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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 9735CCA9EA0 for ; Mon, 28 Oct 2019 08:36:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D77D20717 for ; Mon, 28 Oct 2019 08:36:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572251766; bh=YSz7TfslhiFwmoaN1bPaiGLyGWgIdmnawIFyeNvBbtU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=OsSYJubwmNvN2eFBxbmqf0OBip0OY9fLJgcuQqz876eK2zsFkwx5MPI7UAZVSF8PS kNbtWXJze76whK+xVfzjIz7yBUbhe601OcH9WhbilyBAtpOQOE750Zu+Eawc/nDuaw HWpT5bwWobxkqacSR+Lqwq2EHDGGjbu3ifN92K/U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732003AbfJ1IgF (ORCPT ); Mon, 28 Oct 2019 04:36:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:53824 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732023AbfJ1IgF (ORCPT ); Mon, 28 Oct 2019 04:36:05 -0400 Received: from dragon (98.142.130.235.16clouds.com [98.142.130.235]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 913C220650; Mon, 28 Oct 2019 08:35:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572251765; bh=YSz7TfslhiFwmoaN1bPaiGLyGWgIdmnawIFyeNvBbtU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VfjtwdY4B4l+k3YieRfLebQ0T/q+/R30MRXAiyVe1v/8sglkt3uLbuGJ3YPOeyopS xdSTCV2Q2HDdWnpA8UBTp7WNAoTfQZ50T7ThHZFTsb3z2rIUwmPT3lPNivgD58PKlk yhm87rSAYBKqgAVQ+DE/PUgkfNEhwzzwRp3Y5gQA= Date: Mon, 28 Oct 2019 16:35:40 +0800 From: Shawn Guo To: Leonard Crestez , Stephen Boyd Cc: Michael Turquette , Dong Aisheng , Fabio Estevam , Jacky Bai , Anson Huang , Abel Vesa , linux-clk@vger.kernel.org, kernel@pengutronix.de, linux-imx@nxp.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] clk: imx8m: Use SYS_PLL1_800M as intermediate parent of CLK_ARM Message-ID: <20191028083539.GT16985@dragon> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org On Tue, Oct 22, 2019 at 10:21:28PM +0300, Leonard Crestez wrote: > During cpu frequency switching the main "CLK_ARM" is reparented to an > intermediate "step" clock. On imx8mm and imx8mn the 24M oscillator is > used for this purpose but it is extremely slow, increasing wakeup > latencies to the point that i2c transactions can timeout and system > becomes unresponsive. > > Fix by switching the "step" clk to SYS_PLL1_800M, matching the behavior > of imx8m cpufreq drivers in imx vendor tree. > > This bug was not immediately apparent because upstream arm64 defconfig > uses the "performance" governor by default so no cpufreq transitions > happen. > > Fixes: ba5625c3e272 ("clk: imx: Add clock driver support for imx8mm") > Fixes: 96d6392b54db ("clk: imx: Add support for i.MX8MN clock driver") > > Cc: stable@vger.kernel.org > Signed-off-by: Leonard Crestez Acked-by: Shawn Guo Stephen, I assume that you will pick up this one as a fix. Shawn