Freescale i.MX53-QSB (loco,START) board and fw_env.config

[Ludigel]

I am using the iMX53-QSB board from Freescale, which is similar to the LOCO or START board, but does not have NAND flash memory.

I have successfully built the u-boot/tools/env tools, but do not know what to fill into the fw_env.config file.

I do not have the /dev/mtd0 or /dev/mtd1 or /dev/mtd2 devices on my filesystem (which is based on the standard filesystem which came with the package) and am assuming that is because there is no NAND memory.

However my u-boot is working, booting from SD-card and saving its environment, I am assuming on the SD-card itself.

Anybody knowing the settings or how to get them?

Thank you in advance.

[Ludigel]

Seems the env tool cannot support SD-card. As the board does not have NAND, U-boot has to write its config onto the SD-card. Anybody can think of a way how U-boot can access the rootfs easily? I need it to write one of its environment values into the Linux rootfs.

[xenoxaos]

I'm not sure if fw_setenv/readenv will work with u-boot environments on an SD card. I would probably start out by dumping the first meg or so of the SD card and opening that up in a hex editor and poke around for the u-boot environment area. Then try feeding that location to fw_env.config, making sure to alter the device as well, /dev/mmcblk0 or whatever the base device for the SD is. Also, make sure to do a environment READ to test the location....don't try a write until you know it works.

[Ludigel]

Thank you, that is a good hint. I probably try that or I just wait until we get the final reference board which will be used for our production, as that has NAND flash which would be supported by fw_readenv. Still having a nice demo in advance would be nice.

BTW the whole thing is for a security feature called "boot counting", so U-boot and Linux should both count their boot number and an alarm should be raised if not the same...

[WarheadsSE]

I'm afraid with some modification, this would be pointless. In either direction, the numbers are arbitrary to either fake, or simply alter.