From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wg0-f42.google.com ([74.125.82.42]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Ytjbm-0000Ih-Cv for linux-mtd@lists.infradead.org; Sat, 16 May 2015 21:27:00 +0000 Received: by wguv19 with SMTP id v19so87764766wgu.1 for ; Sat, 16 May 2015 14:26:36 -0700 (PDT) Message-ID: <5557B54B.9010307@vanguardiasur.com.ar> Date: Sat, 16 May 2015 18:23:23 -0300 From: Ezequiel Garcia MIME-Version: 1.0 To: Antoine Tenart Subject: Re: [PATCH v5 05/12] mtd: pxa3xx_nand: rework flash detection and timing setup References: <1431356341-31640-1-git-send-email-antoine.tenart@free-electrons.com> <1431356341-31640-6-git-send-email-antoine.tenart@free-electrons.com> <555128F0.30702@vanguardiasur.com.ar> <20150512143943.GC32171@kwain> In-Reply-To: <20150512143943.GC32171@kwain> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: zmxu@marvell.com, boris.brezillon@free-electrons.com, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, jszhang@marvell.com, computersforpeace@gmail.com, dwmw2@infradead.org, linux-arm-kernel@lists.infradead.org, sebastian.hesselbarth@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 05/12/2015 11:39 AM, Antoine Tenart wrote: > Ezequiel, > > On Mon, May 11, 2015 at 07:10:56PM -0300, Ezequiel Garcia wrote: >> >> On 05/11/2015 11:58 AM, Antoine Tenart wrote: >> [..] >>> - >>> - /* calculate flash information */ >>> - host->read_id_bytes = (f->page_size == 2048) ? 4 : 2; >>> - >> >> [..] >>> @@ -1732,6 +1669,7 @@ static int alloc_nand_resource(struct platform_device *pdev) >>> host->mtd = mtd; >>> host->cs = cs; >>> host->info_data = info; >>> + host->read_id_bytes = 4; >> >> Are you sure this is correct? The value is set according to the page >> size before this patch. > > Before reading the ID, the pxa3xx driver uses a default configuration, > builtin_flash_types[0], which defines a page size of 2048 leading to set > host->read_id_bytes to 4. > > I'm using this default value here. > > There might be an issue, as host->read_id_bytes isn't updated after > reading the ID (and getting the actual page size). I don't know if this > can be a problem. I can modify pxa3xx_nand_config_flash() to update > host->read_id_bytes if needed. What do you think? > Well, once the device is detected, READ_ID shouldn't be used, so I'm not sure what's the point of that. -- Ezequiel Garcia, VanguardiaSur www.vanguardiasur.com.ar