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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH autolearn=ham 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 C220FC43219 for ; Thu, 2 May 2019 14:30:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91CF5205F4 for ; Thu, 2 May 2019 14:30:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="hnOQUAPW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726413AbfEBOac (ORCPT ); Thu, 2 May 2019 10:30:32 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:45184 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726282AbfEBOac (ORCPT ); Thu, 2 May 2019 10:30:32 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id x42EUKOo064994; Thu, 2 May 2019 09:30:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1556807420; bh=FJIj/BoQ7RJOLW73Y4u8uBWdtHI8Oi5sBlOJ1Q0rzMA=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=hnOQUAPWScvNqNC8MxaDVCtohyrzJ7UuV38CBtSKnhA2iNkjDNqGipLMwzV4W9JW3 Er4w4BkhlO/TbpCtfTTaX2VAuOGdnAqFr4+lsNXg30PHE94CAXOS92rmCC2ov2t2at 8Lm208sxjKyH7Zj6Yapzv2S8yg3H8dg9R4yjB958= Received: from DLEE115.ent.ti.com (dlee115.ent.ti.com [157.170.170.26]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x42EUKvH082701 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 2 May 2019 09:30:20 -0500 Received: from DLEE107.ent.ti.com (157.170.170.37) by DLEE115.ent.ti.com (157.170.170.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Thu, 2 May 2019 09:30:19 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DLEE107.ent.ti.com (157.170.170.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Thu, 2 May 2019 09:30:19 -0500 Received: from [10.250.139.87] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id x42EUFHb024717; Thu, 2 May 2019 09:30:16 -0500 Subject: Re: [PATCH] ARM: dts: am57xx-idk: Remove support for voltage switching for SD card To: Tony Lindgren , Faiz Abbas CC: , , , , , , , References: <20190502084748.22518-1-faiz_abbas@ti.com> <20190502142016.GO8007@atomide.com> From: Faiz Abbas Message-ID: <50559611-a501-4331-c88b-5d05f6e756e9@ti.com> Date: Thu, 2 May 2019 20:00:14 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190502142016.GO8007@atomide.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Tony, On 02/05/19 7:50 PM, Tony Lindgren wrote: > * Faiz Abbas [190502 01:48]: >> If UHS speed modes are enabled, a compatible SD card switches down to >> 1.8V during enumeration. If after this a software reboot/crash takes >> place and on-chip ROM tries to enumerate the SD card, the difference in >> IO voltages (host @ 3.3V and card @ 1.8V) may end up damaging the card. >> >> The fix for this is to have support for power cycling the card in >> hardware (with a PORz/soft-reset line causing a power cycle of the >> card). Since am571x-, am572x- and am574x-idk don't have this >> capability, disable voltage switching for these boards. >> >> The major effect of this is that the maximum supported speed >> mode is now high speed(50 MHz) down from SDR104(200 MHz). > > This sounds a bit urgent, does it also need a stable tag or is > it safe to apply against any earlier kernels? > This should be good to apply on any previous releases. Thanks, Faiz