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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2A901C0218C for ; Mon, 27 Jan 2025 07:44:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=v/QZH2w+1iqi7M9IIeYOwhVyB4QUWIesyh3k9pepWFA=; b=qcUR7YX8BaG5E2T6wv4NMA/5sA bFonTqCPWMnqnB/i9NzIUudyXTj8oDl/WX7i2heM9w8Zx5pXns4iEW1tdy/0GJAFmRlkBvkQfsZ58 Rx6TAX88l//S5HAo3/140Z0QIIrUoUKE4fbzjxGGntZ/9O+StFxP0rzhFX9KuZws4JzqEDQqmB9WS Z7t+GvTNXv/MwpkA+beHzQQowTDZ43hfH6GohuCy/vLwU16N12UujKT7n0BeFoNq8ss0d/9naPzTZ r1OlPlDRrHsSKwLAe8pEPyEIEwkX2Nb3DGweUsKIg+6P4qpdSSitbOdZre05Yp2akBApTzfwDWCP9 b8tLu4vA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tcJn3-00000001pmw-2mhZ; Mon, 27 Jan 2025 07:44:13 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tcJli-00000001piw-3My7 for linux-arm-kernel@lists.infradead.org; Mon, 27 Jan 2025 07:42:52 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id EFFDC5C48D5; Mon, 27 Jan 2025 07:42:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CF08DC4CED2; Mon, 27 Jan 2025 07:42:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737963769; bh=aIqnWZ8NSvlj83SaDa04/QPb9wxsdmjf4gvmkd5sQ1g=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=Kv61wQIF65ae5uXTDGFxzXby3iGGij7165vsmlQMe7gWJnvVFhEpWMjbA0q7NVTo8 B5LAtME87khYni+7t5UAf+8MrQhbx4Xuqqtsox5VAXBHrgbmcG69G0Xe8GOCVvoo3G i6MXGQRg414BxRQeui4euf3oqbo/S37V5+RyQ7Ue5Hj4IHszioVpHzJDbgpqUKOSPT m5XX1PkZbPC9VZQzy0G4C4WNth51MAXQY0axei+jGm5qL2HnGBAJlCRnEDptG4UCn4 7WBxc0ign6mbRUxlkCp2tfjscFiuW7lVjcqcFkC5TejzTYkMVd/PmKuhno5VIINXhw mAX7SL9LtuDow== Message-ID: <74663d9d-364e-4db3-b18a-1068e2845215@kernel.org> Date: Mon, 27 Jan 2025 08:42:41 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/3] clk: Support spread spectrum and use it in clk-scmi To: Dario Binacchi , "Peng Fan (OSS)" Cc: Michael Turquette , Stephen Boyd , Russell King , Sudeep Holla , Cristian Marussi , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, arm-scmi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Rob Herring , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , imx@lists.linux.dev, Peng Fan References: <20250124-clk-ssc-v1-0-2d39f6baf2af@nxp.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250126_234250_935407_30FA1A3C X-CRM114-Status: GOOD ( 20.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 25/01/2025 13:58, Dario Binacchi wrote: > On Fri, Jan 24, 2025 at 2:19 PM Peng Fan (OSS) wrote: >> >> - Introduce clk_set_spread_spectrum to set the parameters for enabling >> spread spectrum of a clock. >> - Parse 'assigned-clock-sscs' and configure it by default before using the >> clock. The pull request for this property is at [1] >> This property is parsed before parsing clock rate. >> >> - Enable this feature for clk-scmi on i.MX95. >> This may not the best, since checking machine compatibles. >> I am thinking to provide an API scmi_get_vendor_info, then driver >> could use it for OEM stuff, such as >> if (scmi_get_vendor_info returns NXP_IMX) >> ops->set_spread_spectrum = scmi_clk_set_spread_spectrum_imx; >> > > I wonder if your solution is truly generic or merely a generalization > of your use case, which seems significantly simpler compared to what Please come with specific arguments why this is not generic enough, not just FUD. Does it fit your case? If not, what would had to be changed? These are the comments needed to actually work on generic solution. > happens on the i.MX8M platform, as discussed in thread > https://lore.kernel.org/lkml/PAXPR04MB8459537D7D2A49221D0E890D88E32@PAXPR04MB8459.eurprd04.prod.outlook.com/, > or on the STM32F platform, where parameters are not written directly > to registers but are instead used in calculations involving the > parent_rate and the PLL divider, for example. > > I am the author of the patches that introduced spread spectrum > management for the AM33x and STM32Fx platforms, as well as the > series, still pending acceptance, for the i.MX8M. > From my perspective, this functionality varies significantly > from platform to platform, with key differences that must be > considered. So what exactly varies? Come with specifics. To me look addressing exactly the same. Best regards, Krzysztof