From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eduard - Gabriel Munteanu Subject: Re: [Qemu-devel] Re: [RFC PATCH] AMD IOMMU emulation Date: Tue, 25 May 2010 14:23:51 +0300 Message-ID: <20100525112351.GA6234@localhost> References: <1274363407-24862-1-git-send-email-eduard.munteanu@linux360.ro> <20100524154030.GE1237@8bytes.org> <20100525083922.GF1237@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Blue Swirl , aliguori@us.ibm.com, avi@redhat.com, kvm@vger.kernel.org, qemu-devel@nongnu.org To: Joerg Roedel Return-path: Received: from fg-out-1718.google.com ([72.14.220.155]:47828 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756635Ab0EYLYY (ORCPT ); Tue, 25 May 2010 07:24:24 -0400 Received: by fg-out-1718.google.com with SMTP id e12so266735fga.1 for ; Tue, 25 May 2010 04:24:23 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20100525083922.GF1237@8bytes.org> Sender: kvm-owner@vger.kernel.org List-ID: On Tue, May 25, 2010 at 10:39:22AM +0200, Joerg Roedel wrote: > On Mon, May 24, 2010 at 08:10:16PM +0000, Blue Swirl wrote: > > On Mon, May 24, 2010 at 3:40 PM, Joerg Roedel wrote: > > >> + > > >> +#define MMIO_SIZE ? ? ? ? ? ? ? 0x2028 > > > > > > This size should be a power-of-two value. In this case probably 0x4000. > > > > Not really, the devices can reserve regions of any size. There were > > some implementation deficiencies in earlier versions of QEMU, where > > the whole page would be reserved anyway, but this limitation has been > > removed long time ago. > > The drivers for AMD IOMMU expect that to be 0x4000. At least the Linux > driver maps the MMIO region with this size. So the emulation should > reserve this amount of MMIO space too. > > Joerg Yeah, I'll change that, since I already reserve 0x4000 bytes in SeaBIOS for it (I did that to deal with the 16 KiB alignment requirement). Eduard