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=-8.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 EA275C433DF for ; Wed, 27 May 2020 07:46:13 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BC91B207CB for ; Wed, 27 May 2020 07:46:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="nUtHw/NI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BC91B207CB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=rZJUHTf5wwi/QaTBlKcOJnGzZh2VCpqjBNenTHFLUgw=; b=nUtHw/NICFcqjI scqIgBu9gCRx3oMzxLgYXMnEMi9jcgGd98FEKuVRtKs1trF069Sog+mLdOtUhk2X2jRpmeX2e4q3q pNJHXNVuLJzN/iRBcEWCzuFSVK7pjqveblQfSaf9x6/pk055Q5kWT7m27EFpg9LP4MVA0LfL604vN TuLKGcAiz2Re+wcukb8Nom6U3Bq8d0cbJmvy4A1csHZoMwHEK0YayMtteo+EOO8AzUzy6SgL8MlC5 B7nwLwipcOSHSc8UsYA6lMDYYnqE9fEiVZ9Gf8ctK2mxsoyOXgSaGf/C2YwC2RmwgEc0WijiGN1iT HqPESLVYnsDocB6aVe1A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jdqlG-0002FN-E9; Wed, 27 May 2020 07:46:02 +0000 Received: from relay6-d.mail.gandi.net ([217.70.183.198]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jdqlD-0002Ex-BG for linux-mtd@lists.infradead.org; Wed, 27 May 2020 07:46:01 +0000 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id E7B98C0015; Wed, 27 May 2020 07:45:53 +0000 (UTC) Date: Wed, 27 May 2020 09:45:51 +0200 From: Miquel Raynal To: Boris Brezillon Subject: Re: [PATCH v5 21/28] mtd: rawnand: Introduce nand_choose_best_sdr_timings() Message-ID: <20200527094551.59a72f2f@xps13> In-Reply-To: <20200526235003.5bb0ba91@collabora.com> References: <20200526191725.7591-1-miquel.raynal@bootlin.com> <20200526191725.7591-22-miquel.raynal@bootlin.com> <20200526235003.5bb0ba91@collabora.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200527_004559_660433_60A592DF X-CRM114-Status: GOOD ( 27.55 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rickard Andersson , Richard Weinberger , linux-mtd@lists.infradead.org, Vignesh Raghavendra , Tudor Ambarus Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org Hi Boris, Boris Brezillon wrote on Tue, 26 May 2020 23:50:03 +0200: > On Tue, 26 May 2020 21:17:18 +0200 > Miquel Raynal wrote: > > > Extract the logic out of nand_choose_data_interface() to create a > > public helper that can be reused by manufacturer drivers. Add the > > possibility to provide a specific set of timings. > > > > Signed-off-by: Miquel Raynal > > --- > > drivers/mtd/nand/raw/internals.h | 3 + > > drivers/mtd/nand/raw/nand_base.c | 104 +++++++++++++++++++------------ > > 2 files changed, 66 insertions(+), 41 deletions(-) > > > > diff --git a/drivers/mtd/nand/raw/internals.h b/drivers/mtd/nand/raw/internals.h > > index c7357ae86eeb..5c49c4d1e231 100644 > > --- a/drivers/mtd/nand/raw/internals.h > > +++ b/drivers/mtd/nand/raw/internals.h > > @@ -90,6 +90,9 @@ int onfi_fill_data_interface(struct nand_chip *chip, > > int timing_mode); > > unsigned int > > onfi_find_closest_sdr_mode(const struct nand_sdr_timings *spec_timings); > > +int nand_choose_best_sdr_timings(struct nand_chip *chip, > > + struct nand_data_interface *iface, > > + struct nand_sdr_timings *spec_timings); > > int nand_get_features(struct nand_chip *chip, int addr, u8 *subfeature_param); > > int nand_set_features(struct nand_chip *chip, int addr, u8 *subfeature_param); > > int nand_read_page_raw_notsupp(struct nand_chip *chip, u8 *buf, > > diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c > > index 6a7edd2e1357..b2e833a8ab9d 100644 > > --- a/drivers/mtd/nand/raw/nand_base.c > > +++ b/drivers/mtd/nand/raw/nand_base.c > > @@ -1003,61 +1003,83 @@ static int nand_setup_data_interface(struct nand_chip *chip, int chipnr) > > return ret; > > } > > > > +/** > > + * nand_choose_best_sdr_timings - Pick up the best SDR timings that both the > > + * NAND controller and the NAND chip support > > + * @chip: the NAND chip > > + * @iface: the data interface (can eventually be updated) > > + * @spec_timings: specific timings, when not fitting the ONFI specification > > + * > > + * If specific timings are provided, use them. Otherwise, try to retrieve > > + * supported timing modes from ONFI information. Finally, if the NAND chip does > > + * not follow the ONFI specification, rely on the ->default_timing_mode > > + * specified in the nand_ids table. > > + */ > > +int nand_choose_best_sdr_timings(struct nand_chip *chip, > > + struct nand_data_interface *iface, > > + struct nand_sdr_timings *spec_timings) > > +{ > > + const struct nand_controller_ops *ops = chip->controller->ops; > > + int best_mode = 0, onfi_modes, mode, ret; > > + > > + iface->type = NAND_SDR_IFACE; > > + > > + if (spec_timings) { > > + iface->timings.sdr = *spec_timings; > > + iface->timings.mode = onfi_find_closest_sdr_mode(spec_timings); > > + > > + /* Verify the controller supports the requested interface */ > > + ret = ops->setup_data_interface(chip, > > + NAND_DATA_IFACE_CHECK_ONLY, > > + iface); > > + if (!ret) > > + return ret; > > + > > + /* Fallback to slower modes */ > > + best_mode = iface->timings.mode; > > + } else { > > + if (chip->parameters.onfi) { > > onfi_modes var should be declared here. Ok > > > + onfi_modes = chip->parameters.onfi->async_timing_mode; > > + best_mode = fls(onfi_modes) - 1; > > + } else { > > + best_mode = chip->onfi_timing_mode_default; > > + } > > + } > > + > > + > > + for (mode = best_mode; mode >= 0; mode--) { > > + ret = onfi_fill_data_interface(chip, iface, NAND_SDR_IFACE, > > + mode); > > + if (ret) > > + continue; > > In practice onfi_fill_data_interface() will only return an error if you > pass a type that's not SDR (not the case here, or a mode that's outside > the SDR mode bounds). Maybe we should just clamp the value/warn when > that happens and make onfi_fill_data_interface() a void function. Agreed, I'll call WARN_ON() in it and return void. This function should "never" fail. > > > + > > + ret = ops->setup_data_interface(chip, > > + NAND_DATA_IFACE_CHECK_ONLY, > > + iface); > > + if (!ret) > > + break; > > return 0; > > + } > > + > > + return 0; > > +} > > + > > /** > > * nand_choose_data_interface - find the best data interface and timings > > * @chip: The NAND chip > > * > > * Find the best data interface and NAND timings supported by the chip > > * and the driver. > > - * First tries to retrieve supported timing modes from ONFI information, > > - * and if the NAND chip does not support ONFI, relies on the > > - * ->onfi_timing_mode_default specified in the nand_ids table. After this > > - * function nand_chip->data_interface is initialized with the best timing mode > > - * available. > > + * After this function nand_chip->data_interface is initialized with the best > > + * timing mode available. > > * > > * Returns 0 for success or negative error code otherwise. > > */ > > static int nand_choose_data_interface(struct nand_chip *chip) > > { > > - int modes, mode, ret; > > - > > if (!nand_controller_has_setup_data_iface(chip)) > > return 0; > > > > - /* > > - * First try to identify the best timings from ONFI parameters and > > - * if the NAND does not support ONFI, fallback to the default ONFI > > - * timing mode. > > - */ > > - if (chip->parameters.onfi) { > > - modes = chip->parameters.onfi->async_timing_mode; > > - } else { > > - if (!chip->onfi_timing_mode_default) > > - return 0; > > - > > - modes = GENMASK(chip->onfi_timing_mode_default, 0); > > - } > > - > > - for (mode = fls(modes) - 1; mode >= 0; mode--) { > > - ret = onfi_fill_data_interface(chip, &chip->data_interface, > > - NAND_SDR_IFACE, mode); > > - if (ret) > > - continue; > > - > > - /* > > - * Pass NAND_DATA_IFACE_CHECK_ONLY to only check if the > > - * controller supports the requested timings. > > - */ > > - ret = chip->controller->ops->setup_data_interface(chip, > > - NAND_DATA_IFACE_CHECK_ONLY, > > - &chip->data_interface); > > - if (!ret) { > > - chip->onfi_timing_mode_default = mode; > > - break; > > - } > > - } > > - > > - return 0; > > + return nand_choose_best_sdr_timings(chip, &chip->data_interface, NULL); > > } > > > > /** > ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/