Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 24 May 2022 20:12:55 +0200
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Segher Boessenkool <segher@kernel.crashing.org>
Cc:     Michael Ellerman <mpe@ellerman.id.au>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc: e500: Fix compilation with gcc e500 compiler
Message-ID: <20220524181255.bmszzxmbwzv7zed7@pali>
References: <20220524093939.30927-1-pali@kernel.org>
 <20220524175955.GI25951@gate.crashing.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <20220524175955.GI25951@gate.crashing.org>
User-Agent: NeoMutt/20180716
Precedence: bulk

On Tuesday 24 May 2022 12:59:55 Segher Boessenkool wrote:
> Hi!
> 
> On Tue, May 24, 2022 at 11:39:39AM +0200, Pali Rohár wrote:
> > gcc e500 compiler does not support -mcpu=powerpc option. When it is
> > specified then gcc throws compile error:
> > 
> >   gcc: error: unrecognized argument in option ‘-mcpu=powerpc’
> >   gcc: note: valid arguments to ‘-mcpu=’ are: 8540 8548 native
> 
> What?  Are you using some modified version of GCC, perhaps?

Hello! I'm using official gcc version, no special modification.

> No version of GCC that isn't hamstrung can have this output.

gcc for e500 cores has really this output when you pass -mcpu=powerpc.

Upstream gcc dropped support for e500 cores during development of
version 9. But you can still compile and install gcc 8.5.0 (last version
of gcc 8) which has this full e500 support.

Really, you can easily try it. Debian 10 (Buster) has gcc 8.3.0 in its
default installation and also provides packages with cross compilers.
Just run 'sudo apt install gcc-powerpc-linux-gnuspe' on desktop amd64
version of Debian 10, it will install e500 cross compiler.

-mcpu=8540 specify e500v1 and -mcpu=8548 specify e500v2