hw/s390x/tod-qemu.c

   1 /*
   2  * TOD (Time Of Day) clock - QEMU implementation
   3  *
   4  * Copyright 2018 Red Hat, Inc.
   5  * Author(s): David Hildenbrand <david@redhat.com>
   6  *
   7  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   8  * See the COPYING file in the top-level directory.
   9  */
  10
  11 #include "qemu/osdep.h"
  12 #include "qapi/error.h"
  13 #include "hw/s390x/tod.h"
  14 #include "qemu/timer.h"
  15 #include "qemu/cutils.h"
  16 #include "cpu.h"
  17 #include "tcg_s390x.h"
  18
  19 static void qemu_s390_tod_get(const S390TODState *td, S390TOD *tod,
  20                               Error **errp)
  21 {
  22     *tod = td->base;
  23
  24     tod->low += time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
  25     if (tod->low < td->base.low) {
  26         tod->high++;
  27     }
  28 }
  29
  30 static void qemu_s390_tod_set(S390TODState *td, const S390TOD *tod,
  31                               Error **errp)
  32 {
  33     CPUState *cpu;
  34
  35     td->base = *tod;
  36
  37     td->base.low -= time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
  38     if (td->base.low > tod->low) {
  39         td->base.high--;
  40     }
  41
  42     /*
  43      * The TOD has been changed and we have to recalculate the CKC values
  44      * for all CPUs. We do this asynchronously, as "SET CLOCK should be
  45      * issued only while all other activity on all CPUs .. has been
  46      * suspended".
  47      */
  48     CPU_FOREACH(cpu) {
  49         async_run_on_cpu(cpu, tcg_s390_tod_updated, RUN_ON_CPU_NULL);
  50     }
  51 }
  52
  53 static void qemu_s390_tod_class_init(ObjectClass *oc, void *data)
  54 {
  55     S390TODClass *tdc = S390_TOD_CLASS(oc);
  56
  57     tdc->get = qemu_s390_tod_get;
  58     tdc->set = qemu_s390_tod_set;
  59 }
  60
  61 static void qemu_s390_tod_init(Object *obj)
  62 {
  63     S390TODState *td = S390_TOD(obj);
  64     struct tm tm;
  65
  66     qemu_get_timedate(&tm, 0);
  67     td->base.high = 0;
  68     td->base.low = TOD_UNIX_EPOCH + (time2tod(mktimegm(&tm)) * 1000000000ULL);
  69     if (td->base.low < TOD_UNIX_EPOCH) {
  70         td->base.high += 1;
  71     }
  72 }
  73
  74 static TypeInfo qemu_s390_tod_info = {
  75     .name = TYPE_QEMU_S390_TOD,
  76     .parent = TYPE_S390_TOD,
  77     .instance_size = sizeof(S390TODState),
  78     .instance_init = qemu_s390_tod_init,
  79     .class_init = qemu_s390_tod_class_init,
  80     .class_size = sizeof(S390TODClass),
  81 };
  82
  83 static void register_types(void)
  84 {
  85     type_register_static(&qemu_s390_tod_info);
  86 }
  87 type_init(register_types);