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 E46BCC77B76 for ; Thu, 20 Apr 2023 16:16:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233581AbjDTQQB (ORCPT ); Thu, 20 Apr 2023 12:16:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231341AbjDTQP6 (ORCPT ); Thu, 20 Apr 2023 12:15:58 -0400 Received: from ms.lwn.net (ms.lwn.net [IPv6:2600:3c01:e000:3a1::42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CD703596; Thu, 20 Apr 2023 09:15:57 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:281:8300:73::5f6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id 4038C2AE; Thu, 20 Apr 2023 16:15:57 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 ms.lwn.net 4038C2AE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lwn.net; s=20201203; t=1682007357; bh=dIoh7Uzva2QsUh5vyGcccNj94Y882Db73hATcucqawE=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=VANjqdpHV1W5XdXIB/wV+x8VC4ql3kGUs/Per8arX/UNuGOuxeKFb/7Av0anFrvms k2opc6Z1dgRJBQh0L+vo4aO3IZ6rk1D1BicOJephalElMdkwyzKggqcxWNqG4OVJLo KloTTSAaHOH4IGy3uYVMjyqnHdaIJTj7zO3MOaqMsisjTVETjJkOO66AcYdmNbZn3D xcJNJf0KQeN4YWpLFn2TkGN+FDvBF6CFmG6Ph9Y320FpFKBVDL1z2sFaliP6/C7v4y FTZSDSMqKbWjWmDM4+nEUU8ASgxHKz0/vH/CfYklDAAipUkksA5j/Ri8cMe226p3TD Mktp/fj4YA+LA== From: Jonathan Corbet To: Brian Masney , sboyd@kernel.org Cc: linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, mturquette@baylibre.com, linux-doc@vger.kernel.org Subject: Re: [PATCH] docs: clk: add documentation to log which clocks have been disabled In-Reply-To: <20230411192153.289688-1-bmasney@redhat.com> References: <20230411192153.289688-1-bmasney@redhat.com> Date: Thu, 20 Apr 2023 10:15:56 -0600 Message-ID: <87y1mmsf5v.fsf@meer.lwn.net> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Brian Masney writes: > The existing clk documentation has a section that talks about the > clk_ignore_unused kernel parameter. Add additional documentation that > describes how to log which clocks the kernel disables on bootup. This > will log messages like the following to the console on bootup: > > [ 1.268115] clk: Disabling unused clocks > [ 1.272167] clk_disable: gcc_usb_clkref_en > [ 1.276389] clk_disable: gcc_usb30_sec_sleep_clk > [ 1.281131] clk_disable: gcc_usb30_prim_sleep_clk > ... > > Signed-off-by: Brian Masney > --- > Documentation/driver-api/clk.rst | 5 +++++ > 1 file changed, 5 insertions(+) I've applied this, but... > diff --git a/Documentation/driver-api/clk.rst b/Documentation/driver-api/clk.rst > index 3cad45d14187..2199c0042e75 100644 > --- a/Documentation/driver-api/clk.rst > +++ b/Documentation/driver-api/clk.rst > @@ -258,6 +258,11 @@ clocks properly but rely on them being on from the bootloader, bypassing > the disabling means that the driver will remain functional while the issues > are sorted out. > > +You can see which clocks have been disabled by booting your kernel with these > +parameters: ...I took the liberty of making that "parameters::" so that the options would be formatted as a literal block. > + tp_printk trace_event=clk:clk_disable > + > To bypass this disabling, include "clk_ignore_unused" in the bootargs to the > kernel. Thanks, jon