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

[Fabien Chouteau]

On 15/01/2018 18:27, Jean-Christophe Dubois wrote:
> Le 2018-01-15 14:45, Jean-Christophe Dubois a écrit :
>>
>> Note: For now I am not so much interested in the AMBA discovery as the
>> type of software platform I am thinking about is embedded where the
>> hardware is well known ahead of time. This discovery capability would
>> make sense for more generic OS like linux or such. We cannot require
>> all embedded OS to implement the AMBA discovery process.
> 
> For the configurability of Qemu, I was thinking of using something similar to 
> the Qemu provided by Xilinx (http://www.wiki.xilinx.com/QEMU). Basically, you 
> provide a DTB file as a Qemu command line argument and Qemu will build the 
> various devices (including addresses and interrupts) based on the content of 
> this file. Then when running an OS, it can provide the DTB file (for example 
> to Linux) that match exactly the emulated platform.
> 
> This should allow to build "any" variation of the platform and to add devices 
> as you need them. This makes sense for Xilinx (their customer are building 
> custom platforms) and it would also make sense for LEON as the CPU core is 
> usually integrated inside a custom SOC/FPGA.
> 

Makes sense, another intermediate solution is to add an argument to the
function leon3_generic_hw_init(), A struct that specifies the address of
the peripherals. That way it will be easy to add more machine definition
without bringing more maintenance burden.