On Sat, Jul 19, 2014 at 11:05:33AM +0200, Arnd Bergmann wrote: > On Saturday 19 July 2014 10:41:52 Sam Ravnborg wrote: > > > > > > > > This set: > > > > #define inb_p(addr) inb(addr) > > > > #define inw_p(addr) inw(addr) > > > > #define inl_p(addr) inl(addr) > > > > #define outb_p(x, addr) outb((x), (addr)) > > > > #define outw_p(x, addr) outw((x), (addr)) > > > > #define outl_p(x, addr) outl((x), (addr)) > > > > > > > > Should have a comment that say they are deprecated. > > > > Especially the "b" variants still have many users. > > > > > > Are they? I don't remember ever seeing a reason to deprecate > > > them. We could perhaps enclose them in #ifdef CONFIG_ISA, but > > > there may also be some drivers that use the same code for ISA > > > and PCI, and it doesn't really hurt on PCI. > > > > It is my understanding that inl and inl_p are the same these days. > > A quick grep indicate that only m68k define the > > _p variant different from the other. > > But I failed to find and description of the difference between the > > two which is why I assumed they were identical and thus no need for both. > > I don't know why m68k needs it, it's really an x86-specific > thing, see slow_down_io() in arch/x86/include/asm/io.h. I had missed the x86 versions when grepping. Hmm, and with the macro tricks they play in asm/io.h this file is not at all grep friendly. So xxx_p is for pause (or something like that). This also matches that m68k do some tricks with delay() in the _p variants. Thanks for the explanation. Sam -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
