Global Data area

Greetings

I'm just getting porting U-boot to (yet another) board but I'm not sure I understand how the Global Data area works.

When still running from Flash, the Init_sequence list of functions is called and several of them write to the gd (clock rate & baudrate for example) but I thought this structure was in Flash. Is it in fact in RAM (i.e. the internal dual port RAM thats used during boot) in which case where is it initialised (or is it done on the fly?)

I was expecting something built from the #defines in the board specific config file but not found it so far!!

Just that I'm getting hung up in the first serial TX (display_info) and I'm guessing that the clocks to the SMC block are not getting set up correctly.

Robin Gilks
Senior Design Engineer              Phone: (+64)(3) 357 1569
Tait Electronics                          Fax  :  (+64)(3) 359 4632
PO Box 1645 Christchurch        Email : robin.gilks at tait.co.nz
New Zealand

Which part of section "Initial Stack, Global Data" did you fail to understand?

And which CPU are we speaking about?

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
When a man sits with a pretty girl for  an  hour,  it  seems  like  a
minute.  But let him sit on a hot stove for a minute -- and it's lon-
ger than any hour. That's relativity.              -- Albert Einstein