arch/powerpc/Kconfig

   1 source "arch/powerpc/platforms/Kconfig.cputype"
   2
   3 config PPC32
   4         bool
   5         default y if !PPC64
   6
   7 config 32BIT
   8         bool
   9         default y if PPC32
  10
  11 config 64BIT
  12         bool
  13         default y if PPC64
  14
  15 config ARCH_PHYS_ADDR_T_64BIT
  16        def_bool PPC64 || PHYS_64BIT
  17
  18 config ARCH_DMA_ADDR_T_64BIT
  19         def_bool ARCH_PHYS_ADDR_T_64BIT
  20
  21 config MMU
  22         bool
  23         default y
  24
  25 config HAVE_SETUP_PER_CPU_AREA
  26         def_bool PPC64
  27
  28 config NEED_PER_CPU_EMBED_FIRST_CHUNK
  29         def_bool PPC64
  30
  31 config NR_IRQS
  32         int "Number of virtual interrupt numbers"
  33         range 32 32768
  34         default "512"
  35         help
  36           This defines the number of virtual interrupt numbers the kernel
  37           can manage. Virtual interrupt numbers are what you see in
  38           /proc/interrupts. If you configure your system to have too few,
  39           drivers will fail to load or worse - handle with care.
  40
  41 config STACKTRACE_SUPPORT
  42         bool
  43         default y
  44
  45 config TRACE_IRQFLAGS_SUPPORT
  46         bool
  47         default y
  48
  49 config LOCKDEP_SUPPORT
  50         bool
  51         default y
  52
  53 config RWSEM_GENERIC_SPINLOCK
  54         bool
  55
  56 config RWSEM_XCHGADD_ALGORITHM
  57         bool
  58         default y
  59
  60 config GENERIC_LOCKBREAK
  61         bool
  62         default y
  63         depends on SMP && PREEMPT
  64
  65 config ARCH_HAS_ILOG2_U32
  66         bool
  67         default y
  68
  69 config ARCH_HAS_ILOG2_U64
  70         bool
  71         default y if 64BIT
  72
  73 config GENERIC_HWEIGHT
  74         bool
  75         default y
  76
  77 config ARCH_HAS_DMA_SET_COHERENT_MASK
  78         bool
  79
  80 config PPC
  81         bool
  82         default y
  83         select ARCH_MIGHT_HAVE_PC_PARPORT
  84         select ARCH_MIGHT_HAVE_PC_SERIO
  85         select BINFMT_ELF
  86         select ARCH_HAS_ELF_RANDOMIZE
  87         select OF
  88         select OF_EARLY_FLATTREE
  89         select OF_RESERVED_MEM
  90         select HAVE_FTRACE_MCOUNT_RECORD
  91         select HAVE_DYNAMIC_FTRACE
  92         select HAVE_DYNAMIC_FTRACE_WITH_REGS if MPROFILE_KERNEL
  93         select HAVE_FUNCTION_TRACER
  94         select HAVE_FUNCTION_GRAPH_TRACER
  95         select SYSCTL_EXCEPTION_TRACE
  96         select VIRT_TO_BUS if !PPC64
  97         select HAVE_IDE
  98         select HAVE_IOREMAP_PROT
  99         select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU)
 100         select HAVE_KPROBES
 101         select HAVE_ARCH_KGDB
 102         select HAVE_KRETPROBES
 103         select HAVE_ARCH_TRACEHOOK
 104         select HAVE_MEMBLOCK
 105         select HAVE_MEMBLOCK_NODE_MAP
 106         select HAVE_DMA_API_DEBUG
 107         select HAVE_OPROFILE
 108         select HAVE_DEBUG_KMEMLEAK
 109         select ARCH_HAS_SG_CHAIN
 110         select GENERIC_ATOMIC64 if PPC32
 111         select HAVE_PERF_EVENTS
 112         select HAVE_PERF_REGS
 113         select HAVE_PERF_USER_STACK_DUMP
 114         select HAVE_REGS_AND_STACK_ACCESS_API
 115         select HAVE_HW_BREAKPOINT if PERF_EVENTS && PPC_BOOK3S_64
 116         select ARCH_WANT_IPC_PARSE_VERSION
 117         select SPARSE_IRQ
 118         select IRQ_DOMAIN
 119         select GENERIC_IRQ_SHOW
 120         select GENERIC_IRQ_SHOW_LEVEL
 121         select IRQ_FORCED_THREADING
 122         select HAVE_RCU_TABLE_FREE if SMP
 123         select HAVE_SYSCALL_TRACEPOINTS
 124         select HAVE_CBPF_JIT if !PPC64
 125         select HAVE_EBPF_JIT if PPC64
 126         select HAVE_ARCH_JUMP_LABEL
 127         select ARCH_HAVE_NMI_SAFE_CMPXCHG
 128         select ARCH_HAS_GCOV_PROFILE_ALL
 129         select GENERIC_SMP_IDLE_THREAD
 130         select GENERIC_CMOS_UPDATE
 131         select GENERIC_TIME_VSYSCALL_OLD
 132         select GENERIC_CLOCKEVENTS
 133         select GENERIC_CLOCKEVENTS_BROADCAST if SMP
 134         select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 135         select GENERIC_STRNCPY_FROM_USER
 136         select GENERIC_STRNLEN_USER
 137         select HAVE_MOD_ARCH_SPECIFIC
 138         select MODULES_USE_ELF_RELA
 139         select CLONE_BACKWARDS
 140         select ARCH_USE_BUILTIN_BSWAP
 141         select OLD_SIGSUSPEND
 142         select OLD_SIGACTION if PPC32
 143         select HAVE_DEBUG_STACKOVERFLOW
 144         select HAVE_IRQ_EXIT_ON_IRQ_STACK
 145         select ARCH_USE_CMPXCHG_LOCKREF if PPC64
 146         select HAVE_ARCH_AUDITSYSCALL
 147         select ARCH_SUPPORTS_ATOMIC_RMW
 148         select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN
 149         select NO_BOOTMEM
 150         select HAVE_GENERIC_RCU_GUP
 151         select HAVE_PERF_EVENTS_NMI if PPC64
 152         select HAVE_NMI if PERF_EVENTS
 153         select EDAC_SUPPORT
 154         select EDAC_ATOMIC_SCRUB
 155         select ARCH_HAS_DMA_SET_COHERENT_MASK
 156         select ARCH_HAS_DEVMEM_IS_ALLOWED
 157         select HAVE_ARCH_SECCOMP_FILTER
 158         select ARCH_HAS_UBSAN_SANITIZE_ALL
 159         select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
 160         select HAVE_LIVEPATCH if HAVE_DYNAMIC_FTRACE_WITH_REGS
 161         select GENERIC_CPU_AUTOPROBE
 162         select HAVE_VIRT_CPU_ACCOUNTING
 163         select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE
 164         select HAVE_ARCH_HARDENED_USERCOPY
 165         select HAVE_KERNEL_GZIP
 166
 167 config GENERIC_CSUM
 168         def_bool CPU_LITTLE_ENDIAN
 169
 170 config EARLY_PRINTK
 171         bool
 172         default y
 173
 174 config PANIC_TIMEOUT
 175         int
 176         default 180
 177
 178 config COMPAT
 179         bool
 180         default y if PPC64
 181         select COMPAT_BINFMT_ELF
 182         select ARCH_WANT_OLD_COMPAT_IPC
 183         select COMPAT_OLD_SIGACTION
 184
 185 config SYSVIPC_COMPAT
 186         bool
 187         depends on COMPAT && SYSVIPC
 188         default y
 189
 190 # All PPC32s use generic nvram driver through ppc_md
 191 config GENERIC_NVRAM
 192         bool
 193         default y if PPC32
 194
 195 config SCHED_OMIT_FRAME_POINTER
 196         bool
 197         default y
 198
 199 config ARCH_MAY_HAVE_PC_FDC
 200         bool
 201         default PCI
 202
 203 config PPC_UDBG_16550
 204         bool
 205         default n
 206
 207 config GENERIC_TBSYNC
 208         bool
 209         default y if PPC32 && SMP
 210         default n
 211
 212 config AUDIT_ARCH
 213         bool
 214         default y
 215
 216 config GENERIC_BUG
 217         bool
 218         default y
 219         depends on BUG
 220
 221 config SYS_SUPPORTS_APM_EMULATION
 222         default y if PMAC_APM_EMU
 223         bool
 224
 225 config EPAPR_BOOT
 226         bool
 227         help
 228           Used to allow a board to specify it wants an ePAPR compliant wrapper.
 229         default n
 230
 231 config DEFAULT_UIMAGE
 232         bool
 233         help
 234           Used to allow a board to specify it wants a uImage built by default
 235         default n
 236
 237 config ARCH_HIBERNATION_POSSIBLE
 238         bool
 239         default y
 240
 241 config ARCH_SUSPEND_POSSIBLE
 242         def_bool y
 243         depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx || \
 244                    (PPC_85xx && !PPC_E500MC) || PPC_86xx || PPC_PSERIES \
 245                    || 44x || 40x
 246
 247 config PPC_DCR_NATIVE
 248         bool
 249         default n
 250
 251 config PPC_DCR_MMIO
 252         bool
 253         default n
 254
 255 config PPC_DCR
 256         bool
 257         depends on PPC_DCR_NATIVE || PPC_DCR_MMIO
 258         default y
 259
 260 config PPC_OF_PLATFORM_PCI
 261         bool
 262         depends on PCI
 263         depends on PPC64 # not supported on 32 bits yet
 264         default n
 265
 266 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 267         depends on PPC32 || PPC_STD_MMU_64
 268         def_bool y
 269
 270 config ARCH_SUPPORTS_UPROBES
 271         def_bool y
 272
 273 config PPC_ADV_DEBUG_REGS
 274         bool
 275         depends on 40x || BOOKE
 276         default y
 277
 278 config PPC_ADV_DEBUG_IACS
 279         int
 280         depends on PPC_ADV_DEBUG_REGS
 281         default 4 if 44x
 282         default 2
 283
 284 config PPC_ADV_DEBUG_DACS
 285         int
 286         depends on PPC_ADV_DEBUG_REGS
 287         default 2
 288
 289 config PPC_ADV_DEBUG_DVCS
 290         int
 291         depends on PPC_ADV_DEBUG_REGS
 292         default 2 if 44x
 293         default 0
 294
 295 config PPC_ADV_DEBUG_DAC_RANGE
 296         bool
 297         depends on PPC_ADV_DEBUG_REGS && 44x
 298         default y
 299
 300 config PPC_EMULATE_SSTEP
 301         bool
 302         default y if KPROBES || UPROBES || XMON || HAVE_HW_BREAKPOINT
 303
 304 config ZONE_DMA32
 305         bool
 306         default y if PPC64
 307
 308 config PGTABLE_LEVELS
 309         int
 310         default 2 if !PPC64
 311         default 3 if PPC_64K_PAGES && !PPC_BOOK3S_64
 312         default 4
 313
 314 source "init/Kconfig"
 315
 316 source "kernel/Kconfig.freezer"
 317
 318 source "arch/powerpc/sysdev/Kconfig"
 319 source "arch/powerpc/platforms/Kconfig"
 320
 321 menu "Kernel options"
 322
 323 config HIGHMEM
 324         bool "High memory support"
 325         depends on PPC32
 326
 327 source kernel/Kconfig.hz
 328 source kernel/Kconfig.preempt
 329 source "fs/Kconfig.binfmt"
 330
 331 config HUGETLB_PAGE_SIZE_VARIABLE
 332         bool
 333         depends on HUGETLB_PAGE
 334         default y
 335
 336 config MATH_EMULATION
 337         bool "Math emulation"
 338         depends on 4xx || 8xx || PPC_MPC832x || BOOKE
 339         ---help---
 340           Some PowerPC chips designed for embedded applications do not have
 341           a floating-point unit and therefore do not implement the
 342           floating-point instructions in the PowerPC instruction set.  If you
 343           say Y here, the kernel will include code to emulate a floating-point
 344           unit, which will allow programs that use floating-point
 345           instructions to run.
 346
 347           This is also useful to emulate missing (optional) instructions
 348           such as fsqrt on cores that do have an FPU but do not implement
 349           them (such as Freescale BookE).
 350
 351 choice
 352         prompt "Math emulation options"
 353         default MATH_EMULATION_FULL
 354         depends on MATH_EMULATION
 355
 356 config  MATH_EMULATION_FULL
 357         bool "Emulate all the floating point instructions"
 358         ---help---
 359           Select this option will enable the kernel to support to emulate
 360           all the floating point instructions. If your SoC doesn't have
 361           a FPU, you should select this.
 362
 363 config MATH_EMULATION_HW_UNIMPLEMENTED
 364         bool "Just emulate the FPU unimplemented instructions"
 365         ---help---
 366           Select this if you know there does have a hardware FPU on your
 367           SoC, but some floating point instructions are not implemented by that.
 368
 369 endchoice
 370
 371 config PPC_TRANSACTIONAL_MEM
 372        bool "Transactional Memory support for POWERPC"
 373        depends on PPC_BOOK3S_64
 374        depends on SMP
 375        select ALTIVEC
 376        select VSX
 377        default n
 378        ---help---
 379          Support user-mode Transactional Memory on POWERPC.
 380
 381 config DISABLE_MPROFILE_KERNEL
 382         bool "Disable use of mprofile-kernel for kernel tracing"
 383         depends on PPC64 && CPU_LITTLE_ENDIAN
 384         default y
 385         help
 386           Selecting this options disables use of the mprofile-kernel ABI for
 387           kernel tracing. That will cause options such as live patching
 388           (CONFIG_LIVEPATCH) which depend on CONFIG_DYNAMIC_FTRACE_WITH_REGS to
 389           be disabled also.
 390
 391           If you have a toolchain which supports mprofile-kernel, then you can
 392           enable this. Otherwise leave it disabled. If you're not sure, say
 393           "N".
 394
 395 config MPROFILE_KERNEL
 396         depends on PPC64 && CPU_LITTLE_ENDIAN
 397         def_bool !DISABLE_MPROFILE_KERNEL
 398
 399 config IOMMU_HELPER
 400         def_bool PPC64
 401
 402 config SWIOTLB
 403         bool "SWIOTLB support"
 404         default n
 405         select IOMMU_HELPER
 406         ---help---
 407           Support for IO bounce buffering for systems without an IOMMU.
 408           This allows us to DMA to the full physical address space on
 409           platforms where the size of a physical address is larger
 410           than the bus address.  Not all platforms support this.
 411
 412 config HOTPLUG_CPU
 413         bool "Support for enabling/disabling CPUs"
 414         depends on SMP && (PPC_PSERIES || \
 415         PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE)
 416         ---help---
 417           Say Y here to be able to disable and re-enable individual
 418           CPUs at runtime on SMP machines.
 419
 420           Say N if you are unsure.
 421
 422 config ARCH_CPU_PROBE_RELEASE
 423         def_bool y
 424         depends on HOTPLUG_CPU
 425
 426 config ARCH_ENABLE_MEMORY_HOTPLUG
 427         def_bool y
 428
 429 config ARCH_HAS_WALK_MEMORY
 430         def_bool y
 431
 432 config ARCH_ENABLE_MEMORY_HOTREMOVE
 433         def_bool y
 434
 435 config PPC64_SUPPORTS_MEMORY_FAILURE
 436         bool "Add support for memory hwpoison"
 437         depends on PPC_BOOK3S_64
 438         default "y" if PPC_POWERNV
 439         select ARCH_SUPPORTS_MEMORY_FAILURE
 440
 441 config KEXEC
 442         bool "kexec system call"
 443         depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP)) || PPC_BOOK3E
 444         select KEXEC_CORE
 445         help
 446           kexec is a system call that implements the ability to shutdown your
 447           current kernel, and to start another kernel.  It is like a reboot
 448           but it is independent of the system firmware.   And like a reboot
 449           you can start any kernel with it, not just Linux.
 450
 451           The name comes from the similarity to the exec system call.
 452
 453           It is an ongoing process to be certain the hardware in a machine
 454           is properly shutdown, so do not be surprised if this code does not
 455           initially work for you.  As of this writing the exact hardware
 456           interface is strongly in flux, so no good recommendation can be
 457           made.
 458
 459 config RELOCATABLE
 460         bool "Build a relocatable kernel"
 461         depends on (PPC64 && !COMPILE_TEST) || (FLATMEM && (44x || FSL_BOOKE))
 462         select NONSTATIC_KERNEL
 463         help
 464           This builds a kernel image that is capable of running at the
 465           location the kernel is loaded at. For ppc32, there is no any
 466           alignment restrictions, and this feature is a superset of
 467           DYNAMIC_MEMSTART and hence overrides it. For ppc64, we should use
 468           16k-aligned base address. The kernel is linked as a
 469           position-independent executable (PIE) and contains dynamic relocations
 470           which are processed early in the bootup process.
 471
 472           One use is for the kexec on panic case where the recovery kernel
 473           must live at a different physical address than the primary
 474           kernel.
 475
 476           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
 477           it has been loaded at and the compile time physical addresses
 478           CONFIG_PHYSICAL_START is ignored.  However CONFIG_PHYSICAL_START
 479           setting can still be useful to bootwrappers that need to know the
 480           load address of the kernel (eg. u-boot/mkimage).
 481
 482 config CRASH_DUMP
 483         bool "Build a kdump crash kernel"
 484         depends on PPC64 || 6xx || FSL_BOOKE || (44x && !SMP)
 485         select RELOCATABLE if (PPC64 && !COMPILE_TEST) || 44x || FSL_BOOKE
 486         help
 487           Build a kernel suitable for use as a kdump capture kernel.
 488           The same kernel binary can be used as production kernel and dump
 489           capture kernel.
 490
 491 config FA_DUMP
 492         bool "Firmware-assisted dump"
 493         depends on PPC64 && PPC_RTAS && CRASH_DUMP && KEXEC
 494         help
 495           A robust mechanism to get reliable kernel crash dump with
 496           assistance from firmware. This approach does not use kexec,
 497           instead firmware assists in booting the kdump kernel
 498           while preserving memory contents. Firmware-assisted dump
 499           is meant to be a kdump replacement offering robustness and
 500           speed not possible without system firmware assistance.
 501
 502           If unsure, say "N"
 503
 504 config IRQ_ALL_CPUS
 505         bool "Distribute interrupts on all CPUs by default"
 506         depends on SMP
 507         help
 508           This option gives the kernel permission to distribute IRQs across
 509           multiple CPUs.  Saying N here will route all IRQs to the first
 510           CPU.  Generally saying Y is safe, although some problems have been
 511           reported with SMP Power Macintoshes with this option enabled.
 512
 513 config NUMA
 514         bool "NUMA support"
 515         depends on PPC64
 516         default y if SMP && PPC_PSERIES
 517
 518 config NODES_SHIFT
 519         int
 520         default "8" if PPC64
 521         default "4"
 522         depends on NEED_MULTIPLE_NODES
 523
 524 config USE_PERCPU_NUMA_NODE_ID
 525         def_bool y
 526         depends on NUMA
 527
 528 config HAVE_MEMORYLESS_NODES
 529         def_bool y
 530         depends on NUMA
 531
 532 config ARCH_SELECT_MEMORY_MODEL
 533         def_bool y
 534         depends on PPC64
 535
 536 config ARCH_FLATMEM_ENABLE
 537         def_bool y
 538         depends on (PPC64 && !NUMA) || PPC32
 539
 540 config ARCH_SPARSEMEM_ENABLE
 541         def_bool y
 542         depends on PPC64
 543         select SPARSEMEM_VMEMMAP_ENABLE
 544
 545 config ARCH_SPARSEMEM_DEFAULT
 546         def_bool y
 547         depends on (SMP && PPC_PSERIES) || PPC_PS3
 548
 549 config SYS_SUPPORTS_HUGETLBFS
 550         bool
 551
 552 source "mm/Kconfig"
 553
 554 config ARCH_MEMORY_PROBE
 555         def_bool y
 556         depends on MEMORY_HOTPLUG
 557
 558 # Some NUMA nodes have memory ranges that span
 559 # other nodes.  Even though a pfn is valid and
 560 # between a node's start and end pfns, it may not
 561 # reside on that node.  See memmap_init_zone()
 562 # for details.
 563 config NODES_SPAN_OTHER_NODES
 564         def_bool y
 565         depends on NEED_MULTIPLE_NODES
 566
 567 config STDBINUTILS
 568         bool "Using standard binutils settings"
 569         depends on 44x
 570         default y
 571         help
 572           Turning this option off allows you to select 256KB PAGE_SIZE on 44x.
 573           Note, that kernel will be able to run only those applications,
 574           which had been compiled using binutils later than 2.17.50.0.3 with
 575           '-zmax-page-size' set to 256K (the default is 64K). Or, if using
 576           the older binutils, you can patch them with a trivial patch, which
 577           changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000.
 578
 579 choice
 580         prompt "Page size"
 581         default PPC_4K_PAGES
 582         help
 583           Select the kernel logical page size. Increasing the page size
 584           will reduce software overhead at each page boundary, allow
 585           hardware prefetch mechanisms to be more effective, and allow
 586           larger dma transfers increasing IO efficiency and reducing
 587           overhead. However the utilization of memory will increase.
 588           For example, each cached file will using a multiple of the
 589           page size to hold its contents and the difference between the
 590           end of file and the end of page is wasted.
 591
 592           Some dedicated systems, such as software raid serving with
 593           accelerated calculations, have shown significant increases.
 594
 595           If you configure a 64 bit kernel for 64k pages but the
 596           processor does not support them, then the kernel will simulate
 597           them with 4k pages, loading them on demand, but with the
 598           reduced software overhead and larger internal fragmentation.
 599           For the 32 bit kernel, a large page option will not be offered
 600           unless it is supported by the configured processor.
 601
 602           If unsure, choose 4K_PAGES.
 603
 604 config PPC_4K_PAGES
 605         bool "4k page size"
 606         select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
 607
 608 config PPC_16K_PAGES
 609         bool "16k page size"
 610         depends on 44x || PPC_8xx
 611
 612 config PPC_64K_PAGES
 613         bool "64k page size"
 614         depends on !PPC_FSL_BOOK3E && (44x || PPC_STD_MMU_64 || PPC_BOOK3E_64)
 615         select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
 616
 617 config PPC_256K_PAGES
 618         bool "256k page size"
 619         depends on 44x && !STDBINUTILS
 620         help
 621           Make the page size 256k.
 622
 623           As the ELF standard only requires alignment to support page
 624           sizes up to 64k, you will need to compile all of your user
 625           space applications with a non-standard binutils settings
 626           (see the STDBINUTILS description for details).
 627
 628           Say N unless you know what you are doing.
 629
 630 endchoice
 631
 632 config FORCE_MAX_ZONEORDER
 633         int "Maximum zone order"
 634         range 8 9 if PPC64 && PPC_64K_PAGES
 635         default "9" if PPC64 && PPC_64K_PAGES
 636         range 13 13 if PPC64 && !PPC_64K_PAGES
 637         default "13" if PPC64 && !PPC_64K_PAGES
 638         range 9 64 if PPC32 && PPC_16K_PAGES
 639         default "9" if PPC32 && PPC_16K_PAGES
 640         range 7 64 if PPC32 && PPC_64K_PAGES
 641         default "7" if PPC32 && PPC_64K_PAGES
 642         range 5 64 if PPC32 && PPC_256K_PAGES
 643         default "5" if PPC32 && PPC_256K_PAGES
 644         range 11 64
 645         default "11"
 646         help
 647           The kernel memory allocator divides physically contiguous memory
 648           blocks into "zones", where each zone is a power of two number of
 649           pages.  This option selects the largest power of two that the kernel
 650           keeps in the memory allocator.  If you need to allocate very large
 651           blocks of physically contiguous memory, then you may need to
 652           increase this value.
 653
 654           This config option is actually maximum order plus one. For example,
 655           a value of 11 means that the largest free memory block is 2^10 pages.
 656
 657           The page size is not necessarily 4KB.  For example, on 64-bit
 658           systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES.  Keep
 659           this in mind when choosing a value for this option.
 660
 661 config PPC_SUBPAGE_PROT
 662         bool "Support setting protections for 4k subpages"
 663         depends on PPC_STD_MMU_64 && PPC_64K_PAGES
 664         help
 665           This option adds support for a system call to allow user programs
 666           to set access permissions (read/write, readonly, or no access)
 667           on the 4k subpages of each 64k page.
 668
 669 config PPC_COPRO_BASE
 670         bool
 671         default n
 672
 673 config SCHED_SMT
 674         bool "SMT (Hyperthreading) scheduler support"
 675         depends on PPC64 && SMP
 676         help
 677           SMT scheduler support improves the CPU scheduler's decision making
 678           when dealing with POWER5 cpus at a cost of slightly increased
 679           overhead in some places. If unsure say N here.
 680
 681 config PPC_DENORMALISATION
 682         bool "PowerPC denormalisation exception handling"
 683         depends on PPC_BOOK3S_64
 684         default "y" if PPC_POWERNV
 685         ---help---
 686           Add support for handling denormalisation of single precision
 687           values.  Useful for bare metal only.  If unsure say Y here.
 688
 689 config CMDLINE_BOOL
 690         bool "Default bootloader kernel arguments"
 691
 692 config CMDLINE
 693         string "Initial kernel command string"
 694         depends on CMDLINE_BOOL
 695         default "console=ttyS0,9600 console=tty0 root=/dev/sda2"
 696         help
 697           On some platforms, there is currently no way for the boot loader to
 698           pass arguments to the kernel. For these platforms, you can supply
 699           some command-line options at build time by entering them here.  In
 700           most cases you will need to specify the root device here.
 701
 702 config CMDLINE_FORCE
 703         bool "Always use the default kernel command string"
 704         depends on CMDLINE_BOOL
 705         help
 706           Always use the default kernel command string, even if the boot
 707           loader passes other arguments to the kernel.
 708           This is useful if you cannot or don't want to change the
 709           command-line options your boot loader passes to the kernel.
 710
 711 config EXTRA_TARGETS
 712         string "Additional default image types"
 713         help
 714           List additional targets to be built by the bootwrapper here (separated
 715           by spaces).  This is useful for targets that depend of device tree
 716           files in the .dts directory.
 717
 718           Targets in this list will be build as part of the default build
 719           target, or when the user does a 'make zImage' or a
 720           'make zImage.initrd'.
 721
 722           If unsure, leave blank
 723
 724 config ARCH_WANTS_FREEZER_CONTROL
 725         def_bool y
 726         depends on ADB_PMU
 727
 728 source kernel/power/Kconfig
 729
 730 config SECCOMP
 731         bool "Enable seccomp to safely compute untrusted bytecode"
 732         depends on PROC_FS
 733         default y
 734         help
 735           This kernel feature is useful for number crunching applications
 736           that may need to compute untrusted bytecode during their
 737           execution. By using pipes or other transports made available to
 738           the process as file descriptors supporting the read/write
 739           syscalls, it's possible to isolate those applications in
 740           their own address space using seccomp. Once seccomp is
 741           enabled via /proc/<pid>/seccomp, it cannot be disabled
 742           and the task is only allowed to execute a few safe syscalls
 743           defined by each seccomp mode.
 744
 745           If unsure, say Y. Only embedded should say N here.
 746
 747 endmenu
 748
 749 config ISA_DMA_API
 750         bool
 751         default PCI
 752
 753 menu "Bus options"
 754
 755 config ISA
 756         bool "Support for ISA-bus hardware"
 757         depends on PPC_CHRP
 758         select PPC_I8259
 759         help
 760           Find out whether you have ISA slots on your motherboard.  ISA is the
 761           name of a bus system, i.e. the way the CPU talks to the other stuff
 762           inside your box.  If you have an Apple machine, say N here; if you
 763           have an IBM RS/6000 or pSeries machine, say Y.  If you have an
 764           embedded board, consult your board documentation.
 765
 766 config ZONE_DMA
 767         bool
 768         default y
 769
 770 config NEED_DMA_MAP_STATE
 771         def_bool (PPC64 || NOT_COHERENT_CACHE)
 772
 773 config NEED_SG_DMA_LENGTH
 774         def_bool y
 775
 776 config GENERIC_ISA_DMA
 777         bool
 778         depends on ISA_DMA_API
 779         default y
 780
 781 config PPC_INDIRECT_PCI
 782         bool
 783         depends on PCI
 784         default y if 40x || 44x
 785         default n
 786
 787 config EISA
 788         bool
 789
 790 config SBUS
 791         bool
 792
 793 config FSL_SOC
 794         bool
 795
 796 config FSL_PCI
 797         bool
 798         select PPC_INDIRECT_PCI
 799         select PCI_QUIRKS
 800
 801 config FSL_PMC
 802         bool
 803         default y
 804         depends on SUSPEND && (PPC_85xx || PPC_86xx)
 805         help
 806           Freescale MPC85xx/MPC86xx power management controller support
 807           (suspend/resume). For MPC83xx see platforms/83xx/suspend.c
 808
 809 config PPC4xx_CPM
 810         bool
 811         default y
 812         depends on SUSPEND && (44x || 40x)
 813         help
 814           PPC4xx Clock Power Management (CPM) support (suspend/resume).
 815           It also enables support for two different idle states (idle-wait
 816           and idle-doze).
 817
 818 config 4xx_SOC
 819         bool
 820
 821 config FSL_LBC
 822         bool "Freescale Local Bus support"
 823         help
 824           Enables reporting of errors from the Freescale local bus
 825           controller.  Also contains some common code used by
 826           drivers for specific local bus peripherals.
 827
 828 config FSL_GTM
 829         bool
 830         depends on PPC_83xx || QUICC_ENGINE || CPM2
 831         help
 832           Freescale General-purpose Timers support
 833
 834 # Yes MCA RS/6000s exist but Linux-PPC does not currently support any
 835 config MCA
 836         bool
 837
 838 # Platforms that what PCI turned unconditionally just do select PCI
 839 # in their config node.  Platforms that want to choose at config
 840 # time should select PPC_PCI_CHOICE
 841 config PPC_PCI_CHOICE
 842         bool
 843
 844 config PCI
 845         bool "PCI support" if PPC_PCI_CHOICE
 846         default y if !40x && !CPM2 && !8xx && !PPC_83xx \
 847                 && !PPC_85xx && !PPC_86xx && !GAMECUBE_COMMON
 848         default PCI_QSPAN if !4xx && !CPM2 && 8xx
 849         select GENERIC_PCI_IOMAP
 850         help
 851           Find out whether your system includes a PCI bus. PCI is the name of
 852           a bus system, i.e. the way the CPU talks to the other stuff inside
 853           your box.  If you say Y here, the kernel will include drivers and
 854           infrastructure code to support PCI bus devices.
 855
 856 config PCI_DOMAINS
 857         def_bool PCI
 858
 859 config PCI_SYSCALL
 860         def_bool PCI
 861
 862 config PCI_QSPAN
 863         bool "QSpan PCI"
 864         depends on !4xx && !CPM2 && 8xx
 865         select PPC_I8259
 866         help
 867           Say Y here if you have a system based on a Motorola 8xx-series
 868           embedded processor with a QSPAN PCI interface, otherwise say N.
 869
 870 config PCI_8260
 871         bool
 872         depends on PCI && 8260
 873         select PPC_INDIRECT_PCI
 874         default y
 875
 876 source "drivers/pci/Kconfig"
 877
 878 source "drivers/pcmcia/Kconfig"
 879
 880 config HAS_RAPIDIO
 881         bool
 882         default n
 883
 884 config RAPIDIO
 885         tristate "RapidIO support"
 886         depends on HAS_RAPIDIO || PCI
 887         help
 888           If you say Y here, the kernel will include drivers and
 889           infrastructure code to support RapidIO interconnect devices.
 890
 891 config FSL_RIO
 892         bool "Freescale Embedded SRIO Controller support"
 893         depends on RAPIDIO = y && HAS_RAPIDIO
 894         default "n"
 895         ---help---
 896           Include support for RapidIO controller on Freescale embedded
 897           processors (MPC8548, MPC8641, etc).
 898
 899 source "drivers/rapidio/Kconfig"
 900
 901 endmenu
 902
 903 config NONSTATIC_KERNEL
 904         bool
 905         default n
 906
 907 menu "Advanced setup"
 908         depends on PPC32
 909
 910 config ADVANCED_OPTIONS
 911         bool "Prompt for advanced kernel configuration options"
 912         help
 913           This option will enable prompting for a variety of advanced kernel
 914           configuration options.  These options can cause the kernel to not
 915           work if they are set incorrectly, but can be used to optimize certain
 916           aspects of kernel memory management.
 917
 918           Unless you know what you are doing, say N here.
 919
 920 comment "Default settings for advanced configuration options are used"
 921         depends on !ADVANCED_OPTIONS
 922
 923 config LOWMEM_SIZE_BOOL
 924         bool "Set maximum low memory"
 925         depends on ADVANCED_OPTIONS
 926         help
 927           This option allows you to set the maximum amount of memory which
 928           will be used as "low memory", that is, memory which the kernel can
 929           access directly, without having to set up a kernel virtual mapping.
 930           This can be useful in optimizing the layout of kernel virtual
 931           memory.
 932
 933           Say N here unless you know what you are doing.
 934
 935 config LOWMEM_SIZE
 936         hex "Maximum low memory size (in bytes)" if LOWMEM_SIZE_BOOL
 937         default "0x30000000"
 938
 939 config LOWMEM_CAM_NUM_BOOL
 940         bool "Set number of CAMs to use to map low memory"
 941         depends on ADVANCED_OPTIONS && FSL_BOOKE
 942         help
 943           This option allows you to set the maximum number of CAM slots that
 944           will be used to map low memory.  There are a limited number of slots
 945           available and even more limited number that will fit in the L1 MMU.
 946           However, using more entries will allow mapping more low memory.  This
 947           can be useful in optimizing the layout of kernel virtual memory.
 948
 949           Say N here unless you know what you are doing.
 950
 951 config LOWMEM_CAM_NUM
 952         depends on FSL_BOOKE
 953         int "Number of CAMs to use to map low memory" if LOWMEM_CAM_NUM_BOOL
 954         default 3
 955
 956 config DYNAMIC_MEMSTART
 957         bool "Enable page aligned dynamic load address for kernel"
 958         depends on ADVANCED_OPTIONS && FLATMEM && (FSL_BOOKE || 44x)
 959         select NONSTATIC_KERNEL
 960         help
 961           This option enables the kernel to be loaded at any page aligned
 962           physical address. The kernel creates a mapping from KERNELBASE to
 963           the address where the kernel is loaded. The page size here implies
 964           the TLB page size of the mapping for kernel on the particular platform.
 965           Please refer to the init code for finding the TLB page size.
 966
 967           DYNAMIC_MEMSTART is an easy way of implementing pseudo-RELOCATABLE
 968           kernel image, where the only restriction is the page aligned kernel
 969           load address. When this option is enabled, the compile time physical
 970           address CONFIG_PHYSICAL_START is ignored.
 971
 972           This option is overridden by CONFIG_RELOCATABLE
 973
 974 config PAGE_OFFSET_BOOL
 975         bool "Set custom page offset address"
 976         depends on ADVANCED_OPTIONS
 977         help
 978           This option allows you to set the kernel virtual address at which
 979           the kernel will map low memory.  This can be useful in optimizing
 980           the virtual memory layout of the system.
 981
 982           Say N here unless you know what you are doing.
 983
 984 config PAGE_OFFSET
 985         hex "Virtual address of memory base" if PAGE_OFFSET_BOOL
 986         default "0xc0000000"
 987
 988 config KERNEL_START_BOOL
 989         bool "Set custom kernel base address"
 990         depends on ADVANCED_OPTIONS
 991         help
 992           This option allows you to set the kernel virtual address at which
 993           the kernel will be loaded.  Normally this should match PAGE_OFFSET
 994           however there are times (like kdump) that one might not want them
 995           to be the same.
 996
 997           Say N here unless you know what you are doing.
 998
 999 config KERNEL_START
1000         hex "Virtual address of kernel base" if KERNEL_START_BOOL
1001         default PAGE_OFFSET if PAGE_OFFSET_BOOL
1002         default "0xc2000000" if CRASH_DUMP && !NONSTATIC_KERNEL
1003         default "0xc0000000"
1004
1005 config PHYSICAL_START_BOOL
1006         bool "Set physical address where the kernel is loaded"
1007         depends on ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
1008         help
1009           This gives the physical address where the kernel is loaded.
1010
1011           Say N here unless you know what you are doing.
1012
1013 config PHYSICAL_START
1014         hex "Physical address where the kernel is loaded" if PHYSICAL_START_BOOL
1015         default "0x02000000" if PPC_STD_MMU && CRASH_DUMP && !NONSTATIC_KERNEL
1016         default "0x00000000"
1017
1018 config PHYSICAL_ALIGN
1019         hex
1020         default "0x04000000" if FSL_BOOKE
1021         help
1022           This value puts the alignment restrictions on physical address
1023           where kernel is loaded and run from. Kernel is compiled for an
1024           address which meets above alignment restriction.
1025
1026 config TASK_SIZE_BOOL
1027         bool "Set custom user task size"
1028         depends on ADVANCED_OPTIONS
1029         help
1030           This option allows you to set the amount of virtual address space
1031           allocated to user tasks.  This can be useful in optimizing the
1032           virtual memory layout of the system.
1033
1034           Say N here unless you know what you are doing.
1035
1036 config TASK_SIZE
1037         hex "Size of user task space" if TASK_SIZE_BOOL
1038         default "0x80000000" if PPC_8xx
1039         default "0xc0000000"
1040
1041 config CONSISTENT_SIZE_BOOL
1042         bool "Set custom consistent memory pool size"
1043         depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE
1044         help
1045           This option allows you to set the size of the
1046           consistent memory pool.  This pool of virtual memory
1047           is used to make consistent memory allocations.
1048
1049 config CONSISTENT_SIZE
1050         hex "Size of consistent memory pool" if CONSISTENT_SIZE_BOOL
1051         default "0x00200000" if NOT_COHERENT_CACHE
1052
1053 config PIN_TLB
1054         bool "Pinned Kernel TLBs (860 ONLY)"
1055         depends on ADVANCED_OPTIONS && 8xx
1056
1057 config PIN_TLB_IMMR
1058         bool "Pinned TLB for IMMR"
1059         depends on PIN_TLB
1060         default y
1061 endmenu
1062
1063 if PPC64
1064 # This value must have zeroes in the bottom 60 bits otherwise lots will break
1065 config PAGE_OFFSET
1066         hex
1067         default "0xc000000000000000"
1068 config KERNEL_START
1069         hex
1070         default "0xc000000000000000"
1071 config PHYSICAL_START
1072         hex
1073         default "0x00000000"
1074 endif
1075
1076 config  ARCH_RANDOM
1077         def_bool n
1078
1079 source "net/Kconfig"
1080
1081 source "drivers/Kconfig"
1082
1083 source "fs/Kconfig"
1084
1085 source "lib/Kconfig"
1086
1087 source "arch/powerpc/Kconfig.debug"
1088
1089 source "security/Kconfig"
1090
1091 config KEYS_COMPAT
1092         bool
1093         depends on COMPAT && KEYS
1094         default y
1095
1096 source "crypto/Kconfig"
1097
1098 config PPC_LIB_RHEAP
1099         bool
1100
1101 source "arch/powerpc/kvm/Kconfig"
1102
1103 source "kernel/livepatch/Kconfig"