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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 07553C433E0 for ; Sun, 10 Jan 2021 17:36:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C45C8221FC for ; Sun, 10 Jan 2021 17:36:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726666AbhAJRgl (ORCPT ); Sun, 10 Jan 2021 12:36:41 -0500 Received: from outpost1.zedat.fu-berlin.de ([130.133.4.66]:60719 "EHLO outpost1.zedat.fu-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726267AbhAJRgl (ORCPT ); Sun, 10 Jan 2021 12:36:41 -0500 Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.94) with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1kyedC-000z7W-GH; Sun, 10 Jan 2021 18:35:58 +0100 Received: from p5b13a61e.dip0.t-ipconnect.de ([91.19.166.30] helo=[192.168.178.139]) by inpost2.zedat.fu-berlin.de (Exim 4.94) with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (envelope-from ) id 1kyedB-0007jE-HL; Sun, 10 Jan 2021 18:35:58 +0100 In-Reply-To: To: Arnd Bergmann Cc: Linux Kernel Mailing List , linux-m68k , Sparc kernel list , Linux-sh list From: John Paul Adrian Glaubitz Subject: Re: Old platforms: bring out your dead Message-ID: Date: Sun, 10 Jan 2021 18:35:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Original-Sender: glaubitz@physik.fu-berlin.de X-Originating-IP: 91.19.166.30 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Arnd! (Please let's have this cross-posted for more visibility. I only learned about this while reading Phoronix news) > I also looked at non-ARM platforms while preparing for my article. Some of > these look like they are no longer actively maintained or used, but I'm not > doing anything about those unless the maintainers would like me to: > > * h8300: Steven Rostedt has repeatedly asked about it to be removed > or fixed in 2020 with no reply. This was killed before in 2013, added back > in 2015 but has been mostly stale again since 2016 As far as I know, Yoshinori Sato is actively maintaining H8300 support, see: > https://osdn.net/projects/uclinux-h8/ > * c6x: Added in 2011, this has seen very few updates since, but > Mark still Acks patches when they come. Like most other DSP platforms, > the model of running Linux on a DSP appears to have been obsoleted > by using Linux on ARM with on-chip DSP cores running bare-metal code. > * sparc/sun4m: A patch for removing 32-bit Sun sparc support (not LEON) > is currently under review I don't think this has reached any agreement yet. Multiple people want it to stay. > * powerpc/cell: I'm the maintainer and I promised to send a patch to remove it. > it's in my backlog but I will get to it. This is separate from PS3, > which is actively > maintained and used; spufs will move to ps3 > * powerpc/chrp (32-bit rs6000, pegasos2): last updated in 2009 I'm still using this. Please keep it. > * powerpc/amigaone: last updated in 2009 > * powerpc/maple: last updated in 2011 > * m68k/{apollo,hp300,sun3,q40} these are all presumably dead and have not > seen updates in many years (atari/amiga/mac and coldfire are very much > alive) Dito. I have both sun3 and hp300 machines. > * mips/jazz: last updated in 2007 > * mips/cobalt: last updated in 2010 > > There might be some value in dropping old CPU support on architectures > and platforms that are almost exclusively used with more modern CPUs. > If there are only few users, those can still keep using v5.10 or v5.4 stable > kernels for a few more years. Again, I'm not doing anything about them, > except mention them since I did the research. > These are the oldest one by architecture, and they may have reached > their best-served-by-date: > > * 80486SX/DX: 80386 CPUs were dropped in 2012, and there are > indications that 486 have no users either on recent kernels. > There is still the Vortex86 family of SoCs, and the oldest of those were > 486SX-class, but all the modern ones are 586-class. > * Alpha 2106x: First generation that lacks some of the later features. > Since all Alphas are ancient by now, it's hard to tell whether these have > any fewer users. I don't see the point in crippling Alpha support. Does this achieve anything? > * IA64 Merced: first generation Itanium (2001) was quickly replaced by > Itanium II in 2002. > * MIPS R3000/TX39xx: 32-bit MIPS-II generation, mostly superseded by > 64-bit MIPS-III (R4000 and higher) starting in 1991. arch/mips still > supports these in DECstation and Toshiba Txx9, but it appears that most > of those machines are of the 64-bit kind. Later MIPS32 such as 4Kc and > later are rather different and widely used. > * PowerPC 601 (from 1992) just got removed, later 60x, 4xx, 8xx etc > are apparently all still used. > * SuperH SH-2: We discussed removing SH-2 (not J2 or SH-4) > support in the past, I don't think there were any objections, but > nobody submitted a patch. Isn't SH-2 basically J-2? I'm not sure what we would gain here. > * 68000/68328 (Dragonball): these are less capable than the > 68020+ or the Coldfire MCF5xxx line and similar to the 68360 > that was removed in 2016. Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaubitz@debian.org `. `' Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913