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=-8.3 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 4DB95C433E0 for ; Tue, 19 May 2020 13:18:09 +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 20072206D4 for ; Tue, 19 May 2020 13:18:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ga96gATH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 20072206D4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.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=DYhUWVMPXuwYyBuMncyMOGw5HO5gILcsmFUOgv2itSs=; b=ga96gATHDXVi69 EUpFZ6LjBH+3ewnGqDFrHfWvElRxs7F4pUzKolTRTNbjzcNLNpCQBFnZTTTZ9l+bT8YQH+7OSmCR5 y/cfo+F0UV8jtmpT637JP+J5drA02LD3iY6jtZT3VUxxyyndz7PUOzDSHSSF5Vx2JfrnZDS4zsGBM Pm/2LJqWjTnD/JTu/TT7axzgQwsl+86ahW9/t7XHAFAG9ciasugJKRrM8p1LX7dArfCOD/ghiHHOV 1Zq3O2atcS5/UOi+6HzOFSdmtEQ24W/rUbSdNcmtTHurgDUsjJ0YKlhjAoV6n1qjssAMEecXpQugM zVgDoJSHi6agZ4GtR/aA==; 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 1jb288-0007N4-8F; Tue, 19 May 2020 13:18:00 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jb1sg-0002qz-DO for linux-mtd@lists.infradead.org; Tue, 19 May 2020 13:02:06 +0000 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 34C752A2309; Tue, 19 May 2020 14:02:00 +0100 (BST) Date: Tue, 19 May 2020 15:01:57 +0200 From: Boris Brezillon To: Miquel Raynal Subject: Re: [PATCH v2] mtd: rawnand: micron: Adapt the PAGE READ flow to constraint controllers Message-ID: <20200519150157.7b668605@collabora.com> In-Reply-To: <20200519123032.32547-1-miquel.raynal@bootlin.com> References: <20200519123032.32547-1-miquel.raynal@bootlin.com> Organization: Collabora X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200519_060202_829421_2F00D086 X-CRM114-Status: GOOD ( 26.75 ) 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: Michal Simek , Vignesh Raghavendra , Tudor Ambarus , Richard Weinberger , linux-mtd@lists.infradead.org, Thomas Petazzoni , Naga Sureshkumar Relli 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 On Tue, 19 May 2020 14:30:32 +0200 Miquel Raynal wrote: > There are controllers not able to just read data cycles on the > bus. There are controllers not able to do a change column. > > If we want to support both, we need to check which operation is > supported first. This is the exact same mechanism that is in use for > parameter page reads (ONFI/JEDEC) as the same problem occurs. > > Speed testing does not show any throughput penalty so we do not > optimize more than that. However it is likely that, in the future, a > more robust and exhaustive test will run at boot time to avoid > re-checking what is supported and what is not at every call. > > Signed-off-by: Miquel Raynal > Reviewed-by: Boris Brezillon > --- > > Changes in v2: > * Added a comment before each check which is a condensate of the > commit message. I don't see those comments :P. > * Collected Boris' R-by tag. > > drivers/mtd/nand/raw/nand_micron.c | 44 ++++++++++++++++++++++++------ > 1 file changed, 35 insertions(+), 9 deletions(-) > > diff --git a/drivers/mtd/nand/raw/nand_micron.c b/drivers/mtd/nand/raw/nand_micron.c > index b2b047b245f4..bbd0ffbae19a 100644 > --- a/drivers/mtd/nand/raw/nand_micron.c > +++ b/drivers/mtd/nand/raw/nand_micron.c > @@ -192,6 +192,7 @@ static int micron_nand_on_die_ecc_status_4(struct nand_chip *chip, u8 status, > struct micron_nand *micron = nand_get_manufacturer_data(chip); > struct mtd_info *mtd = nand_to_mtd(chip); > unsigned int step, max_bitflips = 0; > + bool use_datain = false; > int ret; > > if (!(status & NAND_ECC_STATUS_WRITE_RECOMMENDED)) { > @@ -211,8 +212,18 @@ static int micron_nand_on_die_ecc_status_4(struct nand_chip *chip, u8 status, > * in non-raw mode, even if the user did not request those bytes. > */ > if (!oob_required) { > - ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize, > - false, false); > + if (!nand_has_exec_op(chip) || > + !nand_read_data_op(chip, chip->oob_poi, mtd->oobsize, false, > + true)) > + use_datain = true; > + > + if (use_datain) > + ret = nand_read_data_op(chip, chip->oob_poi, > + mtd->oobsize, false, false); > + else > + ret = nand_change_read_column_op(chip, mtd->writesize, > + chip->oob_poi, > + mtd->oobsize, false); > if (ret) > return ret; > } > @@ -285,6 +296,7 @@ micron_nand_read_page_on_die_ecc(struct nand_chip *chip, uint8_t *buf, > int oob_required, int page) > { > struct mtd_info *mtd = nand_to_mtd(chip); > + bool use_datain = false; > u8 status; > int ret, max_bitflips = 0; > > @@ -300,14 +312,28 @@ micron_nand_read_page_on_die_ecc(struct nand_chip *chip, uint8_t *buf, > if (ret) > goto out; > > - ret = nand_exit_status_op(chip); > - if (ret) > - goto out; > + if (!nand_has_exec_op(chip) || > + !nand_read_data_op(chip, buf, mtd->writesize, false, true)) > + use_datain = true; > > - ret = nand_read_data_op(chip, buf, mtd->writesize, false, false); > - if (!ret && oob_required) > - ret = nand_read_data_op(chip, chip->oob_poi, mtd->oobsize, > - false, false); > + if (use_datain) { > + ret = nand_exit_status_op(chip); > + if (ret) > + goto out; > + > + ret = nand_read_data_op(chip, buf, mtd->writesize, false, > + false); > + if (!ret && oob_required) > + ret = nand_read_data_op(chip, chip->oob_poi, > + mtd->oobsize, false, false); > + } else { > + ret = nand_change_read_column_op(chip, 0, buf, mtd->writesize, > + false); > + if (!ret && oob_required) > + ret = nand_change_read_column_op(chip, mtd->writesize, > + chip->oob_poi, > + mtd->oobsize, false); > + } > > if (chip->ecc.strength == 4) > max_bitflips = micron_nand_on_die_ecc_status_4(chip, status, ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/