blob: c7d791f32b98e4f8598684306f086c6193ff6e93 [file] [log] [blame]
Stefani Seiboldd2312e32014-03-17 23:22:01 +01001/*
2 * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
3 * Copyright 2003 Andi Kleen, SuSE Labs.
4 *
5 * Modified for x86 32 bit architecture by
6 * Stefani Seibold <stefani@seibold.net>
Stefani Seibold7c031562014-03-17 23:22:10 +01007 * sponsored by Rohde & Schwarz GmbH & Co. KG Munich/Germany
Stefani Seiboldd2312e32014-03-17 23:22:01 +01008 *
9 * Thanks to hpa@transmeta.com for some useful hint.
10 * Special thanks to Ingo Molnar for his early experience with
11 * a different vsyscall implementation for Linux/IA32 and for the name.
12 *
13 */
14
15#include <linux/timekeeper_internal.h>
16#include <asm/vgtod.h>
Stefani Seibold7c031562014-03-17 23:22:10 +010017#include <asm/vvar.h>
Stefani Seiboldd2312e32014-03-17 23:22:01 +010018
19DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data);
20
21void update_vsyscall_tz(void)
22{
Stefani Seibold7c031562014-03-17 23:22:10 +010023 vsyscall_gtod_data.tz_minuteswest = sys_tz.tz_minuteswest;
24 vsyscall_gtod_data.tz_dsttime = sys_tz.tz_dsttime;
Stefani Seiboldd2312e32014-03-17 23:22:01 +010025}
26
27void update_vsyscall(struct timekeeper *tk)
28{
29 struct vsyscall_gtod_data *vdata = &vsyscall_gtod_data;
30
Stefani Seibold7c031562014-03-17 23:22:10 +010031 gtod_write_begin(vdata);
Stefani Seiboldd2312e32014-03-17 23:22:01 +010032
33 /* copy vsyscall data */
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000034 vdata->vclock_mode = tk->tkr.clock->archdata.vclock_mode;
35 vdata->cycle_last = tk->tkr.cycle_last;
36 vdata->mask = tk->tkr.mask;
37 vdata->mult = tk->tkr.mult;
38 vdata->shift = tk->tkr.shift;
Stefani Seiboldd2312e32014-03-17 23:22:01 +010039
40 vdata->wall_time_sec = tk->xtime_sec;
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000041 vdata->wall_time_snsec = tk->tkr.xtime_nsec;
Stefani Seiboldd2312e32014-03-17 23:22:01 +010042
43 vdata->monotonic_time_sec = tk->xtime_sec
44 + tk->wall_to_monotonic.tv_sec;
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000045 vdata->monotonic_time_snsec = tk->tkr.xtime_nsec
Boris Ostrovsky28b92e02014-05-09 11:11:27 -040046 + ((u64)tk->wall_to_monotonic.tv_nsec
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000047 << tk->tkr.shift);
Stefani Seiboldd2312e32014-03-17 23:22:01 +010048 while (vdata->monotonic_time_snsec >=
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000049 (((u64)NSEC_PER_SEC) << tk->tkr.shift)) {
Stefani Seiboldd2312e32014-03-17 23:22:01 +010050 vdata->monotonic_time_snsec -=
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000051 ((u64)NSEC_PER_SEC) << tk->tkr.shift;
Stefani Seiboldd2312e32014-03-17 23:22:01 +010052 vdata->monotonic_time_sec++;
53 }
54
Stefani Seibold7c031562014-03-17 23:22:10 +010055 vdata->wall_time_coarse_sec = tk->xtime_sec;
Thomas Gleixnerd28ede82014-07-16 21:05:16 +000056 vdata->wall_time_coarse_nsec = (long)(tk->tkr.xtime_nsec >>
57 tk->tkr.shift);
Stefani Seiboldd2312e32014-03-17 23:22:01 +010058
Stefani Seibold7c031562014-03-17 23:22:10 +010059 vdata->monotonic_time_coarse_sec =
60 vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
61 vdata->monotonic_time_coarse_nsec =
62 vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
Stefani Seiboldd2312e32014-03-17 23:22:01 +010063
Stefani Seibold7c031562014-03-17 23:22:10 +010064 while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
65 vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
66 vdata->monotonic_time_coarse_sec++;
67 }
68
69 gtod_write_end(vdata);
Stefani Seiboldd2312e32014-03-17 23:22:01 +010070}