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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6B8FC46467 for ; Wed, 9 Mar 2022 16:50:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237219AbiCIQss (ORCPT ); Wed, 9 Mar 2022 11:48:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238006AbiCIQbS (ORCPT ); Wed, 9 Mar 2022 11:31:18 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E16AF192C95; Wed, 9 Mar 2022 08:25:30 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D2567B82020; Wed, 9 Mar 2022 16:25:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E701C340E8; Wed, 9 Mar 2022 16:25:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646843125; bh=K9gceViHzNAZRZsRqEmIjzn7fQTvsVlXZG/p6NcdhHk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oNqnmikp8Wio4YDMmGaqZ4TqlScAIaJ8FpJZMCCGYIjdxfK4i1lGYLWXRpWH7vT/i +2qnVjSRNvi/gzIdyeqxIJ9DvRkdoYyrP3b+ZI9CPK7lDze9roZrSEXWMQQWExUVs0 yORXtyGjk/GT6jDup4sis083EFQf4mMwCvferP7FZV+fmyS2un2/AduGfbOlrwOHID 5//yL3budJFyTBFvvzymcNT6xb4AK1yC9YA3633A46iZ6PUuEPLzNFwM1Mc52JWasu kjYhEoIkH0x83kZ6Imc4A2BzbxRJE0m724DHM++eqqEtD4WywWl/XY0/ze8myqxN+j 1PKKY/Oy13P5g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jakob Unterwurzacher , Quentin Schulz , Quentin Schulz , Heiko Stuebner , Sasha Levin , robh+dt@kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org Subject: [PATCH AUTOSEL 4.19 03/14] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Wed, 9 Mar 2022 11:24:56 -0500 Message-Id: <20220309162508.137035-3-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220309162508.137035-1-sashal@kernel.org> References: <20220309162508.137035-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jakob Unterwurzacher [ Upstream commit 62966cbdda8a92f82d966a45aa671e788b2006f7 ] There are signal integrity issues running the eMMC at 200MHz on Puma RK3399-Q7. Similar to the work-around found for RK3399 Gru boards, lowering the frequency to 100MHz made the eMMC much more stable, so let's lower the frequency to 100MHz. It might be possible to run at 150MHz as on RK3399 Gru boards but only 100MHz was extensively tested. Cc: Quentin Schulz Signed-off-by: Jakob Unterwurzacher Signed-off-by: Quentin Schulz Link: https://lore.kernel.org/r/20220119134948.1444965-1-quentin.schulz@theobroma-systems.com Signed-off-by: Heiko Stuebner Signed-off-by: Sasha Levin --- arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi index b155f657292b..ce1320e4c106 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi @@ -468,6 +468,12 @@ vcc5v0_host_en: vcc5v0-host-en { }; &sdhci { + /* + * Signal integrity isn't great at 200MHz but 100MHz has proven stable + * enough. + */ + max-frequency = <100000000>; + bus-width = <8>; mmc-hs400-1_8v; mmc-hs400-enhanced-strobe; -- 2.34.1