@mijzelf
still try to find out why isp1 and 2big1 can boot larger kernels while they also seem to load the kernel at 0x400000, but they can load a 3MB standalone kernel without a problem so it seem u-boot is not present at location 0x200000 like on 5big1
I tried to figure out were u-boot is on these boards but I can not find a u-boot source code of lacie for these boards. But I found one where the edmin_v2 is incorporated. That board of the isp1 and 2big1 is almost same if I am informed correctly
This u-boot version does not set a TEXT_BASE value (address in ram where u-boot is loaded as far as I understood) in the config.mk file of the edmini_v2
Instead they set this
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# TEXT_BASE must equal the intended FLASH location of u-boot.
CONFIG_SYS_TEXT_BASE = 0xfff90000
If you convert this hex number to decimal then you get a number that is much bigger than the RAM size of theses boards, so it can not be the address where it is loaded in RAM. But what does is the real meaning then ?
I googled a while on it but can find a clear answer what this number means, some mention it is the same as TEXT_BASE
But that number is larger then the physical RAM size in bytes.
So I guess u-boot uses virtual memory addresses. Then the max is 0xffffffff and it is mapped to physical memory by the kernel using paging and other complicated stuff.
--edit I checked on the isp1 and indeed u-boot is at (virtual) address 0xfff90000 so near the end of the RAM I suppose. Although I have no idea were it is really stored in physical ram which is only 64 MB, while virtual is 4 GB).
Anyhow no problems with a somewhat bigger kernel on the edmini_v2, isp1 and 2big1 as u-boot is not in the way :-D
(maybe it are stupid question but I try to learn and understand)