1 # SPDX-License-Identifier: GPL-2.0
2 source "arch/powerpc/platforms/Kconfig.cputype"
16 config ARCH_MMAP_RND_BITS_MAX
17 # On Book3S 64, the default virtual address space for 64-bit processes
18 # is 2^47 (128TB). As a maximum, allow randomisation to consume up to
19 # 32T of address space (2^45), which should ensure a reasonable gap
20 # between bottom-up and top-down allocations for applications that
21 # consume "normal" amounts of address space. Book3S 64 only supports 64K
23 default 29 if PPC_BOOK3S_64 && PPC_64K_PAGES # 29 = 45 (32T) - 16 (64K)
24 default 33 if PPC_BOOK3S_64 # 33 = 45 (32T) - 12 (4K)
26 # On all other 64-bit platforms (currently only Book3E), the virtual
27 # address space is 2^46 (64TB). Allow randomisation to consume up to 16T
28 # of address space (2^44). Only 4K page sizes are supported.
29 default 32 if 64BIT # 32 = 44 (16T) - 12 (4K)
31 # For 32-bit, use the compat values, as they're the same.
32 default ARCH_MMAP_RND_COMPAT_BITS_MAX
34 config ARCH_MMAP_RND_BITS_MIN
35 # Allow randomisation to consume up to 1GB of address space (2^30).
36 default 14 if 64BIT && PPC_64K_PAGES # 14 = 30 (1GB) - 16 (64K)
37 default 18 if 64BIT # 18 = 30 (1GB) - 12 (4K)
39 # For 32-bit, use the compat values, as they're the same.
40 default ARCH_MMAP_RND_COMPAT_BITS_MIN
42 config ARCH_MMAP_RND_COMPAT_BITS_MAX
43 # Total virtual address space for 32-bit processes is 2^31 (2GB).
44 # Allow randomisation to consume up to 512MB of address space (2^29).
45 default 11 if PPC_256K_PAGES # 11 = 29 (512MB) - 18 (256K)
46 default 13 if PPC_64K_PAGES # 13 = 29 (512MB) - 16 (64K)
47 default 15 if PPC_16K_PAGES # 15 = 29 (512MB) - 14 (16K)
48 default 17 # 17 = 29 (512MB) - 12 (4K)
50 config ARCH_MMAP_RND_COMPAT_BITS_MIN
51 # Total virtual address space for 32-bit processes is 2^31 (2GB).
52 # Allow randomisation to consume up to 8MB of address space (2^23).
53 default 5 if PPC_256K_PAGES # 5 = 23 (8MB) - 18 (256K)
54 default 7 if PPC_64K_PAGES # 7 = 23 (8MB) - 16 (64K)
55 default 9 if PPC_16K_PAGES # 9 = 23 (8MB) - 14 (16K)
56 default 11 # 11 = 23 (8MB) - 12 (4K)
58 config HAVE_SETUP_PER_CPU_AREA
61 config NEED_PER_CPU_EMBED_FIRST_CHUNK
65 int "Number of virtual interrupt numbers"
69 This defines the number of virtual interrupt numbers the kernel
70 can manage. Virtual interrupt numbers are what you see in
71 /proc/interrupts. If you configure your system to have too few,
72 drivers will fail to load or worse - handle with care.
76 depends on SMP && (DEBUGGER || KEXEC_CORE || HARDLOCKUP_DETECTOR)
81 depends on HARDLOCKUP_DETECTOR
82 depends on HAVE_HARDLOCKUP_DETECTOR_ARCH
85 This is a placeholder when the powerpc hardlockup detector
86 watchdog is selected (arch/powerpc/kernel/watchdog.c). It is
87 seleted via the generic lockup detector menu which is why we
88 have no standalone config option for it here.
90 config STACKTRACE_SUPPORT
94 config TRACE_IRQFLAGS_SUPPORT
98 config LOCKDEP_SUPPORT
102 config GENERIC_LOCKBREAK
105 depends on SMP && PREEMPTION
107 config GENERIC_HWEIGHT
115 # Please keep this list sorted alphabetically.
117 select ARCH_32BIT_OFF_T if PPC32
118 select ARCH_HAS_DEBUG_VIRTUAL
119 select ARCH_HAS_DEVMEM_IS_ALLOWED
120 select ARCH_HAS_ELF_RANDOMIZE
121 select ARCH_HAS_FORTIFY_SOURCE
122 select ARCH_HAS_GCOV_PROFILE_ALL
124 select ARCH_HAS_HUGEPD if HUGETLB_PAGE
125 select ARCH_HAS_MEMREMAP_COMPAT_ALIGN
126 select ARCH_HAS_MMIOWB if PPC64
127 select ARCH_HAS_PHYS_TO_DMA
128 select ARCH_HAS_PMEM_API
129 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
130 select ARCH_HAS_PTE_DEVMAP if PPC_BOOK3S_64
131 select ARCH_HAS_PTE_SPECIAL
132 select ARCH_HAS_MEMBARRIER_CALLBACKS
133 select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC_BOOK3S_64
134 select ARCH_HAS_STRICT_KERNEL_RWX if (PPC32 && !HIBERNATION)
135 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
136 select ARCH_HAS_UACCESS_FLUSHCACHE
137 select ARCH_HAS_UACCESS_MCSAFE if PPC64
138 select ARCH_HAS_UBSAN_SANITIZE_ALL
139 select ARCH_HAVE_NMI_SAFE_CMPXCHG
140 select ARCH_KEEP_MEMBLOCK
141 select ARCH_MIGHT_HAVE_PC_PARPORT
142 select ARCH_MIGHT_HAVE_PC_SERIO
143 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
144 select ARCH_SUPPORTS_ATOMIC_RMW
145 select ARCH_USE_BUILTIN_BSWAP
146 select ARCH_USE_CMPXCHG_LOCKREF if PPC64
147 select ARCH_WANT_IPC_PARSE_VERSION
148 select ARCH_WEAK_RELEASE_ACQUIRE
150 select BUILDTIME_TABLE_SORT
151 select CLONE_BACKWARDS
152 select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN
153 select DYNAMIC_FTRACE if FUNCTION_TRACER
154 select EDAC_ATOMIC_SCRUB
156 select GENERIC_ATOMIC64 if PPC32
157 select GENERIC_CLOCKEVENTS
158 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
159 select GENERIC_CMOS_UPDATE
160 select GENERIC_CPU_AUTOPROBE
161 select GENERIC_CPU_VULNERABILITIES if PPC_BARRIER_NOSPEC
162 select GENERIC_EARLY_IOREMAP
163 select GENERIC_IRQ_SHOW
164 select GENERIC_IRQ_SHOW_LEVEL
165 select GENERIC_PCI_IOMAP if PCI
166 select GENERIC_SMP_IDLE_THREAD
167 select GENERIC_STRNCPY_FROM_USER
168 select GENERIC_STRNLEN_USER
169 select GENERIC_TIME_VSYSCALL
170 select HAVE_ARCH_AUDITSYSCALL
171 select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU
172 select HAVE_ARCH_JUMP_LABEL
173 select HAVE_ARCH_KASAN if PPC32
174 select HAVE_ARCH_KASAN_VMALLOC if PPC32
175 select HAVE_ARCH_KGDB
176 select HAVE_ARCH_MMAP_RND_BITS
177 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
178 select HAVE_ARCH_NVRAM_OPS
179 select HAVE_ARCH_SECCOMP_FILTER
180 select HAVE_ARCH_TRACEHOOK
181 select HAVE_ASM_MODVERSIONS
182 select HAVE_C_RECORDMCOUNT
183 select HAVE_CBPF_JIT if !PPC64
184 select HAVE_STACKPROTECTOR if PPC64 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13)
185 select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r2)
186 select HAVE_CONTEXT_TRACKING if PPC64
187 select HAVE_TIF_NOHZ if PPC64
188 select HAVE_COPY_THREAD_TLS
189 select HAVE_DEBUG_KMEMLEAK
190 select HAVE_DEBUG_STACKOVERFLOW
191 select HAVE_DYNAMIC_FTRACE
192 select HAVE_DYNAMIC_FTRACE_WITH_REGS if MPROFILE_KERNEL
193 select HAVE_EBPF_JIT if PPC64
194 select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU)
196 select HAVE_FTRACE_MCOUNT_RECORD
197 select HAVE_FUNCTION_ERROR_INJECTION
198 select HAVE_FUNCTION_GRAPH_TRACER
199 select HAVE_FUNCTION_TRACER
200 select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC
201 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
203 select HAVE_IOREMAP_PROT
204 select HAVE_IRQ_EXIT_ON_IRQ_STACK
205 select HAVE_KERNEL_GZIP
206 select HAVE_KERNEL_LZMA if DEFAULT_UIMAGE
207 select HAVE_KERNEL_LZO if DEFAULT_UIMAGE
208 select HAVE_KERNEL_XZ if PPC_BOOK3S || 44x
210 select HAVE_KPROBES_ON_FTRACE
211 select HAVE_KRETPROBES
212 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
213 select HAVE_LIVEPATCH if HAVE_DYNAMIC_FTRACE_WITH_REGS
214 select HAVE_MEMBLOCK_NODE_MAP
215 select HAVE_MOD_ARCH_SPECIFIC
216 select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
217 select HAVE_HARDLOCKUP_DETECTOR_ARCH if (PPC64 && PPC_BOOK3S)
219 select HAVE_OPTPROBES if PPC64
220 select HAVE_PERF_EVENTS
221 select HAVE_PERF_EVENTS_NMI if PPC64
222 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
223 select HAVE_PERF_REGS
224 select HAVE_PERF_USER_STACK_DUMP
225 select MMU_GATHER_RCU_TABLE_FREE
226 select MMU_GATHER_PAGE_SIZE
227 select HAVE_REGS_AND_STACK_ACCESS_API
228 select HAVE_RELIABLE_STACKTRACE if PPC_BOOK3S_64 && CPU_LITTLE_ENDIAN
229 select HAVE_SYSCALL_TRACEPOINTS
230 select HAVE_VIRT_CPU_ACCOUNTING
231 select HAVE_IRQ_TIME_ACCOUNTING
233 select IOMMU_HELPER if PPC64
235 select IRQ_FORCED_THREADING
236 select MODULES_USE_ELF_RELA
237 select NEED_DMA_MAP_STATE if PPC64 || NOT_COHERENT_CACHE
238 select NEED_SG_DMA_LENGTH
240 select OF_DMA_DEFAULT_COHERENT if !NOT_COHERENT_CACHE
241 select OF_EARLY_FLATTREE
242 select OLD_SIGACTION if PPC32
243 select OLD_SIGSUSPEND
244 select PCI_DOMAINS if PCI
245 select PCI_SYSCALL if PCI
246 select PPC_DAWR if PPC64
249 select SYSCTL_EXCEPTION_TRACE
250 select THREAD_INFO_IN_TASK
251 select VIRT_TO_BUS if !PPC64
253 # Please keep this list sorted alphabetically.
256 config PPC_BARRIER_NOSPEC
259 depends on PPC_BOOK3S_64 || PPC_FSL_BOOK3E
270 bool "Enable support for 32bit binaries"
272 default y if !CPU_LITTLE_ENDIAN
273 select COMPAT_BINFMT_ELF
274 select ARCH_WANT_OLD_COMPAT_IPC
275 select COMPAT_OLD_SIGACTION
277 config SYSVIPC_COMPAT
279 depends on COMPAT && SYSVIPC
282 config SCHED_OMIT_FRAME_POINTER
286 config ARCH_MAY_HAVE_PC_FDC
290 config PPC_UDBG_16550
293 config GENERIC_TBSYNC
295 default y if PPC32 && SMP
306 config SYS_SUPPORTS_APM_EMULATION
307 default y if PMAC_APM_EMU
313 Used to allow a board to specify it wants an ePAPR compliant wrapper.
315 config DEFAULT_UIMAGE
318 Used to allow a board to specify it wants a uImage built by default
320 config ARCH_HIBERNATION_POSSIBLE
324 config ARCH_SUSPEND_POSSIBLE
326 depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx || \
327 (PPC_85xx && !PPC_E500MC) || PPC_86xx || PPC_PSERIES \
330 config ARCH_SUSPEND_NONZERO_CPU
332 depends on PPC_POWERNV || PPC_PSERIES
334 config PPC_DCR_NATIVE
342 depends on PPC_DCR_NATIVE || PPC_DCR_MMIO
345 config PPC_OF_PLATFORM_PCI
348 depends on PPC64 # not supported on 32 bits yet
350 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
351 depends on PPC32 || PPC_BOOK3S_64
354 config ARCH_SUPPORTS_UPROBES
357 config PPC_ADV_DEBUG_REGS
359 depends on 40x || BOOKE
362 config PPC_ADV_DEBUG_IACS
364 depends on PPC_ADV_DEBUG_REGS
368 config PPC_ADV_DEBUG_DACS
370 depends on PPC_ADV_DEBUG_REGS
373 config PPC_ADV_DEBUG_DVCS
375 depends on PPC_ADV_DEBUG_REGS
379 config PPC_ADV_DEBUG_DAC_RANGE
381 depends on PPC_ADV_DEBUG_REGS && 44x
389 default y if PPC_BOOK3E_64
391 config PGTABLE_LEVELS
396 source "arch/powerpc/sysdev/Kconfig"
397 source "arch/powerpc/platforms/Kconfig"
399 menu "Kernel options"
402 bool "High memory support"
405 source "kernel/Kconfig.hz"
407 config HUGETLB_PAGE_SIZE_VARIABLE
409 depends on HUGETLB_PAGE && PPC_BOOK3S_64
412 config MATH_EMULATION
413 bool "Math emulation"
414 depends on 4xx || PPC_8xx || PPC_MPC832x || BOOKE
416 Some PowerPC chips designed for embedded applications do not have
417 a floating-point unit and therefore do not implement the
418 floating-point instructions in the PowerPC instruction set. If you
419 say Y here, the kernel will include code to emulate a floating-point
420 unit, which will allow programs that use floating-point
423 This is also useful to emulate missing (optional) instructions
424 such as fsqrt on cores that do have an FPU but do not implement
425 them (such as Freescale BookE).
428 prompt "Math emulation options"
429 default MATH_EMULATION_FULL
430 depends on MATH_EMULATION
432 config MATH_EMULATION_FULL
433 bool "Emulate all the floating point instructions"
435 Select this option will enable the kernel to support to emulate
436 all the floating point instructions. If your SoC doesn't have
437 a FPU, you should select this.
439 config MATH_EMULATION_HW_UNIMPLEMENTED
440 bool "Just emulate the FPU unimplemented instructions"
442 Select this if you know there does have a hardware FPU on your
443 SoC, but some floating point instructions are not implemented by that.
447 config PPC_TRANSACTIONAL_MEM
448 bool "Transactional Memory support for POWERPC"
449 depends on PPC_BOOK3S_64
454 Support user-mode Transactional Memory on POWERPC.
457 bool "Ultravisor support"
458 depends on KVM_BOOK3S_HV_POSSIBLE
459 depends on DEVICE_PRIVATE
462 This option paravirtualizes the kernel to run in POWER platforms that
463 supports the Protected Execution Facility (PEF). On such platforms,
464 the ultravisor firmware runs at a privilege level above the
469 config LD_HEAD_STUB_CATCH
470 bool "Reserve 256 bytes to cope with linker stubs in HEAD text" if EXPERT
473 Very large kernels can cause linker branch stubs to be generated by
474 code in head_64.S, which moves the head text sections out of their
475 specified location. This option can work around the problem.
479 config MPROFILE_KERNEL
480 depends on PPC64 && CPU_LITTLE_ENDIAN
481 def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__)
484 bool "Support for enabling/disabling CPUs"
485 depends on SMP && (PPC_PSERIES || \
486 PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE)
488 Say Y here to be able to disable and re-enable individual
489 CPUs at runtime on SMP machines.
491 Say N if you are unsure.
493 config ARCH_CPU_PROBE_RELEASE
495 depends on HOTPLUG_CPU
497 config ARCH_ENABLE_MEMORY_HOTPLUG
500 config ARCH_ENABLE_MEMORY_HOTREMOVE
503 config PPC64_SUPPORTS_MEMORY_FAILURE
504 bool "Add support for memory hwpoison"
505 depends on PPC_BOOK3S_64
506 default "y" if PPC_POWERNV
507 select ARCH_SUPPORTS_MEMORY_FAILURE
510 bool "kexec system call"
511 depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP)) || PPC_BOOK3E
514 kexec is a system call that implements the ability to shutdown your
515 current kernel, and to start another kernel. It is like a reboot
516 but it is independent of the system firmware. And like a reboot
517 you can start any kernel with it, not just Linux.
519 The name comes from the similarity to the exec system call.
521 It is an ongoing process to be certain the hardware in a machine
522 is properly shutdown, so do not be surprised if this code does not
523 initially work for you. As of this writing the exact hardware
524 interface is strongly in flux, so no good recommendation can be
528 bool "kexec file based system call"
530 select HAVE_IMA_KEXEC
535 depends on CRYPTO_SHA256=y
537 This is a new version of the kexec system call. This call is
538 file based and takes in file descriptors as system call arguments
539 for kernel and initramfs as opposed to a list of segments as is the
540 case for the older kexec call.
542 config ARCH_HAS_KEXEC_PURGATORY
546 bool "Build a relocatable kernel"
547 depends on PPC64 || (FLATMEM && (44x || FSL_BOOKE))
548 select NONSTATIC_KERNEL
549 select MODULE_REL_CRCS if MODVERSIONS
551 This builds a kernel image that is capable of running at the
552 location the kernel is loaded at. For ppc32, there is no any
553 alignment restrictions, and this feature is a superset of
554 DYNAMIC_MEMSTART and hence overrides it. For ppc64, we should use
555 16k-aligned base address. The kernel is linked as a
556 position-independent executable (PIE) and contains dynamic relocations
557 which are processed early in the bootup process.
559 One use is for the kexec on panic case where the recovery kernel
560 must live at a different physical address than the primary
563 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
564 it has been loaded at and the compile time physical addresses
565 CONFIG_PHYSICAL_START is ignored. However CONFIG_PHYSICAL_START
566 setting can still be useful to bootwrappers that need to know the
567 load address of the kernel (eg. u-boot/mkimage).
569 config RANDOMIZE_BASE
570 bool "Randomize the address of the kernel image"
571 depends on (FSL_BOOKE && FLATMEM && PPC32)
572 depends on RELOCATABLE
574 Randomizes the virtual address at which the kernel image is
575 loaded, as a security feature that deters exploit attempts
576 relying on knowledge of the location of kernel internals.
580 config RELOCATABLE_TEST
581 bool "Test relocatable kernel"
582 depends on (PPC64 && RELOCATABLE)
584 This runs the relocatable kernel at the address it was initially
585 loaded at, which tends to be non-zero and therefore test the
589 bool "Build a dump capture kernel"
590 depends on PPC64 || PPC_BOOK3S_32 || FSL_BOOKE || (44x && !SMP)
591 select RELOCATABLE if PPC64 || 44x || FSL_BOOKE
593 Build a kernel suitable for use as a dump capture kernel.
594 The same kernel binary can be used as production kernel and dump
598 bool "Firmware-assisted dump"
599 depends on PPC64 && (PPC_RTAS || PPC_POWERNV)
603 A robust mechanism to get reliable kernel crash dump with
604 assistance from firmware. This approach does not use kexec,
605 instead firmware assists in booting the capture kernel
606 while preserving memory contents. Firmware-assisted dump
607 is meant to be a kdump replacement offering robustness and
608 speed not possible without system firmware assistance.
610 If unsure, say "y". Only special kernels like petitboot may
611 need to say "N" here.
613 config PRESERVE_FA_DUMP
614 bool "Preserve Firmware-assisted dump"
615 depends on PPC64 && PPC_POWERNV && !FA_DUMP
617 On a kernel with FA_DUMP disabled, this option helps to preserve
618 crash data from a previously crash'ed kernel. Useful when the next
619 memory preserving kernel boot would process this crash data.
620 Petitboot kernel is the typical usecase for this option.
623 bool "Export OPAL memory as /sys/firmware/opal/core"
624 depends on PPC64 && PPC_POWERNV
626 This option uses the MPIPL support in firmware to provide an
627 ELF core of OPAL memory after a crash. The ELF core is exported
628 as /sys/firmware/opal/core file which is helpful in debugging
629 OPAL crashes using GDB.
632 bool "Distribute interrupts on all CPUs by default"
635 This option gives the kernel permission to distribute IRQs across
636 multiple CPUs. Saying N here will route all IRQs to the first
637 CPU. Generally saying Y is safe, although some problems have been
638 reported with SMP Power Macintoshes with this option enabled.
643 default y if SMP && PPC_PSERIES
649 depends on NEED_MULTIPLE_NODES
651 config USE_PERCPU_NUMA_NODE_ID
655 config HAVE_MEMORYLESS_NODES
659 config ARCH_SELECT_MEMORY_MODEL
663 config ARCH_FLATMEM_ENABLE
665 depends on (PPC64 && !NUMA) || PPC32
667 config ARCH_SPARSEMEM_ENABLE
670 select SPARSEMEM_VMEMMAP_ENABLE
672 config ARCH_SPARSEMEM_DEFAULT
674 depends on PPC_BOOK3S_64
676 config SYS_SUPPORTS_HUGETLBFS
679 config ILLEGAL_POINTER_VALUE
681 # This is roughly half way between the top of user space and the bottom
682 # of kernel space, which seems about as good as we can get.
683 default 0x5deadbeef0000000 if PPC64
686 config ARCH_MEMORY_PROBE
688 depends on MEMORY_HOTPLUG
690 # Some NUMA nodes have memory ranges that span
691 # other nodes. Even though a pfn is valid and
692 # between a node's start and end pfns, it may not
693 # reside on that node. See memmap_init_zone()
695 config NODES_SPAN_OTHER_NODES
697 depends on NEED_MULTIPLE_NODES
700 bool "Using standard binutils settings"
704 Turning this option off allows you to select 256KB PAGE_SIZE on 44x.
705 Note, that kernel will be able to run only those applications,
706 which had been compiled using binutils later than 2.17.50.0.3 with
707 '-zmax-page-size' set to 256K (the default is 64K). Or, if using
708 the older binutils, you can patch them with a trivial patch, which
709 changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000.
715 Select the kernel logical page size. Increasing the page size
716 will reduce software overhead at each page boundary, allow
717 hardware prefetch mechanisms to be more effective, and allow
718 larger dma transfers increasing IO efficiency and reducing
719 overhead. However the utilization of memory will increase.
720 For example, each cached file will using a multiple of the
721 page size to hold its contents and the difference between the
722 end of file and the end of page is wasted.
724 Some dedicated systems, such as software raid serving with
725 accelerated calculations, have shown significant increases.
727 If you configure a 64 bit kernel for 64k pages but the
728 processor does not support them, then the kernel will simulate
729 them with 4k pages, loading them on demand, but with the
730 reduced software overhead and larger internal fragmentation.
731 For the 32 bit kernel, a large page option will not be offered
732 unless it is supported by the configured processor.
734 If unsure, choose 4K_PAGES.
738 select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
742 depends on 44x || PPC_8xx
746 depends on 44x || PPC_BOOK3S_64
747 select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
749 config PPC_256K_PAGES
750 bool "256k page size"
751 depends on 44x && !STDBINUTILS
753 Make the page size 256k.
755 As the ELF standard only requires alignment to support page
756 sizes up to 64k, you will need to compile all of your user
757 space applications with a non-standard binutils settings
758 (see the STDBINUTILS description for details).
760 Say N unless you know what you are doing.
764 config PPC_PAGE_SHIFT
766 default 18 if PPC_256K_PAGES
767 default 16 if PPC_64K_PAGES
768 default 14 if PPC_16K_PAGES
772 int "Thread shift" if EXPERT
774 default "15" if PPC_256K_PAGES
775 default "14" if PPC64
778 Used to define the stack size. The default is almost always what you
779 want. Only change this if you know what you are doing.
781 config ETEXT_SHIFT_BOOL
782 bool "Set custom etext alignment" if STRICT_KERNEL_RWX && \
783 (PPC_BOOK3S_32 || PPC_8xx)
784 depends on ADVANCED_OPTIONS
786 This option allows you to set the kernel end of text alignment. When
787 RAM is mapped by blocks, the alignment needs to fit the size and
788 number of possible blocks. The default should be OK for most configs.
790 Say N here unless you know what you are doing.
793 int "_etext shift" if ETEXT_SHIFT_BOOL
794 range 17 28 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
795 range 19 23 if STRICT_KERNEL_RWX && PPC_8xx
796 default 17 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
797 default 19 if STRICT_KERNEL_RWX && PPC_8xx
798 default PPC_PAGE_SHIFT
800 On Book3S 32 (603+), IBATs are used to map kernel text.
801 Smaller is the alignment, greater is the number of necessary IBATs.
803 On 8xx, large pages (512kb or 8M) are used to map kernel linear
804 memory. Aligning to 8M reduces TLB misses as only 8M pages are used
807 config DATA_SHIFT_BOOL
808 bool "Set custom data alignment" if STRICT_KERNEL_RWX && \
809 (PPC_BOOK3S_32 || PPC_8xx)
810 depends on ADVANCED_OPTIONS
812 This option allows you to set the kernel data alignment. When
813 RAM is mapped by blocks, the alignment needs to fit the size and
814 number of possible blocks. The default should be OK for most configs.
816 Say N here unless you know what you are doing.
819 int "Data shift" if DATA_SHIFT_BOOL
820 default 24 if STRICT_KERNEL_RWX && PPC64
821 range 17 28 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
822 range 19 23 if STRICT_KERNEL_RWX && PPC_8xx
823 default 22 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
824 default 23 if STRICT_KERNEL_RWX && PPC_8xx
825 default PPC_PAGE_SHIFT
827 On Book3S 32 (603+), DBATs are used to map kernel text and rodata RO.
828 Smaller is the alignment, greater is the number of necessary DBATs.
830 On 8xx, large pages (512kb or 8M) are used to map kernel linear
831 memory. Aligning to 8M reduces TLB misses as only 8M pages are used
834 config FORCE_MAX_ZONEORDER
835 int "Maximum zone order"
836 range 8 9 if PPC64 && PPC_64K_PAGES
837 default "9" if PPC64 && PPC_64K_PAGES
838 range 13 13 if PPC64 && !PPC_64K_PAGES
839 default "13" if PPC64 && !PPC_64K_PAGES
840 range 9 64 if PPC32 && PPC_16K_PAGES
841 default "9" if PPC32 && PPC_16K_PAGES
842 range 7 64 if PPC32 && PPC_64K_PAGES
843 default "7" if PPC32 && PPC_64K_PAGES
844 range 5 64 if PPC32 && PPC_256K_PAGES
845 default "5" if PPC32 && PPC_256K_PAGES
849 The kernel memory allocator divides physically contiguous memory
850 blocks into "zones", where each zone is a power of two number of
851 pages. This option selects the largest power of two that the kernel
852 keeps in the memory allocator. If you need to allocate very large
853 blocks of physically contiguous memory, then you may need to
856 This config option is actually maximum order plus one. For example,
857 a value of 11 means that the largest free memory block is 2^10 pages.
859 The page size is not necessarily 4KB. For example, on 64-bit
860 systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep
861 this in mind when choosing a value for this option.
863 config PPC_SUBPAGE_PROT
864 bool "Support setting protections for 4k subpages"
865 depends on PPC_BOOK3S_64 && PPC_64K_PAGES
867 This option adds support for a system call to allow user programs
868 to set access permissions (read/write, readonly, or no access)
869 on the 4k subpages of each 64k page.
871 config PPC_COPRO_BASE
875 bool "SMT (Hyperthreading) scheduler support"
876 depends on PPC64 && SMP
878 SMT scheduler support improves the CPU scheduler's decision making
879 when dealing with POWER5 cpus at a cost of slightly increased
880 overhead in some places. If unsure say N here.
882 config PPC_DENORMALISATION
883 bool "PowerPC denormalisation exception handling"
884 depends on PPC_BOOK3S_64
885 default "y" if PPC_POWERNV
887 Add support for handling denormalisation of single precision
888 values. Useful for bare metal only. If unsure say Y here.
891 bool "Default bootloader kernel arguments"
894 string "Initial kernel command string" if CMDLINE_BOOL
895 default "console=ttyS0,9600 console=tty0 root=/dev/sda2" if CMDLINE_BOOL
898 On some platforms, there is currently no way for the boot loader to
899 pass arguments to the kernel. For these platforms, you can supply
900 some command-line options at build time by entering them here. In
901 most cases you will need to specify the root device here.
904 prompt "Kernel command line type" if CMDLINE != ""
905 default CMDLINE_FROM_BOOTLOADER
907 config CMDLINE_FROM_BOOTLOADER
908 bool "Use bootloader kernel arguments if available"
910 Uses the command-line options passed by the boot loader. If
911 the boot loader doesn't provide any, the default kernel command
912 string provided in CMDLINE will be used.
914 config CMDLINE_EXTEND
915 bool "Extend bootloader kernel arguments"
917 The command-line arguments provided by the boot loader will be
918 appended to the default kernel command string.
921 bool "Always use the default kernel command string"
923 Always use the default kernel command string, even if the boot
924 loader passes other arguments to the kernel.
925 This is useful if you cannot or don't want to change the
926 command-line options your boot loader passes to the kernel.
931 string "Additional default image types"
933 List additional targets to be built by the bootwrapper here (separated
934 by spaces). This is useful for targets that depend of device tree
935 files in the .dts directory.
937 Targets in this list will be build as part of the default build
938 target, or when the user does a 'make zImage' or a
939 'make zImage.initrd'.
941 If unsure, leave blank
943 config ARCH_WANTS_FREEZER_CONTROL
947 source "kernel/power/Kconfig"
950 bool "Enable seccomp to safely compute untrusted bytecode"
954 This kernel feature is useful for number crunching applications
955 that may need to compute untrusted bytecode during their
956 execution. By using pipes or other transports made available to
957 the process as file descriptors supporting the read/write
958 syscalls, it's possible to isolate those applications in
959 their own address space using seccomp. Once seccomp is
960 enabled via /proc/<pid>/seccomp, it cannot be disabled
961 and the task is only allowed to execute a few safe syscalls
962 defined by each seccomp mode.
964 If unsure, say Y. Only embedded should say N here.
967 prompt "PowerPC Memory Protection Keys"
969 depends on PPC_BOOK3S_64
970 select ARCH_USES_HIGH_VMA_FLAGS
971 select ARCH_HAS_PKEYS
973 Memory Protection Keys provides a mechanism for enforcing
974 page-based protections, but without requiring modification of the
975 page tables when an application changes protection domains.
977 For details, see Documentation/core-api/protection-keys.rst
981 config PPC_SECURE_BOOT
982 prompt "Enable secure boot support"
984 depends on PPC_POWERNV
985 depends on IMA_ARCH_POLICY
986 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
988 Systems with firmware secure boot enabled need to define security
989 policies to extend secure boot to the OS. This config allows a user
990 to enable OS secure boot on systems that have firmware support for
991 it. If in doubt say N.
993 config PPC_SECVAR_SYSFS
994 bool "Enable sysfs interface for POWER secure variables"
996 depends on PPC_SECURE_BOOT
999 POWER secure variables are managed and controlled by firmware.
1000 These variables are exposed to userspace via sysfs to enable
1001 read/write operations on these variables. Say Y if you have
1002 secure boot enabled and want to expose variables to userspace.
1013 bool "Support for ISA-bus hardware"
1017 Find out whether you have ISA slots on your motherboard. ISA is the
1018 name of a bus system, i.e. the way the CPU talks to the other stuff
1019 inside your box. If you have an Apple machine, say N here; if you
1020 have an IBM RS/6000 or pSeries machine, say Y. If you have an
1021 embedded board, consult your board documentation.
1023 config GENERIC_ISA_DMA
1025 depends on ISA_DMA_API
1028 config PPC_INDIRECT_PCI
1031 default y if 40x || 44x
1041 select ARCH_HAS_DMA_SET_MASK
1042 select PPC_INDIRECT_PCI
1048 depends on SUSPEND && (PPC_85xx || PPC_86xx)
1050 Freescale MPC85xx/MPC86xx power management controller support
1051 (suspend/resume). For MPC83xx see platforms/83xx/suspend.c
1056 depends on SUSPEND && (44x || 40x)
1058 PPC4xx Clock Power Management (CPM) support (suspend/resume).
1059 It also enables support for two different idle states (idle-wait
1066 bool "Freescale Local Bus support"
1068 Enables reporting of errors from the Freescale local bus
1069 controller. Also contains some common code used by
1070 drivers for specific local bus peripherals.
1074 depends on PPC_83xx || QUICC_ENGINE || CPM2
1076 Freescale General-purpose Timers support
1080 depends on PCI && 8260
1081 select PPC_INDIRECT_PCI
1085 bool "Freescale Embedded SRIO Controller support"
1086 depends on RAPIDIO = y && HAVE_RAPIDIO
1089 Include support for RapidIO controller on Freescale embedded
1090 processors (MPC8548, MPC8641, etc).
1094 config NONSTATIC_KERNEL
1097 menu "Advanced setup"
1100 config ADVANCED_OPTIONS
1101 bool "Prompt for advanced kernel configuration options"
1103 This option will enable prompting for a variety of advanced kernel
1104 configuration options. These options can cause the kernel to not
1105 work if they are set incorrectly, but can be used to optimize certain
1106 aspects of kernel memory management.
1108 Unless you know what you are doing, say N here.
1110 comment "Default settings for advanced configuration options are used"
1111 depends on !ADVANCED_OPTIONS
1113 config LOWMEM_SIZE_BOOL
1114 bool "Set maximum low memory"
1115 depends on ADVANCED_OPTIONS
1117 This option allows you to set the maximum amount of memory which
1118 will be used as "low memory", that is, memory which the kernel can
1119 access directly, without having to set up a kernel virtual mapping.
1120 This can be useful in optimizing the layout of kernel virtual
1123 Say N here unless you know what you are doing.
1126 hex "Maximum low memory size (in bytes)" if LOWMEM_SIZE_BOOL
1127 default "0x30000000"
1129 config LOWMEM_CAM_NUM_BOOL
1130 bool "Set number of CAMs to use to map low memory"
1131 depends on ADVANCED_OPTIONS && FSL_BOOKE
1133 This option allows you to set the maximum number of CAM slots that
1134 will be used to map low memory. There are a limited number of slots
1135 available and even more limited number that will fit in the L1 MMU.
1136 However, using more entries will allow mapping more low memory. This
1137 can be useful in optimizing the layout of kernel virtual memory.
1139 Say N here unless you know what you are doing.
1141 config LOWMEM_CAM_NUM
1142 depends on FSL_BOOKE
1143 int "Number of CAMs to use to map low memory" if LOWMEM_CAM_NUM_BOOL
1146 config DYNAMIC_MEMSTART
1147 bool "Enable page aligned dynamic load address for kernel"
1148 depends on ADVANCED_OPTIONS && FLATMEM && (FSL_BOOKE || 44x)
1149 select NONSTATIC_KERNEL
1151 This option enables the kernel to be loaded at any page aligned
1152 physical address. The kernel creates a mapping from KERNELBASE to
1153 the address where the kernel is loaded. The page size here implies
1154 the TLB page size of the mapping for kernel on the particular platform.
1155 Please refer to the init code for finding the TLB page size.
1157 DYNAMIC_MEMSTART is an easy way of implementing pseudo-RELOCATABLE
1158 kernel image, where the only restriction is the page aligned kernel
1159 load address. When this option is enabled, the compile time physical
1160 address CONFIG_PHYSICAL_START is ignored.
1162 This option is overridden by CONFIG_RELOCATABLE
1164 config PAGE_OFFSET_BOOL
1165 bool "Set custom page offset address"
1166 depends on ADVANCED_OPTIONS
1168 This option allows you to set the kernel virtual address at which
1169 the kernel will map low memory. This can be useful in optimizing
1170 the virtual memory layout of the system.
1172 Say N here unless you know what you are doing.
1175 hex "Virtual address of memory base" if PAGE_OFFSET_BOOL
1176 default "0xc0000000"
1178 config KERNEL_START_BOOL
1179 bool "Set custom kernel base address"
1180 depends on ADVANCED_OPTIONS
1182 This option allows you to set the kernel virtual address at which
1183 the kernel will be loaded. Normally this should match PAGE_OFFSET
1184 however there are times (like kdump) that one might not want them
1187 Say N here unless you know what you are doing.
1190 hex "Virtual address of kernel base" if KERNEL_START_BOOL
1191 default PAGE_OFFSET if PAGE_OFFSET_BOOL
1192 default "0xc2000000" if CRASH_DUMP && !NONSTATIC_KERNEL
1193 default "0xc0000000"
1195 config PHYSICAL_START_BOOL
1196 bool "Set physical address where the kernel is loaded"
1197 depends on ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
1199 This gives the physical address where the kernel is loaded.
1201 Say N here unless you know what you are doing.
1203 config PHYSICAL_START
1204 hex "Physical address where the kernel is loaded" if PHYSICAL_START_BOOL
1205 default "0x02000000" if PPC_BOOK3S && CRASH_DUMP && !NONSTATIC_KERNEL
1206 default "0x00000000"
1208 config PHYSICAL_ALIGN
1210 default "0x04000000" if FSL_BOOKE
1212 This value puts the alignment restrictions on physical address
1213 where kernel is loaded and run from. Kernel is compiled for an
1214 address which meets above alignment restriction.
1216 config TASK_SIZE_BOOL
1217 bool "Set custom user task size"
1218 depends on ADVANCED_OPTIONS
1220 This option allows you to set the amount of virtual address space
1221 allocated to user tasks. This can be useful in optimizing the
1222 virtual memory layout of the system.
1224 Say N here unless you know what you are doing.
1227 hex "Size of user task space" if TASK_SIZE_BOOL
1228 default "0x80000000" if PPC_8xx
1229 default "0xc0000000"
1232 bool "Pinned Kernel TLBs (860 ONLY)"
1233 depends on ADVANCED_OPTIONS && PPC_8xx && \
1234 !DEBUG_PAGEALLOC && !STRICT_KERNEL_RWX
1237 bool "Pinned TLB for DATA"
1242 bool "Pinned TLB for IMMR"
1243 depends on PIN_TLB || PPC_EARLY_DEBUG_CPM
1247 bool "Pinned TLB for TEXT"
1253 # This value must have zeroes in the bottom 60 bits otherwise lots will break
1256 default "0xc000000000000000"
1259 default "0xc000000000000000"
1260 config PHYSICAL_START
1262 default "0x00000000"
1268 config PPC_LIB_RHEAP
1271 source "arch/powerpc/kvm/Kconfig"
1273 source "kernel/livepatch/Kconfig"