From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1165523AbdEYUJa (ORCPT <rfc822;w@1wt.eu>);
        Thu, 25 May 2017 16:09:30 -0400
Received: from mail-oi0-f68.google.com ([209.85.218.68]:36536 "EHLO
        mail-oi0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1162743AbdEYUJZ (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Thu, 25 May 2017 16:09:25 -0400
MIME-Version: 1.0
In-Reply-To: <8ddc7276-6296-2284-51d3-01093ccbeccb@oracle.com>
References: <CAMuHMdVjh+1TR19mUUQYHSazHnBHa4uxn7KyHUO+jAh7WDxy5Q@mail.gmail.com>
 <CAK8P3a1XZGQk3b3q+JFJ+mLgw_upUdAtTM1VBjHZq5f2m-YdUg@mail.gmail.com> <8ddc7276-6296-2284-51d3-01093ccbeccb@oracle.com>
From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 25 May 2017 22:09:24 +0200
X-Google-Sender-Auth: gOywdA_kzuhkxuYa4cQbCmjS6VQ
Message-ID: <CAK8P3a0MEkZ0wpsrit+sS8A0Z5T_jFWF5vFq_BqF2A1tReb7tQ@mail.gmail.com>
Subject: Re: CPU_BIG_ENDIAN in generic code (was: Re: [PATCH v3 3/7]
 arch/sparc: Define config parameter CPU_BIG_ENDIAN)
To: Babu Moger <babu.moger@oracle.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
        "David S. Miller" <davem@davemloft.net>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        sparclinux <sparclinux@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Linux-Arch <linux-arch@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-serial@vger.kernel.org" <linux-serial@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, May 25, 2017 at 4:51 PM, Babu Moger <babu.moger@oracle.com> wrote:
> On 5/24/2017 5:18 AM, Arnd Bergmann wrote:

>>> I guess the time is ripe for adding (both) symbols to all architectures?
>>
>> Good idea. I think we can do most of this by adding a few lines to
>> arch/Kconfig:
>>
>> config CPU_BIG_ENDIAN
>>          bool
>>
>> config CPU_LITTLE_ENDIAN
>>         def_bool !CPU_BIG_ENDIAN
>>
>> This way, we only need to add 'select CPU_BIG_ENDIAN' to the
>> architectures that are always big-endian, and we don't need to
>> change anything for the ones that have a single 'CPU_BIG_ENDIAN'
>> option.
>>
>> The three architectures that have a 'choice' statement (mips, ppc and
>> sh) will have to convert, and m32r will have to replace the
>
>
> what to you mean by "(mips, ppc andsh) will have to convert"?  Do you expect
> any changes here?
>

Kconfig does not allow you to have the same symbol as both a regular
'bool' and also 'bool within choice', so those three have to replace the
choice with a user-visible 'config CPU_BIG_ENDIAN' option like the
other ones have.

I also notice that  for arch/s390/Kconfig you now have both the
'select CPU_BIG_ENDIAN' and the 'config CPU_BIG_ENDIAN
def_bool y', I'd remove the second one in the same patch.

       Arnd