Re: [PATCH -next] net: hisilicon: Never build on SPARC

[Arnd Bergmann <arnd@arndb.de>]

On Wednesday 21 October 2015 10:03:05 Guenter Roeck wrote:
> >
> > Something like this?
> >
> > static inline u64 of_translate_address(struct device_node *np, const __be32 *addr)
> > {
> > #if defined(CONFIG_SPARC) || defined(CONFIG_M68K)
> >       int pna = of_n_addr_cells(np);
> >       u64 ret = be32_to_cpu(addr[pna - 1]);
> >
> >       if (pna > 1)
> >               ret += (u64)be32_to_cpu(addr[pna - 2]) << 32;
> >
> >       return ret;
> 
> That suggests that sparc would need a translation after all, which
> seems to contradict what David said earlier.

No, not a translation: the value is used without any offset that
factors in the location of the bus, the above is just the shortest
possible way to read the 64-bit number from a big-endian property
of variable length.

> Anyway, if it gets that complicated, I think we should stick with
> just returning OF_BAD_ADDR. The above really suggests the need for
> an architecture specific solution.

Probably no harm in this really: the far more common
of_address_to_resource() and of_iomap() helpers are equally
broken on SPARC and we just return a runtime error for those
as well without CONFIG_OF_ADDRESS rather than breaking the build.

	Arnd