>> + td->base = *tod;
>> +
>> + td->base.low -= time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
>> + if (tod->low < td->base.low) {
>
> Just a matter of taste, but I'd rather use "td->base.low > tod->low"
> here instead (since the operations before and after the if-statement are
> related to td->base).
Changed.
>
>> + td->base.high--;
>> + }
>> +
>> + /*
>> + * The TOD has been changed and we have to recalculate the CKC values
>> + * for all CPUs. We do this asynchronously, as "SET CLOCK should be
>> + * issued only while all other activity on all CPUs .. has been
>> + * suspended".
>> + */
>> + CPU_FOREACH(cpu) {
>> + async_run_on_cpu(cpu, tcg_s390_tod_updated, RUN_ON_CPU_NULL);
>> + }
>> }
>>
>> static void qemu_s390_tod_class_init(ObjectClass *oc, void *data)
>> @@ -34,10 +58,24 @@ static void qemu_s390_tod_class_init(ObjectClass *oc,
>> void *data)
>> tdc->set = qemu_s390_tod_set;
>> }
>>
>> +static void qemu_s390_tod_init(Object *obj)
>> +{
>> + S390TODState *td = S390_TOD(obj);
>> + struct tm tm;
>> +
>> + qemu_get_timedate(&tm, 0);
>> + td->base.high = 0;
>> + td->base.low = TOD_UNIX_EPOCH + (time2tod(mktimegm(&tm)) *
>> 1000000000ULL);
>> + if (td->base.low < TOD_UNIX_EPOCH) {
>> + td->base.high += 1;
>> + }
>> +}
>
> Nit: It would be sufficient to do this in the realize() function instead.
Then I'll have to overwrite the realize function and store the
parent_realize function - something that I want to avoid if not really
necessary.
(for now it was also done in the cpu initfn, so that should be fine)
>
>> static TypeInfo qemu_s390_tod_info = {
>> .name = TYPE_QEMU_S390_TOD,
>> .parent = TYPE_S390_TOD,
>> .instance_size = sizeof(S390TODState),
>> + .instance_init = qemu_s390_tod_init,
>> .class_init = qemu_s390_tod_class_init,
>> .class_size = sizeof(S390TODClass),
>> };
> [...]
>> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
>> index dd5273949b..be341b5295 100644
>> --- a/target/s390x/misc_helper.c
>> +++ b/target/s390x/misc_helper.c
>> @@ -28,6 +28,8 @@
>> #include "qemu/timer.h"
>> #include "exec/exec-all.h"
>> #include "exec/cpu_ldst.h"
>> +#include "qapi/error.h"
>> +#include "tcg_s390x.h"
>>
>> #if !defined(CONFIG_USER_ONLY)
>> #include "sysemu/cpus.h"
>> @@ -39,6 +41,7 @@
>> #include "hw/s390x/ioinst.h"
>> #include "hw/s390x/s390-pci-inst.h"
>> #include "hw/boards.h"
>> +#include "hw/s390x/tod.h"
>> #endif
>>
>> /* #define DEBUG_HELPER */
>> @@ -138,25 +141,32 @@ void HELPER(spx)(CPUS390XState *env, uint64_t a1)
>> /* Store Clock */
>> uint64_t HELPER(stck)(CPUS390XState *env)
>> {
>> - uint64_t time;
>> + S390TODState *td = s390_get_todstate();
>> + S390TODClass *tdc = S390_TOD_GET_CLASS(td);
>> + S390TOD tod;
>>
>> - time = env->tod_offset +
>> - time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
>> -
>> - return time;
>> + tdc->get(td, &tod, &error_abort);
>> + return tod.low;
>> }
>>
>> /* Set Clock Comparator */
>> void HELPER(sckc)(CPUS390XState *env, uint64_t time)
>> {
>> + S390TODState *td = s390_get_todstate();
>> + S390TODClass *tdc = S390_TOD_GET_CLASS(td);
>> + S390TOD tod_base;
>> +
>> if (time == -1ULL) {
>> return;
>> }
>>
>> env->ckc = time;
>>
>> + tdc->get(td, &tod_base, &error_abort);
>> + tod_base.low -= time2tod(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
>
> So the tdc->get first adds the time2tod, and then you subtract it here
> again? Can't you simply use td->base.low directly instead?
That might be a good idea, previously I had tdc->get_base(), but dropped
it because it cannot be implemented for KVM.
Simply accessing the member here should be fine. Thanks!
>
>> /* difference between origins */
>> - time -= env->tod_offset;
>> + time -= tod_base.low;
>>
>> /* nanoseconds */
>> time = tod2time(time);
>> @@ -164,6 +174,14 @@ void HELPER(sckc)(CPUS390XState *env, uint64_t time)
>> timer_mod(env->tod_timer, time);
>> }
>
> ... I found only nits, so with or without my suggested modifications:
>
> Reviewed-by: Thomas Huth <th...@redhat.com>
>
--
Thanks,
David / dhildenb
