of_get_mac_address — Get best MAC address
const void * of_get_mac_address ( | struct device_node * np) ; |
Search the device tree for the best MAC address to use. The value of property “mac-address” is checked first, because that is supposed to contain to “most recent” MAC address. If that isn't set, then the value of property “local-mac-address” is checked next, because that is the default address. If that isn't set, then the value of the obsolete property “address” is checked, just in case we're using an old device tree.
Note that the “address” property is supposed to contain a virtual address of the register set, but some DTS files have redefined that property to be the MAC address.
All-zero MAC addresses are rejected, because those could be properties that exist in the device tree, but were not set by U-Boot. For example, the DTS could define “mac-address” and “local-mac-address”, with zero MAC addresses. Some older U-Boots only initialized “local-mac-address”. In this case, the real MAC is in “local-mac-address”, and “mac-address” exists but is all zeros.