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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51773CCA473 for ; Wed, 15 Jun 2022 20:10:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344323AbiFOUKc (ORCPT ); Wed, 15 Jun 2022 16:10:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232127AbiFOUKb (ORCPT ); Wed, 15 Jun 2022 16:10:31 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AC98F366A0; Wed, 15 Jun 2022 13:10:30 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5E7A9B82177; Wed, 15 Jun 2022 20:10:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DFCC3C3411A; Wed, 15 Jun 2022 20:10:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655323828; bh=NYkoR6VqQygQruoVCGPg7fQxquBBe2DAIYM/jQYHsfg=; h=In-Reply-To:References:Subject:From:Cc:To:Date:From; b=W/jCa6hFgfFvdRNRccT5/vS5VEQsgQZqyRZyluBGuYIlkvQN8s+SYmffPB5zJNxd2 5z/eYzE3ApEu0a4c4cU2XZVOY5lYVdB/AGdEBZtKgM91id4n79jM4SyPixmhST+D5O n1K2RYaxl643MofSFRmMDJX7BMUWAowM/QH2BE/lgPh9xtalWNgZ7gQY1FaX8VOzaL 0buN4LH366T+t3Xo4JVAlo4fNTnnQCSZME2FD7M0dg1USyej5rH8KFxROkoy0BabCv ZV7y04beayolnJFe/10fiA3wkBYIu0A+rKGf6HW3pB/DyQGafZ7ei+asVyx3PACfi7 RwtObpuC+C7EQ== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable In-Reply-To: <20220517235919.200375-1-marex@denx.de> References: <20220517235919.200375-1-marex@denx.de> Subject: Re: [PATCH v3 1/2] dt-bindings: clk: Introduce 'critical-clocks' property From: Stephen Boyd Cc: Marek Vasut , Andrew Morton , Michael Turquette , Rob Herring , devicetree@vger.kernel.org To: Marek Vasut , linux-clk@vger.kernel.org Date: Wed, 15 Jun 2022 13:10:25 -0700 User-Agent: alot/0.10 Message-Id: <20220615201027.DFCC3C3411A@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Quoting Marek Vasut (2022-05-17 16:59:18) > diff --git a/Documentation/devicetree/bindings/clock/clock-bindings.txt b= /Documentation/devicetree/bindings/clock/clock-bindings.txt > index f2ea53832ac63..d7f7afe2cbd0c 100644 > --- a/Documentation/devicetree/bindings/clock/clock-bindings.txt > +++ b/Documentation/devicetree/bindings/clock/clock-bindings.txt > @@ -169,6 +169,22 @@ a shared clock is forbidden. > Configuration of common clocks, which affect multiple consumer devices c= an > be similarly specified in the clock provider node. > =20 > +=3D=3DCritical clocks=3D=3D > + > +Some platforms require some clocks to be always running, e.g. because th= ose > +clock supply devices which are not otherwise attached to the system. One > +example is a system where the SoC serves as a crystal oscillator replace= ment > +for a programmable logic device. The critical-clocks property of a clock > +controller allows listing clock which must never be turned off. > + > + clock-controller@a000f000 { > + compatible =3D "vendor,clk95; > + reg =3D <0xa000f000 0x1000> > + #clocks-cells =3D <1>; > + ... > + critical-clocks =3D , ; Historically "critical" is overloaded in the clk framework. We should avoid using that name. What does "critical" even mean? Instead I'd prefer "always-on-clocks" here, so we can indicate that these clks should always be on. It would also parallel the property in the regulator framework.