From patchwork Wed Jan 22 09:29:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 233380 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=-5.7 required=3.0 tests=DATE_IN_PAST_03_06, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 5A17BC2D0DB for ; Wed, 22 Jan 2020 13:29:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 28472205F4 for ; Wed, 22 Jan 2020 13:29:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579699745; bh=xDfirEVkKa3S5RImQWGG1TGOLnNlHUP/nL7HMGpbgog=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=17cYNHsulCz0Ee5EL7VC/mOF80HK8eBhaPmXRqrj1KxGtTK/3kzXPD96CMfs44CYB 1UNDyiD+IjDIBkXipt726n6FIWylbYr0ea60onz+2HZGJzpBh9VBda1db2g6wnOyV1 EDOnxHFoEGolsu415j2xJ8BPtlmqegSF3IwfZSrE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729464AbgAVN2C (ORCPT ); Wed, 22 Jan 2020 08:28:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:49912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729085AbgAVN2C (ORCPT ); Wed, 22 Jan 2020 08:28:02 -0500 Received: from localhost (unknown [84.241.205.26]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 07029205F4; Wed, 22 Jan 2020 13:28:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579699681; bh=xDfirEVkKa3S5RImQWGG1TGOLnNlHUP/nL7HMGpbgog=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wn+Zg1xJ3NZ/FSWiePjz+bbcapMuWo590O2ujagrliZ8nDoDfAHXIUKVb8/WJgBCB Xm7ouWrqB1cyycs6LCCTe+rhXdWDDXrvTSucT8lEckUcqf9y7dGwVFz5UDVjmnpcAL yMwk6SmNOyCDxxdq+08dXUWthhxcqKX4LwiBIV64= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andre Przywara , Liviu Dudau , Sudeep Holla Subject: [PATCH 5.4 190/222] arm64: dts: juno: Fix UART frequency Date: Wed, 22 Jan 2020 10:29:36 +0100 Message-Id: <20200122092847.285024823@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200122092833.339495161@linuxfoundation.org> References: <20200122092833.339495161@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andre Przywara commit 39a1a8941b27c37f79508426e27a2ec29829d66c upstream. Older versions of the Juno *SoC* TRM [1] recommended that the UART clock source should be 7.2738 MHz, whereas the *system* TRM [2] stated a more correct value of 7.3728 MHz. Somehow the wrong value managed to end up in our DT. Doing a prime factorisation, a modulo divide by 115200 and trying to buy a 7.2738 MHz crystal at your favourite electronics dealer suggest that the old value was actually a typo. The actual UART clock is driven by a PLL, configured via a parameter in some board.txt file in the firmware, which reads 7.37 MHz (sic!). Fix this to correct the baud rate divisor calculation on the Juno board. [1] http://infocenter.arm.com/help/topic/com.arm.doc.ddi0515b.b/DDI0515B_b_juno_arm_development_platform_soc_trm.pdf [2] http://infocenter.arm.com/help/topic/com.arm.doc.100113_0000_07_en/arm_versatile_express_juno_development_platform_(v2m_juno)_technical_reference_manual_100113_0000_07_en.pdf Fixes: 71f867ec130e ("arm64: Add Juno board device tree.") Signed-off-by: Andre Przywara Acked-by: Liviu Dudau Signed-off-by: Sudeep Holla Signed-off-by: Greg Kroah-Hartman --- arch/arm64/boot/dts/arm/juno-clocks.dtsi | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/arm64/boot/dts/arm/juno-clocks.dtsi +++ b/arch/arm64/boot/dts/arm/juno-clocks.dtsi @@ -8,10 +8,10 @@ */ / { /* SoC fixed clocks */ - soc_uartclk: refclk7273800hz { + soc_uartclk: refclk7372800hz { compatible = "fixed-clock"; #clock-cells = <0>; - clock-frequency = <7273800>; + clock-frequency = <7372800>; clock-output-names = "juno:uartclk"; };