RM0082
BootROM
Doc ID 018672 Rev 1
841/844
38.5.5 Ethernet
boot
The Ethernet boot is specifically used to boot the devices which do not have a storage
capacity. There are two phases in this kind of booting. For any device to communicate in an
IP network, it needs to have an IP of its own. This can be a fixed IP which is stored in a non-
volatile memory within the device or a new IP can be obtained through BOOTP server.
BOOTP is a protocol which facilitates obtaining the IP from a server. This is essentially the
first phase of booting in the case of Ethernet boot.
The second stage of booting starts after the device has its own IP and the device can
communicate with the TFTP server to download images. This stage consists of downloading
an executable image from the TFTP server via the TFTP protocol and executing that image.
The first image which is downloaded is X-Loader and it is responsible for initializing the
PLLs and DDR memory. The U-boot image is downloaded and run after X-Loader has
completely run.
Please note that this booting also does not require any non-volatile memory to be present
on the board.