Dynamic MAC address setting in DM8168

Salih,

Muhammad Salih said:

But while launching the Linux, the MAC address is reading from e-fuse registers and I am not getting the MAC address which I set in the U-boot.

Where do you see/check that MAC address is changed in the linux kernel? Is it from the linux kernel boot up console output or with some user space command?

Regards,
Pavel

I trace the linux kernel code and found this:

ti-ezsdk_dm816x-evm_5_05_02_00/board-support/linux-2.6.37-psp04.04.00.01/arch/arm/mach-omap2/devices.c

void ti816x_ethernet_init(void)
{
u32 mac_lo, mac_hi;

mac_lo = omap_ctrl_readl(TI81XX_CONTROL_MAC_ID0_LO);
mac_hi = omap_ctrl_readl(TI81XX_CONTROL_MAC_ID0_HI);
ti816x_emac1_pdata.mac_addr[0] = mac_hi & 0xFF;
ti816x_emac1_pdata.mac_addr[1] = (mac_hi & 0xFF00) >> 8;
ti816x_emac1_pdata.mac_addr[2] = (mac_hi & 0xFF0000) >> 16;
ti816x_emac1_pdata.mac_addr[3] = (mac_hi & 0xFF000000) >> 24;
ti816x_emac1_pdata.mac_addr[4] = mac_lo & 0xFF;
ti816x_emac1_pdata.mac_addr[5] = (mac_lo & 0xFF00) >> 8;
........
}

Can you try comment this two lines:

//mac_lo = omap_ctrl_readl(TI81XX_CONTROL_MAC_ID0_LO);
//mac_hi = omap_ctrl_readl(TI81XX_CONTROL_MAC_ID0_HI);
Then set the MAC ID manually:
mac_lo = <your value>
mac_hi =<your value>

When setting a MAC address please ensure that the LS-bit of the 1st byte is not 1 i.e. when setting the MAC address: y in xy:ab:cd:ef:gh:jk has to be an even number.

See also the below e2e thread:
e2e.ti.com/.../82859

BR
Pavel

Hi,

I am using the command "ifconfig" in the Linux Kernel console. I want to fetch the MAC address from U-boot which I am manually setting in it. Below is the command which I am using to set the MAC:

iW-G12M-U-Boot > setenv ethaddr '02:03:04:05:06:08'

How can I fetch this value in my Linux kernel without modifying the Linux source code.

Thanks in advance.

Regards,
Salih

Hi,

And also, is it possible to re-program the e-fuse registers once it is already programmed?. If so, how can I do the same in my source code.

Thanks in advance.

Regards,
Salih

Salih,

Muhammad Salih said:

And also, is it possible to re-program the e-fuse registers once it is already programmed?

No, you can not. The e-fuse registers (MAC_ID0_LO, MAC_ID0_HI, MAC_ID1_LO, MAC_ID1_HI) are read only.

You can try with the EMAC MACADDRLO and MACADDRHI registers, which are read/write.


BR
Pavel

Hi Pavel,

Thanks for your reply. I want to know, whether all the DM8168 Processor having the valid MAC ID which purchased by IEEE. If so, is it possible to use the same MAC ID for our product?.

Thanks in advance.

Regards,
Salih

Muhammad Salih said:

I want to know, whether all the DM8168 Processor having the valid MAC ID which purchased by IEEE. If so, is it possible to use the same MAC ID for our product?

Yes you can. See below e2e threads for more info:

Regards,
Pavel