Date: Sat, 16 Sep 1995 10:01:57 -0700
From: ron@apple.com (Ron Hochsprung)
Subject: Item #289: Device Ext: add support for multi-initiator SCSI


P1275 Openboot Working Group Proposal -- Proposal #:289 Ver 1

Title:          Support for multi-initiator SCSI

Author:         Ron Hochsprung

Date:           Sept 16, 1995

Ed/Tech:        Technical

Synopsis:       Add support for multi-initiator SCSI systems

Doc & Version:  Device Support Extensions to Open Firmware

Problem:

The existing SCSI "binding" does not have a way of specifying the
initiator ID to be used for SCSI transactions.  This is a problem
when booting on systems that are using a shared SCSI connection with
another system.

Proposal:

Add to Device Support Extension to Open Firmware:

Section 9.1     Properties for Bus Nodes

"initiator-id"

        prop-name:  Standard property indicating the initiator-id to be
        used for SCSI transfers by this controller.

        prop-encoded-array:  An integer, encoded as with *endode-int*, that
        specifies the value of the initiator-id for subsequent transfers
        by this controller.  The value is in the range 0..7 if "wide" is
        not present or 0..15 if "wide" is present.  The initial value
        of the property is implementation dependent;  the maximum possible
        value (i.e., 7 or 15) is recommended.

        If this property is not present, it indicates that this bus node
        does not support the initiator-id facility.

Section 9.2     Methods for Bus Nodes

open     ( -- true )

        The *open* method for a bus node supporting this extension shall
        parse its argument string (i.e., my-args) to update its value of
        "intitiator-id".  The value to be parsed must be a single decimal
        number in the range 0..7 (or, 0..15 if "wide" is present). If the
        argument is missing, no change to "initiator- id" is made.



[ P1275 Item #289 -- Received: Sat Sep 16 10:04:36 PDT 1995 ]