From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-bk0-f49.google.com ([209.85.214.49]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1SUBHL-0002OR-MS for linux-mtd@lists.infradead.org; Tue, 15 May 2012 06:30:41 +0000 Received: by bkwj4 with SMTP id j4so5837557bkw.36 for ; Mon, 14 May 2012 23:30:34 -0700 (PDT) Message-ID: <4FB1F808.9080500@gmail.com> Date: Tue, 15 May 2012 08:30:32 +0200 From: Thomas Weber MIME-Version: 1.0 To: "Mohammed, Afzal" Subject: Re: [PATCH v4 04/39] ARM: OMAP2+: gpmc: Acquire NAND CS value References: <10220de398d22fad5de783d8f58fc55ebac85338.1335874494.git.afzal@ti.com> <4FA05292.7030902@ti.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "tony@atomide.com" , "artem.bityutskiy@linux.intel.com" , "linux-omap@vger.kernel.org" , "linux-mtd@lists.infradead.org" List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hello Afzal, On 05/14/12 12:33, Mohammed, Afzal wrote: > Hi All, > > On Thu, May 03, 2012 at 14:12:11, Mohammed, Afzal wrote: > >>>> Some boards depend on bootloader to update chip select value for NAND. >>>> It is felt that Kernel should not depend on bootloader to get CS, as >>>> for a particular board CS is hardwired and is fixed, hence this can >>>> directly be updated in Kernel. But as CS value for boards that depend >>>> on this behaviour is not available, educate gpmc driver to acquire >>>> chip select value for NAND. this ideally should be removed once CS >>>> for those boards are available. >>> Do you know how many boards require this? If so which are those boards? >> devkit8000, beagle board, omap3touchbook, overo. >> >> Beagle board, found out to be zero. > I need a help. > > Can someone familiar with boards - devkit8000, omap3touchbook, overo boards, > let me know GPMC CS on which NAND is connected. On Devkit8000 the NAND is connected to CS0. I thought that all NAND devices for booting are connected to CS0, because of ROM code? According to spruf98w.pdf: 25.4.7.4 NAND ... * The device is connected to CS0. ... Regards, Thomas > Hi Tony, > > I am planning to provide actual CS # used for NAND on above boards instead of > finding the value at runtime. Is there any reason that NAND CS# is found out > at runtime ? (hence remove necessity of omap_nand_flash_init()). > > Presence of this also causes an additional dependency of bootloader. > > As CS # depends on wiring on the board, my understanding is that it will be > fixed for a given board. Are you ok if acquiring NAND CS # is removed ? > > Removal of this helps in simplifying gpmc driver (undergoing conversion). > > Regards > Afzal > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html