| Martin Schwidefsky | b020632 | 2008-12-25 13:38:36 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * Userland implementation of gettimeofday() 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 | #include <asm/vdso.h> |
| 17 | #include <asm/asm-offsets.h> |
| 18 | #include <asm/unistd.h> |
| 19 | |
| 20 | .text |
| 21 | .align 4 |
| 22 | .globl __kernel_gettimeofday |
| 23 | .type __kernel_gettimeofday,@function |
| 24 | __kernel_gettimeofday: |
| 25 | .cfi_startproc |
| 26 | basr %r5,0 |
| 27 | 0: al %r5,13f-0b(%r5) /* get &_vdso_data */ |
| 28 | 1: ltr %r3,%r3 /* check if tz is NULL */ |
| 29 | je 2f |
| 30 | mvc 0(8,%r3),__VDSO_TIMEZONE(%r5) |
| 31 | 2: ltr %r2,%r2 /* check if tv is NULL */ |
| 32 | je 10f |
| 33 | l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ |
| 34 | tml %r4,0x0001 /* pending update ? loop */ |
| 35 | jnz 1b |
| 36 | stck 24(%r15) /* Store TOD clock */ |
| 37 | lm %r0,%r1,24(%r15) |
| 38 | s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ |
| 39 | sl %r1,__VDSO_XTIME_STAMP+4(%r5) |
| 40 | brc 3,3f |
| 41 | ahi %r0,-1 |
| 42 | 3: mhi %r0,1000 /* cyc2ns(clock,cycle_delta) */ |
| 43 | st %r0,24(%r15) |
| 44 | lhi %r0,1000 |
| 45 | ltr %r1,%r1 |
| 46 | mr %r0,%r0 |
| 47 | jnm 4f |
| 48 | ahi %r0,1000 |
| 49 | 4: al %r0,24(%r15) |
| 50 | srdl %r0,12 |
| 51 | al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */ |
| 52 | al %r1,__VDSO_XTIME_NSEC+4(%r5) |
| 53 | brc 12,5f |
| 54 | ahi %r0,1 |
| 55 | 5: mvc 24(4,%r15),__VDSO_XTIME_SEC+4(%r5) |
| 56 | cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ |
| 57 | jne 1b |
| 58 | l %r4,24(%r15) /* get tv_sec from stack */ |
| 59 | basr %r5,0 |
| 60 | 6: ltr %r0,%r0 |
| 61 | jnz 7f |
| 62 | cl %r1,11f-6b(%r5) |
| 63 | jl 8f |
| 64 | 7: ahi %r4,1 |
| 65 | sl %r1,11f-6b(%r5) |
| 66 | brc 3,6b |
| 67 | ahi %r0,-1 |
| 68 | j 6b |
| 69 | 8: st %r4,0(%r2) /* store tv->tv_sec */ |
| 70 | ltr %r1,%r1 |
| 71 | m %r0,12f-6b(%r5) |
| 72 | jnm 9f |
| 73 | al %r0,12f-6b(%r5) |
| 74 | 9: srl %r0,6 |
| 75 | st %r0,4(%r2) /* store tv->tv_usec */ |
| 76 | 10: slr %r2,%r2 |
| 77 | br %r14 |
| 78 | 11: .long 1000000000 |
| 79 | 12: .long 274877907 |
| 80 | 13: .long _vdso_data - 0b |
| 81 | .cfi_endproc |
| 82 | .size __kernel_gettimeofday,.-__kernel_gettimeofday |