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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 91005C43381 for ; Wed, 27 Feb 2019 10:27:47 +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 6014720449 for ; Wed, 27 Feb 2019 10:27:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="k6lfin8F" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6014720449 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.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:In-Reply-To:MIME-Version:References: 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=o4RhVCT5flq7DrMoKCL6IJSjHkbSMOY3NT9zVDc0Jx0=; b=k6lfin8FqVE9KJ HBA3/6biowhhq8MQfxq21W1IPERZlT9zHL/IesLoPAma27gnbFRxbgBn4kgb3ru0XD+REzm/Tj7JR 9GpJmPa6dir1lpNvHkgI8omBk/oYiD1CS2t4Aon3EhRt/RLuwWoaRSWmLHaqZBHvPJqrObNHaLGGg HvSQyCzdyYS+f6u59mE1apTyQmwsnxPG7vw4RY6tn2HwM06DamlzYbE4YZmINlF4IhD7vsSdqhdct wDUKL64TlmUI4EqsBXMzdyvcHQ7lBw9iPQw0rnJer3v7wvHCT8tfkaUXbQxRX707IMwka+MVBn5t7 /kxMCUfyXy3Icgpglb8w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gywRE-0002Ar-VI; Wed, 27 Feb 2019 10:27:44 +0000 Received: from mga06.intel.com ([134.134.136.31]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gywRB-0002A6-1A for linux-mtd@lists.infradead.org; Wed, 27 Feb 2019 10:27:42 +0000 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Feb 2019 02:27:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,419,1544515200"; d="scan'208";a="118147955" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.157]) by orsmga007.jf.intel.com with SMTP; 27 Feb 2019 02:27:33 -0800 Received: by lahna (sSMTP sendmail emulation); Wed, 27 Feb 2019 12:27:32 +0200 Date: Wed, 27 Feb 2019 12:27:32 +0200 From: Mika Westerberg To: "Sverdlin, Alexander (Nokia - DE/Ulm)" Subject: Re: [PATCH v2] spi-nor: intel-spi: Avoid crossing 4K address boundary on read/write Message-ID: <20190227102732.GU2696@lahna.fi.intel.com> References: <20190226112334.401-1-alexander.sverdlin@nokia.com> <20190227095617.20968-1-alexander.sverdlin@nokia.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190227095617.20968-1-alexander.sverdlin@nokia.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190227_022741_120978_4A3231D6 X-CRM114-Status: GOOD ( 20.40 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bin Meng , "Porte, Romain \(Nokia - FR/Paris-Saclay\)" , Boris Brezillon , Richard Weinberger , Tudor Ambarus , "stable@vger.kernel.org" , Marek Vasut , "linux-mtd@lists.infradead.org" , "Fabreges, Pascal \(Nokia - FR/Paris-Saclay\)" , Brian Norris , David Woodhouse 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, Feb 27, 2019 at 09:57:15AM +0000, Sverdlin, Alexander (Nokia - DE/Ulm) wrote: > It was observed that reads crossing 4K address boundary are failing. > > This limitation is mentioned in Intel documents: > > Intel(R) 9 Series Chipset Family Platform Controller Hub (PCH) Datasheet: > > "5.26.3 Flash Access > Program Register Access: > * Program Register Accesses are not allowed to cross a 4 KB boundary..." > > Enhanced Serial Peripheral Interface (eSPI) > Interface Base Specification (for Client and Server Platforms): > > "5.1.4 Address > For other memory transactions, the address may start or end at any byte > boundary. However, the address and payload length combination must not > cross the naturally aligned address boundary of the corresponding Maximum > Payload Size. It must not cross a 4 KB address boundary." > > Avoid this by splitting an operation crossing the boundary into two > operations. > > Cc: stable@vger.kernel.org > Reported-by: Romain Porte > Tested-by: Pascal Fabreges > Signed-off-by: Alexander Sverdlin > --- > Changelog: > v2: More macros! As Mika suggested. > > drivers/mtd/spi-nor/intel-spi.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/mtd/spi-nor/intel-spi.c b/drivers/mtd/spi-nor/intel-spi.c > index af0a220..8c279c4 100644 > --- a/drivers/mtd/spi-nor/intel-spi.c > +++ b/drivers/mtd/spi-nor/intel-spi.c > @@ -632,6 +632,10 @@ static ssize_t intel_spi_read(struct spi_nor *nor, loff_t from, size_t len, > while (len > 0) { > block_size = min_t(size_t, len, INTEL_SPI_FIFO_SZ); > > + /* Read cannot cross 4K boundary */ > + blocksize = min(from + block_size, round_up(from + 1, SZ_4K)) - > + from; Nit: It looks better if you put it into one line like: blocksize = min(from + block_size, round_up(from + 1, SZ_4K)) - from; Regardless of that, Acked-by: Mika Westerberg ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/