1 # SPDX-License-Identifier: GPL-2.0
2 source "arch/powerpc/platforms/Kconfig.cputype"
20 config ARCH_MMAP_RND_BITS_MAX
21 # On Book3S 64, the default virtual address space for 64-bit processes
22 # is 2^47 (128TB). As a maximum, allow randomisation to consume up to
23 # 32T of address space (2^45), which should ensure a reasonable gap
24 # between bottom-up and top-down allocations for applications that
25 # consume "normal" amounts of address space. Book3S 64 only supports 64K
27 default 29 if PPC_BOOK3S_64 && PPC_64K_PAGES # 29 = 45 (32T) - 16 (64K)
28 default 33 if PPC_BOOK3S_64 # 33 = 45 (32T) - 12 (4K)
30 # On all other 64-bit platforms (currently only Book3E), the virtual
31 # address space is 2^46 (64TB). Allow randomisation to consume up to 16T
32 # of address space (2^44). Only 4K page sizes are supported.
33 default 32 if 64BIT # 32 = 44 (16T) - 12 (4K)
35 # For 32-bit, use the compat values, as they're the same.
36 default ARCH_MMAP_RND_COMPAT_BITS_MAX
38 config ARCH_MMAP_RND_BITS_MIN
39 # Allow randomisation to consume up to 1GB of address space (2^30).
40 default 14 if 64BIT && PPC_64K_PAGES # 14 = 30 (1GB) - 16 (64K)
41 default 18 if 64BIT # 18 = 30 (1GB) - 12 (4K)
43 # For 32-bit, use the compat values, as they're the same.
44 default ARCH_MMAP_RND_COMPAT_BITS_MIN
46 config ARCH_MMAP_RND_COMPAT_BITS_MAX
47 # Total virtual address space for 32-bit processes is 2^31 (2GB).
48 # Allow randomisation to consume up to 512MB of address space (2^29).
49 default 11 if PPC_256K_PAGES # 11 = 29 (512MB) - 18 (256K)
50 default 13 if PPC_64K_PAGES # 13 = 29 (512MB) - 16 (64K)
51 default 15 if PPC_16K_PAGES # 15 = 29 (512MB) - 14 (16K)
52 default 17 # 17 = 29 (512MB) - 12 (4K)
54 config ARCH_MMAP_RND_COMPAT_BITS_MIN
55 # Total virtual address space for 32-bit processes is 2^31 (2GB).
56 # Allow randomisation to consume up to 8MB of address space (2^23).
57 default 5 if PPC_256K_PAGES # 5 = 23 (8MB) - 18 (256K)
58 default 7 if PPC_64K_PAGES # 7 = 23 (8MB) - 16 (64K)
59 default 9 if PPC_16K_PAGES # 9 = 23 (8MB) - 14 (16K)
60 default 11 # 11 = 23 (8MB) - 12 (4K)
62 config HAVE_SETUP_PER_CPU_AREA
65 config NEED_PER_CPU_EMBED_FIRST_CHUNK
69 int "Number of virtual interrupt numbers"
73 This defines the number of virtual interrupt numbers the kernel
74 can manage. Virtual interrupt numbers are what you see in
75 /proc/interrupts. If you configure your system to have too few,
76 drivers will fail to load or worse - handle with care.
80 depends on SMP && (DEBUGGER || KEXEC_CORE || HARDLOCKUP_DETECTOR)
85 depends on HARDLOCKUP_DETECTOR
86 depends on HAVE_HARDLOCKUP_DETECTOR_ARCH
89 This is a placeholder when the powerpc hardlockup detector
90 watchdog is selected (arch/powerpc/kernel/watchdog.c). It is
91 seleted via the generic lockup detector menu which is why we
92 have no standalone config option for it here.
94 config STACKTRACE_SUPPORT
98 config TRACE_IRQFLAGS_SUPPORT
102 config LOCKDEP_SUPPORT
106 config GENERIC_LOCKBREAK
109 depends on SMP && PREEMPT
111 config GENERIC_HWEIGHT
119 # Please keep this list sorted alphabetically.
121 select ARCH_32BIT_OFF_T if PPC32
122 select ARCH_HAS_DEBUG_VIRTUAL
123 select ARCH_HAS_DEVMEM_IS_ALLOWED
124 select ARCH_HAS_ELF_RANDOMIZE
125 select ARCH_HAS_FORTIFY_SOURCE
126 select ARCH_HAS_GCOV_PROFILE_ALL
128 select ARCH_HAS_PHYS_TO_DMA
129 select ARCH_HAS_PMEM_API if PPC64
130 select ARCH_HAS_PTE_SPECIAL
131 select ARCH_HAS_MEMBARRIER_CALLBACKS
132 select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE && PPC64
133 select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !RELOCATABLE && !HIBERNATION)
134 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
135 select ARCH_HAS_UACCESS_FLUSHCACHE if PPC64
136 select ARCH_HAS_UBSAN_SANITIZE_ALL
137 select ARCH_HAS_ZONE_DEVICE if PPC_BOOK3S_64
138 select ARCH_HAVE_NMI_SAFE_CMPXCHG
139 select ARCH_MIGHT_HAVE_PC_PARPORT
140 select ARCH_MIGHT_HAVE_PC_SERIO
141 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
142 select ARCH_SUPPORTS_ATOMIC_RMW
143 select ARCH_USE_BUILTIN_BSWAP
144 select ARCH_USE_CMPXCHG_LOCKREF if PPC64
145 select ARCH_WANT_IPC_PARSE_VERSION
146 select ARCH_WEAK_RELEASE_ACQUIRE
148 select BUILDTIME_EXTABLE_SORT
149 select CLONE_BACKWARDS
150 select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN
151 select DYNAMIC_FTRACE if FUNCTION_TRACER
152 select EDAC_ATOMIC_SCRUB
154 select GENERIC_ATOMIC64 if PPC32
155 select GENERIC_CLOCKEVENTS
156 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
157 select GENERIC_CMOS_UPDATE
158 select GENERIC_CPU_AUTOPROBE
159 select GENERIC_CPU_VULNERABILITIES if PPC_BARRIER_NOSPEC
160 select GENERIC_IRQ_SHOW
161 select GENERIC_IRQ_SHOW_LEVEL
162 select GENERIC_PCI_IOMAP if PCI
163 select GENERIC_SMP_IDLE_THREAD
164 select GENERIC_STRNCPY_FROM_USER
165 select GENERIC_STRNLEN_USER
166 select GENERIC_TIME_VSYSCALL
167 select HAVE_ARCH_AUDITSYSCALL
168 select HAVE_ARCH_JUMP_LABEL
169 select HAVE_ARCH_KGDB
170 select HAVE_ARCH_MMAP_RND_BITS
171 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
172 select HAVE_ARCH_NVRAM_OPS
173 select HAVE_ARCH_SECCOMP_FILTER
174 select HAVE_ARCH_TRACEHOOK
175 select HAVE_CBPF_JIT if !PPC64
176 select HAVE_STACKPROTECTOR if PPC64 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13)
177 select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r2)
178 select HAVE_CONTEXT_TRACKING if PPC64
179 select HAVE_DEBUG_KMEMLEAK
180 select HAVE_DEBUG_STACKOVERFLOW
181 select HAVE_DYNAMIC_FTRACE
182 select HAVE_DYNAMIC_FTRACE_WITH_REGS if MPROFILE_KERNEL
183 select HAVE_EBPF_JIT if PPC64
184 select HAVE_EFFICIENT_UNALIGNED_ACCESS if !(CPU_LITTLE_ENDIAN && POWER7_CPU)
185 select HAVE_FTRACE_MCOUNT_RECORD
186 select HAVE_FUNCTION_ERROR_INJECTION
187 select HAVE_FUNCTION_GRAPH_TRACER
188 select HAVE_FUNCTION_TRACER
189 select HAVE_GCC_PLUGINS if GCC_VERSION >= 50200 # plugin support on gcc <= 5.1 is buggy on PPC
190 select HAVE_GENERIC_GUP
191 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
193 select HAVE_IOREMAP_PROT
194 select HAVE_IRQ_EXIT_ON_IRQ_STACK
195 select HAVE_KERNEL_GZIP
196 select HAVE_KERNEL_XZ if PPC_BOOK3S || 44x
198 select HAVE_KPROBES_ON_FTRACE
199 select HAVE_KRETPROBES
200 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
201 select HAVE_LIVEPATCH if HAVE_DYNAMIC_FTRACE_WITH_REGS
202 select HAVE_MEMBLOCK_NODE_MAP
203 select HAVE_MOD_ARCH_SPECIFIC
204 select HAVE_NMI if PERF_EVENTS || (PPC64 && PPC_BOOK3S)
205 select HAVE_HARDLOCKUP_DETECTOR_ARCH if (PPC64 && PPC_BOOK3S)
207 select HAVE_OPTPROBES if PPC64
208 select HAVE_PERF_EVENTS
209 select HAVE_PERF_EVENTS_NMI if PPC64
210 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
211 select HAVE_PERF_REGS
212 select HAVE_PERF_USER_STACK_DUMP
213 select HAVE_RCU_TABLE_FREE if SMP
214 select HAVE_REGS_AND_STACK_ACCESS_API
215 select HAVE_RELIABLE_STACKTRACE if PPC_BOOK3S_64 && CPU_LITTLE_ENDIAN
216 select HAVE_SYSCALL_TRACEPOINTS
217 select HAVE_VIRT_CPU_ACCOUNTING
218 select HAVE_IRQ_TIME_ACCOUNTING
220 select IOMMU_HELPER if PPC64
222 select IRQ_FORCED_THREADING
223 select MODULES_USE_ELF_RELA
224 select NEED_DMA_MAP_STATE if PPC64 || NOT_COHERENT_CACHE
225 select NEED_SG_DMA_LENGTH
227 select OF_EARLY_FLATTREE
228 select OLD_SIGACTION if PPC32
229 select OLD_SIGSUSPEND
230 select PCI_DOMAINS if PCI
231 select PCI_SYSCALL if PCI
234 select SYSCTL_EXCEPTION_TRACE
235 select THREAD_INFO_IN_TASK
236 select VIRT_TO_BUS if !PPC64
238 # Please keep this list sorted alphabetically.
241 config PPC_BARRIER_NOSPEC
244 depends on PPC_BOOK3S_64 || PPC_FSL_BOOK3E
257 select COMPAT_BINFMT_ELF
258 select ARCH_WANT_OLD_COMPAT_IPC
259 select COMPAT_OLD_SIGACTION
261 config SYSVIPC_COMPAT
263 depends on COMPAT && SYSVIPC
266 config SCHED_OMIT_FRAME_POINTER
270 config ARCH_MAY_HAVE_PC_FDC
274 config PPC_UDBG_16550
277 config GENERIC_TBSYNC
279 default y if PPC32 && SMP
290 config SYS_SUPPORTS_APM_EMULATION
291 default y if PMAC_APM_EMU
297 Used to allow a board to specify it wants an ePAPR compliant wrapper.
299 config DEFAULT_UIMAGE
302 Used to allow a board to specify it wants a uImage built by default
304 config ARCH_HIBERNATION_POSSIBLE
308 config ARCH_SUSPEND_POSSIBLE
310 depends on ADB_PMU || PPC_EFIKA || PPC_LITE5200 || PPC_83xx || \
311 (PPC_85xx && !PPC_E500MC) || PPC_86xx || PPC_PSERIES \
314 config PPC_DCR_NATIVE
322 depends on PPC_DCR_NATIVE || PPC_DCR_MMIO
325 config PPC_OF_PLATFORM_PCI
328 depends on PPC64 # not supported on 32 bits yet
330 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
331 depends on PPC32 || PPC_BOOK3S_64
334 config ARCH_SUPPORTS_UPROBES
337 config PPC_ADV_DEBUG_REGS
339 depends on 40x || BOOKE
342 config PPC_ADV_DEBUG_IACS
344 depends on PPC_ADV_DEBUG_REGS
348 config PPC_ADV_DEBUG_DACS
350 depends on PPC_ADV_DEBUG_REGS
353 config PPC_ADV_DEBUG_DVCS
355 depends on PPC_ADV_DEBUG_REGS
359 config PPC_ADV_DEBUG_DAC_RANGE
361 depends on PPC_ADV_DEBUG_REGS && 44x
366 default y if PPC_BOOK3E_64
368 config PGTABLE_LEVELS
371 default 3 if PPC_64K_PAGES && !PPC_BOOK3S_64
374 source "arch/powerpc/sysdev/Kconfig"
375 source "arch/powerpc/platforms/Kconfig"
377 menu "Kernel options"
380 bool "High memory support"
383 source "kernel/Kconfig.hz"
385 config HUGETLB_PAGE_SIZE_VARIABLE
387 depends on HUGETLB_PAGE
390 config MATH_EMULATION
391 bool "Math emulation"
392 depends on 4xx || PPC_8xx || PPC_MPC832x || BOOKE
394 Some PowerPC chips designed for embedded applications do not have
395 a floating-point unit and therefore do not implement the
396 floating-point instructions in the PowerPC instruction set. If you
397 say Y here, the kernel will include code to emulate a floating-point
398 unit, which will allow programs that use floating-point
401 This is also useful to emulate missing (optional) instructions
402 such as fsqrt on cores that do have an FPU but do not implement
403 them (such as Freescale BookE).
406 prompt "Math emulation options"
407 default MATH_EMULATION_FULL
408 depends on MATH_EMULATION
410 config MATH_EMULATION_FULL
411 bool "Emulate all the floating point instructions"
413 Select this option will enable the kernel to support to emulate
414 all the floating point instructions. If your SoC doesn't have
415 a FPU, you should select this.
417 config MATH_EMULATION_HW_UNIMPLEMENTED
418 bool "Just emulate the FPU unimplemented instructions"
420 Select this if you know there does have a hardware FPU on your
421 SoC, but some floating point instructions are not implemented by that.
425 config PPC_TRANSACTIONAL_MEM
426 bool "Transactional Memory support for POWERPC"
427 depends on PPC_BOOK3S_64
432 Support user-mode Transactional Memory on POWERPC.
434 config LD_HEAD_STUB_CATCH
435 bool "Reserve 256 bytes to cope with linker stubs in HEAD text" if EXPERT
438 Very large kernels can cause linker branch stubs to be generated by
439 code in head_64.S, which moves the head text sections out of their
440 specified location. This option can work around the problem.
444 config MPROFILE_KERNEL
445 depends on PPC64 && CPU_LITTLE_ENDIAN
446 def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__)
449 bool "Support for enabling/disabling CPUs"
450 depends on SMP && (PPC_PSERIES || \
451 PPC_PMAC || PPC_POWERNV || FSL_SOC_BOOKE)
453 Say Y here to be able to disable and re-enable individual
454 CPUs at runtime on SMP machines.
456 Say N if you are unsure.
458 config ARCH_CPU_PROBE_RELEASE
460 depends on HOTPLUG_CPU
462 config ARCH_ENABLE_MEMORY_HOTPLUG
465 config ARCH_ENABLE_MEMORY_HOTREMOVE
468 config PPC64_SUPPORTS_MEMORY_FAILURE
469 bool "Add support for memory hwpoison"
470 depends on PPC_BOOK3S_64
471 default "y" if PPC_POWERNV
472 select ARCH_SUPPORTS_MEMORY_FAILURE
475 bool "kexec system call"
476 depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP)) || PPC_BOOK3E
479 kexec is a system call that implements the ability to shutdown your
480 current kernel, and to start another kernel. It is like a reboot
481 but it is independent of the system firmware. And like a reboot
482 you can start any kernel with it, not just Linux.
484 The name comes from the similarity to the exec system call.
486 It is an ongoing process to be certain the hardware in a machine
487 is properly shutdown, so do not be surprised if this code does not
488 initially work for you. As of this writing the exact hardware
489 interface is strongly in flux, so no good recommendation can be
493 bool "kexec file based system call"
495 select HAVE_IMA_KEXEC
499 depends on CRYPTO_SHA256=y
501 This is a new version of the kexec system call. This call is
502 file based and takes in file descriptors as system call arguments
503 for kernel and initramfs as opposed to a list of segments as is the
504 case for the older kexec call.
506 config ARCH_HAS_KEXEC_PURGATORY
510 bool "Build a relocatable kernel"
511 depends on PPC64 || (FLATMEM && (44x || FSL_BOOKE))
512 select NONSTATIC_KERNEL
513 select MODULE_REL_CRCS if MODVERSIONS
515 This builds a kernel image that is capable of running at the
516 location the kernel is loaded at. For ppc32, there is no any
517 alignment restrictions, and this feature is a superset of
518 DYNAMIC_MEMSTART and hence overrides it. For ppc64, we should use
519 16k-aligned base address. The kernel is linked as a
520 position-independent executable (PIE) and contains dynamic relocations
521 which are processed early in the bootup process.
523 One use is for the kexec on panic case where the recovery kernel
524 must live at a different physical address than the primary
527 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
528 it has been loaded at and the compile time physical addresses
529 CONFIG_PHYSICAL_START is ignored. However CONFIG_PHYSICAL_START
530 setting can still be useful to bootwrappers that need to know the
531 load address of the kernel (eg. u-boot/mkimage).
533 config RELOCATABLE_TEST
534 bool "Test relocatable kernel"
535 depends on (PPC64 && RELOCATABLE)
537 This runs the relocatable kernel at the address it was initially
538 loaded at, which tends to be non-zero and therefore test the
542 bool "Build a dump capture kernel"
543 depends on PPC64 || PPC_BOOK3S_32 || FSL_BOOKE || (44x && !SMP)
544 select RELOCATABLE if PPC64 || 44x || FSL_BOOKE
546 Build a kernel suitable for use as a dump capture kernel.
547 The same kernel binary can be used as production kernel and dump
551 bool "Firmware-assisted dump"
552 depends on PPC64 && PPC_RTAS
556 A robust mechanism to get reliable kernel crash dump with
557 assistance from firmware. This approach does not use kexec,
558 instead firmware assists in booting the capture kernel
559 while preserving memory contents. Firmware-assisted dump
560 is meant to be a kdump replacement offering robustness and
561 speed not possible without system firmware assistance.
566 bool "Distribute interrupts on all CPUs by default"
569 This option gives the kernel permission to distribute IRQs across
570 multiple CPUs. Saying N here will route all IRQs to the first
571 CPU. Generally saying Y is safe, although some problems have been
572 reported with SMP Power Macintoshes with this option enabled.
577 default y if SMP && PPC_PSERIES
583 depends on NEED_MULTIPLE_NODES
585 config USE_PERCPU_NUMA_NODE_ID
589 config HAVE_MEMORYLESS_NODES
593 config ARCH_SELECT_MEMORY_MODEL
597 config ARCH_FLATMEM_ENABLE
599 depends on (PPC64 && !NUMA) || PPC32
601 config ARCH_SPARSEMEM_ENABLE
604 select SPARSEMEM_VMEMMAP_ENABLE
606 config ARCH_SPARSEMEM_DEFAULT
608 depends on PPC_BOOK3S_64
610 config SYS_SUPPORTS_HUGETLBFS
613 config ILLEGAL_POINTER_VALUE
615 # This is roughly half way between the top of user space and the bottom
616 # of kernel space, which seems about as good as we can get.
617 default 0x5deadbeef0000000 if PPC64
620 config ARCH_MEMORY_PROBE
622 depends on MEMORY_HOTPLUG
624 # Some NUMA nodes have memory ranges that span
625 # other nodes. Even though a pfn is valid and
626 # between a node's start and end pfns, it may not
627 # reside on that node. See memmap_init_zone()
629 config NODES_SPAN_OTHER_NODES
631 depends on NEED_MULTIPLE_NODES
634 bool "Using standard binutils settings"
638 Turning this option off allows you to select 256KB PAGE_SIZE on 44x.
639 Note, that kernel will be able to run only those applications,
640 which had been compiled using binutils later than 2.17.50.0.3 with
641 '-zmax-page-size' set to 256K (the default is 64K). Or, if using
642 the older binutils, you can patch them with a trivial patch, which
643 changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000.
649 Select the kernel logical page size. Increasing the page size
650 will reduce software overhead at each page boundary, allow
651 hardware prefetch mechanisms to be more effective, and allow
652 larger dma transfers increasing IO efficiency and reducing
653 overhead. However the utilization of memory will increase.
654 For example, each cached file will using a multiple of the
655 page size to hold its contents and the difference between the
656 end of file and the end of page is wasted.
658 Some dedicated systems, such as software raid serving with
659 accelerated calculations, have shown significant increases.
661 If you configure a 64 bit kernel for 64k pages but the
662 processor does not support them, then the kernel will simulate
663 them with 4k pages, loading them on demand, but with the
664 reduced software overhead and larger internal fragmentation.
665 For the 32 bit kernel, a large page option will not be offered
666 unless it is supported by the configured processor.
668 If unsure, choose 4K_PAGES.
672 select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
676 depends on 44x || PPC_8xx
680 depends on 44x || PPC_BOOK3S_64
681 select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
683 config PPC_256K_PAGES
684 bool "256k page size"
685 depends on 44x && !STDBINUTILS
687 Make the page size 256k.
689 As the ELF standard only requires alignment to support page
690 sizes up to 64k, you will need to compile all of your user
691 space applications with a non-standard binutils settings
692 (see the STDBINUTILS description for details).
694 Say N unless you know what you are doing.
698 config PPC_PAGE_SHIFT
700 default 18 if PPC_256K_PAGES
701 default 16 if PPC_64K_PAGES
702 default 14 if PPC_16K_PAGES
706 int "Thread shift" if EXPERT
708 default "15" if PPC_256K_PAGES
709 default "14" if PPC64
712 Used to define the stack size. The default is almost always what you
713 want. Only change this if you know what you are doing.
715 config ETEXT_SHIFT_BOOL
716 bool "Set custom etext alignment" if STRICT_KERNEL_RWX && \
717 (PPC_BOOK3S_32 || PPC_8xx)
718 depends on ADVANCED_OPTIONS
720 This option allows you to set the kernel end of text alignment. When
721 RAM is mapped by blocks, the alignment needs to fit the size and
722 number of possible blocks. The default should be OK for most configs.
724 Say N here unless you know what you are doing.
727 int "_etext shift" if ETEXT_SHIFT_BOOL
728 range 17 28 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
729 range 19 23 if STRICT_KERNEL_RWX && PPC_8xx
730 default 17 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
731 default 19 if STRICT_KERNEL_RWX && PPC_8xx
732 default PPC_PAGE_SHIFT
734 On Book3S 32 (603+), IBATs are used to map kernel text.
735 Smaller is the alignment, greater is the number of necessary IBATs.
737 On 8xx, large pages (512kb or 8M) are used to map kernel linear
738 memory. Aligning to 8M reduces TLB misses as only 8M pages are used
741 config DATA_SHIFT_BOOL
742 bool "Set custom data alignment" if STRICT_KERNEL_RWX && \
743 (PPC_BOOK3S_32 || PPC_8xx)
744 depends on ADVANCED_OPTIONS
746 This option allows you to set the kernel data alignment. When
747 RAM is mapped by blocks, the alignment needs to fit the size and
748 number of possible blocks. The default should be OK for most configs.
750 Say N here unless you know what you are doing.
753 int "Data shift" if DATA_SHIFT_BOOL
754 default 24 if STRICT_KERNEL_RWX && PPC64
755 range 17 28 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
756 range 19 23 if STRICT_KERNEL_RWX && PPC_8xx
757 default 22 if STRICT_KERNEL_RWX && PPC_BOOK3S_32
758 default 23 if STRICT_KERNEL_RWX && PPC_8xx
759 default PPC_PAGE_SHIFT
761 On Book3S 32 (603+), DBATs are used to map kernel text and rodata RO.
762 Smaller is the alignment, greater is the number of necessary DBATs.
764 On 8xx, large pages (512kb or 8M) are used to map kernel linear
765 memory. Aligning to 8M reduces TLB misses as only 8M pages are used
768 config FORCE_MAX_ZONEORDER
769 int "Maximum zone order"
770 range 8 9 if PPC64 && PPC_64K_PAGES
771 default "9" if PPC64 && PPC_64K_PAGES
772 range 13 13 if PPC64 && !PPC_64K_PAGES
773 default "13" if PPC64 && !PPC_64K_PAGES
774 range 9 64 if PPC32 && PPC_16K_PAGES
775 default "9" if PPC32 && PPC_16K_PAGES
776 range 7 64 if PPC32 && PPC_64K_PAGES
777 default "7" if PPC32 && PPC_64K_PAGES
778 range 5 64 if PPC32 && PPC_256K_PAGES
779 default "5" if PPC32 && PPC_256K_PAGES
783 The kernel memory allocator divides physically contiguous memory
784 blocks into "zones", where each zone is a power of two number of
785 pages. This option selects the largest power of two that the kernel
786 keeps in the memory allocator. If you need to allocate very large
787 blocks of physically contiguous memory, then you may need to
790 This config option is actually maximum order plus one. For example,
791 a value of 11 means that the largest free memory block is 2^10 pages.
793 The page size is not necessarily 4KB. For example, on 64-bit
794 systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep
795 this in mind when choosing a value for this option.
797 config PPC_SUBPAGE_PROT
798 bool "Support setting protections for 4k subpages"
799 depends on PPC_BOOK3S_64 && PPC_64K_PAGES
801 This option adds support for a system call to allow user programs
802 to set access permissions (read/write, readonly, or no access)
803 on the 4k subpages of each 64k page.
805 config PPC_COPRO_BASE
809 bool "SMT (Hyperthreading) scheduler support"
810 depends on PPC64 && SMP
812 SMT scheduler support improves the CPU scheduler's decision making
813 when dealing with POWER5 cpus at a cost of slightly increased
814 overhead in some places. If unsure say N here.
816 config PPC_DENORMALISATION
817 bool "PowerPC denormalisation exception handling"
818 depends on PPC_BOOK3S_64
819 default "y" if PPC_POWERNV
821 Add support for handling denormalisation of single precision
822 values. Useful for bare metal only. If unsure say Y here.
825 bool "Default bootloader kernel arguments"
828 string "Initial kernel command string"
829 depends on CMDLINE_BOOL
830 default "console=ttyS0,9600 console=tty0 root=/dev/sda2"
832 On some platforms, there is currently no way for the boot loader to
833 pass arguments to the kernel. For these platforms, you can supply
834 some command-line options at build time by entering them here. In
835 most cases you will need to specify the root device here.
838 bool "Always use the default kernel command string"
839 depends on CMDLINE_BOOL
841 Always use the default kernel command string, even if the boot
842 loader passes other arguments to the kernel.
843 This is useful if you cannot or don't want to change the
844 command-line options your boot loader passes to the kernel.
847 string "Additional default image types"
849 List additional targets to be built by the bootwrapper here (separated
850 by spaces). This is useful for targets that depend of device tree
851 files in the .dts directory.
853 Targets in this list will be build as part of the default build
854 target, or when the user does a 'make zImage' or a
855 'make zImage.initrd'.
857 If unsure, leave blank
859 config ARCH_WANTS_FREEZER_CONTROL
863 source "kernel/power/Kconfig"
866 bool "Enable seccomp to safely compute untrusted bytecode"
870 This kernel feature is useful for number crunching applications
871 that may need to compute untrusted bytecode during their
872 execution. By using pipes or other transports made available to
873 the process as file descriptors supporting the read/write
874 syscalls, it's possible to isolate those applications in
875 their own address space using seccomp. Once seccomp is
876 enabled via /proc/<pid>/seccomp, it cannot be disabled
877 and the task is only allowed to execute a few safe syscalls
878 defined by each seccomp mode.
880 If unsure, say Y. Only embedded should say N here.
883 prompt "PowerPC Memory Protection Keys"
885 depends on PPC_BOOK3S_64
886 select ARCH_USES_HIGH_VMA_FLAGS
887 select ARCH_HAS_PKEYS
889 Memory Protection Keys provides a mechanism for enforcing
890 page-based protections, but without requiring modification of the
891 page tables when an application changes protection domains.
893 For details, see Documentation/vm/protection-keys.rst
906 bool "Support for ISA-bus hardware"
910 Find out whether you have ISA slots on your motherboard. ISA is the
911 name of a bus system, i.e. the way the CPU talks to the other stuff
912 inside your box. If you have an Apple machine, say N here; if you
913 have an IBM RS/6000 or pSeries machine, say Y. If you have an
914 embedded board, consult your board documentation.
916 config GENERIC_ISA_DMA
918 depends on ISA_DMA_API
921 config PPC_INDIRECT_PCI
924 default y if 40x || 44x
934 select ARCH_HAS_DMA_SET_MASK
935 select PPC_INDIRECT_PCI
941 depends on SUSPEND && (PPC_85xx || PPC_86xx)
943 Freescale MPC85xx/MPC86xx power management controller support
944 (suspend/resume). For MPC83xx see platforms/83xx/suspend.c
949 depends on SUSPEND && (44x || 40x)
951 PPC4xx Clock Power Management (CPM) support (suspend/resume).
952 It also enables support for two different idle states (idle-wait
959 bool "Freescale Local Bus support"
961 Enables reporting of errors from the Freescale local bus
962 controller. Also contains some common code used by
963 drivers for specific local bus peripherals.
967 depends on PPC_83xx || QUICC_ENGINE || CPM2
969 Freescale General-purpose Timers support
973 depends on PCI && 8260
974 select PPC_INDIRECT_PCI
978 bool "Freescale Embedded SRIO Controller support"
979 depends on RAPIDIO = y && HAVE_RAPIDIO
982 Include support for RapidIO controller on Freescale embedded
983 processors (MPC8548, MPC8641, etc).
987 config NONSTATIC_KERNEL
990 menu "Advanced setup"
993 config ADVANCED_OPTIONS
994 bool "Prompt for advanced kernel configuration options"
996 This option will enable prompting for a variety of advanced kernel
997 configuration options. These options can cause the kernel to not
998 work if they are set incorrectly, but can be used to optimize certain
999 aspects of kernel memory management.
1001 Unless you know what you are doing, say N here.
1003 comment "Default settings for advanced configuration options are used"
1004 depends on !ADVANCED_OPTIONS
1006 config LOWMEM_SIZE_BOOL
1007 bool "Set maximum low memory"
1008 depends on ADVANCED_OPTIONS
1010 This option allows you to set the maximum amount of memory which
1011 will be used as "low memory", that is, memory which the kernel can
1012 access directly, without having to set up a kernel virtual mapping.
1013 This can be useful in optimizing the layout of kernel virtual
1016 Say N here unless you know what you are doing.
1019 hex "Maximum low memory size (in bytes)" if LOWMEM_SIZE_BOOL
1020 default "0x30000000"
1022 config LOWMEM_CAM_NUM_BOOL
1023 bool "Set number of CAMs to use to map low memory"
1024 depends on ADVANCED_OPTIONS && FSL_BOOKE
1026 This option allows you to set the maximum number of CAM slots that
1027 will be used to map low memory. There are a limited number of slots
1028 available and even more limited number that will fit in the L1 MMU.
1029 However, using more entries will allow mapping more low memory. This
1030 can be useful in optimizing the layout of kernel virtual memory.
1032 Say N here unless you know what you are doing.
1034 config LOWMEM_CAM_NUM
1035 depends on FSL_BOOKE
1036 int "Number of CAMs to use to map low memory" if LOWMEM_CAM_NUM_BOOL
1039 config DYNAMIC_MEMSTART
1040 bool "Enable page aligned dynamic load address for kernel"
1041 depends on ADVANCED_OPTIONS && FLATMEM && (FSL_BOOKE || 44x)
1042 select NONSTATIC_KERNEL
1044 This option enables the kernel to be loaded at any page aligned
1045 physical address. The kernel creates a mapping from KERNELBASE to
1046 the address where the kernel is loaded. The page size here implies
1047 the TLB page size of the mapping for kernel on the particular platform.
1048 Please refer to the init code for finding the TLB page size.
1050 DYNAMIC_MEMSTART is an easy way of implementing pseudo-RELOCATABLE
1051 kernel image, where the only restriction is the page aligned kernel
1052 load address. When this option is enabled, the compile time physical
1053 address CONFIG_PHYSICAL_START is ignored.
1055 This option is overridden by CONFIG_RELOCATABLE
1057 config PAGE_OFFSET_BOOL
1058 bool "Set custom page offset address"
1059 depends on ADVANCED_OPTIONS
1061 This option allows you to set the kernel virtual address at which
1062 the kernel will map low memory. This can be useful in optimizing
1063 the virtual memory layout of the system.
1065 Say N here unless you know what you are doing.
1068 hex "Virtual address of memory base" if PAGE_OFFSET_BOOL
1069 default "0xc0000000"
1071 config KERNEL_START_BOOL
1072 bool "Set custom kernel base address"
1073 depends on ADVANCED_OPTIONS
1075 This option allows you to set the kernel virtual address at which
1076 the kernel will be loaded. Normally this should match PAGE_OFFSET
1077 however there are times (like kdump) that one might not want them
1080 Say N here unless you know what you are doing.
1083 hex "Virtual address of kernel base" if KERNEL_START_BOOL
1084 default PAGE_OFFSET if PAGE_OFFSET_BOOL
1085 default "0xc2000000" if CRASH_DUMP && !NONSTATIC_KERNEL
1086 default "0xc0000000"
1088 config PHYSICAL_START_BOOL
1089 bool "Set physical address where the kernel is loaded"
1090 depends on ADVANCED_OPTIONS && FLATMEM && FSL_BOOKE
1092 This gives the physical address where the kernel is loaded.
1094 Say N here unless you know what you are doing.
1096 config PHYSICAL_START
1097 hex "Physical address where the kernel is loaded" if PHYSICAL_START_BOOL
1098 default "0x02000000" if PPC_BOOK3S && CRASH_DUMP && !NONSTATIC_KERNEL
1099 default "0x00000000"
1101 config PHYSICAL_ALIGN
1103 default "0x04000000" if FSL_BOOKE
1105 This value puts the alignment restrictions on physical address
1106 where kernel is loaded and run from. Kernel is compiled for an
1107 address which meets above alignment restriction.
1109 config TASK_SIZE_BOOL
1110 bool "Set custom user task size"
1111 depends on ADVANCED_OPTIONS
1113 This option allows you to set the amount of virtual address space
1114 allocated to user tasks. This can be useful in optimizing the
1115 virtual memory layout of the system.
1117 Say N here unless you know what you are doing.
1120 hex "Size of user task space" if TASK_SIZE_BOOL
1121 default "0x80000000" if PPC_8xx
1122 default "0xc0000000"
1124 config CONSISTENT_SIZE_BOOL
1125 bool "Set custom consistent memory pool size"
1126 depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE
1128 This option allows you to set the size of the
1129 consistent memory pool. This pool of virtual memory
1130 is used to make consistent memory allocations.
1132 config CONSISTENT_SIZE
1133 hex "Size of consistent memory pool" if CONSISTENT_SIZE_BOOL
1134 default "0x00200000" if NOT_COHERENT_CACHE
1137 bool "Pinned Kernel TLBs (860 ONLY)"
1138 depends on ADVANCED_OPTIONS && PPC_8xx && \
1139 !DEBUG_PAGEALLOC && !STRICT_KERNEL_RWX
1142 bool "Pinned TLB for DATA"
1147 bool "Pinned TLB for IMMR"
1148 depends on PIN_TLB || PPC_EARLY_DEBUG_CPM
1152 bool "Pinned TLB for TEXT"
1158 # This value must have zeroes in the bottom 60 bits otherwise lots will break
1161 default "0xc000000000000000"
1164 default "0xc000000000000000"
1165 config PHYSICAL_START
1167 default "0x00000000"
1173 config PPC_LIB_RHEAP
1176 source "arch/powerpc/kvm/Kconfig"
1178 source "kernel/livepatch/Kconfig"