[ECOS] again ROMRAM startup on SA1100

[Gary Thomas]

On 11-Jun-2001 Andrew Lunn wrote:
>  > The b __new_pc is important. This is where is jumps from ROM to
>> > RAM. Do you have an equivelent somewhere? You have to be carefull
>> > about the address you are branching to. You dont want to make a
>> > relative jump of 1 instruction, since you still end up on ROM. You
>> > have to make big jump down into RAM. I just copied this code from Dave
>> > Airlie.
>> 
>> I believe that it happens implicitly when the MMU gets turned on - pretty slick.
> 
> ?
> 
> Could you expand on that. I don't see how this works.

It probably depends on which platform he's using.  On the EBSA, I'm not sure
that it will work because the setup of the MMU is way too late. On the SA11x0
though, the MMU is setup in PLATFORM_SETUP and the last step is to enable the
MMU, including changing the address space which is just like your code.

Look at hal/arm/sa11x0/ipaq/current/include/hal_platform_setup.h for an example.