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 18EE3C433FE for ; Mon, 21 Mar 2022 13:56:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348371AbiCUN51 (ORCPT ); Mon, 21 Mar 2022 09:57:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348328AbiCUN4M (ORCPT ); Mon, 21 Mar 2022 09:56:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 589E6167DC; Mon, 21 Mar 2022 06:54:37 -0700 (PDT) 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 E7CF96126E; Mon, 21 Mar 2022 13:54:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 07723C340E8; Mon, 21 Mar 2022 13:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647870876; bh=s316ygrdqc1xWuck3n4IO4eDMiOmMRS+C0SCMzq6M5s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AZ5tPpgEurU+aDYxNESB3aFrb3ehBYsMjEDtZ+Y9xO+MRI9p+3OgOSSOH1V7YPV92 NcN94sZWueE3/YTrRbwsS9HdJnTuVNobhzEX1V2HAsfpAmYXKShToJf0P0tB5OShIk 1TvIW6Ou7orb3nOlPqJwQugqqGUtph5JuRc/q0d4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Quentin Schulz , Jakob Unterwurzacher , Quentin Schulz , Heiko Stuebner , Sasha Levin Subject: [PATCH 4.14 04/22] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Mon, 21 Mar 2022 14:51:35 +0100 Message-Id: <20220321133217.734580952@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220321133217.602054917@linuxfoundation.org> References: <20220321133217.602054917@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 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 @@ }; &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