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 HAVE_SETUP_PER_CPU_AREA
52 config STACKTRACE_SUPPORT
56 config HAVE_LATENCYTOP_SUPPORT
59 config TRACE_IRQFLAGS_SUPPORT
64 config LOCKDEP_SUPPORT
68 config RWSEM_GENERIC_SPINLOCK
71 config RWSEM_XCHGADD_ALGORITHM
75 config GENERIC_LOCKBREAK
78 depends on SMP && PREEMPT
80 config ARCH_HAS_ILOG2_U32
84 config ARCH_HAS_ILOG2_U64
88 config GENERIC_HWEIGHT
92 config GENERIC_CALIBRATE_DELAY
96 config GENERIC_FIND_NEXT_BIT
103 Generic GPIO API support
105 config ARCH_NO_VIRT_TO_BUS
111 select HAVE_FTRACE_MCOUNT_RECORD
112 select HAVE_DYNAMIC_FTRACE
113 select HAVE_FUNCTION_TRACER
114 select HAVE_FUNCTION_GRAPH_TRACER
115 select ARCH_WANT_OPTIONAL_GPIOLIB
117 select HAVE_IOREMAP_PROT
118 select HAVE_EFFICIENT_UNALIGNED_ACCESS
120 select HAVE_ARCH_KGDB
121 select HAVE_KRETPROBES
122 select HAVE_ARCH_TRACEHOOK
124 select HAVE_DMA_ATTRS if PPC64
125 select USE_GENERIC_SMP_HELPERS if SMP
127 select HAVE_SYSCALL_WRAPPERS if PPC64
136 select COMPAT_BINFMT_ELF
138 config SYSVIPC_COMPAT
140 depends on COMPAT && SYSVIPC
143 # All PPC32s use generic nvram driver through ppc_md
148 config SCHED_OMIT_FRAME_POINTER
152 config ARCH_MAY_HAVE_PC_FDC
154 default !PPC_PSERIES || PCI
162 config PPC_UDBG_16550
166 config GENERIC_TBSYNC
168 default y if PPC32 && SMP
180 config SYS_SUPPORTS_APM_EMULATION
181 default y if PMAC_APM_EMU
184 config DEFAULT_UIMAGE
187 Used to allow a board to specify it wants a uImage built by default
195 depends on (PPC_PMAC && !SMP) || BROKEN
200 depends on BROKEN || (PPC_PMAC64 && EXPERIMENTAL)
203 config ARCH_HIBERNATION_POSSIBLE
205 depends on (PPC64 && HIBERNATE_64) || (PPC32 && HIBERNATE_32)
208 config ARCH_SUSPEND_POSSIBLE
210 depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx
212 config PPC_DCR_NATIVE
222 depends on PPC_DCR_NATIVE || PPC_DCR_MMIO
225 config PPC_OF_PLATFORM_PCI
228 depends on PPC64 # not supported on 32 bits yet
231 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
234 source "init/Kconfig"
236 source "kernel/Kconfig.freezer"
238 source "arch/powerpc/sysdev/Kconfig"
239 source "arch/powerpc/platforms/Kconfig"
241 menu "Kernel options"
244 bool "High memory support"
247 source kernel/time/Kconfig
248 source kernel/Kconfig.hz
249 source kernel/Kconfig.preempt
250 source "fs/Kconfig.binfmt"
252 config HUGETLB_PAGE_SIZE_VARIABLE
254 depends on HUGETLB_PAGE
257 config MATH_EMULATION
258 bool "Math emulation"
259 depends on 4xx || 8xx || E200 || PPC_MPC832x || E500
261 Some PowerPC chips designed for embedded applications do not have
262 a floating-point unit and therefore do not implement the
263 floating-point instructions in the PowerPC instruction set. If you
264 say Y here, the kernel will include code to emulate a floating-point
265 unit, which will allow programs that use floating-point
268 config 8XX_MINIMAL_FPEMU
269 bool "Minimal math emulation for 8xx"
270 depends on 8xx && !MATH_EMULATION
272 Older arch/ppc kernels still emulated a few floating point
273 instructions such as load and store, even when full math
274 emulation is disabled. Say "Y" here if you want to preserve
277 It is recommended that you build a soft-float userspace instead.
280 bool "Enable IOMMU virtual merging"
284 Cause IO segments sent to a device for DMA to be merged virtually
285 by the IOMMU when they happen to have been allocated contiguously.
286 This doesn't add pressure to the IOMMU allocator. However, some
287 drivers don't support getting large merged segments coming back
290 Most drivers don't have this problem; it is safe to say Y here.
295 config PPC_NEED_DMA_SYNC_OPS
297 depends on NOT_COHERENT_CACHE
300 bool "Support for enabling/disabling CPUs"
301 depends on SMP && HOTPLUG && EXPERIMENTAL && (PPC_PSERIES || PPC_PMAC)
303 Say Y here to be able to disable and re-enable individual
304 CPUs at runtime on SMP machines.
306 Say N if you are unsure.
308 config ARCH_ENABLE_MEMORY_HOTPLUG
311 config ARCH_HAS_WALK_MEMORY
314 config ARCH_ENABLE_MEMORY_HOTREMOVE
318 bool "kexec system call (EXPERIMENTAL)"
319 depends on PPC_BOOK3S && EXPERIMENTAL
321 kexec is a system call that implements the ability to shutdown your
322 current kernel, and to start another kernel. It is like a reboot
323 but it is independent of the system firmware. And like a reboot
324 you can start any kernel with it, not just Linux.
326 The name comes from the similarity to the exec system call.
328 It is an ongoing process to be certain the hardware in a machine
329 is properly shutdown, so do not be surprised if this code does not
330 initially work for you. It may help to enable device hotplugging
331 support. As of this writing the exact hardware interface is
332 strongly in flux, so no good recommendation can be made.
335 bool "Build a kdump crash kernel"
336 depends on PPC64 || 6xx
337 select RELOCATABLE if PPC64
339 Build a kernel suitable for use as a kdump capture kernel.
340 The same kernel binary can be used as production kernel and dump
344 bool "Hypervisor-assisted dump (EXPERIMENTAL)"
345 depends on PPC_PSERIES && EXPERIMENTAL
347 Hypervisor-assisted dump is meant to be a kdump replacement
348 offering robustness and speed not possible without system
349 hypervisor assistance.
354 bool "Enable reading PPCBUG NVRAM during boot" if PPLUS || LOPEC
355 default y if PPC_PREP
358 bool "Distribute interrupts on all CPUs by default"
359 depends on SMP && !MV64360
361 This option gives the kernel permission to distribute IRQs across
362 multiple CPUs. Saying N here will route all IRQs to the first
363 CPU. Generally saying Y is safe, although some problems have been
364 reported with SMP Power Macintoshes with this option enabled.
369 default y if SMP && PPC_PSERIES
374 depends on NEED_MULTIPLE_NODES
376 config ARCH_SELECT_MEMORY_MODEL
380 config ARCH_FLATMEM_ENABLE
382 depends on (PPC64 && !NUMA) || PPC32
384 config ARCH_SPARSEMEM_ENABLE
387 select SPARSEMEM_VMEMMAP_ENABLE
389 config ARCH_SPARSEMEM_DEFAULT
391 depends on (SMP && PPC_PSERIES) || PPC_PS3
393 config ARCH_POPULATES_NODE_MAP
398 config ARCH_MEMORY_PROBE
400 depends on MEMORY_HOTPLUG
402 # Some NUMA nodes have memory ranges that span
403 # other nodes. Even though a pfn is valid and
404 # between a node's start and end pfns, it may not
405 # reside on that node. See memmap_init_zone()
407 config NODES_SPAN_OTHER_NODES
409 depends on NEED_MULTIPLE_NODES
411 config PPC_HAS_HASH_64K
417 bool "Using standard binutils settings"
421 Turning this option off allows you to select 256KB PAGE_SIZE on 44x.
422 Note, that kernel will be able to run only those applications,
423 which had been compiled using binutils later than 2.17.50.0.3 with
424 '-zmax-page-size' set to 256K (the default is 64K). Or, if using
425 the older binutils, you can patch them with a trivial patch, which
426 changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000.
432 Select the kernel logical page size. Increasing the page size
433 will reduce software overhead at each page boundary, allow
434 hardware prefetch mechanisms to be more effective, and allow
435 larger dma transfers increasing IO efficiency and reducing
436 overhead. However the utilization of memory will increase.
437 For example, each cached file will using a multiple of the
438 page size to hold its contents and the difference between the
439 end of file and the end of page is wasted.
441 Some dedicated systems, such as software raid serving with
442 accelerated calculations, have shown significant increases.
444 If you configure a 64 bit kernel for 64k pages but the
445 processor does not support them, then the kernel will simulate
446 them with 4k pages, loading them on demand, but with the
447 reduced software overhead and larger internal fragmentation.
448 For the 32 bit kernel, a large page option will not be offered
449 unless it is supported by the configured processor.
451 If unsure, choose 4K_PAGES.
457 bool "16k page size" if 44x
460 bool "64k page size" if 44x || PPC_STD_MMU_64
461 select PPC_HAS_HASH_64K if PPC_STD_MMU_64
463 config PPC_256K_PAGES
464 bool "256k page size" if 44x
465 depends on !STDBINUTILS
467 Make the page size 256k.
469 As the ELF standard only requires alignment to support page
470 sizes up to 64k, you will need to compile all of your user
471 space applications with a non-standard binutils settings
472 (see the STDBINUTILS description for details).
474 Say N unless you know what you are doing.
478 config FORCE_MAX_ZONEORDER
479 int "Maximum zone order"
480 range 9 64 if PPC_STD_MMU_64 && PPC_64K_PAGES
481 default "9" if PPC_STD_MMU_64 && PPC_64K_PAGES
482 range 13 64 if PPC_STD_MMU_64 && !PPC_64K_PAGES
483 default "13" if PPC_STD_MMU_64 && !PPC_64K_PAGES
484 range 9 64 if PPC_STD_MMU_32 && PPC_16K_PAGES
485 default "9" if PPC_STD_MMU_32 && PPC_16K_PAGES
486 range 7 64 if PPC_STD_MMU_32 && PPC_64K_PAGES
487 default "7" if PPC_STD_MMU_32 && PPC_64K_PAGES
488 range 5 64 if PPC_STD_MMU_32 && PPC_256K_PAGES
489 default "5" if PPC_STD_MMU_32 && PPC_256K_PAGES
493 The kernel memory allocator divides physically contiguous memory
494 blocks into "zones", where each zone is a power of two number of
495 pages. This option selects the largest power of two that the kernel
496 keeps in the memory allocator. If you need to allocate very large
497 blocks of physically contiguous memory, then you may need to
500 This config option is actually maximum order plus one. For example,
501 a value of 11 means that the largest free memory block is 2^10 pages.
503 The page size is not necessarily 4KB. For example, on 64-bit
504 systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep
505 this in mind when choosing a value for this option.
507 config PPC_SUBPAGE_PROT
508 bool "Support setting protections for 4k subpages"
509 depends on PPC_STD_MMU_64 && PPC_64K_PAGES
511 This option adds support for a system call to allow user programs
512 to set access permissions (read/write, readonly, or no access)
513 on the 4k subpages of each 64k page.
516 bool "SMT (Hyperthreading) scheduler support"
517 depends on PPC64 && SMP
519 SMT scheduler support improves the CPU scheduler's decision making
520 when dealing with POWER5 cpus at a cost of slightly increased
521 overhead in some places. If unsure say N here.
523 config PROC_DEVICETREE
524 bool "Support for device tree in /proc"
527 This option adds a device-tree directory under /proc which contains
528 an image of the device tree that the kernel copies from Open
529 Firmware or other boot firmware. If unsure, say Y here.
532 bool "Default bootloader kernel arguments"
535 string "Initial kernel command string"
536 depends on CMDLINE_BOOL
537 default "console=ttyS0,9600 console=tty0 root=/dev/sda2"
539 On some platforms, there is currently no way for the boot loader to
540 pass arguments to the kernel. For these platforms, you can supply
541 some command-line options at build time by entering them here. In
542 most cases you will need to specify the root device here.
545 string "Additional default image types"
547 List additional targets to be built by the bootwrapper here (separated
548 by spaces). This is useful for targets that depend of device tree
549 files in the .dts directory.
551 Targets in this list will be build as part of the default build
552 target, or when the user does a 'make zImage' or a
553 'make zImage.initrd'.
555 If unsure, leave blank
558 config ARCH_WANTS_FREEZER_CONTROL
562 source kernel/power/Kconfig
566 bool "Enable seccomp to safely compute untrusted bytecode"
570 This kernel feature is useful for number crunching applications
571 that may need to compute untrusted bytecode during their
572 execution. By using pipes or other transports made available to
573 the process as file descriptors supporting the read/write
574 syscalls, it's possible to isolate those applications in
575 their own address space using seccomp. Once seccomp is
576 enabled via /proc/<pid>/seccomp, it cannot be disabled
577 and the task is only allowed to execute a few safe syscalls
578 defined by each seccomp mode.
580 If unsure, say Y. Only embedded should say N here.
586 default !PPC_ISERIES || PCI
591 bool "Support for ISA-bus hardware"
592 depends on PPC_PREP || PPC_CHRP
595 Find out whether you have ISA slots on your motherboard. ISA is the
596 name of a bus system, i.e. the way the CPU talks to the other stuff
597 inside your box. If you have an Apple machine, say N here; if you
598 have an IBM RS/6000 or pSeries machine or a PReP machine, say Y. If
599 you have an embedded board, consult your board documentation.
605 config GENERIC_ISA_DMA
607 depends on PPC64 || POWER4 || 6xx && !CPM2
610 config PPC_INDIRECT_PCI
613 default y if 40x || 44x
627 select PPC_INDIRECT_PCI
636 Freescale Localbus support
640 depends on PPC_83xx || QUICC_ENGINE || CPM2
642 Freescale General-purpose Timers support
644 # Yes MCA RS/6000s exist but Linux-PPC does not currently support any
648 # Platforms that what PCI turned unconditionally just do select PCI
649 # in their config node. Platforms that want to choose at config
650 # time should select PPC_PCI_CHOICE
651 config PPC_PCI_CHOICE
655 bool "PCI support" if PPC_PCI_CHOICE
656 default y if !40x && !CPM2 && !8xx && !PPC_83xx \
657 && !PPC_85xx && !PPC_86xx
658 default PCI_PERMEDIA if !4xx && !CPM2 && !8xx
659 default PCI_QSPAN if !4xx && !CPM2 && 8xx
660 select ARCH_SUPPORTS_MSI
662 Find out whether your system includes a PCI bus. PCI is the name of
663 a bus system, i.e. the way the CPU talks to the other stuff inside
664 your box. If you say Y here, the kernel will include drivers and
665 infrastructure code to support PCI bus devices.
675 depends on !4xx && !CPM2 && 8xx
678 Say Y here if you have a system based on a Motorola 8xx-series
679 embedded processor with a QSPAN PCI interface, otherwise say N.
683 depends on PCI && 8260
684 select PPC_INDIRECT_PCI
688 bool "Enable workaround for MPC826x erratum PCI 9"
689 depends on PCI_8260 && !8272
693 prompt "IDMA channel for PCI 9 workaround"
696 config 8260_PCI9_IDMA1
699 config 8260_PCI9_IDMA2
702 config 8260_PCI9_IDMA3
705 config 8260_PCI9_IDMA4
710 source "drivers/pci/pcie/Kconfig"
712 source "drivers/pci/Kconfig"
714 source "drivers/pcmcia/Kconfig"
716 source "drivers/pci/hotplug/Kconfig"
723 bool "RapidIO support"
724 depends on HAS_RAPIDIO
726 If you say Y here, the kernel will include drivers and
727 infrastructure code to support RapidIO interconnect devices.
729 source "drivers/rapidio/Kconfig"
733 menu "Advanced setup"
736 config ADVANCED_OPTIONS
737 bool "Prompt for advanced kernel configuration options"
739 This option will enable prompting for a variety of advanced kernel
740 configuration options. These options can cause the kernel to not
741 work if they are set incorrectly, but can be used to optimize certain
742 aspects of kernel memory management.
744 Unless you know what you are doing, say N here.
746 comment "Default settings for advanced configuration options are used"
747 depends on !ADVANCED_OPTIONS
749 config LOWMEM_SIZE_BOOL
750 bool "Set maximum low memory"
751 depends on ADVANCED_OPTIONS
753 This option allows you to set the maximum amount of memory which
754 will be used as "low memory", that is, memory which the kernel can
755 access directly, without having to set up a kernel virtual mapping.
756 This can be useful in optimizing the layout of kernel virtual
759 Say N here unless you know what you are doing.
762 hex "Maximum low memory size (in bytes)" if LOWMEM_SIZE_BOOL
765 config LOWMEM_CAM_NUM_BOOL
766 bool "Set number of CAMs to use to map low memory"
767 depends on ADVANCED_OPTIONS && FSL_BOOKE
769 This option allows you to set the maximum number of CAM slots that
770 will be used to map low memory. There are a limited number of slots
771 available and even more limited number that will fit in the L1 MMU.
772 However, using more entries will allow mapping more low memory. This
773 can be useful in optimizing the layout of kernel virtual memory.
775 Say N here unless you know what you are doing.
777 config LOWMEM_CAM_NUM
779 int "Number of CAMs to use to map low memory" if LOWMEM_CAM_NUM_BOOL
783 bool "Build a relocatable kernel (EXPERIMENTAL)"
784 depends on EXPERIMENTAL && ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
786 This builds a kernel image that is capable of running at the
787 location the kernel is loaded at (some alignment restrictions may
790 One use is for the kexec on panic case where the recovery kernel
791 must live at a different physical address than the primary
794 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
795 it has been loaded at and the compile time physical addresses
796 CONFIG_PHYSICAL_START is ignored. However CONFIG_PHYSICAL_START
797 setting can still be useful to bootwrappers that need to know the
798 load location of the kernel (eg. u-boot/mkimage).
800 config PAGE_OFFSET_BOOL
801 bool "Set custom page offset address"
802 depends on ADVANCED_OPTIONS
804 This option allows you to set the kernel virtual address at which
805 the kernel will map low memory. This can be useful in optimizing
806 the virtual memory layout of the system.
808 Say N here unless you know what you are doing.
811 hex "Virtual address of memory base" if PAGE_OFFSET_BOOL
814 config KERNEL_START_BOOL
815 bool "Set custom kernel base address"
816 depends on ADVANCED_OPTIONS
818 This option allows you to set the kernel virtual address at which
819 the kernel will be loaded. Normally this should match PAGE_OFFSET
820 however there are times (like kdump) that one might not want them
823 Say N here unless you know what you are doing.
826 hex "Virtual address of kernel base" if KERNEL_START_BOOL
827 default PAGE_OFFSET if PAGE_OFFSET_BOOL
828 default "0xc2000000" if CRASH_DUMP
831 config PHYSICAL_START_BOOL
832 bool "Set physical address where the kernel is loaded"
833 depends on ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
835 This gives the physical address where the kernel is loaded.
837 Say N here unless you know what you are doing.
839 config PHYSICAL_START
840 hex "Physical address where the kernel is loaded" if PHYSICAL_START_BOOL
841 default "0x02000000" if PPC_STD_MMU && CRASH_DUMP
844 config PHYSICAL_ALIGN
846 default "0x04000000" if FSL_BOOKE
848 This value puts the alignment restrictions on physical address
849 where kernel is loaded and run from. Kernel is compiled for an
850 address which meets above alignment restriction.
852 config TASK_SIZE_BOOL
853 bool "Set custom user task size"
854 depends on ADVANCED_OPTIONS
856 This option allows you to set the amount of virtual address space
857 allocated to user tasks. This can be useful in optimizing the
858 virtual memory layout of the system.
860 Say N here unless you know what you are doing.
863 hex "Size of user task space" if TASK_SIZE_BOOL
864 default "0x80000000" if PPC_PREP || PPC_8xx
868 bool "Pinned Kernel TLBs (860 ONLY)"
869 depends on ADVANCED_OPTIONS && 8xx
874 bool "Build a relocatable kernel"
876 This builds a kernel image that is capable of running anywhere
877 in the RMA (real memory area) at any 16k-aligned base address.
878 The kernel is linked as a position-independent executable (PIE)
879 and contains dynamic relocations which are processed early
880 in the bootup process.
882 One use is for the kexec on panic case where the recovery kernel
883 must live at a different physical address than the primary
888 default "0xc000000000000000"
891 default "0xc000000000000000"
892 config PHYSICAL_START
899 source "drivers/Kconfig"
903 source "arch/powerpc/sysdev/qe_lib/Kconfig"
907 source "arch/powerpc/Kconfig.debug"
909 source "security/Kconfig"
913 depends on COMPAT && KEYS
916 source "crypto/Kconfig"
926 source "arch/powerpc/kvm/Kconfig"