issue at the beginning of kernel booting

Sauce.Cheng chmhou at sina.com
Wed Apr 8 00:39:44 EST 2009


thanks Scott 's following

> I don't quite follow the above, but what I meant is that you need to
> put a mapping in place that covers your LED I/O once you have the MMU on.
> Any mappings that U-boot made will be gone at that point.

i am sorry for my poor expression. i think i have got your meaning about
that.
the suggestion from others that the situation that external access will be
disabled at early booting time. i guess that means like yours, sometimes I/O
disabled due to cache operating or something.

certainly, if i have to turn LEDs at booting time, the way your said is the
best. but i supposed i could operate LEDs after early booting time. 

>> i tried 
>> CONFIG_PPC_EARLY_DEBUG_CPM=y 
>> CONFIG_PPC_EARLY_DEBUG_CPM_ADDR=0xf00000008	
>> how can i make sure CPM_ADDR, 0xf0000008 is default value 

> Look at the u-boot source, or dump the memory and see if it looks like a
> ring buffer.

sorry, i mean that CPM_ADDR is address of what? address of CPM registers or
something?

> This is a dts-v0 tree, which implies it's fairly old.
dose later dts be used in corresponding kernel version ?

i guess i must read "booting-without-of.txt". many of contents in dts i have
no idea.

in addition, there is one more question. 
my RAM size is 32MBytes, my "vmlinux" size is 30MBytes, "vmlinux.o" size is
58MBytes. so , will there be something wrong at uncompressing time ?

Sauce
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