diff mbox series

[v3,01/38] Kconfig: introduce HAS_IOPORT option and select it as necessary

Message ID 20230314121216.413434-2-schnelle@linux.ibm.com (mailing list archive)
State Superseded
Headers show
Series [v3,01/38] Kconfig: introduce HAS_IOPORT option and select it as necessary | expand

Commit Message

Niklas Schnelle March 14, 2023, 12:11 p.m. UTC
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.

Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
 arch/alpha/Kconfig      | 1 +
 arch/arm/Kconfig        | 1 +
 arch/arm64/Kconfig      | 1 +
 arch/ia64/Kconfig       | 1 +
 arch/m68k/Kconfig       | 1 +
 arch/microblaze/Kconfig | 1 +
 arch/mips/Kconfig       | 2 ++
 arch/parisc/Kconfig     | 2 ++
 arch/powerpc/Kconfig    | 2 +-
 arch/riscv/Kconfig      | 1 +
 arch/sh/Kconfig         | 1 +
 arch/sparc/Kconfig      | 1 +
 arch/um/Kconfig         | 1 +
 arch/x86/Kconfig        | 2 ++
 drivers/bus/Kconfig     | 2 +-
 drivers/eisa/Kconfig    | 1 +
 lib/Kconfig             | 4 ++++
 lib/Kconfig.kgdb        | 3 ++-
 18 files changed, 25 insertions(+), 3 deletions(-)

Comments

Niklas Schnelle March 14, 2023, 4:11 p.m. UTC | #1
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@kernel.org>
> > Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
> 
> 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
Niklas Schnelle March 14, 2023, 4:37 p.m. UTC | #2
On Tue, 2023-03-14 at 13:11 +0100, 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.
> 
> Co-developed-by: Arnd Bergmann <arnd@kernel.org>
> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
> ---
> 

@Arnd, I swear I asked you and then added Signed-off-bys for all these
Co-developed-bys as suggested by checkpatch. Sadly that must have been
during my failed attempt of converting to b4 prep / b4 send before
sending this last Friday and then it got lost. It almost worked and is
a very nice work flow except that b4 currently can only use a single
list of To/Cc fields and for this treewide series that would probably
hit mail server limits. Added it now.

Thanks,
Niklas
Niklas Schnelle March 23, 2023, 1:23 p.m. UTC | #3
On Tue, 2023-03-14 at 13:37 +0100, Johannes Berg wrote:
> On Tue, 2023-03-14 at 13:11 +0100, Niklas Schnelle wrote:
> > --- a/arch/um/Kconfig
> > +++ b/arch/um/Kconfig
> > @@ -56,6 +56,7 @@ config NO_IOPORT_MAP
> >  
> >  config ISA
> >  	bool
> > +	depends on HAS_IOPORT
> > 
> 
> config ISA here is already unselectable, and nothing ever does "select
> ISA" (only in some other architectures), so is there much point in this?
> 
> I'm not even sure why this exists at all.

You're right there's not much point and I dropped this for v4. I agree
that probably the whole "config ISA" could be removed if it's always
false anyway but that seems out of scope for this patch.

> 
> But anyway, adding a dependency to a always-false symbol doesn't make it
> less always-false :-)
> 
> Acked-by: Johannes Berg <johannes@sipsolutions.net> # for ARCH=um

Thanks

> 
> 
> Certainly will be nice to get rid of this cruft for architectures that
> don't have it.
> 
> johannes

Yes, also, for s390 the broken NULL + port number access in the generic
inb()/outb() currently causes the only remaining clang warning on
defconfig builds.
diff mbox series

Patch

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 780d4673c3ca..a5c2b1aa46b0 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -27,6 +27,7 @@  config ALPHA
 	select AUDIT_ARCH
 	select GENERIC_CPU_VULNERABILITIES
 	select GENERIC_SMP_IDLE_THREAD
+	select HAS_IOPORT
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_MOD_ARCH_SPECIFIC
 	select MODULES_USE_ELF_RELA
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e24a9820e12f..4acb5bc4b52a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -70,6 +70,7 @@  config ARM
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select HARDIRQS_SW_RESEND
+	select HAS_IOPORT
 	select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1023e896d46b..b740019c4aee 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -145,6 +145,7 @@  config ARM64
 	select GENERIC_GETTIMEOFDAY
 	select GENERIC_VDSO_TIME_NS
 	select HARDIRQS_SW_RESEND
+	select HAS_IOPORT
 	select HAVE_MOVE_PMD
 	select HAVE_MOVE_PUD
 	select HAVE_PCI
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index d7e4a24e8644..2e13ec8263b9 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -25,6 +25,7 @@  config IA64
 	select PCI_DOMAINS if PCI
 	select PCI_MSI
 	select PCI_SYSCALL if PCI
+	select HAS_IOPORT
 	select HAVE_ASM_MODVERSIONS
 	select HAVE_UNSTABLE_SCHED_CLOCK
 	select HAVE_EXIT_THREAD
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 82154952e574..40198a1ebe27 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -18,6 +18,7 @@  config M68K
 	select GENERIC_CPU_DEVICES
 	select GENERIC_IOMAP
 	select GENERIC_IRQ_SHOW
+	select HAS_IOPORT if PCI || ISA || ATARI_ROM_ISA
 	select HAVE_ARCH_SECCOMP
 	select HAVE_ARCH_SECCOMP_FILTER
 	select HAVE_ASM_MODVERSIONS
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index cc88af6fa7a4..211f338d6235 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -21,6 +21,7 @@  config MICROBLAZE
 	select GENERIC_IRQ_SHOW
 	select GENERIC_PCI_IOMAP
 	select GENERIC_SCHED_CLOCK
+	select HAS_IOPORT if PCI
 	select HAVE_ARCH_HASH
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_SECCOMP
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index e2f3ca73f40d..64760fcd7b52 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -47,6 +47,7 @@  config MIPS
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select GUP_GET_PXX_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT
+	select HAS_IOPORT if !NO_IOPORT_MAP
 	select HAVE_ARCH_COMPILER_H
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KGDB if MIPS_FP_SUPPORT
@@ -3120,6 +3121,7 @@  config PCI_DRIVERS_LEGACY
 # users to choose the right thing ...
 #
 config ISA
+	depends on HAS_IOPORT
 	bool
 
 config TC
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
 	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
 
 config ARCH_MAY_HAVE_PC_FDC
 	bool
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
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index c5e42cc37604..b957d12a171b 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -74,6 +74,7 @@  config RISCV
 	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
 	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
 	select HARDIRQS_SW_RESEND
+	select HAS_IOPORT if MMU
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
 	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 0665ac0add0b..cfb797bc4200 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -25,6 +25,7 @@  config SUPERH
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select GUP_GET_PXX_LOW_HIGH if X2TLB
+	select HAS_IOPORT if HAS_IOPORT_MAP
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_SECCOMP_FILTER
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 84437a4c6545..d4c1d96f85cd 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -32,6 +32,7 @@  config SPARC
 	select GENERIC_IRQ_SHOW
 	select ARCH_WANT_IPC_PARSE_VERSION
 	select GENERIC_PCI_IOMAP
+	select HAS_IOPORT
 	select HAVE_NMI_WATCHDOG if SPARC64
 	select HAVE_CBPF_JIT if SPARC32
 	select HAVE_EBPF_JIT if SPARC64
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 541a9b18e343..452d268be2e8 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -56,6 +56,7 @@  config NO_IOPORT_MAP
 
 config ISA
 	bool
+	depends on HAS_IOPORT
 
 config SBUS
 	bool
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
 	  Find out whether you have ISA slots on your motherboard.  ISA is the
 	  name of a bus system, i.e. the way the CPU talks to the other stuff
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 7bfe998f3514..fcfa280df98a 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -81,7 +81,7 @@  config MOXTET
 config HISILICON_LPC
 	bool "Support for ISA I/O space on HiSilicon Hip06/7"
 	depends on (ARM64 && ARCH_HISI) || (COMPILE_TEST && !ALPHA && !HEXAGON && !PARISC)
-	depends on HAS_IOMEM
+	depends on HAS_IOPORT
 	select INDIRECT_PIO if ARM64
 	help
 	  Driver to enable I/O access to devices attached to the Low Pin
diff --git a/drivers/eisa/Kconfig b/drivers/eisa/Kconfig
index c8bbf90209f5..d3f62de72259 100644
--- a/drivers/eisa/Kconfig
+++ b/drivers/eisa/Kconfig
@@ -5,6 +5,7 @@ 
 
 config HAVE_EISA
 	bool
+	depends on HAS_IOPORT
 
 menuconfig EISA
 	bool "EISA support"
diff --git a/lib/Kconfig b/lib/Kconfig
index ce2abffb9ed8..5c2da561c516 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -92,6 +92,7 @@  config ARCH_USE_SYM_ANNOTATIONS
 config INDIRECT_PIO
 	bool "Access I/O in non-MMIO mode"
 	depends on ARM64
+	depends on HAS_IOPORT
 	help
 	  On some platforms where no separate I/O space exists, there are I/O
 	  hosts which can not be accessed in MMIO mode. Using the logical PIO
@@ -509,6 +510,9 @@  config HAS_IOMEM
 	depends on !NO_IOMEM
 	default y
 
+config HAS_IOPORT
+	bool
+
 config HAS_IOPORT_MAP
 	bool
 	depends on HAS_IOMEM && !NO_IOPORT_MAP
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
 	help
 	  KDB can use a PS/2 type keyboard for an input device