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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 B7D2FC433E0 for ; Sun, 26 Jul 2020 16:06:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 939402073E for ; Sun, 26 Jul 2020 16:06:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="bPgAF82U" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727959AbgGZQGZ (ORCPT ); Sun, 26 Jul 2020 12:06:25 -0400 Received: from crapouillou.net ([89.234.176.41]:47986 "EHLO crapouillou.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726117AbgGZQGY (ORCPT ); Sun, 26 Jul 2020 12:06:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1595779582; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=d/PZVTcv9XrEDcYY/++e3Teye8k7bnbbZV/Cr5UVzy8=; b=bPgAF82UdLVnLdfUjsPgthYqEap5z1iDg/vjuXj6N456wugpclWOY0YZ3kzPZue4Tn1Ayk OStaiEu+djv0OyQZJr1RkXKj3UvE3XnStlDxd2UXiCAoVGLt22b2BSJUbdYOwxfJgq/EEO RXFikV31lzuZFk8CbOgd4cBd2fs2aK4= Date: Sun, 26 Jul 2020 18:06:13 +0200 From: Paul Cercueil Subject: Re: [PATCH v3 2/2] mtd: rawnand: ingenic: Limit MTD_NAND_JZ4780 to architecture only To: Arnd Bergmann Cc: Krzysztof Kozlowski , Harvey Hunt , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , linux-kernel@vger.kernel.org, linux-mtd Message-Id: In-Reply-To: References: <20200724145401.2566-1-krzk@kernel.org> <20200724145401.2566-3-krzk@kernel.org> <20200724155436.GA7460@kozik-lap> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le sam. 25 juil. 2020 =E0 20:30, Arnd Bergmann a =E9crit : > On Sat, Jul 25, 2020 at 2:17 PM Paul Cercueil =20 > wrote: >> Le ven. 24 juil. 2020 =E0 17:54, Krzysztof Kozlowski=20 >> a >> =E9crit : >> > On Fri, Jul 24, 2020 at 05:50:06PM +0200, Paul Cercueil wrote: >> >> Le ven. 24 juil. 2020 =E0 17:33, Krzysztof Kozlowski >> >> a =E9crit: >> >> > On Fri, 24 Jul 2020 at 17:19, Paul Cercueil=20 >> >> >> > wrote: >> >> >> >> On MIPS, the SoC selection is a Kconfig "choice", so you can=20 >> only >> >> support >> >> one SoC family, unfortunately. >> > >> > Let's say someone selected then some other architecture >> > (MIPS_ALCHEMY). >> > They could select this MTD driver. >> > >> > Does it mean they would be able to run it on Ingenic hardware? >>=20 >> In *theory* yes, as long as the Kconfig options that MACH_INGENIC >> selects are enabled, the kernel should boot and work on Ingenic=20 >> SoCs. >=20 > Right now, this won't work yet, because there are platform specific > functions that are implemented by each of the platforms in arch/mips, > e.g. arch/mips/generic/init.c and arch/mips/jz4740/setup.c. >=20 > A lot of the newer platforms are part of arch/mips/generic > (CONFIG_MIPS_GENERIC), which roughly corresponds to > CONFIG_ARCH_MULTIPLATFORM on in arch/arm/. > Similarly, there are header files in arch/mips/include/asm/mach-*/ > that conflict and you need to have the right one. >=20 > To have more than one platform enabled, each one needs to > have all of that platform code converted to fit into the > MIPS_GENERIC framework. This can be a lot of work, but > I suppose the ingenic platform would be a candidate for > which this makes sense, as long as new SoCs of that family > still come out. It should be much less work now that the vast majority of=20 arch/mips/jz4740 is gone. The code left is pretty much generic. I can=20 have a look to convert it to the MIPS_GENERIC framework. Although the code there is scary. Have a look at=20 arch/mips/include/asm/{machine,mips_machine}.h, you'll see what I mean. Anyway, I think we're way past the scope of this patch, so for this one: Acked-by: Paul Cercueil Cheers, -Paul