
13 Jun
2011
13 Jun
'11
3:09 p.m.
Hi Christopher,
What is the CONFIG_SYS_TEXT_BASE variable and how can I figure out what it should be?
U-boot is typically stored in flash and one of the first things it does when executed is relocate to ram. CONFIG_SYS_TEXT_BASE is the relocation address. Typically, u-boot global data, heap and then stack is stored just below this.
Since u-boot is used to load some other program like the kernel, you need the u-boot relocation address to be out of the way of this. So, for the boards I have seen (not arm), CONFIG_SYS_TEXT_BASE is set to the top of ram - 256KB, i.e. enough room for the u-boot image.
I am sure more experienced u-boot developers will correct me if I am wrong :)
Regards Phil