On 04.06.2018 14:05, Cornelia Huck wrote:
> On Fri, 25 May 2018 13:37:06 +0200
> David Hildenbrand <da...@redhat.com> wrote:
>
>> This allows a guest to change its TOD. We already take care of updating
>> all CKC timers from within S390TODClass.
>>
>> Use MO_ALIGN to load the operand manually - this will properly trigger a
>> SPECIFICATION exception.
>>
>> Signed-off-by: David Hildenbrand <da...@redhat.com>
>> ---
>> target/s390x/helper.h | 1 +
>> target/s390x/insn-data.def | 3 +--
>> target/s390x/misc_helper.c | 19 +++++++++++++++++++
>> target/s390x/translate.c | 9 +++++++++
>> 4 files changed, 30 insertions(+), 2 deletions(-)
>>
>
>> diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
>> index 2ef9de1cca..2f5cd6d22a 100644
>> --- a/target/s390x/misc_helper.c
>> +++ b/target/s390x/misc_helper.c
>> @@ -191,6 +191,25 @@ void tcg_s390_tod_updated(CPUState *cs, run_on_cpu_data
>> opaque)
>> helper_sckc(env, env->ckc);
>> }
>>
>> +/* Set Clock */
>> +uint32_t HELPER(sck)(CPUS390XState *env, uint64_t tod_low)
>> +{
>> + S390TODState *td = s390_get_tod();
>> + S390TODClass *tdc = S390_TOD_GET_CLASS(td);
>
> Would it make sense to cache the class as well?
Probably, but I don't think this is as critical as the flic (as this
code is TCG only and the class conversion should be fairly fast compared
to a device lookup).
>
>> + S390TOD tod = {
>> + .high = 0,
>> + .low = tod_low,
>> + };
>> + Error *err = NULL;
>> +
>> + qemu_mutex_lock_iothread();
>> + tdc->set(td, &tod, &err);
>> + qemu_mutex_unlock_iothread();
>> + g_assert(!err);
>> +
>> + return 0;
>> +}
>> +
>
--
Thanks,
David / dhildenb
