From: Michael Segapeli <mikes@austin.ibm.com>
Subject: Item #276: PowerPC binding V1.3, Open Firmware's use of BATs
Date: Fri, 07 Jul 95 15:15:07 -0600


P1275 Open Firmware Working Group Proposal -- Proposal #276 Ver 1

Title:          Clarify rules on BAT usage

Author:         Mike Segapeli

Date:           July 7, 1995

Ed/Tech:        Technical

Synopsis:       Remove restriction on Open Firmware's use of BATs

Doc & Version:  PowerPC Binding Version 1.3

Problem:        The rule restricting BAT usage on Open Firmware's part
		      (page 6, line 32) seems to confilct with the text of
		      the fourth bullet (line 35/36) which specifies how control 
                of all address translation hardware is transferred from
		      Open Firmware to the client.

Proposal:       

On page 6 line 32 (Ver 1.3) remove the following text:

   " - shall not use BATs during Client or User Interface
       operations."

Also, this section (1.6 Virtual Mode Rules) does not really specify (it
does seem to imply) who can touch address translation hardware
before the "set-callback".  Therefore, I propose to add the following
paragraph after the paragraph that starts on  page 6, line 44:

  "[bullet] A client program shall not manipulate any address translation
   hardware until it has issued a "set-callback" to install the "translate" 
   callback."


[ P1275 Item #276 -- Received: Fri Jul  7 13:18:14 PDT 1995 ]