Extended Addressing Mode

[Kumar Gala]

On Oct 22, 2008, at 7:59 AM, Régis Odeyé wrote:

> Kumar Gala wrote:
>>
>> On Oct 22, 2008, at 3:59 AM, Régis Odeyé wrote:
>>
>>> Hello Everyone,
>>> I'm looking for some information about the Extended Addressing  
>>> Mode (XAEN bit of HID0 register) of PPC32 support in Linux.
>>> I do not see anything in the main kernel tree but there may be  
>>> some patches available ?
>>> Any information will be appreciate.
>>> Regards.
>>
>> There are patches from Becky Bruce that are going into 2.6.28.   
>> What are you needing >32-bit for?  There are some SW IO MMU changes  
>> that are still pending to complete this work.
>>
>> - k
> We are developing a board based on Freescale 8641D which can get 4GB  
> of ram. So I need 4GB+IOs (~1GB) of physical addressing space.
> My plan is to put a part of this ram above of 4GB to keep accesses  
> to the IOs below the 4GB limit. It means non-contiguous ram  
> addressing and XAEN features to be working.

So we have XAEN support in the tree.. however non-contiguous is  
something you'll have to work on yourself.  Patches are welcome for this

>
> Where can I glance through Becky patches ?

This is the bulk:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=4ee7084eb11e00eb02dc8435fd18273a61ffa9bf

- k