RedBoot supports the serial port labelled +P2 on the board. The default serial port settings are 57600,8,N,1. RedBoot +also supports flash management on the Excalibur.
The following RedBoot configurations are supported: + +
| Configuration | Mode | Description | File |
|---|---|---|---|
| ROMRAM | [ROMRAM] | RedBoot running from RAM, but contained in the + board's flash boot sector. | redboot_ROMRAM.ecm |
| RAM | [RAM] | RedBoot running from RAM with RedBoot in the + flash boot sector. | redboot_RAM.ecm |
| REDBOOT | [ROMRAM] | RedBoot running from top of RAM, but contained in + the board's flash boot sector. | redboot_REDBOOT.ecm |
NOTE: RedBoot is currently hardwired to use a 128MB SDRAM SIMM module.
A Windows utility +(exc_flash_programmer.exe) is used to +program flash using the ByteBlasterMV JTAG unit. +See board documentation for details on +in situ flash programming.
For ethernet to work (under Linux) the following jumper +settings should be used on a REV 2 board:
SW2-9 : OFF
+U179 : 2-3
+JP14-18 : OPEN
+JP40-41 : 2-3
+JP51-55 : 2-3
The ROMRAM and REDBOOT configurations supported on this platform +differ only in the memory layout (ROMRAM configuration runs RedBoot from +0x00008000 while REDBOOT configuration runs RedBoot from 0x07f80000). The +REDBOOT configuration allows applications to be loaded and run from +address 0x00008000.
The exec command which allows the loading +and execution of Linux kernels, +is supported for this board (see the Section called Executing Programs from RedBoot in Chapter 2). The exec parameters used for the Excalibur are:
Location Linux kernel was loaded to
Length of kernel
Parameters passed to kernel
'initrd' ramdisk location
Length of initrd ramdisk
The parameters for kernel image base and size are automatically +set after a load operation. So one way of starting the kernel would +be: + +
RedBoot> load -r -b 0x100000 zImage +Raw file loaded 0x00100000-0x001a3d6c +RedBoot> exec -c "console=ttyUA0,57600" +Using base address 0x00100000 and length 0x000a3d6c +Uncompressing Linux..... |
RedBoot> exec -b 0x40400000 -l 0xc0000 -c "console=ttyUA0,57600" +Uncompressing Linux..... |
The MMU page tables are located at 0x4000.
NOTE: The virtual memory maps in this section use a C and B column to indicate +whether or not the region is cached (C) or buffered (B).
Physical Address Range Description +----------------------- ---------------------------------- +0x00000000 - 0x07ffffff SDRAM +0x08000000 - 0x0805ffff On-chip SRAM +0x40000000 - 0x40ffffff Flash +0x7fffc000 - 0x7fffffff I/O registers +0x80000000 - 0x8001ffff PLD + +Virtual Address Range C B Description +----------------------- - - ---------------------------------- +0x00000000 - 0x07ffffff Y Y SDRAM +0x08000000 - 0x0805ffff Y Y On-chip SRAM +0x40000000 - 0x403fffff N Y Flash +0x7fffc000 - 0x7fffffff N N I/O registers +0x80000000 - 0x8001ffff N N PLD |
These shell variables provide the platform-specific information +needed for building RedBoot according to the procedure described in +Chapter 3: +
export TARGET=excalibur_arm9 +export ARCH_DIR=arm +export PLATFORM_DIR=arm9/excalibur |
The names of configuration files are listed above with the +description of the associated modes.