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 222B0C433EF for ; Thu, 17 Mar 2022 12:58:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234453AbiCQM7a (ORCPT ); Thu, 17 Mar 2022 08:59:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234335AbiCQMz7 (ORCPT ); Thu, 17 Mar 2022 08:55:59 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70C72BB920; Thu, 17 Mar 2022 05:54:05 -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 0FE56614F0; Thu, 17 Mar 2022 12:54:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 02807C340EF; Thu, 17 Mar 2022 12:54:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647521644; bh=DPdfF6q9H15BXcu0xyHzF22kFQv23DsT8xa/YMq2E1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S05oLSeXKc3hOfghWJtg+hbBpaQ6c9Nb4bB23q5baJfHdGMuQZZ7vy8+qW5KVM3La oz/BBKqnOXmiVdSqJJ+pEle0PzgfZ+/EXMzka654i6oxCWFH2Y/h9FVMWyAAAsJGal N89kd8zJljBvM25F2fnFKyxCTS2qnLRWKja4U24k= 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 5.16 06/28] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Thu, 17 Mar 2022 13:45:57 +0100 Message-Id: <20220317124526.953096814@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220317124526.768423926@linuxfoundation.org> References: <20220317124526.768423926@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 002ece51c3ba..08fa00364b42 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi @@ -439,6 +439,12 @@ }; &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