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,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 5DB4EC83006 for ; Wed, 29 Apr 2020 16:04:26 +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 2CB0D2072A for ; Wed, 29 Apr 2020 16:04:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="O7GVMJBl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2CB0D2072A 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=Z0NDi9iFSn+Fnmo3a5dRDKaBW7tBLV+N3WXXrVSWfjg=; b=O7GVMJBlwvjmkU 1KteUp8rhp0My6BGeC9stZJD6dJdHQs9xzGTUf4WLqK+cQe3Uk1LDAq7xprunbLeACv4Vr7vtGhJn /3F3GR9fesWBtk5EM1D+5lrYREqebv48tBEh/0ncU7FdTKmkgw9mxaW0IEL6Hei7Gyg24wqqRWmkM HvVUt0Lpq07DEKwS08optuF6mq443n7VY8mnOJIxLWCuLqJZ/xysvyEtNSgTXwERwJ/ai1lph3CWo nCVQWUeQq1VHuOG/yk9k+EBF1QhEBOC1YE/Tx/Ry91q8BFVEx5DcREz/xGm22hY61QO8yIdpvbNBS /Gs36sDn3SmJkyBh1X4Q==; 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 1jTpC1-00036S-Ab; Wed, 29 Apr 2020 16:04:13 +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 1jTpBx-00035s-T5 for linux-mtd@lists.infradead.org; Wed, 29 Apr 2020 16:04:11 +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 2848C2A06C2; Wed, 29 Apr 2020 17:04:08 +0100 (BST) Date: Wed, 29 Apr 2020 18:04:05 +0200 From: Boris Brezillon To: Miquel Raynal , Tudor Ambarus Subject: Re: [PATCH v2 08/11] mtd: rawnand: jedec: Adapt the parameter page read to constraint controllers Message-ID: <20200429180405.5bf69447@collabora.com> In-Reply-To: <20200429155540.22048-9-miquel.raynal@bootlin.com> References: <20200429155540.22048-1-miquel.raynal@bootlin.com> <20200429155540.22048-9-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-20200429_090410_068321_3D8F848B X-CRM114-Status: GOOD ( 24.74 ) 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 , 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 Wed, 29 Apr 2020 17:55:37 +0200 Miquel Raynal wrote: > We already know that there are controllers not able to read the three > copies of the parameter page in one go. The workaround was to first > request the controller to assert command and address cycles on the > NAND bus to trigger a parameter page read, and then do a read > operation for each page. > > But there are also controllers which are not able to split the > parameter page read between the command/address cycles and the actual > data operation. > > All controllers are expected to be able to change the read column > though. So let's use a regular parameter page read operation for the > first iteration and use a change read column operation for the > following copies. > > The extra command and address cycles sent over the NAND bus are > negligible compared to the amount of data that is being transferred > anyway. > > Signed-off-by: Miquel Raynal > --- > drivers/mtd/nand/raw/nand_jedec.c | 28 +++++++++++++++------------- > 1 file changed, 15 insertions(+), 13 deletions(-) > > diff --git a/drivers/mtd/nand/raw/nand_jedec.c b/drivers/mtd/nand/raw/nand_jedec.c > index 15937e02c64f..b2be9056759a 100644 > --- a/drivers/mtd/nand/raw/nand_jedec.c > +++ b/drivers/mtd/nand/raw/nand_jedec.c > @@ -25,7 +25,7 @@ int nand_jedec_detect(struct nand_chip *chip) > { > struct mtd_info *mtd = nand_to_mtd(chip); > struct nand_memory_organization *memorg; > - struct nand_jedec_params *p; > + struct nand_jedec_params *p = NULL, *pbuf; Looks like you've merged 2 different commits here. I remember you had a separate commit adding pbuf to avoid an extra memcpy(). > struct jedec_ecc_info *ecc; > int jedec_version = 0; > char id[5]; > @@ -40,25 +40,25 @@ int nand_jedec_detect(struct nand_chip *chip) > return 0; > > /* JEDEC chip: allocate a buffer to hold its parameter page */ > - p = kzalloc(sizeof(*p), GFP_KERNEL); > - if (!p) > + pbuf = kzalloc(sizeof(*pbuf) * JEDEC_PARAM_PAGES, GFP_KERNEL); > + if (!pbuf) > return -ENOMEM; > > - ret = nand_read_param_page_op(chip, 0x40, NULL, 0); > - if (ret) { > - ret = 0; > - goto free_jedec_param_page; > - } > - > for (i = 0; i < JEDEC_PARAM_PAGES; i++) { > - ret = nand_read_data_op(chip, p, sizeof(*p), true); > + if (!i) > + ret = nand_read_param_page_op(chip, 0x40, &pbuf[i], > + sizeof(*pbuf)); > + else > + ret = nand_change_read_column_op(chip, sizeof(*pbuf) * i, > + &pbuf[i], sizeof(*pbuf), > + true); > if (ret) { > ret = 0; > goto free_jedec_param_page; > } > > - crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)p, 510); > - if (crc == le16_to_cpu(p->crc)) > + crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 510); > + if (crc == le16_to_cpu(pbuf[i].crc)) > break; > } > > @@ -67,6 +67,8 @@ int nand_jedec_detect(struct nand_chip *chip) > goto free_jedec_param_page; > } > > + p = pbuf; > + > /* Check version */ > val = le16_to_cpu(p->revision); > if (val & (1 << 2)) > @@ -122,6 +124,6 @@ int nand_jedec_detect(struct nand_chip *chip) > ret = 1; > > free_jedec_param_page: > - kfree(p); > + kfree(pbuf); > return ret; > } ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/