+------------------------------------------------+
|  $TOPDIR/arch/mips/galileo/compressed/README   |
|                                                |
|  By RidgeRun Inc,                              |
|  Aug, 2000                                     |
+------------------------------------------------+

Description:
============
  It is intended that this makefile be wired in to run as
  part of a top level linux build. For example, at the
  time of this writing, if the user types "make gboot" at
  the top level then in addition to building vmlinux the
  build system's makefiles will descend into this
  directory and build the "all:" target of this
  Makefile. This will have the result of compressing the
  vmlinux system and producing four separate systems. The
  following snippet is pulled from this directory's
  Makefile and describes each system.

  Four systems are availalbe for download to the EVB64120A
  board.

   1. - ramsys - 
      To be loaded into ram then run. When run
      it decompresses the "vmlinux" kernel housed in its internal
      data structures and then jumps to the image which
      results in a linux kernel boot.

   2. - flashsys - 
      To be loaded into ram so that it can be
      burned into the onboard flash. Then the board jumpers
      can be switched so that the next power cycle caused
      the system in flash to run which then proceeds as
      described by #1 above.
      Note: burner.srec is the utility that will allow
      the user to get this image into flash.

   3. - flashsys2 - 
      To be loaded into ram so that it can be
      burned into the onboard flash. Then on each power
      cycle when the standard PMON prompt is presented 
      the user can type `call 0xbf000000` to invoke
      the system in flash which then proceeds as
      described by #1 above.
      Note: burner.srec is the utility that will allow
      the user to get this image into flash.

   4. - burner.srec -
      Related to #2 and #3 above.

Example: Running from Ram
==========================

  In this scenario the compressed system is downloaded
  into ram and run directly from there. No flash is involved 
  in this scenario. Naturally, the download must be repeated 
  on every power cycle.

  1. At the PMON prompt type `load`
  2. Assuming you have your host connected to /dev/ttyS0
     type the following command in a host shell window.
     `cat ramsys.srec > /dev/ttyS0`
  3. When the download completes type the following
     at the PMON prompt: `g`


Example: Running from flash: Scenario #1
========================================

  In this scenario vmlinux runs out of flash code
  automatically on every power up. This means that 
  standard PMON code (of eprom) never runs.

  1. Place the boot jumpers in the Boot-from-eprom
     state. This is the normal state and how the jumpers
     are found when booting PMON.

     Jumper settings. J11 - Removed
                      J20 - Moved from the 1&2 position to 
                            the 2&3 position instead

  2. Use PMON to "load" the burner.srec image and then
     run it. This utility will prompt you to download
     the image that you want burned into the flash
     part.

  3. Send the flashsys.srec image to the running burner
     utility. The utililty will indicate when the burn
     process has completed.

  4. Now switch off power and change the jumpers to 
     the boot-from-flash position. The next power cycle
     will run the flash based system automatically.

     Jumper settings. J11 - Added.
                      J20 - Moved from the 2&3 position to 
                            the 1&2 position instead

Example: Running from flash: Scenario #2
========================================

  In this scenario vmlinux runs out of flash only if the
  PMON user decides to jump there by issuing a command to
  PMON. Every power cycle would continue to bring up PMON
  and a user will have to reissue the jump command to
  force control transfer to the flash system.

  1. Insure that the boot jumpers are in the Boot-from-eprom
     state. This is the normal state and how the jumpers
     are found when booting PMON.

     Jumper settings. J11 - Removed
                      J20 - Moved from the 1&2 position to 
                            the 2&3 position instead

  2. Use PMON to "load" the burner.srec image and then
     run it. This utility will prompt you to download
     the image that you want burned into the flash
     part.

  3. Send the flashsys2.srec image to the running burner
     utility. The utililty will indicate when the burn
     process has completed.

  4. Now that the image is in flash the user can invoke
     the following PMON command whenever a vmlinux
     boot is desired:

     call 0xbf000000

