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 C376CC47084 for ; Wed, 9 Mar 2022 16:32:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235425AbiCIQdv (ORCPT ); Wed, 9 Mar 2022 11:33:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237255AbiCIQaj (ORCPT ); Wed, 9 Mar 2022 11:30:39 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD19415C9F2; Wed, 9 Mar 2022 08:24:16 -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 AFBDF6195B; Wed, 9 Mar 2022 16:23:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72D72C340F7; Wed, 9 Mar 2022 16:23:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646843033; bh=iW0d5jYTr5uhwSlZKDqadiIGanQlhVOoTlRuLUDGIHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s4suJoNiTIXn7waYRQ+3EW62ptc9x2v0ouE1zCNtCakzf/NSD4u0vo6HAI9R2oABF 81kHMNrxt0U/egSAZ1S5YG4rq2WjfGBtjK2ul5pa5UV2j1rT9d6qZmcsOznIefLs5e cDiwvwISWHbhK/GPOlGNLnUnr10Cbp0g7GjkyZSsIOuVLXrpdrrjmgIQUd7mVDSzvO aOT/FvRLhnYBV9OvG7E4gVXA9Go/WwOcrrsMnYaP0FvmMuxJaYNKjF6cq2PDpeIYZ5 TI9+Wcum0PJH7BSO9B3RBLYEsxjknWtQvly9u0minRB5ZyjRQNroFLwJNECndnO2KD +0wsoLa8EEsmQ== 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 5.4 03/19] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Wed, 9 Mar 2022 11:23:20 -0500 Message-Id: <20220309162337.136773-3-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220309162337.136773-1-sashal@kernel.org> References: <20220309162337.136773-1-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 45b86933c6ea..390b86ec6538 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-puma.dtsi @@ -467,6 +467,12 @@ 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