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Date: Sat, 11 Oct 2008 12:15:37 +0700
From: "Mulyadi Santosa" <mulyadi.santosa@gmail.com>
Subject: Re: [Qemu-devel] i8254 - Cannot change Timer frequency
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To: qemu-devel@nongnu.org

Hi Adrien...

On Fri, Oct 10, 2008 at 11:54 PM, adrien lebre <lebre.adrien@free.fr> wrote:
> Re: i8254 - Cannot change Timer frequency
> by alebre on Wed Sep 17, 2008 4:37 pm
>
> What is the behavior of QEMU with regard to such instructions ?
> Does QEMU emulate the I8254 chip or does it simply forward the instruction to
> the host OS ? In that case, the host OS could simply does not consider such an
> instruction ?

I can not really answer about the i8524 emulation behaviour, but all I
know is that Qemu will turn it into setitimer() or RTC reprogramming
(via /dev/rtc). So the chance is, the granularity could be not as fine
as you expect. Especially if you end up using OS supplied timer, the
granularity will be 1/HZ.

Not an expert...just want to share my thoughts.

regards,

Mulyadi.