1/*
 2 * Userland implementation of clock_getres() for 32 bits processes in a
 3 * s390 kernel for use in the vDSO
 4 *
 5 *  Copyright IBM Corp. 2008
 6 *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 7 *
 8 * This program is free software; you can redistribute it and/or modify
 9 * it under the terms of the GNU General Public License (version 2 only)
10 * as published by the Free Software Foundation.
11 */
12#include <asm/vdso.h>
13#include <asm/asm-offsets.h>
14#include <asm/unistd.h>
15
16	.text
17	.align 4
18	.globl __kernel_clock_getres
19	.type  __kernel_clock_getres,@function
20__kernel_clock_getres:
21	.cfi_startproc
22	chi	%r2,__CLOCK_REALTIME
23	je	0f
24	chi	%r2,__CLOCK_MONOTONIC
25	jne	3f
260:	ltr	%r3,%r3
27	jz	2f				/* res == NULL */
28	basr	%r1,0
291:	l	%r0,4f-1b(%r1)
30	xc	0(4,%r3),0(%r3)			/* set tp->tv_sec to zero */
31	st	%r0,4(%r3)			/* store tp->tv_usec */
322:	lhi	%r2,0
33	br	%r14
343:	lhi	%r1,__NR_clock_getres		/* fallback to svc */
35	svc	0
36	br	%r14
374:	.long	__CLOCK_REALTIME_RES
38	.cfi_endproc
39	.size	__kernel_clock_getres,.-__kernel_clock_getres