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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E2434D44D53 for ; Wed, 6 Nov 2024 11:39:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:Message-ID:References:In-Reply-To:Subject:Cc:To:From:Date: MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=X8FgUJIVPnDpXU0UCJKNG07n1qA7azNbt7tpYPJJ9xQ=; b=272UHYpYSIY+VR5ytKGWqbmNVu DoPkAtw9dXlOkmoUiRSTi+CHgEcx8ZOrapDxzC+zzK5Gya2MvevN1m2tazmCQpM/JI/nh5hW0jj8Z 45cBXSZNnSEJbwHbzrf8ydSr6PBDejwcTE4IPpGdlRD/sYm6GvJmRALaQmx9gxKCblaVq8jHclKtQ 6EjUMQnlABFNJMnbSTGgPmMtkXfO3DBFjGr74AlRX31pyvPOJe40gWqS7vFrPTLyqqliMij7D+onV Cb5YifvUJLN+t3jUcIRgRyRlfNdvtJJF7gNXSs91Aq2ke2HAqNWNeabbOyeUMeLiEjkmQZJl3Hirl uut3eeDQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t8eO1-00000002xBB-2tYz; Wed, 06 Nov 2024 11:39:45 +0000 Received: from mail.manjaro.org ([116.203.91.91]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t8dXA-00000002nCF-1zbe; Wed, 06 Nov 2024 10:45:10 +0000 MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=manjaro.org; s=2021; t=1730889906; h=from:from: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=X8FgUJIVPnDpXU0UCJKNG07n1qA7azNbt7tpYPJJ9xQ=; b=xsyXRFSjJuvIbSEjNJMRsLDbna6IqWYVKDqByUClVhHGywFD1sM/9Xjpu9MNIU80TEZukh 7HdK2aHO5PoYyj7SA04iVGh6LkXj2OK7QGdKwrJE31puGhujKR0ut9nCaJDQEqimpS1609 Qkhasy/4DzuL8PPbL3kUiZy23y6ZzmNlz61pTuYSYaF3G45ORvEvJ+aCquHi284ZpCN0d3 YQXZneHi7OP0ShfNFZfhCCuoYAMkz57Tl9eceq21x1HX4rduuCp6GVy2qHGBZZkmkb82xd FqhoUyAJFDTD2Wez0IsXX6uWOceKqSHbqV0m/sktblx46vPe/+4AGGBNKnh6qw== Date: Wed, 06 Nov 2024 11:45:06 +0100 From: Dragan Simic To: =?UTF-8?Q?Heiko_St=C3=BCbner?= Cc: linux-rockchip@lists.infradead.org, Quentin Schulz , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, alchark@gmail.com Subject: Re: [PATCH v2] arm64: dts: rockchip: Add OPP voltage ranges to RK3399 OP1 SoC dtsi In-Reply-To: <3252308.5fSG56mABF@diego> References: <3252308.5fSG56mABF@diego> Message-ID: <77bc2898bbbd2633d6713b4935bd5ee3@manjaro.org> X-Sender: dsimic@manjaro.org Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Authentication-Results: ORIGINATING; auth=pass smtp.auth=dsimic@manjaro.org smtp.mailfrom=dsimic@manjaro.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241106_024508_825932_5F8A294F X-CRM114-Status: GOOD ( 21.62 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello Heiko, On 2024-11-06 10:41, Heiko Stübner wrote: > Am Mittwoch, 6. November 2024, 10:32:06 CET schrieb Quentin Schulz: >> On 11/6/24 9:33 AM, Dragan Simic wrote: >> > Add support for voltage ranges to the CPU, GPU and DMC OPPs defined in the >> > SoC dtsi for Rockchip OP1, as a variant of the Rockchip RK3399. This may be >> > useful if there are any OP1-based boards whose associated voltage regulators >> > are unable to deliver the exact voltages; otherwise, it causes no functional >> > changes to the resulting OPP voltages at runtime. >> > >> > These changes cannot cause stability issues or any kind of damage, because >> > it's perfectly safe to use the highest voltage from an OPP group for each OPP >> > in the same group. The only possible negative effect of using higher voltages >> > is wasted energy in form of some additionally generated heat. >> > >> > Reported-by: Quentin Schulz >> >> Well, I merely highlighted that the voltage was different on OP1 >> compared to RK3399 for the 600MHz OPP :) >> >> So... If there's ONE SoC I'm pretty sure is working as expected it's >> the >> OP1 fitted on the Gru Chromebooks with the ChromiumOS kernel fork >> (though yes, I believe all Gru CB are EoL since August 2023). In the >> 6.1 >> kernel fork, there's also no range: >> https://chromium.googlesource.com/chromiumos/third_party/kernel/+/refs/heads/chromeos-6.1/arch/arm64/boot/dts/rockchip/rk3399-op1-opp.dtsi > > yeah, this somehow goes quite a bit into the "stuff that doesn't need > to > change" area. On the one hand it does make "some" sense to unify things > if we're using ranges everywhere else. I agree that it might be unneeded, but there's no possible harm, and unifying the things may be seen as beneficial. > On the other hand, as Quentin noted below, all existing OP1 devices > seem > to run just fine, and there won't be any more entering the kernel. Hmm, why can't we add more OP1-based devices? As I mentioned in my earlier response to Quentin, my plan is to implement the board dts for OP1-based TinkerBoard 2S, so I'd like to know is there something that might prevent that board dts from becoming merged? > So what do we realisitically gain here, except hiding existing > git-history > under another layer? Sorry, I'm not sure what would become hidden by this patch? >> So not sure we need to handle theoretical cases here. Will let >> maintainers decide on that one. FWIW, there are two other OP1 devices, >> the RockPi4A+ and RockPi4B+ which do not change the OPP either.