Tony Breeds | 74609f4 | 2007-06-26 09:50:32 +1000 | [diff] [blame] | 1 | /* |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 2 | * Userland implementation of gettimeofday() for 64 bits processes in a |
| 3 | * ppc64 kernel for use in the vDSO |
| 4 | * |
| 5 | * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), |
| 6 | * IBM Corp. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License |
| 10 | * as published by the Free Software Foundation; either version |
| 11 | * 2 of the License, or (at your option) any later version. |
| 12 | */ |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 13 | #include <asm/processor.h> |
| 14 | #include <asm/ppc_asm.h> |
| 15 | #include <asm/vdso.h> |
| 16 | #include <asm/asm-offsets.h> |
| 17 | #include <asm/unistd.h> |
| 18 | |
| 19 | .text |
| 20 | /* |
| 21 | * Exact prototype of gettimeofday |
| 22 | * |
| 23 | * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); |
| 24 | * |
| 25 | */ |
| 26 | V_FUNCTION_BEGIN(__kernel_gettimeofday) |
| 27 | .cfi_startproc |
| 28 | mflr r12 |
| 29 | .cfi_register lr,r12 |
| 30 | |
| 31 | mr r11,r3 /* r11 holds tv */ |
| 32 | mr r10,r4 /* r10 holds tz */ |
| 33 | bl V_LOCAL_FUNC(__get_datapage) /* get data page */ |
Will Schmidt | fde937d | 2007-06-29 15:49:50 -0500 | [diff] [blame] | 34 | cmpldi r11,0 /* check if tv is NULL */ |
Tony Breeds | 74609f4 | 2007-06-26 09:50:32 +1000 | [diff] [blame] | 35 | beq 2f |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 36 | lis r7,1000000@ha /* load up USEC_PER_SEC */ |
| 37 | addi r7,r7,1000000@l |
| 38 | bl V_LOCAL_FUNC(__do_get_tspec) /* get sec/us from tb & kernel */ |
| 39 | std r4,TVAL64_TV_SEC(r11) /* store sec in tv */ |
| 40 | std r5,TVAL64_TV_USEC(r11) /* store usec in tv */ |
Tony Breeds | 74609f4 | 2007-06-26 09:50:32 +1000 | [diff] [blame] | 41 | 2: cmpldi r10,0 /* check if tz is NULL */ |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 42 | beq 1f |
| 43 | lwz r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */ |
| 44 | lwz r5,CFG_TZ_DSTTIME(r3) |
| 45 | stw r4,TZONE_TZ_MINWEST(r10) |
| 46 | stw r5,TZONE_TZ_DSTTIME(r10) |
| 47 | 1: mtlr r12 |
Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 48 | crclr cr0*4+so |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 49 | li r3,0 /* always success */ |
| 50 | blr |
| 51 | .cfi_endproc |
| 52 | V_FUNCTION_END(__kernel_gettimeofday) |
| 53 | |
| 54 | |
| 55 | /* |
| 56 | * Exact prototype of clock_gettime() |
| 57 | * |
| 58 | * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); |
| 59 | * |
| 60 | */ |
| 61 | V_FUNCTION_BEGIN(__kernel_clock_gettime) |
| 62 | .cfi_startproc |
| 63 | /* Check for supported clock IDs */ |
| 64 | cmpwi cr0,r3,CLOCK_REALTIME |
| 65 | cmpwi cr1,r3,CLOCK_MONOTONIC |
Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 66 | cror cr0*4+eq,cr0*4+eq,cr1*4+eq |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 67 | bne cr0,99f |
| 68 | |
| 69 | mflr r12 /* r12 saves lr */ |
| 70 | .cfi_register lr,r12 |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 71 | mr r11,r4 /* r11 saves tp */ |
| 72 | bl V_LOCAL_FUNC(__get_datapage) /* get data page */ |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 73 | lis r7,NSEC_PER_SEC@h /* want nanoseconds */ |
| 74 | ori r7,r7,NSEC_PER_SEC@l |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 75 | 50: bl V_LOCAL_FUNC(__do_get_tspec) /* get time from tb & kernel */ |
| 76 | bne cr1,80f /* if not monotonic, all done */ |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 77 | |
| 78 | /* |
| 79 | * CLOCK_MONOTONIC |
| 80 | */ |
| 81 | |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 82 | /* now we must fixup using wall to monotonic. We need to snapshot |
| 83 | * that value and do the counter trick again. Fortunately, we still |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 84 | * have the counter value in r8 that was returned by __do_get_tspec. |
| 85 | * At this point, r4,r5 contain our sec/nsec values. |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 86 | */ |
| 87 | |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 88 | lwa r6,WTOM_CLOCK_SEC(r3) |
| 89 | lwa r9,WTOM_CLOCK_NSEC(r3) |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 90 | |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 91 | /* We now have our result in r6,r9. We create a fake dependency |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 92 | * on that result and re-check the counter |
| 93 | */ |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 94 | or r0,r6,r9 |
| 95 | xor r0,r0,r0 |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 96 | add r3,r3,r0 |
| 97 | ld r0,CFG_TB_UPDATE_COUNT(r3) |
| 98 | cmpld cr0,r0,r8 /* check if updated */ |
| 99 | bne- 50b |
| 100 | |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 101 | /* Add wall->monotonic offset and check for overflow or underflow. |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 102 | */ |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 103 | add r4,r4,r6 |
| 104 | add r5,r5,r9 |
| 105 | cmpd cr0,r5,r7 |
| 106 | cmpdi cr1,r5,0 |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 107 | blt 1f |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 108 | subf r5,r7,r5 |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 109 | addi r4,r4,1 |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 110 | 1: bge cr1,80f |
Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 111 | addi r4,r4,-1 |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 112 | add r5,r5,r7 |
| 113 | |
| 114 | 80: std r4,TSPC64_TV_SEC(r11) |
| 115 | std r5,TSPC64_TV_NSEC(r11) |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 116 | |
| 117 | mtlr r12 |
Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 118 | crclr cr0*4+so |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 119 | li r3,0 |
| 120 | blr |
| 121 | |
| 122 | /* |
| 123 | * syscall fallback |
| 124 | */ |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 125 | 99: |
| 126 | li r0,__NR_clock_gettime |
| 127 | sc |
| 128 | blr |
| 129 | .cfi_endproc |
| 130 | V_FUNCTION_END(__kernel_clock_gettime) |
| 131 | |
| 132 | |
| 133 | /* |
| 134 | * Exact prototype of clock_getres() |
| 135 | * |
| 136 | * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); |
| 137 | * |
| 138 | */ |
| 139 | V_FUNCTION_BEGIN(__kernel_clock_getres) |
| 140 | .cfi_startproc |
| 141 | /* Check for supported clock IDs */ |
| 142 | cmpwi cr0,r3,CLOCK_REALTIME |
| 143 | cmpwi cr1,r3,CLOCK_MONOTONIC |
Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 144 | cror cr0*4+eq,cr0*4+eq,cr1*4+eq |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 145 | bne cr0,99f |
| 146 | |
| 147 | li r3,0 |
Anton Blanchard | 5045ea3 | 2016-09-25 17:16:53 +1000 | [diff] [blame] | 148 | cmpldi cr0,r4,0 |
Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 149 | crclr cr0*4+so |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 150 | beqlr |
| 151 | lis r5,CLOCK_REALTIME_RES@h |
| 152 | ori r5,r5,CLOCK_REALTIME_RES@l |
| 153 | std r3,TSPC64_TV_SEC(r4) |
| 154 | std r5,TSPC64_TV_NSEC(r4) |
| 155 | blr |
| 156 | |
| 157 | /* |
| 158 | * syscall fallback |
| 159 | */ |
| 160 | 99: |
| 161 | li r0,__NR_clock_getres |
| 162 | sc |
| 163 | blr |
| 164 | .cfi_endproc |
| 165 | V_FUNCTION_END(__kernel_clock_getres) |
| 166 | |
Adhemerval Zanella | fcb41a2 | 2013-04-22 09:29:33 +0000 | [diff] [blame] | 167 | /* |
| 168 | * Exact prototype of time() |
| 169 | * |
| 170 | * time_t time(time *t); |
| 171 | * |
| 172 | */ |
| 173 | V_FUNCTION_BEGIN(__kernel_time) |
| 174 | .cfi_startproc |
| 175 | mflr r12 |
| 176 | .cfi_register lr,r12 |
| 177 | |
| 178 | mr r11,r3 /* r11 holds t */ |
| 179 | bl V_LOCAL_FUNC(__get_datapage) |
| 180 | |
| 181 | ld r4,STAMP_XTIME+TSPC64_TV_SEC(r3) |
| 182 | |
| 183 | cmpldi r11,0 /* check if t is NULL */ |
| 184 | beq 2f |
| 185 | std r4,0(r11) /* store result at *t */ |
| 186 | 2: mtlr r12 |
| 187 | crclr cr0*4+so |
| 188 | mr r3,r4 |
| 189 | blr |
| 190 | .cfi_endproc |
| 191 | V_FUNCTION_END(__kernel_time) |
| 192 | |
Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 193 | |
| 194 | /* |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 195 | * This is the core of clock_gettime() and gettimeofday(), |
| 196 | * it returns the current time in r4 (seconds) and r5. |
| 197 | * On entry, r7 gives the resolution of r5, either USEC_PER_SEC |
| 198 | * or NSEC_PER_SEC, giving r5 in microseconds or nanoseconds. |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 199 | * It expects the datapage ptr in r3 and doesn't clobber it. |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 200 | * It clobbers r0, r6 and r9. |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 201 | * On return, r8 contains the counter value that can be reused. |
| 202 | * This clobbers cr0 but not any other cr field. |
| 203 | */ |
| 204 | V_FUNCTION_BEGIN(__do_get_tspec) |
| 205 | .cfi_startproc |
| 206 | /* check for update count & load values */ |
| 207 | 1: ld r8,CFG_TB_UPDATE_COUNT(r3) |
| 208 | andi. r0,r8,1 /* pending update ? loop */ |
| 209 | bne- 1b |
| 210 | xor r0,r8,r8 /* create dependency */ |
| 211 | add r3,r3,r0 |
| 212 | |
| 213 | /* Get TB & offset it. We use the MFTB macro which will generate |
| 214 | * workaround code for Cell. |
| 215 | */ |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 216 | MFTB(r6) |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 217 | ld r9,CFG_TB_ORIG_STAMP(r3) |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 218 | subf r6,r9,r6 |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 219 | |
| 220 | /* Scale result */ |
| 221 | ld r5,CFG_TB_TO_XS(r3) |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 222 | sldi r6,r6,12 /* compute time since stamp_xtime */ |
| 223 | mulhdu r6,r6,r5 /* in units of 2^-32 seconds */ |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 224 | |
| 225 | /* Add stamp since epoch */ |
| 226 | ld r4,STAMP_XTIME+TSPC64_TV_SEC(r3) |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 227 | lwz r5,STAMP_SEC_FRAC(r3) |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 228 | or r0,r4,r5 |
| 229 | or r0,r0,r6 |
| 230 | xor r0,r0,r0 |
| 231 | add r3,r3,r0 |
| 232 | ld r0,CFG_TB_UPDATE_COUNT(r3) |
| 233 | cmpld r0,r8 /* check if updated */ |
| 234 | bne- 1b /* reload if so */ |
| 235 | |
| 236 | /* convert to seconds & nanoseconds and add to stamp */ |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 237 | add r6,r6,r5 /* add on fractional seconds of xtime */ |
| 238 | mulhwu r5,r6,r7 /* compute micro or nanoseconds and */ |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 239 | srdi r6,r6,32 /* seconds since stamp_xtime */ |
Paul Mackerras | 8fd63a9 | 2010-06-20 19:03:08 +0000 | [diff] [blame] | 240 | clrldi r5,r5,32 |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 241 | add r4,r4,r6 |
Paul Mackerras | 597bc5c | 2008-10-27 23:56:03 +0000 | [diff] [blame] | 242 | blr |
| 243 | .cfi_endproc |
| 244 | V_FUNCTION_END(__do_get_tspec) |