xref: /linux/arch/powerpc/kernel/vdso/gettimeofday.S (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Userland implementation of gettimeofday() for processes
4 * for use in the vDSO
5 *
6 * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org,
7 *                    IBM Corp.
8 */
9#include <asm/processor.h>
10#include <asm/ppc_asm.h>
11#include <asm/vdso.h>
12#include <asm/vdso_datapage.h>
13#include <asm/asm-offsets.h>
14#include <asm/unistd.h>
15
16/*
17 * The macro sets two stack frames, one for the caller and one for the callee
18 * because there are no requirement for the caller to set a stack frame when
19 * calling VDSO so it may have omitted to set one, especially on PPC64
20 */
21
22.macro cvdso_call funct call_time=0
23  .cfi_startproc
24	PPC_STLU	r1, -PPC_MIN_STKFRM(r1)
25  .cfi_adjust_cfa_offset PPC_MIN_STKFRM
26	mflr		r0
27	PPC_STLU	r1, -PPC_MIN_STKFRM(r1)
28  .cfi_adjust_cfa_offset PPC_MIN_STKFRM
29	PPC_STL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
30  .cfi_rel_offset lr, PPC_MIN_STKFRM + PPC_LR_STKOFF
31#ifdef __powerpc64__
32	PPC_STL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
33  .cfi_rel_offset r2, PPC_MIN_STKFRM + STK_GOT
34#endif
35	.ifeq	\call_time
36		get_datapage	r5 VDSO_DATA_OFFSET
37	.else
38		get_datapage	r4 VDSO_DATA_OFFSET
39	.endif
40	bl		CFUNC(DOTSYM(\funct))
41	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
42#ifdef __powerpc64__
43	PPC_LL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
44  .cfi_restore r2
45#endif
46	.ifeq	\call_time
47	cmpwi		r3, 0
48	.endif
49	mtlr		r0
50	addi		r1, r1, 2 * PPC_MIN_STKFRM
51  .cfi_restore lr
52  .cfi_def_cfa_offset 0
53	crclr		so
54	.ifeq	\call_time
55	beqlr+
56	crset		so
57	neg		r3, r3
58	.endif
59	blr
60  .cfi_endproc
61.endm
62
63	.text
64/*
65 * Exact prototype of gettimeofday
66 *
67 * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz);
68 *
69 */
70V_FUNCTION_BEGIN(__kernel_gettimeofday)
71	cvdso_call __c_kernel_gettimeofday
72V_FUNCTION_END(__kernel_gettimeofday)
73
74/*
75 * Exact prototype of clock_gettime()
76 *
77 * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp);
78 *
79 */
80V_FUNCTION_BEGIN(__kernel_clock_gettime)
81	cvdso_call __c_kernel_clock_gettime
82V_FUNCTION_END(__kernel_clock_gettime)
83
84/*
85 * Exact prototype of clock_gettime64()
86 *
87 * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
88 *
89 */
90#ifndef __powerpc64__
91V_FUNCTION_BEGIN(__kernel_clock_gettime64)
92	cvdso_call __c_kernel_clock_gettime64
93V_FUNCTION_END(__kernel_clock_gettime64)
94#endif
95
96/*
97 * Exact prototype of clock_getres()
98 *
99 * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res);
100 *
101 */
102V_FUNCTION_BEGIN(__kernel_clock_getres)
103	cvdso_call __c_kernel_clock_getres
104V_FUNCTION_END(__kernel_clock_getres)
105
106
107/*
108 * Exact prototype of time()
109 *
110 * time_t time(time *t);
111 *
112 */
113V_FUNCTION_BEGIN(__kernel_time)
114	cvdso_call __c_kernel_time call_time=1
115V_FUNCTION_END(__kernel_time)
116