AM6548: Passing MAC ID from uboot

sarfaraz shaikh

Part Number: AM6548

Hi,

On our custom made board for AM6548 with silicon V2 we have 4 ICSSG Ethernet interfaces. As of now the ICSSG Interface generates random MAC addresses. We need to have fixed MAC ID to all 4 ethernets, where and what changes we need to make to make the MAC ID constant.

Thanks,

Sarfaraz

over 4 years ago

0 Vineet Roy over 4 years ago

TI__Mastermind 37435 points

Hi Sarfaraz,

Is this on Linux or RTOS ? The MAC for ICSSG is specified in a HW register but I will have to check how it's handled for Linux or RTOS.

Regards

Vineet

0 sarfaraz shaikh over 4 years ago in reply to Vineet Roy

Expert 1546 points

Hi Vineet, This is with Linux SDK 7.1.17 latest release.

TIA.

0 sarfaraz shaikh over 4 years ago in reply to sarfaraz shaikh

Expert 1546 points

Are there any steps to pass MAC ID to the Linux kernel during boot time ? I tried setting ICSSG MAC ID register from commandline devmem utility but this did not change the MAC for ethernet.

0 sarfaraz shaikh over 4 years ago in reply to sarfaraz shaikh

Expert 1546 points

Hi Vineet any update on this

0 Vineet Roy over 4 years ago in reply to sarfaraz shaikh

TI__Mastermind 37435 points

Hi Sarfaraz,

Sorry for the delay.

I digged a little bit and the MAC address is set in the file linux/drivers/net/ethernet/ti/icssg_prueth.c by this piece of code

mac_addr = of_get_mac_address(eth_node);

This in turn is populated from the DT which is populated by bootloader (Uboot)

If you see the uboot code, the MAC address is being set from the EEPROM by the function ks2_eth_read_rom_hwaddr() under uboot/drivers/net/ti/keystone_net.c. You can try editing this file and compiling U-boot for your board and give it a try.

Regards

Vineet

0 Vineet Roy over 4 years ago in reply to Vineet Roy

TI__Mastermind 37435 points

Hi Sarfaraz,

Correction to my post above.

On TI EVMs EEPROMs has MAC addresses and board_ti_am6_set_ethaddr() (board/ti/am65x) in U-Boot reads MAC addresses from EEPROM and sets ethXaddr env variables.

Eg.:

=> printenv
[...]
eth1addr=70:ff:76:1d:92:e4
eth2addr=70:ff:76:1d:92:e5
[...]

Generic U-Boot code then updates Linux ethernet port DT nodes'
'local-mac-address' or 'mac-address accordingly before jumping to kernel.

On custom boards its up to you to set ethXaddr env variables at U-Boot before starting kernel.

There is alternative - use DT 'local-mac-address' or 'mac-address' See this

Regards

Vineet

0 sarfaraz shaikh over 4 years ago in reply to Vineet Roy

Expert 1546 points

Hi Vineet,

by setting ethXaddr variable at the u-boot level we are able to se the MAC ID but the sequence to which MAC are set in PRU is getting distorted , like the PRU ethernet which comes up is taking the eth1addr address , ideally we want the eth1 should take the eth1addr and eth2 should take the eth2addr nut it is getting reversed. I have raised this issue on other forum ticket . attaching the link here.

https://e2e.ti.com/support/processors/f/processors-forum/987244/am6548-passing-pru-mac-id-from-uboot

+1 Vineet Roy over 4 years ago

TI__Mastermind 37435 points

Hi Sarfaraz,

Can I close this ticket since we are following it up here ?

Regards

Vineet

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AM6548: Passing MAC ID from uboot