README for Prisma kernel source diffs

This archive should be unpacked into your Minix kernel source directory.
The contents should be:

  tools.m68k/		subdirectory containing the tools to build
			the kernel
  diffs-280499/		subdirectory containg the patches for the
			includes, library and kernel sources.
  diffs-280499/README.Prisma	This file.

The diffs were made against the distribution Minix 2.0.2 kernel
*WITH* the select() patches applied. The select patches should
be obtainable from the same place you found these diffs or you
could try:

  http://dspace.dial.pipex.com/town/way/fr30/

The diffs represent a snapshot of my Prisma kernel as of April 1999.
This is still undergoing development and contains some features which
are not implemented or only partially implemented. However, it does
boot, the network interface works and it will run commands.

The use of subdirectories for the m68k and Prisma specific code is
a late change and is part of an attempt to re-structure the source
tree to allow both i386 and m68k kernels to be built from the same
sources. This is experimental and likely to be changed in future
releases.


Installation
------------
The patches are intended to be applied to each of the main subdirectories
using 'patch -p0'. Your 'patch' program must be capable of creating
new files and subdirectories as required. The patches produce a kernel
suitable to run on an ISICAD Prisma diskless workstation, model 700,
with a 68020 processor *ONLY*, nothing else. The hope is that others
will use these patches as a starting point to port Minix to other m68k
based systems.

Apply the patches as follows:

  in usr/include:	patch -p0 < incl.diff
  in usr/src/lib:	patch -p0 < lib.diff
  in usr/src/fs:	patch < fs.diff
  in usr/src/mm:	patch < mm.diff
  in usr/src/inet:	patch -p0 < inet.diff
  in usr/src/kernel:	patch -p0 < kernel.diff

The file 'common.mk' defines the compiler options for all
the kernel components. It should be edited to reflect your
development environment then copied to the parent directory of
the kernel, fs, mm and inet sources. There is another common.mk
file in src/lib which defines the options for building the 
libraries.

The Makefile in tools.m68k is the master Makefile for the kernel.
The libraries are built using 'make -f Makefile.m68k all' in
src/lib.


The Prisma ram-disk
-------------------
The Prisma is diskless so I have modified the filesystem code to
recognise a ramdisk image attached to the end of the kernel. This
gives me a basic root filesystem and enough commands to login and
test applications. The ramdisk is currently around 980 Kbytes and
is available separately from the web site mentioned above. You
do not need it unless you have a Prisma.


Compiling the user commands for m68k
------------------------------------
I have only built a subset of the commands myself, enough to test
out the kernel and networking. If you have a compiler that can
build the kernel then it will also compile the commands. Just
modify the Makefiles to along similar lines to those used in
the kernel.


George Harvey
fr30@dial.pipex.com
28th April 1999