[U-Boot-Users] MMU and Linux kernel booting

[Wolfgang Denk]

In message <6.0.1.1.0.20041207154508.01efa490 at 192.168.2.1> you wrote:
> 
> I'm working with a custom hardware based on Cirrus Logic EP9315 processor.
> As the on-chip SDRAM controller is unable to map the memory in
> contiguous regions, I have to use the MMU to do that.

... if you need it. Maybe one bank of memory is  sufficient  for  the
operation of U-Boot?

> 1) In my understanding the function cleanup_before_linux 
> (cpu/arm920t/cpu.c) is supposed to
> perform this opearation but it does not. Is this the right place to turn 
> MMU off?

Yes.

> 2) The second questions refers to memory tags. They should describe _physical_
> mapping, right? If this is correct, the bd->bi_dram fields should be extended

Right.

> in order to describe both physical and virtual regions. Does it make sense?

Why would you need virtual addresses? U-Boot does not need these  for
operation, and Linux will not use these anyway.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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