On Wed, Jul 20, 2016 at 04:58:08AM +0200, Marek Vasut wrote: > On 07/20/2016 04:50 AM, Brian Norris wrote: > > On Wed, Jul 20, 2016 at 03:50:27AM +0200, Marek Vasut wrote: > >> On 07/19/2016 10:05 PM, Brian Norris wrote: > >>> On Tue, Jul 19, 2016 at 08:03:00AM +0200, Stefan Roese wrote: > >>>> On 18.07.2016 22:20, Brian Norris wrote: > >>>>> Hmm, does x86 not define readsl()/writesl()? I can never tell what > >>>>> accessors are supposed to be "standard" across architectures. > >>>>> > >>>>> Either we need to drop the COMPILE_TEST or maybe make it (!X86 && > >>>>> COMPILE_TEST). > >>>> > >>>> iowrite32_rep() etc should work for x86 as well. > >>> > >>> Looks like it might. I'm not sure the original submitter can retest > >>> right now (travel), so I'd probably rather just take the easy fix for > >>> now, and we can widen to COMPILE_TEST later if desired. > >> > >> Isn't there a generic readsl() and writesl() implementation in > >> include/asm-generic/io.h ? > > > > Yes, but somehow x86 has managed to avoid that. I guess it's optional > > for arch/<foo>/include/asm/io.h to include <asm-generic/io.h>? At any > > rate, I double-checked myself by adding '#error "blah"' to > > include/asm-generic/io.h, and x86 still seemed to build fine (at least > > for the modules I was checking, like cadence-quadspi.o). > > Yep, I just checked the same and it's not included from > arch/x86/include/asm/io.h for whatever reason. Maybe this needs to be > fixed on x86 level?
Maybe. That's why I added the x86 maintainers. Maybe they'd respond better^Wmore loudly if I just sent a patch to do that :) But seriously, doing the above really breaks things, even if I stick the include at the end of asm/io.h. There's plenty of stuff that the asm-generic version includes based on #ifndef some_accessor, except x86 uses a static inline for their definition. So it seems it's not trivial to get an architecture to fall back gracefully to asm-generic; you have to put in some work. It also may not be all that desirable to have some allegedly generic version generate something that may not be safe on a given architecture (and I don't purport to understand the x86 memory model). Additionally, it looks like asm-generic/io.h is actually only included in 14 of 33 arch'es, so it seems like that's really not a designated goal. It does make it awfully difficult to figure out what I/O accessors are *actually* portable though... Brian
