ColdFire/68K Microcontrollers and Processors中的主题 Re: MCV5485evb new Linux (2.6.25) BSP U-Boot environment variable problems

MCV5485evb new Linux (2.6.25) BSP U-Boot environment variable problems

jkimble — Mon, 27 Oct 2008 21:59:50 GMT

I've had to move where the environment variables are stored in U-Boot because I'm using a different flash than on the evaluation board (P33) that has two flash chips with their CS tied together to give me a 32 bit x 64 Mb of flash memory. I had to adjust the following:

#define CFG_ENV_OFFSET          0x00030000   /* Must be sector aligned */
#define CFG_ENV_SIZE            0x00002000
#define CFG_ENV_SECT_SIZE       0x00010000
#define CFG_ENV_IS_IN_FLASH     1
#define CFG_ENV_IS_EMBEDDED     1

and that got rid of some errors I was seeing when saving to flash (offset was not on a sector boundary) and I had to modify the loader map to allow for the bigger offset. Now when I save my environment, though I can peek into memory and see the save worked, the board is never able to load these variables. I'm looking through the code but I can't find where U-Boot expects to find it's environment variables. As simple as this is this things seems to be way over complicated (of course it does service about 500 different boards so maybe it's unavoidable).

Can anyone tell where I can set U-Boot to grab it's environmental variables at a specific address? Any help would be appreciated

Re: MCV5485evb new Linux (2.6.25) BSP U-Boot environment variable problems

fsl_linux_spt — Wed, 29 Oct 2008 04:37:44 GMT

That is a good question. You should probably ask this quesiton on the u-boot mailing list.

http://www.denx.de/wiki/U-Boot

Re: MCV5485evb new Linux (2.6.25) BSP U-Boot environment variable problems

jkimble — Wed, 29 Oct 2008 07:16:00 GMT

I posted to this list because the specific issue I have is with the linker script that was implemented by whomever did the port of U-Boot for the Coldfire. Because the area where the environment variables are stored is based on a definition in the Linker script and that script is written expressly for Flash with 4K sectors it makes it particularly difficult to move to different flash (something I would think would be very common). This is something that should be as easy as changing a few #define's but instead, now requires a bit of analysis and some code changes.

It's certainly not monumental just a little... frustrating.