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=-9.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 4B080C433DB for ; Fri, 15 Jan 2021 15:16:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2200023888 for ; Fri, 15 Jan 2021 15:16:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733154AbhAOPQI (ORCPT ); Fri, 15 Jan 2021 10:16:08 -0500 Received: from mail-wm1-f43.google.com ([209.85.128.43]:38207 "EHLO mail-wm1-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730136AbhAOPQF (ORCPT ); Fri, 15 Jan 2021 10:16:05 -0500 Received: by mail-wm1-f43.google.com with SMTP id y187so7917960wmd.3; Fri, 15 Jan 2021 07:15:49 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=euDAszylF/ga+ziDscAVs0cSlmh+mJLUqDd+OrH+iq4=; b=iti7b1AtIxmQLGyges4XcHNyfGe6jCSyW4ku4yqYezqJO/tpZ0wD09RzV0cUSwchxJ AYrEFpV/MfZjqhcZnqrlQnCmVig6R+M+tfRXOB0AC6SD0Z5SAybtyualgdw/cWPCOX1g f68HYmRaS4hXuypXC+T+vKKV4/R9nHNP2LUltPcmBtFf7NwZ20UptoIZ/sZKdTkzagDO +jIuUgMMYwMbm+OpSle0Ag1a87f/y94j+hRDL8JHNCcfPkfbId0L6XxFwKajpqyTwjBE zepQpKiM6OJV7ysICSwg1mxTCb6W2IYxk55zTVFN0Ms/FIoQ6gcK8UssmR7UCZm4RStD XgpA== X-Gm-Message-State: AOAM533zr7oARGwnBp7TcxxK5svTKkk7S74Ac71hN65xZ1iuxQv1A8K0 Rn1u6vw3lcDukkr5kcvTC0E= X-Google-Smtp-Source: ABdhPJwqRU7rsnknKCUNz6a1Xv7V6y3ZTg7CJUZpCOk4twBGjvRFV4/51R4z7epuQoNSw1eZq+cm0g== X-Received: by 2002:a7b:c18d:: with SMTP id y13mr1369845wmi.22.1610723723238; Fri, 15 Jan 2021 07:15:23 -0800 (PST) Received: from kozik-lap (adsl-84-226-167-205.adslplus.ch. [84.226.167.205]) by smtp.googlemail.com with ESMTPSA id p15sm15309614wrt.15.2021.01.15.07.15.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Jan 2021 07:15:22 -0800 (PST) Date: Fri, 15 Jan 2021 16:15:20 +0100 From: Krzysztof Kozlowski To: Saravana Kannan Cc: Marek Szyprowski , Linux Samsung SOC , Bartlomiej Zolnierkiewicz , LKML , "Rafael J . Wysocki" Subject: Re: [PATCH] soc: samsung: pm_domains: Convert to regular platform driver Message-ID: <20210115151520.GA43049@kozik-lap> References: <20210113110320.13149-1-m.szyprowski@samsung.com> <58e1cfb2-cd35-badf-0238-7c62122e2d05@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 14, 2021 at 11:07:30AM -0800, Saravana Kannan wrote: > On Thu, Jan 14, 2021 at 11:03 AM Marek Szyprowski > wrote: > > > > Hi Saravana, > > > > On 13.01.2021 21:27, Saravana Kannan wrote: > > > On Wed, Jan 13, 2021 at 3:03 AM Marek Szyprowski > > > wrote: > > >> When Exynos power domain driver was introduced, the only way to ensure > > >> that power domains will be instantiated before the devices which belongs > > >> to them was to initialize them early enough, before the devices are > > >> instantiated in the system. This in turn required not to use any platform > > >> device infrastructure at all, as there have been no way to ensure proper > > >> probe order between devices. > > >> > > >> This has been finally changed and patch e590474768f1 ("driver core: Set > > >> fw_devlink=on by default") ensures that each device will be probbed only > > >> when its resource providers are ready. This allows to convert Exynos > > >> power domain driver to regular platform driver. > > >> > > >> This is also required by the mentioned commit to enable probing any > > >> device which belongs to the Exynos power domains, as otherwise the core > > >> won't notice that the power domains are in fact available. > > >> > > >> Signed-off-by: Marek Szyprowski > > >> --- > > >> Some more comments are in the following thread: > > >> https://protect2.fireeye.com/v1/url?k=8ac052ac-d55b6ba4-8ac1d9e3-0cc47a31c8b4-9068b559b0fd155d&q=1&e=b393c3ff-16ba-48a4-9d72-6805d02971d5&u=https%3A%2F%2Flore.kernel.org%2Flkml%2F2556a69b-5da5-bf80-e051-df2d02fbc40f%40samsung.com%2F > > >> --- > > >> ... > > > Skimmed through this patch and at a high level, it looks good for what > > > it's trying to do. Thanks for doing this! > > > > > > Btw, I assume that this won't work with fw_devlink=off/permissive > > > (default since 5.10 or earlier)? My concern is that we might > > > temporarily set fw_devlink=permissive by default if the other > > > breakages aren't fixed in time for 5.12? How do you want to handle that? > > > > I've applied my patch on top of vanilla v5.10 and checked on my test > > boards. Surprisingly everything works fine, so something must have been > > changed during the last few years as the power domain driver in the > > current form has been written long time ago. I remember that the moment > > when platform devices are created from the of nodes has been change at > > some point, so maybe this is somehow related. Anyway, the platform > > driver for Exynos power domains registered from core_initcall works fine > > with v5.10 kernel. > > > > I have no strong opinion on the way of merging this fix. It can go via > > Samsung tree, so in the end the v5.12-rc1 will have both my fix and your > > change, but won't be fully bisectable in-between. Krzysztof, what's your > > opinion? > > If it doesn't break anything without my changes, then let's try to get > it merged independent of my series. This is a good change even without > my changes. I agree, I'll take it via Samsung SoC. It's not the perfect solution - as Marek said, the tree won't be bisectable. Have in mind that some other boards/architectures might be broken where no one reported it yet, so fw_devlink=off/permissive might still be good choice for v5.12. Best regards, Krzysztof