[coreboot] Questions about how to record hardware information on ARM

[Hamo]

> Are you thinking of extending the resource allocator? How does uboot
> do this? What would your device tree look like?
the resource allocator is based on PCI bus. We need a device's bus
number and device number to allocate resources to it. But on ARM, no
devices are connected to a PCI bus. So the device tree should not have
PCI-related fields.
U-boot uses a register r8 to store an address holding the device tree.
The tree records the information of the hardware on the board. After
U-boot finishes init one device, it writes the device's information to
the tree.