From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ivan Khoronzhuk Subject: Re: [PATCH 2/3] mtd: davinci-nand: add dts property for NAND_NO_SUBPAGE_WRITE option Date: Thu, 20 Mar 2014 21:26:29 +0200 Message-ID: <532B40E5.4070201@ti.com> References: <1395335184-4745-1-git-send-email-ivan.khoronzhuk@ti.com> <1395335184-4745-3-git-send-email-ivan.khoronzhuk@ti.com> <532B2183.2080309@ti.com> <20140320172912.GW31517@norris-Latitude-E6410> <532B2766.6090506@ti.com> <532B2D3F.6050004@ti.com> <20140320185452.GB21018@ld-irv-0074> <532B3D74.6070703@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <532B3D74.6070703@ti.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+gldm-linux-mtd-36=gmane.org@lists.infradead.org To: Santosh Shilimkar , Brian Norris Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, grygorii.strashko@ti.com, Russell King - ARM Linux , pawel.moll@arm.com, ijc+devicetree@hellion.org.uk, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Murali Karicheri , robh+dt@kernel.org, linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, rob@landley.net, galak@codeaurora.org, David Woodhouse , Warner Losh List-Id: devicetree@vger.kernel.org On 03/20/2014 09:11 PM, Santosh Shilimkar wrote: > On Thursday 20 March 2014 02:54 PM, Brian Norris wrote: >> On Thu, Mar 20, 2014 at 02:02:39PM -0400, Santosh Shilimkar wrote: >>> On Thursday 20 March 2014 01:44 PM, Warner Losh wrote: >>>> I though sub page writing was one of the fields in the onfi and/or jedec(toggle) meta data structures. Have you looked there? >>>> >>> Am not sure if I follow you. The limitation is from the TI NAND controller(AEMIF) and >>> not the NAND memory. >> That doesn't match the patch description, which says "that flash doesn't >> support subpage writing". Flash != flash controller. >> > Patch description is indeed doesn't reflect the actual issue. > >> Which one is it? If it's a controller limitation, I think we should be >> able to pull this from a "compatible" property, no? >> > Just to be accurate, the limitation(bug) is on the controller found on Keystone > SOCs. AEMIF controller is also used on DaVinci SOCs which don't seems to have > any issue. So even for compatible, you need to add keystone specific one. > Hence thought dt property is better option. > > regards, > Santosh > I will use compatible approach. We have keystone compatible in k2hk-evm.dts, so I need to add it only in the davinci-nand driver. I will add the following: if (of_device_is_compatible(np, "ti,keystone-nand")) { pdata->options |= NAND_NO_SUBPAGE_WRITE; } ... static const struct of_device_id davinci_nand_of_match[] = { {.compatible = "ti,davinci-nand", }, {.compatible = "ti,keystone-nand", }, {}, }; -- Regards, Ivan Khoronzhuk ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/