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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 B31E5C2D0C1 for ; Thu, 19 Dec 2019 05:28:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7AA2A222C2 for ; Thu, 19 Dec 2019 05:28:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qiLztxrZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726976AbfLSF2t (ORCPT ); Thu, 19 Dec 2019 00:28:49 -0500 Received: from mail-pf1-f193.google.com ([209.85.210.193]:38241 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbfLSF2s (ORCPT ); Thu, 19 Dec 2019 00:28:48 -0500 Received: by mail-pf1-f193.google.com with SMTP id x185so2531853pfc.5; Wed, 18 Dec 2019 21:28:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=lWOehvqpXv6OawJrlmRDByhBUZ+tWPDIeTBZc/6GCfQ=; b=qiLztxrZMsI9XLuisxdv0QIs5ojPlPFLlGH1KBeFxij5Kvfk4r+LDXcJyOGzUBRoVT 3cuS3GoP+j5+kgQM6jobGYKl3lRufCq+2VL1ovUkBtyT7To001eRSD7hefvVj8oNeeGB KlqK/eEl0iFN2yOPedfqa3F/1ADCzfk09o0D5YizkuQGGlRDePgcSDcNDKNSosYqtQp1 L3vu4zpg2JAZ6XNRoIhdX0Fg41SFkyc2/p/FGGTcPeDDoXzGwxqg0qGGCl67RASYsDdU 8Z80zMOXxg50eYj5c4jgjkqFS0N/vJoFl019Zyty40mSp33FZrqKO+/+2ewYG8WnxlA8 B7xA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=lWOehvqpXv6OawJrlmRDByhBUZ+tWPDIeTBZc/6GCfQ=; b=uPdebBpKAt88SXTa0wlPznQ7LFN5i0cMZXQtZbSLvcDNDcHHXmCYWmYFTY6tOQDJ3G 1SYDBUVTGowgiXnc23SNYMzt7RjPUnOsEpHXhKr7YkFCTLDjJn0beaS8rO89ZVd8Hrko Ics8fsRm+ckGwdSAWQA8MKeSo6dZ1Kbxd7PEJVaQBR06g49ANJ8vzMJ5hTxyj00NILxO tfeejyx+gkLj4V6uC3ribFnhAaZ0+Yg5/MjOwf+QscifZKkUv9BRb9HuxrKb9Yi8ePB2 9BPIsFE93vArD1Smd/XdAw856/BG25L6qcMwoIkLIL6ihP89NxrfVtqp/fa8+YU/nY4q r1sw== X-Gm-Message-State: APjAAAXsIviISXrCcZrX1QF4MHdzgCpjJurvEglWeSVi/TS1qkeXUkpx /8MOF2/50ipQrf6eolBDQ2o+eIbgtPU= X-Google-Smtp-Source: APXvYqzGeo5jRRDBKjCYPgpdsBTeYU9wvWq7UqMVJVQnl/d5yhSP0a36sKDjfd5cEC5gGaYgT9Nquw== X-Received: by 2002:a63:5950:: with SMTP id j16mr7441814pgm.314.1576733327995; Wed, 18 Dec 2019 21:28:47 -0800 (PST) Received: from vipul.mgc.mentorg.com (nat-sch.mentorg.com. [139.181.36.34]) by smtp.googlemail.com with ESMTPSA id j22sm4818129pji.16.2019.12.18.21.28.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Dec 2019 21:28:47 -0800 (PST) From: Vipul Kumar To: Daniel Lezcano , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, Stable , Cedric Hombourger , Vipul Kumar , Srikanth Krishnakar , Vipul Kumar Subject: [V2] x86/tsc: Unset TSC_KNOWN_FREQ and TSC_RELIABLE flags on Intel Bay Trail SoC Date: Thu, 19 Dec 2019 10:58:25 +0530 Message-Id: <20191219052825.4146-1-vipulk0511@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vipul Kumar 'commit f3a02ecebed7 ("x86/tsc: Set TSC_KNOWN_FREQ and TSC_RELIABLE flags on Intel Atom SoCs")', causing time drift for Bay trail SoC. These flags are set for SoCs having cpuid_level 0x15 or more. Bay trail is having cpuid_level 0xb. So, unset both flags to make sure the clocksource calibration can be done. Signed-off-by: Vipul Kumar Cc: # 4.14+ --- - Changes in v2: - Added linux-stable along with kernel version in CC --- arch/x86/kernel/tsc_msr.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c index e0cbe4f2af49..1ca27c28db98 100644 --- a/arch/x86/kernel/tsc_msr.c +++ b/arch/x86/kernel/tsc_msr.c @@ -112,6 +112,9 @@ unsigned long cpu_khz_from_msr(void) lapic_timer_period = (freq * 1000) / HZ; #endif + if (boot_cpu_data.cpuid_level < 0x15) + return res; + /* * TSC frequency determined by MSR is always considered "known" * because it is reported by HW. -- 2.20.1