Re: [Qemu-devel] [PATCH RFC v1 00/29] ARC cores

[Michael Rolnik <mrolnik@gmail.com>]

H Alexey.

Thanks.

I need some help in getting a small code that exercises interrupts. For
several years I wrote FW for ARC based platforms (ARC4 & ARC6), but it
seems I forgot some of the things related to interrupts. I compiled
FreeRTOS demo from embARC, however I could not find interrupt vectors
there, I assume their board has ROM.
So, if you can help me with such a code, it would be great.

thanks,
Michael



On Fri, Sep 16, 2016 at 6:01 PM, Alexey Brodkin <Alexey.Brodkin@synopsys.com
> wrote:

> Hi Michael,
>
> On Fri, 2016-09-09 at 01:31 +0300, Michael Rolnik wrote:
> > This series of patches adds ARC target to QEMU. It indends to support
> >     - ARCtangent-A5 processor
> >     - ARC 600 processor
> >     - ARC 700 processor
> >
> > All instructions except ASLS are implemented. Not fully tested yet.
> > However I was able to execute correctly recursive fibonacci calculation.
> > Reset vector is assumed to be some hardcoded value which worked for my
> test.
> > I am planning to get FreeRTOS for ARC, once I get it, I will able to
> verify
> > and complete interrupt support.
>
> That's both very unexpected and cool!
>
> I tried your patches on top of current QEMU git master and it:
>  a) Builds for ARC
>  b) Very simple code really works!
>
> I was able to single-step with GDB through program as simple as:
> --------------------->8---------------------
> .global _start
> _start:
>         mov     r0, 1
>         mov     r1, 2
>         mov     r1, r0
> --------------------->8---------------------
>
> That's what I saw in GDB:
> --------------------->8---------------------
> (gdb) disassemble
> Dump of assembler code for function _start:
> => 0x00000100 <+0>:     mov     r0,0x1
>    0x00000104 <+4>:     mov     r1,0x2
>    0x00000108 <+8>:     mov     r1,r0
> End of assembler dump.
> (gdb) p $r0
> $1 = 0
> (gdb) stepi
> 0x00000104 in _start ()
> (gdb) p $r0
> $2 = 1
> (gdb) stepi
> 0x00000108 in _start ()
> (gdb) p $r1
> $3 = 2
> (gdb) stepi
> 0x0000010c in ?? ()
> (gdb) p $r1
> $4 = 1
> --------------------->8---------------------
>
> So again this is very promising even though a lot is essentially missing
> from
> this very first implementation.
>
> Anyways IMHO it would be good to have these patches accepted so people may
> start
> playing with that stuff adding missing things one by one.
>
> Let me know if you need any help from my side.
>
> Regards,
> Alexey




-- 
Best Regards,
Michael Rolnik