[LinuxBIOS] PhyWrite [SPI flash-chips] PCI ROM

Bari Ari bari at onelabs.com
Wed Mar 21 16:49:07 CET 2007

Stefan Reinauer wrote:

> I'd definitely give it a try if someone comes up with a HW solution.
> Does this require writing flash drivers in VHDL? 

I can get some boards and make some adapters.

They include a XC3S500E-4FG320C FPGA with 500K logic gates.

It seems like we can use the PicoBlaze cpu core:

The PicoBlaze instruction set can be found here:

There is a free C compiler found here:

A simulator and assembler for the picoblaze, with a graphical user 
interface, and an assembler for the picoblaze, with a command line 

KPicoSim is an IDE for the picoblaze microcontroller.KPicoSim is a 
development environment for the Xilinx PicoBlaze-3 soft-core processor 
for the KDE Desktop (Linux).The environment has an editor with syntax 
highlighting (based on the popular katepart), compiler, simulator and an 
export functions to VHDL, HEX and MEM files.

If it looks better to use a 32 bit cpu core and run uClinux we can use 
the MicroBlaze core. I'll have to see how well it fits into the 500K 
gates of the FPGA.

uClinux for the MicroBlaze

FLASH drivers aren't too complicated. Having the board emulate flash is 
mostly done in hardware. Ethernet would require a tcp\ip stack. We have 
a choice between doing everything in C on an 8-bit micro or uClinux on a 
32-bit cpu.

I have time do develop the hardware for this, but not much for software. 
I'll post all the schematics, regster info. and VHDL to the LinuxBIOS 
site. Let me know what everyone else thinks and prefers to use for the 
software end.


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