From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6A4C0502BE; Wed, 24 Sep 2025 13:13:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758719606; cv=none; b=NKjVOiJ10mQt+sXXu2S7qBQBEDS2ILiudbzafsId/04jYgMPvMeY8WkBstRpS3fGpNCxW88R+PpsGmqUQeD7gZybryOVAv8qXJnsZuHsf+soWftHNzVnBSLwj84S/5HRky51dlj5BgTOq1DOj5z1KV5LUClRkv0pcfZ47BI/KLM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758719606; c=relaxed/simple; bh=PaVdJZ/PeqgEBbm90xkNqO1qgjBPVF79+jKWROcFGY0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EP49ki1hjQXSEd5+/QSIa1t2Pq9EzH8TixU0VZpXhRl0rMXCPjJcyaxwhbP6A7OjPNIz+j3qrrbK7v1ZKQjpNDoQPXtIEPC0rSuGFOPYSTgGYY3Yt8+mJBNTHL6FGoOI9OozkPzfVhMYEcWlfSWkTX10jyFxdH+mFnUOkVKmANQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com; spf=none smtp.mailfrom=foss.arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=foss.arm.com 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 CD41C106F; Wed, 24 Sep 2025 06:13:15 -0700 (PDT) Received: from bogus (e133711.arm.com [10.1.196.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0C7953F5A1; Wed, 24 Sep 2025 06:13:20 -0700 (PDT) Date: Wed, 24 Sep 2025 14:13:18 +0100 From: Sudeep Holla To: Peng Fan Cc: Sebin Francis , Michael Turquette , Sudeep Holla , Stephen Boyd , Cristian Marussi , "Marco Felsch" , Rob Herring , "Krzysztof Kozlowski" , Conor Dooley , "Brian Masney" , Dan Carpenter , Geert Uytterhoeven , "linux-clk@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "arm-scmi@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "devicetree@vger.kernel.org" Subject: Re: [PATCH v4 5/5] clk: scmi: Support Spread Spectrum for NXP i.MX95 Message-ID: <20250924-dark-super-gharial-246400@sudeepholla> References: <20250915-clk-ssc-version1-v4-0-5a2cee2f0351@nxp.com> <20250915-clk-ssc-version1-v4-5-5a2cee2f0351@nxp.com> <5f508f1d-2d08-4687-86cd-d1944caa0a49@ti.com> <082735e7-956b-4574-952e-06ba69db41f1@ti.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Sep 24, 2025 at 11:43:56AM +0000, Peng Fan wrote: > > Subject: Re: [PATCH v4 5/5] clk: scmi: Support Spread Spectrum for > > NXP i.MX95 > ... > > >>> SCMI_CLOCK_CFG_OEM_START = 0x80, > > >>> + SCMI_CLOCK_CFG_IMX_SSC = 0x80, > > >> > > >> TI is also planning to implement the same in our upcoming platform. > > >> so can we use a generic ID instead of vender specfic message ID? > > > > > > I tried to push to new generic ID [1] in half a year ago, but in the > > > end ARM decided not to add generic ID for spread spectrum support. > > > > > > To i.MX, it is too late to use a generic ID and waiting spec, i.MX > > > firmware has been public for quite some time and passed several > > external releases. > > > So I need to use what our firmware adds and spec allows: vendor > > > extension. > > > > Thanks for the quick response, > > Since this implementation is specific to i.MX, can you move this to a > > vendor specific file, so that it will not break i.MX's firmware and TI can > > implement SSC in TI specific file. > > i.MX has encountered issue with pinctrl-scmi.c and pinctrl-imx-scmi.c > both supports SCMI PINCTRL. Current linux scmi does not support > both drivers built in kernel image, because scmi devlink issue. > > Sudeep said he would address the devlink issue in 6.19 cycle. > Yes it is a different issue IMO and nothing related to this. > Given the current situation, I'm hesitant to introduce a new driver > saying clk-imx-scmi.c. > Yes please don't, and I don't see a strong reason for that(yet). Unlike vendor protocol, there is no way we can no upfront how the vendors can use this in their own colourful way. So I am not sure if we start building something generic from the start or refactor as more vendors start using it. Hard to decide 🙁. Lets see, need to think a bit. If Peng or Sebin or others have some idea, please propose or start the discussion so that we can evaluate the approach. -- Regards, Sudeep