[J-core] Port Idea: Little Kernel

[Rob Landley]

On 11/11/2017 02:42 PM, Cedric BAIL wrote:
>> I looked at that commit and it sounds quite simple to add the same
>> tests for all the other instructions. I was planning to use my JSON
>> file for this kind of purpose and generate most of it automatically. I
>> will try to look at it this weekend or during next week. Would you
>> mind sharing the binary you are using to do your current tests with
>> sh2 ? I am guessing I can use a sh4 debian to test if the features
>> tests are enable and result in an illegal instruction.
> 
> It was indeed pretty easy to write the code. I have made necessary
> change to qemu to handle the entire SuperH family over night. I don't

Ooh, very nice. Do you have a patch I can look at?

> really know where to go for a few bits, especially regarding the board
> definition. This means it is not tested (Just previous SH4A code now
> work with the new logic generated from my JSON file and I can still
> start debian on my modified version). You can have a look at it here :
> https://github.com/Bluebugs/qemu . If anyone has a clue on a proper
> direction for the board definition, would be neat.

What I was hoping to do was get qemu to run the existing numato/turtle
vmlinux binaries and cpio root filesystems. (Numato and turtle run the
same kernel config on vanilla at the moment. The turtle-only hardware,
like ethernet, hasn't got drivers in vanilla yet. I'm hoping we can fix
some of that in the 4.15 dev cycle.)

Lemme try to get you some reference binaries I've built with mkroot and
tested on the hardware...

> Also I discovered a few bugs in the JSON file I had that cover SuperH
> instruction set. I have updated my git repo
> (https://github.com/Bluebugs/sh-insns) with the assumed correct
> version from qemu. Maybe someone here has an idea if this is actually
> correct :
>    sets: "0000000001011000"
>    ldc Rm,DBR: "0100mmmm11111010"

That's a question for Jeff or Rich.

Rob