Subject: Re: Porting to IBM Risc 6000
To: Matt Thomas <matt@3am-software.com>
From: David Edelsohn <dje@watson.ibm.com>
List: port-powerpc
Date: 08/09/2002 10:39:12
>>>>> Matt Thomas writes:

Matt> Does Power3 follow the OEA 64-bit manual for memory management?  Does it
Matt> do the 32-bit and 64-bit bridges?

	Power3 supports the OEA and includes the 64-bit bridge mode
instructions. 

Matt> If so, it seems the only significant difference is the replacement
Matt> of the segment register with the segment descriptor elements and the
Matt> Address Space Register.   I assume I need to do a "slbia" when changing
Matt> the ASR register (aka process switching).  Or just update the active
Matt> SDE's on a stack switch (which would prevent having to flush the kernel
Matt> SDE entries from the SLB).

	64-bit bridge mode includes backward compatibility for segment
registers (suitably expanded), so one does not need to deal with the
entire segment descriptor infrastructure and the lack of BATs.

David