From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Date: Sun, 10 May 2015 19:43:52 +0200 Subject: [U-Boot] [PATCHv3] mtd: sf: Add CONFIG_SPI_N25Q256A_RESET for software-reset In-Reply-To: <201505101825.59885.marex@denx.de> References: <1412176391-24475-1-git-send-email-sr@denx.de> <20150510104952.GB22034@amd> <201505101825.59885.marex@denx.de> Message-ID: <20150510174352.GA28291@amd> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Sun 2015-05-10 18:25:59, Marek Vasut wrote: > On Sunday, May 10, 2015 at 02:24:01 PM, Jagan Teki wrote: > > On 10 May 2015 at 16:19, Pavel Machek wrote: > > > On Sun 2015-05-10 11:15:41, Pavel Machek wrote: > > > Add reset for N25Q256A SPI NOR, as U-Boot SPL 2013-socfpga (only > > > version working on that board) sets 4-byte addressing mode. > > > > > > Signed-off-by: Pavel Machek > > So, I took one more look into the datasheet [1]. With this chip, which > is 128Mbit (16MByte), you don't even use 4-byte addressing so you don't > care about it at all. > > But you actually do care about it if your hardware is broken and you use > the N25Q256A [2] part. If the problem really is just between the > U-Boot No, I actually care whenever I use the U-boot SPL 2013, which is the only option today. And I explained it to you already. (Additionally, hardware might be broken. That has nothing to do with _this_ problem). > SPL and U-Boot (which I doubt btw), you can probably augment U-Boot such > that it reads FSR (Flag Status Register, see page 27, table 17, bit 0). > This bit tells you whether the part is in 3-byte or 4-byte mode and you > can read this register in either mode. How does reading Micron-specific register help with code being too Micron-specific is unclear to me. Pavel > > Same applies to N25Q512A [3], FSR bit 0 indicates the mode. > > [1] https://www.micron.com/~/media/documents/products/data-sheet/nor- > flash/serial-nor/n25q/n25q_128mb_1_8v_65nm.pdf > [2] https://www.micron.com/~/media/documents/products/data-sheet/nor- > flash/serial-nor/n25q/n25q_256mb_3v_65nm.pdf > [3] https://www.micron.com/~/media/documents/products/data-sheet/nor- > flash/serial-nor/n25q/n25q_512mb_1ce_3v_65nm.pdf > > Best regards, > Marek Vasut -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html