xref: /linux/arch/powerpc/kernel/vdso/gettimeofday.S (revision 7340c6df49df1b261892d287444c255d0a378063)
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#ifdef __powerpc64__
42	bl		CFUNC(DOTSYM(\funct))
43#else
44	bl		\funct
45#endif
46	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
47#ifdef __powerpc64__
48	PPC_LL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
49  .cfi_restore r2
50#endif
51	.ifeq	\call_time
52	cmpwi		r3, 0
53	.endif
54	mtlr		r0
55	addi		r1, r1, 2 * PPC_MIN_STKFRM
56  .cfi_restore lr
57  .cfi_def_cfa_offset 0
58	crclr		so
59	.ifeq	\call_time
60	beqlr+
61	crset		so
62	neg		r3, r3
63	.endif
64	blr
65  .cfi_endproc
66.endm
67
68	.text
69/*
70 * Exact prototype of gettimeofday
71 *
72 * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz);
73 *
74 */
75V_FUNCTION_BEGIN(__kernel_gettimeofday)
76	cvdso_call __c_kernel_gettimeofday
77V_FUNCTION_END(__kernel_gettimeofday)
78
79/*
80 * Exact prototype of clock_gettime()
81 *
82 * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp);
83 *
84 */
85V_FUNCTION_BEGIN(__kernel_clock_gettime)
86	cvdso_call __c_kernel_clock_gettime
87V_FUNCTION_END(__kernel_clock_gettime)
88
89/*
90 * Exact prototype of clock_gettime64()
91 *
92 * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
93 *
94 */
95#ifndef __powerpc64__
96V_FUNCTION_BEGIN(__kernel_clock_gettime64)
97	cvdso_call __c_kernel_clock_gettime64
98V_FUNCTION_END(__kernel_clock_gettime64)
99#endif
100
101/*
102 * Exact prototype of clock_getres()
103 *
104 * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res);
105 *
106 */
107V_FUNCTION_BEGIN(__kernel_clock_getres)
108	cvdso_call __c_kernel_clock_getres
109V_FUNCTION_END(__kernel_clock_getres)
110
111
112/*
113 * Exact prototype of time()
114 *
115 * time_t time(time *t);
116 *
117 */
118V_FUNCTION_BEGIN(__kernel_time)
119	cvdso_call __c_kernel_time call_time=1
120V_FUNCTION_END(__kernel_time)
121
122/* Routines for restoring integer registers, called by the compiler.  */
123/* Called with r11 pointing to the stack header word of the caller of the */
124/* function, just beyond the end of the integer restore area.  */
125#ifndef __powerpc64__
126_GLOBAL(_restgpr_31_x)
127_GLOBAL(_rest32gpr_31_x)
128	lwz	r0,4(r11)
129	lwz	r31,-4(r11)
130	mtlr	r0
131	mr	r1,r11
132	blr
133#endif
134