Re: Gpio in vexpress

[Peter Maydell]

On Thu, 18 May 2023 at 15:36, ido berenbaum <ido.ber3@gmail.com> wrote:
>
> Oh, I was under the impression the vexpress board is not based on a real 
> physical hardware like virt.

Yep; the motherboard part is documented here:
https://developer.arm.com/documentation/dui0447/latest/
and the daughterboards are:
https://developer.arm.com/documentation/dui0448/latest/ (A9)
https://developer.arm.com/documentation/dui0604/latest/ (A15)

> In any case, In my workplace we use the qemu for our CI testing, to prevent 
> the need to use our hardware for logical tests.
> The thing is our SoC is not implemented in qemu, and so we are using the 
> vexpress as it is similar enough when considering the core structure.
> But, as it is not identical we need to make changes to make it fit our use 
> cases. For example, add a gpio.
>
> Do you think we should use a different SoC as a base for our development?

If you're just doing local hacks you can do whatever
you like. Upstream we won't take changes which don't
match the real vexpress hardware, and that didn't include
any GPIO controllers.

If the guest code you're running is expecting to run on
your actual SoC you might consider modelling it, but
this is a fair amount of work.

thanks
-- PMM