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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10CC1C433B4 for ; Tue, 11 May 2021 15:50:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D67DF61278 for ; Tue, 11 May 2021 15:50:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231980AbhEKPvb (ORCPT ); Tue, 11 May 2021 11:51:31 -0400 Received: from lizzard.sbs.de ([194.138.37.39]:53758 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231561AbhEKPv2 (ORCPT ); Tue, 11 May 2021 11:51:28 -0400 Received: from mail2.sbs.de (mail2.sbs.de [192.129.41.66]) by lizzard.sbs.de (8.15.2/8.15.2) with ESMTPS id 14BFnqIE012506 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 11 May 2021 17:49:52 +0200 Received: from [167.87.32.54] ([167.87.32.54]) by mail2.sbs.de (8.15.2/8.15.2) with ESMTP id 14BFQqmi012261; Tue, 11 May 2021 17:26:52 +0200 Subject: Re: [PATCH v2] arm64: dts: ti: k3-am65: Add support for UHS-I modes in MMCSD1 subsystem To: Aswath Govindraju Cc: Vignesh Raghavendra , Lokesh Vutla , Kishon Vijay Abraham I , Nishanth Menon , Tero Kristo , Rob Herring , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210511095339.16268-1-a-govindraju@ti.com> <200b5648-b2d9-b4c9-f81a-b39c3baf81f9@siemens.com> <7561137c-adf1-bf03-c442-ff8174b2f143@ti.com> From: Jan Kiszka Message-ID: <95539fea-8190-7a3d-05aa-90824eb03293@siemens.com> Date: Tue, 11 May 2021 17:26:52 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: <7561137c-adf1-bf03-c442-ff8174b2f143@ti.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11.05.21 12:13, Aswath Govindraju wrote: > Hi Jan, > > On 11/05/21 3:31 pm, Jan Kiszka wrote: >> On 11.05.21 11:53, Aswath Govindraju wrote: >>> UHS-I speed modes are supported in AM65 S.R. 2.0 SoC[1]. >>> >>> Add support by removing the no-1-8-v tag and including the voltage >>> regulator device tree nodes for power cycling. >>> >>> However, the 4 bit interface of AM65 SR 1.0 cannot be supported at 3.3 V or >>> 1.8 V because of erratas i2025 and i2026 [2]. As the SD card is the primary >>> boot mode for development usecases, continue to enable SD card and disable >>> UHS-I modes in it to minimize any ageing issues happening because of >>> erratas. >>> >>> k3-am6528-iot2050-basic and k3-am6548-iot2050-advanced boards use S.R. 1.0 >>> version of AM65 SoC. Therefore, add no-1-8-v in sdhci1 device tree nodes >>> for these boards. >>> >>> [1] - https://www.ti.com/lit/ug/spruid7e/spruid7e.pdf >>> [2] - https://www.ti.com/lit/er/sprz452e/sprz452e.pdf >>> >>> Signed-off-by: Aswath Govindraju >>> --- >>> arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 1 - >>> .../boot/dts/ti/k3-am6528-iot2050-basic.dts | 4 +++ >>> .../arm64/boot/dts/ti/k3-am654-base-board.dts | 33 +++++++++++++++++++ >>> .../dts/ti/k3-am6548-iot2050-advanced.dts | 4 +++ >>> 4 files changed, 41 insertions(+), 1 deletion(-) >>> >>> diff --git a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi >>> index cb340d1b401f..632f32fce4a1 100644 >>> --- a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi >>> +++ b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi >>> @@ -301,7 +301,6 @@ >>> ti,otap-del-sel = <0x2>; >>> ti,trm-icp = <0x8>; >>> dma-coherent; >>> - no-1-8-v; >>> }; >>> >>> scm_conf: scm-conf@100000 { >>> diff --git a/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts b/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts >>> index 4f7e3f2a6265..485266960d5f 100644 >>> --- a/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts >>> +++ b/arch/arm64/boot/dts/ti/k3-am6528-iot2050-basic.dts >>> @@ -40,6 +40,10 @@ >>> status = "disabled"; >>> }; >>> >>> +&sdhci1 { >>> + no-1-8-v; >>> +}; >>> + >> >> Let's move that to k3-am65-iot2050-common.dtsi, to avoid repeating >> yourself. There is already a sdhci1 extension. >> > > The reason why I added these tags in board dts and not in the common > dtsi is because if it was added in the common board then for all the iot > boards this will be applicable and in future if a different version of > iot boards use S.R. 2.0 then we might have to change it again. Yes, we will have to take care of the split-up for SR2.0-based variants. I didn't have the chance study their DTs yet but I strongly suspect that there will be more differences. Then we may add some k3-am65-iot2050-common-{SR1,SR2}.dtsi. So, I would not try to refactor when not all variables are on the table yet. Thanks Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux