Linux capable free/GPL SOFT CPU for XC3S500E?

On Wed, 7 Nov 2007, ghelbig@lycos.com wrote:

> Linux will run on a soft CPU, including ones that fit into the
> XC3S500.  There are uClinux ports for both the MicroBlaze and NIOS.
>

Yes, I know, however I'm looking for an open solution, which I could both 
give away to students, and to use in some research applications.
So the problem is that the cores should be open source and with 
permissive (preferrably free or even GPL) license.

> A point to mention is that uClinux runs without a memory manager.
> There just aren't enough gates to fit one in an FPGA.
>
> If you can't find an open-source port to MicroBlaze or NIOS, look for
> an ARM7 port.  An ARM7 is an ARM9 with the memory manager removed.
>

Well, however the only freely available synthesizable ARM7 implementation 
is the nnARM, which after its disappearance from OpenCores in 2001 is 
still available in many mirrors (just google for sARM_tb.zip ;-) ), but 
AFAIK it is not safe to use due to legal issues (and is not complete as well).
-- 
Thanks and regards,
Wojtek

On Nov 5, 2:11 pm, Wojciech Zabolotny <w...@ipebio15.ise.pw.edu.pl>
wrote:
> Hi All,
>
> I'm looking for a possibility to run Linux (may be a ucLinux) on a
> XC3S500E containing CPU and some custom peripherials.
> The hardware platform should be a Spartan3E Starter Kit (rev. D),
> or something like this.
>
> I have found the almost ready to use solution here:http://muranaka.info/pukiwiki/index.php?MicroBlaze%20uClinux%20and%20...
> but it is MicroBlaze based, which is not acceptable for me due to
> licensing terms (which are even worse for the Ethernet MAC controller).
> Has anybody tried to use the aeMB clone with the free OpenCores Ethernet
> MAC controller with the MicroBlaze ucLinux?
>
> The OpenRisc and LEON3 seem to be too big for XC3S500E (or at least I
> was not able to trim them sufficiently for this FPGA).
>
> The most preferable solution seem to be a CPU which has a standard
> instruction set (e.g. Plasma, which is MIPS I compatible), because in
> this case the toolchain is well supported.
>
> However I could not find any information if it is possible to run Linux
> on the Plasma (or mips789) SOFT CPU.
> Has anybody any experience in that subject?
>
> There is an ideal solution announced on the OpenCores:http://www.opencores.org/projects.cgi/web/m1_core/overview
> But it is only an idea (Development status :: alpha)
> --
> TIA & Regards,
> Wojtek Zabolotny

Linux will run on a soft CPU, including ones that fit into the
XC3S500.  There are uClinux ports for both the MicroBlaze and NIOS.

A point to mention is that uClinux runs without a memory manager.
There just aren't enough gates to fit one in an FPGA.

If you can't find an open-source port to MicroBlaze or NIOS, look for
an ARM7 port.  An ARM7 is an ARM9 with the memory manager removed.

Hope that helps,
G.