Le 10/03/2021 à 13:32, BALATON Zoltan a écrit : > On Wed, 10 Mar 2021, Mark Cave-Ayland wrote: >> The 60Hz timer is initialised using timer_new_ns() meaning that the timer >> interval should be measured in ns, and therefore its period is a thousand >> times too short. >> >> Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk> >> --- >> hw/misc/mac_via.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/hw/misc/mac_via.c b/hw/misc/mac_via.c >> index f994fefa7c..c6e1552a59 100644 >> --- a/hw/misc/mac_via.c >> +++ b/hw/misc/mac_via.c >> @@ -302,8 +302,8 @@ static void via1_sixty_hz_update(MOS6522Q800VIA1State >> *v1s) >> MOS6522State *s = MOS6522(v1s); >> >> /* 60 Hz irq */ >> - v1s->next_sixty_hz = (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 16630) / >> - 16630 * 16630; >> + v1s->next_sixty_hz = (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 16630000) >> / >> + 16630000 * 16630000; > > Can you put this magic number in a #define maybe also rewriting it in a way > that shows it > corresponds to a 60 Hz interval. (There's NANOSECONDS_PER_SECOND defined in > include/qemu/timer.h > that could be used for that, there's also SCALE_MS that might replace 1000 * > 1000 elsewhere in this > file). Also NANOSECONDS_PER_SECOND / 60 is 16666666, should that value be > used here instead?
In fact, the Mac Frequency is not exactly 60 Hz, in docs we can find 60.147 Hz, in kernel 60.15 Hz. I Think there are several ways to compute it... Thanks, Laurent
