From mboxrd@z Thu Jan 1 00:00:00 1970 From: David George Date: Fri, 17 Oct 2008 13:01:48 -0400 Subject: [U-Boot] [PATCH] NAND Send RESET before initial READID Message-ID: <48F8C4FC.7030807@harktech.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de We had a problem where NAND device ID would be corrupted after a power-cycle. According to the Micron datasheet it requires a RESET after power-up before any commands may be issued. Without this patch the manufacturer ID would be correct, but the device ID, cellinfo and extra ID would be incorrect. Signed-off-by: David George --- diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 0913bb8..3b9552d 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2360,6 +2360,12 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, /* Select the device */ chip->select_chip(mtd, 0); + /* + * Micron needs a RESET after power up before issuing + * any other commands + */ + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + /* Send the command for reading device ID */ chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); -- David George Hark Technologies http://harktech.com