Re: [Qemu-devel] [PATCH] SiFive RISC-V GPIO Device

[Alistair Francis]

On Wed, Feb 13, 2019 at 1:36 PM Peter Maydell <address@hidden> wrote:
>
> On Wed, 13 Feb 2019 at 18:54, Thomas Huth <address@hidden> wrote:
> >
> > On 2019-02-13 18:14, Peter Maydell wrote:
> > > On Wed, 13 Feb 2019 at 00:13, Alistair Francis <address@hidden> wrote:
> > >> I know the other RISC-V files don't do it, but this should go in the
> > >> hw/gpio directory instead of hw/riscv.
> > >
> > > It might be nice to move those existing riscv devices into
> > > their proper places at some point: should be a fairly easy
> > > cleanup patch if somebody wants to take it on. (Advice
> > > on what should live where available on request.)
> >
> > If devices only work on riscv, they should IMHO stay in hw/riscv/. I
> > think hw/gpio/ and friends should primarily be used if a device is
> > shared between architectures. If they stay in hw/riscv/ it is way easier
> > to match the devices with wildcards in the MAINTAINERS file. Just my
> > 0.02 € only, of course.
>
> This is not the way we generally arrange the source tree,
> at least not the parts I'm familiar with. The rule of
> thumb I use is that devices of type X go in hw/X, and
> hw/$ARCH is only for board models and SoC container objects.
> I think the model for this is the Linux kernel, which
> splits drivers for devices into directories by device
> family, rather than putting them all in arch/whatever.
> A split that puts all the architecture-specific device
> models in hw/$ARCH has the significant disadvantage that
> it would put a huge number of files in hw/arm ...

That is how I understood it as well.

I think some of the current files in hw/riscv/ could be moved, but
they are somewhat border line and we don't have many files yet so I
wasn't bothering yet.

This GPIO device doesn't have to be RISC-V specific so it makes sense
to put it under hw/gpio. The maintainers file will need to be updated
though.

Alistair

>
> (More generally, I don't think the exact way we split
> the source files between directories matters much, but
> I do think it helps if we try to be consistent about it.)
>
> thanks
> -- PMM