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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham 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 018EBC10F11 for ; Wed, 10 Apr 2019 14:18:13 +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 C44BC20850 for ; Wed, 10 Apr 2019 14:18:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="bk7kcWoR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C44BC20850 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com 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:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=B8IkmLm+DlrcW8FAssCdAmnUEXRQnMC3k8vidabZwDI=; b=bk7kcWoRNq1Auh WhhJoKuwgznUt3XHnrl9LWfoft3KSUGU44pf9F0AVpm79LE/QZIyEXqh1/D4iGExSi17QX163SnFM 7J04Zo35aIt1WWe2yX9PTOnv2nAIqrrWlDNXyfPhNwprBAODwqYoinssd74zgshZ8CrOi9QWTp2lY RjZVjgawME1fKU8Cxgy+B91szwAOkl8u0ZUrxDpdM/qJoRq56NBV4I5sYJpwsbeaj52h53mwHecdk x+wAMVzsbBC6cyu7G1xEGJpXf2wn1XI01EiPy1si9Ta3EdgBOIRVgyzuvZ0s4IDdCl/oVvvVGtmem eS1fHUVUPubTKlVLfLVA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hEE3I-0000W7-24; Wed, 10 Apr 2019 14:18:12 +0000 Received: from relay3-d.mail.gandi.net ([217.70.183.195]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hEE3E-0000Vk-3c for linux-arm-kernel@lists.infradead.org; Wed, 10 Apr 2019 14:18:09 +0000 X-Originating-IP: 109.213.33.177 Received: from localhost (alyon-652-1-42-177.w109-213.abo.wanadoo.fr [109.213.33.177]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay3-d.mail.gandi.net (Postfix) with ESMTPSA id A817260008; Wed, 10 Apr 2019 14:18:05 +0000 (UTC) Date: Wed, 10 Apr 2019 16:18:05 +0200 From: Alexandre Belloni To: Vladimir Zapolskiy Subject: Re: LPC3250 periph clock at 13MHz instead of 10.4MHz Message-ID: <20190410141805.GE3578@piout.net> References: <20190212165221.GA10129@piout.net> <20190410134443.GD3578@piout.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190410134443.GD3578@piout.net> User-Agent: Mutt/1.11.3 (2019-02-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190410_071808_298281_6C50504A X-CRM114-Status: GOOD ( 17.91 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Gregory CLEMENT , linux-arm-kernel@lists.infradead.org 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 On 10/04/2019 15:44:43+0200, Alexandre Belloni wrote: > Hi Vladimir, > > On 13/02/2019 19:21:44+0200, Vladimir Zapolskiy wrote: > > > Am I missing something? > > > > > > > I think I encountered quite a similar issue previously, but under another > > circumstances, when I begin to modify HCLK PLL clock rate, can you check > > my comment at https://lore.kernel.org/linux-clk/56D685F6.5060400@mleia.com/ > > and verify if it's about the same problem? > > > > Since the problem hits you also, I plan to spend some time on this weekend > > to capture more details, fortunately there is a known workaround to pin > > UART input clock rate to 13MHz, it might be desired to carve it in the code. > > > > I'm pretty sure this is the same issue and that it doesn't only affect > the UARTs but also timers. > > The 2.6.27.8 kernel code would indicated that the timers are only driven > by sysclk, that is either 13MHz from the oscillator or 13.008896 from > PLL397. I'm wondering how many other peripherals are affected. > You'll note that this is also true for the watchdog, the driver has: // NOTE - the driver only uses this value if it can't get the clock rate from the clk_ drivers #define WDOG_COUNTER_RATE 13000000 /*the counter clock is 13 MHz fixed */ -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel