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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 F0F6FC33CB6 for ; Thu, 16 Jan 2020 17:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CBA49246F3 for ; Thu, 16 Jan 2020 17:47:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196835; bh=sgOoolRsRLW4pkiLoqF6nOV5AmgG6FrkopMUr9rx9Co=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ky8PSti5xCjg7xN0JBgpV67rlcbvL24wfbwxJgnv6BWY4YdiwaGudPjeuD77LCrHI j9mfJ5xDXEZzXGZ6OEso8/xtKaVEbo+Mu41pu0mwO7jVLWlWvQi1tj1B3IiQEfBrPu 8R4S/9SCXbP4qHrox2vbK7KjSeZBCUDve3TeJwTs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406856AbgAPRq7 (ORCPT ); Thu, 16 Jan 2020 12:46:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:40244 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406849AbgAPRq6 (ORCPT ); Thu, 16 Jan 2020 12:46:58 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 199C4246B4; Thu, 16 Jan 2020 17:46:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196818; bh=sgOoolRsRLW4pkiLoqF6nOV5AmgG6FrkopMUr9rx9Co=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=w4VxprzXG/WNk5RZUe3kH+jrFaf8PC3DF/4xhUebXipGKO9a0etkRf7XVmj0FCFr3 NcJTJ3/bP03e71RWNYl1O7+0tCgZTHAoNjwlsyaL4uq14tWgPFIALb75SvjQi2MvFJ qilX860Bpzotg6M1pi44nAb1hc+8DdDn9erDbiqw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Andre Przywara , Liviu Dudau , Sudeep Holla , Sasha Levin , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 173/174] arm64: dts: juno: Fix UART frequency Date: Thu, 16 Jan 2020 12:42:50 -0500 Message-Id: <20200116174251.24326-173-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116174251.24326-1-sashal@kernel.org> References: <20200116174251.24326-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Andre Przywara [ Upstream commit 39a1a8941b27c37f79508426e27a2ec29829d66c ] 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: Sasha Levin --- arch/arm64/boot/dts/arm/juno-clocks.dtsi | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/boot/dts/arm/juno-clocks.dtsi b/arch/arm64/boot/dts/arm/juno-clocks.dtsi index 25352ed943e6..00bcbf7688c7 100644 --- 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"; }; -- 2.20.1