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=-7.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 6A253C74A42 for ; Thu, 11 Jul 2019 07:17:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C1BD21721 for ; Thu, 11 Jul 2019 07:17:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="ZJheqB/G" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728247AbfGKHRZ (ORCPT ); Thu, 11 Jul 2019 03:17:25 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:40694 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728104AbfGKHRY (ORCPT ); Thu, 11 Jul 2019 03:17:24 -0400 Received: from lelv0265.itg.ti.com ([10.180.67.224]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id x6B7H5iV123685; Thu, 11 Jul 2019 02:17:05 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1562829425; bh=0QBVygmwVoVpArXy+0GSkwrp5nxvHuYA5RBaCVFjx2Y=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=ZJheqB/GGT+3Qb6IaigPrlfbROfkgmpz01l7kwU4gZmw7jJOZNbtA8yr8+nnwLtSi snuq+QQne4StSqvEhrb5TC5ominD4zhoESey9fGqHpIix6BBFTFNvGJWzRXXOQWapx sWXh3BUqcDK2fAnpIF48sokoBPhMRvn7DtpmS+T4= Received: from DFLE104.ent.ti.com (dfle104.ent.ti.com [10.64.6.25]) by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x6B7H5HA015004 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 11 Jul 2019 02:17:05 -0500 Received: from DFLE111.ent.ti.com (10.64.6.32) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Thu, 11 Jul 2019 02:17:04 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE111.ent.ti.com (10.64.6.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Thu, 11 Jul 2019 02:17:04 -0500 Received: from [127.0.0.1] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id x6B7H2IB023513; Thu, 11 Jul 2019 02:17:02 -0500 Subject: Re: [PATCH v2] arm64: Kconfig.platforms: Enable GPIO_DAVINCI for ARCH_K3 To: Keerthy , Nishanth Menon CC: , , , , , References: <20190627110920.15099-1-j-keerthy@ti.com> <20190627143208.eeca4xyygml7s4n3@kahuna> <39f5e726-8542-b650-3bdb-7542e8fab8ac@ti.com> <20190628203752.rdb6vvc42qd5ofgd@kahuna> From: Tero Kristo Message-ID: <41475b80-4a9a-b594-7f66-5bf9b94c0bf0@ti.com> Date: Thu, 11 Jul 2019 10:16:59 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/07/2019 08:49, Keerthy wrote: > > > On 29/06/19 2:07 AM, Nishanth Menon wrote: >> On 09:08-20190628, Keerthy wrote: >> [..] >>>>> +    select GPIO_SYSFS >>>>> +    select GPIO_DAVINCI >>>> >>>> >>>> Could you help explain the logic of doing this? commit message is >>>> basically the diff in English. To me, this does NOT make sense. >>>> >>>> I understand GPIO_DAVINCI is the driver compatible, but we cant do >>>> this for >>>> every single SoC driver that is NOT absolutely mandatory for basic >>>> functionality. >>> >>> In case of ARM64 could you help me find the right place to enable >>> such SoC specific configs? >> >> Is'nt that what defconfig is supposed to be all about? >> >> arch/arm64/configs/defconfig >> >>> >>>> >>>> Also keep in mind the impact to arm64/configs/defconfig -> every single >>>> SoC in the arm64 world will be now rebuild with GPIO_SYSFS.. why force >>>> that? >>> >>> This was the practice in arm32 soc specific configs like >>> omap2plus_defconfig. GPIO_SYSFS was he only way to validate. Now i >>> totally >>> understand your concern about every single SoC rebuilding but now >>> where do >>> we need to enable the bare minimal GPIO_DAVINCI config? >> >> Well, SYSFS, I cannot agree testing as the rationale in >> Kconfig.platform. And, looking at [1], I see majority being mandatory >> components for the SoC bootup. However, most of the "optional" drivers >> go into arm64 as defconfig (preferably as a module?) and if you find a >> rationale for recommending DEBUG_GPIO, you could propose that to the >> community as well. >> >> Now, Thinking about this, I'd even challenge the current list of >> configs as >> being "select". I'd rather do an "imply"[2] - yes, you need this for the >> default dtb to boot, however a carefully carved dtb could boot with >> lesser driver set to get a smaller (and less functional) kernel. >> >>> >>> v1 i received feedback from Tero to enable in Kconfig.platforms. Hence i >>> shifted to this approach. >> >> I noticed that you were posting a v2, for future reference, please use >> diffstat section to point to lore/patchworks link to point at v1 (I >> did notice you mentioned you had an update, thanks - link will help >> catch up on older discussions). This helps a later revision reviewer >> like me to get context. >> >> Tero, would you be able to help with a better rationale as to where the >> boundaries are to be in your mind, rather than risk every single >> peripheral driver getting into ARCH_K3? > > Tero, > > Could you point me to a better place for enabling? > Well, thinking about what Nishanth said, we should probably keep the defconfig to bare minimal and only enable peripherals that are absolutely necessary for boot. We should eventually support eth / mmc-sd boot modes for K3 devices, but limit the configs to that. Rest we can carry within TI internal defconfigs, including this GPIO enabler. If GPIO becomes a must have for some future device / peripheral, we can re-consider this. -Tero > - Keerthy > >> >> As of right now, I'd rather we do not explode the current list out of >> bounds. NAK unless we can find a better rationale. >> >> >> [1] >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/Kconfig.platforms >> >> [2] https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt >> -- Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki