From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38276) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YcWwm-0005Eq-Fy for qemu-devel@nongnu.org; Mon, 30 Mar 2015 06:29:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YcWwl-0004a9-HM for qemu-devel@nongnu.org; Mon, 30 Mar 2015 06:29:32 -0400 Message-ID: <5519256A.1010202@redhat.com> Date: Mon, 30 Mar 2015 12:28:58 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <5516FEDE.3030809@ilande.co.uk> <55191C97.8070308@redhat.com> <5519235C.6090004@ilande.co.uk> In-Reply-To: <5519235C.6090004@ilande.co.uk> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] ppc vga output breakage since commit c3c1bb99 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark Cave-Ayland , BALATON Zoltan , qemu-devel@nongnu.org Cc: Peter Crosthwaite , qemu-ppc@nongnu.org On 30/03/2015 12:20, Mark Cave-Ayland wrote: >> > >> > Of course, there's a QEMU regression too and I'm thinking of how to fix it. > Hmmm that's interesting because the documentation refers to both > registers being 16-bit: http://wiki.osdev.org/Bochs_VBE_Extensions. And > indeed the pseudo-code uses outpw/inpw for accesses, even though the > index and data registers are only 1 byte apart (0x1ce and 0x1cf) in I/O > space. Ugh, you're right. > Maybe OpenBIOS is getting the endian conversion incorrect for the word > access? (i.e. it's not converting to little endian). No, that's not it. It's basically treating the whole access as "unassigned" because 0x1cf is not allocated (on non-x86 machines, the DISPI data port is at 0x1d0). Paolo