LiteX SoC build for MAX1000

[Antti Lukats]

Hi,

LiteX SoC with default VexRiscv RISC-C core is still much WiP but already booting LiteX BIOS and having SDRAM memtest OK on MAX1000

LiteX --->
https://github.com/enjoy-digital/litex

link to litex-boards fork with MAX1000 support
https://github.com/micro-FPGA/CRUVI/tree/master/tools/LiteX

Base SoC seems working, 8 LED's connected to GPIO, SPI Flash and user connectors, etc, not connected to anything.

Note 1: setting up LiteX may be a struggle, it is possible even on windows but the linux bootstrap is recommended way.

Note 2: LiteX has an open bug report - currently the generated ROM will be implemented as LUTROM on MAX10, so I had to manually patch the generated .v file, this will be fixed in LiteX, well hopefully



g
Antti

[BR]

Hi Antti,

A little late to reply on this, but i still find the MAX1000 board interesting.

I just tried and build the Litex SoC on the MAX1000 board and running into problems with the fitter (SRAM). I pulled the Litex from github source, trentz_max1000.py target. I see it was modified?? Is there a solution for it?

Is it possible to build a LiteX Linux image for the MAX1000 board on 8MB RAM? For example the ECP5 Colorlight i5 LFE5U-25F-6BG381C 24K LUT lattice SoC can run on 8MB Litex Linux. Perhaps the 16k MAX10 with 32MB RAM and 32MB FLASH board?

Thanks!

[Antti Lukats]

Hi,

we have not touched LiteX anymore for some time already so I can really not comment if/what problems may occur. If linux runs with 8MB RAM, it could maybe work on MAX1000 also, just my guess - but we have not tried it. LiteX itself should work but you need to make sure the RAM is inferred correctly if not it will give you error, I assume it should now work (there was a bug long time ago)

cheers
Antti

[BR]

Hi Antti,

I managed to get Litex SoC running on my MAX1000 8k 8MB RAM board, but only with the minimal RISCV cpu build.

It takes about 6k LUT space and almost all M9K memory. Building the normal RISCV cpu is >9k LUT don't know if the minimal RISCV cpu can run Linux.

Unfortunately I only own two MAX10 8k 8MB boards so maybe i need to get a 16k with 32MB RAM to get this running?

Thanks!

Regards,
BR

[BR]

Hi,

Linux Litex SoC build on the MAX1000 10M08SAU169C8G 8k board needs a vexriscv_smp cpu and yields > 8k LUTs. M9K memory is 97%, so it doesn't fit!

So Linux Litex SoC build on a 10M16SAU169C8G should work.
Total logic elements   8,616 / 15,840 ( 54 % )
Total memory bits   295,554 / 562,176 ( 53 % )

Regards,
BR

[Antti Lukats]

thanks for this feedback