Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Unique MAC address without using a flash memory and without prompting the user?

Dear Sirs, I am facing a little challenge with MAC addresses here. The default way of assigning a MAC address is by reading it from flash memory. Below is an example (from nios2eds/examples/s...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

--- Quote Start ---

Where is the board serial number coming from? You'll have the same issue with that as a MAC, i.e., either can get erased.

--- Quote End ---

The serial is coming from the motherboard of the host PC. You can get one through the DMI sub-system of the Linux kernel, for example: 

# include <linux/dmi.h>
static int get_board_serial(u64 *dst)
{
    const char *s;
    s = dmi_get_system_info(DMI_BOARD_SERIAL);
    if (!s)
        return -1;
    if (kstrtou64(s, 10, dst))
        return -1;
    return 0;
}

This should make the unique, consistent MAC address (I don't like the idea of a random one!). I am also planning to provide a way to change it through ethtool.