1 # For a description of the syntax of this configuration file,
2 # see Documentation/kbuild/kconfig-language.txt.
5 mainmenu "Linux/PowerPC Kernel Configuration"
7 source "arch/powerpc/platforms/Kconfig.cputype"
22 config ARCH_PHYS_ADDR_T_64BIT
23 def_bool PPC64 || PHYS_64BIT
29 config GENERIC_CMOS_UPDATE
35 config GENERIC_TIME_VSYSCALL
38 config GENERIC_CLOCKEVENTS
41 config GENERIC_HARDIRQS
45 config GENERIC_HARDIRQS_NO__DO_IRQ
49 config HAVE_SETUP_PER_CPU_AREA
52 config NEED_PER_CPU_EMBED_FIRST_CHUNK
60 int "Number of virtual interrupt numbers"
64 This defines the number of virtual interrupt numbers the kernel
65 can manage. Virtual interrupt numbers are what you see in
66 /proc/interrupts. If you configure your system to have too few,
67 drivers will fail to load or worse - handle with care.
69 config STACKTRACE_SUPPORT
73 config HAVE_LATENCYTOP_SUPPORT
76 config TRACE_IRQFLAGS_SUPPORT
80 config LOCKDEP_SUPPORT
84 config RWSEM_GENERIC_SPINLOCK
87 config RWSEM_XCHGADD_ALGORITHM
91 config GENERIC_LOCKBREAK
94 depends on SMP && PREEMPT
96 config ARCH_HAS_ILOG2_U32
100 config ARCH_HAS_ILOG2_U64
104 config GENERIC_HWEIGHT
108 config GENERIC_FIND_NEXT_BIT
115 Generic GPIO API support
117 config ARCH_NO_VIRT_TO_BUS
123 select HAVE_FTRACE_MCOUNT_RECORD
124 select HAVE_DYNAMIC_FTRACE
125 select HAVE_FUNCTION_TRACER
126 select HAVE_FUNCTION_GRAPH_TRACER
127 select ARCH_WANT_OPTIONAL_GPIOLIB
129 select HAVE_IOREMAP_PROT
130 select HAVE_EFFICIENT_UNALIGNED_ACCESS
132 select HAVE_ARCH_KGDB
133 select HAVE_KRETPROBES
134 select HAVE_ARCH_TRACEHOOK
136 select HAVE_DMA_ATTRS
137 select HAVE_DMA_API_DEBUG
138 select USE_GENERIC_SMP_HELPERS if SMP
140 select HAVE_SYSCALL_WRAPPERS if PPC64
141 select GENERIC_ATOMIC64 if PPC32
142 select HAVE_PERF_EVENTS
151 select COMPAT_BINFMT_ELF
153 config SYSVIPC_COMPAT
155 depends on COMPAT && SYSVIPC
158 # All PPC32s use generic nvram driver through ppc_md
163 config SCHED_OMIT_FRAME_POINTER
167 config ARCH_MAY_HAVE_PC_FDC
169 default !PPC_PSERIES || PCI
177 config PPC_UDBG_16550
181 config GENERIC_TBSYNC
183 default y if PPC32 && SMP
195 config SYS_SUPPORTS_APM_EMULATION
196 default y if PMAC_APM_EMU
203 config DEFAULT_UIMAGE
206 Used to allow a board to specify it wants a uImage built by default
212 config ARCH_HIBERNATION_POSSIBLE
216 config ARCH_SUSPEND_POSSIBLE
218 depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx
220 config PPC_DCR_NATIVE
230 depends on PPC_DCR_NATIVE || PPC_DCR_MMIO
233 config PPC_OF_PLATFORM_PCI
236 depends on PPC64 # not supported on 32 bits yet
239 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
242 source "init/Kconfig"
244 source "kernel/Kconfig.freezer"
246 source "arch/powerpc/sysdev/Kconfig"
247 source "arch/powerpc/platforms/Kconfig"
249 menu "Kernel options"
252 bool "High memory support"
255 source kernel/time/Kconfig
256 source kernel/Kconfig.hz
257 source kernel/Kconfig.preempt
258 source "fs/Kconfig.binfmt"
260 config HUGETLB_PAGE_SIZE_VARIABLE
262 depends on HUGETLB_PAGE
265 config MATH_EMULATION
266 bool "Math emulation"
267 depends on 4xx || 8xx || E200 || PPC_MPC832x || E500
269 Some PowerPC chips designed for embedded applications do not have
270 a floating-point unit and therefore do not implement the
271 floating-point instructions in the PowerPC instruction set. If you
272 say Y here, the kernel will include code to emulate a floating-point
273 unit, which will allow programs that use floating-point
276 config 8XX_MINIMAL_FPEMU
277 bool "Minimal math emulation for 8xx"
278 depends on 8xx && !MATH_EMULATION
280 Older arch/ppc kernels still emulated a few floating point
281 instructions such as load and store, even when full math
282 emulation is disabled. Say "Y" here if you want to preserve
285 It is recommended that you build a soft-float userspace instead.
288 bool "Enable IOMMU virtual merging"
292 Cause IO segments sent to a device for DMA to be merged virtually
293 by the IOMMU when they happen to have been allocated contiguously.
294 This doesn't add pressure to the IOMMU allocator. However, some
295 drivers don't support getting large merged segments coming back
298 Most drivers don't have this problem; it is safe to say Y here.
304 bool "SWIOTLB support"
308 Support for IO bounce buffering for systems without an IOMMU.
309 This allows us to DMA to the full physical address space on
310 platforms where the size of a physical address is larger
311 than the bus address. Not all platforms support this.
314 bool "Support for enabling/disabling CPUs"
315 depends on SMP && HOTPLUG && EXPERIMENTAL && (PPC_PSERIES || PPC_PMAC)
317 Say Y here to be able to disable and re-enable individual
318 CPUs at runtime on SMP machines.
320 Say N if you are unsure.
322 config ARCH_ENABLE_MEMORY_HOTPLUG
325 config ARCH_HAS_WALK_MEMORY
328 config ARCH_ENABLE_MEMORY_HOTREMOVE
332 bool "kexec system call (EXPERIMENTAL)"
333 depends on PPC_BOOK3S && EXPERIMENTAL
335 kexec is a system call that implements the ability to shutdown your
336 current kernel, and to start another kernel. It is like a reboot
337 but it is independent of the system firmware. And like a reboot
338 you can start any kernel with it, not just Linux.
340 The name comes from the similarity to the exec system call.
342 It is an ongoing process to be certain the hardware in a machine
343 is properly shutdown, so do not be surprised if this code does not
344 initially work for you. It may help to enable device hotplugging
345 support. As of this writing the exact hardware interface is
346 strongly in flux, so no good recommendation can be made.
349 bool "Build a kdump crash kernel"
350 depends on PPC64 || 6xx
351 select RELOCATABLE if PPC64
353 Build a kernel suitable for use as a kdump capture kernel.
354 The same kernel binary can be used as production kernel and dump
358 bool "Hypervisor-assisted dump (EXPERIMENTAL)"
359 depends on PPC_PSERIES && EXPERIMENTAL
361 Hypervisor-assisted dump is meant to be a kdump replacement
362 offering robustness and speed not possible without system
363 hypervisor assistance.
368 bool "Enable reading PPCBUG NVRAM during boot" if PPLUS || LOPEC
369 default y if PPC_PREP
372 bool "Distribute interrupts on all CPUs by default"
373 depends on SMP && !MV64360
375 This option gives the kernel permission to distribute IRQs across
376 multiple CPUs. Saying N here will route all IRQs to the first
377 CPU. Generally saying Y is safe, although some problems have been
378 reported with SMP Power Macintoshes with this option enabled.
381 bool "Support sparse irq numbering"
384 This enables support for sparse irqs. This is useful for distro
385 kernels that want to define a high CONFIG_NR_CPUS value but still
386 want to have low kernel memory footprint on smaller machines.
388 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
389 out the irq_desc[] array in a more NUMA-friendly way. )
391 If you don't know what to do here, say Y.
396 default y if SMP && PPC_PSERIES
402 depends on NEED_MULTIPLE_NODES
404 config MAX_ACTIVE_REGIONS
406 default "256" if PPC64
409 config ARCH_SELECT_MEMORY_MODEL
413 config ARCH_FLATMEM_ENABLE
415 depends on (PPC64 && !NUMA) || PPC32
417 config ARCH_SPARSEMEM_ENABLE
420 select SPARSEMEM_VMEMMAP_ENABLE
422 config ARCH_SPARSEMEM_DEFAULT
424 depends on (SMP && PPC_PSERIES) || PPC_PS3
426 config ARCH_POPULATES_NODE_MAP
429 config SYS_SUPPORTS_HUGETLBFS
431 depends on PPC_BOOK3S_64
435 config ARCH_MEMORY_PROBE
437 depends on MEMORY_HOTPLUG
439 # Some NUMA nodes have memory ranges that span
440 # other nodes. Even though a pfn is valid and
441 # between a node's start and end pfns, it may not
442 # reside on that node. See memmap_init_zone()
444 config NODES_SPAN_OTHER_NODES
446 depends on NEED_MULTIPLE_NODES
448 config PPC_HAS_HASH_64K
454 bool "Using standard binutils settings"
458 Turning this option off allows you to select 256KB PAGE_SIZE on 44x.
459 Note, that kernel will be able to run only those applications,
460 which had been compiled using binutils later than 2.17.50.0.3 with
461 '-zmax-page-size' set to 256K (the default is 64K). Or, if using
462 the older binutils, you can patch them with a trivial patch, which
463 changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000.
469 Select the kernel logical page size. Increasing the page size
470 will reduce software overhead at each page boundary, allow
471 hardware prefetch mechanisms to be more effective, and allow
472 larger dma transfers increasing IO efficiency and reducing
473 overhead. However the utilization of memory will increase.
474 For example, each cached file will using a multiple of the
475 page size to hold its contents and the difference between the
476 end of file and the end of page is wasted.
478 Some dedicated systems, such as software raid serving with
479 accelerated calculations, have shown significant increases.
481 If you configure a 64 bit kernel for 64k pages but the
482 processor does not support them, then the kernel will simulate
483 them with 4k pages, loading them on demand, but with the
484 reduced software overhead and larger internal fragmentation.
485 For the 32 bit kernel, a large page option will not be offered
486 unless it is supported by the configured processor.
488 If unsure, choose 4K_PAGES.
494 bool "16k page size" if 44x
497 bool "64k page size" if 44x || PPC_STD_MMU_64 || PPC_BOOK3E_64
498 select PPC_HAS_HASH_64K if PPC_STD_MMU_64
500 config PPC_256K_PAGES
501 bool "256k page size" if 44x
502 depends on !STDBINUTILS
504 Make the page size 256k.
506 As the ELF standard only requires alignment to support page
507 sizes up to 64k, you will need to compile all of your user
508 space applications with a non-standard binutils settings
509 (see the STDBINUTILS description for details).
511 Say N unless you know what you are doing.
515 config FORCE_MAX_ZONEORDER
516 int "Maximum zone order"
517 range 9 64 if PPC64 && PPC_64K_PAGES
518 default "9" if PPC64 && PPC_64K_PAGES
519 range 13 64 if PPC64 && !PPC_64K_PAGES
520 default "13" if PPC64 && !PPC_64K_PAGES
521 range 9 64 if PPC32 && PPC_16K_PAGES
522 default "9" if PPC32 && PPC_16K_PAGES
523 range 7 64 if PPC32 && PPC_64K_PAGES
524 default "7" if PPC32 && PPC_64K_PAGES
525 range 5 64 if PPC32 && PPC_256K_PAGES
526 default "5" if PPC32 && PPC_256K_PAGES
530 The kernel memory allocator divides physically contiguous memory
531 blocks into "zones", where each zone is a power of two number of
532 pages. This option selects the largest power of two that the kernel
533 keeps in the memory allocator. If you need to allocate very large
534 blocks of physically contiguous memory, then you may need to
537 This config option is actually maximum order plus one. For example,
538 a value of 11 means that the largest free memory block is 2^10 pages.
540 The page size is not necessarily 4KB. For example, on 64-bit
541 systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep
542 this in mind when choosing a value for this option.
544 config PPC_SUBPAGE_PROT
545 bool "Support setting protections for 4k subpages"
546 depends on PPC_STD_MMU_64 && PPC_64K_PAGES
548 This option adds support for a system call to allow user programs
549 to set access permissions (read/write, readonly, or no access)
550 on the 4k subpages of each 64k page.
553 bool "SMT (Hyperthreading) scheduler support"
554 depends on PPC64 && SMP
556 SMT scheduler support improves the CPU scheduler's decision making
557 when dealing with POWER5 cpus at a cost of slightly increased
558 overhead in some places. If unsure say N here.
560 config PROC_DEVICETREE
561 bool "Support for device tree in /proc"
564 This option adds a device-tree directory under /proc which contains
565 an image of the device tree that the kernel copies from Open
566 Firmware or other boot firmware. If unsure, say Y here.
569 bool "Default bootloader kernel arguments"
572 string "Initial kernel command string"
573 depends on CMDLINE_BOOL
574 default "console=ttyS0,9600 console=tty0 root=/dev/sda2"
576 On some platforms, there is currently no way for the boot loader to
577 pass arguments to the kernel. For these platforms, you can supply
578 some command-line options at build time by entering them here. In
579 most cases you will need to specify the root device here.
582 string "Additional default image types"
584 List additional targets to be built by the bootwrapper here (separated
585 by spaces). This is useful for targets that depend of device tree
586 files in the .dts directory.
588 Targets in this list will be build as part of the default build
589 target, or when the user does a 'make zImage' or a
590 'make zImage.initrd'.
592 If unsure, leave blank
595 config ARCH_WANTS_FREEZER_CONTROL
599 source kernel/power/Kconfig
603 bool "Enable seccomp to safely compute untrusted bytecode"
607 This kernel feature is useful for number crunching applications
608 that may need to compute untrusted bytecode during their
609 execution. By using pipes or other transports made available to
610 the process as file descriptors supporting the read/write
611 syscalls, it's possible to isolate those applications in
612 their own address space using seccomp. Once seccomp is
613 enabled via /proc/<pid>/seccomp, it cannot be disabled
614 and the task is only allowed to execute a few safe syscalls
615 defined by each seccomp mode.
617 If unsure, say Y. Only embedded should say N here.
623 default !PPC_ISERIES || PCI
628 bool "Support for ISA-bus hardware"
629 depends on PPC_PREP || PPC_CHRP
632 Find out whether you have ISA slots on your motherboard. ISA is the
633 name of a bus system, i.e. the way the CPU talks to the other stuff
634 inside your box. If you have an Apple machine, say N here; if you
635 have an IBM RS/6000 or pSeries machine or a PReP machine, say Y. If
636 you have an embedded board, consult your board documentation.
642 config GENERIC_ISA_DMA
644 depends on PPC64 || POWER4 || 6xx && !CPM2
647 config PPC_INDIRECT_PCI
650 default y if 40x || 44x
664 select PPC_INDIRECT_PCI
673 Freescale Localbus support
677 depends on PPC_83xx || QUICC_ENGINE || CPM2
679 Freescale General-purpose Timers support
681 # Yes MCA RS/6000s exist but Linux-PPC does not currently support any
685 # Platforms that what PCI turned unconditionally just do select PCI
686 # in their config node. Platforms that want to choose at config
687 # time should select PPC_PCI_CHOICE
688 config PPC_PCI_CHOICE
692 bool "PCI support" if PPC_PCI_CHOICE
693 default y if !40x && !CPM2 && !8xx && !PPC_83xx \
694 && !PPC_85xx && !PPC_86xx
695 default PCI_PERMEDIA if !4xx && !CPM2 && !8xx
696 default PCI_QSPAN if !4xx && !CPM2 && 8xx
697 select ARCH_SUPPORTS_MSI
699 Find out whether your system includes a PCI bus. PCI is the name of
700 a bus system, i.e. the way the CPU talks to the other stuff inside
701 your box. If you say Y here, the kernel will include drivers and
702 infrastructure code to support PCI bus devices.
712 depends on !4xx && !CPM2 && 8xx
715 Say Y here if you have a system based on a Motorola 8xx-series
716 embedded processor with a QSPAN PCI interface, otherwise say N.
720 depends on PCI && 8260
721 select PPC_INDIRECT_PCI
725 bool "Enable workaround for MPC826x erratum PCI 9"
726 depends on PCI_8260 && !8272
730 prompt "IDMA channel for PCI 9 workaround"
733 config 8260_PCI9_IDMA1
736 config 8260_PCI9_IDMA2
739 config 8260_PCI9_IDMA3
742 config 8260_PCI9_IDMA4
747 source "drivers/pci/pcie/Kconfig"
749 source "drivers/pci/Kconfig"
751 source "drivers/pcmcia/Kconfig"
753 source "drivers/pci/hotplug/Kconfig"
760 bool "RapidIO support"
761 depends on HAS_RAPIDIO
763 If you say Y here, the kernel will include drivers and
764 infrastructure code to support RapidIO interconnect devices.
766 source "drivers/rapidio/Kconfig"
770 menu "Advanced setup"
773 config ADVANCED_OPTIONS
774 bool "Prompt for advanced kernel configuration options"
776 This option will enable prompting for a variety of advanced kernel
777 configuration options. These options can cause the kernel to not
778 work if they are set incorrectly, but can be used to optimize certain
779 aspects of kernel memory management.
781 Unless you know what you are doing, say N here.
783 comment "Default settings for advanced configuration options are used"
784 depends on !ADVANCED_OPTIONS
786 config LOWMEM_SIZE_BOOL
787 bool "Set maximum low memory"
788 depends on ADVANCED_OPTIONS
790 This option allows you to set the maximum amount of memory which
791 will be used as "low memory", that is, memory which the kernel can
792 access directly, without having to set up a kernel virtual mapping.
793 This can be useful in optimizing the layout of kernel virtual
796 Say N here unless you know what you are doing.
799 hex "Maximum low memory size (in bytes)" if LOWMEM_SIZE_BOOL
802 config LOWMEM_CAM_NUM_BOOL
803 bool "Set number of CAMs to use to map low memory"
804 depends on ADVANCED_OPTIONS && FSL_BOOKE
806 This option allows you to set the maximum number of CAM slots that
807 will be used to map low memory. There are a limited number of slots
808 available and even more limited number that will fit in the L1 MMU.
809 However, using more entries will allow mapping more low memory. This
810 can be useful in optimizing the layout of kernel virtual memory.
812 Say N here unless you know what you are doing.
814 config LOWMEM_CAM_NUM
816 int "Number of CAMs to use to map low memory" if LOWMEM_CAM_NUM_BOOL
820 bool "Build a relocatable kernel (EXPERIMENTAL)"
821 depends on EXPERIMENTAL && ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
823 This builds a kernel image that is capable of running at the
824 location the kernel is loaded at (some alignment restrictions may
827 One use is for the kexec on panic case where the recovery kernel
828 must live at a different physical address than the primary
831 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
832 it has been loaded at and the compile time physical addresses
833 CONFIG_PHYSICAL_START is ignored. However CONFIG_PHYSICAL_START
834 setting can still be useful to bootwrappers that need to know the
835 load location of the kernel (eg. u-boot/mkimage).
837 config PAGE_OFFSET_BOOL
838 bool "Set custom page offset address"
839 depends on ADVANCED_OPTIONS
841 This option allows you to set the kernel virtual address at which
842 the kernel will map low memory. This can be useful in optimizing
843 the virtual memory layout of the system.
845 Say N here unless you know what you are doing.
848 hex "Virtual address of memory base" if PAGE_OFFSET_BOOL
851 config KERNEL_START_BOOL
852 bool "Set custom kernel base address"
853 depends on ADVANCED_OPTIONS
855 This option allows you to set the kernel virtual address at which
856 the kernel will be loaded. Normally this should match PAGE_OFFSET
857 however there are times (like kdump) that one might not want them
860 Say N here unless you know what you are doing.
863 hex "Virtual address of kernel base" if KERNEL_START_BOOL
864 default PAGE_OFFSET if PAGE_OFFSET_BOOL
865 default "0xc2000000" if CRASH_DUMP
868 config PHYSICAL_START_BOOL
869 bool "Set physical address where the kernel is loaded"
870 depends on ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
872 This gives the physical address where the kernel is loaded.
874 Say N here unless you know what you are doing.
876 config PHYSICAL_START
877 hex "Physical address where the kernel is loaded" if PHYSICAL_START_BOOL
878 default "0x02000000" if PPC_STD_MMU && CRASH_DUMP
881 config PHYSICAL_ALIGN
883 default "0x04000000" if FSL_BOOKE
885 This value puts the alignment restrictions on physical address
886 where kernel is loaded and run from. Kernel is compiled for an
887 address which meets above alignment restriction.
889 config TASK_SIZE_BOOL
890 bool "Set custom user task size"
891 depends on ADVANCED_OPTIONS
893 This option allows you to set the amount of virtual address space
894 allocated to user tasks. This can be useful in optimizing the
895 virtual memory layout of the system.
897 Say N here unless you know what you are doing.
900 hex "Size of user task space" if TASK_SIZE_BOOL
901 default "0x80000000" if PPC_PREP || PPC_8xx
904 config CONSISTENT_SIZE_BOOL
905 bool "Set custom consistent memory pool size"
906 depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE
908 This option allows you to set the size of the
909 consistent memory pool. This pool of virtual memory
910 is used to make consistent memory allocations.
912 config CONSISTENT_SIZE
913 hex "Size of consistent memory pool" if CONSISTENT_SIZE_BOOL
914 default "0x00200000" if NOT_COHERENT_CACHE
917 bool "Pinned Kernel TLBs (860 ONLY)"
918 depends on ADVANCED_OPTIONS && 8xx
923 bool "Build a relocatable kernel"
925 This builds a kernel image that is capable of running anywhere
926 in the RMA (real memory area) at any 16k-aligned base address.
927 The kernel is linked as a position-independent executable (PIE)
928 and contains dynamic relocations which are processed early
929 in the bootup process.
931 One use is for the kexec on panic case where the recovery kernel
932 must live at a different physical address than the primary
937 default "0xc000000000000000"
940 default "0xc000000000000000"
941 config PHYSICAL_START
948 source "drivers/Kconfig"
952 source "arch/powerpc/sysdev/qe_lib/Kconfig"
956 source "arch/powerpc/Kconfig.debug"
958 source "security/Kconfig"
962 depends on COMPAT && KEYS
965 source "crypto/Kconfig"
975 source "arch/powerpc/kvm/Kconfig"