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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 071BBC4741F for ; Tue, 29 Sep 2020 15:29:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A6D8520773 for ; Tue, 29 Sep 2020 15:29:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728860AbgI2P3X (ORCPT ); Tue, 29 Sep 2020 11:29:23 -0400 Received: from mout.kundenserver.de ([212.227.17.10]:35143 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725765AbgI2P3X (ORCPT ); Tue, 29 Sep 2020 11:29:23 -0400 Received: from mail-qt1-f179.google.com ([209.85.160.179]) by mrelayeu.kundenserver.de (mreue107 [212.227.15.145]) with ESMTPSA (Nemesis) id 1N4yNG-1kXHwj1vng-010vPY; Tue, 29 Sep 2020 17:29:21 +0200 Received: by mail-qt1-f179.google.com with SMTP id c18so3862140qtw.5; Tue, 29 Sep 2020 08:29:21 -0700 (PDT) X-Gm-Message-State: AOAM5317LkKvvxuzsi2MsXArNlWcblwQXLxwdFEBICLscrZIrvjBfQ8k ORzPu/VLCD3IhI0jGnOnP5JTCwJFSMHy/bpI3nk= X-Google-Smtp-Source: ABdhPJz9k/+3tANJB0rfgjiHIQ7nS0YJd5brzJANpAcdDDYLyyNmthovIwW6+viK77YcNpw2ms452kKZTl6zTF0jGxE= X-Received: by 2002:a37:5d8:: with SMTP id 207mr5108378qkf.352.1601393358920; Tue, 29 Sep 2020 08:29:18 -0700 (PDT) MIME-Version: 1.0 References: <20200715090400.4733-1-calvin.johnson@oss.nxp.com> <20200715090400.4733-2-calvin.johnson@oss.nxp.com> <20200929051703.GA10849@lsv03152.swis.in-blr01.nxp.com> <20200929134302.GF3950513@lunn.ch> <20200929143239.GI3950513@lunn.ch> In-Reply-To: From: Arnd Bergmann Date: Tue, 29 Sep 2020 17:29:02 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [net-next PATCH v7 1/6] Documentation: ACPI: DSD: Document MDIO PHY To: Andy Shevchenko Cc: Andrew Lunn , Calvin Johnson , Grant Likely , "Rafael J . Wysocki" , Jeremy Linton , Russell King - ARM Linux admin , Jon , Cristi Sovaiala , Ioana Ciornei , Florian Fainelli , Madalin Bucur , netdev , "linux.cj" , ACPI Devel Maling List , nd Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:mQmuimSRPfUjA+Y4ZwNetGU7p31zJt0xJ9vTV6xSsJCjn+JAcPP 7Y8uVwiI0XHNiQtPq1YZOV0Uk27X9/7/XRjf4MA7n3ZgSTLX8JUFDCWD+T6EHxAB6TUR6i8 qPrLNds94QQrri0gAo8WpATQfK7vEdSHRkd30hn8+lQ8YFSiGFSd+8/6f/PbcvXPBaws+56 +Jk8vK1m1UdNrZox1nLdA== X-UI-Out-Filterresults: notjunk:1;V03:K0:OzGHeofpsjY=:0Kk9t66pcqnJa7wGjNz5kl 3BDxOWcS+839O1WWIJOXAZe0ZpiGlFPu23CkTLgi/zNaNf56KXh0yugMS2JlFEWAYCwVHo1OV VBS5aF6A+jss26T9w2tUmuYP8NLBBZTjGRTVay/aKzGj3yALYnijlv6bD+s8aJY/COoZWniEl b4MVTga8zMp1pChC8arBF8xun9A0nvvP3tlzt3thXHrKgrOyI+P5hlgmLKomB+oDBEo4MtmCr m+gV0ZbXLdDIBGls5e+0h5jeQrjD8/RvjLVtowaNWUGimxihFIZ/I7MOolHuRm5eI3kNKqprl eR7I1sL6tX4Ga3KGrEXZN3+qdhga495rvfB+Rdw39ImW5eEFn9/GLZzBJ95HyEUhXlXSIsMf4 cYERMbKcUYgdEXdtmjLtof3pDqVJJHoxnN2HgPrJGsNb5Yjw/Ys25oCRNx09ZuNkQ+bBTYMKw kdZ24h+3W4EcIuQ2DwD4YtQCISrYE3+FcI9RVGf9DDGXi+zpFXRlkY3JxivIf0HE0PrcoEa9s qyVwJu3kSMdZRpKtGuDhXEpJhTpy5JVryBvNUVTNk4/ZV3gfNQX38TMrf53YbqLjiakSOIwAK 1ptdq/PhLpxQakw/mB++C0AvcsTS4OrE9eXEIJ98U+wMN9LrbDHAgDBhoDBHa0dsA/hF1andd 1dUqOZv0du/2bdRBCDOoN6N939f1i+IrjioGcE9V3xbsOHRcVlM5Big6Hq6xgtwl1Wyd68n/r +nAye1ynCXgrlMy4GpnOu1/X7hWO9xID7eJrdNoZQIEHAs9drngQ/33WpCMxKz0zd9TyjEeuP I31cxUw98oHZnzBMvNZSLGijQXjEvZEQTE06SKktcnYJv+O+EbIPBODvF6LkymDbYovc64CfY 9mSMrvDiXIJjcd3Y0w85MyEGWfsIT/dvYuHX8F/Ba1+3dG32tcVROBCQnu/OiElfT/DEElHfQ o7irRRFA22g5Lp5MrFg/vYBSIdOsNuww8YZ9o6TX2LR3tfdNCQgtT Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Sep 29, 2020 at 4:49 PM Andy Shevchenko wrote: > On Tue, Sep 29, 2020 at 5:32 PM Andrew Lunn wrote: > > On Tue, Sep 29, 2020 at 04:55:40PM +0300, Andy Shevchenko wrote: > > Does Tianocore, or any > > other implementations, have the needed le32_to_cpu() calls so that > > they can boot on a big endian CPU? > > Not of my knowledge. > > Is it feasible to boot an ARM system big endian? > > Not an ARM guy. Most CPUs these days support both big-endian and little-endian, and either allow code to switch between the two modes at runtime or are stateless in the way that you have two sets of load/store instructions, making endianness purely a compiler construct (see also: Intel's icc compiler has a big-endian mode using the MOVBE instruction). For Arm kernels, we assume that the firmware is little-endian, but you can build a big-endian kernel that switches into big-endian mode before doing anything else. As I said, I don't think that will ever be used with UEFI (and ACPI, by extension), since it would be a ton of work and few users care about big-endian kernels. Arnd