Motorola PowerPC MBX

Overview

RedBoot uses the SMC1/COM1 serial port. The default serial port settings are 38400,8,N,1. Ethernet is also supported using the 10-base T connector.

Management of onboard flash is also supported. Two basic RedBoot configurations are supported:

Initial Installation Method

Device programmer is used to program the XU1 socketed flash part (AM29F040B) with the ROM version of RedBoot. - Use the on-board EPPC-Bug monitor to update RedBoot.

This assumes that you have EPPC-Bug in the on-board flash. This can be determined by setting up the board according to the following instructions and powering up the board.

The EPPC-Bug prompt should appear on the SMC1 connector at 9600 baud, 8N1.

  1. Set jumper 3 to 2-3 [allow XU1 flash to be programmed]

  2. Set jumper 4 to 2-3 [boot EPPC-Bug]

If it is available, program the flash by following these steps:

  1. Prepare EPPC-Bug for download:
    EPPC-Bug>lo 0
    At this point the monitor is ready for input. It will not return the prompt until the file has been downloaded.

  2. Use the terminal emulator's ASCII download feature (or a simple clipboard copy/paste operation) to download the redboot.ppcbug file.

    Note that on Linux, Minicom's ASCII download feature seems to be broken. A workaround is to load the file into emacs (or another editor) and copy the full contents to the clipboard. Then press the mouse paste-button (usually the middle one) over the Minicom window.

  3. Program the flash with the downloaded data:
    EPPC-Bug>pflash 40000 60000 fc000000

  4. Switch off the power, and change jumper 4 to 1-2. Turn on the power again. The board should now boot using the newly programmed RedBoot.

To install RedBoot on a target that already has eCos GDB stubs, download the RAM version of RedBoot and run it. Initialize the flash image directory:
RedBoot> fi init
Then download the ROM version of RedBoot and program it into flash:
RedBoot> load redboot_ROM.srec -b 0x80100000
RedBoot> fi cr RedBoot -f 0xFE000000 -b 0x00040000 -l 0x20000

Flash management

Updating the primary RedBoot image

To update the primary RedBoot images, follow the procedures detailed in the Section called Update the primary RedBoot flash image in Chapter 4, but the actual numbers used with the flags in the sample commands should be:
-f 0xfe000000
-b 0x50000
-l 0x20000

Updating the secondary RedBoot image

To update the secondary RedBoot images, follow the procedures detailed in the Section called Load and start a different version of RedBoot, running from RAM in Chapter 4, but the actual numbers used with the flags in the sample commands should be:
-f 0xfe020000
-b 0x20000
-r 0x20000
-l 0x20000

Special RedBoot Commands

None.

Memory Maps

Memory Maps RedBoot sets up the following memory map on the MBX board.
Physical Address Range Description
----------------------- -----------
0x00000000 - 0x003fffff DRAM
0xfa100000 - 0xfa100003 LEDs
0xfe000000 - 0xfe07ffff flash (AMD29F040B)
0xff000000 - 0xff0fffff MPC registers

Resource Usage

The flash based RedBoot image occupies flash addresses 0xfe000000 - 0xfe01ffff. RedBoot also reserves RAM (0x00000000 - 0x0001ffff) for RedBoot runtime uses. RAM based RedBoot configurations are designed to run from RAM at physical addresses 0x00020000 - 0x0004ffff. RAM physical addresses from 0x00050000 to the end of RAM are available for general use, such as a temporary scratchpad for downloaded images, before they are written to flash.

Rebuilding RedBoot

The instructions in Chapter 3 should be followed. The values for TARGET, ARCH_DIR and PLATFORM_DIR on this platform are “mbx”, “powerpc” and “mbx” respectively. Note that the configuration export files supplied in the hal/powerpc/mbx/VERSION/misc directory in the RedBoot source tree should be used.