Re: [Qemu-devel] [PATCH] LEON3 IRQMP: Fix IRQ software ack

[Fabien Chouteau]

On 12/01/2018 15:10, Jean-Christophe Dubois wrote:
> Le 2018-01-12 11:55, Fabien Chouteau a écrit :
>> On 11/01/2018 13:35, Jean-Christophe Dubois wrote:
>>> Thanks Fabien,
>>>
>>> Now, as a side question, could you tell me which reference LEON3 platform 
>>> is implemented by Qemu in leon3_generic?
>>>
>>
>> I think it was the based on the FPGA version of Leon3 I was using at the
>> time. The name leon3_generic comes from my will to make it a
>> configurable board where users could define the number and the location
>> of the different peripherals, I never had time to work on this.
> 
> I see. I am not sure how to bring configurability to Qemu. There is the 
> possibility to describe the hw PTF with DTC/DTB or something similar. I think 
> some people were working on it for the ARM Qemu platform (but I am not sure 
> what happened to this initiative).
> 
> Now in the meantime, would it make sense to move leon3_generic to a tsim 
> compatible platform?
> 

I don't think so, leon3_generic is compatible with a real hardware which
is also interesting for comparison.

> This would allow to validate the same software on the 2 simulators (obviously 
> it would not be compatible with your specific FPGA version for now).
>

The Leon3 AMBA bus provides a way to discover the peripherals and their
address, so any system should be capable of supporting different
peripheral layouts.

Here's an example of AMBA discovery code from a very old project of mine
(don't judge me on this :) :
https://github.com/Fabien-Chouteau/kabitbol/blob/master/src/amba.c

There was a couple of patches submitted some times ago to add Leon3 AMBA
support in QEMU, I think it's time to bring them back...