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
 18extern struct vdso_data *__get_datapage(void);
 19
 20static __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
 38static __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
 56static __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
 74static __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
 92static __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
110static 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
116static __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
140static __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 */