Re: Porting NetBSD to Eco32

[Jens Mehler <jens.mehler%mni.thm.de@localhost>]

Hello Yann,

Your problems with the locking sounds familiar.
Tripple check your spl.s - most locking and unlocking problems are
located there (I've been there - rewritten that stuff three times and
always forgot one silly thing) - additionally make sure that your
cpu_switchto is correct and that you have the atomic functions
implemented correctly. Find an architecture that is close to yours and
work your way from that up.

Ah you are using GDB - that's quite helpful. The Eco32 doesn't have a
GDB implementation ATM but maybe soon :)

I can't make my stuff public until next week I guess. It's my
masters-thesis and therefore I shall wait until it's all over (you know
that hassle). I will post the links here and share with everyone.

Ah yes those self-written userland-progs - I know them :)
We have 15 each of them tests another feature of the kernel - mostly
different syscalls and signals.
They are great for debugging and help you understand all those complex
subjects.

Porting libc is kinda crazy - took me a whole week ... that was month
ago... now I am still struggeling with 2°) Fix what breaks.

For some reason the libgcc isn't build - which is needed for almost any
program because of floating_point arithmetic. The next thing is that I
can't build shared libs - never bothered with that idea since I wanted
to keep it simple. I guess it could work but never actually tried it out
because without an OS we can only load statically linked executables
from the disc. (We have written our own elf loader).
Therefore we are stuck with mknative for GCC XD - it fails on several
occasions - a file missing here an there.

If you get around to a userland port of your machine it would be great
if you could post an update on that.
I will do the same as soon as I see progress (which is actually progress
and not another red herring :P ).

With best regards and happy hacking,
Jens



On 22.09.2014 21:45, Yann Sionneau wrote:
> Hello Jens,
>
> Good to hear you are making progress and the kernel is finally stable :)
>
> I also made some progress, (TLDR here is my progress :
> https://www.edgebsd.org/edgebsd/wiki/14/port-lm32 ) I can now execute
> some user space instructions.
> I can actually execute a small statically linked /sbin/init program
> which just opens /dev/console 3 times and write "hello, world!" to it,
> which is displayed on UART console.
>
> I'm pretty happy about that :)
>
> But I would also like to start having more user space than just my
> small /sbin/init ;)
>
> I think the next step for me is porting some libc and then iterating
> on the following items :
>
> 1°) ./build.sh -m milkymist -U -u release
> 2°) Fix what breaks
> 3°) goto 1°)
>
> Until everything compiles
>
> But I think it's quite a lot of work!
>
> Also, I still have a bit of work in the kernel, I just fixed my
> spl**() functions but I still have issues with locking. Sometimes it
> would not boot very far, sometimes it would boot up to printing the
> hello world and letting me type (sys_read()) to the init stdin.
>
> Cheers!
>
> Yann
>
> 2014-09-20 9:35 GMT+02:00 Jens Mehler <jens.mehler%mni.thm.de@localhost
> <mailto:jens.mehler%mni.thm.de@localhost>>:
>
>     Hi Yann,
>
>     I am still trying to port the NetBSD Userland after the Kernel finally
>     got into a stable state :) (A lot of troubles with GCC has been
>     resolved) O2 kernel is now possible.
>
>     Did you get a hang on the Userland-port?
>     We are still struggling with that one :)
>
>     With best regards,
>     Jens
>
>     On 24.06.2014 19:04, Yann Sionneau wrote:
>     > Le 24/06/14 16:33, Jens Mehler a écrit :
>     >> Hi everyone !
>     >>
>     >> Currently a small team is porting NetBSD to a new processor called
>     >> eco32. It's an educational 32bit RISC processor for which I had
>     already
>     >> ported GCC and Binutils.
>     >>
>     > Hi Jens,
>     >
>     > Pretty cool project :)
>     >
>     > Which implementation of Eco32 are you running your NetBSD kernel on?
>     > This one: https://github.com/skristiansson/eco32f ? On which
>     FPGA board?
>     > Is it supported in Qemu ?
>     > Can you post a link to your NetBSD tree?
>     >
>     > Looking forward to hear more about it :)
>     >
>     > FYI I am porting on LatticeMico32 which is also a 32 bit RISC
>     >
>     > Cheers!
>     >
>
>
>
>
> -- 
> Yann Sionneau