1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Userland implementation of clock_getres() for 32 bits processes in a
4 * s390 kernel for use in the vDSO
5 *
6 *  Copyright IBM Corp. 2008
7 *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
8 */
9#include <asm/vdso.h>
10#include <asm/asm-offsets.h>
11#include <asm/unistd.h>
12#include <asm/dwarf.h>
13
14	.text
15	.align 4
16	.globl __kernel_clock_getres
17	.type  __kernel_clock_getres,@function
18__kernel_clock_getres:
19	CFI_STARTPROC
20	basr	%r1,0
21	la	%r1,4f-.(%r1)
22	chi	%r2,__CLOCK_REALTIME
23	je	0f
24	chi	%r2,__CLOCK_MONOTONIC
25	je	0f
26	la	%r1,5f-4f(%r1)
27	chi	%r2,__CLOCK_REALTIME_COARSE
28	je	0f
29	chi	%r2,__CLOCK_MONOTONIC_COARSE
30	jne	3f
310:	ltr	%r3,%r3
32	jz	2f				/* res == NULL */
331:	l	%r0,0(%r1)
34	xc	0(4,%r3),0(%r3)			/* set tp->tv_sec to zero */
35	st	%r0,4(%r3)			/* store tp->tv_usec */
362:	lhi	%r2,0
37	br	%r14
383:	lhi	%r1,__NR_clock_getres		/* fallback to svc */
39	svc	0
40	br	%r14
41	CFI_ENDPROC
424:	.long	__CLOCK_REALTIME_RES
435:	.long	__CLOCK_COARSE_RES
44	.size	__kernel_clock_getres,.-__kernel_clock_getres
45