From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=43517 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PwLM2-0007qE-P1 for qemu-devel@nongnu.org; Sun, 06 Mar 2011 16:19:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PwLLL-000400-OZ for qemu-devel@nongnu.org; Sun, 06 Mar 2011 16:18:32 -0500 Received: from fmmailgate02.web.de ([217.72.192.227]:49673) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PwLLL-0003zT-9L for qemu-devel@nongnu.org; Sun, 06 Mar 2011 16:18:23 -0500 Message-ID: <4D73FA15.8090107@web.de> Date: Sun, 06 Mar 2011 22:18:13 +0100 From: Jan Kiszka MIME-Version: 1.0 References: <4D73B6CA.8070000@codemonkey.ws> <4D73C8CE.6080800@codemonkey.ws> <4D73CD43.1010004@web.de> <4D73F272.50105@codemonkey.ws> In-Reply-To: <4D73F272.50105@codemonkey.ws> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigEBDBA2ED609B1B494E3BEF74" 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) --------------enigEBDBA2ED609B1B494E3BEF74 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 2011-03-06 21:45, Anthony Liguori wrote: > On 03/06/2011 12:06 PM, Jan Kiszka wrote: >>> 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 o= f the >>> initialized of PIIX3 (for the PC at least). >>> >>> 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. >>> =20 >> There surely is some bus (or even multiple), just not external an one.= >> =20 >=20 > It almost doesn't matter. It would look like: >=20 > I8254 is-a DeviceState >=20 > SuperIO has-a I8254 >=20 > And the has-a relationship might be some custom bus mechanism (even if > it's purely a VHDL or software concept). >=20 > But in terms of modelling, we make I8254 a DeviceState because we don't= > care what bus it sits on. >=20 >> Most of the currently ISA-attached devices are chipset internal. >=20 > Yeah, and making them ISA devices was the wrong thing to do. This is > all going to have to be redone in the not too distant future. >=20 > An is-a relationship only makes sense when the device is naturally > represented as the parent object. >=20 >> 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 m= e. >> =20 >=20 > It's far from academic as this is user-visible and visible via the > command line. I thought it was stated before that there is no guarantee on the internal structure of our device tree as the user may explore it (as long as it's stable for the guest). Regarding command line: What are your worries here? The user can't mess with built-in devices. I still think we have more important things to improve than these cosmetic issues. Jan --------------enigEBDBA2ED609B1B494E3BEF74 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/ iEYEARECAAYFAk1z+hoACgkQitSsb3rl5xRi8gCbBIGVRK+NJJRc0xBnlrXw73Ta GD8An2CrfZMWgWi6CbRMN4fxZ0I4jo3K =QP2S -----END PGP SIGNATURE----- --------------enigEBDBA2ED609B1B494E3BEF74--