On 07/20/2014 04:38 PM, Chen Gang wrote: > On 07/19/2014 02:02 AM, Chen Gang wrote: >>> 2014-07-18 18:51 GMT+08:00 Richard Weinberger <richard@xxxxxx>: >>>> Am 18.07.2014 12:44, schrieb Chen Gang: >>>>> On 07/18/2014 03:35 PM, Richard Weinberger wrote: >>>>>> Am 18.07.2014 02:36, schrieb Chen Gang: >>>>>>> >>>>>>> On 07/18/2014 02:09 AM, Richard Weinberger wrote: >>>>>>>> Am 17.07.2014 12:48, schrieb Arnd Bergmann: >>>>>>>>> AFAICT, NO_IOMEM only has a real purpose on UML these days. Could we take >>>>>>>>> a shortcut here and make COMPILE_TEST depend on !UML? Getting random stuff >>>>>>>>> to build on UML seems pointless to me and we special-case it in a number of >>>>>>>>> places already. >>>>>>>> >>>>>>>> If UML is the only arch without io memory the dependency on !UML seems >>>>>>>> reasonable to me. :-) >>>>>>>> >>>>>>> >>>>>>> For me, if only uml left, I suggest to implement dummy functions within >>>>>>> uml instead of let CONFIG_UML appear in generic include directory. And >>>>>>> then remove all HAS_IOMEM and NO_IOMEM from kernel. >>>>>> >>>>>> Erm, this is something completely different. >>>>>> I thought we're focusing on COMPILE_TEST? >>>>>> >>>>> >>>>> COMPILE_TEST is none-architecture specific, but UML is. So in generic >>>>> include folder, if we're focusing on choosing whether COMPILE_TEST or >>>>> UML, for me, I will choose COMPILE_TEST. >>>>> >>>>> If we're not only focusing on COMPILE_TEST, for me, if something only >>>>> depend on one architecture, I'd like to put them under "arch/*/" folder. >>>>> >>>>> Especially, after that, we can remove all HAS_IOMEM and NO_IOMEM, nobody >>>>> has to think of them again. :-) >>>> >>>> And then we end up with a solution that on UML a lot of completely useless >>>> drivers are build which fail in various interesting manners because you'll >>>> add stubs for all kinds of io memory related functions to arch/um/? >>>> We had this kind of discussion already. You'll need more than ioremap... >>>> >>>> I like Arnd's idea *much* more to make COMPILE_TEST depend on !UML. >>>> >> >> That will let UML itself against COMPILE_TEST (but all the other >> architectures not). >> >> And if let COMPILE_TEST depend on !UML, can we still remove all >> HAS_IOMEM and NO_IOMEM from kernel? (I guess so). >> >> If we can remove them, we can send related patch firstly -- that will >> let current discussion be in UML architecture wide instead of kernel >> wide. >> > > Next, I shall: > > - Remove HAS_IOMEM and NO_IOMEM from kernel, firstly. > > - Try to make dummy IOMEM functions for score architecture. > > - Continue discussing with UML for it. > Oh, sorry, I forgot, after remove IOMEM from kernel, also s390 and tile need implement dummy IOMEM if !PCI. If possible, I shall try to implement the dummy IOMEM in 'asm-generic', and let uml, score, s390 and tile use them when they need. > > By the way: how about HAS_DMA? can we treat it as HAS_IOMEM (remove > it from kernel)? (for me, I guess we can not). > > > At present, I shall finish sending patch for removing IOMEM today, and > continue to welcome any ideas, suggestions or completions for IOMEM or > DMA. > > Thanks. -- Chen Gang Open share and attitude like air water and life which God blessed -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
