From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: [Qemu-devel] KVM call minutes 2013-01-29 - Port I/O
Date: Wed, 30 Jan 2013 16:45:40 +0100
Message-ID: <51094024.20803@redhat.com>
References: <871ud4gfoa.fsf@elfo.elfo> <5109065B.4060803@suse.de>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-15
Content-Transfer-Encoding: 7bit
Cc: Juan Quintela <quintela@redhat.com>,
	KVM devel mailing list <kvm@vger.kernel.org>,
	qemu-devel <qemu-devel@nongnu.org>,
	Alexander Graf <agraf@suse.de>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	qemu-ppc <qemu-ppc@nongnu.org>,
	=?ISO-8859-15?Q?Herv=E9_Poussineau?= <hpoussin@reactos.org>,
	David Gibson <david@gibson.dropbear.id.au>,
	Alon Levy <alevy@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Anthony Liguori <anthony@codemonkey.ws>
To: =?ISO-8859-15?Q?Andreas_F=E4rber?= <afaerber@suse.de>
Return-path: <kvm-owner@vger.kernel.org>
Received: from mx1.redhat.com ([209.132.183.28]:26629 "EHLO mx1.redhat.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1753439Ab3A3PrF (ORCPT <rfc822;kvm@vger.kernel.org>);
	Wed, 30 Jan 2013 10:47:05 -0500
In-Reply-To: <5109065B.4060803@suse.de>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

  Hi,

> hw/qxl.c:    portio_list_add(qxl_vga_port_list,
> pci_address_space_io(dev), 0x3b0);
> hw/vga.c:        portio_list_add(vga_port_list, address_space_io, 0x3b0);

That reminds me I should solve this in a more elegant way.

qxl takes over the vga io ports.  The reason it does this is because qxl
switches into vga mode in case the vga ports are accessed while not in
vga mode.  After doing the check (and possibly switching mode) the vga
handler is called to actually handle it.

That twist makes it a bit hard to convert vga ...

Anyone knows how one would do that with the memory api instead? I think
taking over the ports is easy as the memory regions have priorities so I
can simply register a region with higher priority. I have no clue how to
forward the access to the vga code though.

Anyone has clues / suggestions?

thanks,
  Gerd