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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 71DC9C433F5 for ; Fri, 17 Sep 2021 07:29:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5653660F48 for ; Fri, 17 Sep 2021 07:29:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240307AbhIQHa1 (ORCPT ); Fri, 17 Sep 2021 03:30:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236843AbhIQHa0 (ORCPT ); Fri, 17 Sep 2021 03:30:26 -0400 Received: from mail-lf1-x136.google.com (mail-lf1-x136.google.com [IPv6:2a00:1450:4864:20::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92ABCC061574; Fri, 17 Sep 2021 00:29:04 -0700 (PDT) Received: by mail-lf1-x136.google.com with SMTP id y28so29176675lfb.0; Fri, 17 Sep 2021 00:29:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=tmHkW0s9+t/ONd+yDxBn//RRzbrXvdLqidVR1RkmYM0=; b=Y6iqwhp+URme2AkzCH6L9p/AD3OAkrXgDg2Hd/frLGzetlzUbIKV6+bnRjZGnvshpy /l8JJ277oOtCeGJJ+DIERy4c4FADZE2AqvdS92eFtq/8iEmpcFZinGXcBomIteSyN1Os H3zJHZMJpwnkl7B7C0uAOdR7Xs1mVHHWqQlFZ2m9sX4BgjcX3cXxbOXpD8sEky+cBYuQ eQfK/R7Xt5X8Pg5GjhjLBy5p8YD7AEDm12cjWqdvDAIYFnAudALwgNruuGmwu5zBUfSA vEukpaGJ7dGG4X8IEUpFe3U3uBvfYSpn9dWoQ0hv64jo7eyWAWFBU38H0V2URk/a0sfW ZLcQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tmHkW0s9+t/ONd+yDxBn//RRzbrXvdLqidVR1RkmYM0=; b=QQefVU8HDeVsPRKG/srJnRn1Vn+AINLWD6wLvwNd0s3W0SwKUW8ns10eg4V5/OuJ0E FVXUvRXuR0dvdntF3y6z7ryHa8XmthU1aOyBIzYJ771sq46xXRbPzs7sKb3+ajPK+2sZ PhPikh/pOQLew93AglQtsGq3cYd6UZ8BiMFphhCR1lSXQhYY09KydSz6xnbaHUGOh3aw QSnjPDzh2SNoZR3OD92Zka7O1ctb7oYMDv2AWeANIx4vR+v7iw6W5wbi3XDHqEgg3M6z btDw2BCNqruw7kkVYIuOcAMgTSIqjApY7gvHA8HHZQBXUnCe+5ixxovYfktNMl11dhUC lK9w== X-Gm-Message-State: AOAM533w+baypzddOkjoxUc5iQNSYKy+UJwPHk9Irr/sIM1FH0UHftTa xwgTXKlF6qMHCs0caC6Azb7zDi9A4BuFfPGYZps= X-Google-Smtp-Source: ABdhPJzGxQQwBhhrtEaweLkfzFUJA40jcPwllFvwIuOzWW6Oa+Fg+WH65jNMZ9ivUDYbeVPe3h9sKPNiDRJJGM8HZp4= X-Received: by 2002:a19:6512:: with SMTP id z18mr7266098lfb.106.1631863742007; Fri, 17 Sep 2021 00:29:02 -0700 (PDT) MIME-Version: 1.0 References: <20210915120325.20248-1-heiko.thiery@gmail.com> <7e7ee4244ababc0a46e0875222c7e37d@walle.cc> <898fd5e0-2073-3689-89b6-2c5071773786@kontron.de> In-Reply-To: <898fd5e0-2073-3689-89b6-2c5071773786@kontron.de> From: Heiko Thiery Date: Fri, 17 Sep 2021 09:28:51 +0200 Message-ID: Subject: Re: [PATCH] arm64: dts: imx8mm-kontron-n801x-som: do not allow to switch off buck2 To: Frieder Schrempf Cc: Michael Walle , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Krzysztof Kozlowski , Joakim Zhang , Shengjiu Wang , Rob Herring , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , =?UTF-8?Q?Guido_G=C3=BCnther?= , "Angus Ainslie (Purism)" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Frieder, Am Mi., 15. Sept. 2021 um 14:09 Uhr schrieb Frieder Schrempf : > > On 15.09.21 14:05, Michael Walle wrote: > > Am 2021-09-15 14:03, schrieb Heiko Thiery: > >> The buck2 output of the PMIC is the VDD core voltage of the cpu. > >> Switching off this will poweroff the CPU. Add the 'regulator-always-on' > >> property to avoid this. > > > > Mh, have this ever worked? Is there a commit which introduced a regression? > > Yes, this did work before, even without 'regulator-always-on'. I > currently don't understand why this is needed. The regulator is > referenced in the CPU nodes as 'cpu-supply'. This should be enough to > not disable it as long as the CPU is up. I rechecked that with 5.11, 5.10 and 5.9 and I see on all of them the same issue: [ 31.716031] vdd-5v: disabling [ 31.719032] rst-usb-eth2: disabling [ 31.722553] buck2: disabling While on that I tried to compare with other boards and see that they also have the cpu-voltage marked as "regulator-always-on". The only exception in dts/freescale is in imx8mq-librem5-devkit.dts [1] that has not set this property. I agree with you and don't understand why this is happening. Has anyone else an explanation? [1] https://elixir.bootlin.com/linux/latest/source/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts#L319 -- Heiko