From patchwork Thu Jun 28 08:13:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Agner X-Patchwork-Id: 10493271 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 0243A60325 for ; Thu, 28 Jun 2018 08:14:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E299C2A0F7 for ; Thu, 28 Jun 2018 08:14:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D50922A0FD; Thu, 28 Jun 2018 08:14:13 +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 741302A0F7 for ; Thu, 28 Jun 2018 08:14:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934370AbeF1IOL (ORCPT ); Thu, 28 Jun 2018 04:14:11 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:49418 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934470AbeF1INg (ORCPT ); Thu, 28 Jun 2018 04:13:36 -0400 Received: from trochilidae.toradex.int (unknown [46.140.72.82]) by mail.kmu-office.ch (Postfix) with ESMTPSA id 4E0615C0C49; Thu, 28 Jun 2018 10:13:35 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1530173615; 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=AW0AXaKWv0I5JtfJLm0H1BTgUszfU1M/rHZROIKYnb0=; b=qlJoTy/1L8i1FCJGtqEIu0c5FeY3WBKZwEs9r+p/3zFCB/pVTe9U1t4GRSAzQm3gZlc9Jk hQEUWMByStJoew92HCPrn2a01xhwolswgKCx4LeLinxwgVtlX6TIN5CwmyKC5A+gxOcVpR lXqeoakriB9zaoBbaujuCLpRKjnD2mM= From: Stefan Agner To: adrian.hunter@intel.com, ulf.hansson@linaro.org Cc: fabio.estevam@nxp.com, haibo.chen@nxp.com, aisheng.dong@nxp.com, michael@amarulasolutions.com, rmk+kernel@armlinux.org.uk, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Agner Subject: [PATCH 3/3] mmc: sdhci-esdhc-imx: prevent stack from using higher speed modes Date: Thu, 28 Jun 2018 10:13:31 +0200 Message-Id: <20180628081331.13051-4-stefan@agner.ch> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180628081331.13051-1-stefan@agner.ch> References: <20180628081331.13051-1-stefan@agner.ch> X-Spamd-Result: default: False [-2.10 / 15.00]; TO_MATCH_ENVRCPT_ALL(0.00)[]; BAYES_HAM(-3.00)[100.00%]; TAGGED_RCPT(0.00)[kernel]; MIME_GOOD(-0.10)[text/plain]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_SEVEN(0.00)[10]; 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 If pinctrl configurations for higher speed modes are missing, the stack currently uses the no 1.8V quirk. This comes close to what we need but not exactly: E.g. if a eMMC chip uses 1.8V signaling (by specifying a 1.8V only vqmmc-supply) while not providing any 100MHz/200MHz pinctrl configurations then the SDHCI_QUIRK2_NO_1_8_V leads the stack to print signaling voltage switch failed errors continuously: mmc1: Switching to 3.3V signalling voltage failed Presumably because the stack tries to use 3.3V signaling: # cat /sys/kernel/debug/mmc1/ios ... timing spec: 8 (mmc DDR52) signal voltage: 0 (3.30 V) ... With using SDHCI_QUIRK2_NO_UHS_HS200_HS400 we prevent the stack from choosing any modes require speeds higher than 52MHz while still allowing to select modes using 1.8V at lower speeds (e.g. DDR52): # cat /sys/kernel/debug/mmc1/ios ... timing spec: 8 (mmc DDR52) signal voltage: 1 (1.80 V) ... Signed-off-by: Stefan Agner --- drivers/mmc/host/sdhci-esdhc-imx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 20a420b765b3..4a1c33018072 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -1165,10 +1165,10 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev, * fall back to not supporting uhs by specifying no * 1.8v quirk */ - host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V; + host->quirks2 |= SDHCI_QUIRK2_NO_UHS_HS200_HS400; } } else { - host->quirks2 |= SDHCI_QUIRK2_NO_1_8_V; + host->quirks2 |= SDHCI_QUIRK2_NO_UHS_HS200_HS400; } /* call to generic mmc_of_parse to support additional capabilities */