Motorola MVME3100 manual Firmware Scan for Boot Image, Address Usage

Chapter 3 MOTLoad Firmware

Firmware Scan for Boot Image

The scan is performed by examining each 1MB boundary for a defined set of flags that identify the image as being Power On Self Test (POST), USER, or Alternate MOTLoad. POST is a user- developed Power On Self Test that would perform a set of diagnostics and then return to the bootloader image. USER would be a boot image, such as the VxWorks bootrom, which would perform board initialization. A bootable VxWorks kernel would also be a USER image. Boot images are not restricted to being MB or less in size; however, they must begin on a 1MB boundary within the 8MB of the scanned flash bank. The Flash Bank Structure is shown below:

Address	Usage
0xFFF00000 to 0xFFFFFFFF	Boot block. Recovery code
0xFFE00000 to 0XFFFFFFFF	Reserved.
	(MOTLoad update image)
0xFFD00000 to 0xFFDFFFFF	First possible alternate image
	(Bank B / Bank A actual)
0xFFC00000 to 0xFFCFFFFF	Second possible alternate image
	(Bank B / Bank A actual)
....	Alternate boot images
0xFF899999 to 0xFF8FFFFF	Bottom of Flash
	(Flash size varies per product)

The scan is performed downwards beginning at the location of the first possible alternate image and searches first for POST, then USER, and finally Alternate MOTLoad images. In the case of multiple images of the same type, control is passed to the first image encountered in the scan.

Safe Start, whether invoked by hitting ESC on the console within the first five seconds following power-on reset or by setting the Safe Start jumper, interrupts the scan process. The user may then display the available boot images and select the desired image. The feature is provided to enable recovery in cases when the programmed Alternate Boot Image is no longer desired. The following output is an example of an interactive Safe Start:

ABCDEInteractive Boot Mode Entered boot> ?

Interactive boot commands:

’d’:show directory of alternate boot images ’c’:continue with normal startup

’q’:quit without executing any alternate boot image

’r [address]’:execute specified (or default) alternate image ’p [address]’:execute specified (or default) POST image ’?’:this help screen

’h’:this help screen boot> d

Addr FFE00000 Size 00100000 Flags 00000003 Name: MOTLoad

Addr FFD00000 Size 00100000 Flags 00000003 Name: MOTLoad boot> c NOPQRSTUVabcdefghijk#lmn3opqrsstuvxyzaWXZ

Copyright Motorola Inc. 1999-2004, All Rights Reserved

MOTLoad RTOS Version 2.0, PAL Version 0.b EA02

30MVME3100 Single-Board Computer Installation and Use (V3100A/IH1)