[U-Boot-Users] AT91RM9200 boot.bin interaction with u-boot and SDRAM

[Craig Robinson]

Dear Ulf, 

A while back
(http://www.nabble.com/at91rm9200---silent-console-tf4418118.html#a12631849)
you pointed me at the atmel patched source for u-boot 1.2.0. I have compiled
and run this on the EK with out problems. Thank-you. 

However, I now come to getting u-boot to function on our EK based hardware.
Our new board has AT49BV642D flash and I have added support to the code for
this part (still compiles and runs on the EK). Aside from a total lack of
Ethernet support, the main difference between our board and the EK is the
size of the SDRAM. We use half that on the EK (16Meg rather than 32Meg). So,
reading the source code for both u-boot and boot.bin, I'm thinking that we
need to change some things to take into account the change in SDRAM. What I
think I need to alter is: 

boot.bin - 

main.c 
#define DST 0x21f00000 to 0x20f00000
entry.S
redefine STACK to be 0x21000000 not 0x22000000

u-boot - 

change TEXT_BASE to 0x20f00000
redefine PHYS_SDRAM_SIZE to 0x1000000 in <board>.h

Is this correct and have I missed anything? 

Also, is it broadly correct to say that boot.bin does the following: 

1. low level init
2. uncompress a gzipped file from SRC in parallel flash and put it in SDRAM
at DST
3. jump to unzipped file at DST.

If this is the case, then do we need to also ensure that
CONFIG_SKIP_RELOCATE_UBOOT is defined? Is there a point to this aside from
saving space in flash? 

Many thanks in advance.
Craig Robinson.

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