From patchwork Mon Jun 3 18:37:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 10973817 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A60DC76 for ; Mon, 3 Jun 2019 18:38:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 96A6C2858E for ; Mon, 3 Jun 2019 18:38:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 893D42873C; Mon, 3 Jun 2019 18:38:03 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI 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 EF00E2858E for ; Mon, 3 Jun 2019 18:38:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727120AbfFCSiB (ORCPT ); Mon, 3 Jun 2019 14:38:01 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:38477 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727038AbfFCSiA (ORCPT ); Mon, 3 Jun 2019 14:38:00 -0400 Received: by mail-pf1-f196.google.com with SMTP id a186so10401042pfa.5 for ; Mon, 03 Jun 2019 11:37:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CP6DRWA7LKCgGt9pwiCqtsnPv5tj+Sj41JO+48UE05Q=; b=j00Ayn3UyliSLQr2AD8QNJTrR+U1e6/G8QiuCYi3k/L0XGeh2RofuwkJB3FGkMGzzA Z1Xgqnrv/nbYZwss6HbQTGCwiXu1AsK8LXEf9ZkvQ6O13UFzooy1BBnawo61VBWR7DxD 7VosDUdo4cA25EGkQ/BREI7rV6U3ncfZIk2lw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CP6DRWA7LKCgGt9pwiCqtsnPv5tj+Sj41JO+48UE05Q=; b=ljT68U937Y2MgbWYESWdaHSd1st0jDxaknvQd7dLNJoq66v22lqZPGajHt+05o2XqD dpySxJ8lWD6UMWgFwTLli8eiU+elTj76aQ1IaApyAA7Bb+7isTkEJKeIFqxNdkVhL19B 9Evcz9Ppcp+6NxWNA7HRcAM7wKoR2+RN7dxkNGpOsLxLry1ekOASUV3krHzH+Z1LfFDZ shjX2FPOd+z+Raa89HrYz/iTir6rXtOE4AwO5GSwBKbI4Ym4/rhtmH49hca9UmOYTBSS YP1NqZFejct3JPLqdAIZwJjZcUMkp2xTe0AjvkqR9ZkFBMsmfyEr2TaoHDPWI1YYOP8C rf6w== X-Gm-Message-State: APjAAAXl1ahtWvbxznAvGcJGTR4Hzo3yucGL88q8Uc7G6zGMWU1CgaUQ VDHJ6TB5k/hapPImEiS2aZB5yg== X-Google-Smtp-Source: APXvYqwD8m+vFRG34kPaBeZVgclg3iOa2W61FtinNS3BojeHrk5fIHMmAA6IBO39kL8FIx182NdKuQ== X-Received: by 2002:a17:90a:342:: with SMTP id 2mr31042454pjf.128.1559587079247; Mon, 03 Jun 2019 11:37:59 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id t2sm14808969pfh.166.2019.06.03.11.37.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 03 Jun 2019 11:37:58 -0700 (PDT) From: Douglas Anderson To: Ulf Hansson , Kalle Valo , Adrian Hunter , Arend van Spriel Cc: brcm80211-dev-list.pdl@broadcom.com, linux-rockchip@lists.infradead.org, Double Lo , briannorris@chromium.org, linux-wireless@vger.kernel.org, Naveen Gupta , Madhan Mohan R , mka@chromium.org, Wright Feng , Chi-Hsien Lin , netdev@vger.kernel.org, brcm80211-dev-list@cypress.com, Douglas Anderson , linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Shawn Lin , Wolfram Sang , Avri Altman Subject: [PATCH v2 2/3] mmc: core: API for temporarily disabling auto-retuning due to errors Date: Mon, 3 Jun 2019 11:37:39 -0700 Message-Id: <20190603183740.239031-3-dianders@chromium.org> X-Mailer: git-send-email 2.22.0.rc1.311.g5d7573a151-goog In-Reply-To: <20190603183740.239031-1-dianders@chromium.org> References: <20190603183740.239031-1-dianders@chromium.org> MIME-Version: 1.0 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 Normally when the MMC core sees an "-EILSEQ" error returned by a host controller then it will trigger a retuning of the card. This is generally a good idea. However, if a command is expected to sometimes cause transfer errors then these transfer errors shouldn't cause a re-tuning. This re-tuning will be a needless waste of time. One example case where a transfer is expected to cause errors is when transitioning between idle (sometimes referred to as "sleep" in Broadcom code) and active state on certain Broadcom WiFi cards. Specifically if the card was already transitioning between states when the command was sent it could cause an error on the SDIO bus. Let's add an API that the SDIO card drivers can call that will temporarily disable the auto-tuning functionality. Then we can add a call to this in the Broadcom WiFi driver and any other driver that might have similar needs. NOTE: this makes the assumption that the card is already tuned well enough that it's OK to disable the auto-retuning during one of these error-prone situations. Presumably the driver code performing the error-prone transfer knows how to recover / retry from errors. ...and after we can get back to a state where transfers are no longer error-prone then we can enable the auto-retuning again. If we truly find ourselves in a case where the card needs to be retuned sometimes to handle one of these error-prone transfers then we can always try a few transfers first without auto-retuning and then re-try with auto-retuning if the first few fail. Without this change on rk3288-veyron-minnie I periodically see this in the logs of a machine just sitting there idle: dwmmc_rockchip ff0d0000.dwmmc: Successfully tuned phase to XYZ Fixes: bd11e8bd03ca ("mmc: core: Flag re-tuning is needed on CRC errors") Signed-off-by: Douglas Anderson --- Note that are are a whole boatload of different ways that we could provide an API for the Broadcom WiFi SDIO driver. This patch illustrates one way but if maintainers feel strongly that this is too ugly and have a better idea then I can give it a shot too. From a purist point of view I kinda felt that the "expect errors" really belonged as part of the mmc_request structure, but getting it into there meant changing a whole pile of core SD/MMC APIs. Simply adding it to the host seemed to match the current style better and was a less intrusive change. Changes in v2: - Updated commit message to clarify based on discussion of v1. drivers/mmc/core/core.c | 27 +++++++++++++++++++++++++-- include/linux/mmc/core.h | 2 ++ include/linux/mmc/host.h | 1 + 3 files changed, 28 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 6db36dc870b5..ba4f71aa8cd9 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -144,8 +144,9 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq) int err = cmd->error; /* Flag re-tuning needed on CRC errors */ - if ((cmd->opcode != MMC_SEND_TUNING_BLOCK && - cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200) && + if (cmd->opcode != MMC_SEND_TUNING_BLOCK && + cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200 && + !host->expect_errors && (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) || (mrq->data && mrq->data->error == -EILSEQ) || (mrq->stop && mrq->stop->error == -EILSEQ))) @@ -2163,6 +2164,28 @@ int mmc_sw_reset(struct mmc_host *host) } EXPORT_SYMBOL(mmc_sw_reset); +void mmc_expect_errors_begin(struct mmc_host *host) +{ + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + WARN_ON(host->expect_errors); + host->expect_errors = true; + spin_unlock_irqrestore(&host->lock, flags); +} +EXPORT_SYMBOL_GPL(mmc_expect_errors_begin); + +void mmc_expect_errors_end(struct mmc_host *host) +{ + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + WARN_ON(!host->expect_errors); + host->expect_errors = false; + spin_unlock_irqrestore(&host->lock, flags); +} +EXPORT_SYMBOL_GPL(mmc_expect_errors_end); + static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq) { host->f_init = freq; diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h index 134a6483347a..02a13abf0cda 100644 --- a/include/linux/mmc/core.h +++ b/include/linux/mmc/core.h @@ -178,6 +178,8 @@ int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd, int mmc_hw_reset(struct mmc_host *host); int mmc_sw_reset(struct mmc_host *host); +void mmc_expect_errors_begin(struct mmc_host *host); +void mmc_expect_errors_end(struct mmc_host *host); void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card); #endif /* LINUX_MMC_CORE_H */ diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 43d0f0c496f6..8d553fb8c834 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -398,6 +398,7 @@ struct mmc_host { unsigned int retune_now:1; /* do re-tuning at next req */ unsigned int retune_paused:1; /* re-tuning is temporarily disabled */ unsigned int use_blk_mq:1; /* use blk-mq */ + unsigned int expect_errors:1; /* don't trigger retune upon errors */ int rescan_disable; /* disable card detection */ int rescan_entered; /* used with nonremovable devices */