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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=no 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 1DED3C433DB for ; Thu, 28 Jan 2021 22:12:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DAD2364DF6 for ; Thu, 28 Jan 2021 22:12:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231250AbhA1WMA convert rfc822-to-8bit (ORCPT ); Thu, 28 Jan 2021 17:12:00 -0500 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:32915 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbhA1WL5 (ORCPT ); Thu, 28 Jan 2021 17:11:57 -0500 X-Originating-IP: 86.210.203.150 Received: from xps13 (lfbn-tou-1-972-150.w86-210.abo.wanadoo.fr [86.210.203.150]) (Authenticated sender: miquel.raynal@bootlin.com) by relay2-d.mail.gandi.net (Postfix) with ESMTPSA id A951F40007; Thu, 28 Jan 2021 22:11:11 +0000 (UTC) Date: Thu, 28 Jan 2021 23:11:10 +0100 From: Miquel Raynal To: mdalam@codeaurora.org Cc: manivannan.sadhasivam@linaro.org, richard@nod.at, vigneshr@ti.com, boris.brezillon@collabora.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, sricharan@codeaurora.org Subject: Re: [PATCH V3] mtd: rawnand: qcom: update last code word register Message-ID: <20210128231110.64266932@xps13> In-Reply-To: <769ea3fe77eab9b37d863251e97bcb29@codeaurora.org> References: <1610251305-20792-1-git-send-email-mdalam@codeaurora.org> <20210114165325.3d510355@xps13> <769ea3fe77eab9b37d863251e97bcb29@codeaurora.org> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, mdalam@codeaurora.org wrote on Fri, 29 Jan 2021 03:18:46 +0530: > On 2021-01-14 21:23, Miquel Raynal wrote: > > Hello, > > > > Md Sadre Alam wrote on Sun, 10 Jan 2021 > > 09:31:45 +0530: > > > >> From QPIC version 2.0 onwards new register got added to > > > > a > > > >> read last codeword. This change will update the same. > > > > the? ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > Please reword this sentence. > > Fixed this in V4 patch. > > > >> For first three code word READ_LOCATION_n register will be > >> use.For last code word READ_LOCATION_LAST_CW_n register will be > >> use. > > > > "For the first three codewords, READ_LOCATION_n registers will be used. > > The last codeword register will be accessed through > > READ_LOCATION_LAST_CW_n." > > > > Also, please specify what these registers store. > > The location register is mainly use for reading controller > buffer via BAM mode. The bits of the register "NAND_READ_LOCATION_LAST_CW_n, n=0..4" > as follow: Perhaps what I do not understand is: when is this "last_cw" register more useful than the previous set? > [9:0]-bits : (OFFSET) This bit defines the offset from the buffer base address to be picked up for DMA. > [25:16]-bits: (SIZE) This bit of every register will define the size of the chunk for DMA. > 31-bit : (LAST) If this bit is set, the controller takes the particular register to specify the last chunk > of data made available for DMA. This chunk is part of the internal buffer of the controller. > > > Thanks, Miquèl