Kontron NetBootLoader - Manual (Page 24)

ID 1022-8317, Rev. 2.0
NBL Operation NetBootLoader
Page 16
2.8.6 Uploading an NBL Flash Memory Area
The NetBootLoader also has the possibility to upload certain areas of the NBL Flash memory
to a host using an Ethernet port. To use this interface, the Ethernet port parameters must first
be set and then the operator must gain control of the NetBootLoader and perform an FTP serv-
er login. After a successful login, the operator then stores the NBL Flash memory area to be
uploaded to the local data buffer using the SF command. Using the PUT command transfers
the contents of the data buffer to the FTP server. As with any type of server session, the oper-
ator should logout when the session is finished.
2.9 Plug and Play
The NetBootLoader includes “Plug and Play” functionality. This ensures that the CPU module
is completely initialized and that all resources necessary for PCI devices (addresses, interrupts
etc.) are assigned automatically. This important feature has the advantage that conflicts do not
arise when PCI devices are added or removed as the operating system itself does not include
the board initialization code.
2.10 Porting an Operating System to the CPU Board
The image for the absolute address 0x0 should be linked with an entry point at the absolute
address 0x0 (FDT enabled) or 0x100 (FDT disabled).
One should not attempt to reassign the PCI BAR registers. The assigned values should be read
back and these should always be used in the drivers.
Downloaded images are never executed from the NBL Flash memory. The programmed image
is always downloaded to DDR2-SDRAM, the absolute address 0x0 being downloaded first.
There is no configuration option available to amend this process. If it is necessary to relocate
the image to another address after download, simply add a small assembly routine at the be-
ginning of the code which will move the image to the correct address.
2.11 NBL Flash and NAND Flash Usage
The NetBootLoader was originally designed for CPU modules that only had a single NBL Flash
memory device. The introduction of CPU modules with two NBL Flashes and NAND Flash has
significantly increased the flexibility of systems not only with regards to the NetBootLoader it-
self, but also with regards to operating systems and ultimately applications as a whole.
The first Kontron product with these features, the AM4100 AMC CPU module, was provided
with both redundant NBL Flash as well as NAND Flash. These features have contributed to in-
creased system availability (NetBootLoader backup controlled by IPMI system management)
and a very high degree of system autonomy and ruggedness (high capacity of onboard solid
state memory for operating systems and applications).
To support these enhancement features, various existing commands were modified and new
commands were added.