From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42448) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YDDpE-0008Vs-Kp for qemu-devel@nongnu.org; Mon, 19 Jan 2015 10:01:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YDDpB-00083H-G9 for qemu-devel@nongnu.org; Mon, 19 Jan 2015 10:01:08 -0500 Message-ID: <54BD1C2D.9070603@suse.de> Date: Mon, 19 Jan 2015 16:01:01 +0100 From: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= MIME-Version: 1.0 References: <1421667328-11800-1-git-send-email-mark.cave-ayland@ilande.co.uk> <1421667328-11800-3-git-send-email-mark.cave-ayland@ilande.co.uk> <54BCFC57.3010709@redhat.com> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 2/2] m48t59: add mem_base value to m48t59_init_isa() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Artyom Tarasenko Cc: Mark Cave-Ayland , qemu-devel , Alexander Graf , qemu-ppc@nongnu.org, Paolo Bonzini , =?UTF-8?B?SGVydsOpIFBvdXNzaW5lYXU=?= Am 19.01.2015 um 13:57 schrieb Artyom Tarasenko: > On Mon, Jan 19, 2015 at 1:45 PM, Paolo Bonzini wr= ote: >> On 19/01/2015 12:35, Mark Cave-Ayland wrote: >>> Similar to m48t59_init(), add a mem_base value so that NVRAM can be m= apped via >>> MMIO rather than ioport if required. >>> >>> Signed-off-by: Mark Cave-Ayland >>> --- >> >> Is it really ISA if it's MMIO? In other words, why can't this be a >> sysbus device? >=20 > On physical machines it's EBus, which is pretty much like 8-bit ISA. > So, I think modelling it as ISA is closer to to the reality. > But out of curiosity, would it be possible to have a sysbus device > somewhere in a middle of PCI space? [...] Why would you want to use a SysBusDevice in the first place? I previously discussed with Mark that it should be an EBusDevice, not an ISADevice or SysBusDevice. IndustryPack is an example of a custom bus that sits behind a PCI bridge and doesn't need a global variable. Also, wasn't Herv=C3=A9's(?) plan to get rid of mem_base completely by al= ways passing a pointer to ISADevice/ISABus around? It should only be needed when somewhere NULL is being passed, no? Regards, Andreas --=20 SUSE Linux GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg, Germany GF: Felix Imend=C3=B6rffer, Jane Smithard, Jennifer Guild, Dilip Upmanyu, Graham Norton; HRB 21284 (AG N=C3=BCrnberg)