mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-13 00:36:48 +07:00
79c74ecbeb
Switch to the improved update_vsyscall interface that provides sub-nanosecond precision for gettimeofday and clock_gettime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
80 lines
2.0 KiB
ArmAsm
80 lines
2.0 KiB
ArmAsm
/*
|
|
* Userland implementation of gettimeofday() for 32 bits processes in a
|
|
* s390 kernel for use in the vDSO
|
|
*
|
|
* Copyright IBM Corp. 2008
|
|
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License (version 2 only)
|
|
* as published by the Free Software Foundation.
|
|
*/
|
|
#include <asm/vdso.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/unistd.h>
|
|
|
|
.text
|
|
.align 4
|
|
.globl __kernel_gettimeofday
|
|
.type __kernel_gettimeofday,@function
|
|
__kernel_gettimeofday:
|
|
.cfi_startproc
|
|
basr %r5,0
|
|
0: al %r5,13f-0b(%r5) /* get &_vdso_data */
|
|
1: ltr %r3,%r3 /* check if tz is NULL */
|
|
je 2f
|
|
mvc 0(8,%r3),__VDSO_TIMEZONE(%r5)
|
|
2: ltr %r2,%r2 /* check if tv is NULL */
|
|
je 10f
|
|
l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */
|
|
tml %r4,0x0001 /* pending update ? loop */
|
|
jnz 1b
|
|
stck 24(%r15) /* Store TOD clock */
|
|
lm %r0,%r1,24(%r15)
|
|
s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
|
|
sl %r1,__VDSO_XTIME_STAMP+4(%r5)
|
|
brc 3,3f
|
|
ahi %r0,-1
|
|
3: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */
|
|
st %r0,24(%r15)
|
|
l %r0,__VDSO_TK_MULT(%r5)
|
|
ltr %r1,%r1
|
|
mr %r0,%r0
|
|
jnm 4f
|
|
a %r0,__VDSO_TK_MULT(%r5)
|
|
4: al %r0,24(%r15)
|
|
al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */
|
|
al %r1,__VDSO_XTIME_NSEC+4(%r5)
|
|
brc 12,5f
|
|
ahi %r0,1
|
|
5: mvc 24(4,%r15),__VDSO_XTIME_SEC+4(%r5)
|
|
cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */
|
|
jne 1b
|
|
l %r4,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */
|
|
srdl %r0,0(%r4) /* >> tk->shift */
|
|
l %r4,24(%r15) /* get tv_sec from stack */
|
|
basr %r5,0
|
|
6: ltr %r0,%r0
|
|
jnz 7f
|
|
cl %r1,11f-6b(%r5)
|
|
jl 8f
|
|
7: ahi %r4,1
|
|
sl %r1,11f-6b(%r5)
|
|
brc 3,6b
|
|
ahi %r0,-1
|
|
j 6b
|
|
8: st %r4,0(%r2) /* store tv->tv_sec */
|
|
ltr %r1,%r1
|
|
m %r0,12f-6b(%r5)
|
|
jnm 9f
|
|
al %r0,12f-6b(%r5)
|
|
9: srl %r0,6
|
|
st %r0,4(%r2) /* store tv->tv_usec */
|
|
10: slr %r2,%r2
|
|
br %r14
|
|
11: .long 1000000000
|
|
12: .long 274877907
|
|
13: .long _vdso_data - 0b
|
|
.cfi_endproc
|
|
.size __kernel_gettimeofday,.-__kernel_gettimeofday
|