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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED 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 B2F2FC10F11 for ; Wed, 10 Apr 2019 07:16:33 +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 80E442133D for ; Wed, 10 Apr 2019 07:16:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="S8qnOZ4v" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 80E442133D 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=z7kS9/prozEFmP5T+H93AeCNwGWhfufGMmuopkKt29s=; b=S8qnOZ4vYzQxdO KkJqEn8UypNrw1RauI+ZQmO+Sry8u+w31t371DaoGxhUqeWT2eZN1iCYk7/hsAYR9NWlcGplK7TkE kBBBfdFVorg1kxBqbv3caRzQcl5yVnPuGOyUvdlJ/6vbFuDzF8E7J+Q3G1ftTgogx5WIoUfLOdEyi DseUIBsPNYTIrsOwsAo0PJIO9WUydZmY583wl73vUdeKk/0x9OG4Cp+tdhB9Khba1w27V4uXelNO7 rcq5CWbSkXI75Kslxtll2Hi1y68QvTesYo34ZuFFFspRwZuvo+WDoDfgvMr+0QEDzqygVx0yXQRMr lIfLQ8ry7w4lK8kpC1Sg==; 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 1hE7TC-0003Sa-Ub; Wed, 10 Apr 2019 07:16:30 +0000 Received: from relay9-d.mail.gandi.net ([217.70.183.199]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hE7T9-0003S2-Cj for linux-mtd@lists.infradead.org; Wed, 10 Apr 2019 07:16:29 +0000 X-Originating-IP: 90.88.18.121 Received: from xps13 (aaubervilliers-681-1-63-121.w90-88.abo.wanadoo.fr [90.88.18.121]) (Authenticated sender: miquel.raynal@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id B6D7EFF808; Wed, 10 Apr 2019 07:16:13 +0000 (UTC) Date: Wed, 10 Apr 2019 09:16:12 +0200 From: Miquel Raynal To: masonccyang@mxic.com.tw Subject: Re: [PATCH] mtd: rawnand: Add Macronix NAND read retry and randomizer support Message-ID: <20190410091612.229c91b4@xps13> In-Reply-To: References: <1554780172-23111-1-git-send-email-masonccyang@mxic.com.tw> <20190409090427.22de9917@collabora.com> <20190409114701.744c2c8c@collabora.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (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-20190410_001627_584156_231C4188 X-CRM114-Status: GOOD ( 19.21 ) 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: bbrezillon@kernel.org, juliensu@mxic.com.tw, richard@nod.at, linux-kernel@vger.kernel.org, marek.vasut@gmail.com, Boris Brezillon , linux-mtd@lists.infradead.org, computersforpeace@gmail.com, dwmw2@infradead.org, zhengxunli@mxic.com.tw Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org SGkgTWFzb24sCgptYXNvbmNjeWFuZ0BteGljLmNvbS50dyB3cm90ZSBvbiBXZWQsIDEwIEFwciAy MDE5IDA5OjE0OjE0ICswODAwOgoKPiBIaSBCb3JpcywKPiAKPiA+IAo+ID4gU3ViamVjdAo+ID4g Cj4gPiBSZTogW1BBVENIXSBtdGQ6IHJhd25hbmQ6IEFkZCBNYWNyb25peCBOQU5EIHJlYWQgcmV0 cnkgYW5kIHJhbmRvbWl6ZXIgICAKPiBzdXBwb3J0Cj4gPiAKPiA+IE9uIFR1ZSwgOSBBcHIgMjAx OSAxNzozNTozOSArMDgwMAo+ID4gbWFzb25jY3lhbmdAbXhpYy5jb20udHcgd3JvdGU6Cj4gPiAg IAo+ID4gPiA+ID4gKwo+ID4gPiA+ID4gK3N0YXRpYyBjb25zdCBzdHJ1Y3Qga29ial9hdHRyaWJ1 dGUgc3lzZnNfbXhpY19uYW5kID0KPiA+ID4gPiA+ICsgICBfX0FUVFIobmFuZF9yYW5kb20sIFNf SVJVR08gfCBTX0lXVVNSLAo+ID4gPiA+ID4gKyAgICAgICAgICBteGljX25hbmRfcmFuZF90eXBl X3Nob3csCj4gPiA+ID4gPiArICAgICAgICAgIG14aWNfbmFuZF9yYW5kX3R5cGVfc3RvcmUpOyAg IAo+ID4gPiA+IAo+ID4gPiA+IE5vLCB3ZSBkb24ndCB3YW50IHRvIGV4cG9zZSB0aGF0IHRocm91 Z2ggYSBzeXNmcyBmaWxlLCBlc3BlY2lhbGx5ICAgCj4gc2luY2UKPiA+ID4gPiBjaGFuZ2luZyB0 aGUgcmFuZG9taXplciBjb25maWcgbWVhbnMgbWFraW5nIHRoZSBOQU5EIHVucmVhZGFibGUgZm9y Cj4gPiA+ID4gdGhvc2UgdGhhdCBoYXZlIHVzZWQgaXQgYmVmb3JlIHRoZSBjaGFuZ2UuCj4gPiA+ ID4gICAKPiA+ID4gCj4gPiA+IE91ciBvbi1kaWUgcmFuZG9taXplciBpcyBzdGlsbCByZWFkYWJs ZSBmcm9tIHVzZXIgYWZ0ZXIgdGhlIGZ1bmN0aW9uIAo+ID4gPiBpcyBlbmFibGVkLiAgCj4gPiAK PiA+IFlvdSBtZWFuIHRoZSBtZW1vcnkgaXMgc3RpbGwgcmVhZGFibGUgbm8gbWF0dGVyIHRoZSBy YW5kb21pemVyIHN0YXRlLgo+ID4gTm90IHN1cmUgaG93IHRoYXQncyBwb3NzaWJsZSwgYnV0IG9r YXkuCgpTbyBpZiB5b3Ugd3JpdGUgbm9uLXJhbmRvbWl6ZWQgZGF0YSB0byB0aGUgTkFORCBjaGlw LCB0aGVuIGVuYWJsZSB0aGUKcmFuZG9taXplciBlbiByZWFkIGJhY2sgdGhlIGRhdGEsIGFsbCB3 aWxsIGJlIG9rPwoKQW5kIGlmIHJhbmRvbWl6ZWQgZGF0YSBpcyB3cml0dGVuIHRvIHRoZSBOQU5E IGNoaXAgYW5kIHdlIGRpc2FibGUgdGhlCnJhbmRvbWl6ZXIsIHRoZW4gdGhlIGRhdGEgd2lsbCBh bHNvIGJlIGNvcnJlY3Q/Cgo+ID4gICAKPiA+ID4gVGhpcyByYW5kb21pemVyIGlzIGp1c3QgbGlr ZSBhIGludGVybmFsIG1lbW9yeSBjZWxsIAo+ID4gPiByZWxpYWJpbGl0eSBlbmhhbmNlZC4gIAo+ ID4gCj4gPiBXaHkgZG9uJ3QgeW91IGVuYWJsZSBpdCBieSBkZWZhdWx0IHRoZW4/ICAKPiAKPiBU aGUgcGVuYWx0eSBvZiByYW5kb21pemVyIGlzIHJlYWQvd3JpdGUgcGVyZm9ybWFuY2UgZG93bi4K PiBpLmUsLiB0UFJPRyAzMDAgdXMgdG8gMzQwIHVzIChyYW5kb21pemVyIGVuYWJsZSkKPiB0aGVy ZWZvcmUsIGRpc2FibGUgaXQgYnkgZGVmYXVsdC4KCklzIHRoaXMgaW5mbyBzb21ld2hlcmUgaW4g dGhlIE9ORkkgcGFyYW0gcGFnZT8gSSBzdXBwb3NlIG9uY2UKcmFuZG9taXphdGlvbiBpcyBlbmFi bGVkIHdlIHNob3VsZCBhbHNvIHR3ZWFrIHRoZSB0aW1pbmdzIGFuZCB2ZXJpZnkKdGhhdCB0aGUg Y29udHJvbGxlciBzdXBwb3J0cyBpdC4KCj4gPiA+IEl0IGNvdWxkIGJlIGVuYWJsZSBhdCBhbnkg dGltZSB3aXRoIE9UUCBiaXQgZnVuY3Rpb24gYW5kIHRoYXQncyB3aHkKPiA+ID4gd2UgcGF0Y2gg aXQgYnkgc3lzLWZzLiAgCj4gPiAKPiA+IFNvcnJ5LCBidXQgdGhhdCdzIG5vdCBhIGdvb2QgcmVh c29uIHRvIGV4cG9zZSB0aGF0IHRocm91Z2ggc3lzZnMuICAKPiAKPiBBbnkgZ29vZCB3YXkgdG8g ZXhwb3NlIHJhbmRvbWl6ZXIgZnVuY3Rpb24gZm9yIHVzZXIgPwo+IAo+IHRoYW5rcyAmIGJlc3Qg cmVnYXJkcywKPiBNYXNvbgo+IAoKVGhhbmtzLApNaXF1w6hsCgpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KTGludXggTVREIGRpc2N1c3Npb24g bWFpbGluZyBsaXN0Cmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8v bGludXgtbXRkLwo= 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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 562C7C10F11 for ; Wed, 10 Apr 2019 07:16:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 313902084B for ; Wed, 10 Apr 2019 07:16:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728160AbfDJHQT convert rfc822-to-8bit (ORCPT ); Wed, 10 Apr 2019 03:16:19 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:45527 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726725AbfDJHQS (ORCPT ); Wed, 10 Apr 2019 03:16:18 -0400 X-Originating-IP: 90.88.18.121 Received: from xps13 (aaubervilliers-681-1-63-121.w90-88.abo.wanadoo.fr [90.88.18.121]) (Authenticated sender: miquel.raynal@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id B6D7EFF808; Wed, 10 Apr 2019 07:16:13 +0000 (UTC) Date: Wed, 10 Apr 2019 09:16:12 +0200 From: Miquel Raynal To: masonccyang@mxic.com.tw Cc: "Boris Brezillon" , bbrezillon@kernel.org, computersforpeace@gmail.com, dwmw2@infradead.org, juliensu@mxic.com.tw, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, marek.vasut@gmail.com, richard@nod.at, zhengxunli@mxic.com.tw Subject: Re: [PATCH] mtd: rawnand: Add Macronix NAND read retry and randomizer support Message-ID: <20190410091612.229c91b4@xps13> In-Reply-To: References: <1554780172-23111-1-git-send-email-masonccyang@mxic.com.tw> <20190409090427.22de9917@collabora.com> <20190409114701.744c2c8c@collabora.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mason, masonccyang@mxic.com.tw wrote on Wed, 10 Apr 2019 09:14:14 +0800: > Hi Boris, > > > > > Subject > > > > Re: [PATCH] mtd: rawnand: Add Macronix NAND read retry and randomizer > support > > > > On Tue, 9 Apr 2019 17:35:39 +0800 > > masonccyang@mxic.com.tw wrote: > > > > > > > + > > > > > +static const struct kobj_attribute sysfs_mxic_nand = > > > > > + __ATTR(nand_random, S_IRUGO | S_IWUSR, > > > > > + mxic_nand_rand_type_show, > > > > > + mxic_nand_rand_type_store); > > > > > > > > No, we don't want to expose that through a sysfs file, especially > since > > > > changing the randomizer config means making the NAND unreadable for > > > > those that have used it before the change. > > > > > > > > > > Our on-die randomizer is still readable from user after the function > > > is enabled. > > > > You mean the memory is still readable no matter the randomizer state. > > Not sure how that's possible, but okay. So if you write non-randomized data to the NAND chip, then enable the randomizer en read back the data, all will be ok? And if randomized data is written to the NAND chip and we disable the randomizer, then the data will also be correct? > > > > > This randomizer is just like a internal memory cell > > > reliability enhanced. > > > > Why don't you enable it by default then? > > The penalty of randomizer is read/write performance down. > i.e,. tPROG 300 us to 340 us (randomizer enable) > therefore, disable it by default. Is this info somewhere in the ONFI param page? I suppose once randomization is enabled we should also tweak the timings and verify that the controller supports it. > > > It could be enable at any time with OTP bit function and that's why > > > we patch it by sys-fs. > > > > Sorry, but that's not a good reason to expose that through sysfs. > > Any good way to expose randomizer function for user ? > > thanks & best regards, > Mason > Thanks, Miquèl