projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b020632e MS |
1 | /* |
| 2 | * Userland implementation of clock_gettime() 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_gettime | |
| 19 | .type __kernel_clock_gettime,@function | |
| 20 | __kernel_clock_gettime: | |
| 21 | .cfi_startproc | |
| 22 | basr %r5,0 | |
| 23 | 0: al %r5,21f-0b(%r5) /* get &_vdso_data */ | |
| b3423982 | 24 | chi %r2,__CLOCK_REALTIME |
| b020632e | 25 | je 10f |
| b3423982 | 26 | chi %r2,__CLOCK_MONOTONIC |
| b020632e MS |
27 | jne 19f |
| 28 | ||
| 29 | /* CLOCK_MONOTONIC */ | |
| 30 | ltr %r3,%r3 | |
| 31 | jz 9f /* tp == NULL */ | |
| 32 | 1: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ | |
| 33 | tml %r4,0x0001 /* pending update ? loop */ | |
| 34 | jnz 1b | |
| 35 | stck 24(%r15) /* Store TOD clock */ | |
| 36 | lm %r0,%r1,24(%r15) | |
| 37 | s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | |
| 38 | sl %r1,__VDSO_XTIME_STAMP+4(%r5) | |
| 39 | brc 3,2f | |
| 40 | ahi %r0,-1 | |
| 79c74ecb | 41 | 2: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */ |
| b020632e | 42 | lr %r2,%r0 |
| 79c74ecb | 43 | l %r0,__VDSO_TK_MULT(%r5) |
| b020632e MS |
44 | ltr %r1,%r1 |
| 45 | mr %r0,%r0 | |
| 46 | jnm 3f | |
| 79c74ecb | 47 | a %r0,__VDSO_TK_MULT(%r5) |
| b020632e | 48 | 3: alr %r0,%r2 |
| ca5de58b | 49 | al %r0,__VDSO_WTOM_NSEC(%r5) |
| b020632e MS |
50 | al %r1,__VDSO_WTOM_NSEC+4(%r5) |
| 51 | brc 12,5f | |
| 52 | ahi %r0,1 | |
| 79c74ecb MS |
53 | 5: l %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ |
| 54 | srdl %r0,0(%r2) /* >> tk->shift */ | |
| ca5de58b | 55 | l %r2,__VDSO_WTOM_SEC+4(%r5) |
| b020632e MS |
56 | cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ |
| 57 | jne 1b | |
| 58 | basr %r5,0 | |
| 59 | 6: ltr %r0,%r0 | |
| 60 | jnz 7f | |
| 61 | cl %r1,20f-6b(%r5) | |
| 62 | jl 8f | |
| 63 | 7: ahi %r2,1 | |
| 64 | sl %r1,20f-6b(%r5) | |
| 65 | brc 3,6b | |
| 66 | ahi %r0,-1 | |
| 67 | j 6b | |
| 68 | 8: st %r2,0(%r3) /* store tp->tv_sec */ | |
| 69 | st %r1,4(%r3) /* store tp->tv_nsec */ | |
| 70 | 9: lhi %r2,0 | |
| 71 | br %r14 | |
| 72 | ||
| 73 | /* CLOCK_REALTIME */ | |
| 74 | 10: ltr %r3,%r3 /* tp == NULL */ | |
| 75 | jz 18f | |
| 76 | 11: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ | |
| 77 | tml %r4,0x0001 /* pending update ? loop */ | |
| 78 | jnz 11b | |
| 79 | stck 24(%r15) /* Store TOD clock */ | |
| 80 | lm %r0,%r1,24(%r15) | |
| 81 | s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | |
| 82 | sl %r1,__VDSO_XTIME_STAMP+4(%r5) | |
| 83 | brc 3,12f | |
| 84 | ahi %r0,-1 | |
| 79c74ecb | 85 | 12: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */ |
| b020632e | 86 | lr %r2,%r0 |
| 79c74ecb | 87 | l %r0,__VDSO_TK_MULT(%r5) |
| b020632e MS |
88 | ltr %r1,%r1 |
| 89 | mr %r0,%r0 | |
| 90 | jnm 13f | |
| 79c74ecb | 91 | a %r0,__VDSO_TK_MULT(%r5) |
| b020632e | 92 | 13: alr %r0,%r2 |
| 79c74ecb | 93 | al %r0,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ |
| b020632e MS |
94 | al %r1,__VDSO_XTIME_NSEC+4(%r5) |
| 95 | brc 12,14f | |
| 96 | ahi %r0,1 | |
| 79c74ecb MS |
97 | 14: l %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ |
| 98 | srdl %r0,0(%r2) /* >> tk->shift */ | |
| 99 | l %r2,__VDSO_XTIME_SEC+4(%r5) | |
| b020632e MS |
100 | cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ |
| 101 | jne 11b | |
| 102 | basr %r5,0 | |
| 103 | 15: ltr %r0,%r0 | |
| 104 | jnz 16f | |
| 105 | cl %r1,20f-15b(%r5) | |
| 106 | jl 17f | |
| 107 | 16: ahi %r2,1 | |
| 108 | sl %r1,20f-15b(%r5) | |
| 109 | brc 3,15b | |
| 110 | ahi %r0,-1 | |
| 111 | j 15b | |
| 112 | 17: st %r2,0(%r3) /* store tp->tv_sec */ | |
| 113 | st %r1,4(%r3) /* store tp->tv_nsec */ | |
| 114 | 18: lhi %r2,0 | |
| 115 | br %r14 | |
| 116 | ||
| 117 | /* Fallback to system call */ | |
| 118 | 19: lhi %r1,__NR_clock_gettime | |
| 119 | svc 0 | |
| 120 | br %r14 | |
| 121 | ||
| 122 | 20: .long 1000000000 | |
| 123 | 21: .long _vdso_data - 0b | |
| 124 | .cfi_endproc | |
| 125 | .size __kernel_clock_gettime,.-__kernel_clock_gettime |