Hello Wolfgang,
El Tue, Dec 08, 2009 at 12:51:47AM +0100 Wolfgang Denk ha dit:
U-Boot uses assembler only when ther eis no reasonable way to implement the code in C, and I don't see any such justification here. Please rewrite all this in C.
i'm just starting to get my feet wet with low level initialization and supposed sdram setup is always done in assembler.
There is no reason for assembly. We almost always do this in C.
i am starting to look at this issue and it seems i need some more guidance:
before relocating U-Boot to RAM for ARM920T processors a jump to the label *lowlevel_init* is performed, where RAM timings are supposed to be set up. in the patch i sent these operations are performed in assembly and you asked me to rewrite them in C.
i'm relativly new to low-level setup, so i apologize if the following question sounds plain stupid to you: is C really available at this point? if my interpretation of the code in cpu/arm920t/start.S is correct, C code starts at start_armboot, after relocation of U-Boot. and after that point i'd think it's to late to change RAM timings as U-Boot is running from RAM.
could you please give some advice to clear my confusion and maybe provide a pointer to a board/cpu which handles low-level setup in the intended way?
thanks