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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 1AA9BC48BD7 for ; Thu, 27 Jun 2019 11:39:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB32C2086D for ; Thu, 27 Jun 2019 11:39:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726754AbfF0LjI (ORCPT ); Thu, 27 Jun 2019 07:39:08 -0400 Received: from muru.com ([72.249.23.125]:53712 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726375AbfF0LjI (ORCPT ); Thu, 27 Jun 2019 07:39:08 -0400 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 43780805C; Thu, 27 Jun 2019 11:39:30 +0000 (UTC) Date: Thu, 27 Jun 2019 04:39:04 -0700 From: Tony Lindgren To: Faiz Abbas Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-omap@vger.kernel.org, mark.rutland@arm.com, robh+dt@kernel.org, robertcnelson@gmail.com Subject: Re: [PATCH] ARM: dts: am57xx: Disable voltage switching for SD card Message-ID: <20190627113904.GI5447@atomide.com> References: <20190619102454.5097-1-faiz_abbas@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190619102454.5097-1-faiz_abbas@ti.com> User-Agent: Mutt/1.11.4 (2019-03-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Faiz Abbas [190619 03:25]: > 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). Because the beaglebone X15 (rev A,B and C), am57xx-idks and > am57xx-evms 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). > > commit 88a748419b84 ("ARM: dts: am57xx-idk: Remove support for voltage > switching for SD card") did this only for idk boards. Do it for all > affected boards. Thanks applying into fixes. Regards, Tony