From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e35.co.us.ibm.com (e35.co.us.ibm.com [32.97.110.153]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e35.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id B4BADB70E7 for ; Fri, 4 Feb 2011 10:16:04 +1100 (EST) Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by e35.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p13N20TC014906 for ; Thu, 3 Feb 2011 16:02:00 -0700 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p13NFxlH113820 for ; Thu, 3 Feb 2011 16:16:00 -0700 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p13NFxvx007034 for ; Thu, 3 Feb 2011 16:15:59 -0700 Subject: Re: [PATCH V2 4/6] powerpc/44x: don't use tlbivax on AMP systems From: Dave Kleikamp To: David Gibson In-Reply-To: <20110203050351.GK3032@yookeroo> References: <1296586126-32765-1-git-send-email-shaggy@linux.vnet.ibm.com> <1296586126-32765-5-git-send-email-shaggy@linux.vnet.ibm.com> <20110202230844.GG3032@yookeroo> <1296690839.12290.108.camel@shaggy-w500> <20110203050351.GK3032@yookeroo> Content-Type: text/plain; charset="ISO-8859-1" Date: Thu, 03 Feb 2011 17:15:57 -0600 Message-ID: <1296774957.14077.23.camel@shaggy-w500> Mime-Version: 1.0 Cc: linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2011-02-03 at 16:03 +1100, David Gibson wrote: > On Wed, Feb 02, 2011 at 05:53:59PM -0600, Dave Kleikamp wrote: > > On Thu, 2011-02-03 at 10:08 +1100, David Gibson wrote: > > > On Tue, Feb 01, 2011 at 12:48:44PM -0600, Dave Kleikamp wrote: > > > > Since other OS's may be running on the other cores don't use tlbivax > > > > > > [snip] > > > > +#ifdef CONFIG_44x > > > > +void __init early_init_mmu_44x(void) > > > > +{ > > > > + unsigned long root = of_get_flat_dt_root(); > > > > + if (of_flat_dt_is_compatible(root, "ibm,47x-AMP")) > > > > + amp = 1; > > > > +} > > > > +#endif /* CONFIG_44x */ > > > > > > A test against a hardcoded compatible string seems a nasty way to do > > > this. Maybe we should define a new boolean property for the root > > > node. > > > > I'm not crazy about this string, but I needed something in the device > > tree to key off of. Freescale has something similar (i.e. > > MPC8572DS-CAMP), so I chose to follow their example. I'd be happy to > > replace it with a boolean property. Any objection to just using > > "amp"? > > Bit too short, I think. I'd suggest either spelling out > 'asymmetric-multiprocessor' or 'cooperative-partition' (a more > accurate term, IMO). I could be wrong, but I thought the A stands for Asynchronous, not Asymmetric. I thought Asymmetric means that different types of tasks run on the secondary processors, as on the Cell. Anyway, going with 'cooperative-partition' would avoid that confusion. Shaggy -- Dave Kleikamp IBM Linux Technology Center