qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Mulyadi Santosa" <mulyadi.santosa@gmail.com>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] i8254 - Cannot change Timer frequency
Date: Sat, 11 Oct 2008 12:15:37 +0700	[thread overview]
Message-ID: <f284c33d0810102215w181fcd7dy61f206ad05fbc67@mail.gmail.com> (raw)
In-Reply-To: <1223657696.48ef88e0224fa@imp.free.fr>

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.

      reply	other threads:[~2008-10-11  5:15 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-10 16:54 [Qemu-devel] i8254 - Cannot change Timer frequency adrien lebre
2008-10-11  5:15 ` Mulyadi Santosa [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=f284c33d0810102215w181fcd7dy61f206ad05fbc67@mail.gmail.com \
    --to=mulyadi.santosa@gmail.com \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).