On Tue, 2023-03-14 at 14:29 +0100, Arnd Bergmann wrote: > On Tue, Mar 14, 2023, at 13:11, Niklas Schnelle wrote: > > We introduce a new HAS_IOPORT Kconfig option to indicate support for I/O > > Port access. In a future patch HAS_IOPORT=n will disable compilation of > > the I/O accessor functions inb()/outb() and friends on architectures > > which can not meaningfully support legacy I/O spaces such as s390. Also > > add dependencies on HAS_IOPORT for the ISA and HAVE_EISA config options > > as these busses always go along with HAS_IOPORT. > > > > The "depends on" relations on HAS_IOPORT in drivers as well as ifdefs > > for HAS_IOPORT specific sections will be added in subsequent patches on > > a per subsystem basis. > > I think it would be helpful to enumerate which architectures > do not get HAS_IOPORT added, as they will be affected more. > > > Co-developed-by: Arnd Bergmann <arnd@xxxxxxxxxx> > > Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> > > If there are no objections, I could send this first patch for the > asm-generic tree as a preparation for 6.3, so we are able to merge > the other patches through subsystem maintainer tree for 6.4. > > arch/loongarch/ will now also need to select HAS_IOPORT > uncontitionally, this architecture was added after you > sent v2. Ah right. Added "select HAS_IOPORT" for LoongArch. > > > diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig > > index a98940e64243..5eeacc72e4da 100644 > > --- a/arch/parisc/Kconfig > > +++ b/arch/parisc/Kconfig > > @@ -47,6 +47,7 @@ config PARISC > > select MODULES_USE_ELF_RELA > > select CLONE_BACKWARDS > > select TTY # Needed for pdc_cons.c > > + select HAS_IOPORT if PCI > > It's also needed for EISA and I think you should select it > from CONFIG_GSC in drivers/parisc/Kconfig for this purpose. > > This could also be 'select HAS_IOPORT if PCI || EISA', but > that would require removing the 'depends on HAS_IOPORT' > under drivers/eisa/. I did use "select HAS_IOPORT if PCI || ISA || ATARI_ROM_ISA" in m68k so I think ideally we would handle both in the same way. I don't have a strong preference but I think the "select HAS_IOPORT if ..." puts it all in a single place which is nice. Also I think this would make it more similar architectures with unconditional HAS_IOPORT that thus don't need "depends on HAS_IOPORT" in their "config ISA" either. As also pointed by your comment below for x86. So will try to go this route. > > > select HAVE_DEBUG_STACKOVERFLOW > > select HAVE_ARCH_AUDITSYSCALL > > select HAVE_ARCH_HASH > > @@ -131,6 +132,7 @@ config STACKTRACE_SUPPORT > > > > config ISA_DMA_API > > bool > > + depends on HAS_IOPORT > > > > This line is not really needed since there is no way to > enable ISA_DMA_API. Removed > > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > > index a6c4407d3ec8..f7de646c074a 100644 > > --- a/arch/powerpc/Kconfig > > +++ b/arch/powerpc/Kconfig > > @@ -188,6 +188,7 @@ config PPC > > select GENERIC_SMP_IDLE_THREAD > > select GENERIC_TIME_VSYSCALL > > select GENERIC_VDSO_TIME_NS > > + select HAS_IOPORT if PCI > > select HAVE_ARCH_AUDITSYSCALL > > select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP > > select HAVE_ARCH_HUGE_VMAP if PPC_RADIX_MMU || PPC_8xx > > @@ -1070,7 +1071,6 @@ menu "Bus options" > > > > config ISA > > bool "Support for ISA-bus hardware" > > - depends on PPC_CHRP > > select PPC_I8259 > > help > > Find out whether you have ISA slots on your motherboard. ISA is the > > This line looks wrong, I think we should keep that dependency. > Did you get a circular dependency if you leave it in? I don't recall why this was removed. I guess it happened when I was experimenting with adding "depends on HAS_IOPORT" for the ISA config options but that ultimately lead to circular dependencies, must have messed up when removing this here. > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index a825bf031f49..634dd42532f3 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -162,6 +162,7 @@ config X86 > > select GUP_GET_PXX_LOW_HIGH if X86_PAE > > select HARDIRQS_SW_RESEND > > select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 > > + select HAS_IOPORT > > select HAVE_ACPI_APEI if ACPI > > select HAVE_ACPI_APEI_NMI if ACPI > > select HAVE_ALIGNED_STRUCT_PAGE if SLUB > > @@ -2893,6 +2894,7 @@ if X86_32 > > > > config ISA > > bool "ISA support" > > + depends on HAS_IOPORT > > help > > HAS_IOPORT is selected unconditionally already, so this doesn't > really do anything. Removed. > > > diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb > > index 3b9a44008433..c68e4d9dcecb 100644 > > --- a/lib/Kconfig.kgdb > > +++ b/lib/Kconfig.kgdb > > @@ -121,7 +121,8 @@ config KDB_DEFAULT_ENABLE > > > > config KDB_KEYBOARD > > bool "KGDB_KDB: keyboard as input device" > > - depends on VT && KGDB_KDB && !PARISC > > + depends on HAS_IOPORT > > + depends on VT && KGDB_KDB > > default n > > This loses the !PARISC dependency, which I don't think is > intentional. The added HAS_IOPORT dependency makes sense > here, but I think this should be in a different patch > and not in the preparation. > > Arnd Agree will put into its own patch and re-add the !PARISC