The new logic is compatible with old. So should not block to migrate from old QEMU. But new version cannot migrate to old.
Signed-off-by: Yang Zhang <yang.z.zh...@intel.com> --- hw/mc146818rtc.c | 43 ++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 40 insertions(+), 3 deletions(-) diff --git a/hw/mc146818rtc.c b/hw/mc146818rtc.c index 956f10b..3c31c0b 100644 --- a/hw/mc146818rtc.c +++ b/hw/mc146818rtc.c @@ -808,11 +808,48 @@ static int rtc_post_load(void *opaque, int version_id) return 0; } +static int rtc_load_old(QEMUFile *f, void *opaque, int version_id) +{ + RTCState *s = opaque; + uint8_t buf[77]; + + if (version_id > 2) { + return -EINVAL; + } + + qemu_get_buffer(f, s->cmos_data, sizeof(s->cmos_data)); + qemu_get_8s(f, &s->cmos_index); + + /* Skip loading of s->current_tm, we already have the + * information in cmos_data. + */ + qemu_get_buffer(f, buf, 7*4); + + qemu_get_timer(f, s->periodic_timer); + s->next_periodic_time = qemu_get_be64(f); + + /* Skip loading of next_second_time, second_timer, second_timer2. */ + qemu_get_buffer(f, buf, 3*8); + + rtc_set_time(s); + s->offset = 0; + s->old_guest_usec = 0; + check_update_timer(s); + + if (version_id >= 2) { + s->irq_coalesced = qemu_get_be32(f); + s->period = qemu_get_be32(f); + } + + return rtc_post_load(opaque, version_id); +} + static const VMStateDescription vmstate_rtc = { .name = "mc146818rtc", - .version_id = 2, - .minimum_version_id = 1, + .version_id = 3, + .minimum_version_id = 3, .minimum_version_id_old = 1, + .load_state_old = rtc_load_old, .post_load = rtc_post_load, .fields = (VMStateField []) { VMSTATE_BUFFER(cmos_data, RTCState), @@ -952,7 +989,7 @@ static int rtc_initfn(ISADevice *dev) memory_region_init_io(&s->io, &cmos_ops, s, "rtc", 2); isa_register_ioport(dev, &s->io, base); - qdev_set_legacy_instance_id(&dev->qdev, base, 2); + qdev_set_legacy_instance_id(&dev->qdev, base, 3); qemu_register_reset(rtc_reset, s); object_property_add(OBJECT(s), "date", "struct tm", -- 1.7.1