From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E14F17DFF2; Wed, 6 Nov 2024 14:13:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730902424; cv=none; b=TIqzY+xGal8edyA+yzKe3oL0Ou9lbH5Qlf+aekPVfHY7532eqoYYMAwbmMXr2nI1Sv3jNyaJDL/er2jTTGVkgFlp3AH6X1JPrGdvufEmaKepX93dQaJVhgFxM6kCa7Zd3HUK67gdk7XhBUQgvcwbvT2PML2ivNWKiCOdIHMM+Nk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730902424; c=relaxed/simple; bh=+pLThVS1L/IAbP/3NgRHcs2F5PUAiuFpNCtGhSyvvF8=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=RBPOYgUWOxERDV3E9+rmZtsCOocgFfyd26Ns8OBaWW1xlS0kqTN9C51KzpPaSkXtMAdOMaJGV1GLuddQ4Vl9fse5jlFvb/s+JCtS5gLphQ1nuKO4ORmtq3wS+zxqAyQLLM64teArALvumb246FeMltRdZJFrUI1dmpWCeMKCQCA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vRA45zPB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vRA45zPB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 535A7C4CEC6; Wed, 6 Nov 2024 14:13:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730902423; bh=+pLThVS1L/IAbP/3NgRHcs2F5PUAiuFpNCtGhSyvvF8=; h=Date:Subject:From:To:Cc:References:In-Reply-To:From; b=vRA45zPBaLdOc77fWsdIuvUEiqfe3+G8GIwHpl0Uek4hP1DTnRDRwMeU8IoVhjPnU DZB41e+XVNvEvRgEVJ4xgEEyIPLoZ6ZKKyH57Q5mJe8Yu/q3KzInppbwZUSzCXlSM7 XRC2JCYAaz9Oe/tb1jXj2UAR/C7uRvjneHgJE/SCtm7ks5LNmaUlNhFg2yFV87IfzF 2VF/Vu5y/Y7MDnkR8nudRqPsd0OpR1/6p9OXUA9WaIuiPO1CT031tpnppWGblCZv5e Hii6KRqNFVaNkwbSYGw/PT1F77BxhgDPpF156ch7BDDjGY68Q/C3PSg9ZpVNAehE/Y Hi2h07/JnFoxQ== Message-ID: Date: Wed, 6 Nov 2024 15:13:37 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/8] dt-bindings: clock: imx8m-clock: support spread spectrum clocking From: Krzysztof Kozlowski To: Dario Binacchi Cc: linux-kernel@vger.kernel.org, linux-amarula@amarulasolutions.com, Abel Vesa , Conor Dooley , Fabio Estevam , Krzysztof Kozlowski , Michael Turquette , Peng Fan , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo , Stephen Boyd , devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org References: <20241106090549.3684963-1-dario.binacchi@amarulasolutions.com> <20241106090549.3684963-2-dario.binacchi@amarulasolutions.com> <4bix7me5vaoyhcuffyp4btajmhy7no6ltczoesopaz2fqupyaw@fensx4nn472u> Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 06/11/2024 15:10, Krzysztof Kozlowski wrote: > On Wed, Nov 06, 2024 at 09:57:57AM +0100, Dario Binacchi wrote: >> The patch adds the DT bindings for enabling and tuning spread spectrum >> clocking generation. > > We had long talks about this but nothing of it got reflected in commit > msg. Sorry, I don't remember what I was talking in some particular patch > month ago, so you will get the same questions over and over... > >> >> Signed-off-by: Dario Binacchi >> >> --- >> >> Changes in v3: >> - Added in v3 >> - The dt-bindings have been moved from fsl,imx8m-anatop.yaml to >> imx8m-clock.yaml. The anatop device (fsl,imx8m-anatop.yaml) is >> indeed more or less a syscon, so it represents a memory area >> accessible by ccm (imx8m-clock.yaml) to setup the PLLs. >> >> .../bindings/clock/imx8m-clock.yaml | 46 +++++++++++++++++++ >> 1 file changed, 46 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/clock/imx8m-clock.yaml b/Documentation/devicetree/bindings/clock/imx8m-clock.yaml >> index c643d4a81478..7920393e518e 100644 >> --- a/Documentation/devicetree/bindings/clock/imx8m-clock.yaml >> +++ b/Documentation/devicetree/bindings/clock/imx8m-clock.yaml >> @@ -43,6 +43,40 @@ properties: >> ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx8m-clock.h >> for the full list of i.MX8M clock IDs. >> >> + fsl,ssc-clocks: >> + $ref: /schemas/types.yaml#/definitions/phandle-array >> + description: >> + Phandles of the PLL with spread spectrum generation hardware capability. >> + minItems: 1 >> + maxItems: 4 > > 1. How is it possible that you change spread spectrum of some clocks from > main Clock Controller, while this device is not a consumer of them? > Basically this means that this device does not have these clocks but yet > you claim that it needs to configure spread for them! It's contradictory > to me and nohing got explained in commit msg about it. I am pretty sure > I asked about this alrady. I digged my previous answer and it was pretty clear here: 18:44 You can, but I still have the same concerns. How this device - which does not take any clock input, has no clocks at all - can depend on spread spectrum of some PLLs? Thsi device does not have clocks. 18:50 device has no clocks, I checked now third time 18:50 If device has clocks, it must have clocks property So again, you do not need this property at all. I repeated it multiple times - you are supposed to use clocks property. > > 2. Why is this array flexible in size? > > Best regards, > Krzysztof > Best regards, Krzysztof