Browse Prior Art Database

Reference Partition Location and Manipulation Utility

IP.com Disclosure Number: IPCOM000106160D
Original Publication Date: 1993-Oct-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 4 page(s) / 151K

Publishing Venue

IBM

Related People

Dunham, SN: AUTHOR [+2]

Abstract

Disclosed is a utility for searching file units attached to a system by means of a SCSI (Small Computer System Interface) interface, to find IML images, where microcode for the IML (Initial Microcode Load) function is stored. The file units which may be searched in this way include hard files and optical drives, in both fixed and removable configurations. For each such device, this utility displays the PUN and LUN (Physical Unit Number and Logical Unit Numbers) numbers identifying the location of the device on the SCSI interface, and whether an IML image is found. If the device contains an IML image, the utility further displays the models and submodels of the planar (system) board and processor cards supported.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 42% of the total text.

Reference Partition Location and Manipulation Utility

      Disclosed is a utility for searching file units attached to a
system by means of a SCSI (Small Computer System Interface)
interface, to find IML images, where microcode for the IML (Initial
Microcode Load) function is stored.  The file units which may be
searched in this way include hard files and optical drives, in both
fixed and removable configurations.  For each such device, this
utility displays the PUN and LUN (Physical Unit Number and Logical
Unit Numbers) numbers identifying the location of the device on the
SCSI interface, and whether an IML image is found.  If the device
contains an IML image, the utility further displays the models and
submodels of the planar (system) board and processor cards supported.

      Upon power up, the POST (Power-On Self Test) and BIOS (Basic
Input/Output System) code of a system executes out of EPROM (Erasable
Programmable Read-Only Memory) until the magnetic media becomes avail
able.  When this media becomes available, the IML function is used to
load the remaining POST and BIOS code into certain RAM (Random Access
Memory) segments of the system.  In this process, the code from EPROM
searches all SCSI hard files for the latest IML image appropriate for
the system.

      The Reference Partition is a portion of the hardfile of a
system in which POST and BIOS code is stored for loading during the
IML process, along with other code, such as Set up and various types
of diagnostics.  The Reference Partition is located in the
addressable space of a file unit at the end with the highest
addresses.  During normal operation of the system, the SCSI adapter
interface protects the Reference Partition from being written.

      The Search IML routine allows IML images to exist on multiple
hard files, on removable hard files, and on read/write optical files,
whether fixed or removable.  Multiple machines may be twin tailed
(connected to the same SCSI bus), accessing the same files having
Reference Partitions.

      The Reference Partition Location and Manipulation Utility
provides an ability to display information stored in the Reference
Partition and to replicate the pattern.  To assist in testing the
Search IML routine, this utility supports zeroing a Reference
Partition, copying a Reference Partition, or walking a Reference

Partition.  During the copying process, the utility adjusts media
pointers in the IML image, accounting for differences in media size.
The walking process consists of copying the Reference Partition that
was the IML source to the next device index, and then zeroing the
Partition on the current IML source.

      Devices are addressed by position in a table built using the
search algorithm also used by the Search IML routine.  Devices are
numbered from the highest PUN value on the SCSI adapter in the lowest
numbered bus slot, to the lowest PUN value on the adapter in the
highest numbered bus slot. ...