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,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 31BD5C433E0 for ; Mon, 11 Jan 2021 09:51:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D721522AAF for ; Mon, 11 Jan 2021 09:51:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728575AbhAKJvB (ORCPT ); Mon, 11 Jan 2021 04:51:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:39428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728256AbhAKJvA (ORCPT ); Mon, 11 Jan 2021 04:51:00 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6649D22527; Mon, 11 Jan 2021 09:50:11 +0000 (UTC) Subject: Re: Old platforms: bring out your dead To: Geert Uytterhoeven , John Paul Adrian Glaubitz Cc: Daniel Palmer , Linux ARM , Linux Kernel Mailing List , Krzysztof Adamski , Oleksij Rempel , Baruch Siach , Russell King - ARM Linux , Daniel Tang , =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= , Jamie Iles , Barry Song , Viresh Kumar , Linus Walleij , Jonas Jensen , Marc Gonzalez , Hartley Sweeten , Lubomir Rintel , Neil Armstrong , Shawn Guo , Alex Elder , Alexander Shiyan , Koen Vandeputte , Hans Ulli Kroll , Vladimir Zapolskiy , Wei Xu , Steven Rostedt , Yoshinori Sato , Mark Salter , Michael Ellerman , Geert Uytterhoeven , Thomas Bogendoerfer , linux-m68k References: <803a40ba-d0cb-e5e2-9d57-f1b70d7aee37@physik.fu-berlin.de> From: Greg Ungerer Message-ID: <9e9cc4ad-38b0-f799-cd0e-c1e1c7e3501c@linux-m68k.org> Date: Mon, 11 Jan 2021 19:50:07 +1000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/1/21 7:36 pm, Geert Uytterhoeven wrote: > Hi Adrian, > > On Mon, Jan 11, 2021 at 10:26 AM John Paul Adrian Glaubitz > wrote: >> On 1/11/21 10:20 AM, Geert Uytterhoeven wrote: >>>> Sounds interesting. Do these SoCs come with an MMU? And do they use the >>>> ColdFire instruction set or do they run plain 68k code? >>> >>> No MMU, plain m68k code. >>> >>> 68328 Soc = 68000 core + some peripherals, >>> 68360 SoC = CPU32 core (based on 68020 + some peripherals. >> >> OK, I guess that would be useful for the NoMMU Linux port. > > Note that 68360 support was removed from the kernel in 2016, as > Arnd said. And that 68360 was bit rotten for a very long time before that. Nobody ever seemed to show much interest in it. Keep in mind that the 68328 family of parts are pretty slow too... >>> Anyone working on integrating m68k (and SPARC and MIPS?) softcores in >>> LiteX? ;-) >> >> I'm personally waiting for the Vampire to gain support for the real 68851 >> as the hardware in general looks very attractive [1]. > > The 68851 is way too complex for what's needed (who needs support for > 256 byte pages (https://lwn.net/Articles/839746/)?). > They'd be better off implementing something simpler, like 68040 MMU > support, or perhaps even a software-controlled TLB like most RISC > architectures (incl. ColdFire?). The latter would require more changes > to Linux, though. Yep, the ColdFire MMU is a software controlled TLB. Regards Greg