Dump memory to file from U-Boot console using Memory Display (md) log

 Introduction

Dump firmware or other contents from memory of a device with U-Boot bootloader to a file by converting output of memory display (md) command to binary image.

 Steps

1. Connect to U-Boot console using picocom and save all outputs in a log file using commad given below. Here the output is saved to log file named 'mdb.log'.

sudo picocom /dev/ttyUSB0 --baud 115200 --logfile mdb.log


2. Display the contents of the memory using command:

md.b <address> <length>

Figure below shows the command to display memory contents from address 0x400000000 and of length 0x20000 (128KB) . The data in this example corresponds to a jffs2 file system.


3. Once the execution completes, edit the log file and remove everything other than md.b output.

4. Clone the github project uboot-mdb-dump.git

git clone https://github.com/gmbnomis/uboot-mdb-dump.git


5. Generate the binary image file 'output.bin' from log file 'mdb.log'.

python3 uboot-mdb-dump/uboot_mdb_to_image.py < mdb.log > output.bin


Video



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