From patchwork Thu Jul 12 07:39:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Agner X-Patchwork-Id: 10521147 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 39419601C2 for ; Thu, 12 Jul 2018 07:40:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ECB0F293C5 for ; Thu, 12 Jul 2018 07:40:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DF36729435; Thu, 12 Jul 2018 07:40:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 833B2293C5 for ; Thu, 12 Jul 2018 07:40:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726946AbeGLHsT (ORCPT ); Thu, 12 Jul 2018 03:48:19 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:55534 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726474AbeGLHsT (ORCPT ); Thu, 12 Jul 2018 03:48:19 -0400 Received: from trochilidae.toradex.int (unknown [46.140.72.82]) by mail.kmu-office.ch (Postfix) with ESMTPSA id 58FCA5C21AE; Thu, 12 Jul 2018 09:39:30 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1531381174; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4wyMXkujJgN3jQUwl1mNOxOpAFMCFVzLo77q8H9i9DQ=; b=w01CBHkjCi6pKosB68LsEKDwUpG+XOXVToGZL0CynyNCMmdTba9lEsE5cGbjfqGOafcSXD Je6lBFGsjCmq4JRZBhiFHcB1qyaLnLYcM2wmYNGGvEb6Mpw0arp1VvxVpuLfnypuF/arWj R9t6lRZkWsg/rA0u9HKj/Iik3XxjZTk= From: Stefan Agner To: adrian.hunter@intel.com, ulf.hansson@linaro.org Cc: thierry.reding@gmail.com, jonathanh@nvidia.com, marcel.ziswiler@toradex.com, linux-mmc@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Agner Subject: [PATCH 3/3] mmc: tegra: prevent ACMD23 on Tegra 3 Date: Thu, 12 Jul 2018 09:39:04 +0200 Message-Id: <20180712073904.4705-3-stefan@agner.ch> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180712073904.4705-1-stefan@agner.ch> References: <20180712073904.4705-1-stefan@agner.ch> X-Spamd-Result: default: False [-0.75 / 15.00]; TO_MATCH_ENVRCPT_ALL(0.00)[]; BAYES_HAM(-1.65)[92.83%]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.10)[text/plain]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_SEVEN(0.00)[9]; FROM_EQ_ENVFROM(0.00)[]; DKIM_SIGNED(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_COUNT_ZERO(0.00)[0]; MID_CONTAINS_FROM(1.00)[]; ASN(0.00)[asn:6830, ipnet:46.140.0.0/17, country:AT]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[] Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP It seems that SD3.0 advertisement needs to be set for higher eMMC speed modes (namely DDR52) as well. The TRM states that the SD3.0 advertisement bit should be set for all controller instances, even for those not supporting UHS-I mode... When specifying vqmmc-supply as a fixed 1.8V regulator on a Tegra SD/MMC instance which is connected to a eMMC device, the stack enables SD3.0. However, enabling it has consequences: If SDHCI 3.0 support is advertised the stack enables Auto-CMD23. Unfortunately Auto-CMD23 seems not to work well with Tegra 3 currently. It leads to regular warnings: mmc2: Got command interrupt 0x00010000 even though no command operation was in progress. It is not entirely clear why those errors happens. It seems that a Linux 3.1 based downstream kernel which has Auto-CMD23 support does not show those warnings. Use quirk SDHCI_QUIRK2_ACMD23_BROKEN to prevent Auto-CMD23 being used for now. With this the eMMC works stable on high-speed mode while still announcing SD3.0. This allows to use mmc-ddr-1_8v to enables DDR52 mode. In DDR52 mode read speed improves from about 42MiB/s to 72MiB/s on an Apalis T30. Signed-off-by: Stefan Agner --- drivers/mmc/host/sdhci-tegra.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c index 888a1ad511db..11c0b2069c7c 100644 --- a/drivers/mmc/host/sdhci-tegra.c +++ b/drivers/mmc/host/sdhci-tegra.c @@ -336,7 +336,15 @@ static const struct sdhci_pltfm_data sdhci_tegra30_pdata = { SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC | SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN, .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN | - SDHCI_QUIRK2_BROKEN_HS200, + SDHCI_QUIRK2_BROKEN_HS200 | + /* + * Auto-CMD23 leads to "Got command interrupt 0x00010000 even + * though no command operation was in progress." + * + * The exact reason is unknown, as the same hardware seems + * to support Auto CMD23 on a downstream 3.1 kernel. + */ + SDHCI_QUIRK2_ACMD23_BROKEN, .ops = &tegra_sdhci_ops, };