From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fed1rmmtao04.cox.net (fed1rmmtao04.cox.net [68.230.241.35]) by ozlabs.org (Postfix) with ESMTP id 0E256679E9 for ; Thu, 5 May 2005 01:34:22 +1000 (EST) Date: Wed, 4 May 2005 08:34:19 -0700 From: Tom Rini To: Dan Malek Message-ID: <20050504153419.GV1221@smtp.west.cox.net> References: <17016.29775.224816.691409@cargo.ozlabs.ibm.com> <466e699745cf24e660e296530f6e34dc@embeddededge.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <466e699745cf24e660e296530f6e34dc@embeddededge.com> Cc: linuxppc-dev@ozlabs.org Subject: Re: [PATCH] Set cpu explicitly in kernel compiles List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, May 04, 2005 at 07:28:30AM -0400, Dan Malek wrote: > > On May 4, 2005, at 3:05 AM, Paul Mackerras wrote: > > >+cpu-opt-$(CONFIG_6xx) += -mcpu=750 -mtune=7450 > > What about cores that aren't CONFIG_6xx (8xx, 4xx, e500, etc.)? There's two choices. We can either go down the route x86 has of each CPU family choice defaulting to a cpu-opt-..., or we could do roughly what we do today and force the default cpu/tune to be whatever the default is on gcc-3.3.x (which I assume is really gcc-3.x.x, but..). Since there are folks working on optimizing toolchains on at least some of the newer CPUs, I'd be inclined to say we should do something like cpu-opt-y := ... gcc-3.3.x defaults ... cpu-opt-$(CONFIG_6xx) := -mcpu=750 -mtune=7450 cpu-opt-$(CONFIG_8xx) := -mcpu=800 -mtune=800 # Or whatever it is.. CFLAGS += $(cpu-opt-y) > How about we create a CONFIG_GCC_CPUOPT and > CONFIG_AS_OPT, and just get these out of the configuration file? Ick. It's possible, but unfun, to go from CONFIG_FOO="string" to cflags. -- Tom Rini http://gate.crashing.org/~trini/