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 X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 866A8CA9EC5 for ; Wed, 30 Oct 2019 20:42:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 577D62080F for ; Wed, 30 Oct 2019 20:42:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="YPin++qn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 577D62080F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=free.fr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:In-Reply-To: Date:References:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=3mUexh4YvYn6ctaBeHSXFi/Av9CK0CKiSp6YSRQK9m4=; b=YPin++qnkOPLUb K4FzhsI/EtZcqqyxyVRunE6koi3c467LUcRNObVdgiHZi6yyA+oVjVzBUuYCpSmqpnm0F1xv48BXr hXFYyplqFxDphZ5sBzQLAfJShH5dVW3GNKbNnL1sKy5ibv50Qb9k6j9+PfjkNOsL3rF6jfAq+cMK7 EGKQmGeP7iBjUnM2bXtJgiyyemLUpKZrPbjTl9m8uWZhosdY3fnvQih7DtybhUQS9kZmBjskBZavy EMh4GHVJkbfhHvkALKGWDvMFlFGZWejCBza3ZUDQIa059smEDGTAC72vK+Y7dwIMpdzdsOdskiAfu MqYWp680FFYzfF1+3ADw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iPung-0003IB-Lt; Wed, 30 Oct 2019 20:42:40 +0000 Received: from smtp08.smtpout.orange.fr ([80.12.242.130] helo=smtp.smtpout.orange.fr) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iPune-0003Hf-5I for linux-arm-kernel@lists.infradead.org; Wed, 30 Oct 2019 20:42:39 +0000 Received: from belgarion ([90.55.204.252]) by mwinf5d15 with ME id Kwib210045TFNlm03wib3h; Wed, 30 Oct 2019 21:42:36 +0100 X-ME-Helo: belgarion X-ME-Auth: amFyem1pay5yb2JlcnRAb3JhbmdlLmZy X-ME-Date: Wed, 30 Oct 2019 21:42:36 +0100 X-ME-IP: 90.55.204.252 From: Robert Jarzmik To: Stephen Boyd Subject: Re: [PATCH 35/46] cpufreq: pxa3: move clk register access to clk driver References: <20191018154052.1276506-1-arnd@arndb.de> <20191018154201.1276638-35-arnd@arndb.de> <20191028092327.939C82184C@mail.kernel.org> X-URL: http://belgarath.falguerolles.org/ Date: Wed, 30 Oct 2019 21:42:35 +0100 In-Reply-To: <20191028092327.939C82184C@mail.kernel.org> (Stephen Boyd's message of "Mon, 28 Oct 2019 02:23:26 -0700") Message-ID: <87tv7qm0ck.fsf@belgarion.home> User-Agent: Gnus/5.130008 (Ma Gnus v0.8) Emacs/26 (gnu/linux) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191030_134238_481091_C540780F X-CRM114-Status: GOOD ( 16.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Arnd Bergmann , linux-pm@vger.kernel.org, Viresh Kumar , Linus Walleij , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, Haojian Zhuang , linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Michael Turquette , Daniel Mack Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Stephen Boyd writes: > Quoting Arnd Bergmann (2019-10-18 08:41:50) >> +void pxa3xx_clk_update_accr(u32 disable, u32 enable, u32 xclkcfg, u32 mask) >> +{ >> + u32 accr = ACCR; >> + >> + accr &= ~disable; >> + accr |= enable; >> + >> + ACCR = accr; >> + if (xclkcfg) >> + __asm__("mcr p14, 0, %0, c6, c0, 0\n" : : "r"(xclkcfg)); > > It's just a coprocessor instruction though? I don't see what this has to > do with clks that we model in the kernel? Why can't it just be put in > the cpufreq driver that calls it? I think you forget the "ACCR = accr", which is an MMIO register write. ACCR stands for "Application Subsystem Clock Configuration Register", so I think Arnd is right to put it in here. As for the broader question you ask, about the cpufreq driver, the reason is unfortunately "historic" : pxa3xx cpufreq driver doesn't use the clock framework to set the bus clocks, but does it by directly accessing the registers : old platform, old ways, etc ... Cheers. -- Robert _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel