Noah yan wrote:
> Thanks for your answering.
>  
> You mention that BAT is only used in kernel and The addresses mapped by
> BATs and those by PTEs don't overlap, do you imply that the seg/page
> tables are not setup for kernel?

The kernel uses both the BAT registers and page tables.

> Is netbsd really use the segment MMU of the powerpc, I have an
> impression that most kernel (such as linux) only use the page MMU?

Yes it does.


-- 
Matt Thomas                     email: matt@3am-software.com
3am Software Foundry              www: http://3am-software.com/bio/matt/
Cupertino, CA              disclaimer: I avow all knowledge of this message.