NVRAM usage in Emebedded System

Refer to: Non-volatile random-access memory

NVRAM can be replaced by SRAM with battery . 

In Linux, mostly NVRAM is statically mapped to memory space.

MTD partition is built on top of it, which can be used for sequential

reading/writing or block device simulation  for filesystem. 

To verify data integrity on NVRAM:

bash-3.2# flash_eraseall -j /dev/mtd3

Erasing 16 Kibyte @ 1fc000 -- 99 % complete. Cleanmarker written at 1fc000.

bash-3.2# mkdir /mnt/flash

bash-3.2# mount -t jffs2 /dev/mtdblock3 /mnt/flash

bash-3.2# ls -al test.img

-rw-rw-rw- 1 root root 262144 Jan  9 00:34 test.img

bash-3.2# cp test.img /mnt/flash/

bash-3.2# md5sum /mnt/flash/test.img

ec87a838931d4d5d2e94a04644788a55  /mnt/flash/test.img

 

short notes using KGDB on X86

Using kgdb, kdb and the kernel debugger internals
Using kgdb and the kgdb Internals

1.) Configure, Compile and Load the kernel
CONFIG_KGDB=y
CONFIG_KGDB_SERIAL_CONSOLE=y
2.) Check the /pro/cmdline
bash-3.2# cat /proc/cmdline
rw root=/dev/ram0 ide_generic.probe_mask=0x0 kgdboc=ttyS0,9600,B
3.) Check sysfs
bash-3.2# cat /sys/module/kgdboc/parameters/kgdboc
ttyS0,9600,B
4.) Trigger the kernel to kgdb
bash-3.2# echo g > /proc/sysrq-trigger
[  489.043906] SysRq : GDB
5.) gdb vmlinux
(gdb) target remote 10.193.65.8:2051

Remote debugging using 10.193.65.8:2051




Do what you want from here.
Enjoy debugging.......