From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D0E3BC6FA82 for ; Fri, 23 Sep 2022 12:24:49 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4MYrv35MLbz3dqm for ; Fri, 23 Sep 2022 22:24:47 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lists.ozlabs.org (Postfix) with ESMTP id 4MYrtc6Gx0z2yHT for ; Fri, 23 Sep 2022 22:24:24 +1000 (AEST) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 28NCMM4p016809; Fri, 23 Sep 2022 07:22:22 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 28NCMMFW016808; Fri, 23 Sep 2022 07:22:22 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Fri, 23 Sep 2022 07:22:21 -0500 From: Segher Boessenkool To: Nicholas Piggin Subject: Re: [PATCH 1/2] powerpc/64s: Fix GENERIC_CPU build flags for PPC970 / G5 Message-ID: <20220923122221.GM25951@gate.crashing.org> References: <20220921014103.587954-1-npiggin@gmail.com> <20220921185031.GE25951@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Sep 23, 2022 at 05:17:45PM +1000, Nicholas Piggin wrote: > On Thu Sep 22, 2022 at 4:50 AM AEST, Segher Boessenkool wrote: > > On Wed, Sep 21, 2022 at 11:41:02AM +1000, Nicholas Piggin wrote: > > > Big-endian GENERIC_CPU supports 970, but builds with -mcpu=power5. > > > POWER5 is ISA v2.02 whereas 970 is v2.01 plus Altivec. 2.02 added > > > the popcntb instruction which a compiler might use. > > > > > > Use -mcpu=power4. > > > > > > Fixes: 471d7ff8b51b ("powerpc/64s: Remove POWER4 support") > > > Signed-off-by: Nicholas Piggin > > > > Reviewed-by: Segher Boessenkool > > > > Thank you! > > > > Maybe superfluous, but some more context: GCC's -mcpu=power4 means > > POWER4+, ISA 2.01, according to our documentation. There is no > > difference with ISA 2.00 (what plain POWER4 implements) for anything > > GCC does. > > Huh, okay. Well I guess we are past that point now, interesting that > another ISA version was done for 4+ though, and then another for 5. > I don't see a list of changes from 2.00 in the public version, I > wonder what else changed other than mtmsrd. I think searching for "POWER4+" will give you everything. I cannot find a public 2.00 either, yeah. I listed everything I think changed elsewhere in the thread. Segher