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=-9.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 56243C433DF for ; Fri, 17 Jul 2020 10:18:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 24D5520775 for ; Fri, 17 Jul 2020 10:18:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="yu/iJ+SZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726000AbgGQKSf (ORCPT ); Fri, 17 Jul 2020 06:18:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725912AbgGQKSe (ORCPT ); Fri, 17 Jul 2020 06:18:34 -0400 Received: from mail-ua1-x944.google.com (mail-ua1-x944.google.com [IPv6:2607:f8b0:4864:20::944]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A7EEC061755 for ; Fri, 17 Jul 2020 03:18:34 -0700 (PDT) Received: by mail-ua1-x944.google.com with SMTP id k7so2694893uan.13 for ; Fri, 17 Jul 2020 03:18:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=hvtn7S8MwZBmKINZxbgnjO3QCsAWEXypLj1fRvDH5kg=; b=yu/iJ+SZpWU9eQWKAR/BYjHqHPTQiZon3e1MYaJiGQOy8cic39hJaTBl2rKhcpZ7Bn yJnEhDwtRuiJSKAbTtSIc9jOlOsDgzv3PlC0S0OXMNz/tyO7ULClbCygZVWu51wWfH9f I4q7Y3kJenM8Rs+crY5Afb8WU6B9D+i1KTC+KCLn3dBo00kaMbbbMqIUh5Q4UXAiVeEP 3In/71MMe0wtAvUo2mxotrT4H8Aqa6G4JsK83G1u1nxhVJqKckgOfDHrnJulXZ7cRxmU NiWoyiA2Q6Q72Pm/uVAZT822dbVe2h6RmBYPes1V2NsOWjoeR1nbf3KIvgKbywrqyhMz 22Mg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=hvtn7S8MwZBmKINZxbgnjO3QCsAWEXypLj1fRvDH5kg=; b=KyRO1I7TuVUmUI1QWhaxI1BWzSLn6pdlOE7nh9iP8hzXjZYoRyvNSUuvntqJaNiGI0 9AT45Kx4YEwEKAp8Q4hC0Xtp0/paQ7yKbjiW0QC1MsBvFhjbjJHZlSOvWjz6azBMcVsw j8MIxLN1lfNagpzTN3KBQ2etu/e/tPwpPHOBMfIom/gokAsjn4hEK1lRQX1Om/8n4Xra U7dOOemRqS5ERnNvsT1Q9+RmmVkn6IbgzhCoY+Y35NA02rjcs1jIlW0fMABbPQvKgWpU 1DNQ54JqMnhzohYdzZUQEMFT7qUbq9AUzZhkDNBLC/zwpVJZnOkjXOnlI/PYhy5wu14M OQDg== X-Gm-Message-State: AOAM53103pme7VZyddtFO6j5rRPw92st3gAQecG0WybirrrGqEZU75FN 0P+67fwq//cq54lp/pClkU5klk12N2EfytaO9K2IBQ== X-Google-Smtp-Source: ABdhPJwjl5wbOPP7k7Rj3mCW95qbauo8zWHhkn9D5kbVziMQqXuzRmbUrA6beG6a06cPTqiyItfNgHfbKBiAXE9bWMk= X-Received: by 2002:ab0:6049:: with SMTP id o9mr6643361ual.19.1594981113408; Fri, 17 Jul 2020 03:18:33 -0700 (PDT) MIME-Version: 1.0 References: <20200710110752.28853-1-benchuanggli@gmail.com> In-Reply-To: <20200710110752.28853-1-benchuanggli@gmail.com> From: Ulf Hansson Date: Fri, 17 Jul 2020 12:17:57 +0200 Message-ID: Subject: Re: [RFC PATCH V3 00/21] Add support UHS-II for GL9755 To: Ben Chuang Cc: Adrian Hunter , "linux-mmc@vger.kernel.org" , Linux Kernel Mailing List , Ben Chuang , Takahiro Akashi , greg.tu@genesyslogic.com.tw Content-Type: text/plain; charset="UTF-8" Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org On Fri, 10 Jul 2020 at 13:07, Ben Chuang wrote: > > Summary > ======= > These patches[1] support UHS-II and fix GL9755 UHS-II compatibility. First of all, thanks for posting this - and my apologies for not having the bandwidth to review the earlier versions. > > About UHS-II, roughly deal with the following three parts: > 1) A UHS-II detection and initialization: > - Host setup to support UHS-II (Section 3.13.1 Host Controller Setup Sequence > [2]). > - Detect a UHS-II I/F (Section 3.13.2 Card Interface Detection Sequence[2]). > - In step(9) of Section 3.13.2 in [2], UHS-II initialization is include Section > 3.13.3 UHS-II Card Initialization and Section 3.13.4 UHS-II Setting Register > Setup Sequence. > > 2) Send Legacy SD command through SD-TRAN > - Encapsulated SD packets are defined in SD-TRAN in order to ensure Legacy SD > compatibility and preserve Legacy SD infrastructures (Section 7.1.1 Packet > Types and Format Overview[3]). > - Host issue a UHS-II CCMD packet or a UHS-II DCMD (Section 3.13.5 UHS-II > CCMD Packet issuing and Section 3.13.6 UHS-II DCMD Packet issuing[2]). > > 3) UHS-II Interrupt > - Except for UHS-II error interrupts, most interrupts share the original > interrupt registers. The above points to some specifications, which is good, but what I really need to be able to do a proper review - is an explanation of *what*, *why* and *how* the series implements the UHS-II support. To be clear, I don't need in-depth details, as that should be described in each patch's commit message, but I would appreciate an overall description of the approach you have taken to implement this. The reason I need this is because UHS-II is a completely new interface/protocol. If it wasn't because that a UHS-II card is also required to be backwards compatible with the legacy SD interface, one could even consider introducing an entirely new subsystem. Not saying that we should, but just pointing out that the series is not trivial to review. That said, I am going to give it a real try to do the review. I will try to focus on the overall approach, rather than on the details, at least to start with. > > Patch structure > =============== > patch#1-#7: for core > patch#8-#17: for sdhci > patch#18-#21: for GL9755 > > Tests > ===== > Ran 'dd' command to evaluate the performance: > (SanDisk UHS-II card on GL9755 controller) > Read Write > UHS-II disabled (UHS-I): 88.3MB/s 60.7MB/s > UHS-II enabled : 206MB/s 80MB/s I like these comparisons, thanks for sharing! What UHS-II interface mode does you HW support? FD156, HD312, FD312 FD624? > > TODO > ==== > - replace some define with BIT macro > > Reference > ========= > [1] https://gitlab.com/ben.chuang/linux-uhs2-gl9755.git > [2] SD Host Controller Simplified Specification 4.20 > [3] UHS-II Simplified Addendum 1.02 > > Changes in v3 (Jul. 10, 2020) > * rebased to v5.8-rc4 > * add copyright notice > * reorganize the patch set and split some commits into smaller ones > * separate uhs-2 headers from others > * correct wrong spellings > * fix most of checkpatch warnings/errors > * remove all k[cz]alloc() from the code > * guard sdhci-uhs2 specific code with > 'if (IS_ENABLED(CONFIG_MMC_SDHCI_UHS2))' > * make sdhci-uhs2.c as a module > * trivial changes, including > - rename back sdhci-core.c to sdhci.c > - allow vendor code to disable uhs2 if v4_mode == 0 > in __sdhci_add_host() > - merge uhs2_power_up() into mmc_power_up() > - remove flag_uhs2 from mmc_attach_sd() > - add function descriptions to EXPORT'ed functions > - other minor code optimization > > Changes in v2 (Jan. 9, 2020) > * rebased to v5.5-rc5 > > AKASHI Takahiro (15): > mmc: core: UHS-II support, modify power-up sequence > mmc: core: UHS-II support, skip set_chip_select() > mmc: core: UHS-II support, skip TMODE setup in some cases > mmc: core: UHS-II support, generate UHS-II SD command packet > mmc: core: UHS-II support, set APP_CMD bit if necessary > mmc: sdhci: add a kernel configuration for enabling UHS-II support > mmc: sdhci: add UHS-II related definitions in headers > mmc: sdhci: UHS-II support, dump UHS-II registers > mmc: sdhci: UHS-II support, export host operations to core > mmc: sdhci: UHS-II support, skip signal_voltage_switch() > mmc: sdhci: UHS-II support, handle vdd2 in case of power-off > mmc: sdhci: UHS-II support, modify set_power() to handle vdd2 > mmc: sdhci: UHS-II support, export helper functions to a module > mmc: sdhci: UHS-II support, implement operations as a module > mmc: core: add post-mmc_attach_sd hook > > Ben Chuang (6): > mmc: add UHS-II related definitions in public headers > mmc: core: UHS-II support, try to select UHS-II interface > mmc: sdhci: UHS-II support, add hooks for additional operations > mmc: sdhci-uhs2: add pre-detect_init hook > mmc: sdhci-uhs2: add post-mmc_attach_sd hook > mmc: sdhci-pci-gli: enable UHS-II mode for GL9755 > > drivers/mmc/core/Makefile | 2 +- > drivers/mmc/core/block.c | 7 +- > drivers/mmc/core/bus.c | 5 +- > drivers/mmc/core/core.c | 119 +++- > drivers/mmc/core/regulator.c | 14 + > drivers/mmc/core/sd.c | 32 ++ > drivers/mmc/core/sd_ops.c | 12 + > drivers/mmc/core/uhs2.c | 874 ++++++++++++++++++++++++++++++ Nitpick: I would prefer to prefix any new needed file with sd_*. In this case, sd_uhs2.c|h. > drivers/mmc/core/uhs2.h | 21 + > drivers/mmc/host/Kconfig | 10 + > drivers/mmc/host/Makefile | 1 + > drivers/mmc/host/sdhci-omap.c | 2 +- > drivers/mmc/host/sdhci-pci-core.c | 4 +- > drivers/mmc/host/sdhci-pci-gli.c | 361 +++++++++++- > drivers/mmc/host/sdhci-pxav3.c | 4 +- > drivers/mmc/host/sdhci-uhs2.c | 797 +++++++++++++++++++++++++++ > drivers/mmc/host/sdhci-uhs2.h | 215 ++++++++ > drivers/mmc/host/sdhci-xenon.c | 4 +- > drivers/mmc/host/sdhci.c | 321 +++++++++-- > drivers/mmc/host/sdhci.h | 113 +++- > include/linux/mmc/card.h | 1 + > include/linux/mmc/core.h | 6 + > include/linux/mmc/host.h | 31 ++ > include/linux/mmc/uhs2.h | 268 +++++++++ > 24 files changed, 3151 insertions(+), 73 deletions(-) > create mode 100644 drivers/mmc/core/uhs2.c > create mode 100644 drivers/mmc/core/uhs2.h > create mode 100644 drivers/mmc/host/sdhci-uhs2.c > create mode 100644 drivers/mmc/host/sdhci-uhs2.h > create mode 100644 include/linux/mmc/uhs2.h > > -- > 2.27.0 > Kind regards Uffe