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 1D166C4321E for ; Wed, 9 Mar 2022 16:33:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235599AbiCIQdz (ORCPT ); Wed, 9 Mar 2022 11:33:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238827AbiCIQbv (ORCPT ); Wed, 9 Mar 2022 11:31:51 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BE191A276C; Wed, 9 Mar 2022 08:26:31 -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 dfw.source.kernel.org (Postfix) with ESMTPS id A77EE616F3; Wed, 9 Mar 2022 16:26:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB0EFC340E8; Wed, 9 Mar 2022 16:26:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646843190; bh=rl1icRboHEyesR24+3jywPHSGv79vG6tiCm8J9VLWLY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lw9LJzjLcJiQz++swD0ySDkzLfH/GvOcHtOMCm7Aqb0yPkJbrk5TnORH+Q1L1lg9E 5uXr7mgUQgZjwZ9MfZNCSr3zaP4p/zsGdWU+aidiOvdSV0YSOOR6IyZGv4KPn01Icg hMqh7/R+86pmH6Hx9HnnGo3DACktwucDaS3R8usTdMYcupQWIEl+mfrEvZx/SjqP1+ GzUYFKkH9y2Zm0MSCdf43s7ZqXOhnXOe1WvP5jJH1hHmBl64nNiEjtT0GSMELpsSj5 /PDOGzmaFyx9TME1lqOdetryvBuCse8vDKj7LEoydKBXD/9yPnZCQ2zOWUlPqITY6o GsiYJCpmJLGGg== 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 4.14 02/12] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Wed, 9 Mar 2022 11:26:07 -0500 Message-Id: <20220309162618.137226-2-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220309162618.137226-1-sashal@kernel.org> References: <20220309162618.137226-1-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: devicetree@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 0d5679380b2a..70fe6013d17c 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi @@ -484,6 +484,12 @@ 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