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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4F02BC432BE for ; Tue, 24 Aug 2021 17:08:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3BAC561BF3 for ; Tue, 24 Aug 2021 17:08:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238865AbhHXRIq (ORCPT ); Tue, 24 Aug 2021 13:08:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:45878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239165AbhHXRGc (ORCPT ); Tue, 24 Aug 2021 13:06:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 434EC61994; Tue, 24 Aug 2021 16:59:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629824387; bh=sRcdw/m1r+YBgbtvwqRQ1X9Gu951mClHv48QPe5NpBc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hU8Y7gszWPh4MLkrk9t2+Z7z08D/HevF0OeInD9dQGIFM96OAepmnrh6ec/YupGLE m4gDQueLIs2UBVSbTpaTfVlGiCH69UHuhikF0NuX3LAH6wy9JeW2NzptXq31r00oiN SofIzZoLKM3DHCFVOms7ctuDMopsKDvgFXtp3ZcMal8lBbycFXFZFcGHm5k68RAz/G gz0QodTJpqRVvGJX7yA/fuIi4T6KkRA1aGsdW3RYwPvyrw4ik2nHH+5fwSwAI4upBg 5atRWaY0ojBHBb3jwaWyED/Z0tsBTXDfTCEkH3zy0ClAUFj/RuPNn3SQSnRhZmIGhr nDazmlc7WHM0Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Marek=20Beh=C3=BAn?= , Viresh Kumar , Sasha Levin Subject: [PATCH 5.10 38/98] cpufreq: armada-37xx: forbid cpufreq for 1.2 GHz variant Date: Tue, 24 Aug 2021 12:58:08 -0400 Message-Id: <20210824165908.709932-39-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210824165908.709932-1-sashal@kernel.org> References: <20210824165908.709932-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.10.61-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.10.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.10.61-rc1 X-KernelTest-Deadline: 2021-08-26T16:58+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marek Behún [ Upstream commit 484f2b7c61b9ae58cc00c5127bcbcd9177af8dfe ] The 1.2 GHz variant of the Armada 3720 SOC is unstable with DVFS: when the SOC boots, the WTMI firmware sets clocks and AVS values that work correctly with 1.2 GHz CPU frequency, but random crashes occur once cpufreq driver starts scaling. We do not know currently what is the reason: - it may be that the voltage value for L0 for 1.2 GHz variant provided by the vendor in the OTP is simply incorrect when scaling is used, - it may be that some delay is needed somewhere, - it may be something else. The most sane solution now seems to be to simply forbid the cpufreq driver on 1.2 GHz variant. Signed-off-by: Marek Behún Fixes: 92ce45fb875d ("cpufreq: Add DVFS support for Armada 37xx") Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin --- drivers/cpufreq/armada-37xx-cpufreq.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c index e4782f562e7a..2de7fd18f66a 100644 --- a/drivers/cpufreq/armada-37xx-cpufreq.c +++ b/drivers/cpufreq/armada-37xx-cpufreq.c @@ -102,7 +102,11 @@ struct armada_37xx_dvfs { }; static struct armada_37xx_dvfs armada_37xx_dvfs[] = { - {.cpu_freq_max = 1200*1000*1000, .divider = {1, 2, 4, 6} }, + /* + * The cpufreq scaling for 1.2 GHz variant of the SOC is currently + * unstable because we do not know how to configure it properly. + */ + /* {.cpu_freq_max = 1200*1000*1000, .divider = {1, 2, 4, 6} }, */ {.cpu_freq_max = 1000*1000*1000, .divider = {1, 2, 4, 5} }, {.cpu_freq_max = 800*1000*1000, .divider = {1, 2, 3, 4} }, {.cpu_freq_max = 600*1000*1000, .divider = {2, 4, 5, 6} }, -- 2.30.2