On 13.02.19 02:31, Bin Meng wrote:
On Tue, Feb 12, 2019 at 6:23 PM Andreas Schwab schwab@suse.de wrote:
On Feb 12 2019, Bin Meng bmeng.cn@gmail.com wrote:
The env var is stored in whatever supported media in U-Boot. Not like PCI NICs which normally have EEPROM to store pre-flashed MAC address by their vendors, for most embedded network controllers in the SoC, normally there is no hardware provided mechanism to ensure a unique MAC address, instead it relies on software to program one to the hardware before bringing it up.
On the Hifive the MAC is part of the initial DT, so there is no need to use a secondary store.
So for the HiFive board, who is supposed to guarantee the uniqueness of the MAC address? Does SiFive program DT with different MAC to every board they shipped? If so, we can just read "local-mac-address" from DT in U-Boot.
The DT is supplied via SD card, just like U-Boot is. So it's up to the user to modify the DT and ensure that it contains a unique MAC address.
Alex