xref: /linux/arch/powerpc/kernel/vdso/gettimeofday.S (revision 55d0969c451159cff86949b38c39171cab962069)
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	get_datapage	r5
36	.ifeq	\call_time
37	addi		r5, r5, VDSO_DATA_OFFSET
38	.else
39	addi		r4, r5, VDSO_DATA_OFFSET
40	.endif
41	bl		CFUNC(DOTSYM(\funct))
42	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
43#ifdef __powerpc64__
44	PPC_LL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
45  .cfi_restore r2
46#endif
47	.ifeq	\call_time
48	cmpwi		r3, 0
49	.endif
50	mtlr		r0
51	addi		r1, r1, 2 * PPC_MIN_STKFRM
52  .cfi_restore lr
53  .cfi_def_cfa_offset 0
54	crclr		so
55	.ifeq	\call_time
56	beqlr+
57	crset		so
58	neg		r3, r3
59	.endif
60	blr
61  .cfi_endproc
62.endm
63
64	.text
65/*
66 * Exact prototype of gettimeofday
67 *
68 * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz);
69 *
70 */
71V_FUNCTION_BEGIN(__kernel_gettimeofday)
72	cvdso_call __c_kernel_gettimeofday
73V_FUNCTION_END(__kernel_gettimeofday)
74
75/*
76 * Exact prototype of clock_gettime()
77 *
78 * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp);
79 *
80 */
81V_FUNCTION_BEGIN(__kernel_clock_gettime)
82	cvdso_call __c_kernel_clock_gettime
83V_FUNCTION_END(__kernel_clock_gettime)
84
85/*
86 * Exact prototype of clock_gettime64()
87 *
88 * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
89 *
90 */
91#ifndef __powerpc64__
92V_FUNCTION_BEGIN(__kernel_clock_gettime64)
93	cvdso_call __c_kernel_clock_gettime64
94V_FUNCTION_END(__kernel_clock_gettime64)
95#endif
96
97/*
98 * Exact prototype of clock_getres()
99 *
100 * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res);
101 *
102 */
103V_FUNCTION_BEGIN(__kernel_clock_getres)
104	cvdso_call __c_kernel_clock_getres
105V_FUNCTION_END(__kernel_clock_getres)
106
107
108/*
109 * Exact prototype of time()
110 *
111 * time_t time(time *t);
112 *
113 */
114V_FUNCTION_BEGIN(__kernel_time)
115	cvdso_call __c_kernel_time call_time=1
116V_FUNCTION_END(__kernel_time)
117