[U-Boot-Users] Protect an area in RAM

[Wolfgang Denk]

In message <DC6F86A94046A64094043D44A3A708F7A14AFA at sestoex02.enea.se> you wrote:
> 
> Thanks for you answer! I have found that one, but I need to be able to
> specify exactly what memory range that shall be protected. I did find

The pRAM area is always at the very upper end of the RAM. If you want
to pass it unchanged between U-Boot and an OS and back there are  not
many options.

> the CONFIG_PRAM-parameter but I did not figure out how to tell u-boot
> exactly what range not to whipe-out. Such as do not destroy
> 0x1000-0x2000. Also the solution that I would like to find/create is to
> have the possibility to set a protect area using a system parameter in
> order to be able to change the protection zone without recompilation.
> Would that be a good feature?

I have never seen a need for this, and, given the things you have  to
keep  in  mind  (memory  resizing  coee  after  reset, eventually ECC
initialization, making sure that both U-Boot  and  the  OS  agree  on
exactly  the  same  memory  area, etc., I don;t see an easy way to do
what you want, either.

Why do you have to use a specific memory range? It sounds as if  this
was  a  restriction  that  comes  from  the OS - how about fixing the
problem there?

Best regards,

Wolfgang Denk

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