From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=52868 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PwIMF-0008Qw-57 for qemu-devel@nongnu.org; Sun, 06 Mar 2011 13:07:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PwIME-0004Mn-2F for qemu-devel@nongnu.org; Sun, 06 Mar 2011 13:07:07 -0500 Received: from fmmailgate01.web.de ([217.72.192.221]:55457) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PwIMD-0004Mg-Gy for qemu-devel@nongnu.org; Sun, 06 Mar 2011 13:07:06 -0500 Message-ID: <4D73CD43.1010004@web.de> Date: Sun, 06 Mar 2011 19:06:59 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <4D73B6CA.8070000@codemonkey.ws> <4D73C8CE.6080800@codemonkey.ws> In-Reply-To: <4D73C8CE.6080800@codemonkey.ws> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig7EB8B9CD094D6ADD283AC563" Sender: jan.kiszka@web.de Subject: [Qemu-devel] Re: [PATCH 4/4] i8254: convert to qdev List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Blue Swirl , qemu-devel This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig7EB8B9CD094D6ADD283AC563 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 2011-03-06 18:47, Anthony Liguori wrote: > On 03/06/2011 10:47 AM, Blue Swirl wrote: >>> The PIT is not an ISA device. Modelling it as such is worse than >>> leaving it >>> unmodelled. >>> =20 >> No. These days, PIT is part of Super I/O chip, which is accessed via >> LPC bus. LPC is from software point of view equal to ISA. Therefore, >> in absence of LPC, ISA is correct. >> =20 >=20 > In the system we model, the PIT is part of the PIIX3. The right way to= > model it is as a DeviceState that's no_user=3D1 and created as part of = the > initialized of PIIX3 (for the PC at least). >=20 > LPC is still an expansion bus and it's primarily used for discrete > components like a TPM. For components that are all part of a Super I/O= > chip, there really just isn't a bus in the middle. There surely is some bus (or even multiple), just not external an one. Most of the currently ISA-attached devices are chipset internal. They belong to the PIIX3, so they need to be attached to some bus that is owned by this device. If that is its ISA bus or a separate one for internal devices - really, this looks like an academic discussion to me. Jan --------------enig7EB8B9CD094D6ADD283AC563 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org/ iEYEARECAAYFAk1zzUcACgkQitSsb3rl5xQBGgCdHjTVyS5h+RvuTGcl+rFJLbRB j94AoMeacu/XK7AHp877L40nNZA1MgT2 =C2HR -----END PGP SIGNATURE----- --------------enig7EB8B9CD094D6ADD283AC563--