1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvaldsconfig ARM 31da177e4SLinus Torvalds bool 41da177e4SLinus Torvalds default y 5942fa985SYury Norov select ARCH_32BIT_OFF_T 6fed240d9SMasami Hiramatsu select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND 7aef0f78eSChristoph Hellwig select ARCH_HAS_BINFMT_FLAT 82792d84eSKees Cook select ARCH_HAS_CURRENT_STACK_POINTER 9c7780ab5SVladimir Murzin select ARCH_HAS_DEBUG_VIRTUAL if MMU 10419e2f18SChristoph Hellwig select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE 112b68f6caSKees Cook select ARCH_HAS_ELF_RANDOMIZE 12ee333554SJinbum Park select ARCH_HAS_FORTIFY_SOURCE 13d8ae8a37SChristoph Hellwig select ARCH_HAS_KEEPINITRD 1475851720SDmitry Vyukov select ARCH_HAS_KCOV 15e69244d2SWill Deacon select ARCH_HAS_MEMBARRIER_SYNC_CORE 160ebeea8cSDaniel Borkmann select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 173010a5eaSLaurent Dufour select ARCH_HAS_PTE_SPECIAL if ARM_LPAE 18ea8c64acSChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 19347cb6afSChristoph Hellwig select ARCH_HAS_SETUP_DMA_OPS 2075851720SDmitry Vyukov select ARCH_HAS_SET_MEMORY 21ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 22ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX if MMU 2331b089bbSChristoph Hellwig select ARCH_HAS_SYNC_DMA_FOR_DEVICE if SWIOTLB || !MMU 2431b089bbSChristoph Hellwig select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB || !MMU 25dc2acdedSChristoph Hellwig select ARCH_HAS_TEARDOWN_DMA_OPS if MMU 263d06770eSMark Rutland select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 27171b3f0dSRussell King select ARCH_HAVE_CUSTOM_GPIO_H 289aaf9bb7SDaniel Thompson select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K 29957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 305e545df3SMike Rapoport select ARCH_KEEP_MEMBLOCK 31d7018848SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 327c703e54SChristoph Hellwig select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN 33ad21fc4fSLaura Abbott select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 34ad21fc4fSLaura Abbott select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7 354badad35SPeter Zijlstra select ARCH_SUPPORTS_ATOMIC_RMW 36855f9a8eSAnshuman Khandual select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE 37017f161aSKim Phillips select ARCH_USE_BUILTIN_BSWAP 380cbad9c9SWill Deacon select ARCH_USE_CMPXCHG_LOCKREF 39dce44566SAnshuman Khandual select ARCH_USE_MEMTEST 40dba79c3dSAlexandre Ghiti select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 4107431506SAnshuman Khandual select ARCH_WANT_GENERAL_HUGETLB 42b1b3f49cSRussell King select ARCH_WANT_IPC_PARSE_VERSION 4359612b24SNathan Chancellor select ARCH_WANT_LD_ORPHAN_WARN 44bdd15a28SChristoph Hellwig select BINFMT_FLAT_ARGVP_ENVP_ON_STACK 4510916706SShile Zhang select BUILDTIME_TABLE_SORT if MMU 46171b3f0dSRussell King select CLONE_BACKWARDS 47f00790aaSRussell King select CPU_PM if SUSPEND || CPU_IDLE 48dce5c9e3SWill Deacon select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS 49ff4c25f2SChristoph Hellwig select DMA_DECLARE_COHERENT 5031b089bbSChristoph Hellwig select DMA_GLOBAL_POOL if !MMU 512f9237d4SChristoph Hellwig select DMA_OPS 52f5ff79fdSChristoph Hellwig select DMA_NONCOHERENT_MMAP if MMU 53b01aec9bSBorislav Petkov select EDAC_SUPPORT 54b01aec9bSBorislav Petkov select EDAC_ATOMIC_SCRUB 5536d0fd21SLaura Abbott select GENERIC_ALLOCATOR 562ef7a295SJuri Lelli select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY 57f00790aaSRussell King select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI 58b1b3f49cSRussell King select GENERIC_CLOCKEVENTS_BROADCAST if SMP 5956afcd3dSMarc Zyngier select GENERIC_IRQ_IPI if SMP 60ea2d9a96SArd Biesheuvel select GENERIC_CPU_AUTOPROBE 612937367bSArd Biesheuvel select GENERIC_EARLY_IOREMAP 62171b3f0dSRussell King select GENERIC_IDLE_POLL_SETUP 63234a0f20SArnd Bergmann select GENERIC_IRQ_MULTI_HANDLER 64b1b3f49cSRussell King select GENERIC_IRQ_PROBE 65b1b3f49cSRussell King select GENERIC_IRQ_SHOW 667c07005eSGeert Uytterhoeven select GENERIC_IRQ_SHOW_LEVEL 67914ee966SPalmer Dabbelt select GENERIC_LIB_DEVMEM_IS_ALLOWED 68b1b3f49cSRussell King select GENERIC_PCI_IOMAP 6938ff87f7SStephen Boyd select GENERIC_SCHED_CLOCK 70b1b3f49cSRussell King select GENERIC_SMP_IDLE_THREAD 71b1b3f49cSRussell King select HARDIRQS_SW_RESEND 72f00790aaSRussell King select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT 730b7857dbSYalin Wang select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 74437682eeSArnd Bergmann select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU 7575969686SWang Kefeng select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL 76437682eeSArnd Bergmann select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU 7742101571SLinus Walleij select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL 78e0c25d95SDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 794f5b0c17SMike Rapoport select HAVE_ARCH_PFN_VALID 80282a181bSYiFei Zhu select HAVE_ARCH_SECCOMP 81f00790aaSRussell King select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT 8208626a60SKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 830693bf68SWade Farnsworth select HAVE_ARCH_TRACEHOOK 84e8003bf6SAnshuman Khandual select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE 85b329f95dSJens Wiklander select HAVE_ARM_SMCCC if CPU_V7 8639c13c20SShubham Bansal select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32 87171b3f0dSRussell King select HAVE_CONTEXT_TRACKING 88b1b3f49cSRussell King select HAVE_C_RECORDMCOUNT 894ed308c4SSteven Rostedt (Google) select HAVE_BUILDTIME_MCOUNT_SORT 90bc420c6cSVincenzo Frascino select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL 91b1b3f49cSRussell King select HAVE_DMA_CONTIGUOUS if MMU 92f00790aaSRussell King select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU 93620176f3SAbel Vesa select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 94dce5c9e3SWill Deacon select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU 955f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 9667a929e0SChristoph Hellwig select HAVE_FAST_GUP if ARM_LPAE 97f00790aaSRussell King select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 9841918ec8SArd Biesheuvel select HAVE_FUNCTION_GRAPH_TRACER 99d6800ca7SArd Biesheuvel select HAVE_FUNCTION_TRACER if !XIP_KERNEL 1006b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 101f00790aaSRussell King select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7) 10287c46b6cSRussell King select HAVE_IRQ_TIME_ACCOUNTING 103b1b3f49cSRussell King select HAVE_KERNEL_GZIP 104f9b493acSKyungsik Lee select HAVE_KERNEL_LZ4 105b1b3f49cSRussell King select HAVE_KERNEL_LZMA 106b1b3f49cSRussell King select HAVE_KERNEL_LZO 107b1b3f49cSRussell King select HAVE_KERNEL_XZ 108cb1293e2SArnd Bergmann select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M 109f00790aaSRussell King select HAVE_KRETPROBES if HAVE_KPROBES 1107d485f64SArd Biesheuvel select HAVE_MOD_ARCH_SPECIFIC 11142a0bb3fSPetr Mladek select HAVE_NMI 1120dc016dbSWang Nan select HAVE_OPTPROBES if !THUMB2_KERNEL 1137ada189fSJamie Iles select HAVE_PERF_EVENTS 11449863894SWill Deacon select HAVE_PERF_REGS 11549863894SWill Deacon select HAVE_PERF_USER_STACK_DUMP 116ff2e6d72SPeter Zijlstra select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE 117e513f8bfSWill Deacon select HAVE_REGS_AND_STACK_ACCESS_API 1189800b9dcSMathieu Desnoyers select HAVE_RSEQ 119d148eac0SMasahiro Yamada select HAVE_STACKPROTECTOR 120b1b3f49cSRussell King select HAVE_SYSCALL_TRACEPOINTS 121af1839ebSCatalin Marinas select HAVE_UID16 12231c1fc81SKevin Hilman select HAVE_VIRT_CPU_ACCOUNTING_GEN 123da0ec6f7SThomas Gleixner select IRQ_FORCED_THREADING 124171b3f0dSRussell King select MODULES_USE_ELF_REL 125f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 126aa7d5f18SArnd Bergmann select OF_EARLY_FLATTREE if OF 127171b3f0dSRussell King select OLD_SIGACTION 128171b3f0dSRussell King select OLD_SIGSUSPEND3 12920f1b79dSChristoph Hellwig select PCI_SYSCALL if PCI 130b1b3f49cSRussell King select PERF_USE_VMALLOC 131b1b3f49cSRussell King select RTC_LIB 132b1b3f49cSRussell King select SYS_SUPPORTS_APM_EMULATION 1339c46929eSArd Biesheuvel select THREAD_INFO_IN_TASK 134d6905849SArd Biesheuvel select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS 1354aae683fSMasahiro Yamada select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M 136171b3f0dSRussell King # Above selects are sorted alphabetically; please add new ones 137171b3f0dSRussell King # according to that. Thanks. 1381da177e4SLinus Torvalds help 1391da177e4SLinus Torvalds The ARM series is a line of low-power-consumption RISC chip designs 140f6c8965aSMartin Michlmayr licensed by ARM Ltd and targeted at embedded applications and 1411da177e4SLinus Torvalds handhelds such as the Compaq IPAQ. ARM-based PCs are no longer 1421da177e4SLinus Torvalds manufactured, but legacy ARM-based PC hardware remains popular in 1431da177e4SLinus Torvalds Europe. There is an ARM Linux project with a web page at 1441da177e4SLinus Torvalds <http://www.arm.linux.org.uk/>. 1451da177e4SLinus Torvalds 146d6905849SArd Biesheuvelconfig ARM_HAS_GROUP_RELOCS 147d6905849SArd Biesheuvel def_bool y 148d6905849SArd Biesheuvel depends on !LD_IS_LLD || LLD_VERSION >= 140000 149d6905849SArd Biesheuvel depends on !COMPILE_TEST 150d6905849SArd Biesheuvel help 151d6905849SArd Biesheuvel Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group 152d6905849SArd Biesheuvel relocations, which have been around for a long time, but were not 153d6905849SArd Biesheuvel supported in LLD until version 14. The combined range is -/+ 256 MiB, 154d6905849SArd Biesheuvel which is usually sufficient, but not for allyesconfig, so we disable 155d6905849SArd Biesheuvel this feature when doing compile testing. 156d6905849SArd Biesheuvel 15774facffeSRussell Kingconfig ARM_HAS_SG_CHAIN 15874facffeSRussell King bool 15974facffeSRussell King 1604ce63fcdSMarek Szyprowskiconfig ARM_DMA_USE_IOMMU 1614ce63fcdSMarek Szyprowski bool 162b1b3f49cSRussell King select ARM_HAS_SG_CHAIN 163b1b3f49cSRussell King select NEED_SG_DMA_LENGTH 1644ce63fcdSMarek Szyprowski 16560460abfSSeung-Woo Kimif ARM_DMA_USE_IOMMU 16660460abfSSeung-Woo Kim 16760460abfSSeung-Woo Kimconfig ARM_DMA_IOMMU_ALIGNMENT 16860460abfSSeung-Woo Kim int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers" 16960460abfSSeung-Woo Kim range 4 9 17060460abfSSeung-Woo Kim default 8 17160460abfSSeung-Woo Kim help 17260460abfSSeung-Woo Kim DMA mapping framework by default aligns all buffers to the smallest 17360460abfSSeung-Woo Kim PAGE_SIZE order which is greater than or equal to the requested buffer 17460460abfSSeung-Woo Kim size. This works well for buffers up to a few hundreds kilobytes, but 17560460abfSSeung-Woo Kim for larger buffers it just a waste of address space. Drivers which has 17660460abfSSeung-Woo Kim relatively small addressing window (like 64Mib) might run out of 17760460abfSSeung-Woo Kim virtual space with just a few allocations. 17860460abfSSeung-Woo Kim 17960460abfSSeung-Woo Kim With this parameter you can specify the maximum PAGE_SIZE order for 18060460abfSSeung-Woo Kim DMA IOMMU buffers. Larger buffers will be aligned only to this 18160460abfSSeung-Woo Kim specified order. The order is expressed as a power of two multiplied 18260460abfSSeung-Woo Kim by the PAGE_SIZE. 18360460abfSSeung-Woo Kim 18460460abfSSeung-Woo Kimendif 18560460abfSSeung-Woo Kim 18675e7153aSRalf Baechleconfig SYS_SUPPORTS_APM_EMULATION 18775e7153aSRalf Baechle bool 18875e7153aSRalf Baechle 189bc581770SLinus Walleijconfig HAVE_TCM 190bc581770SLinus Walleij bool 191bc581770SLinus Walleij select GENERIC_ALLOCATOR 192bc581770SLinus Walleij 193e119bfffSRussell Kingconfig HAVE_PROC_CPU 194e119bfffSRussell King bool 195e119bfffSRussell King 196ce816fa8SUwe Kleine-Königconfig NO_IOPORT_MAP 1975ea81769SAl Viro bool 1985ea81769SAl Viro 1991da177e4SLinus Torvaldsconfig SBUS 2001da177e4SLinus Torvalds bool 2011da177e4SLinus Torvalds 202f16fb1ecSRussell Kingconfig STACKTRACE_SUPPORT 203f16fb1ecSRussell King bool 204f16fb1ecSRussell King default y 205f16fb1ecSRussell King 206f16fb1ecSRussell Kingconfig LOCKDEP_SUPPORT 207f16fb1ecSRussell King bool 208f16fb1ecSRussell King default y 209f16fb1ecSRussell King 210f0d1b0b3SDavid Howellsconfig ARCH_HAS_ILOG2_U32 211f0d1b0b3SDavid Howells bool 212f0d1b0b3SDavid Howells 213f0d1b0b3SDavid Howellsconfig ARCH_HAS_ILOG2_U64 214f0d1b0b3SDavid Howells bool 215f0d1b0b3SDavid Howells 2164a1b5733SEduardo Valentinconfig ARCH_HAS_BANDGAP 2174a1b5733SEduardo Valentin bool 2184a1b5733SEduardo Valentin 219a5f4c561SStefan Agnerconfig FIX_EARLYCON_MEM 220a5f4c561SStefan Agner def_bool y if MMU 221a5f4c561SStefan Agner 222b89c3b16SAkinobu Mitaconfig GENERIC_HWEIGHT 223b89c3b16SAkinobu Mita bool 224b89c3b16SAkinobu Mita default y 225b89c3b16SAkinobu Mita 2261da177e4SLinus Torvaldsconfig GENERIC_CALIBRATE_DELAY 2271da177e4SLinus Torvalds bool 2281da177e4SLinus Torvalds default y 2291da177e4SLinus Torvalds 230a08b6b79Sviro@ZenIV.linux.org.ukconfig ARCH_MAY_HAVE_PC_FDC 231a08b6b79Sviro@ZenIV.linux.org.uk bool 232a08b6b79Sviro@ZenIV.linux.org.uk 233c7edc9e3SDavid A. Longconfig ARCH_SUPPORTS_UPROBES 234c7edc9e3SDavid A. Long def_bool y 235c7edc9e3SDavid A. Long 2361da177e4SLinus Torvaldsconfig GENERIC_ISA_DMA 2371da177e4SLinus Torvalds bool 2381da177e4SLinus Torvalds 2391da177e4SLinus Torvaldsconfig FIQ 2401da177e4SLinus Torvalds bool 2411da177e4SLinus Torvalds 242034d2f5aSAl Viroconfig ARCH_MTD_XIP 243034d2f5aSAl Viro bool 244034d2f5aSAl Viro 245dc21af99SRussell Kingconfig ARM_PATCH_PHYS_VIRT 246c1becedcSRussell King bool "Patch physical to virtual translations at runtime" if EMBEDDED 247c1becedcSRussell King default y 248b511d75dSNicolas Pitre depends on !XIP_KERNEL && MMU 249dc21af99SRussell King help 250111e9a5cSRussell King Patch phys-to-virt and virt-to-phys translation functions at 251111e9a5cSRussell King boot and module load time according to the position of the 252111e9a5cSRussell King kernel in system memory. 253dc21af99SRussell King 254111e9a5cSRussell King This can only be used with non-XIP MMU kernels where the base 2559443076eSArd Biesheuvel of physical memory is at a 2 MiB boundary. 256dc21af99SRussell King 257c1becedcSRussell King Only disable this option if you know that you do not require 258c1becedcSRussell King this feature (eg, building a kernel for a single machine) and 259c1becedcSRussell King you need to shrink the kernel to the minimal size. 260c1becedcSRussell King 261c334bc15SRob Herringconfig NEED_MACH_IO_H 262c334bc15SRob Herring bool 263c334bc15SRob Herring help 264c334bc15SRob Herring Select this when mach/io.h is required to provide special 265c334bc15SRob Herring definitions for this platform. The need for mach/io.h should 266c334bc15SRob Herring be avoided when possible. 267c334bc15SRob Herring 2680cdc8b92SNicolas Pitreconfig NEED_MACH_MEMORY_H 2691b9f95f8SNicolas Pitre bool 270111e9a5cSRussell King help 2710cdc8b92SNicolas Pitre Select this when mach/memory.h is required to provide special 2720cdc8b92SNicolas Pitre definitions for this platform. The need for mach/memory.h should 2730cdc8b92SNicolas Pitre be avoided when possible. 2741b9f95f8SNicolas Pitre 2751b9f95f8SNicolas Pitreconfig PHYS_OFFSET 276974c0724SNicolas Pitre hex "Physical address of main memory" if MMU 277c6f54a9bSUwe Kleine-König depends on !ARM_PATCH_PHYS_VIRT 278974c0724SNicolas Pitre default DRAM_BASE if !MMU 27906954b6aSLinus Walleij default 0x00000000 if ARCH_FOOTBRIDGE 280c6f54a9bSUwe Kleine-König default 0x10000000 if ARCH_OMAP1 || ARCH_RPC 281c6e77bb6SArnd Bergmann default 0x30000000 if ARCH_S3C24XX 282c6e77bb6SArnd Bergmann default 0xa0000000 if ARCH_IOP32X || ARCH_PXA 283c6e77bb6SArnd Bergmann default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100 284c6e77bb6SArnd Bergmann default 0 2851b9f95f8SNicolas Pitre help 2861b9f95f8SNicolas Pitre Please provide the physical address corresponding to the 2871b9f95f8SNicolas Pitre location of main memory in your system. 288cada3c08SRussell King 28987e040b6SSimon Glassconfig GENERIC_BUG 29087e040b6SSimon Glass def_bool y 29187e040b6SSimon Glass depends on BUG 29287e040b6SSimon Glass 2931bcad26eSKirill A. Shutemovconfig PGTABLE_LEVELS 2941bcad26eSKirill A. Shutemov int 2951bcad26eSKirill A. Shutemov default 3 if ARM_LPAE 2961bcad26eSKirill A. Shutemov default 2 2971bcad26eSKirill A. Shutemov 2981da177e4SLinus Torvaldsmenu "System Type" 2991da177e4SLinus Torvalds 3003c427975SHyok S. Choiconfig MMU 3013c427975SHyok S. Choi bool "MMU-based Paged Memory Management Support" 3023c427975SHyok S. Choi default y 3033c427975SHyok S. Choi help 3043c427975SHyok S. Choi Select if you want MMU-based virtualised addressing space 3053c427975SHyok S. Choi support by paged memory management. If unsure, say 'Y'. 3063c427975SHyok S. Choi 3072f618d5eSArnd Bergmannconfig ARM_SINGLE_ARMV7M 3082f618d5eSArnd Bergmann def_bool !MMU 3092f618d5eSArnd Bergmann select ARM_NVIC 3102f618d5eSArnd Bergmann select AUTO_ZRELADDR 3112f618d5eSArnd Bergmann select TIMER_OF 3122f618d5eSArnd Bergmann select COMMON_CLK 3132f618d5eSArnd Bergmann select CPU_V7M 3142f618d5eSArnd Bergmann select NO_IOPORT_MAP 3152f618d5eSArnd Bergmann select SPARSE_IRQ 3162f618d5eSArnd Bergmann select USE_OF 3172f618d5eSArnd Bergmann 318e0c25d95SDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 319e0c25d95SDaniel Cashman default 8 320e0c25d95SDaniel Cashman 321e0c25d95SDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 322e0c25d95SDaniel Cashman default 14 if PAGE_OFFSET=0x40000000 323e0c25d95SDaniel Cashman default 15 if PAGE_OFFSET=0x80000000 324e0c25d95SDaniel Cashman default 16 325e0c25d95SDaniel Cashman 326ccf50e23SRussell King# 327ccf50e23SRussell King# The "ARM system type" choice list is ordered alphabetically by option 328ccf50e23SRussell King# text. Please add new entries in the option alphabetic order. 329ccf50e23SRussell King# 3301da177e4SLinus Torvaldschoice 3311da177e4SLinus Torvalds prompt "ARM system type" 3322f618d5eSArnd Bergmann depends on MMU 3332f618d5eSArnd Bergmann default ARCH_MULTIPLATFORM 3341da177e4SLinus Torvalds 335387798b3SRob Herringconfig ARCH_MULTIPLATFORM 336387798b3SRob Herring bool "Allow multiple platforms to be selected" 337fb597f2aSGregory Fong select ARCH_FLATMEM_ENABLE 338fb597f2aSGregory Fong select ARCH_SPARSEMEM_ENABLE 339fb597f2aSGregory Fong select ARCH_SELECT_MEMORY_MODEL 34042dc836dSOlof Johansson select ARM_HAS_SG_CHAIN 341387798b3SRob Herring select ARM_PATCH_PHYS_VIRT 342387798b3SRob Herring select AUTO_ZRELADDR 343bb0eb050SDaniel Lezcano select TIMER_OF 34466314223SDinh Nguyen select COMMON_CLK 345eb01d42aSChristoph Hellwig select HAVE_PCI 3462eac9c2dSChristoph Hellwig select PCI_DOMAINS_GENERIC if PCI 34766314223SDinh Nguyen select SPARSE_IRQ 34866314223SDinh Nguyen select USE_OF 34966314223SDinh Nguyen 3501da177e4SLinus Torvaldsconfig ARCH_FOOTBRIDGE 3511da177e4SLinus Torvalds bool "FootBridge" 3525d6f5267SArnd Bergmann depends on CPU_LITTLE_ENDIAN 353*96a4ce30SArnd Bergmann depends on ATAGS 354c750815eSRussell King select CPU_SA110 3551da177e4SLinus Torvalds select FOOTBRIDGE 3560cdc8b92SNicolas Pitre select NEED_MACH_MEMORY_H 357f999b8bdSMartin Michlmayr help 358f999b8bdSMartin Michlmayr Support for systems based on the DC21285 companion chip 359f999b8bdSMartin Michlmayr ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder. 3601da177e4SLinus Torvalds 3611da177e4SLinus Torvaldsconfig ARCH_RPC 3621da177e4SLinus Torvalds bool "RiscPC" 3632abd6e34SArnd Bergmann depends on !CC_IS_CLANG && GCC_VERSION < 90100 && GCC_VERSION >= 60000 3645d6f5267SArnd Bergmann depends on CPU_LITTLE_ENDIAN 365*96a4ce30SArnd Bergmann depends on ATAGS 3661da177e4SLinus Torvalds select ARCH_ACORN 367a08b6b79Sviro@ZenIV.linux.org.uk select ARCH_MAY_HAVE_PC_FDC 36807f841b7SRussell King select ARCH_SPARSEMEM_ENABLE 3690b40deeeSRussell King select ARM_HAS_SG_CHAIN 370fa04e209SArnd Bergmann select CPU_SA110 371b1b3f49cSRussell King select FIQ 372b1b3f49cSRussell King select HAVE_PATA_PLATFORM 373b1b3f49cSRussell King select ISA_DMA_API 3746239da29SArnd Bergmann select LEGACY_TIMER_TICK 375c334bc15SRob Herring select NEED_MACH_IO_H 3760cdc8b92SNicolas Pitre select NEED_MACH_MEMORY_H 377ce816fa8SUwe Kleine-König select NO_IOPORT_MAP 3781da177e4SLinus Torvalds help 3791da177e4SLinus Torvalds On the Acorn Risc-PC, Linux can support the internal IDE disk and 3801da177e4SLinus Torvalds CD-ROM interface, serial and parallel port, and the floppy drive. 3811da177e4SLinus Torvalds 3821da177e4SLinus Torvaldsconfig ARCH_SA1100 3831da177e4SLinus Torvalds bool "SA1100-based" 3845d6f5267SArnd Bergmann depends on CPU_LITTLE_ENDIAN 385*96a4ce30SArnd Bergmann depends on ATAGS 386b1b3f49cSRussell King select ARCH_MTD_XIP 387b1b3f49cSRussell King select ARCH_SPARSEMEM_ENABLE 388b1b3f49cSRussell King select CLKSRC_MMIO 389389d9b58SDaniel Lezcano select CLKSRC_PXA 390bb0eb050SDaniel Lezcano select TIMER_OF if OF 391d6c82046SRussell King select COMMON_CLK 392b1b3f49cSRussell King select CPU_FREQ 393b1b3f49cSRussell King select CPU_SA1100 3945c34a4e8SLinus Walleij select GPIOLIB 3951eca42b4SDmitry Eremin-Solenikov select IRQ_DOMAIN 396b1b3f49cSRussell King select ISA 3970cdc8b92SNicolas Pitre select NEED_MACH_MEMORY_H 398375dec92SRussell King select SPARSE_IRQ 399f999b8bdSMartin Michlmayr help 400f999b8bdSMartin Michlmayr Support for StrongARM 11x0 based boards. 4011da177e4SLinus Torvalds 4021da177e4SLinus Torvaldsendchoice 4031da177e4SLinus Torvalds 404387798b3SRob Herringmenu "Multiple platform selection" 405387798b3SRob Herring depends on ARCH_MULTIPLATFORM 406387798b3SRob Herring 407387798b3SRob Herringcomment "CPU Core family selection" 408387798b3SRob Herring 409f8afae40SArnd Bergmannconfig ARCH_MULTI_V4 410f8afae40SArnd Bergmann bool "ARMv4 based platforms (FA526)" 411f8afae40SArnd Bergmann depends on !ARCH_MULTI_V6_V7 412f8afae40SArnd Bergmann select ARCH_MULTI_V4_V5 413f8afae40SArnd Bergmann select CPU_FA526 414f8afae40SArnd Bergmann 415387798b3SRob Herringconfig ARCH_MULTI_V4T 416387798b3SRob Herring bool "ARMv4T based platforms (ARM720T, ARM920T, ...)" 417387798b3SRob Herring depends on !ARCH_MULTI_V6_V7 418b1b3f49cSRussell King select ARCH_MULTI_V4_V5 41924e860fbSArnd Bergmann select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \ 42024e860fbSArnd Bergmann CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \ 42124e860fbSArnd Bergmann CPU_ARM925T || CPU_ARM940T) 422387798b3SRob Herring 423387798b3SRob Herringconfig ARCH_MULTI_V5 424387798b3SRob Herring bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)" 425387798b3SRob Herring depends on !ARCH_MULTI_V6_V7 426b1b3f49cSRussell King select ARCH_MULTI_V4_V5 42712567bbdSAndrew Lunn select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \ 42824e860fbSArnd Bergmann CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \ 42924e860fbSArnd Bergmann CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON) 430387798b3SRob Herring 431387798b3SRob Herringconfig ARCH_MULTI_V4_V5 432387798b3SRob Herring bool 433387798b3SRob Herring 434387798b3SRob Herringconfig ARCH_MULTI_V6 4358dda05ccSStephen Boyd bool "ARMv6 based platforms (ARM11)" 436387798b3SRob Herring select ARCH_MULTI_V6_V7 43742f4754aSRob Herring select CPU_V6K 438387798b3SRob Herring 439387798b3SRob Herringconfig ARCH_MULTI_V7 4408dda05ccSStephen Boyd bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)" 441387798b3SRob Herring default y 442387798b3SRob Herring select ARCH_MULTI_V6_V7 443b1b3f49cSRussell King select CPU_V7 44490bc8ac7SRob Herring select HAVE_SMP 445387798b3SRob Herring 446387798b3SRob Herringconfig ARCH_MULTI_V6_V7 447387798b3SRob Herring bool 4489352b05bSRob Herring select MIGHT_HAVE_CACHE_L2X0 449387798b3SRob Herring 450387798b3SRob Herringconfig ARCH_MULTI_CPU_AUTO 451387798b3SRob Herring def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7) 452387798b3SRob Herring select ARCH_MULTI_V5 453387798b3SRob Herring 454387798b3SRob Herringendmenu 455387798b3SRob Herring 45605e2a3deSRob Herringconfig ARCH_VIRT 457e3246542SMasahiro Yamada bool "Dummy Virtual Machine" 458e3246542SMasahiro Yamada depends on ARCH_MULTI_V7 4594b8b5f25SRob Herring select ARM_AMBA 46005e2a3deSRob Herring select ARM_GIC 4613ee80364SArnd Bergmann select ARM_GIC_V2M if PCI 4620b28f1dbSJean-Philippe Brucker select ARM_GIC_V3 463bb29cecbSVladimir Murzin select ARM_GIC_V3_ITS if PCI 46405e2a3deSRob Herring select ARM_PSCI 4654b8b5f25SRob Herring select HAVE_ARM_ARCH_TIMER 46605e2a3deSRob Herring 4672cf1c348SJohn Crispinconfig ARCH_AIROHA 4682cf1c348SJohn Crispin bool "Airoha SoC Support" 4692cf1c348SJohn Crispin depends on ARCH_MULTI_V7 4702cf1c348SJohn Crispin select ARM_AMBA 4712cf1c348SJohn Crispin select ARM_GIC 4722cf1c348SJohn Crispin select ARM_GIC_V3 4732cf1c348SJohn Crispin select ARM_PSCI 4742cf1c348SJohn Crispin select HAVE_ARM_ARCH_TIMER 4752cf1c348SJohn Crispin select COMMON_CLK 4762cf1c348SJohn Crispin help 4772cf1c348SJohn Crispin Support for Airoha EN7523 SoCs 4782cf1c348SJohn Crispin 479ccf50e23SRussell King# 480ccf50e23SRussell King# This is sorted alphabetically by mach-* pathname. However, plat-* 481ccf50e23SRussell King# Kconfigs may be included either alphabetically (according to the 482ccf50e23SRussell King# plat- suffix) or along side the corresponding mach-* source. 483ccf50e23SRussell King# 4846bb8536cSAndreas Färbersource "arch/arm/mach-actions/Kconfig" 4856bb8536cSAndreas Färber 486445d9b30STsahee Zidenbergsource "arch/arm/mach-alpine/Kconfig" 487445d9b30STsahee Zidenberg 488590b460cSLars Perssonsource "arch/arm/mach-artpec/Kconfig" 489590b460cSLars Persson 490d9bfc86dSOleksij Rempelsource "arch/arm/mach-asm9260/Kconfig" 491d9bfc86dSOleksij Rempel 492a66c51f9SAlexandre Bellonisource "arch/arm/mach-aspeed/Kconfig" 493a66c51f9SAlexandre Belloni 49495b8f20fSRussell Kingsource "arch/arm/mach-at91/Kconfig" 49595b8f20fSRussell King 4961d22924eSAnders Bergsource "arch/arm/mach-axxia/Kconfig" 4971d22924eSAnders Berg 4988ac49e04SChristian Daudtsource "arch/arm/mach-bcm/Kconfig" 4998ac49e04SChristian Daudt 5001c37fa10SSebastian Hesselbarthsource "arch/arm/mach-berlin/Kconfig" 5011c37fa10SSebastian Hesselbarth 5021da177e4SLinus Torvaldssource "arch/arm/mach-clps711x/Kconfig" 5031da177e4SLinus Torvalds 504d94f944eSAnton Vorontsovsource "arch/arm/mach-cns3xxx/Kconfig" 505d94f944eSAnton Vorontsov 50695b8f20fSRussell Kingsource "arch/arm/mach-davinci/Kconfig" 50795b8f20fSRussell King 508df8d742eSBaruch Siachsource "arch/arm/mach-digicolor/Kconfig" 509df8d742eSBaruch Siach 51095b8f20fSRussell Kingsource "arch/arm/mach-dove/Kconfig" 51195b8f20fSRussell King 512e7736d47SLennert Buytenheksource "arch/arm/mach-ep93xx/Kconfig" 513e7736d47SLennert Buytenhek 514a66c51f9SAlexandre Bellonisource "arch/arm/mach-exynos/Kconfig" 515a66c51f9SAlexandre Belloni 5161da177e4SLinus Torvaldssource "arch/arm/mach-footbridge/Kconfig" 5171da177e4SLinus Torvalds 51859d3a193SPaulius Zaleckassource "arch/arm/mach-gemini/Kconfig" 51959d3a193SPaulius Zaleckas 520387798b3SRob Herringsource "arch/arm/mach-highbank/Kconfig" 521387798b3SRob Herring 522389ee0c2SHaojian Zhuangsource "arch/arm/mach-hisi/Kconfig" 523389ee0c2SHaojian Zhuang 52411d89440SNick Hawkinssource "arch/arm/mach-hpe/Kconfig" 52511d89440SNick Hawkins 526a66c51f9SAlexandre Bellonisource "arch/arm/mach-imx/Kconfig" 527a66c51f9SAlexandre Belloni 5283f7e5815SLennert Buytenheksource "arch/arm/mach-iop32x/Kconfig" 5293f7e5815SLennert Buytenhek 5301da177e4SLinus Torvaldssource "arch/arm/mach-ixp4xx/Kconfig" 5311da177e4SLinus Torvalds 532828989adSSantosh Shilimkarsource "arch/arm/mach-keystone/Kconfig" 533828989adSSantosh Shilimkar 53475bf1bd7SArnd Bergmannsource "arch/arm/mach-lpc32xx/Kconfig" 53595b8f20fSRussell King 536a66c51f9SAlexandre Bellonisource "arch/arm/mach-mediatek/Kconfig" 537a66c51f9SAlexandre Belloni 5383b8f5030SCarlo Caionesource "arch/arm/mach-meson/Kconfig" 5393b8f5030SCarlo Caione 5409fb29c73SSugaya Taichisource "arch/arm/mach-milbeaut/Kconfig" 5419fb29c73SSugaya Taichi 542a66c51f9SAlexandre Bellonisource "arch/arm/mach-mmp/Kconfig" 543a66c51f9SAlexandre Belloni 54417723fd3SJonas Jensensource "arch/arm/mach-moxart/Kconfig" 54517723fd3SJonas Jensen 546312b62b6SDaniel Palmersource "arch/arm/mach-mstar/Kconfig" 547312b62b6SDaniel Palmer 548794d15b2SStanislav Samsonovsource "arch/arm/mach-mv78xx0/Kconfig" 549794d15b2SStanislav Samsonov 550a66c51f9SAlexandre Bellonisource "arch/arm/mach-mvebu/Kconfig" 551f682a218SMatthias Brugger 5521d3f33d5SShawn Guosource "arch/arm/mach-mxs/Kconfig" 5531d3f33d5SShawn Guo 55495b8f20fSRussell Kingsource "arch/arm/mach-nomadik/Kconfig" 55595b8f20fSRussell King 5567bffa14cSBrendan Higginssource "arch/arm/mach-npcm/Kconfig" 5577bffa14cSBrendan Higgins 5589851ca57SDaniel Tangsource "arch/arm/mach-nspire/Kconfig" 5599851ca57SDaniel Tang 560d48af15eSTony Lindgrensource "arch/arm/mach-omap1/Kconfig" 5611da177e4SLinus Torvalds 5621dbae815STony Lindgrensource "arch/arm/mach-omap2/Kconfig" 5631dbae815STony Lindgren 5649dd0b194SLennert Buytenheksource "arch/arm/mach-orion5x/Kconfig" 565585cf175STzachi Perelstein 566a66c51f9SAlexandre Bellonisource "arch/arm/mach-oxnas/Kconfig" 567a66c51f9SAlexandre Belloni 56895b8f20fSRussell Kingsource "arch/arm/mach-pxa/Kconfig" 5691da177e4SLinus Torvalds 5708fc1b0f8SKumar Galasource "arch/arm/mach-qcom/Kconfig" 5718fc1b0f8SKumar Gala 57278e3dbc1SAndreas Färbersource "arch/arm/mach-rda/Kconfig" 57378e3dbc1SAndreas Färber 57486aeee4dSAndreas Färbersource "arch/arm/mach-realtek/Kconfig" 57586aeee4dSAndreas Färber 576d63dc051SHeiko Stuebnersource "arch/arm/mach-rockchip/Kconfig" 577d63dc051SHeiko Stuebner 57871b9114dSArnd Bergmannsource "arch/arm/mach-s3c/Kconfig" 579a66c51f9SAlexandre Belloni 580a66c51f9SAlexandre Bellonisource "arch/arm/mach-s5pv210/Kconfig" 581a66c51f9SAlexandre Belloni 58295b8f20fSRussell Kingsource "arch/arm/mach-sa1100/Kconfig" 583edabd38eSSaeed Bishara 584a66c51f9SAlexandre Bellonisource "arch/arm/mach-shmobile/Kconfig" 585a66c51f9SAlexandre Belloni 586387798b3SRob Herringsource "arch/arm/mach-socfpga/Kconfig" 587387798b3SRob Herring 588a7ed099fSArnd Bergmannsource "arch/arm/mach-spear/Kconfig" 589a21765a7SBen Dooks 59065ebcc11SSrinivas Kandagatlasource "arch/arm/mach-sti/Kconfig" 59165ebcc11SSrinivas Kandagatla 592bcb84fb4SAlexandre TORGUEsource "arch/arm/mach-stm32/Kconfig" 593bcb84fb4SAlexandre TORGUE 5943b52634fSMaxime Ripardsource "arch/arm/mach-sunxi/Kconfig" 5953b52634fSMaxime Ripard 596c5f80065SErik Gillingsource "arch/arm/mach-tegra/Kconfig" 597c5f80065SErik Gilling 598ba56a987SMasahiro Yamadasource "arch/arm/mach-uniphier/Kconfig" 599ba56a987SMasahiro Yamada 60095b8f20fSRussell Kingsource "arch/arm/mach-ux500/Kconfig" 6011da177e4SLinus Torvalds 6021da177e4SLinus Torvaldssource "arch/arm/mach-versatile/Kconfig" 6031da177e4SLinus Torvalds 6046f35f9a9STony Prisksource "arch/arm/mach-vt8500/Kconfig" 6056f35f9a9STony Prisk 6069a45eb69SJosh Cartwrightsource "arch/arm/mach-zynq/Kconfig" 6079a45eb69SJosh Cartwright 608499f1640SStefan Agner# ARMv7-M architecture 609499f1640SStefan Agnerconfig ARCH_LPC18XX 610499f1640SStefan Agner bool "NXP LPC18xx/LPC43xx" 611499f1640SStefan Agner depends on ARM_SINGLE_ARMV7M 612499f1640SStefan Agner select ARCH_HAS_RESET_CONTROLLER 613499f1640SStefan Agner select ARM_AMBA 614499f1640SStefan Agner select CLKSRC_LPC32XX 615499f1640SStefan Agner select PINCTRL 616499f1640SStefan Agner help 617499f1640SStefan Agner Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4 618499f1640SStefan Agner high performance microcontrollers. 619499f1640SStefan Agner 6201847119dSVladimir Murzinconfig ARCH_MPS2 62117bd274eSBaruch Siach bool "ARM MPS2 platform" 6221847119dSVladimir Murzin depends on ARM_SINGLE_ARMV7M 6231847119dSVladimir Murzin select ARM_AMBA 6241847119dSVladimir Murzin select CLKSRC_MPS2 6251847119dSVladimir Murzin help 6261847119dSVladimir Murzin Support for Cortex-M Prototyping System (or V2M-MPS2) which comes 6271847119dSVladimir Murzin with a range of available cores like Cortex-M3/M4/M7. 6281847119dSVladimir Murzin 6291847119dSVladimir Murzin Please, note that depends which Application Note is used memory map 6301847119dSVladimir Murzin for the platform may vary, so adjustment of RAM base might be needed. 6311847119dSVladimir Murzin 6321da177e4SLinus Torvalds# Definitions to make life easier 6331da177e4SLinus Torvaldsconfig ARCH_ACORN 6341da177e4SLinus Torvalds bool 6351da177e4SLinus Torvalds 63669b02f6aSLennert Buytenhekconfig PLAT_ORION 63769b02f6aSLennert Buytenhek bool 638bfe45e0bSRussell King select CLKSRC_MMIO 639b1b3f49cSRussell King select COMMON_CLK 640dc7ad3b3SRussell King select GENERIC_IRQ_CHIP 641278b45b0SAndrew Lunn select IRQ_DOMAIN 64269b02f6aSLennert Buytenhek 643abcda1dcSThomas Petazzoniconfig PLAT_ORION_LEGACY 644abcda1dcSThomas Petazzoni bool 645abcda1dcSThomas Petazzoni select PLAT_ORION 646abcda1dcSThomas Petazzoni 647f4b8b319SRussell Kingconfig PLAT_VERSATILE 648f4b8b319SRussell King bool 649f4b8b319SRussell King 6508636a1f9SMasahiro Yamadasource "arch/arm/mm/Kconfig" 6511da177e4SLinus Torvalds 652afe4b25eSLennert Buytenhekconfig IWMMXT 653d93003e8SSebastian Hesselbarth bool "Enable iWMMXt support" 654d93003e8SSebastian Hesselbarth depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B 655d93003e8SSebastian Hesselbarth default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B 656afe4b25eSLennert Buytenhek help 657afe4b25eSLennert Buytenhek Enable support for iWMMXt context switching at run time if 658afe4b25eSLennert Buytenhek running on a CPU that supports it. 659afe4b25eSLennert Buytenhek 6603b93e7b0SHyok S. Choiif !MMU 6613b93e7b0SHyok S. Choisource "arch/arm/Kconfig-nommu" 6623b93e7b0SHyok S. Choiendif 6633b93e7b0SHyok S. Choi 6643e0a07f8SGregory CLEMENTconfig PJ4B_ERRATA_4742 6653e0a07f8SGregory CLEMENT bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation" 6663e0a07f8SGregory CLEMENT depends on CPU_PJ4B && MACH_ARMADA_370 6673e0a07f8SGregory CLEMENT default y 6683e0a07f8SGregory CLEMENT help 6693e0a07f8SGregory CLEMENT When coming out of either a Wait for Interrupt (WFI) or a Wait for 6703e0a07f8SGregory CLEMENT Event (WFE) IDLE states, a specific timing sensitivity exists between 6713e0a07f8SGregory CLEMENT the retiring WFI/WFE instructions and the newly issued subsequent 6723e0a07f8SGregory CLEMENT instructions. This sensitivity can result in a CPU hang scenario. 6733e0a07f8SGregory CLEMENT Workaround: 6743e0a07f8SGregory CLEMENT The software must insert either a Data Synchronization Barrier (DSB) 6753e0a07f8SGregory CLEMENT or Data Memory Barrier (DMB) command immediately after the WFI/WFE 6763e0a07f8SGregory CLEMENT instruction 6773e0a07f8SGregory CLEMENT 678f0c4b8d6SWill Deaconconfig ARM_ERRATA_326103 679f0c4b8d6SWill Deacon bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory" 680f0c4b8d6SWill Deacon depends on CPU_V6 681f0c4b8d6SWill Deacon help 682f0c4b8d6SWill Deacon Executing a SWP instruction to read-only memory does not set bit 11 683f0c4b8d6SWill Deacon of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to 684f0c4b8d6SWill Deacon treat the access as a read, preventing a COW from occurring and 685f0c4b8d6SWill Deacon causing the faulting task to livelock. 686f0c4b8d6SWill Deacon 6879cba3cccSCatalin Marinasconfig ARM_ERRATA_411920 6889cba3cccSCatalin Marinas bool "ARM errata: Invalidation of the Instruction Cache operation can fail" 689e399b1a4SRussell King depends on CPU_V6 || CPU_V6K 6909cba3cccSCatalin Marinas help 6919cba3cccSCatalin Marinas Invalidation of the Instruction Cache operation can 6929cba3cccSCatalin Marinas fail. This erratum is present in 1136 (before r1p4), 1156 and 1176. 6939cba3cccSCatalin Marinas It does not affect the MPCore. This option enables the ARM Ltd. 6949cba3cccSCatalin Marinas recommended workaround. 6959cba3cccSCatalin Marinas 6967ce236fcSCatalin Marinasconfig ARM_ERRATA_430973 6977ce236fcSCatalin Marinas bool "ARM errata: Stale prediction on replaced interworking branch" 6987ce236fcSCatalin Marinas depends on CPU_V7 6997ce236fcSCatalin Marinas help 7007ce236fcSCatalin Marinas This option enables the workaround for the 430973 Cortex-A8 70179403cdaSRussell King r1p* erratum. If a code sequence containing an ARM/Thumb 7027ce236fcSCatalin Marinas interworking branch is replaced with another code sequence at the 7037ce236fcSCatalin Marinas same virtual address, whether due to self-modifying code or virtual 7047ce236fcSCatalin Marinas to physical address re-mapping, Cortex-A8 does not recover from the 7057ce236fcSCatalin Marinas stale interworking branch prediction. This results in Cortex-A8 7067ce236fcSCatalin Marinas executing the new code sequence in the incorrect ARM or Thumb state. 7077ce236fcSCatalin Marinas The workaround enables the BTB/BTAC operations by setting ACTLR.IBE 7087ce236fcSCatalin Marinas and also flushes the branch target cache at every context switch. 7097ce236fcSCatalin Marinas Note that setting specific bits in the ACTLR register may not be 7107ce236fcSCatalin Marinas available in non-secure mode. 7117ce236fcSCatalin Marinas 712855c551fSCatalin Marinasconfig ARM_ERRATA_458693 713855c551fSCatalin Marinas bool "ARM errata: Processor deadlock when a false hazard is created" 714855c551fSCatalin Marinas depends on CPU_V7 71562e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 716855c551fSCatalin Marinas help 717855c551fSCatalin Marinas This option enables the workaround for the 458693 Cortex-A8 (r2p0) 718855c551fSCatalin Marinas erratum. For very specific sequences of memory operations, it is 719855c551fSCatalin Marinas possible for a hazard condition intended for a cache line to instead 720855c551fSCatalin Marinas be incorrectly associated with a different cache line. This false 721855c551fSCatalin Marinas hazard might then cause a processor deadlock. The workaround enables 722855c551fSCatalin Marinas the L1 caching of the NEON accesses and disables the PLD instruction 723855c551fSCatalin Marinas in the ACTLR register. Note that setting specific bits in the ACTLR 724855c551fSCatalin Marinas register may not be available in non-secure mode. 725855c551fSCatalin Marinas 7260516e464SCatalin Marinasconfig ARM_ERRATA_460075 7270516e464SCatalin Marinas bool "ARM errata: Data written to the L2 cache can be overwritten with stale data" 7280516e464SCatalin Marinas depends on CPU_V7 72962e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 7300516e464SCatalin Marinas help 7310516e464SCatalin Marinas This option enables the workaround for the 460075 Cortex-A8 (r2p0) 7320516e464SCatalin Marinas erratum. Any asynchronous access to the L2 cache may encounter a 7330516e464SCatalin Marinas situation in which recent store transactions to the L2 cache are lost 7340516e464SCatalin Marinas and overwritten with stale memory contents from external memory. The 7350516e464SCatalin Marinas workaround disables the write-allocate mode for the L2 cache via the 7360516e464SCatalin Marinas ACTLR register. Note that setting specific bits in the ACTLR register 7370516e464SCatalin Marinas may not be available in non-secure mode. 7380516e464SCatalin Marinas 7399f05027cSWill Deaconconfig ARM_ERRATA_742230 7409f05027cSWill Deacon bool "ARM errata: DMB operation may be faulty" 7419f05027cSWill Deacon depends on CPU_V7 && SMP 74262e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 7439f05027cSWill Deacon help 7449f05027cSWill Deacon This option enables the workaround for the 742230 Cortex-A9 7459f05027cSWill Deacon (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction 7469f05027cSWill Deacon between two write operations may not ensure the correct visibility 7479f05027cSWill Deacon ordering of the two writes. This workaround sets a specific bit in 7489f05027cSWill Deacon the diagnostic register of the Cortex-A9 which causes the DMB 7499f05027cSWill Deacon instruction to behave as a DSB, ensuring the correct behaviour of 7509f05027cSWill Deacon the two writes. 7519f05027cSWill Deacon 752a672e99bSWill Deaconconfig ARM_ERRATA_742231 753a672e99bSWill Deacon bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption" 754a672e99bSWill Deacon depends on CPU_V7 && SMP 75562e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 756a672e99bSWill Deacon help 757a672e99bSWill Deacon This option enables the workaround for the 742231 Cortex-A9 758a672e99bSWill Deacon (r2p0..r2p2) erratum. Under certain conditions, specific to the 759a672e99bSWill Deacon Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode, 760a672e99bSWill Deacon accessing some data located in the same cache line, may get corrupted 761a672e99bSWill Deacon data due to bad handling of the address hazard when the line gets 762a672e99bSWill Deacon replaced from one of the CPUs at the same time as another CPU is 763a672e99bSWill Deacon accessing it. This workaround sets specific bits in the diagnostic 764a672e99bSWill Deacon register of the Cortex-A9 which reduces the linefill issuing 765a672e99bSWill Deacon capabilities of the processor. 766a672e99bSWill Deacon 76769155794SJon Medhurstconfig ARM_ERRATA_643719 76869155794SJon Medhurst bool "ARM errata: LoUIS bit field in CLIDR register is incorrect" 76969155794SJon Medhurst depends on CPU_V7 && SMP 770e5a5de44SRussell King default y 77169155794SJon Medhurst help 77269155794SJon Medhurst This option enables the workaround for the 643719 Cortex-A9 (prior to 77369155794SJon Medhurst r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR 77469155794SJon Medhurst register returns zero when it should return one. The workaround 77569155794SJon Medhurst corrects this value, ensuring cache maintenance operations which use 77669155794SJon Medhurst it behave as intended and avoiding data corruption. 77769155794SJon Medhurst 778cdf357f1SWill Deaconconfig ARM_ERRATA_720789 779cdf357f1SWill Deacon bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID" 780e66dc745SDave Martin depends on CPU_V7 781cdf357f1SWill Deacon help 782cdf357f1SWill Deacon This option enables the workaround for the 720789 Cortex-A9 (prior to 783cdf357f1SWill Deacon r2p0) erratum. A faulty ASID can be sent to the other CPUs for the 784cdf357f1SWill Deacon broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS. 785cdf357f1SWill Deacon As a consequence of this erratum, some TLB entries which should be 786cdf357f1SWill Deacon invalidated are not, resulting in an incoherency in the system page 787cdf357f1SWill Deacon tables. The workaround changes the TLB flushing routines to invalidate 788cdf357f1SWill Deacon entries regardless of the ASID. 789475d92fcSWill Deacon 790475d92fcSWill Deaconconfig ARM_ERRATA_743622 791475d92fcSWill Deacon bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption" 792475d92fcSWill Deacon depends on CPU_V7 79362e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 794475d92fcSWill Deacon help 795475d92fcSWill Deacon This option enables the workaround for the 743622 Cortex-A9 796efbc74acSWill Deacon (r2p*) erratum. Under very rare conditions, a faulty 797475d92fcSWill Deacon optimisation in the Cortex-A9 Store Buffer may lead to data 798475d92fcSWill Deacon corruption. This workaround sets a specific bit in the diagnostic 799475d92fcSWill Deacon register of the Cortex-A9 which disables the Store Buffer 800475d92fcSWill Deacon optimisation, preventing the defect from occurring. This has no 801475d92fcSWill Deacon visible impact on the overall performance or power consumption of the 802475d92fcSWill Deacon processor. 803475d92fcSWill Deacon 8049a27c27cSWill Deaconconfig ARM_ERRATA_751472 8059a27c27cSWill Deacon bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation" 806ba90c516SDave Martin depends on CPU_V7 80762e4d357SRob Herring depends on !ARCH_MULTIPLATFORM 8089a27c27cSWill Deacon help 8099a27c27cSWill Deacon This option enables the workaround for the 751472 Cortex-A9 (prior 8109a27c27cSWill Deacon to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the 8119a27c27cSWill Deacon completion of a following broadcasted operation if the second 8129a27c27cSWill Deacon operation is received by a CPU before the ICIALLUIS has completed, 8139a27c27cSWill Deacon potentially leading to corrupted entries in the cache or TLB. 8149a27c27cSWill Deacon 815fcbdc5feSWill Deaconconfig ARM_ERRATA_754322 816fcbdc5feSWill Deacon bool "ARM errata: possible faulty MMU translations following an ASID switch" 817fcbdc5feSWill Deacon depends on CPU_V7 818fcbdc5feSWill Deacon help 819fcbdc5feSWill Deacon This option enables the workaround for the 754322 Cortex-A9 (r2p*, 820fcbdc5feSWill Deacon r3p*) erratum. A speculative memory access may cause a page table walk 821fcbdc5feSWill Deacon which starts prior to an ASID switch but completes afterwards. This 822fcbdc5feSWill Deacon can populate the micro-TLB with a stale entry which may be hit with 823fcbdc5feSWill Deacon the new ASID. This workaround places two dsb instructions in the mm 824fcbdc5feSWill Deacon switching code so that no page table walks can cross the ASID switch. 825fcbdc5feSWill Deacon 8265dab26afSWill Deaconconfig ARM_ERRATA_754327 8275dab26afSWill Deacon bool "ARM errata: no automatic Store Buffer drain" 8285dab26afSWill Deacon depends on CPU_V7 && SMP 8295dab26afSWill Deacon help 8305dab26afSWill Deacon This option enables the workaround for the 754327 Cortex-A9 (prior to 8315dab26afSWill Deacon r2p0) erratum. The Store Buffer does not have any automatic draining 8325dab26afSWill Deacon mechanism and therefore a livelock may occur if an external agent 8335dab26afSWill Deacon continuously polls a memory location waiting to observe an update. 8345dab26afSWill Deacon This workaround defines cpu_relax() as smp_mb(), preventing correctly 8355dab26afSWill Deacon written polling loops from denying visibility of updates to memory. 8365dab26afSWill Deacon 837145e10e1SCatalin Marinasconfig ARM_ERRATA_364296 838145e10e1SCatalin Marinas bool "ARM errata: Possible cache data corruption with hit-under-miss enabled" 839fd832478SFabio Estevam depends on CPU_V6 840145e10e1SCatalin Marinas help 841145e10e1SCatalin Marinas This options enables the workaround for the 364296 ARM1136 842145e10e1SCatalin Marinas r0p2 erratum (possible cache data corruption with 843145e10e1SCatalin Marinas hit-under-miss enabled). It sets the undocumented bit 31 in 844145e10e1SCatalin Marinas the auxiliary control register and the FI bit in the control 845145e10e1SCatalin Marinas register, thus disabling hit-under-miss without putting the 846145e10e1SCatalin Marinas processor into full low interrupt latency mode. ARM11MPCore 847145e10e1SCatalin Marinas is not affected. 848145e10e1SCatalin Marinas 849f630c1bdSWill Deaconconfig ARM_ERRATA_764369 850f630c1bdSWill Deacon bool "ARM errata: Data cache line maintenance operation by MVA may not succeed" 851f630c1bdSWill Deacon depends on CPU_V7 && SMP 852f630c1bdSWill Deacon help 853f630c1bdSWill Deacon This option enables the workaround for erratum 764369 854f630c1bdSWill Deacon affecting Cortex-A9 MPCore with two or more processors (all 855f630c1bdSWill Deacon current revisions). Under certain timing circumstances, a data 856f630c1bdSWill Deacon cache line maintenance operation by MVA targeting an Inner 857f630c1bdSWill Deacon Shareable memory region may fail to proceed up to either the 858f630c1bdSWill Deacon Point of Coherency or to the Point of Unification of the 859f630c1bdSWill Deacon system. This workaround adds a DSB instruction before the 860f630c1bdSWill Deacon relevant cache maintenance functions and sets a specific bit 861f630c1bdSWill Deacon in the diagnostic control register of the SCU. 862f630c1bdSWill Deacon 8638294fec1SNick Hawkinsconfig ARM_ERRATA_764319 8648294fec1SNick Hawkins bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction" 8658294fec1SNick Hawkins depends on CPU_V7 8668294fec1SNick Hawkins help 8678294fec1SNick Hawkins This option enables the workaround for the 764319 Cortex A-9 erratum. 8688294fec1SNick Hawkins CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an 8698294fec1SNick Hawkins unexpected Undefined Instruction exception when the DBGSWENABLE 8708294fec1SNick Hawkins external pin is set to 0, even when the CP14 accesses are performed 8718294fec1SNick Hawkins from a privileged mode. This work around catches the exception in a 8728294fec1SNick Hawkins way the kernel does not stop execution. 8738294fec1SNick Hawkins 8747253b85cSSimon Hormanconfig ARM_ERRATA_775420 8757253b85cSSimon Horman bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock" 8767253b85cSSimon Horman depends on CPU_V7 8777253b85cSSimon Horman help 8787253b85cSSimon Horman This option enables the workaround for the 775420 Cortex-A9 (r2p2, 879cb73737eSGeert Uytterhoeven r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance 8807253b85cSSimon Horman operation aborts with MMU exception, it might cause the processor 8817253b85cSSimon Horman to deadlock. This workaround puts DSB before executing ISB if 8827253b85cSSimon Horman an abort may occur on cache maintenance. 8837253b85cSSimon Horman 88493dc6887SCatalin Marinasconfig ARM_ERRATA_798181 88593dc6887SCatalin Marinas bool "ARM errata: TLBI/DSB failure on Cortex-A15" 88693dc6887SCatalin Marinas depends on CPU_V7 && SMP 88793dc6887SCatalin Marinas help 88893dc6887SCatalin Marinas On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not 88993dc6887SCatalin Marinas adequately shooting down all use of the old entries. This 89093dc6887SCatalin Marinas option enables the Linux kernel workaround for this erratum 89193dc6887SCatalin Marinas which sends an IPI to the CPUs that are running the same ASID 89293dc6887SCatalin Marinas as the one being invalidated. 89393dc6887SCatalin Marinas 89484b6504fSWill Deaconconfig ARM_ERRATA_773022 89584b6504fSWill Deacon bool "ARM errata: incorrect instructions may be executed from loop buffer" 89684b6504fSWill Deacon depends on CPU_V7 89784b6504fSWill Deacon help 89884b6504fSWill Deacon This option enables the workaround for the 773022 Cortex-A15 89984b6504fSWill Deacon (up to r0p4) erratum. In certain rare sequences of code, the 90084b6504fSWill Deacon loop buffer may deliver incorrect instructions. This 90184b6504fSWill Deacon workaround disables the loop buffer to avoid the erratum. 90284b6504fSWill Deacon 90362c0f4a5SDoug Andersonconfig ARM_ERRATA_818325_852422 90462c0f4a5SDoug Anderson bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption" 90562c0f4a5SDoug Anderson depends on CPU_V7 90662c0f4a5SDoug Anderson help 90762c0f4a5SDoug Anderson This option enables the workaround for: 90862c0f4a5SDoug Anderson - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM 90962c0f4a5SDoug Anderson instruction might deadlock. Fixed in r0p1. 91062c0f4a5SDoug Anderson - Cortex-A12 852422: Execution of a sequence of instructions might 91162c0f4a5SDoug Anderson lead to either a data corruption or a CPU deadlock. Not fixed in 91262c0f4a5SDoug Anderson any Cortex-A12 cores yet. 91362c0f4a5SDoug Anderson This workaround for all both errata involves setting bit[12] of the 91462c0f4a5SDoug Anderson Feature Register. This bit disables an optimisation applied to a 91562c0f4a5SDoug Anderson sequence of 2 instructions that use opposing condition codes. 91662c0f4a5SDoug Anderson 917416bcf21SDoug Andersonconfig ARM_ERRATA_821420 918416bcf21SDoug Anderson bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock" 919416bcf21SDoug Anderson depends on CPU_V7 920416bcf21SDoug Anderson help 921416bcf21SDoug Anderson This option enables the workaround for the 821420 Cortex-A12 922416bcf21SDoug Anderson (all revs) erratum. In very rare timing conditions, a sequence 923416bcf21SDoug Anderson of VMOV to Core registers instructions, for which the second 924416bcf21SDoug Anderson one is in the shadow of a branch or abort, can lead to a 925416bcf21SDoug Anderson deadlock when the VMOV instructions are issued out-of-order. 926416bcf21SDoug Anderson 9279f6f9354SDoug Andersonconfig ARM_ERRATA_825619 9289f6f9354SDoug Anderson bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock" 9299f6f9354SDoug Anderson depends on CPU_V7 9309f6f9354SDoug Anderson help 9319f6f9354SDoug Anderson This option enables the workaround for the 825619 Cortex-A12 9329f6f9354SDoug Anderson (all revs) erratum. Within rare timing constraints, executing a 9339f6f9354SDoug Anderson DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable 9349f6f9354SDoug Anderson and Device/Strongly-Ordered loads and stores might cause deadlock 9359f6f9354SDoug Anderson 936304009a1SDoug Andersonconfig ARM_ERRATA_857271 937304009a1SDoug Anderson bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions" 938304009a1SDoug Anderson depends on CPU_V7 939304009a1SDoug Anderson help 940304009a1SDoug Anderson This option enables the workaround for the 857271 Cortex-A12 941304009a1SDoug Anderson (all revs) erratum. Under very rare timing conditions, the CPU might 942304009a1SDoug Anderson hang. The workaround is expected to have a < 1% performance impact. 943304009a1SDoug Anderson 9449f6f9354SDoug Andersonconfig ARM_ERRATA_852421 9459f6f9354SDoug Anderson bool "ARM errata: A17: DMB ST might fail to create order between stores" 9469f6f9354SDoug Anderson depends on CPU_V7 9479f6f9354SDoug Anderson help 9489f6f9354SDoug Anderson This option enables the workaround for the 852421 Cortex-A17 9499f6f9354SDoug Anderson (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions, 9509f6f9354SDoug Anderson execution of a DMB ST instruction might fail to properly order 9519f6f9354SDoug Anderson stores from GroupA and stores from GroupB. 9529f6f9354SDoug Anderson 95362c0f4a5SDoug Andersonconfig ARM_ERRATA_852423 95462c0f4a5SDoug Anderson bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption" 95562c0f4a5SDoug Anderson depends on CPU_V7 95662c0f4a5SDoug Anderson help 95762c0f4a5SDoug Anderson This option enables the workaround for: 95862c0f4a5SDoug Anderson - Cortex-A17 852423: Execution of a sequence of instructions might 95962c0f4a5SDoug Anderson lead to either a data corruption or a CPU deadlock. Not fixed in 96062c0f4a5SDoug Anderson any Cortex-A17 cores yet. 96162c0f4a5SDoug Anderson This is identical to Cortex-A12 erratum 852422. It is a separate 96262c0f4a5SDoug Anderson config option from the A12 erratum due to the way errata are checked 96362c0f4a5SDoug Anderson for and handled. 96462c0f4a5SDoug Anderson 965304009a1SDoug Andersonconfig ARM_ERRATA_857272 966304009a1SDoug Anderson bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions" 967304009a1SDoug Anderson depends on CPU_V7 968304009a1SDoug Anderson help 969304009a1SDoug Anderson This option enables the workaround for the 857272 Cortex-A17 erratum. 970304009a1SDoug Anderson This erratum is not known to be fixed in any A17 revision. 971304009a1SDoug Anderson This is identical to Cortex-A12 erratum 857271. It is a separate 972304009a1SDoug Anderson config option from the A12 erratum due to the way errata are checked 973304009a1SDoug Anderson for and handled. 974304009a1SDoug Anderson 9751da177e4SLinus Torvaldsendmenu 9761da177e4SLinus Torvalds 9771da177e4SLinus Torvaldssource "arch/arm/common/Kconfig" 9781da177e4SLinus Torvalds 9791da177e4SLinus Torvaldsmenu "Bus support" 9801da177e4SLinus Torvalds 9811da177e4SLinus Torvaldsconfig ISA 9821da177e4SLinus Torvalds bool 9831da177e4SLinus Torvalds help 9841da177e4SLinus Torvalds Find out whether you have ISA slots on your motherboard. ISA is the 9851da177e4SLinus Torvalds name of a bus system, i.e. the way the CPU talks to the other stuff 9861da177e4SLinus Torvalds inside your box. Other bus systems are PCI, EISA, MicroChannel 9871da177e4SLinus Torvalds (MCA) or VESA. ISA is an older system, now being displaced by PCI; 9881da177e4SLinus Torvalds newer boards don't support it. If you have ISA, say Y, otherwise N. 9891da177e4SLinus Torvalds 990065909b9SRussell King# Select ISA DMA controller support 9911da177e4SLinus Torvaldsconfig ISA_DMA 9921da177e4SLinus Torvalds bool 993065909b9SRussell King select ISA_DMA_API 9941da177e4SLinus Torvalds 995065909b9SRussell King# Select ISA DMA interface 9965cae841bSAl Viroconfig ISA_DMA_API 9975cae841bSAl Viro bool 9985cae841bSAl Viro 999b080ac8aSMarcelo Roberto Jimenezconfig PCI_NANOENGINE 1000b080ac8aSMarcelo Roberto Jimenez bool "BSE nanoEngine PCI support" 1001b080ac8aSMarcelo Roberto Jimenez depends on SA1100_NANOENGINE 1002b080ac8aSMarcelo Roberto Jimenez help 1003b080ac8aSMarcelo Roberto Jimenez Enable PCI on the BSE nanoEngine board. 1004b080ac8aSMarcelo Roberto Jimenez 1005779eb41cSBenjamin Gaignardconfig ARM_ERRATA_814220 1006779eb41cSBenjamin Gaignard bool "ARM errata: Cache maintenance by set/way operations can execute out of order" 1007779eb41cSBenjamin Gaignard depends on CPU_V7 1008779eb41cSBenjamin Gaignard help 1009779eb41cSBenjamin Gaignard The v7 ARM states that all cache and branch predictor maintenance 1010779eb41cSBenjamin Gaignard operations that do not specify an address execute, relative to 1011779eb41cSBenjamin Gaignard each other, in program order. 1012779eb41cSBenjamin Gaignard However, because of this erratum, an L2 set/way cache maintenance 1013779eb41cSBenjamin Gaignard operation can overtake an L1 set/way cache maintenance operation. 1014779eb41cSBenjamin Gaignard This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3, 1015779eb41cSBenjamin Gaignard r0p4, r0p5. 1016779eb41cSBenjamin Gaignard 10171da177e4SLinus Torvaldsendmenu 10181da177e4SLinus Torvalds 10191da177e4SLinus Torvaldsmenu "Kernel Features" 10201da177e4SLinus Torvalds 10213b55658aSDave Martinconfig HAVE_SMP 10223b55658aSDave Martin bool 10233b55658aSDave Martin help 10243b55658aSDave Martin This option should be selected by machines which have an SMP- 10253b55658aSDave Martin capable CPU. 10263b55658aSDave Martin 10273b55658aSDave Martin The only effect of this option is to make the SMP-related 10283b55658aSDave Martin options available to the user for configuration. 10293b55658aSDave Martin 10301da177e4SLinus Torvaldsconfig SMP 1031bb2d8130SRussell King bool "Symmetric Multi-Processing" 1032fbb4ddacSRussell King depends on CPU_V6K || CPU_V7 10333b55658aSDave Martin depends on HAVE_SMP 1034801bb21cSJonathan Austin depends on MMU || ARM_MPU 10350361748fSArnd Bergmann select IRQ_WORK 10361da177e4SLinus Torvalds help 10371da177e4SLinus Torvalds This enables support for systems with more than one CPU. If you have 10384a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 10394a474157SRobert Graffham than one CPU, say Y. 10401da177e4SLinus Torvalds 10414a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 10421da177e4SLinus Torvalds machines, but will use only one CPU of a multiprocessor machine. If 10434a474157SRobert Graffham you say Y here, the kernel will run on many, but not all, 10444a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 10454a474157SRobert Graffham will run faster if you say N here. 10461da177e4SLinus Torvalds 1047cb1aaebeSMauro Carvalho Chehab See also <file:Documentation/x86/i386/IO-APIC.rst>, 10484f4cfa6cSMauro Carvalho Chehab <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at 104950a23e6eSJustin P. Mattock <http://tldp.org/HOWTO/SMP-HOWTO.html>. 10501da177e4SLinus Torvalds 10511da177e4SLinus Torvalds If you don't know what to do here, say N. 10521da177e4SLinus Torvalds 1053f00ec48fSRussell Kingconfig SMP_ON_UP 10545744ff43SRussell King bool "Allow booting SMP kernel on uniprocessor systems" 1055801bb21cSJonathan Austin depends on SMP && !XIP_KERNEL && MMU 1056f00ec48fSRussell King default y 1057f00ec48fSRussell King help 1058f00ec48fSRussell King SMP kernels contain instructions which fail on non-SMP processors. 1059f00ec48fSRussell King Enabling this option allows the kernel to modify itself to make 1060f00ec48fSRussell King these instructions safe. Disabling it allows about 1K of space 1061f00ec48fSRussell King savings. 1062f00ec48fSRussell King 1063f00ec48fSRussell King If you don't know what to do here, say Y. 1064f00ec48fSRussell King 106550596b75SArd Biesheuvel 106650596b75SArd Biesheuvelconfig CURRENT_POINTER_IN_TPIDRURO 106750596b75SArd Biesheuvel def_bool y 1068b87cf911SArd Biesheuvel depends on CPU_32v6K && !CPU_V6 106950596b75SArd Biesheuvel 1070d4664b6cSArd Biesheuvelconfig IRQSTACKS 1071d4664b6cSArd Biesheuvel def_bool y 10729974f857SArd Biesheuvel select HAVE_IRQ_EXIT_ON_IRQ_STACK 10739974f857SArd Biesheuvel select HAVE_SOFTIRQ_ON_OWN_STACK 10741da177e4SLinus Torvalds 1075c9018aabSVincent Guittotconfig ARM_CPU_TOPOLOGY 1076c9018aabSVincent Guittot bool "Support cpu topology definition" 1077c9018aabSVincent Guittot depends on SMP && CPU_V7 1078c9018aabSVincent Guittot default y 1079c9018aabSVincent Guittot help 1080c9018aabSVincent Guittot Support ARM cpu topology definition. The MPIDR register defines 1081c9018aabSVincent Guittot affinity between processors which is then used to describe the cpu 1082c9018aabSVincent Guittot topology of an ARM System. 1083c9018aabSVincent Guittot 1084c9018aabSVincent Guittotconfig SCHED_MC 1085c9018aabSVincent Guittot bool "Multi-core scheduler support" 1086c9018aabSVincent Guittot depends on ARM_CPU_TOPOLOGY 1087c9018aabSVincent Guittot help 1088c9018aabSVincent Guittot Multi-core scheduler support improves the CPU scheduler's decision 1089c9018aabSVincent Guittot making when dealing with multi-core CPU chips at a cost of slightly 1090c9018aabSVincent Guittot increased overhead in some places. If unsure say N here. 1091c9018aabSVincent Guittot 1092c9018aabSVincent Guittotconfig SCHED_SMT 1093c9018aabSVincent Guittot bool "SMT scheduler support" 1094c9018aabSVincent Guittot depends on ARM_CPU_TOPOLOGY 1095c9018aabSVincent Guittot help 1096c9018aabSVincent Guittot Improves the CPU scheduler's decision making when dealing with 1097c9018aabSVincent Guittot MultiThreading at a cost of slightly increased overhead in some 1098c9018aabSVincent Guittot places. If unsure say N here. 1099c9018aabSVincent Guittot 1100a8cbcd92SRussell Kingconfig HAVE_ARM_SCU 1101a8cbcd92SRussell King bool 1102a8cbcd92SRussell King help 11038f433ec4SGeert Uytterhoeven This option enables support for the ARM snoop control unit 1104a8cbcd92SRussell King 11058a4da6e3SMark Rutlandconfig HAVE_ARM_ARCH_TIMER 1106022c03a2SMarc Zyngier bool "Architected timer support" 1107022c03a2SMarc Zyngier depends on CPU_V7 11088a4da6e3SMark Rutland select ARM_ARCH_TIMER 1109022c03a2SMarc Zyngier help 1110022c03a2SMarc Zyngier This option enables support for the ARM architected timer 1111022c03a2SMarc Zyngier 1112f32f4ce2SRussell Kingconfig HAVE_ARM_TWD 1113f32f4ce2SRussell King bool 1114f32f4ce2SRussell King help 1115f32f4ce2SRussell King This options enables support for the ARM timer and watchdog unit 1116f32f4ce2SRussell King 1117e8db288eSNicolas Pitreconfig MCPM 1118e8db288eSNicolas Pitre bool "Multi-Cluster Power Management" 1119e8db288eSNicolas Pitre depends on CPU_V7 && SMP 1120e8db288eSNicolas Pitre help 1121e8db288eSNicolas Pitre This option provides the common power management infrastructure 1122e8db288eSNicolas Pitre for (multi-)cluster based systems, such as big.LITTLE based 1123e8db288eSNicolas Pitre systems. 1124e8db288eSNicolas Pitre 1125ebf4a5c5SHaojian Zhuangconfig MCPM_QUAD_CLUSTER 1126ebf4a5c5SHaojian Zhuang bool 1127ebf4a5c5SHaojian Zhuang depends on MCPM 1128ebf4a5c5SHaojian Zhuang help 1129ebf4a5c5SHaojian Zhuang To avoid wasting resources unnecessarily, MCPM only supports up 1130ebf4a5c5SHaojian Zhuang to 2 clusters by default. 1131ebf4a5c5SHaojian Zhuang Platforms with 3 or 4 clusters that use MCPM must select this 1132ebf4a5c5SHaojian Zhuang option to allow the additional clusters to be managed. 1133ebf4a5c5SHaojian Zhuang 11341c33be57SNicolas Pitreconfig BIG_LITTLE 11351c33be57SNicolas Pitre bool "big.LITTLE support (Experimental)" 11361c33be57SNicolas Pitre depends on CPU_V7 && SMP 11371c33be57SNicolas Pitre select MCPM 11381c33be57SNicolas Pitre help 11391c33be57SNicolas Pitre This option enables support selections for the big.LITTLE 11401c33be57SNicolas Pitre system architecture. 11411c33be57SNicolas Pitre 11421c33be57SNicolas Pitreconfig BL_SWITCHER 11431c33be57SNicolas Pitre bool "big.LITTLE switcher support" 11446c044fecSArnd Bergmann depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC 114551aaf81fSRussell King select CPU_PM 11461c33be57SNicolas Pitre help 11471c33be57SNicolas Pitre The big.LITTLE "switcher" provides the core functionality to 11481c33be57SNicolas Pitre transparently handle transition between a cluster of A15's 11491c33be57SNicolas Pitre and a cluster of A7's in a big.LITTLE system. 11501c33be57SNicolas Pitre 1151b22537c6SNicolas Pitreconfig BL_SWITCHER_DUMMY_IF 1152b22537c6SNicolas Pitre tristate "Simple big.LITTLE switcher user interface" 1153b22537c6SNicolas Pitre depends on BL_SWITCHER && DEBUG_KERNEL 1154b22537c6SNicolas Pitre help 1155b22537c6SNicolas Pitre This is a simple and dummy char dev interface to control 1156b22537c6SNicolas Pitre the big.LITTLE switcher core code. It is meant for 1157b22537c6SNicolas Pitre debugging purposes only. 1158b22537c6SNicolas Pitre 11598d5796d2SLennert Buytenhekchoice 11608d5796d2SLennert Buytenhek prompt "Memory split" 1161006fa259SRussell King depends on MMU 11628d5796d2SLennert Buytenhek default VMSPLIT_3G 11638d5796d2SLennert Buytenhek help 11648d5796d2SLennert Buytenhek Select the desired split between kernel and user memory. 11658d5796d2SLennert Buytenhek 11668d5796d2SLennert Buytenhek If you are not absolutely sure what you are doing, leave this 11678d5796d2SLennert Buytenhek option alone! 11688d5796d2SLennert Buytenhek 11698d5796d2SLennert Buytenhek config VMSPLIT_3G 11708d5796d2SLennert Buytenhek bool "3G/1G user/kernel split" 117163ce446cSNicolas Pitre config VMSPLIT_3G_OPT 1172bbeedfdaSYisheng Xie depends on !ARM_LPAE 117363ce446cSNicolas Pitre bool "3G/1G user/kernel split (for full 1G low memory)" 11748d5796d2SLennert Buytenhek config VMSPLIT_2G 11758d5796d2SLennert Buytenhek bool "2G/2G user/kernel split" 11768d5796d2SLennert Buytenhek config VMSPLIT_1G 11778d5796d2SLennert Buytenhek bool "1G/3G user/kernel split" 11788d5796d2SLennert Buytenhekendchoice 11798d5796d2SLennert Buytenhek 11808d5796d2SLennert Buytenhekconfig PAGE_OFFSET 11818d5796d2SLennert Buytenhek hex 1182006fa259SRussell King default PHYS_OFFSET if !MMU 11838d5796d2SLennert Buytenhek default 0x40000000 if VMSPLIT_1G 11848d5796d2SLennert Buytenhek default 0x80000000 if VMSPLIT_2G 118563ce446cSNicolas Pitre default 0xB0000000 if VMSPLIT_3G_OPT 11868d5796d2SLennert Buytenhek default 0xC0000000 11878d5796d2SLennert Buytenhek 1188c12366baSLinus Walleijconfig KASAN_SHADOW_OFFSET 1189c12366baSLinus Walleij hex 1190c12366baSLinus Walleij depends on KASAN 1191c12366baSLinus Walleij default 0x1f000000 if PAGE_OFFSET=0x40000000 1192c12366baSLinus Walleij default 0x5f000000 if PAGE_OFFSET=0x80000000 1193c12366baSLinus Walleij default 0x9f000000 if PAGE_OFFSET=0xC0000000 1194c12366baSLinus Walleij default 0x8f000000 if PAGE_OFFSET=0xB0000000 1195c12366baSLinus Walleij default 0xffffffff 1196c12366baSLinus Walleij 11971da177e4SLinus Torvaldsconfig NR_CPUS 11981da177e4SLinus Torvalds int "Maximum number of CPUs (2-32)" 1199d624833fSArd Biesheuvel range 2 16 if DEBUG_KMAP_LOCAL 1200d624833fSArd Biesheuvel range 2 32 if !DEBUG_KMAP_LOCAL 12011da177e4SLinus Torvalds depends on SMP 12021da177e4SLinus Torvalds default "4" 1203d624833fSArd Biesheuvel help 1204d624833fSArd Biesheuvel The maximum number of CPUs that the kernel can support. 1205d624833fSArd Biesheuvel Up to 32 CPUs can be supported, or up to 16 if kmap_local() 1206d624833fSArd Biesheuvel debugging is enabled, which uses half of the per-CPU fixmap 1207d624833fSArd Biesheuvel slots as guard regions. 12081da177e4SLinus Torvalds 1209a054a811SRussell Kingconfig HOTPLUG_CPU 121000b7dedeSRussell King bool "Support for hot-pluggable CPUs" 121140b31360SStephen Rothwell depends on SMP 12121b5ba350SDietmar Eggemann select GENERIC_IRQ_MIGRATION 1213a054a811SRussell King help 1214a054a811SRussell King Say Y here to experiment with turning CPUs off and on. CPUs 1215a054a811SRussell King can be controlled through /sys/devices/system/cpu. 1216a054a811SRussell King 12172bdd424fSWill Deaconconfig ARM_PSCI 12182bdd424fSWill Deacon bool "Support for the ARM Power State Coordination Interface (PSCI)" 1219e679660dSJens Wiklander depends on HAVE_ARM_SMCCC 1220be120397SMark Rutland select ARM_PSCI_FW 12212bdd424fSWill Deacon help 12222bdd424fSWill Deacon Say Y here if you want Linux to communicate with system firmware 12232bdd424fSWill Deacon implementing the PSCI specification for CPU-centric power 12242bdd424fSWill Deacon management operations described in ARM document number ARM DEN 12252bdd424fSWill Deacon 0022A ("Power State Coordination Interface System Software on 12262bdd424fSWill Deacon ARM processors"). 12272bdd424fSWill Deacon 12282a6ad871SMaxime Ripard# The GPIO number here must be sorted by descending number. In case of 12292a6ad871SMaxime Ripard# a multiplatform kernel, we just want the highest value required by the 12302a6ad871SMaxime Ripard# selected platforms. 123144986ab0SPeter De Schrijver (NVIDIA)config ARCH_NR_GPIO 123244986ab0SPeter De Schrijver (NVIDIA) int 1233910499e1SKrzysztof Kozlowski default 2048 if ARCH_INTEL_SOCFPGA 1234d9be9cebSGeert Uytterhoeven default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \ 1235a3ee4feaSTao Ren ARCH_ZYNQ || ARCH_ASPEED 1236aa42587aSTomasz Figa default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \ 1237aa42587aSTomasz Figa SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210 1238eb171a99SBoris BREZILLON default 416 if ARCH_SUNXI 123906b851e5SOlof Johansson default 392 if ARCH_U8500 124001bb914cSTony Prisk default 352 if ARCH_VT8500 12417b5da4c3SHeiko Stuebner default 288 if ARCH_ROCKCHIP 12422a6ad871SMaxime Ripard default 264 if MACH_H4700 124344986ab0SPeter De Schrijver (NVIDIA) default 0 124444986ab0SPeter De Schrijver (NVIDIA) help 124544986ab0SPeter De Schrijver (NVIDIA) Maximum number of GPIOs in the system. 124644986ab0SPeter De Schrijver (NVIDIA) 124744986ab0SPeter De Schrijver (NVIDIA) If unsure, leave the default value. 124844986ab0SPeter De Schrijver (NVIDIA) 1249c9218b16SRussell Kingconfig HZ_FIXED 1250f8065813SRussell King int 12511164f672SAlexandre Belloni default 128 if SOC_AT91RM9200 125247d84682SRussell King default 0 1253c9218b16SRussell King 1254c9218b16SRussell Kingchoice 125547d84682SRussell King depends on HZ_FIXED = 0 1256c9218b16SRussell King prompt "Timer frequency" 1257c9218b16SRussell King 1258c9218b16SRussell Kingconfig HZ_100 1259c9218b16SRussell King bool "100 Hz" 1260c9218b16SRussell King 1261c9218b16SRussell Kingconfig HZ_200 1262c9218b16SRussell King bool "200 Hz" 1263c9218b16SRussell King 1264c9218b16SRussell Kingconfig HZ_250 1265c9218b16SRussell King bool "250 Hz" 1266c9218b16SRussell King 1267c9218b16SRussell Kingconfig HZ_300 1268c9218b16SRussell King bool "300 Hz" 1269c9218b16SRussell King 1270c9218b16SRussell Kingconfig HZ_500 1271c9218b16SRussell King bool "500 Hz" 1272c9218b16SRussell King 1273c9218b16SRussell Kingconfig HZ_1000 1274c9218b16SRussell King bool "1000 Hz" 1275c9218b16SRussell King 1276c9218b16SRussell Kingendchoice 1277c9218b16SRussell King 1278c9218b16SRussell Kingconfig HZ 1279c9218b16SRussell King int 128047d84682SRussell King default HZ_FIXED if HZ_FIXED != 0 1281c9218b16SRussell King default 100 if HZ_100 1282c9218b16SRussell King default 200 if HZ_200 1283c9218b16SRussell King default 250 if HZ_250 1284c9218b16SRussell King default 300 if HZ_300 1285c9218b16SRussell King default 500 if HZ_500 1286c9218b16SRussell King default 1000 1287c9218b16SRussell King 1288c9218b16SRussell Kingconfig SCHED_HRTICK 1289c9218b16SRussell King def_bool HIGH_RES_TIMERS 1290f8065813SRussell King 129116c79651SCatalin Marinasconfig THUMB2_KERNEL 1292bc7dea00SUwe Kleine-König bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY 12934477ca45SUwe Kleine-König depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K 1294bc7dea00SUwe Kleine-König default y if CPU_THUMBONLY 129589bace65SArnd Bergmann select ARM_UNWIND 129616c79651SCatalin Marinas help 129716c79651SCatalin Marinas By enabling this option, the kernel will be compiled in 129875fea300SNicolas Pitre Thumb-2 mode. 129916c79651SCatalin Marinas 130016c79651SCatalin Marinas If unsure, say N. 130116c79651SCatalin Marinas 130242f25bddSNicolas Pitreconfig ARM_PATCH_IDIV 130342f25bddSNicolas Pitre bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()" 130442f25bddSNicolas Pitre depends on CPU_32v7 && !XIP_KERNEL 130542f25bddSNicolas Pitre default y 130642f25bddSNicolas Pitre help 130742f25bddSNicolas Pitre The ARM compiler inserts calls to __aeabi_idiv() and 130842f25bddSNicolas Pitre __aeabi_uidiv() when it needs to perform division on signed 130942f25bddSNicolas Pitre and unsigned integers. Some v7 CPUs have support for the sdiv 131042f25bddSNicolas Pitre and udiv instructions that can be used to implement those 131142f25bddSNicolas Pitre functions. 131242f25bddSNicolas Pitre 131342f25bddSNicolas Pitre Enabling this option allows the kernel to modify itself to 131442f25bddSNicolas Pitre replace the first two instructions of these library functions 131542f25bddSNicolas Pitre with the sdiv or udiv plus "bx lr" instructions when the CPU 131642f25bddSNicolas Pitre it is running on supports them. Typically this will be faster 131742f25bddSNicolas Pitre and less power intensive than running the original library 131842f25bddSNicolas Pitre code to do integer division. 131942f25bddSNicolas Pitre 1320704bdda0SNicolas Pitreconfig AEABI 1321a05b9608SNick Desaulniers bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \ 1322a05b9608SNick Desaulniers !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG 1323a05b9608SNick Desaulniers default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG 1324704bdda0SNicolas Pitre help 1325704bdda0SNicolas Pitre This option allows for the kernel to be compiled using the latest 1326704bdda0SNicolas Pitre ARM ABI (aka EABI). This is only useful if you are using a user 1327704bdda0SNicolas Pitre space environment that is also compiled with EABI. 1328704bdda0SNicolas Pitre 1329704bdda0SNicolas Pitre Since there are major incompatibilities between the legacy ABI and 1330704bdda0SNicolas Pitre EABI, especially with regard to structure member alignment, this 1331704bdda0SNicolas Pitre option also changes the kernel syscall calling convention to 1332704bdda0SNicolas Pitre disambiguate both ABIs and allow for backward compatibility support 1333704bdda0SNicolas Pitre (selected with CONFIG_OABI_COMPAT). 1334704bdda0SNicolas Pitre 1335704bdda0SNicolas Pitre To use this you need GCC version 4.0.0 or later. 1336704bdda0SNicolas Pitre 13376c90c872SNicolas Pitreconfig OABI_COMPAT 1338a73a3ff1SRussell King bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)" 1339d6f94fa0SKees Cook depends on AEABI && !THUMB2_KERNEL 13406c90c872SNicolas Pitre help 13416c90c872SNicolas Pitre This option preserves the old syscall interface along with the 13426c90c872SNicolas Pitre new (ARM EABI) one. It also provides a compatibility layer to 13436c90c872SNicolas Pitre intercept syscalls that have structure arguments which layout 13446c90c872SNicolas Pitre in memory differs between the legacy ABI and the new ARM EABI 13456c90c872SNicolas Pitre (only for non "thumb" binaries). This option adds a tiny 13466c90c872SNicolas Pitre overhead to all syscalls and produces a slightly larger kernel. 134791702175SKees Cook 134891702175SKees Cook The seccomp filter system will not be available when this is 134991702175SKees Cook selected, since there is no way yet to sensibly distinguish 135091702175SKees Cook between calling conventions during filtering. 135191702175SKees Cook 13526c90c872SNicolas Pitre If you know you'll be using only pure EABI user space then you 13536c90c872SNicolas Pitre can say N here. If this option is not selected and you attempt 13546c90c872SNicolas Pitre to execute a legacy ABI binary then the result will be 13556c90c872SNicolas Pitre UNPREDICTABLE (in fact it can be predicted that it won't work 1356b02f8467SKees Cook at all). If in doubt say N. 13576c90c872SNicolas Pitre 1358fb597f2aSGregory Fongconfig ARCH_SELECT_MEMORY_MODEL 135905944d74SRussell King bool 136005944d74SRussell King 1361fb597f2aSGregory Fongconfig ARCH_FLATMEM_ENABLE 1362fb597f2aSGregory Fong bool 1363fb597f2aSGregory Fong 136405944d74SRussell Kingconfig ARCH_SPARSEMEM_ENABLE 136505944d74SRussell King bool 1366fb597f2aSGregory Fong select SPARSEMEM_STATIC if SPARSEMEM 136707a2f737SRussell King 1368053a96caSNicolas Pitreconfig HIGHMEM 1369e8db89a2SRussell King bool "High Memory Support" 1370e8db89a2SRussell King depends on MMU 13712a15ba82SThomas Gleixner select KMAP_LOCAL 1372825c43f5SArd Biesheuvel select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY 1373053a96caSNicolas Pitre help 1374053a96caSNicolas Pitre The address space of ARM processors is only 4 Gigabytes large 1375053a96caSNicolas Pitre and it has to accommodate user address space, kernel address 1376053a96caSNicolas Pitre space as well as some memory mapped IO. That means that, if you 1377053a96caSNicolas Pitre have a large amount of physical memory and/or IO, not all of the 1378053a96caSNicolas Pitre memory can be "permanently mapped" by the kernel. The physical 1379053a96caSNicolas Pitre memory that is not permanently mapped is called "high memory". 1380053a96caSNicolas Pitre 1381053a96caSNicolas Pitre Depending on the selected kernel/user memory split, minimum 1382053a96caSNicolas Pitre vmalloc space and actual amount of RAM, you may not need this 1383053a96caSNicolas Pitre option which should result in a slightly faster kernel. 1384053a96caSNicolas Pitre 1385053a96caSNicolas Pitre If unsure, say n. 1386053a96caSNicolas Pitre 138765cec8e3SRussell Kingconfig HIGHPTE 13889a431bd5SRussell King bool "Allocate 2nd-level pagetables from highmem" if EXPERT 138965cec8e3SRussell King depends on HIGHMEM 13909a431bd5SRussell King default y 1391b4d103d1SRussell King help 1392b4d103d1SRussell King The VM uses one page of physical memory for each page table. 1393b4d103d1SRussell King For systems with a lot of processes, this can use a lot of 1394b4d103d1SRussell King precious low memory, eventually leading to low memory being 1395b4d103d1SRussell King consumed by page tables. Setting this option will allow 1396b4d103d1SRussell King user-space 2nd level page tables to reside in high memory. 139765cec8e3SRussell King 1398a5e090acSRussell Kingconfig CPU_SW_DOMAIN_PAN 1399a5e090acSRussell King bool "Enable use of CPU domains to implement privileged no-access" 1400a5e090acSRussell King depends on MMU && !ARM_LPAE 14011b8873a0SJamie Iles default y 14021b8873a0SJamie Iles help 1403a5e090acSRussell King Increase kernel security by ensuring that normal kernel accesses 1404a5e090acSRussell King are unable to access userspace addresses. This can help prevent 1405a5e090acSRussell King use-after-free bugs becoming an exploitable privilege escalation 1406a5e090acSRussell King by ensuring that magic values (such as LIST_POISON) will always 1407a5e090acSRussell King fault when dereferenced. 1408a5e090acSRussell King 1409a5e090acSRussell King CPUs with low-vector mappings use a best-efforts implementation. 1410a5e090acSRussell King Their lower 1MB needs to remain accessible for the vectors, but 1411a5e090acSRussell King the remainder of userspace will become appropriately inaccessible. 1412c80d79d7SYasunori Goto 1413c80d79d7SYasunori Gotoconfig HW_PERF_EVENTS 1414fa8ad788SMark Rutland def_bool y 1415fa8ad788SMark Rutland depends on ARM_PMU 14161b8873a0SJamie Iles 14177d485f64SArd Biesheuvelconfig ARM_MODULE_PLTS 14187d485f64SArd Biesheuvel bool "Use PLTs to allow module memory to spill over into vmalloc area" 14197d485f64SArd Biesheuvel depends on MODULES 1420e7229f7dSAnders Roxell default y 14217d485f64SArd Biesheuvel help 14227d485f64SArd Biesheuvel Allocate PLTs when loading modules so that jumps and calls whose 14237d485f64SArd Biesheuvel targets are too far away for their relative offsets to be encoded 14247d485f64SArd Biesheuvel in the instructions themselves can be bounced via veneers in the 14257d485f64SArd Biesheuvel module's PLT. This allows modules to be allocated in the generic 14267d485f64SArd Biesheuvel vmalloc area after the dedicated module memory area has been 14277d485f64SArd Biesheuvel exhausted. The modules will use slightly more memory, but after 14287d485f64SArd Biesheuvel rounding up to page size, the actual memory footprint is usually 14297d485f64SArd Biesheuvel the same. 14307d485f64SArd Biesheuvel 1431e7229f7dSAnders Roxell Disabling this is usually safe for small single-platform 1432e7229f7dSAnders Roxell configurations. If unsure, say y. 14337d485f64SArd Biesheuvel 1434c1b2d970SMagnus Dammconfig FORCE_MAX_ZONEORDER 143536d6c928SUlrich Hecht int "Maximum zone order" 1436898f08e1SYegor Yefremov default "12" if SOC_AM33XX 1437cc611137SUwe Kleine-König default "9" if SA1111 1438c1b2d970SMagnus Damm default "11" 1439c1b2d970SMagnus Damm help 1440c1b2d970SMagnus Damm The kernel memory allocator divides physically contiguous memory 1441c1b2d970SMagnus Damm blocks into "zones", where each zone is a power of two number of 1442c1b2d970SMagnus Damm pages. This option selects the largest power of two that the kernel 1443c1b2d970SMagnus Damm keeps in the memory allocator. If you need to allocate very large 1444c1b2d970SMagnus Damm blocks of physically contiguous memory, then you may need to 1445c1b2d970SMagnus Damm increase this value. 1446c1b2d970SMagnus Damm 1447c1b2d970SMagnus Damm This config option is actually maximum order plus one. For example, 1448c1b2d970SMagnus Damm a value of 11 means that the largest free memory block is 2^10 pages. 1449c1b2d970SMagnus Damm 14501da177e4SLinus Torvaldsconfig ALIGNMENT_TRAP 14513e3f354bSArnd Bergmann def_bool CPU_CP15_MMU 1452e119bfffSRussell King select HAVE_PROC_CPU if PROC_FS 14531da177e4SLinus Torvalds help 14541da177e4SLinus Torvalds ARM processors cannot fetch/store information which is not 14551da177e4SLinus Torvalds naturally aligned on the bus, i.e., a 4 byte fetch must start at an 14561da177e4SLinus Torvalds address divisible by 4. On 32-bit ARM processors, these non-aligned 14571da177e4SLinus Torvalds fetch/store instructions will be emulated in software if you say 14581da177e4SLinus Torvalds here, which has a severe performance impact. This is necessary for 14591da177e4SLinus Torvalds correct operation of some network protocols. With an IP-only 14601da177e4SLinus Torvalds configuration it is safe to say N, otherwise say Y. 14611da177e4SLinus Torvalds 146239ec58f3SLennert Buytenhekconfig UACCESS_WITH_MEMCPY 146338ef2ad5SLinus Walleij bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()" 146438ef2ad5SLinus Walleij depends on MMU 146539ec58f3SLennert Buytenhek default y if CPU_FEROCEON 146639ec58f3SLennert Buytenhek help 146739ec58f3SLennert Buytenhek Implement faster copy_to_user and clear_user methods for CPU 146839ec58f3SLennert Buytenhek cores where a 8-word STM instruction give significantly higher 146939ec58f3SLennert Buytenhek memory write throughput than a sequence of individual 32bit stores. 147039ec58f3SLennert Buytenhek 147139ec58f3SLennert Buytenhek A possible side effect is a slight increase in scheduling latency 147239ec58f3SLennert Buytenhek between threads sharing the same address space if they invoke 147339ec58f3SLennert Buytenhek such copy operations with large buffers. 147439ec58f3SLennert Buytenhek 147539ec58f3SLennert Buytenhek However, if the CPU data cache is using a write-allocate mode, 147639ec58f3SLennert Buytenhek this option is unlikely to provide any performance gain. 147739ec58f3SLennert Buytenhek 147802c2433bSStefano Stabelliniconfig PARAVIRT 147902c2433bSStefano Stabellini bool "Enable paravirtualization code" 148002c2433bSStefano Stabellini help 148102c2433bSStefano Stabellini This changes the kernel so it can modify itself when it is run 148202c2433bSStefano Stabellini under a hypervisor, potentially improving performance significantly 148302c2433bSStefano Stabellini over full virtualization. 148402c2433bSStefano Stabellini 148502c2433bSStefano Stabelliniconfig PARAVIRT_TIME_ACCOUNTING 148602c2433bSStefano Stabellini bool "Paravirtual steal time accounting" 148702c2433bSStefano Stabellini select PARAVIRT 148802c2433bSStefano Stabellini help 148902c2433bSStefano Stabellini Select this option to enable fine granularity task steal time 149002c2433bSStefano Stabellini accounting. Time spent executing other tasks in parallel with 149102c2433bSStefano Stabellini the current vCPU is discounted from the vCPU power. To account for 149202c2433bSStefano Stabellini that, there can be a small performance impact. 149302c2433bSStefano Stabellini 149402c2433bSStefano Stabellini If in doubt, say N here. 149502c2433bSStefano Stabellini 1496eff8d644SStefano Stabelliniconfig XEN_DOM0 1497eff8d644SStefano Stabellini def_bool y 1498eff8d644SStefano Stabellini depends on XEN 1499eff8d644SStefano Stabellini 1500eff8d644SStefano Stabelliniconfig XEN 1501c2ba1f7dSJulien Grall bool "Xen guest support on ARM" 150285323a99SIan Campbell depends on ARM && AEABI && OF 1503f880b67dSArnd Bergmann depends on CPU_V7 && !CPU_V6 150485323a99SIan Campbell depends on !GENERIC_ATOMIC64 15057693deccSUwe Kleine-König depends on MMU 150651aaf81fSRussell King select ARCH_DMA_ADDR_T_64BIT 150717b7ab80SStefano Stabellini select ARM_PSCI 1508f21254cdSChristoph Hellwig select SWIOTLB 150983862ccfSStefano Stabellini select SWIOTLB_XEN 151002c2433bSStefano Stabellini select PARAVIRT 1511eff8d644SStefano Stabellini help 1512eff8d644SStefano Stabellini Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. 1513eff8d644SStefano Stabellini 1514f05eb1d2SArd Biesheuvelconfig CC_HAVE_STACKPROTECTOR_TLS 1515f05eb1d2SArd Biesheuvel def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0) 1516f05eb1d2SArd Biesheuvel 1517189af465SArd Biesheuvelconfig STACKPROTECTOR_PER_TASK 1518189af465SArd Biesheuvel bool "Use a unique stack canary value for each task" 15199c46929eSArd Biesheuvel depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA 1520f05eb1d2SArd Biesheuvel depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS 1521f05eb1d2SArd Biesheuvel select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS 1522189af465SArd Biesheuvel default y 1523189af465SArd Biesheuvel help 1524189af465SArd Biesheuvel Due to the fact that GCC uses an ordinary symbol reference from 1525189af465SArd Biesheuvel which to load the value of the stack canary, this value can only 1526189af465SArd Biesheuvel change at reboot time on SMP systems, and all tasks running in the 1527189af465SArd Biesheuvel kernel's address space are forced to use the same canary value for 1528189af465SArd Biesheuvel the entire duration that the system is up. 1529189af465SArd Biesheuvel 1530189af465SArd Biesheuvel Enable this option to switch to a different method that uses a 1531189af465SArd Biesheuvel different canary value for each task. 1532189af465SArd Biesheuvel 15331da177e4SLinus Torvaldsendmenu 15341da177e4SLinus Torvalds 15351da177e4SLinus Torvaldsmenu "Boot options" 15361da177e4SLinus Torvalds 15379eb8f674SGrant Likelyconfig USE_OF 15389eb8f674SGrant Likely bool "Flattened Device Tree support" 1539b1b3f49cSRussell King select IRQ_DOMAIN 15409eb8f674SGrant Likely select OF 15419eb8f674SGrant Likely help 15429eb8f674SGrant Likely Include support for flattened device tree machine descriptions. 15439eb8f674SGrant Likely 1544bd51e2f5SNicolas Pitreconfig ATAGS 1545*96a4ce30SArnd Bergmann bool "Support for the traditional ATAGS boot data passing" 1546bd51e2f5SNicolas Pitre default y 1547bd51e2f5SNicolas Pitre help 1548bd51e2f5SNicolas Pitre This is the traditional way of passing data to the kernel at boot 1549bd51e2f5SNicolas Pitre time. If you are solely relying on the flattened device tree (or 1550bd51e2f5SNicolas Pitre the ARM_ATAG_DTB_COMPAT option) then you may unselect this option 1551bd51e2f5SNicolas Pitre to remove ATAGS support from your kernel binary. If unsure, 1552bd51e2f5SNicolas Pitre leave this to y. 1553bd51e2f5SNicolas Pitre 1554bd51e2f5SNicolas Pitreconfig DEPRECATED_PARAM_STRUCT 1555bd51e2f5SNicolas Pitre bool "Provide old way to pass kernel parameters" 1556bd51e2f5SNicolas Pitre depends on ATAGS 1557bd51e2f5SNicolas Pitre help 1558bd51e2f5SNicolas Pitre This was deprecated in 2001 and announced to live on for 5 years. 1559bd51e2f5SNicolas Pitre Some old boot loaders still use this way. 1560bd51e2f5SNicolas Pitre 15611da177e4SLinus Torvalds# Compressed boot loader in ROM. Yes, we really want to ask about 15621da177e4SLinus Torvalds# TEXT and BSS so we preserve their values in the config files. 15631da177e4SLinus Torvaldsconfig ZBOOT_ROM_TEXT 15641da177e4SLinus Torvalds hex "Compressed ROM boot loader base address" 156539c3e304SChris Packham default 0x0 15661da177e4SLinus Torvalds help 15671da177e4SLinus Torvalds The physical address at which the ROM-able zImage is to be 15681da177e4SLinus Torvalds placed in the target. Platforms which normally make use of 15691da177e4SLinus Torvalds ROM-able zImage formats normally set this to a suitable 15701da177e4SLinus Torvalds value in their defconfig file. 15711da177e4SLinus Torvalds 15721da177e4SLinus Torvalds If ZBOOT_ROM is not enabled, this has no effect. 15731da177e4SLinus Torvalds 15741da177e4SLinus Torvaldsconfig ZBOOT_ROM_BSS 15751da177e4SLinus Torvalds hex "Compressed ROM boot loader BSS address" 157639c3e304SChris Packham default 0x0 15771da177e4SLinus Torvalds help 1578f8c440b2SDan Fandrich The base address of an area of read/write memory in the target 1579f8c440b2SDan Fandrich for the ROM-able zImage which must be available while the 1580f8c440b2SDan Fandrich decompressor is running. It must be large enough to hold the 1581f8c440b2SDan Fandrich entire decompressed kernel plus an additional 128 KiB. 1582f8c440b2SDan Fandrich Platforms which normally make use of ROM-able zImage formats 1583f8c440b2SDan Fandrich normally set this to a suitable value in their defconfig file. 15841da177e4SLinus Torvalds 15851da177e4SLinus Torvalds If ZBOOT_ROM is not enabled, this has no effect. 15861da177e4SLinus Torvalds 15871da177e4SLinus Torvaldsconfig ZBOOT_ROM 15881da177e4SLinus Torvalds bool "Compressed boot loader in ROM/flash" 15891da177e4SLinus Torvalds depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS 159010968131SRussell King depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR 15911da177e4SLinus Torvalds help 15921da177e4SLinus Torvalds Say Y here if you intend to execute your compressed kernel image 15931da177e4SLinus Torvalds (zImage) directly from ROM or flash. If unsure, say N. 15941da177e4SLinus Torvalds 1595e2a6a3aaSJohn Bonesioconfig ARM_APPENDED_DTB 1596e2a6a3aaSJohn Bonesio bool "Use appended device tree blob to zImage (EXPERIMENTAL)" 159710968131SRussell King depends on OF 1598e2a6a3aaSJohn Bonesio help 1599e2a6a3aaSJohn Bonesio With this option, the boot code will look for a device tree binary 1600e2a6a3aaSJohn Bonesio (DTB) appended to zImage 1601e2a6a3aaSJohn Bonesio (e.g. cat zImage <filename>.dtb > zImage_w_dtb). 1602e2a6a3aaSJohn Bonesio 1603e2a6a3aaSJohn Bonesio This is meant as a backward compatibility convenience for those 1604e2a6a3aaSJohn Bonesio systems with a bootloader that can't be upgraded to accommodate 1605e2a6a3aaSJohn Bonesio the documented boot protocol using a device tree. 1606e2a6a3aaSJohn Bonesio 1607e2a6a3aaSJohn Bonesio Beware that there is very little in terms of protection against 1608e2a6a3aaSJohn Bonesio this option being confused by leftover garbage in memory that might 1609e2a6a3aaSJohn Bonesio look like a DTB header after a reboot if no actual DTB is appended 1610e2a6a3aaSJohn Bonesio to zImage. Do not leave this option active in a production kernel 1611e2a6a3aaSJohn Bonesio if you don't intend to always append a DTB. Proper passing of the 1612e2a6a3aaSJohn Bonesio location into r2 of a bootloader provided DTB is always preferable 1613e2a6a3aaSJohn Bonesio to this option. 1614e2a6a3aaSJohn Bonesio 1615b90b9a38SNicolas Pitreconfig ARM_ATAG_DTB_COMPAT 1616b90b9a38SNicolas Pitre bool "Supplement the appended DTB with traditional ATAG information" 1617b90b9a38SNicolas Pitre depends on ARM_APPENDED_DTB 1618b90b9a38SNicolas Pitre help 1619b90b9a38SNicolas Pitre Some old bootloaders can't be updated to a DTB capable one, yet 1620b90b9a38SNicolas Pitre they provide ATAGs with memory configuration, the ramdisk address, 1621b90b9a38SNicolas Pitre the kernel cmdline string, etc. Such information is dynamically 1622b90b9a38SNicolas Pitre provided by the bootloader and can't always be stored in a static 1623b90b9a38SNicolas Pitre DTB. To allow a device tree enabled kernel to be used with such 1624b90b9a38SNicolas Pitre bootloaders, this option allows zImage to extract the information 1625b90b9a38SNicolas Pitre from the ATAG list and store it at run time into the appended DTB. 1626b90b9a38SNicolas Pitre 1627d0f34a11SGenoud Richardchoice 1628d0f34a11SGenoud Richard prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT 1629d0f34a11SGenoud Richard default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1630d0f34a11SGenoud Richard 1631d0f34a11SGenoud Richardconfig ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1632d0f34a11SGenoud Richard bool "Use bootloader kernel arguments if available" 1633d0f34a11SGenoud Richard help 1634d0f34a11SGenoud Richard Uses the command-line options passed by the boot loader instead of 1635d0f34a11SGenoud Richard the device tree bootargs property. If the boot loader doesn't provide 1636d0f34a11SGenoud Richard any, the device tree bootargs property will be used. 1637d0f34a11SGenoud Richard 1638d0f34a11SGenoud Richardconfig ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND 1639d0f34a11SGenoud Richard bool "Extend with bootloader kernel arguments" 1640d0f34a11SGenoud Richard help 1641d0f34a11SGenoud Richard The command-line arguments provided by the boot loader will be 1642d0f34a11SGenoud Richard appended to the the device tree bootargs property. 1643d0f34a11SGenoud Richard 1644d0f34a11SGenoud Richardendchoice 1645d0f34a11SGenoud Richard 16461da177e4SLinus Torvaldsconfig CMDLINE 16471da177e4SLinus Torvalds string "Default kernel command string" 16481da177e4SLinus Torvalds default "" 16491da177e4SLinus Torvalds help 16503e3f354bSArnd Bergmann On some architectures (e.g. CATS), there is currently no way 16511da177e4SLinus Torvalds for the boot loader to pass arguments to the kernel. For these 16521da177e4SLinus Torvalds architectures, you should supply some command-line options at build 16531da177e4SLinus Torvalds time by entering them here. As a minimum, you should specify the 16541da177e4SLinus Torvalds memory size and the root device (e.g., mem=64M root=/dev/nfs). 16551da177e4SLinus Torvalds 16564394c124SVictor Boiviechoice 16574394c124SVictor Boivie prompt "Kernel command line type" if CMDLINE != "" 16584394c124SVictor Boivie default CMDLINE_FROM_BOOTLOADER 1659bd51e2f5SNicolas Pitre depends on ATAGS 16604394c124SVictor Boivie 16614394c124SVictor Boivieconfig CMDLINE_FROM_BOOTLOADER 16624394c124SVictor Boivie bool "Use bootloader kernel arguments if available" 16634394c124SVictor Boivie help 16644394c124SVictor Boivie Uses the command-line options passed by the boot loader. If 16654394c124SVictor Boivie the boot loader doesn't provide any, the default kernel command 16664394c124SVictor Boivie string provided in CMDLINE will be used. 16674394c124SVictor Boivie 16684394c124SVictor Boivieconfig CMDLINE_EXTEND 16694394c124SVictor Boivie bool "Extend bootloader kernel arguments" 16704394c124SVictor Boivie help 16714394c124SVictor Boivie The command-line arguments provided by the boot loader will be 16724394c124SVictor Boivie appended to the default kernel command string. 16734394c124SVictor Boivie 167492d2040dSAlexander Hollerconfig CMDLINE_FORCE 167592d2040dSAlexander Holler bool "Always use the default kernel command string" 167692d2040dSAlexander Holler help 167792d2040dSAlexander Holler Always use the default kernel command string, even if the boot 167892d2040dSAlexander Holler loader passes other arguments to the kernel. 167992d2040dSAlexander Holler This is useful if you cannot or don't want to change the 168092d2040dSAlexander Holler command-line options your boot loader passes to the kernel. 16814394c124SVictor Boivieendchoice 168292d2040dSAlexander Holler 16831da177e4SLinus Torvaldsconfig XIP_KERNEL 16841da177e4SLinus Torvalds bool "Kernel Execute-In-Place from ROM" 168510968131SRussell King depends on !ARM_LPAE && !ARCH_MULTIPLATFORM 16861da177e4SLinus Torvalds help 16871da177e4SLinus Torvalds Execute-In-Place allows the kernel to run from non-volatile storage 16881da177e4SLinus Torvalds directly addressable by the CPU, such as NOR flash. This saves RAM 16891da177e4SLinus Torvalds space since the text section of the kernel is not loaded from flash 16901da177e4SLinus Torvalds to RAM. Read-write sections, such as the data section and stack, 16911da177e4SLinus Torvalds are still copied to RAM. The XIP kernel is not compressed since 16921da177e4SLinus Torvalds it has to run directly from flash, so it will take more space to 16931da177e4SLinus Torvalds store it. The flash address used to link the kernel object files, 16941da177e4SLinus Torvalds and for storing it, is configuration dependent. Therefore, if you 16951da177e4SLinus Torvalds say Y here, you must know the proper physical address where to 16961da177e4SLinus Torvalds store the kernel image depending on your own flash memory usage. 16971da177e4SLinus Torvalds 16981da177e4SLinus Torvalds Also note that the make target becomes "make xipImage" rather than 16991da177e4SLinus Torvalds "make zImage" or "make Image". The final kernel binary to put in 17001da177e4SLinus Torvalds ROM memory will be arch/arm/boot/xipImage. 17011da177e4SLinus Torvalds 17021da177e4SLinus Torvalds If unsure, say N. 17031da177e4SLinus Torvalds 17041da177e4SLinus Torvaldsconfig XIP_PHYS_ADDR 17051da177e4SLinus Torvalds hex "XIP Kernel Physical Location" 17061da177e4SLinus Torvalds depends on XIP_KERNEL 17071da177e4SLinus Torvalds default "0x00080000" 17081da177e4SLinus Torvalds help 17091da177e4SLinus Torvalds This is the physical address in your flash memory the kernel will 17101da177e4SLinus Torvalds be linked for and stored to. This address is dependent on your 17111da177e4SLinus Torvalds own flash usage. 17121da177e4SLinus Torvalds 1713ca8b5d97SNicolas Pitreconfig XIP_DEFLATED_DATA 1714ca8b5d97SNicolas Pitre bool "Store kernel .data section compressed in ROM" 1715ca8b5d97SNicolas Pitre depends on XIP_KERNEL 1716ca8b5d97SNicolas Pitre select ZLIB_INFLATE 1717ca8b5d97SNicolas Pitre help 1718ca8b5d97SNicolas Pitre Before the kernel is actually executed, its .data section has to be 1719ca8b5d97SNicolas Pitre copied to RAM from ROM. This option allows for storing that data 1720ca8b5d97SNicolas Pitre in compressed form and decompressed to RAM rather than merely being 1721ca8b5d97SNicolas Pitre copied, saving some precious ROM space. A possible drawback is a 1722ca8b5d97SNicolas Pitre slightly longer boot delay. 1723ca8b5d97SNicolas Pitre 1724c587e4a6SRichard Purdieconfig KEXEC 1725c587e4a6SRichard Purdie bool "Kexec system call (EXPERIMENTAL)" 172619ab428fSStephen Warren depends on (!SMP || PM_SLEEP_SMP) 172776950f71SVincenzo Frascino depends on MMU 17282965faa5SDave Young select KEXEC_CORE 1729c587e4a6SRichard Purdie help 1730c587e4a6SRichard Purdie kexec is a system call that implements the ability to shutdown your 1731c587e4a6SRichard Purdie current kernel, and to start another kernel. It is like a reboot 173201dd2fbfSMatt LaPlante but it is independent of the system firmware. And like a reboot 1733c587e4a6SRichard Purdie you can start any kernel with it, not just Linux. 1734c587e4a6SRichard Purdie 1735c587e4a6SRichard Purdie It is an ongoing process to be certain the hardware in a machine 1736c587e4a6SRichard Purdie is properly shutdown, so do not be surprised if this code does not 1737bf220695SGeert Uytterhoeven initially work for you. 1738c587e4a6SRichard Purdie 17394cd9d6f7SRichard Purdieconfig ATAGS_PROC 17404cd9d6f7SRichard Purdie bool "Export atags in procfs" 1741bd51e2f5SNicolas Pitre depends on ATAGS && KEXEC 1742b98d7291SUli Luckas default y 17434cd9d6f7SRichard Purdie help 17444cd9d6f7SRichard Purdie Should the atags used to boot the kernel be exported in an "atags" 17454cd9d6f7SRichard Purdie file in procfs. Useful with kexec. 17464cd9d6f7SRichard Purdie 1747cb5d39b3SMika Westerbergconfig CRASH_DUMP 1748cb5d39b3SMika Westerberg bool "Build kdump crash kernel (EXPERIMENTAL)" 1749cb5d39b3SMika Westerberg help 1750cb5d39b3SMika Westerberg Generate crash dump after being started by kexec. This should 1751cb5d39b3SMika Westerberg be normally only set in special crash dump kernels which are 1752cb5d39b3SMika Westerberg loaded in the main kernel with kexec-tools into a specially 1753cb5d39b3SMika Westerberg reserved region and then later executed after a crash by 1754cb5d39b3SMika Westerberg kdump/kexec. The crash dump kernel must be compiled to a 1755cb5d39b3SMika Westerberg memory address not used by the main kernel 1756cb5d39b3SMika Westerberg 1757330d4810SMauro Carvalho Chehab For more details see Documentation/admin-guide/kdump/kdump.rst 1758cb5d39b3SMika Westerberg 1759e69edc79SEric Miaoconfig AUTO_ZRELADDR 1760e69edc79SEric Miao bool "Auto calculation of the decompressed kernel image address" 1761e69edc79SEric Miao help 1762e69edc79SEric Miao ZRELADDR is the physical address where the decompressed kernel 1763e69edc79SEric Miao image will be placed. If AUTO_ZRELADDR is selected, the address 17640673cb38SGeert Uytterhoeven will be determined at run-time, either by masking the current IP 17650673cb38SGeert Uytterhoeven with 0xf8000000, or, if invalid, from the DTB passed in r2. 17660673cb38SGeert Uytterhoeven This assumes the zImage being placed in the first 128MB from 17670673cb38SGeert Uytterhoeven start of memory. 1768e69edc79SEric Miao 176981a0bc39SRoy Franzconfig EFI_STUB 177081a0bc39SRoy Franz bool 177181a0bc39SRoy Franz 177281a0bc39SRoy Franzconfig EFI 177381a0bc39SRoy Franz bool "UEFI runtime support" 177481a0bc39SRoy Franz depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL 177581a0bc39SRoy Franz select UCS2_STRING 177681a0bc39SRoy Franz select EFI_PARAMS_FROM_FDT 177781a0bc39SRoy Franz select EFI_STUB 17782e0eb483SAtish Patra select EFI_GENERIC_STUB 177981a0bc39SRoy Franz select EFI_RUNTIME_WRAPPERS 1780a7f7f624SMasahiro Yamada help 178181a0bc39SRoy Franz This option provides support for runtime services provided 178281a0bc39SRoy Franz by UEFI firmware (such as non-volatile variables, realtime 178381a0bc39SRoy Franz clock, and platform reset). A UEFI stub is also provided to 178481a0bc39SRoy Franz allow the kernel to be booted as an EFI application. This 178581a0bc39SRoy Franz is only useful for kernels that may run on systems that have 178681a0bc39SRoy Franz UEFI firmware. 178781a0bc39SRoy Franz 1788bb817befSArd Biesheuvelconfig DMI 1789bb817befSArd Biesheuvel bool "Enable support for SMBIOS (DMI) tables" 1790bb817befSArd Biesheuvel depends on EFI 1791bb817befSArd Biesheuvel default y 1792bb817befSArd Biesheuvel help 1793bb817befSArd Biesheuvel This enables SMBIOS/DMI feature for systems. 1794bb817befSArd Biesheuvel 1795bb817befSArd Biesheuvel This option is only useful on systems that have UEFI firmware. 1796bb817befSArd Biesheuvel However, even with this option, the resultant kernel should 1797bb817befSArd Biesheuvel continue to boot on existing non-UEFI platforms. 1798bb817befSArd Biesheuvel 1799bb817befSArd Biesheuvel NOTE: This does *NOT* enable or encourage the use of DMI quirks, 1800bb817befSArd Biesheuvel i.e., the the practice of identifying the platform via DMI to 1801bb817befSArd Biesheuvel decide whether certain workarounds for buggy hardware and/or 1802bb817befSArd Biesheuvel firmware need to be enabled. This would require the DMI subsystem 1803bb817befSArd Biesheuvel to be enabled much earlier than we do on ARM, which is non-trivial. 1804bb817befSArd Biesheuvel 18051da177e4SLinus Torvaldsendmenu 18061da177e4SLinus Torvalds 1807ac9d7efcSRussell Kingmenu "CPU Power Management" 18081da177e4SLinus Torvalds 18091da177e4SLinus Torvaldssource "drivers/cpufreq/Kconfig" 18101da177e4SLinus Torvalds 1811ac9d7efcSRussell Kingsource "drivers/cpuidle/Kconfig" 1812ac9d7efcSRussell King 1813ac9d7efcSRussell Kingendmenu 1814ac9d7efcSRussell King 18151da177e4SLinus Torvaldsmenu "Floating point emulation" 18161da177e4SLinus Torvalds 18171da177e4SLinus Torvaldscomment "At least one emulation must be selected" 18181da177e4SLinus Torvalds 18191da177e4SLinus Torvaldsconfig FPE_NWFPE 18201da177e4SLinus Torvalds bool "NWFPE math emulation" 1821593c252aSDave Martin depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL 1822a7f7f624SMasahiro Yamada help 18231da177e4SLinus Torvalds Say Y to include the NWFPE floating point emulator in the kernel. 18241da177e4SLinus Torvalds This is necessary to run most binaries. Linux does not currently 18251da177e4SLinus Torvalds support floating point hardware so you need to say Y here even if 18261da177e4SLinus Torvalds your machine has an FPA or floating point co-processor podule. 18271da177e4SLinus Torvalds 18281da177e4SLinus Torvalds You may say N here if you are going to load the Acorn FPEmulator 18291da177e4SLinus Torvalds early in the bootup. 18301da177e4SLinus Torvalds 18311da177e4SLinus Torvaldsconfig FPE_NWFPE_XP 18321da177e4SLinus Torvalds bool "Support extended precision" 1833bedf142bSLennert Buytenhek depends on FPE_NWFPE 18341da177e4SLinus Torvalds help 18351da177e4SLinus Torvalds Say Y to include 80-bit support in the kernel floating-point 18361da177e4SLinus Torvalds emulator. Otherwise, only 32 and 64-bit support is compiled in. 18371da177e4SLinus Torvalds Note that gcc does not generate 80-bit operations by default, 18381da177e4SLinus Torvalds so in most cases this option only enlarges the size of the 18391da177e4SLinus Torvalds floating point emulator without any good reason. 18401da177e4SLinus Torvalds 18411da177e4SLinus Torvalds You almost surely want to say N here. 18421da177e4SLinus Torvalds 18431da177e4SLinus Torvaldsconfig FPE_FASTFPE 18441da177e4SLinus Torvalds bool "FastFPE math emulation (EXPERIMENTAL)" 1845d6f94fa0SKees Cook depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 1846a7f7f624SMasahiro Yamada help 18471da177e4SLinus Torvalds Say Y here to include the FAST floating point emulator in the kernel. 18481da177e4SLinus Torvalds This is an experimental much faster emulator which now also has full 18491da177e4SLinus Torvalds precision for the mantissa. It does not support any exceptions. 18501da177e4SLinus Torvalds It is very simple, and approximately 3-6 times faster than NWFPE. 18511da177e4SLinus Torvalds 18521da177e4SLinus Torvalds It should be sufficient for most programs. It may be not suitable 18531da177e4SLinus Torvalds for scientific calculations, but you have to check this for yourself. 18541da177e4SLinus Torvalds If you do not feel you need a faster FP emulation you should better 18551da177e4SLinus Torvalds choose NWFPE. 18561da177e4SLinus Torvalds 18571da177e4SLinus Torvaldsconfig VFP 18581da177e4SLinus Torvalds bool "VFP-format floating point maths" 1859e399b1a4SRussell King depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON 18601da177e4SLinus Torvalds help 18611da177e4SLinus Torvalds Say Y to include VFP support code in the kernel. This is needed 18621da177e4SLinus Torvalds if your hardware includes a VFP unit. 18631da177e4SLinus Torvalds 1864dc7a12bdSMauro Carvalho Chehab Please see <file:Documentation/arm/vfp/release-notes.rst> for 18651da177e4SLinus Torvalds release notes and additional status information. 18661da177e4SLinus Torvalds 18671da177e4SLinus Torvalds Say N if your target does not have VFP hardware. 18681da177e4SLinus Torvalds 186925ebee02SCatalin Marinasconfig VFPv3 187025ebee02SCatalin Marinas bool 187125ebee02SCatalin Marinas depends on VFP 187225ebee02SCatalin Marinas default y if CPU_V7 187325ebee02SCatalin Marinas 1874b5872db4SCatalin Marinasconfig NEON 1875b5872db4SCatalin Marinas bool "Advanced SIMD (NEON) Extension support" 1876b5872db4SCatalin Marinas depends on VFPv3 && CPU_V7 1877b5872db4SCatalin Marinas help 1878b5872db4SCatalin Marinas Say Y to include support code for NEON, the ARMv7 Advanced SIMD 1879b5872db4SCatalin Marinas Extension. 1880b5872db4SCatalin Marinas 188173c132c1SArd Biesheuvelconfig KERNEL_MODE_NEON 188273c132c1SArd Biesheuvel bool "Support for NEON in kernel mode" 1883c4a30c3bSRussell King depends on NEON && AEABI 188473c132c1SArd Biesheuvel help 188573c132c1SArd Biesheuvel Say Y to include support for NEON in kernel mode. 188673c132c1SArd Biesheuvel 18871da177e4SLinus Torvaldsendmenu 18881da177e4SLinus Torvalds 18891da177e4SLinus Torvaldsmenu "Power management options" 18901da177e4SLinus Torvalds 1891eceab4acSRussell Kingsource "kernel/power/Kconfig" 18921da177e4SLinus Torvalds 1893f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 189419a0519dSEzequiel Garcia depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \ 1895f0d75153SUwe Kleine-König CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK 1896f4cb5700SJohannes Berg def_bool y 1897f4cb5700SJohannes Berg 189815e0d9e3SArnd Bergmannconfig ARM_CPU_SUSPEND 18998b6f2499SLorenzo Pieralisi def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW 19001b9bdf5cSLorenzo Pieralisi depends on ARCH_SUSPEND_POSSIBLE 190115e0d9e3SArnd Bergmann 1902603fb42aSSebastian Capellaconfig ARCH_HIBERNATION_POSSIBLE 1903603fb42aSSebastian Capella bool 1904603fb42aSSebastian Capella depends on MMU 1905603fb42aSSebastian Capella default y if ARCH_SUSPEND_POSSIBLE 1906603fb42aSSebastian Capella 19071da177e4SLinus Torvaldsendmenu 19081da177e4SLinus Torvalds 1909652ccae5SArd Biesheuvelif CRYPTO 1910652ccae5SArd Biesheuvelsource "arch/arm/crypto/Kconfig" 1911652ccae5SArd Biesheuvelendif 19122cbd1cc3SStefan Agner 19132cbd1cc3SStefan Agnersource "arch/arm/Kconfig.assembler" 1914