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 "qemu-common.h"
  13 #include "qapi/error.h"
  14 #include "hw/s390x/tod.h"
  15 #include "qemu/timer.h"
  16 #include "qemu/cutils.h"
  17 #include "qemu/module.h"
  18 #include "cpu.h"
  19 #include "tcg_s390x.h"
  20
  21 static void qemu_s390_tod_get(const S390TODState *td, S390TOD *tod,
  22                               Error **errp)
  23 {
  24     *tod = td->base;
  25
  26     tod->low += time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
  27     if (tod->low < td->base.low) {
  28         tod->high++;
  29     }
  30 }
  31
  32 static void qemu_s390_tod_set(S390TODState *td, const S390TOD *tod,
  33                               Error **errp)
  34 {
  35     CPUState *cpu;
  36
  37     td->base = *tod;
  38
  39     td->base.low -= time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
  40     if (td->base.low > tod->low) {
  41         td->base.high--;
  42     }
  43
  44     /*
  45      * The TOD has been changed and we have to recalculate the CKC values
  46      * for all CPUs. We do this asynchronously, as "SET CLOCK should be
  47      * issued only while all other activity on all CPUs .. has been
  48      * suspended".
  49      */
  50     CPU_FOREACH(cpu) {
  51         async_run_on_cpu(cpu, tcg_s390_tod_updated, RUN_ON_CPU_NULL);
  52     }
  53 }
  54
  55 static void qemu_s390_tod_class_init(ObjectClass *oc, void *data)
  56 {
  57     S390TODClass *tdc = S390_TOD_CLASS(oc);
  58
  59     tdc->get = qemu_s390_tod_get;
  60     tdc->set = qemu_s390_tod_set;
  61 }
  62
  63 static void qemu_s390_tod_init(Object *obj)
  64 {
  65     S390TODState *td = S390_TOD(obj);
  66     struct tm tm;
  67
  68     qemu_get_timedate(&tm, 0);
  69     td->base.high = 0;
  70     td->base.low = TOD_UNIX_EPOCH + (time2tod(mktimegm(&tm)) * 1000000000ULL);
  71     if (td->base.low < TOD_UNIX_EPOCH) {
  72         td->base.high += 1;
  73     }
  74 }
  75
  76 static TypeInfo qemu_s390_tod_info = {
  77     .name = TYPE_QEMU_S390_TOD,
  78     .parent = TYPE_S390_TOD,
  79     .instance_size = sizeof(S390TODState),
  80     .instance_init = qemu_s390_tod_init,
  81     .class_init = qemu_s390_tod_class_init,
  82     .class_size = sizeof(S390TODClass),
  83 };
  84
  85 static void register_types(void)
  86 {
  87     type_register_static(&qemu_s390_tod_info);
  88 }
  89 type_init(register_types);