[J-core] qemu updates / roadmap

[D. Jeff Dionne]

On May 15, 2016, at 9:10, Christopher Friedt <chrisfriedt at gmail.com> wrote:
> 
> I actually had to disable CONFIG_CPU_TESTS because otherwise I was getting stuck in _fail.

That is not necessarily ok to do.  While there are a few instructions that will not be available unless you've coded support for them, tests for those (and maybe it's only CAS.L actually) should be #ifdef out and the rest shown to pass.  The easiest way to do that is to bring the LED port out to a console print (in qemu) and see where it stops.  The tests count in BCD, the top 4 bits are the instruction 'group' and the lower 4 the test number in the group.  I would want to know at least which instruction is failing, (other than CAS.L).

During the debug of the CPU, this is/was fundamental to being able to tell exactly -what- wasn't/isn't working quite right.  It tries to check for corner cases, etc.  There is a pretty good chance if you can get to 0110 0010 test passing, you can call the CPU emulation 'good' and assume any problems are likely elsewhere.

J.