TECHNICAL INFORMATION DOCUMENT

TITLE:              PTF227 - Pre-select auto-detection of FPU or the use 
                             of software emulation
DOCUMENT ID:        TID300184
DOCUMENT REVISION:  A
DATE:               23FEB95
ALERT STATUS:       Yellow
INFORMATION TYPE:   Symptom Solution
README FOR:         PTF227

PRODUCT and VERSION:
UnixWare 1.1

ABSTRACT:

This ptf provides the capability to pre-select auto-detection of 
Floating Point Unit or use of floating point emulator 
(performed by software) all the time. By selecting to use floating 
point emulator all the time, you can completely bypass the use of 
the hardware FPU.

SYMPTOM

NA

SOLUTION

Apply the ptf227 file.


Installation Instructions:

DATATYPE: datastream

1.  Download the ptf227 and ptf227.txt files to the /tmp directory  
    on your machine.

2.  Read the release notes contained in this file and follow the
    instuctions to add the packages to your system.

3.  Now become root, and add the package to your system using the following
    commands:

        $ su
        # pkgadd -d /tmp/ptf227 ptf227

Solution Specifics

General Description.
-------------------

These release notes acquaint you with the contents of UnixWare 
PTF227 - add capability to pre-select auto-detection of FPU or the use
of software emulation

UnixWare 1.1 automatically detects the presense of hardware Floating 
Point Unit and always employs the use of hardware FPU if available.  
This ptf adds capability to elect to use the floating point emulator 
(performed by software) regardless of the presense of hardware FPU.

New Features.
------------

Add capability to pre-select auto-detection of FPU or the use of software
emulation

Software Notes and Recommendations.
----------------------------------

The idtune command (under /etc/conf/bin) will be the interface for 
users to select the emulator or allow auto-detect of the floating 
point unit by the kernel.  

When the kernel tunable FPKIND is set to 0, the system will 
automatically detect the presense of hardware FPU and use hardware 
FPU if available. When the kernel tunable FPKIND is set to 1, software 
emulator will be used regardless of presense of hardware FPU.

After the installation of this PTF and subsequent reboot, FPKIND 
will be set to 1.  This will effectively bypass the use of hardware 
FPU (if it's present).  If this is not the behavior you desire, 
you should use idtune command to change it.  If you do want to 
change FPKIND tunable, please consult /etc/conf/mtune.d/svc for 
what the valid values are. The FPKIND definition in this file is 
inserted by this PTF.

THIS PTF WILL NOT WORK ON UW1.1 WITHOUT ANY UPDATE.
It is recommended that you apply PTF227 on systems running UW 1.1.3.

If you choose to remove (un-install) PTF227 and restore your system to its
original condition, please enter the following command:

     # pkgrm ptf227
     # remove FPKIND line from /etc/conf/cf.d/stune
     # shutdown and reboot

Hardware Notes and Recommendations.
----------------------------------

This PTF can be applied to a machine to allow pre-selection of either floating
point hardware or float point emulator.

Installation Instructions.
-------------------------

The PTF consists of 1 3.5 inch floppy.  Insert the floppy into the drive and,
while logged in as root, type

     pkgadd -d diskette1

and follow the instructions output by pkgadd.