1/*
  2 * Copyright (C) 2018 ARM Limited
  3 * Copyright (C) 2015 Imagination Technologies
  4 * Author: Alex Smith <alex.smith@imgtec.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify it
  7 * under the terms of the GNU General Public License as published by the
  8 * Free Software Foundation;  either version 2 of the  License, or (at your
  9 * option) any later version.
 10 */
 11#ifndef __ASM_VDSO_GETTIMEOFDAY_H
 12#define __ASM_VDSO_GETTIMEOFDAY_H
 13
 14#ifndef __ASSEMBLY__
 15
 16#include <asm/vdso/vdso.h>
 17#include <asm/clocksource.h>
 18#include <asm/unistd.h>
 19#include <asm/vdso.h>
 20
 21#define VDSO_HAS_CLOCK_GETRES		1
 22
 23static __always_inline long gettimeofday_fallback(
 24				struct __kernel_old_timeval *_tv,
 25				struct timezone *_tz)
 26{
 27	register struct timezone *tz asm("a1") = _tz;
 28	register struct __kernel_old_timeval *tv asm("a0") = _tv;
 29	register long ret asm("v0");
 30	register long nr asm("v0") = __NR_gettimeofday;
 31	register long error asm("a3");
 32
 33	asm volatile(
 34	"       syscall\n"
 35	: "=r" (ret), "=r" (error)
 36	: "r" (tv), "r" (tz), "r" (nr)
 37	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
 38	  "$14", "$15", "$24", "$25", "hi", "lo", "memory");
 39
 40	return error ? -ret : ret;
 41}
 42
 43static __always_inline long clock_gettime_fallback(
 44					clockid_t _clkid,
 45					struct __kernel_timespec *_ts)
 46{
 47	register struct __kernel_timespec *ts asm("a1") = _ts;
 48	register clockid_t clkid asm("a0") = _clkid;
 49	register long ret asm("v0");
 50#if _MIPS_SIM == _MIPS_SIM_ABI64
 51	register long nr asm("v0") = __NR_clock_gettime;
 52#else
 53	register long nr asm("v0") = __NR_clock_gettime64;
 54#endif
 55	register long error asm("a3");
 56
 57	asm volatile(
 58	"       syscall\n"
 59	: "=r" (ret), "=r" (error)
 60	: "r" (clkid), "r" (ts), "r" (nr)
 61	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
 62	  "$14", "$15", "$24", "$25", "hi", "lo", "memory");
 63
 64	return error ? -ret : ret;
 65}
 66
 67static __always_inline int clock_getres_fallback(
 68					clockid_t _clkid,
 69					struct __kernel_timespec *_ts)
 70{
 71	register struct __kernel_timespec *ts asm("a1") = _ts;
 72	register clockid_t clkid asm("a0") = _clkid;
 73	register long ret asm("v0");
 74#if _MIPS_SIM == _MIPS_SIM_ABI64
 75	register long nr asm("v0") = __NR_clock_getres;
 76#else
 77	register long nr asm("v0") = __NR_clock_getres_time64;
 78#endif
 79	register long error asm("a3");
 80
 81	asm volatile(
 82	"       syscall\n"
 83	: "=r" (ret), "=r" (error)
 84	: "r" (clkid), "r" (ts), "r" (nr)
 85	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
 86	  "$14", "$15", "$24", "$25", "hi", "lo", "memory");
 87
 88	return error ? -ret : ret;
 89}
 90
 91#if _MIPS_SIM != _MIPS_SIM_ABI64
 92
 93static __always_inline long clock_gettime32_fallback(
 94					clockid_t _clkid,
 95					struct old_timespec32 *_ts)
 96{
 97	register struct old_timespec32 *ts asm("a1") = _ts;
 98	register clockid_t clkid asm("a0") = _clkid;
 99	register long ret asm("v0");
100	register long nr asm("v0") = __NR_clock_gettime;
101	register long error asm("a3");
102
103	asm volatile(
104	"       syscall\n"
105	: "=r" (ret), "=r" (error)
106	: "r" (clkid), "r" (ts), "r" (nr)
107	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
108	  "$14", "$15", "$24", "$25", "hi", "lo", "memory");
109
110	return error ? -ret : ret;
111}
112
113static __always_inline int clock_getres32_fallback(
114					clockid_t _clkid,
115					struct old_timespec32 *_ts)
116{
117	register struct old_timespec32 *ts asm("a1") = _ts;
118	register clockid_t clkid asm("a0") = _clkid;
119	register long ret asm("v0");
120	register long nr asm("v0") = __NR_clock_getres;
121	register long error asm("a3");
122
123	asm volatile(
124	"       syscall\n"
125	: "=r" (ret), "=r" (error)
126	: "r" (clkid), "r" (ts), "r" (nr)
127	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
128	  "$14", "$15", "$24", "$25", "hi", "lo", "memory");
129
130	return error ? -ret : ret;
131}
132#endif
133
134#ifdef CONFIG_CSRC_R4K
135
136static __always_inline u64 read_r4k_count(void)
137{
138	unsigned int count;
139
140	__asm__ __volatile__(
141	"	.set push\n"
142	"	.set mips32r2\n"
143	"	rdhwr	%0, $2\n"
144	"	.set pop\n"
145	: "=r" (count));
146
147	return count;
148}
149
150#endif
151
152#ifdef CONFIG_CLKSRC_MIPS_GIC
153
154static __always_inline u64 read_gic_count(const struct vdso_data *data)
155{
156	void __iomem *gic = get_gic(data);
157	u32 hi, hi2, lo;
158
159	do {
160		hi = __raw_readl(gic + sizeof(lo));
161		lo = __raw_readl(gic);
162		hi2 = __raw_readl(gic + sizeof(lo));
163	} while (hi2 != hi);
164
165	return (((u64)hi) << 32) + lo;
166}
167
168#endif
169
170static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
171						 const struct vdso_data *vd)
172{
173#ifdef CONFIG_CSRC_R4K
174	if (clock_mode == VDSO_CLOCKMODE_R4K)
175		return read_r4k_count();
176#endif
177#ifdef CONFIG_CLKSRC_MIPS_GIC
178	if (clock_mode == VDSO_CLOCKMODE_GIC)
179		return read_gic_count(vd);
180#endif
181	/*
182	 * Core checks mode already. So this raced against a concurrent
183	 * update. Return something. Core will do another round see the
184	 * change and fallback to syscall.
185	 */
186	return 0;
187}
188
189static inline bool mips_vdso_hres_capable(void)
190{
191	return IS_ENABLED(CONFIG_CSRC_R4K) ||
192	       IS_ENABLED(CONFIG_CLKSRC_MIPS_GIC);
193}
194#define __arch_vdso_hres_capable mips_vdso_hres_capable
195
196static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
197{
198	return get_vdso_data();
199}
200
201#endif /* !__ASSEMBLY__ */
202
203#endif /* __ASM_VDSO_GETTIMEOFDAY_H */