From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:33352) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SPI7j-0004By-DR for qemu-devel@nongnu.org; Tue, 01 May 2012 14:48:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SPI7h-0003yH-Mm for qemu-devel@nongnu.org; Tue, 01 May 2012 14:48:30 -0400 Received: from p15195424.pureserver.info ([82.165.34.74]:59149) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SPI7h-0003y9-EW for qemu-devel@nongnu.org; Tue, 01 May 2012 14:48:29 -0400 Message-ID: <4FA0300B.7080001@ilande.co.uk> Date: Tue, 01 May 2012 19:48:43 +0100 From: Mark Cave-Ayland MIME-Version: 1.0 References: <4F9D797E.500@ilande.co.uk> <4F9D97F3.8080608@codemonkey.ws> <4F9E5028.7010306@redhat.com> <4F9E82C7.10706@ilande.co.uk> <4F9E9268.70408@redhat.com> <4F9E9906.8060401@ilande.co.uk> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Memory API: handling unassigned physical memory List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Blue Swirl Cc: qemu-devel@nongnu.org On 01/05/12 07:57, Blue Swirl wrote: >> Therefore I can't change it to my (modified) sbus_mmio_map() function >> because it would break other non-SPARC platforms, and AIUI there is nothing >> in the memory API that allows me to move a subregion to a different >> MemoryRegion parent, even if I can get a reference to it with >> sysbus_mmio_get_region() after the sysbus_mmio_map() call - or have I >> misunderstood something? > > Sysbus is used as a generic class for motherboard devices, there is an > assumption that there is no higher level bus. What we need here is a > full blown bus. The translations and mappigs between bus addresses and > motherboard addresses should be done in a Sysbus to SBus bridge > device, just like PCI host bridges do. Since SBus is mapped directly to physical addresses, is this mapping not just 1:1? Or does it make sense to re-work all the offsets of the various peripherals to be from the base address of the first slot? ATB, Mark.