From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shamile Khan Date: 03 Feb 2004 19:47:40 -0500 Subject: [U-Boot-Users] environment not being used In-Reply-To: <20040131171252.96147C112A@atlas.denx.de> References: <20040131171252.96147C112A@atlas.denx.de> Message-ID: <1075855660.7664.95.camel@localhost.localdomain> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi, Just as a follow up, I conclude that U-boot treats flash reads exactly as sdram reads i.e. 32-bit accesses. So its not just about the environment variables. Most of the flash-based U-boot functionality wouldn't work for us unless we modify all the commands that have access to flash e.g md, imiinfo, bootm etc. A hardware fix (an 8-bit bus to our byte-mode flash chip) seems like the right way to go. Shamile On Sat, 2004-01-31 at 12:12, Wolfgang Denk wrote: > In message <1075423717.18221.233.camel@localhost.localdomain> you wrote: > > > > To get around this, we have a small program which is stored in FPGA > > bitstream and runs in FPGA on-chip memory (called BRAM). This program > > copies u-boot binary image from flash to sdram and jumps to it. This > > allows U-boot to run. However the problem is that the environment > > variables saved in flash are not being used even though U-boot has been > > configured with the CFG_ENV_IS_IN_FLASH option turned on. > > CFG_FLASH_BASE has been set to the flash base address of u-boot and when > > I use saveenv the environment is saved at the proper offset > > CFG_ENV_OFFSET. The only thing thats a bit different for my U-boot > > configuration is that CFG_MONITOR_BASE is set to the sdram base address > > where U-boot starts executing from instead of being set to > > CFG_FLASH_BASE. > > Normally U-Boot attempts to read the environment when starting from > the same position in memory where it will save it to when you issue a > "saveenv" command. You will have to modify U-Boot such that the > initialization reads from the "fixed" copy in RAM, while "saveenv" > saves to the address in flash, performing the 16-bit-expansion needed > for your setup. It seems obvious that a plain copy as usuall cannot > work on your system. > > Best regards, > > Wolfgang Denk > > -- > See us @ Embedded World, Nuremberg, Feb 17 - 19, Hall 12.0 Booth 440 > Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd at denx.de > Drun'? 'm not drun'! You woudn' dare call m' drun' if I was sober! > - Terry Pratchett, _Men at Arms_ >