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 D5198C4167D for ; Wed, 9 Mar 2022 16:23:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235649AbiCIQY3 (ORCPT ); Wed, 9 Mar 2022 11:24:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237978AbiCIQVM (ORCPT ); Wed, 9 Mar 2022 11:21:12 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E9C4B71; Wed, 9 Mar 2022 08:17:43 -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 EE6D06195C; Wed, 9 Mar 2022 16:17:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0EC95C340F6; Wed, 9 Mar 2022 16:17:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646842662; bh=YIErJnc75CCefGBPMKlJGtrhLN04w92UXi9qejAIpu0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pf6B4JVnpnugGVZWwwuUhVWlo2GzNx184mv68AU5/MI/vP0qL+eexfE03wz1nebQJ MBO/GB6Vyt/bCvbZtIRVcIPhmCIAkvtHaUs2wgwYb1TdK5EOxavyHdANa+PzH5HOnq 7yZjWpeg5SNZbreTdpIwlXBVOiStBEt1hionBJbpFb+EgJtbFt5RkIIXmhrJ+VYMDN PfPpsolc/DVg5F3jgFihHhOF6aQ/VXVsK0xwth4/mO6X0zW4mg3mGRs6uJzk+cAxQ1 xZfsXSKOQlPaQHHxtf3ILmy/MLU6Km7a8jLv3iKbXcTIhINyEnO220ONxiD16pYk8M SJlXgkPTE7nlA== 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 5.16 05/27] arm64: dts: rockchip: fix rk3399-puma eMMC HS400 signal integrity Date: Wed, 9 Mar 2022 11:16:42 -0500 Message-Id: <20220309161711.135679-5-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220309161711.135679-1-sashal@kernel.org> References: <20220309161711.135679-1-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: 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 @@ usb3_id: usb3-id { }; &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