139a7f71a2cSVincenzo Frascino * This simply puts &_vdso_data into ret. The reason why we don't use
140a7f71a2cSVincenzo Frascino * `ret = _vdso_data` is that the compiler tends to optimise this in a
141a7f71a2cSVincenzo Frascino * very suboptimal way: instead of keeping &_vdso_data in a register,
142a7f71a2cSVincenzo Frascino * it goes through a relocation almost every time _vdso_data must be
143a7f71a2cSVincenzo Frascino * accessed (even in subfunctions). This is both time and space
144a7f71a2cSVincenzo Frascino * consuming: each relocation uses a word in the code section, and it
145a7f71a2cSVincenzo Frascino * has to be loaded at runtime.
146a7f71a2cSVincenzo Frascino *
147a7f71a2cSVincenzo Frascino * This trick hides the assignment from the compiler. Since it cannot
148a7f71a2cSVincenzo Frascino * track where the pointer comes from, it will only use one relocation
149a7f71a2cSVincenzo Frascino * where __arch_get_vdso_data() is called, and then keep the result in
150a7f71a2cSVincenzo Frascino * a register.
151a7f71a2cSVincenzo Frascino */
152a7f71a2cSVincenzo Frascino asm volatile("mov %0, %1" : "=r"(ret) : "r"(_vdso_data));
153a7f71a2cSVincenzo Frascino
154a7f71a2cSVincenzo Frascino return ret;
155a7f71a2cSVincenzo Frascino }
156a7f71a2cSVincenzo Frascino
1573503d56cSAndrei Vagin #ifdef CONFIG_TIME_NS
158*808094fcSChristophe Leroy static __always_inline
__arch_get_timens_vdso_data(const struct vdso_data * vd)159*808094fcSChristophe Leroy const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
1603503d56cSAndrei Vagin {
1613503d56cSAndrei Vagin const struct vdso_data *ret;
1623503d56cSAndrei Vagin
1633503d56cSAndrei Vagin /* See __arch_get_vdso_data(). */
1643503d56cSAndrei Vagin asm volatile("mov %0, %1" : "=r"(ret) : "r"(_timens_data));
1653503d56cSAndrei Vagin
1663503d56cSAndrei Vagin return ret;
1673503d56cSAndrei Vagin }
1683503d56cSAndrei Vagin #endif
1693503d56cSAndrei Vagin
vdso_clocksource_ok(const struct vdso_data * vd)17097884ca8SMarc Zyngier static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
17197884ca8SMarc Zyngier {
17297884ca8SMarc Zyngier return vd->clock_mode == VDSO_CLOCKMODE_ARCHTIMER;
17397884ca8SMarc Zyngier }
17497884ca8SMarc Zyngier #define vdso_clocksource_ok vdso_clocksource_ok
17597884ca8SMarc Zyngier
176a7f71a2cSVincenzo Frascino #endif /* !__ASSEMBLY__ */
177a7f71a2cSVincenzo Frascino
178a7f71a2cSVincenzo Frascino #endif /* __ASM_VDSO_GETTIMEOFDAY_H */
179