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 4A917C43214 for ; Tue, 24 Aug 2021 17:26:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3647A61247 for ; Tue, 24 Aug 2021 17:26:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241035AbhHXR1J (ORCPT ); Tue, 24 Aug 2021 13:27:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:60518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239937AbhHXRYA (ORCPT ); Tue, 24 Aug 2021 13:24:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E1EAE61B27; Tue, 24 Aug 2021 17:03:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629824629; bh=yGpHqiBGaRE9YFKtU/zWC4lpZWxkBtcp73H+QXL0ftM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h2TqydCxzSfv9jveYQCDu8ZI5pnM6Rg2AgKZ0fvZJZ0LUaG7xTH98hnfAvcfOIWQo DCLLqr+TMq7BQlMj1+rpUKk3WE8qVFmWwFYRLvtwKHrg6gV5oqhv70d8VxgYM3w786 Lge7qtMs03JJT8M7XuMt97DJR7TflbwEi79na9WAwW1+Tz70FoYLAradblFxOhxxpI yZ/N7elQKaK7jL5aoJ0PsvGNyfq/foFZwvURZDLKFFMUwVfFz+ZUolfxlkmfLvUGIS JIUZugxMteH+uMbnxm0ik9f5Jty3Af+wziK5mXTVL+qUvj9pY03WmRe+jHRn3Dr5ra 1lQUgzd3Jl5fg== 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 4.19 60/84] cpufreq: armada-37xx: forbid cpufreq for 1.2 GHz variant Date: Tue, 24 Aug 2021 13:02:26 -0400 Message-Id: <20210824170250.710392-61-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210824170250.710392-1-sashal@kernel.org> References: <20210824170250.710392-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.19.205-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.19.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.19.205-rc1 X-KernelTest-Deadline: 2021-08-26T17:02+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 a36452bd9612..31b5655419b4 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