Bios for EBSA-285
-----------------

Copyright (C) 1998-1999 Russell King.

Copyright: GPL

Various bits'n'pieces taken from the Linux kernel


This is a multi-function kernel loader for the EBSA-285 evaluation board and
other DEC21285-based systems.  It is capable of loading a kernel over the
locally attached network using BOOTP and TFTP protocols.  Future enhancements
will allow loading of the kernel off a hard drive.

Supported devices
-----------------

Currently, bios has been tested with:

- 3com 3c59x network card
- S3 Trio64V2+ VGA card
- Promise UDMA IDE card
   (Only tested on a Seagate ST35651A UDMA2 drive)

Compilation
-----------

	*** THIS MUST BE COMPILED WITH AN A.OUT COMPILER ***
(alternatively, patch 'mkaif' and send patches to rmk@arm.uk.linux.org)

To compile, edit the top-level make file and alter:

1) TEXTADDR to be an address in the EBSA-285's flash.
   The address is dependent on the bank number, and is calculated
   as follows:

	TEXTADDR = 0x410000a0 + bank * 0x00040000

2) LINUXPATH to be the path to your ARM Linux 2.2 sources.  (I don't think
   that this is still required).

3) CROSS_COMPILE to be the prefix to use for the ARM toolchain

Next, type "make dep".  This will generate the required dependency
information.

Then, type "make".  This will produce two binary files:
 - bios.a.out or
 - bios.elf   - an unstripped file
 - bios       - the AIF image to program into the flash.

Configuration
-------------

The loader uses jumper J17 pins 11-12 to configure the root device that
the kernel will use.  With the jumper fitted, it will boot from the
/dev/hda3 device.  With it removed, the kernel will try to get an NFS root
filesystem.

Future
------

If you think the BIOS could do with some extra features, you are welcome
to generate some code for it, and send it to me at <rmk@arm.linux.org.uk>.

Ideas thus far:
 * Fuller VT100 terminal emulation on VGA (but only as far as the
    features of the BIOS needs).
 * Textual configuration (eg, windowed)
 * Use on-board flash to store configuration information
 * Pre-compile time configuration of facilities
    (maybe borrow the Linux configuration system)?

As always:
 * More ethernet cards supported
 * More VGA cards support
 * Other IDE chipsets
