From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750908AbdE2INU (ORCPT ); Mon, 29 May 2017 04:13:20 -0400 Received: from mga07.intel.com ([134.134.136.100]:59032 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750837AbdE2INT (ORCPT ); Mon, 29 May 2017 04:13:19 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,413,1491289200"; d="scan'208";a="267601341" Subject: Re: [PATCH 4/4] mmc: sdhci-esdhc-imx: Remove the ENGcm07207 workaround To: =?UTF-8?Q?Beno=c3=aet_Th=c3=a9baudeau?= , linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org References: <1493805925-3644-1-git-send-email-benoit@wsystem.com> <1493805925-3644-4-git-send-email-benoit@wsystem.com> Cc: Ulf Hansson , Fabio Estevam , joancarles , =?UTF-8?Q?Eric_B=c3=a9nard?= , Wolfram Sang From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: Date: Mon, 29 May 2017 11:07:18 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <1493805925-3644-4-git-send-email-benoit@wsystem.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/05/17 13:05, Benoît Thébaudeau wrote: > The SDHCI_QUIRK_NO_MULTIBLOCK quirk was used as a workaround for the > ENGcm07207 erratum. However, it caused excruciatingly slow SD transfers > (300 kB/s on average), and this erratum actually does not imply that > multiple-block transfers are not supported, so this was overkill. > > The suggested workaround for this erratum is to set SYSCTL.RSTA, but the > simple DAT line software reset (which resets the DMA circuit among > others) triggered by sdhci_finish_data() in case of errors seems to be > sufficient. Indeed, generating errors in a controlled manner on i.MX25 > using the FEVT register right in the middle of read data transfers > without this quirk shows that nothing is written to the buffer by the > eSDHC past CMD12, and no extra Auto CMD12 is sent with AC12EN set, so > the data transfers on AHB are properly aborted. For write data > transfers, neither extra data nor extra Auto CMD12 is sent, as expected. > Moreover, after intensive stress tests on i.MX25, removing > SDHCI_QUIRK_NO_MULTIBLOCK seems to be safe. > > Signed-off-by: Benoît Thébaudeau Aside from one comment below... I would expect to see Acks from other sdhci-esdhc-imx users. Nevertheless, for sdhci: Acked-by: Adrian Hunter > --- > drivers/mmc/host/sdhci-esdhc-imx.c | 16 +++------------- > 1 file changed, 3 insertions(+), 13 deletions(-) > > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c > index fa60d13..868a51f 100644 > --- a/drivers/mmc/host/sdhci-esdhc-imx.c > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c > @@ -115,11 +115,6 @@ > */ > #define ESDHC_FLAG_MULTIBLK_NO_INT BIT(1) > /* > - * The flag enables the workaround for ESDHC errata ENGcm07207 which > - * affects i.MX25 and i.MX35. > - */ > -#define ESDHC_FLAG_ENGCM07207 BIT(2) > -/* > * The flag tells that the ESDHC controller is an USDHC block that is > * integrated on the i.MX6 series. > */ > @@ -149,11 +144,11 @@ struct esdhc_soc_data { > }; > > static struct esdhc_soc_data esdhc_imx25_data = { > - .flags = ESDHC_FLAG_ENGCM07207, > + .flags = ESDHC_FLAG_ERR004536, > }; > > static struct esdhc_soc_data esdhc_imx35_data = { > - .flags = ESDHC_FLAG_ENGCM07207, > + .flags = ESDHC_FLAG_ERR004536, > }; > > static struct esdhc_soc_data esdhc_imx51_data = { > @@ -286,7 +281,7 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg) > * ADMA2 capability of esdhc, but this bit is messed up on > * some SOCs (e.g. on MX25, MX35 this bit is set, but they > * don't actually support ADMA2). So set the BROKEN_ADMA > - * uirk on MX25/35 platforms. > + * quirk on MX25/35 platforms. Please do spelling fixes as a separate patch. Note there are several spelling errors in comments in drivers/mmc/host/sdhci-esdhc-imx.c so you could easily do a few of them to make a separate patch more worthwhile. > */ > > if (val & SDHCI_CAN_DO_ADMA1) { > @@ -1278,11 +1273,6 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > if (IS_ERR(imx_data->pins_default)) > dev_warn(mmc_dev(host->mmc), "could not get default state\n"); > > - if (imx_data->socdata->flags & ESDHC_FLAG_ENGCM07207) > - /* Fix errata ENGcm07207 present on i.MX25 and i.MX35 */ > - host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK > - | SDHCI_QUIRK_BROKEN_ADMA; > - > if (esdhc_is_usdhc(imx_data)) { > host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN; > host->mmc->caps |= MMC_CAP_1_8V_DDR; >