On 2022/5/19 下午11:24, Richard Henderson wrote:
On 5/19/22 06:04, yangxiaojuan wrote:
On 2022/5/19 上午3:59, Richard Henderson wrote:
On 5/17/22 04:30, Xiaojuan Yang wrote:
+static void ls7a_stop_toymatch(LS7ARtcState *s)
+{
+ int i;
+ uint64_t now;
+
+ now = qemu_clock_get_ms(rtc_clock);
+ for (i = 0; i < TIMER_NUMS; i++) {
+ if (s->toy_timer[i].flag) {
+ s->toy_timer[i].enable_offset =
s->toy_timer[i].timer->expire_time
+ - now;
+ timer_del(s->toy_timer[i].timer);
I don't think you need to check flag here, or update enable_offset.
Just an unconditional timer_del to stop the timer callback from firing.
Thanks very much, and i fixed it like this: Is this modification
appropriate?
static void ls7a_rtc_stop(LS7ARtcState *s)
{
int i;
int64_t rtc_val, rtc_diff, now;
now = ls7a_rtc_ticks();
for (i = 0; i < TIMER_NUMS; i++) {
if (s->rtc_timer[i].flag) {
rtc_val = s->rtcmatch[i];
rtc_diff = rtc_val - now - s->offset_rtc;
s->rtc_timer[i].save_offset = rtc_diff;
}
timer_del(s->rtc_timer[i].timer);
}
I think you should drop "flag" entirely. I don't see what it
accomplishes. It does not correspond to a bit in the state of the
La7a rtc device.
Do you know if the documentation is incomplete, and rtcmatch[n] == 0
is a magic number that indicates that the match value is disabled?
Because if there is no magic number for disabling the match, I would
expect *any* number, including 0, to match every 2**32 / 2**15 seconds
~= 36 hours.
The documentation is indeed not detailed, and we find a colleague in
hadware department to confirm your problem.
The rtc_write and rtc_match both are absolute value, rtc_write will add
counters if rtc_en enabled.
when rtc_write == rtc_match, rtc interrupt will happen. it also applies
to this situation: rtc_write=0, rtc_match=0, and the rtc_en enabled, irq
happens immediately. And the same for TOY.
It also occurs to me that EO is probably the thing that controls
whether RTC "ticks", and RTCEN is probably the thing that controls
whether RTC match interrupts are delivered, and the same for TOY. Can
you confirm this?
If RTC_EN disabled, it do not support to write rtc_write and
rtc_match[n], and the rtc_write will not add counters, and the interrupt
is also disabled, EO do not control this. So, we should check rtc_en
when write rtc_write and rtc_match. And the same for TOY.
Thanks.
Xiaojuan
