Re: [PATCH 08/15] riscv: provide native clint access for M-mode

Christoph Hellwig
2019-08-19T10:16:53Z

On Tue, Aug 13, 2019 at 05:29:58PM +0100, Mark Rutland wrote:
> > + np = of_find_compatible_node(NULL, NULL, "riscv,clint0");
>
> Since the MMIO layout is that of the SiFive clint, the compatible string
> should be specific to that. e.g. "sifive,clint". That way it will be
> possible to distinguish it from other implementations.
>
> What exactly is the "0" suffix for? Is that a version number?
>
> If that's a CPU index, then I don't think that's the right way to encode
> this unless the programming interface actually differs across CPUs. It
> would be better to use an explicit phandle to express the affinity.

It isn't a cpu index, I suspect a version number. These show up
in a lot of the early RISC-V DTs coming from the UCB/SiFive sphere.
They've now spread everywhere unfortunately.