From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [RFC PATCH 1/3] add generic hypercall support Date: Wed, 6 May 2009 18:52:15 +0200 Message-ID: <200905061852.15931.arnd@arndb.de> References: <20090505132005.19891.78436.stgit@dev.haskins.net> <4A019614.9080702@codemonkey.ws> <4A01A9C5.5010601@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Cc: Anthony Liguori , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, avi@redhat.com To: Gregory Haskins Return-path: Received: from moutng.kundenserver.de ([212.227.126.177]:53607 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751733AbZEFQwW (ORCPT ); Wed, 6 May 2009 12:52:22 -0400 In-Reply-To: <4A01A9C5.5010601@novell.com> Content-Disposition: inline Sender: kvm-owner@vger.kernel.org List-ID: On Wednesday 06 May 2009, Gregory Haskins wrote: > Ok, so we would > need to come up with these pio_calls for x86, and no other arch can use > the infrastructure (but wait, PPC can use PCI too, so how does that > work? It must be either MMIO emulation or its not supported? That puts > us back to square one). PowerPC already has an abstraction for PIO and MMIO because certain broken hardware chips don't do what they should, see arch/powerpc/platforms/cell/io-workarounds.c for the only current user. If you need to, you could do the same on x86 (or generalize the code), but please don't add another level of indirection on top of this. Arnd <><