[U-Boot-Users] FPGA loading question

[Matthias Fuchs <matthias.fuchs@esd-electronics.com>]

Hi <no forename>,

On Wednesday 26 September 2007 22:48, E Robertson wrote:
> Hi All,
> I've got a Spartan3E fpga I'm trying to program serially with a bin file.
fine.

> Is there any similar driver available to so this?
You can use the U-Boot fpga subsystem. See common/cmd_fpga.c
You have to write same board specific code to access the FPGA's
serial interface.

> I'm not sure if this is better done as a driver with embedded binary
> or as part of a hust script but the bin file embedded in the u-boot
> source. (I'm not sure if the latter is possible).
Nearly everything is possible:-) Even embedded FPGA binaries are
used with some U-Boot'supported boards (we have some of these), I must
say that's not best practice - and we will stop doing this:-).
Since FPGA's are getting bigger and bigger you end up with large 
binary images in the U-Boot sourcetree. 

I suggest to write the binary FPGA images in a separate flash
section. You can make the FPGA subsystem to automatically boot the
FPGA by setting an environment variable to the image's baseaddress
or you can start the boot process from the command line ...

What kind of CPU are you using? Please note that 4xx U-Boot ports have
the cache disabled. Without cache booting a Spartan 3E in SS-mode
may take very very :-(

Matthias