From patchwork Wed Feb 2 11:37:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Srba X-Patchwork-Id: 539652 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2BF31C433FE for ; Wed, 2 Feb 2022 11:40:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241872AbiBBLkk (ORCPT ); Wed, 2 Feb 2022 06:40:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233698AbiBBLkj (ORCPT ); Wed, 2 Feb 2022 06:40:39 -0500 Received: from mxd2.seznam.cz (mxd2.seznam.cz [IPv6:2a02:598:2::210]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21160C061714; Wed, 2 Feb 2022 03:40:38 -0800 (PST) Received: from email.seznam.cz by email-smtpc21a.ng.seznam.cz (email-smtpc21a.ng.seznam.cz [10.23.18.26]) id 5c6f5da1076109c85dc691ff; Wed, 02 Feb 2022 12:40:31 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=seznam.cz; s=beta; t=1643802031; bh=02935uyFlquI0a4iDdhDg5jx81ktMgh7hUVtFT1zXbw=; h=Received:From:To:Cc:Subject:Date:Message-Id:X-Mailer:In-Reply-To: References:MIME-Version:Content-Transfer-Encoding:X-szn-frgn: X-szn-frgc; b=DWzDVIrpD6b9nOplggA/JtU0A23MqTrYHVMaY63n4BgeRQ60riTuQkPvzEfUryXY5 b44ijX1qbhQ6RpKDPPbeEn14hy9e7DLJWPHe1Oce6KK3ZFxez1qt4TAC1wLkTZu2pA j9/4FZODB4/4JyN1mEs4u5sGFnIngZzBmN4IJkYo= Received: from localhost.localdomain (ip-111-27.static.ccinternet.cz [147.161.27.111]) by email-relay25.ng.seznam.cz (Seznam SMTPD 1.3.136) with ESMTP; Wed, 02 Feb 2022 12:39:52 +0100 (CET) From: michael.srba@seznam.cz To: Andy Gross , Bjorn Andersson , Rob Herring , Stephen Boyd , Philipp Zabel Cc: Linus Walleij , Florian Fainelli , Arnd Bergmann , Greg Kroah-Hartman , Saravana Kannan , linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org, Michael Srba , Michael Srba Subject: [PATCH v5 5/5] arm64: dts: qcom: msm8998: reserve potentially inaccessible clocks Date: Wed, 2 Feb 2022 12:37:22 +0100 Message-Id: <20220202113722.7550-5-michael.srba@seznam.cz> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220202113722.7550-1-michael.srba@seznam.cz> References: <20220202113722.7550-1-michael.srba@seznam.cz> MIME-Version: 1.0 X-szn-frgn: <9991ae1e-5145-46dc-b41e-c462e151b124> X-szn-frgc: <0> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org From: Michael Srba With the gcc driver now being more complete and describing clocks which might not always be write-accessible to the OS, conservatively specify all such clocks as protected in the SoC dts. The board dts - or even user-supplied dts - can override this property to reflect the actual configuration. Signed-off-by: Michael Srba --- CHANGES: - v2: add this patch - v3: fix missing Signed-off-by - v4: add a proper explanation as per review, (hopefully) fix the subject and commit message - v5: none --- arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi index f273bc1ff629..16dccf9d881e 100644 --- a/arch/arm64/boot/dts/qcom/msm8998.dtsi +++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi @@ -863,6 +863,21 @@ gcc: clock-controller@100000 { clock-names = "xo", "sleep_clk"; clocks = <&xo>, <&sleep_clk>; + + /* + * The hypervisor typically configures the memory region where these clocks + * reside as read-only for the HLOS. If the HLOS tried to enable or disable + * these clocks on a device with such configuration (e.g. because they are + * enabled but unused during boot-up), the device will most likely decide + * to reboot. + * In light of that, we are conservative here and we list all such clocks + * as protected. The board dts (or a user-supplied dts) can override the + * list of protected clocks if it differs from the norm, and it is in fact + * desired for the HLOS to manage these clocks + */ + protected-clocks = , + , + ; }; rpm_msg_ram: sram@778000 {