We have a new P1022 board, and we would like to run u-boot out of ram (DDR) to
debug the flash subsystem. We're using QorIQ-SDK-V1.6 to build.
I've followed the document in doc/README.ramboot.ramboot-ppc85xx, so
I've got a u-boot.bin linked what seems to be the right way, but I'm having
troouble getting it to run. I can load it into ram with CW + USB Tap,
and start and step through the code, but it won't run far.
The primary problem is I'm uncertain of the entry point. When I start
at _start_e500 the init process seems to overwrite the MMU and LAW
buffers supporting access to DDR, and things stop. Similar problems
starting at _start_cont. If I setup stack and start from board_init_f, the
there are things not configured, i.e. global data.
Is there a good way to do this without modifying too much code?
Thanks in Advance,
-- cary
Take a look on this application note, CodeWarrior U-Boot Debugging.
Adrian
This helped a lot.
I also found out that I had to have my setup script use L2TLB 0, LAW 0, and CS0
to setup ddr. If I used different entries, u-boot would clear them in the startup
process and then fail since it had unmapped it's own code. And not move
CCSRBAR.
-- cary