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 49D0BC433F5 for ; Mon, 21 Mar 2022 14:00:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348512AbiCUOBw (ORCPT ); Mon, 21 Mar 2022 10:01:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348697AbiCUN6L (ORCPT ); Mon, 21 Mar 2022 09:58:11 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36E1B174B95; Mon, 21 Mar 2022 06:56:13 -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 ams.source.kernel.org (Postfix) with ESMTPS id 34558B816DA; Mon, 21 Mar 2022 13:56:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 66DF6C340E8; Mon, 21 Mar 2022 13:56:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647870968; bh=i0Qo3fX/ApQqEBwCQ21tsIoIkznHhRd0w9qXkrP3dvg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xRwxjBIgz1DZMSohBg+H6dUqC6DUUeR1428WXwpZ/m1qIoqTOGx0OPXEJkL39Gdql bHR0tstl6DNhd8KKaXPj4Jieqw0pxDQADFsSohxXeK/Y8ZarwApYSlOYgH+Jg0kEUE +1P/o/5VlyLp/RloznbAuCaRaPtt61mvSgLcLJ68= 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 4.19 06/57] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Mon, 21 Mar 2022 14:51:47 +0100 Message-Id: <20220321133222.172580326@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220321133221.984120927@linuxfoundation.org> References: <20220321133221.984120927@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 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 @@ }; &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