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=-9.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 87CC2C433E0 for ; Mon, 15 Feb 2021 00:32:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 50A9F64D5D for ; Mon, 15 Feb 2021 00:32:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229969AbhBOAcg (ORCPT ); Sun, 14 Feb 2021 19:32:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229818AbhBOAcg (ORCPT ); Sun, 14 Feb 2021 19:32:36 -0500 Received: from mail-ed1-x52f.google.com (mail-ed1-x52f.google.com [IPv6:2a00:1450:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B27F7C061574 for ; Sun, 14 Feb 2021 16:31:55 -0800 (PST) Received: by mail-ed1-x52f.google.com with SMTP id y10so1368183edt.12 for ; Sun, 14 Feb 2021 16:31:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=EPnN7V+TXLymh4O0EgyFMT7UejwMzeaWKlMB31n3+0w=; b=JLIdCsZFPZCPR5mAH2lmpvUvo4Pf7BA7MHfoXepsF06J2WRg8WD56u0WVYbLvSXd3Q 0rzlxoSAJqbHY0h3psHOUt5o54gSDcTiAqdNNrX5HiMp6xvwymYf9VDcMJvawKLLhkq7 obhEBhlduXweDUfoEkMOmPkRbssiZDGqFIxVn8VwXns7QoT5mJBNXGM+M4VYBYiSOWnc S3y5QDSJEhMXnPl5JlepWSnjdTbdgR6q4tjiT6nCiOlr58Sm2tu0dfKWYKYXMv/dmPgK xTKHF0hWm1zvKt1/IXuZyMGNqeFLKpnFPzYaup+xaS1nQIgG1Obvw8HH2573VIo8v9gJ RdCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=EPnN7V+TXLymh4O0EgyFMT7UejwMzeaWKlMB31n3+0w=; b=TR0RBRUCFsukZLG2VUY6tIFfkrQrvnvpL+QMgW2+hZzXLsW5dLa82cs/9a/J11LQU0 L1vkgpQtmJ7x/spR9tR3+KRXySeXMr6WwA+cOJwL5y65D104mDAJKXKVZ4Xf8Oo44VaD 211K9pt/LzPRCHnvSeyAkj/U1LfVGe4G2FHcKMlPyPYWeZkilNpRSrAw7s9J3BdGCy45 /C22+8OFfYbOAhD2TuEOFntQYGJ59w6J/Eraewfzo84ZyHZSqJWcd2AWdEQODP3r3tCK 5J/cvSND3lD3/013TFZ1sBEoKOtIaB7SwyO2KUa6Ejb2TUmOmH22cpKlV7J9ZiZ1niYl 251A== X-Gm-Message-State: AOAM531r6qK4ETeW6JV0QGdCDvEm+Z2kw7L955rCtKQR94/jvk+ZRRcB K+hGzrnWHOQ6VzhxyETDcoCkI9yxVSo= X-Google-Smtp-Source: ABdhPJys8NrVjCv6rVJJikFneYev22ro2hHAiJNV+kjuj2kply/kPcifRfZaHalCdE/YSwba+Q8BJg== X-Received: by 2002:a05:6402:1215:: with SMTP id c21mr13281236edw.310.1613349114329; Sun, 14 Feb 2021 16:31:54 -0800 (PST) Received: from lupo-laptop (host-79-32-153-26.retail.telecomitalia.it. [79.32.153.26]) by smtp.gmail.com with ESMTPSA id m24sm9645136eji.10.2021.02.14.16.31.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 Feb 2021 16:31:54 -0800 (PST) From: Luca Porzio X-Google-Original-From: Luca Porzio Date: Mon, 15 Feb 2021 01:31:52 +0100 To: linux-mmc@vger.kernel.org Cc: Zhan Liu , Luca Porzio Subject: [RFC PATCH 0/2] Support temporarily disable of the CMDQ mode Message-ID: <20210215003150.GA12202@lupo-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org eMMC protocol was born as single threaded and many use cases still expect single thread operation mode. Through time the Command Queue was developed and supported but many legacy operation are still performed using single thread mode. An example is FFU operation performed by using mmc-utils which is currently broken for devices supporting CMDQ mode. In order to enable legacy command sequences, we make cmdq_en sysfs parameter writeable: setting this parameter to zero will temporarily disable CMDQ mode and let legacy command sequence be supported. Setting the cmdq_en parameter to one, will enable CMDQ mode back on. Luca Porzio (2): Remove unnecessary usage of use_cqe parameter in mmc_queue and use more appropriate mmc_host->cqe_enabled Make cmdq_en attribute in sysfs, writeable. When 0 is written: - CMDQ is disabled and kept disabled across device reboots. When 1 is written: - CMDQ mode is instantly reneabled (if supported). drivers/mmc/core/block.c | 7 +- drivers/mmc/core/mmc.c | 152 ++++++++++++++++++++++++++++++--------- drivers/mmc/core/queue.c | 11 ++- drivers/mmc/core/queue.h | 1 - include/linux/mmc/card.h | 1 + 5 files changed, 127 insertions(+), 45 deletions(-) -- 2.17.1