From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-gy0-f170.google.com (mail-gy0-f170.google.com [209.85.160.170]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 2C2B6B6F7B for ; Tue, 12 Jul 2011 05:59:56 +1000 (EST) Received: by gyb13 with SMTP id 13so2342280gyb.15 for ; Mon, 11 Jul 2011 12:59:53 -0700 (PDT) MIME-Version: 1.0 Sender: glikely@secretlab.ca In-Reply-To: <9F6FE96B71CF29479FF1CDC8046E150316F97F@039-SN1MPN1-003.039d.mgd.msft.net> References: <9F6FE96B71CF29479FF1CDC8046E150316EAB6@039-SN1MPN1-003.039d.mgd.msft.net> <9F6FE96B71CF29479FF1CDC8046E150316F97F@039-SN1MPN1-003.039d.mgd.msft.net> From: Grant Likely Date: Tue, 12 Jul 2011 04:59:33 +0900 Message-ID: Subject: Re: RFC: top level compatibles for virtual platforms To: Yoder Stuart-B08248 Content-Type: text/plain; charset=ISO-8859-1 Cc: Wood Scott-B07421 , Tabi Timur-B04825 , Alexander Graf , "linuxppc-dev@ozlabs.org" , Gala Kumar-B11780 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Jul 11, 2011 at 11:34 PM, Yoder Stuart-B08248 wrote: > > >> -----Original Message----- >> From: Tabi Timur-B04825 >> Sent: Friday, July 08, 2011 8:39 PM >> To: Yoder Stuart-B08248 >> Cc: Grant Likely; Benjamin Herrenschmidt; Gala Kumar-B11780; Wood Scott-= B07421; Alexander >> Graf; linuxppc-dev@ozlabs.org >> Subject: Re: RFC: top level compatibles for virtual platforms >> >> On Fri, Jul 8, 2011 at 1:43 PM, Yoder Stuart-B08248 wrote: >> >> > =A0 "MPC85xxDS" - for a virtual machine for the e500v2 type platforms >> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 and would support 85xx targets, plus P= 2020, P1022,etc >> > >> > =A0 "corenet-32-ds" - for a virtual machine similar to the 32-bit P408= 0 >> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 platforms >> > >> > =A0 "corenet-64-ds" - for a virtual machine based on a 64-bit corenet >> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 platform >> >> I think we should drop the "DS" because that's a name applied to certain= Freescale reference >> boards. >> >> Is being a CoreNet board really something meaningful with respect to KVM= ? =A0I don't see the >> connection. > > We're talking about what would be meaningful to Linux as a guest on > this platform here-- =A0Corenet-based SoCs are similar > in various ways, like using msgsnd for IPIs, having external proxy > support, etc. > > A corenet platform created by a QEMU/KVM looks similar > to other corenet SoCs. =A0 So, I'm trying to find some generic > compatible string that describes this platform. > >> Also, if these are KVM creations, shouldn't there be a "kvm" in the comp= atible string >> somewhere? > > There is nothing KVM specific about these platforms. =A0Any hypervisor > could create a similar virtual machine. > > A guest OS can determine specific info about the hypervisor it is > running on by looking at the /hypervisor node on the device > tree. > > We could put a generic -hv extension to indicate that this is > a virtual platform. > > =A0"mpc85xx-hv" > =A0"corenet-32-hv" > =A0"corenet-64-hv" However, compatible values are cheap and while theoretically any hypervisor could create a similar machine, the reality is probably subtle difference between the implementations. I'd rather see the compatible reflect the specific implementation. g.