Programming RedBoot

There are several ways to program the target flash:

	Note
	RedBoot is configured by default with both network interfaces active, and waits for both of them to come up before allowing user interaction. This may take up to a minute if either are not connected to a network. It is recommended to connect both interfaces.

Initializing RedBoot Flash Configuration

When RedBoot is loaded into the on-chip flash, it maintains a number of persistent settings in the configuration store on the NAND flash. The flash configuration area needs to be initialized with the following commands.

RedBoot> fconfig -i
Initialize non-volatile configuration - continue (y/n)? y
Run script at boot: false
Use BOOTP for network configuration: true
Default server IP address:
DNS domain name:
DNS server IP address:
Network hardware address [MAC] for eth0: 0x0E:0x00:0x00:0xEA:0x18:0xF0
Network hardware address [MAC] for eth1: 0x0E:0x00:0x00:0xEA:0x18:0xF0
GDB connection port: 9000
Force console for special debug messages: false
Network debug at boot time: false
Default network device: at91_eth1
Update RedBoot non-volatile configuration - continue (y/n)? y
... Erase from 0x00000000-0x00000fff: .
... Program from 0x2fdff000-0x2fe00000 to 0x00000000: .
RedBoot>

Rebuilding RedBoot

	Note
	Pre-built RedBoot binary images are supplied with the eCos release in the loaders sub-directory.

RedBoot will normally be a ROMRAM startup, since it will be loaded via the second-level bootloader, or loaded directly using a hardware JTAG debugger, into the DDR2-SDRAM memory for execution.

The following example illustrates the command-line steps needed to configure and build a ROMRAM RedBoot:

$ mkdir redboot_ROMRAM
$ cd redboot_ROMRAM
$ ecosconfig new sama5d3xpld redboot
$ ecosconfig import $ECOS_REPOSITORY/packages/hal/arm/cortexa/sama5d3/sama5d3xpld/current/misc/redboot_ROMRAM.ecm
$ ecosconfig resolve
$ ecosconfig tree
$ make

The RedBoot Location section of the generic SAMA5D3 variant documentation provides a graphical representation of the ROMRAM model.

Building BootUp

Full details are provided in the BootUp Integration section.

Building AT91Bootstrap

As an alternative to the eCosPro BootUp second-level loader, the Atmel AT91Bootstrap second-level loader can be used to load a ROMRAM startup type application from the NVM boot memory into RAM for execution.

A version of the AT91Bootstrap source, modified by eCosCentric, is available in the directory $ECOS_REPOSITORY/packages/hal/arm/cortexa/sama5d3/var/current/misc/at91bootstrap. The original (as of writing) is v3.6.2 obtained by:

git clone https://github.com/linux4sam/at91bootstrap

The modifications provide example configurations to allow RedBoot to be loaded by the SAMA5D3X-EK and SAMA5D3 Xplained platforms, and to allow compilation using the eCosCentric cross-compilation tools (e.g. 4.7.3e release).

The AT91Bootstrap binary can be built from the provided source with the following steps:

cd at91bootstrap
make mrproper
make sama5d3_xplainednf_redboot_defconfig
export CROSS_COMPILE=arm-eabi-
make

The result of this process is a second-level boot loader binary binaries/sama5d3_xplained-nandflashboot-uboot-3.6.2.bin that can be installed into NAND using SAM-BA as described below.

Installing binaries with SAM-BA

A version of the Atmel SAM-BA tool which supports the at91sama5d3x-xplained target (e.g. v2-12 patch level 7) can be used to install your choice of BootUp, AT91Bootstrap, RedBoot or any other ROMRAM eCos application.