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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,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 38CA3C4741F for ; Thu, 5 Nov 2020 11:26:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D01302078E for ; Thu, 5 Nov 2020 11:26:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730238AbgKEL0I (ORCPT ); Thu, 5 Nov 2020 06:26:08 -0500 Received: from foss.arm.com ([217.140.110.172]:57968 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726715AbgKEL0D (ORCPT ); Thu, 5 Nov 2020 06:26:03 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9A1C7142F; Thu, 5 Nov 2020 03:26:02 -0800 (PST) Received: from [10.57.54.223] (unknown [10.57.54.223]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 221F63F719; Thu, 5 Nov 2020 03:26:00 -0800 (PST) Subject: Re: [PATCH] ARM: dts: exynos: Assign a fixed index to mmc devices on exynos4412 based ODROID boards To: Markus Reichl , Marek Szyprowski , Rob Herring , Kukjin Kim , Krzysztof Kozlowski Cc: devicetree@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20201104102558.11070-1-m.reichl@fivetechno.de> <5800260a-5332-f627-eb36-32df4fbf05e3@fivetechno.de> <71e4ecca-b980-e224-0fbe-b30330e490fb@samsung.com> <2ddf7343-799b-418b-bb00-a926f1030db7@fivetechno.de> From: Robin Murphy Message-ID: Date: Thu, 5 Nov 2020 11:26:00 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <2ddf7343-799b-418b-bb00-a926f1030db7@fivetechno.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-11-05 08:31, Markus Reichl wrote: > Hi Marek, > > on rk3399 the proposed ordering [1] is according to base address in DT. FWIW, note that in RK3399's case the SoC itself provides no logical numbering to follow - the pin groups are named "EMMC", "SDIO0" and "SDMMC0" in the datasheet, while the TRM uses "emmc", "sdio" and "sdmmc" in signal and register names. If the SoC *does* have an inherent notion of numbered interfaces, I would agree that following that numbering is the most logical thing to do. Robin. > > [1] > https://patchwork.kernel.org/patch/11881427 > > Am 04.11.20 um 14:44 schrieb Marek Szyprowski: >> On 04.11.2020 14:13, Marek Szyprowski wrote: >>> On 04.11.2020 14:06, Markus Reichl wrote: >>>> Am 04.11.20 um 13:25 schrieb Marek Szyprowski: >>>>> On 04.11.2020 11:25, Markus Reichl wrote: >>>>>> Recently introduced async probe on mmc devices can shuffle block IDs. >>>>>> Pin them to fixed values to ease booting in evironments where UUIDs >>>>>> ar not practical. >>>>>> Use newly introduced aliases for mmcblk devices from [1]. >>>>>> >>>>>> [1] >>>>>> https://patchwork.kernel.org/patch/11747669/ >>>>>> >>>>>> Signed-off-by: Markus Reichl >>>>>> --- >>>>>>    arch/arm/boot/dts/exynos4412-odroid-common.dtsi | 5 +++++ >>>>>>    1 file changed, 5 insertions(+) >>>>>> >>>>>> diff --git a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi >>>>>> b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi >>>>>> index a5c1ce1e396c..aa10d5bc7e1c 100644 >>>>>> --- a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi >>>>>> +++ b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi >>>>>> @@ -13,6 +13,11 @@ >>>>>>    #include "exynos-mfc-reserved-memory.dtsi" >>>>>>      / { >>>>>> +    aliases { >>>>>> +        mmc0 = &sdhci_2; >>>>>> +        mmc1 = &mshc_0; >>>>> Like in the OdroidXU3-family patch, I would use 0 for the eMMC >>>>> (mshc_0) >>>>> and 2 for the SD-card (sdhci_2). >>>> How to deal then with sdhci_0 (from exynos4.dtsi) vc. mshc_0 (from >>>> exynos4412.dts)? >>> sdhci_0 and mshc_0 both operate on the same physical MMC0 bus, so this >>> is not an issue. They cannot be used simultaneously. The latter is just >>> faster, the first one has been left there mainly for the software >>> compatibility. >> >> I've thought a bit more on this and I would simply prefer to add generic >> MMC aliases to the top-level Exynos dtsi files (3250, 4210, 4412, 5250, >> 5410, 5420) to keep Linux logical MMC bus numbers in sync with the HW >> bus numbers on all boards. >> >> Best regards >> > > Gruß, > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >