Merge tag 's390-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
[linux-2.6-block.git] / arch / s390 / kernel / vdso64 / gettimeofday.S
CommitLineData
a17ae4c3 1/* SPDX-License-Identifier: GPL-2.0 */
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2/*
3 * Userland implementation of gettimeofday() for 64 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)
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8 */
9#include <asm/vdso.h>
10#include <asm/asm-offsets.h>
11#include <asm/unistd.h>
bc3703f2 12#include <asm/dwarf.h>
26f4414a 13#include <asm/ptrace.h>
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14
15 .text
16 .align 4
17 .globl __kernel_gettimeofday
18 .type __kernel_gettimeofday,@function
19__kernel_gettimeofday:
7bceec4e 20 CFI_STARTPROC
9b2efe03 21 aghi %r15,-16
7bceec4e 22 CFI_ADJUST_CFA_OFFSET 16
26f4414a 23 CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
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24 larl %r5,_vdso_data
250: ltgr %r3,%r3 /* check if tz is NULL */
26 je 1f
27 mvc 0(8,%r3),__VDSO_TIMEZONE(%r5)
281: ltgr %r2,%r2 /* check if tv is NULL */
29 je 4f
30 lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */
31 tmll %r4,0x0001 /* pending update ? loop */
32 jnz 0b
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33 stcke 0(%r15) /* Store TOD clock */
34 lg %r1,1(%r15)
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35 lg %r0,__VDSO_TS_END(%r5) /* TOD steering end time */
36 slgr %r0,%r1 /* now - ts_steering_end */
37 ltgr %r0,%r0 /* past end of steering ? */
38 jm 6f
39 srlg %r0,%r0,15 /* 1 per 2^16 */
40 tm __VDSO_TS_DIR+3(%r5),0x01 /* steering direction? */
41 jz 7f
42 lcgr %r0,%r0 /* negative TOD offset */
437: algr %r1,%r0 /* add steering offset */
446: sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
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45 msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */
46 alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */
47 lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */
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48 clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */
49 jne 0b
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50 lgf %r5,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */
51 srlg %r1,%r1,0(%r5) /* >> tk->shift */
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52 larl %r5,5f
532: clg %r1,0(%r5)
54 jl 3f
55 slg %r1,0(%r5)
56 aghi %r0,1
57 j 2b
583: stg %r0,0(%r2) /* store tv->tv_sec */
59 slgr %r0,%r0 /* tv_nsec -> tv_usec */
60 ml %r0,8(%r5)
61 srlg %r0,%r0,6
62 stg %r0,8(%r2) /* store tv->tv_usec */
634: lghi %r2,0
9b2efe03 64 aghi %r15,16
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65 CFI_ADJUST_CFA_OFFSET -16
66 CFI_RESTORE 15
b020632e 67 br %r14
7bceec4e 68 CFI_ENDPROC
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695: .quad 1000000000
70 .long 274877907
b020632e 71 .size __kernel_gettimeofday,.-__kernel_gettimeofday