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	mflr		r0
26  .cfi_register lr, r0
27	PPC_STLU	r1, -PPC_MIN_STKFRM(r1)
28	PPC_STL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
29#ifdef __powerpc64__
30	PPC_STL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
31#endif
32	get_datapage	r5
33	.ifeq	\call_time
34	addi		r5, r5, VDSO_DATA_OFFSET
35	.else
36	addi		r4, r5, VDSO_DATA_OFFSET
37	.endif
38	bl		DOTSYM(\funct)
39	PPC_LL		r0, PPC_MIN_STKFRM + PPC_LR_STKOFF(r1)
40#ifdef __powerpc64__
41	PPC_LL		r2, PPC_MIN_STKFRM + STK_GOT(r1)
42#endif
43	.ifeq	\call_time
44	cmpwi		r3, 0
45	.endif
46	mtlr		r0
47  .cfi_restore lr
48	addi		r1, r1, 2 * PPC_MIN_STKFRM
49	crclr		so
50	.ifeq	\call_time
51	beqlr+
52	crset		so
53	neg		r3, r3
54	.endif
55	blr
56  .cfi_endproc
57.endm
58
59	.text
60/*
61 * Exact prototype of gettimeofday
62 *
63 * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz);
64 *
65 */
66V_FUNCTION_BEGIN(__kernel_gettimeofday)
67	cvdso_call __c_kernel_gettimeofday
68V_FUNCTION_END(__kernel_gettimeofday)
69
70/*
71 * Exact prototype of clock_gettime()
72 *
73 * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp);
74 *
75 */
76V_FUNCTION_BEGIN(__kernel_clock_gettime)
77	cvdso_call __c_kernel_clock_gettime
78V_FUNCTION_END(__kernel_clock_gettime)
79
80/*
81 * Exact prototype of clock_gettime64()
82 *
83 * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
84 *
85 */
86#ifndef __powerpc64__
87V_FUNCTION_BEGIN(__kernel_clock_gettime64)
88	cvdso_call __c_kernel_clock_gettime64
89V_FUNCTION_END(__kernel_clock_gettime64)
90#endif
91
92/*
93 * Exact prototype of clock_getres()
94 *
95 * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res);
96 *
97 */
98V_FUNCTION_BEGIN(__kernel_clock_getres)
99	cvdso_call __c_kernel_clock_getres
100V_FUNCTION_END(__kernel_clock_getres)
101
102
103/*
104 * Exact prototype of time()
105 *
106 * time_t time(time *t);
107 *
108 */
109V_FUNCTION_BEGIN(__kernel_time)
110	cvdso_call __c_kernel_time call_time=1
111V_FUNCTION_END(__kernel_time)
112
113/* Routines for restoring integer registers, called by the compiler.  */
114/* Called with r11 pointing to the stack header word of the caller of the */
115/* function, just beyond the end of the integer restore area.  */
116#ifndef __powerpc64__
117_GLOBAL(_restgpr_31_x)
118_GLOBAL(_rest32gpr_31_x)
119	lwz	r0,4(r11)
120	lwz	r31,-4(r11)
121	mtlr	r0
122	mr	r1,r11
123	blr
124#endif
125