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 22DB7C433FE for ; Mon, 28 Feb 2022 16:01:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237740AbiB1QCc (ORCPT ); Mon, 28 Feb 2022 11:02:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235403AbiB1QCb (ORCPT ); Mon, 28 Feb 2022 11:02:31 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E847D83038; Mon, 28 Feb 2022 08:01:52 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AC646ED1; Mon, 28 Feb 2022 08:01:52 -0800 (PST) Received: from [10.57.39.47] (unknown [10.57.39.47]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B79223F70D; Mon, 28 Feb 2022 08:01:50 -0800 (PST) Message-ID: <25913b62-7d55-1118-34dd-f7662adef019@arm.com> Date: Mon, 28 Feb 2022 16:01:45 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH 1/3] dt-bindings: spi: Update clocks property for ARM pl022 Content-Language: en-GB To: Mark Brown Cc: Kuldeep Singh , linux-arm-kernel@lists.infradead.org, linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Linus Walleij References: <20220228124345.99474-1-singh.kuldeep87k@gmail.com> <20220228124345.99474-2-singh.kuldeep87k@gmail.com> <6e14bdd4-5924-dd58-41ef-5bdb5561913b@arm.com> <1763f668-2582-c05e-7ac8-d635bc84ef82@arm.com> From: Robin Murphy In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 2022-02-28 15:46, Mark Brown wrote: > On Mon, Feb 28, 2022 at 03:27:08PM +0000, Robin Murphy wrote: >> On 2022-02-28 15:11, Mark Brown wrote: > >>> Well, it could also be that the clock is wired to some other clock which >>> is always on (which I guess is why the driver allows this in the first >>> place, there's a lot of sloppy code around stuff like that in the tree). > >> I wouldn't say the driver "allows" it, so much as it just blindly grabs the >> first clock assuming it's SSPCLK per the binding, and thus it will happen to >> work out if the underlying physical clock is the same as, or equivalent to, >> the APB PCLK. Otherwise, it's already into some degree of not working >> properly, by virtue of reading the wrong clock rate. > > Ah, the APB clock requirement is inherited from the AMBA implementation > isn't it? We really ought to be extending an AMBA binding here... Yup, both the "apb_pclk" clock specifier and the "arm,primecell" compatible technically belong to the common AMBA binding, but I'm not sure whether schema has the ability to compose at such fine-grained a level :/ Robin.