Note: I haven't tested this series yet. Thanks for finding the problem!
Il 17/05/2012 04:28, Zhang, Yang Z ha scritto:
> Use offset instead of timer to calculate guest rtc. Guest rtc is calculated
> by (base_rtc + guest_time_now - guest_time_last_update_rtc + offset).
> Base_rtc means the rtc value of last update.
> Guest_time_now means the guest time that access happens.
> Guest_time_last_update means the guest time of last update rtc.
> Offset is used when divider reset happened or set bit is changed.
>
> +static void rtc_set_offset(RTCState *s, bool running, bool div_reset)
> +{
> + if (div_reset)
> + s->offset = 500000;
> + else if (!running)
> + s->offset = s->old_guest_usec % USEC_PER_SEC;
> +}
This is probably clearer if you just inline it at the appropriate
places---especially because rtc_set_offset(s, 0, 0) is a no-op.
> -static void rtc_update_second(void *opaque)
> -{
> - RTCState *s = opaque;
> - int64_t delay;
> -
> - /* if the oscillator is not in normal operation, we do not update */
> - if ((s->cmos_data[RTC_REG_A] & 0x70) != 0x20) {
> - s->next_second_time += get_ticks_per_sec();
> - qemu_mod_timer(s->second_timer, s->next_second_time);
> - } else {
> - rtc_next_second(&s->current_tm);
> -
> - if (!(s->cmos_data[RTC_REG_B] & REG_B_SET)) {
> - /* update in progress bit */
> - s->cmos_data[RTC_REG_A] |= REG_A_UIP;
> - }
> - /* should be 244 us = 8 / 32768 seconds, but currently the
> - timers do not have the necessary resolution. */
> - delay = (get_ticks_per_sec() * 1) / 100;
> - if (delay < 1)
> - delay = 1;
> - qemu_mod_timer(s->second_timer2,
> - s->next_second_time + delay);
> - }
> -}
This patch breaks REG_A_UIP. You can squash patches 2 and 3 together to
avoid this problem.
Paolo
