Subject: Re: need advice regarding Au 1550 (MIPS) memory mapping
To: Andrey Petrov <petrov@netbsd.org>
From: Garrett D'Amore <garrett_damore@tadpole.com>
List: port-mips
Date: 09/30/2005 14:25:31
Andrey Petrov wrote:

>On Fri, Sep 30, 2005 at 09:08:07AM -0700, Garrett D'Amore wrote:
>  
>
>>Thanks for the advice.  It looks like I need to change the size of 
>>paddr_t, to accomodate a larger 36-bit value.  (The ARC port already 
>>does this, though I don't know why it needs 64-bit values here.)
>>
>>    
>>
>
>If you need 36-bit address (constant prefixes even) only for PCI access then
>likely you can work it out in your bus_.. functions. And that wouldn't justify
>larger paddr_t and new port, I understand temptation thou -)
>  
>
My concern was that when I was looking at the various logic surround 
setup of the mappings for the TLBs, paddr_t was used thru-out, and if I 
use those, then I need a larger paddr_t.

I'll look at the bus_XXX stuff to see if I can localize it and avoid a 
new port.

    -- Garrett

>  
>
>>I believe this means I have to create a new port, so that I can provide 
>>my own types.h to override the size of the paddr_t, just like the ARC 
>>port does.  I'm proposing that this port be called "aumips".
>>
>>Does anyone have any advice about the wisdom of this course of action?  
>>Any suggestions for better courses?
>>
>>   -- Garrett
>>
>>    
>>