Recovery U-Boot Image (Naon)

Info Box Applies to Naon

Introduction

For different reason, starting from image corruption due power loss during upgrade or unrecoverable bug while developing a new U-Boot feature, the user will need, sooner or later, to recover his/her Naon SOM without using U-Boot itself.

In this article we'll see a few useful option for w:Bare-metal restore of a Naon module.

As prerequisite, we suggest an in-depth read of Naon boot sequence and options, Naon memory organization and Naon Flashing images because all this topic are required to understand the followings.

JTAG Recovery

JTAG recovery is very useful, especially in development or production environment. However it requires a dedicated hardware (which most of the time, is very expensive).

Due hardware dependency we can't cover all JTAG tool example, but we'll see two of them to give the user a brief introduction on the argument. If you need more support you can alway contact our Techinical Support Team

Lauterbach ICD Naon booting

This script for Lauterbach ICD for ARM Cortex-A8 allow the user to:

• configure T32 correctly
• establish a connection with the target (which should already be powered on)
• load u-boot.bin into internal SRAM
• run it

At this point the user should be able to run commands from U-Boot serial console.

As a more advance example, This script, after loading the 1st stage and have it run until RAM initialization, also load 2nd stage (at 0x81000000). This is faster that loading the 2nd stage via serial protocol. After executing the script, the user should just type go 81000000 from U-Boot 1st stage prompt, to run the 2nd stage:

U-Boot 2010.06-dirty (Apr 20 2012 - 17:15:51) [nelk-0.0.3]

U-Boot code: 40300000 -> 4030D0E4  BSS: -> 4030E2EC
TI8148-GP rev 2.1

ARM clk: 600MHz
DDR clk: 400MHz

RAM Configuration:
Bank #0: 80000000 512 MiB
Using default environment

### main_loop entered: bootdelay=0

### main_loop: bootcmd=""
Hit any key to stop autoboot:  0
NAON-MIN#go 81000000
## Starting application at 0x81000000 ...


U-Boot 2010.06-dirty (Apr 30 2012 - 19:23:20) [nelk-0.9.0]

TI8148-GP rev 2.1

ARM clk: 600MHz
DDR clk: 333MHz

I2C:   ready
DRAM:  512 MiB
NAND:  HW ECC Hamming Code selected
1024 MiB
MMC:   OMAP SD/MMC: 0
Net:   Detected MACID:d4:94:a1:8e:46:a4
cpsw
Hit any key to stop autoboot:  0
NAON#

If needed, the customer can contact us for more scripts or suggestion, for example to debug U-Boot or Linux kernel.

Code Composer Studio (CCS) and Spectrum Digital XDS560V2 STM USB

This combination of tool is described into this article of Texas Instruments Wiki.

More article on CCS are available into its dedicated section of TI Wiki.

UART Recovery

UART recovery does not requires any specialized hardware, apart a PC (Windows or Linux based) and a DB9 serial cross cable.

If not already available, configure Naon boot sequence to include UART boot.

To verify this, is enough to open a serial terminal (115200 8N1) and power on the board. If everything is correctly configured you should see a sequence of CCC on your screen.

Please follow this instructions on TI Wiki to load both 1st and 2nd stages of U-Boot.

When the 2nd stage is running follow this article for instructions on how to update U-Boot in flash