On Sun, Oct 14, 2018 at 12:11 AM Christoph Hellwig <hch@xxxxxx> wrote: > > There is no good reason to duplicate the PCI menu in every architecture. > Instead provide a selectable HAS_PCI symbol that indicates availability > of PCI support and the handle the rest in drivers/pci. I think HAVE_ is a preferred prefix in this case according to this doc: https://github.com/masahir0y/linux/blob/v4.19-rc4/Documentation/kbuild/kconfig-language.txt#L448 It is true we have some options with HAS_ prefix, but the majority is HAVE_. masahiro@pug:~/ref/linux$ find . -name 'Kconfig*' | xargs grep 'config HAS_' | wc 9 18 355 masahiro@pug:~/ref/linux$ find . -name 'Kconfig*' | xargs grep 'config HAVE_' | wc 177 354 8182 > Note that for powerpc we now select HAS_PCI globally instead of the > convoluted mess of conditional or or non-conditional support per board, > similar to what we do e.g. on x86. For alpha PCI is selected for the > non-jensen configs as it was the default before, and a lot of code does > not compile without PCI enabled. On other architectures with limited > PCI support that wasn't as complicated I've left the selection as-is. > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > --- > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 6fa6f92edb7f..0713375e1127 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -168,10 +168,16 @@ config PPC > select GENERIC_CPU_VULNERABILITIES if PPC_BARRIER_NOSPEC > select GENERIC_IRQ_SHOW > select GENERIC_IRQ_SHOW_LEVEL > + select GENERIC_PCI_IOMAP if PCI > select GENERIC_SMP_IDLE_THREAD > select GENERIC_STRNCPY_FROM_USER > select GENERIC_STRNLEN_USER > select GENERIC_TIME_VSYSCALL > + # Platforms that what PCI turned unconditionally just do select PCI > + # in their config node, otherwise allow the user to enable it. > + # This means we can enable PCI even on platforms that don't support > + # it, which is harmless except for wasted memory. > + select HAS_PCI If you do this for entire powerpc, the other 'select HAS_PCI' addtions to arch/powerpc/platforms/*/Kconfig look redundant. > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index a344980287a5..6eb31a0698ac 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -38,6 +38,7 @@ config RISCV > select RISCV_ISA_A if SMP > select SPARSE_IRQ > select SYSCTL_EXCEPTION_TRACE > + select HAS_PCI > select HAVE_ARCH_TRACEHOOK > select MODULES_USE_ELF_RELA if MODULES > select THREAD_INFO_IN_TASK > @@ -216,28 +217,12 @@ source "kernel/Kconfig.hz" > > endmenu > > -menu "Bus support" > - > -config PCI > - bool "PCI support" > - select PCI_MSI I think this 'select PCI_MSI' for riscv was lost. > - help > - This feature enables support for PCI bus system. If you say Y > - here, the kernel will include drivers and infrastructure code > - to support PCI bus devices. > - > - If you don't know what to do here, say Y. > - > config PCI_DOMAINS > def_bool PCI > > config PCI_DOMAINS_GENERIC > def_bool PCI > > -source "drivers/pci/Kconfig" > - > -endmenu > - > menu "Power management options" > > source kernel/power/Kconfig > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 1a0be022f91d..7cbc656f47e7 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -113,6 +113,7 @@ config X86 > select GENERIC_STRNLEN_USER > select GENERIC_TIME_VSYSCALL > select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 > + select HAS_PCI > select HAVE_ACPI_APEI if ACPI > select HAVE_ACPI_APEI_NMI if ACPI > select HAVE_ALIGNED_STRUCT_PAGE if SLUB > @@ -2567,15 +2568,6 @@ endmenu > > menu "Bus options (PCI etc.)" > > -config PCI > - bool "PCI support" > - default y The default is y for x86 (and xtensa as well). With this patch, the default will be flipped. I think most of people want to use PCI for x86, and this change will make people upset. Will you update arch/{x86,xtensa}/configs/*_defconfig? > - ---help--- > - Find out whether you have a PCI motherboard. PCI is the name of a > - bus system, i.e. the way the CPU talks to the other stuff inside > - your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or > - VESA. If you have PCI, say Y, otherwise N. > - > choice > prompt "PCI access mode" > depends on X86_32 && PCI > @@ -2658,8 +2650,6 @@ config PCI_CNB20LE_QUIRK > > You should say N unless you know you need this. > > -source "drivers/pci/Kconfig" > - > config ISA_BUS > bool "ISA bus support on modern systems" if EXPERT > help > diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig > index b9ad83a0ee5d..22abeb236863 100644 > --- a/arch/xtensa/Kconfig > +++ b/arch/xtensa/Kconfig > @@ -20,6 +20,7 @@ config XTENSA > select GENERIC_PCI_IOMAP > select GENERIC_SCHED_CLOCK > select GENERIC_STRNCPY_FROM_USER if KASAN > + select HAS_PCI > select HAVE_ARCH_KASAN if MMU > select HAVE_DEBUG_KMEMLEAK > select HAVE_DMA_CONTIGUOUS > @@ -384,21 +385,6 @@ config XTENSA_CALIBRATE_CCOUNT > config SERIAL_CONSOLE > def_bool n > > -menu "Bus options" > - > -config PCI > - bool "PCI support" > - default y > - help > - Find out whether you have a PCI motherboard. PCI is the name of a > - bus system, i.e. the way the CPU talks to the other stuff inside > - your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or > - VESA. If you have PCI, say Y, otherwise N. > - > -source "drivers/pci/Kconfig" > - > -endmenu > - > menu "Platform options" > > choice > diff --git a/drivers/Kconfig b/drivers/Kconfig > index ab4d43923c4d..059573823387 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -1,7 +1,11 @@ > # SPDX-License-Identifier: GPL-2.0 > menu "Device Drivers" > > +# Keep I/O buses first > + > source "drivers/amba/Kconfig" > +source "drivers/pci/Kconfig" > + > > source "drivers/base/Kconfig" > > diff --git a/drivers/parisc/Kconfig b/drivers/parisc/Kconfig > index 5a48b5606110..5bbfea1a019c 100644 > --- a/drivers/parisc/Kconfig > +++ b/drivers/parisc/Kconfig > @@ -63,17 +63,6 @@ config ISA > If you want to plug an ISA card into your EISA bus, say Y here. > Most people should say N. > > -config PCI > - bool "PCI support" > - help > - All recent HP machines have PCI slots, and you should say Y here > - if you have a recent machine. If you are convinced you do not have > - PCI slots in your machine (eg a 712), then you may say "N" here. > - Beware that some GSC cards have a Dino onboard and PCI inside them, > - so it may be safest to say "Y" anyway. > - > -source "drivers/pci/Kconfig" > - > config GSC_DINO > bool "GSCtoPCI/Dino PCI support" > depends on PCI && GSC > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig > index 56ff8f6d31fc..229a518b68cd 100644 > --- a/drivers/pci/Kconfig > +++ b/drivers/pci/Kconfig > @@ -3,6 +3,18 @@ > # PCI configuration > # > > +config HAS_PCI > + bool > + > +menuconfig PCI > + bool "PCI support" > + depends on HAS_PCI > + > + help > + This option enables support for the PCI local bus, including > + support for PCI-X and the fundations for PCI Express support. > + Say 'Y' here unless you know what you are doing. > + > source "drivers/pci/pcie/Kconfig" > > config PCI_MSI > -- > 2.19.1 > -- Best Regards Masahiro Yamada
