1# SPDX-License-Identifier: GPL-2.0 2config ARM 3 bool 4 default y 5 select ARCH_32BIT_OFF_T 6 select ARCH_CLOCKSOURCE_DATA 7 select ARCH_DISCARD_MEMBLOCK if !HAVE_ARCH_PFN_VALID && !KEXEC 8 select ARCH_HAS_DEBUG_VIRTUAL if MMU 9 select ARCH_HAS_DEVMEM_IS_ALLOWED 10 select ARCH_HAS_ELF_RANDOMIZE 11 select ARCH_HAS_FORTIFY_SOURCE 12 select ARCH_HAS_KCOV 13 select ARCH_HAS_MEMBARRIER_SYNC_CORE 14 select ARCH_HAS_PTE_SPECIAL if ARM_LPAE 15 select ARCH_HAS_PHYS_TO_DMA 16 select ARCH_HAS_SETUP_DMA_OPS 17 select ARCH_HAS_SET_MEMORY 18 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 19 select ARCH_HAS_STRICT_MODULE_RWX if MMU 20 select ARCH_HAS_TEARDOWN_DMA_OPS if MMU 21 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 22 select ARCH_HAVE_CUSTOM_GPIO_H 23 select ARCH_HAS_GCOV_PROFILE_ALL 24 select ARCH_MIGHT_HAVE_PC_PARPORT 25 select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN 26 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 27 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7 28 select ARCH_SUPPORTS_ATOMIC_RMW 29 select ARCH_USE_BUILTIN_BSWAP 30 select ARCH_USE_CMPXCHG_LOCKREF 31 select ARCH_WANT_IPC_PARSE_VERSION 32 select BUILDTIME_EXTABLE_SORT if MMU 33 select CLONE_BACKWARDS 34 select CPU_PM if SUSPEND || CPU_IDLE 35 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS 36 select DMA_DECLARE_COHERENT 37 select DMA_REMAP if MMU 38 select EDAC_SUPPORT 39 select EDAC_ATOMIC_SCRUB 40 select GENERIC_ALLOCATOR 41 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY 42 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI 43 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 44 select GENERIC_CPU_AUTOPROBE 45 select GENERIC_EARLY_IOREMAP 46 select GENERIC_IDLE_POLL_SETUP 47 select GENERIC_IRQ_PROBE 48 select GENERIC_IRQ_SHOW 49 select GENERIC_IRQ_SHOW_LEVEL 50 select GENERIC_PCI_IOMAP 51 select GENERIC_SCHED_CLOCK 52 select GENERIC_SMP_IDLE_THREAD 53 select GENERIC_STRNCPY_FROM_USER 54 select GENERIC_STRNLEN_USER 55 select HANDLE_DOMAIN_IRQ 56 select HARDIRQS_SW_RESEND 57 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT 58 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 59 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU 60 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU 61 select HAVE_ARCH_MMAP_RND_BITS if MMU 62 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT 63 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 64 select HAVE_ARCH_TRACEHOOK 65 select HAVE_ARM_SMCCC if CPU_V7 66 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32 67 select HAVE_CONTEXT_TRACKING 68 select HAVE_C_RECORDMCOUNT 69 select HAVE_DEBUG_KMEMLEAK 70 select HAVE_DMA_CONTIGUOUS if MMU 71 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU 72 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 73 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU 74 select HAVE_EXIT_THREAD 75 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 76 select HAVE_FUNCTION_GRAPH_TRACER if !THUMB2_KERNEL && !CC_IS_CLANG 77 select HAVE_FUNCTION_TRACER if !XIP_KERNEL 78 select HAVE_GCC_PLUGINS 79 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7) 80 select HAVE_IDE if PCI || ISA || PCMCIA 81 select HAVE_IRQ_TIME_ACCOUNTING 82 select HAVE_KERNEL_GZIP 83 select HAVE_KERNEL_LZ4 84 select HAVE_KERNEL_LZMA 85 select HAVE_KERNEL_LZO 86 select HAVE_KERNEL_XZ 87 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M 88 select HAVE_KRETPROBES if HAVE_KPROBES 89 select HAVE_MOD_ARCH_SPECIFIC 90 select HAVE_NMI 91 select HAVE_OPROFILE if HAVE_PERF_EVENTS 92 select HAVE_OPTPROBES if !THUMB2_KERNEL 93 select HAVE_PERF_EVENTS 94 select HAVE_PERF_REGS 95 select HAVE_PERF_USER_STACK_DUMP 96 select HAVE_RCU_TABLE_FREE if SMP && ARM_LPAE 97 select HAVE_REGS_AND_STACK_ACCESS_API 98 select HAVE_RSEQ 99 select HAVE_STACKPROTECTOR 100 select HAVE_SYSCALL_TRACEPOINTS 101 select HAVE_UID16 102 select HAVE_VIRT_CPU_ACCOUNTING_GEN 103 select IRQ_FORCED_THREADING 104 select MODULES_USE_ELF_REL 105 select NEED_DMA_MAP_STATE 106 select OF_EARLY_FLATTREE if OF 107 select OLD_SIGACTION 108 select OLD_SIGSUSPEND3 109 select PCI_SYSCALL if PCI 110 select PERF_USE_VMALLOC 111 select REFCOUNT_FULL 112 select RTC_LIB 113 select SYS_SUPPORTS_APM_EMULATION 114 # Above selects are sorted alphabetically; please add new ones 115 # according to that. Thanks. 116 help 117 The ARM series is a line of low-power-consumption RISC chip designs 118 licensed by ARM Ltd and targeted at embedded applications and 119 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer 120 manufactured, but legacy ARM-based PC hardware remains popular in 121 Europe. There is an ARM Linux project with a web page at 122 <http://www.arm.linux.org.uk/>. 123 124config ARM_HAS_SG_CHAIN 125 bool 126 127config ARM_DMA_USE_IOMMU 128 bool 129 select ARM_HAS_SG_CHAIN 130 select NEED_SG_DMA_LENGTH 131 132if ARM_DMA_USE_IOMMU 133 134config ARM_DMA_IOMMU_ALIGNMENT 135 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers" 136 range 4 9 137 default 8 138 help 139 DMA mapping framework by default aligns all buffers to the smallest 140 PAGE_SIZE order which is greater than or equal to the requested buffer 141 size. This works well for buffers up to a few hundreds kilobytes, but 142 for larger buffers it just a waste of address space. Drivers which has 143 relatively small addressing window (like 64Mib) might run out of 144 virtual space with just a few allocations. 145 146 With this parameter you can specify the maximum PAGE_SIZE order for 147 DMA IOMMU buffers. Larger buffers will be aligned only to this 148 specified order. The order is expressed as a power of two multiplied 149 by the PAGE_SIZE. 150 151endif 152 153config SYS_SUPPORTS_APM_EMULATION 154 bool 155 156config HAVE_TCM 157 bool 158 select GENERIC_ALLOCATOR 159 160config HAVE_PROC_CPU 161 bool 162 163config NO_IOPORT_MAP 164 bool 165 166config SBUS 167 bool 168 169config STACKTRACE_SUPPORT 170 bool 171 default y 172 173config LOCKDEP_SUPPORT 174 bool 175 default y 176 177config TRACE_IRQFLAGS_SUPPORT 178 bool 179 default !CPU_V7M 180 181config RWSEM_XCHGADD_ALGORITHM 182 bool 183 default y 184 185config ARCH_HAS_ILOG2_U32 186 bool 187 188config ARCH_HAS_ILOG2_U64 189 bool 190 191config ARCH_HAS_BANDGAP 192 bool 193 194config FIX_EARLYCON_MEM 195 def_bool y if MMU 196 197config GENERIC_HWEIGHT 198 bool 199 default y 200 201config GENERIC_CALIBRATE_DELAY 202 bool 203 default y 204 205config ARCH_MAY_HAVE_PC_FDC 206 bool 207 208config ZONE_DMA 209 bool 210 211config ARCH_SUPPORTS_UPROBES 212 def_bool y 213 214config ARCH_HAS_DMA_SET_COHERENT_MASK 215 bool 216 217config GENERIC_ISA_DMA 218 bool 219 220config FIQ 221 bool 222 223config NEED_RET_TO_USER 224 bool 225 226config ARCH_MTD_XIP 227 bool 228 229config ARM_PATCH_PHYS_VIRT 230 bool "Patch physical to virtual translations at runtime" if EMBEDDED 231 default y 232 depends on !XIP_KERNEL && MMU 233 help 234 Patch phys-to-virt and virt-to-phys translation functions at 235 boot and module load time according to the position of the 236 kernel in system memory. 237 238 This can only be used with non-XIP MMU kernels where the base 239 of physical memory is at a 16MB boundary. 240 241 Only disable this option if you know that you do not require 242 this feature (eg, building a kernel for a single machine) and 243 you need to shrink the kernel to the minimal size. 244 245config NEED_MACH_IO_H 246 bool 247 help 248 Select this when mach/io.h is required to provide special 249 definitions for this platform. The need for mach/io.h should 250 be avoided when possible. 251 252config NEED_MACH_MEMORY_H 253 bool 254 help 255 Select this when mach/memory.h is required to provide special 256 definitions for this platform. The need for mach/memory.h should 257 be avoided when possible. 258 259config PHYS_OFFSET 260 hex "Physical address of main memory" if MMU 261 depends on !ARM_PATCH_PHYS_VIRT 262 default DRAM_BASE if !MMU 263 default 0x00000000 if ARCH_EBSA110 || \ 264 ARCH_FOOTBRIDGE || \ 265 ARCH_INTEGRATOR || \ 266 ARCH_IOP13XX || \ 267 ARCH_KS8695 || \ 268 ARCH_REALVIEW 269 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC 270 default 0x20000000 if ARCH_S5PV210 271 default 0xc0000000 if ARCH_SA1100 272 help 273 Please provide the physical address corresponding to the 274 location of main memory in your system. 275 276config GENERIC_BUG 277 def_bool y 278 depends on BUG 279 280config PGTABLE_LEVELS 281 int 282 default 3 if ARM_LPAE 283 default 2 284 285menu "System Type" 286 287config MMU 288 bool "MMU-based Paged Memory Management Support" 289 default y 290 help 291 Select if you want MMU-based virtualised addressing space 292 support by paged memory management. If unsure, say 'Y'. 293 294config ARCH_MMAP_RND_BITS_MIN 295 default 8 296 297config ARCH_MMAP_RND_BITS_MAX 298 default 14 if PAGE_OFFSET=0x40000000 299 default 15 if PAGE_OFFSET=0x80000000 300 default 16 301 302# 303# The "ARM system type" choice list is ordered alphabetically by option 304# text. Please add new entries in the option alphabetic order. 305# 306choice 307 prompt "ARM system type" 308 default ARM_SINGLE_ARMV7M if !MMU 309 default ARCH_MULTIPLATFORM if MMU 310 311config ARCH_MULTIPLATFORM 312 bool "Allow multiple platforms to be selected" 313 depends on MMU 314 select ARM_HAS_SG_CHAIN 315 select ARM_PATCH_PHYS_VIRT 316 select AUTO_ZRELADDR 317 select TIMER_OF 318 select COMMON_CLK 319 select GENERIC_CLOCKEVENTS 320 select GENERIC_IRQ_MULTI_HANDLER 321 select HAVE_PCI 322 select PCI_DOMAINS_GENERIC if PCI 323 select SPARSE_IRQ 324 select USE_OF 325 326config ARM_SINGLE_ARMV7M 327 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)" 328 depends on !MMU 329 select ARM_NVIC 330 select AUTO_ZRELADDR 331 select TIMER_OF 332 select COMMON_CLK 333 select CPU_V7M 334 select GENERIC_CLOCKEVENTS 335 select NO_IOPORT_MAP 336 select SPARSE_IRQ 337 select USE_OF 338 339config ARCH_EBSA110 340 bool "EBSA-110" 341 select ARCH_USES_GETTIMEOFFSET 342 select CPU_SA110 343 select ISA 344 select NEED_MACH_IO_H 345 select NEED_MACH_MEMORY_H 346 select NO_IOPORT_MAP 347 help 348 This is an evaluation board for the StrongARM processor available 349 from Digital. It has limited hardware on-board, including an 350 Ethernet interface, two PCMCIA sockets, two serial ports and a 351 parallel port. 352 353config ARCH_EP93XX 354 bool "EP93xx-based" 355 select ARCH_SPARSEMEM_ENABLE 356 select ARM_AMBA 357 imply ARM_PATCH_PHYS_VIRT 358 select ARM_VIC 359 select AUTO_ZRELADDR 360 select CLKDEV_LOOKUP 361 select CLKSRC_MMIO 362 select CPU_ARM920T 363 select GENERIC_CLOCKEVENTS 364 select GPIOLIB 365 help 366 This enables support for the Cirrus EP93xx series of CPUs. 367 368config ARCH_FOOTBRIDGE 369 bool "FootBridge" 370 select CPU_SA110 371 select FOOTBRIDGE 372 select GENERIC_CLOCKEVENTS 373 select HAVE_IDE 374 select NEED_MACH_IO_H if !MMU 375 select NEED_MACH_MEMORY_H 376 help 377 Support for systems based on the DC21285 companion chip 378 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder. 379 380config ARCH_NETX 381 bool "Hilscher NetX based" 382 select ARM_VIC 383 select CLKSRC_MMIO 384 select CPU_ARM926T 385 select GENERIC_CLOCKEVENTS 386 help 387 This enables support for systems based on the Hilscher NetX Soc 388 389config ARCH_IOP13XX 390 bool "IOP13xx-based" 391 depends on MMU 392 select CPU_XSC3 393 select NEED_MACH_MEMORY_H 394 select NEED_RET_TO_USER 395 select FORCE_PCI 396 select PLAT_IOP 397 select VMSPLIT_1G 398 select SPARSE_IRQ 399 help 400 Support for Intel's IOP13XX (XScale) family of processors. 401 402config ARCH_IOP32X 403 bool "IOP32x-based" 404 depends on MMU 405 select CPU_XSCALE 406 select GPIO_IOP 407 select GPIOLIB 408 select NEED_RET_TO_USER 409 select FORCE_PCI 410 select PLAT_IOP 411 help 412 Support for Intel's 80219 and IOP32X (XScale) family of 413 processors. 414 415config ARCH_IOP33X 416 bool "IOP33x-based" 417 depends on MMU 418 select CPU_XSCALE 419 select GPIO_IOP 420 select GPIOLIB 421 select NEED_RET_TO_USER 422 select FORCE_PCI 423 select PLAT_IOP 424 help 425 Support for Intel's IOP33X (XScale) family of processors. 426 427config ARCH_IXP4XX 428 bool "IXP4xx-based" 429 depends on MMU 430 select ARCH_HAS_DMA_SET_COHERENT_MASK 431 select ARCH_SUPPORTS_BIG_ENDIAN 432 select CLKSRC_MMIO 433 select CPU_XSCALE 434 select DMABOUNCE if PCI 435 select GENERIC_CLOCKEVENTS 436 select GPIOLIB 437 select HAVE_PCI 438 select NEED_MACH_IO_H 439 select USB_EHCI_BIG_ENDIAN_DESC 440 select USB_EHCI_BIG_ENDIAN_MMIO 441 help 442 Support for Intel's IXP4XX (XScale) family of processors. 443 444config ARCH_DOVE 445 bool "Marvell Dove" 446 select CPU_PJ4 447 select GENERIC_CLOCKEVENTS 448 select GENERIC_IRQ_MULTI_HANDLER 449 select GPIOLIB 450 select HAVE_PCI 451 select MVEBU_MBUS 452 select PINCTRL 453 select PINCTRL_DOVE 454 select PLAT_ORION_LEGACY 455 select SPARSE_IRQ 456 select PM_GENERIC_DOMAINS if PM 457 help 458 Support for the Marvell Dove SoC 88AP510 459 460config ARCH_KS8695 461 bool "Micrel/Kendin KS8695" 462 select CLKSRC_MMIO 463 select CPU_ARM922T 464 select GENERIC_CLOCKEVENTS 465 select GPIOLIB 466 select NEED_MACH_MEMORY_H 467 help 468 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based 469 System-on-Chip devices. 470 471config ARCH_W90X900 472 bool "Nuvoton W90X900 CPU" 473 select CLKDEV_LOOKUP 474 select CLKSRC_MMIO 475 select CPU_ARM926T 476 select GENERIC_CLOCKEVENTS 477 select GPIOLIB 478 help 479 Support for Nuvoton (Winbond logic dept.) ARM9 processor, 480 At present, the w90x900 has been renamed nuc900, regarding 481 the ARM series product line, you can login the following 482 link address to know more. 483 484 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/ 485 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller> 486 487config ARCH_LPC32XX 488 bool "NXP LPC32XX" 489 select ARM_AMBA 490 select CLKDEV_LOOKUP 491 select CLKSRC_LPC32XX 492 select COMMON_CLK 493 select CPU_ARM926T 494 select GENERIC_CLOCKEVENTS 495 select GENERIC_IRQ_MULTI_HANDLER 496 select GPIOLIB 497 select SPARSE_IRQ 498 select USE_OF 499 help 500 Support for the NXP LPC32XX family of processors 501 502config ARCH_PXA 503 bool "PXA2xx/PXA3xx-based" 504 depends on MMU 505 select ARCH_MTD_XIP 506 select ARM_CPU_SUSPEND if PM 507 select AUTO_ZRELADDR 508 select COMMON_CLK 509 select CLKDEV_LOOKUP 510 select CLKSRC_PXA 511 select CLKSRC_MMIO 512 select TIMER_OF 513 select CPU_XSCALE if !CPU_XSC3 514 select GENERIC_CLOCKEVENTS 515 select GENERIC_IRQ_MULTI_HANDLER 516 select GPIO_PXA 517 select GPIOLIB 518 select HAVE_IDE 519 select IRQ_DOMAIN 520 select PLAT_PXA 521 select SPARSE_IRQ 522 help 523 Support for Intel/Marvell's PXA2xx/PXA3xx processor line. 524 525config ARCH_RPC 526 bool "RiscPC" 527 depends on MMU 528 select ARCH_ACORN 529 select ARCH_MAY_HAVE_PC_FDC 530 select ARCH_SPARSEMEM_ENABLE 531 select ARCH_USES_GETTIMEOFFSET 532 select CPU_SA110 533 select FIQ 534 select HAVE_IDE 535 select HAVE_PATA_PLATFORM 536 select ISA_DMA_API 537 select NEED_MACH_IO_H 538 select NEED_MACH_MEMORY_H 539 select NO_IOPORT_MAP 540 help 541 On the Acorn Risc-PC, Linux can support the internal IDE disk and 542 CD-ROM interface, serial and parallel port, and the floppy drive. 543 544config ARCH_SA1100 545 bool "SA1100-based" 546 select ARCH_MTD_XIP 547 select ARCH_SPARSEMEM_ENABLE 548 select CLKDEV_LOOKUP 549 select CLKSRC_MMIO 550 select CLKSRC_PXA 551 select TIMER_OF if OF 552 select CPU_FREQ 553 select CPU_SA1100 554 select GENERIC_CLOCKEVENTS 555 select GENERIC_IRQ_MULTI_HANDLER 556 select GPIOLIB 557 select HAVE_IDE 558 select IRQ_DOMAIN 559 select ISA 560 select NEED_MACH_MEMORY_H 561 select SPARSE_IRQ 562 help 563 Support for StrongARM 11x0 based boards. 564 565config ARCH_S3C24XX 566 bool "Samsung S3C24XX SoCs" 567 select ATAGS 568 select CLKDEV_LOOKUP 569 select CLKSRC_SAMSUNG_PWM 570 select GENERIC_CLOCKEVENTS 571 select GPIO_SAMSUNG 572 select GPIOLIB 573 select GENERIC_IRQ_MULTI_HANDLER 574 select HAVE_S3C2410_I2C if I2C 575 select HAVE_S3C2410_WATCHDOG if WATCHDOG 576 select HAVE_S3C_RTC if RTC_CLASS 577 select NEED_MACH_IO_H 578 select SAMSUNG_ATAGS 579 select USE_OF 580 help 581 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443 582 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST 583 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the 584 Samsung SMDK2410 development board (and derivatives). 585 586config ARCH_DAVINCI 587 bool "TI DaVinci" 588 select ARCH_HAS_HOLES_MEMORYMODEL 589 select COMMON_CLK 590 select CPU_ARM926T 591 select GENERIC_ALLOCATOR 592 select GENERIC_CLOCKEVENTS 593 select GENERIC_IRQ_CHIP 594 select GENERIC_IRQ_MULTI_HANDLER 595 select GPIOLIB 596 select HAVE_IDE 597 select PM_GENERIC_DOMAINS if PM 598 select PM_GENERIC_DOMAINS_OF if PM && OF 599 select REGMAP_MMIO 600 select RESET_CONTROLLER 601 select SPARSE_IRQ 602 select USE_OF 603 select ZONE_DMA 604 help 605 Support for TI's DaVinci platform. 606 607config ARCH_OMAP1 608 bool "TI OMAP1" 609 depends on MMU 610 select ARCH_HAS_HOLES_MEMORYMODEL 611 select ARCH_OMAP 612 select CLKDEV_LOOKUP 613 select CLKSRC_MMIO 614 select GENERIC_CLOCKEVENTS 615 select GENERIC_IRQ_CHIP 616 select GENERIC_IRQ_MULTI_HANDLER 617 select GPIOLIB 618 select HAVE_IDE 619 select IRQ_DOMAIN 620 select NEED_MACH_IO_H if PCCARD 621 select NEED_MACH_MEMORY_H 622 select SPARSE_IRQ 623 help 624 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx) 625 626endchoice 627 628menu "Multiple platform selection" 629 depends on ARCH_MULTIPLATFORM 630 631comment "CPU Core family selection" 632 633config ARCH_MULTI_V4 634 bool "ARMv4 based platforms (FA526)" 635 depends on !ARCH_MULTI_V6_V7 636 select ARCH_MULTI_V4_V5 637 select CPU_FA526 638 639config ARCH_MULTI_V4T 640 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)" 641 depends on !ARCH_MULTI_V6_V7 642 select ARCH_MULTI_V4_V5 643 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \ 644 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \ 645 CPU_ARM925T || CPU_ARM940T) 646 647config ARCH_MULTI_V5 648 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)" 649 depends on !ARCH_MULTI_V6_V7 650 select ARCH_MULTI_V4_V5 651 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \ 652 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \ 653 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON) 654 655config ARCH_MULTI_V4_V5 656 bool 657 658config ARCH_MULTI_V6 659 bool "ARMv6 based platforms (ARM11)" 660 select ARCH_MULTI_V6_V7 661 select CPU_V6K 662 663config ARCH_MULTI_V7 664 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)" 665 default y 666 select ARCH_MULTI_V6_V7 667 select CPU_V7 668 select HAVE_SMP 669 670config ARCH_MULTI_V6_V7 671 bool 672 select MIGHT_HAVE_CACHE_L2X0 673 674config ARCH_MULTI_CPU_AUTO 675 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7) 676 select ARCH_MULTI_V5 677 678endmenu 679 680config ARCH_VIRT 681 bool "Dummy Virtual Machine" 682 depends on ARCH_MULTI_V7 683 select ARM_AMBA 684 select ARM_GIC 685 select ARM_GIC_V2M if PCI 686 select ARM_GIC_V3 687 select ARM_GIC_V3_ITS if PCI 688 select ARM_PSCI 689 select HAVE_ARM_ARCH_TIMER 690 select ARCH_SUPPORTS_BIG_ENDIAN 691 692# 693# This is sorted alphabetically by mach-* pathname. However, plat-* 694# Kconfigs may be included either alphabetically (according to the 695# plat- suffix) or along side the corresponding mach-* source. 696# 697source "arch/arm/mach-actions/Kconfig" 698 699source "arch/arm/mach-alpine/Kconfig" 700 701source "arch/arm/mach-artpec/Kconfig" 702 703source "arch/arm/mach-asm9260/Kconfig" 704 705source "arch/arm/mach-aspeed/Kconfig" 706 707source "arch/arm/mach-at91/Kconfig" 708 709source "arch/arm/mach-axxia/Kconfig" 710 711source "arch/arm/mach-bcm/Kconfig" 712 713source "arch/arm/mach-berlin/Kconfig" 714 715source "arch/arm/mach-clps711x/Kconfig" 716 717source "arch/arm/mach-cns3xxx/Kconfig" 718 719source "arch/arm/mach-davinci/Kconfig" 720 721source "arch/arm/mach-digicolor/Kconfig" 722 723source "arch/arm/mach-dove/Kconfig" 724 725source "arch/arm/mach-ep93xx/Kconfig" 726 727source "arch/arm/mach-exynos/Kconfig" 728source "arch/arm/plat-samsung/Kconfig" 729 730source "arch/arm/mach-footbridge/Kconfig" 731 732source "arch/arm/mach-gemini/Kconfig" 733 734source "arch/arm/mach-highbank/Kconfig" 735 736source "arch/arm/mach-hisi/Kconfig" 737 738source "arch/arm/mach-imx/Kconfig" 739 740source "arch/arm/mach-integrator/Kconfig" 741 742source "arch/arm/mach-iop13xx/Kconfig" 743 744source "arch/arm/mach-iop32x/Kconfig" 745 746source "arch/arm/mach-iop33x/Kconfig" 747 748source "arch/arm/mach-ixp4xx/Kconfig" 749 750source "arch/arm/mach-keystone/Kconfig" 751 752source "arch/arm/mach-ks8695/Kconfig" 753 754source "arch/arm/mach-mediatek/Kconfig" 755 756source "arch/arm/mach-meson/Kconfig" 757 758source "arch/arm/mach-milbeaut/Kconfig" 759 760source "arch/arm/mach-mmp/Kconfig" 761 762source "arch/arm/mach-moxart/Kconfig" 763 764source "arch/arm/mach-mv78xx0/Kconfig" 765 766source "arch/arm/mach-mvebu/Kconfig" 767 768source "arch/arm/mach-mxs/Kconfig" 769 770source "arch/arm/mach-netx/Kconfig" 771 772source "arch/arm/mach-nomadik/Kconfig" 773 774source "arch/arm/mach-npcm/Kconfig" 775 776source "arch/arm/mach-nspire/Kconfig" 777 778source "arch/arm/plat-omap/Kconfig" 779 780source "arch/arm/mach-omap1/Kconfig" 781 782source "arch/arm/mach-omap2/Kconfig" 783 784source "arch/arm/mach-orion5x/Kconfig" 785 786source "arch/arm/mach-oxnas/Kconfig" 787 788source "arch/arm/mach-picoxcell/Kconfig" 789 790source "arch/arm/mach-prima2/Kconfig" 791 792source "arch/arm/mach-pxa/Kconfig" 793source "arch/arm/plat-pxa/Kconfig" 794 795source "arch/arm/mach-qcom/Kconfig" 796 797source "arch/arm/mach-rda/Kconfig" 798 799source "arch/arm/mach-realview/Kconfig" 800 801source "arch/arm/mach-rockchip/Kconfig" 802 803source "arch/arm/mach-s3c24xx/Kconfig" 804 805source "arch/arm/mach-s3c64xx/Kconfig" 806 807source "arch/arm/mach-s5pv210/Kconfig" 808 809source "arch/arm/mach-sa1100/Kconfig" 810 811source "arch/arm/mach-shmobile/Kconfig" 812 813source "arch/arm/mach-socfpga/Kconfig" 814 815source "arch/arm/mach-spear/Kconfig" 816 817source "arch/arm/mach-sti/Kconfig" 818 819source "arch/arm/mach-stm32/Kconfig" 820 821source "arch/arm/mach-sunxi/Kconfig" 822 823source "arch/arm/mach-tango/Kconfig" 824 825source "arch/arm/mach-tegra/Kconfig" 826 827source "arch/arm/mach-u300/Kconfig" 828 829source "arch/arm/mach-uniphier/Kconfig" 830 831source "arch/arm/mach-ux500/Kconfig" 832 833source "arch/arm/mach-versatile/Kconfig" 834 835source "arch/arm/mach-vexpress/Kconfig" 836source "arch/arm/plat-versatile/Kconfig" 837 838source "arch/arm/mach-vt8500/Kconfig" 839 840source "arch/arm/mach-w90x900/Kconfig" 841 842source "arch/arm/mach-zx/Kconfig" 843 844source "arch/arm/mach-zynq/Kconfig" 845 846# ARMv7-M architecture 847config ARCH_EFM32 848 bool "Energy Micro efm32" 849 depends on ARM_SINGLE_ARMV7M 850 select GPIOLIB 851 help 852 Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko 853 processors. 854 855config ARCH_LPC18XX 856 bool "NXP LPC18xx/LPC43xx" 857 depends on ARM_SINGLE_ARMV7M 858 select ARCH_HAS_RESET_CONTROLLER 859 select ARM_AMBA 860 select CLKSRC_LPC32XX 861 select PINCTRL 862 help 863 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4 864 high performance microcontrollers. 865 866config ARCH_MPS2 867 bool "ARM MPS2 platform" 868 depends on ARM_SINGLE_ARMV7M 869 select ARM_AMBA 870 select CLKSRC_MPS2 871 help 872 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes 873 with a range of available cores like Cortex-M3/M4/M7. 874 875 Please, note that depends which Application Note is used memory map 876 for the platform may vary, so adjustment of RAM base might be needed. 877 878# Definitions to make life easier 879config ARCH_ACORN 880 bool 881 882config PLAT_IOP 883 bool 884 select GENERIC_CLOCKEVENTS 885 886config PLAT_ORION 887 bool 888 select CLKSRC_MMIO 889 select COMMON_CLK 890 select GENERIC_IRQ_CHIP 891 select IRQ_DOMAIN 892 893config PLAT_ORION_LEGACY 894 bool 895 select PLAT_ORION 896 897config PLAT_PXA 898 bool 899 900config PLAT_VERSATILE 901 bool 902 903source "arch/arm/firmware/Kconfig" 904 905source "arch/arm/mm/Kconfig" 906 907config IWMMXT 908 bool "Enable iWMMXt support" 909 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B 910 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B 911 help 912 Enable support for iWMMXt context switching at run time if 913 running on a CPU that supports it. 914 915if !MMU 916source "arch/arm/Kconfig-nommu" 917endif 918 919config PJ4B_ERRATA_4742 920 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation" 921 depends on CPU_PJ4B && MACH_ARMADA_370 922 default y 923 help 924 When coming out of either a Wait for Interrupt (WFI) or a Wait for 925 Event (WFE) IDLE states, a specific timing sensitivity exists between 926 the retiring WFI/WFE instructions and the newly issued subsequent 927 instructions. This sensitivity can result in a CPU hang scenario. 928 Workaround: 929 The software must insert either a Data Synchronization Barrier (DSB) 930 or Data Memory Barrier (DMB) command immediately after the WFI/WFE 931 instruction 932 933config ARM_ERRATA_326103 934 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory" 935 depends on CPU_V6 936 help 937 Executing a SWP instruction to read-only memory does not set bit 11 938 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to 939 treat the access as a read, preventing a COW from occurring and 940 causing the faulting task to livelock. 941 942config ARM_ERRATA_411920 943 bool "ARM errata: Invalidation of the Instruction Cache operation can fail" 944 depends on CPU_V6 || CPU_V6K 945 help 946 Invalidation of the Instruction Cache operation can 947 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176. 948 It does not affect the MPCore. This option enables the ARM Ltd. 949 recommended workaround. 950 951config ARM_ERRATA_430973 952 bool "ARM errata: Stale prediction on replaced interworking branch" 953 depends on CPU_V7 954 help 955 This option enables the workaround for the 430973 Cortex-A8 956 r1p* erratum. If a code sequence containing an ARM/Thumb 957 interworking branch is replaced with another code sequence at the 958 same virtual address, whether due to self-modifying code or virtual 959 to physical address re-mapping, Cortex-A8 does not recover from the 960 stale interworking branch prediction. This results in Cortex-A8 961 executing the new code sequence in the incorrect ARM or Thumb state. 962 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE 963 and also flushes the branch target cache at every context switch. 964 Note that setting specific bits in the ACTLR register may not be 965 available in non-secure mode. 966 967config ARM_ERRATA_458693 968 bool "ARM errata: Processor deadlock when a false hazard is created" 969 depends on CPU_V7 970 depends on !ARCH_MULTIPLATFORM 971 help 972 This option enables the workaround for the 458693 Cortex-A8 (r2p0) 973 erratum. For very specific sequences of memory operations, it is 974 possible for a hazard condition intended for a cache line to instead 975 be incorrectly associated with a different cache line. This false 976 hazard might then cause a processor deadlock. The workaround enables 977 the L1 caching of the NEON accesses and disables the PLD instruction 978 in the ACTLR register. Note that setting specific bits in the ACTLR 979 register may not be available in non-secure mode. 980 981config ARM_ERRATA_460075 982 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data" 983 depends on CPU_V7 984 depends on !ARCH_MULTIPLATFORM 985 help 986 This option enables the workaround for the 460075 Cortex-A8 (r2p0) 987 erratum. Any asynchronous access to the L2 cache may encounter a 988 situation in which recent store transactions to the L2 cache are lost 989 and overwritten with stale memory contents from external memory. The 990 workaround disables the write-allocate mode for the L2 cache via the 991 ACTLR register. Note that setting specific bits in the ACTLR register 992 may not be available in non-secure mode. 993 994config ARM_ERRATA_742230 995 bool "ARM errata: DMB operation may be faulty" 996 depends on CPU_V7 && SMP 997 depends on !ARCH_MULTIPLATFORM 998 help 999 This option enables the workaround for the 742230 Cortex-A9 1000 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction 1001 between two write operations may not ensure the correct visibility 1002 ordering of the two writes. This workaround sets a specific bit in 1003 the diagnostic register of the Cortex-A9 which causes the DMB 1004 instruction to behave as a DSB, ensuring the correct behaviour of 1005 the two writes. 1006 1007config ARM_ERRATA_742231 1008 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption" 1009 depends on CPU_V7 && SMP 1010 depends on !ARCH_MULTIPLATFORM 1011 help 1012 This option enables the workaround for the 742231 Cortex-A9 1013 (r2p0..r2p2) erratum. Under certain conditions, specific to the 1014 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode, 1015 accessing some data located in the same cache line, may get corrupted 1016 data due to bad handling of the address hazard when the line gets 1017 replaced from one of the CPUs at the same time as another CPU is 1018 accessing it. This workaround sets specific bits in the diagnostic 1019 register of the Cortex-A9 which reduces the linefill issuing 1020 capabilities of the processor. 1021 1022config ARM_ERRATA_643719 1023 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect" 1024 depends on CPU_V7 && SMP 1025 default y 1026 help 1027 This option enables the workaround for the 643719 Cortex-A9 (prior to 1028 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR 1029 register returns zero when it should return one. The workaround 1030 corrects this value, ensuring cache maintenance operations which use 1031 it behave as intended and avoiding data corruption. 1032 1033config ARM_ERRATA_720789 1034 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID" 1035 depends on CPU_V7 1036 help 1037 This option enables the workaround for the 720789 Cortex-A9 (prior to 1038 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the 1039 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS. 1040 As a consequence of this erratum, some TLB entries which should be 1041 invalidated are not, resulting in an incoherency in the system page 1042 tables. The workaround changes the TLB flushing routines to invalidate 1043 entries regardless of the ASID. 1044 1045config ARM_ERRATA_743622 1046 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption" 1047 depends on CPU_V7 1048 depends on !ARCH_MULTIPLATFORM 1049 help 1050 This option enables the workaround for the 743622 Cortex-A9 1051 (r2p*) erratum. Under very rare conditions, a faulty 1052 optimisation in the Cortex-A9 Store Buffer may lead to data 1053 corruption. This workaround sets a specific bit in the diagnostic 1054 register of the Cortex-A9 which disables the Store Buffer 1055 optimisation, preventing the defect from occurring. This has no 1056 visible impact on the overall performance or power consumption of the 1057 processor. 1058 1059config ARM_ERRATA_751472 1060 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation" 1061 depends on CPU_V7 1062 depends on !ARCH_MULTIPLATFORM 1063 help 1064 This option enables the workaround for the 751472 Cortex-A9 (prior 1065 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the 1066 completion of a following broadcasted operation if the second 1067 operation is received by a CPU before the ICIALLUIS has completed, 1068 potentially leading to corrupted entries in the cache or TLB. 1069 1070config ARM_ERRATA_754322 1071 bool "ARM errata: possible faulty MMU translations following an ASID switch" 1072 depends on CPU_V7 1073 help 1074 This option enables the workaround for the 754322 Cortex-A9 (r2p*, 1075 r3p*) erratum. A speculative memory access may cause a page table walk 1076 which starts prior to an ASID switch but completes afterwards. This 1077 can populate the micro-TLB with a stale entry which may be hit with 1078 the new ASID. This workaround places two dsb instructions in the mm 1079 switching code so that no page table walks can cross the ASID switch. 1080 1081config ARM_ERRATA_754327 1082 bool "ARM errata: no automatic Store Buffer drain" 1083 depends on CPU_V7 && SMP 1084 help 1085 This option enables the workaround for the 754327 Cortex-A9 (prior to 1086 r2p0) erratum. The Store Buffer does not have any automatic draining 1087 mechanism and therefore a livelock may occur if an external agent 1088 continuously polls a memory location waiting to observe an update. 1089 This workaround defines cpu_relax() as smp_mb(), preventing correctly 1090 written polling loops from denying visibility of updates to memory. 1091 1092config ARM_ERRATA_364296 1093 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled" 1094 depends on CPU_V6 1095 help 1096 This options enables the workaround for the 364296 ARM1136 1097 r0p2 erratum (possible cache data corruption with 1098 hit-under-miss enabled). It sets the undocumented bit 31 in 1099 the auxiliary control register and the FI bit in the control 1100 register, thus disabling hit-under-miss without putting the 1101 processor into full low interrupt latency mode. ARM11MPCore 1102 is not affected. 1103 1104config ARM_ERRATA_764369 1105 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed" 1106 depends on CPU_V7 && SMP 1107 help 1108 This option enables the workaround for erratum 764369 1109 affecting Cortex-A9 MPCore with two or more processors (all 1110 current revisions). Under certain timing circumstances, a data 1111 cache line maintenance operation by MVA targeting an Inner 1112 Shareable memory region may fail to proceed up to either the 1113 Point of Coherency or to the Point of Unification of the 1114 system. This workaround adds a DSB instruction before the 1115 relevant cache maintenance functions and sets a specific bit 1116 in the diagnostic control register of the SCU. 1117 1118config ARM_ERRATA_775420 1119 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock" 1120 depends on CPU_V7 1121 help 1122 This option enables the workaround for the 775420 Cortex-A9 (r2p2, 1123 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance 1124 operation aborts with MMU exception, it might cause the processor 1125 to deadlock. This workaround puts DSB before executing ISB if 1126 an abort may occur on cache maintenance. 1127 1128config ARM_ERRATA_798181 1129 bool "ARM errata: TLBI/DSB failure on Cortex-A15" 1130 depends on CPU_V7 && SMP 1131 help 1132 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not 1133 adequately shooting down all use of the old entries. This 1134 option enables the Linux kernel workaround for this erratum 1135 which sends an IPI to the CPUs that are running the same ASID 1136 as the one being invalidated. 1137 1138config ARM_ERRATA_773022 1139 bool "ARM errata: incorrect instructions may be executed from loop buffer" 1140 depends on CPU_V7 1141 help 1142 This option enables the workaround for the 773022 Cortex-A15 1143 (up to r0p4) erratum. In certain rare sequences of code, the 1144 loop buffer may deliver incorrect instructions. This 1145 workaround disables the loop buffer to avoid the erratum. 1146 1147config ARM_ERRATA_818325_852422 1148 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption" 1149 depends on CPU_V7 1150 help 1151 This option enables the workaround for: 1152 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM 1153 instruction might deadlock. Fixed in r0p1. 1154 - Cortex-A12 852422: Execution of a sequence of instructions might 1155 lead to either a data corruption or a CPU deadlock. Not fixed in 1156 any Cortex-A12 cores yet. 1157 This workaround for all both errata involves setting bit[12] of the 1158 Feature Register. This bit disables an optimisation applied to a 1159 sequence of 2 instructions that use opposing condition codes. 1160 1161config ARM_ERRATA_821420 1162 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock" 1163 depends on CPU_V7 1164 help 1165 This option enables the workaround for the 821420 Cortex-A12 1166 (all revs) erratum. In very rare timing conditions, a sequence 1167 of VMOV to Core registers instructions, for which the second 1168 one is in the shadow of a branch or abort, can lead to a 1169 deadlock when the VMOV instructions are issued out-of-order. 1170 1171config ARM_ERRATA_825619 1172 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock" 1173 depends on CPU_V7 1174 help 1175 This option enables the workaround for the 825619 Cortex-A12 1176 (all revs) erratum. Within rare timing constraints, executing a 1177 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable 1178 and Device/Strongly-Ordered loads and stores might cause deadlock 1179 1180config ARM_ERRATA_852421 1181 bool "ARM errata: A17: DMB ST might fail to create order between stores" 1182 depends on CPU_V7 1183 help 1184 This option enables the workaround for the 852421 Cortex-A17 1185 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions, 1186 execution of a DMB ST instruction might fail to properly order 1187 stores from GroupA and stores from GroupB. 1188 1189config ARM_ERRATA_852423 1190 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption" 1191 depends on CPU_V7 1192 help 1193 This option enables the workaround for: 1194 - Cortex-A17 852423: Execution of a sequence of instructions might 1195 lead to either a data corruption or a CPU deadlock. Not fixed in 1196 any Cortex-A17 cores yet. 1197 This is identical to Cortex-A12 erratum 852422. It is a separate 1198 config option from the A12 erratum due to the way errata are checked 1199 for and handled. 1200 1201endmenu 1202 1203source "arch/arm/common/Kconfig" 1204 1205menu "Bus support" 1206 1207config ISA 1208 bool 1209 help 1210 Find out whether you have ISA slots on your motherboard. ISA is the 1211 name of a bus system, i.e. the way the CPU talks to the other stuff 1212 inside your box. Other bus systems are PCI, EISA, MicroChannel 1213 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1214 newer boards don't support it. If you have ISA, say Y, otherwise N. 1215 1216# Select ISA DMA controller support 1217config ISA_DMA 1218 bool 1219 select ISA_DMA_API 1220 1221# Select ISA DMA interface 1222config ISA_DMA_API 1223 bool 1224 1225config PCI_NANOENGINE 1226 bool "BSE nanoEngine PCI support" 1227 depends on SA1100_NANOENGINE 1228 help 1229 Enable PCI on the BSE nanoEngine board. 1230 1231config PCI_HOST_ITE8152 1232 bool 1233 depends on PCI && MACH_ARMCORE 1234 default y 1235 select DMABOUNCE 1236 1237endmenu 1238 1239menu "Kernel Features" 1240 1241config HAVE_SMP 1242 bool 1243 help 1244 This option should be selected by machines which have an SMP- 1245 capable CPU. 1246 1247 The only effect of this option is to make the SMP-related 1248 options available to the user for configuration. 1249 1250config SMP 1251 bool "Symmetric Multi-Processing" 1252 depends on CPU_V6K || CPU_V7 1253 depends on GENERIC_CLOCKEVENTS 1254 depends on HAVE_SMP 1255 depends on MMU || ARM_MPU 1256 select IRQ_WORK 1257 help 1258 This enables support for systems with more than one CPU. If you have 1259 a system with only one CPU, say N. If you have a system with more 1260 than one CPU, say Y. 1261 1262 If you say N here, the kernel will run on uni- and multiprocessor 1263 machines, but will use only one CPU of a multiprocessor machine. If 1264 you say Y here, the kernel will run on many, but not all, 1265 uniprocessor machines. On a uniprocessor machine, the kernel 1266 will run faster if you say N here. 1267 1268 See also <file:Documentation/x86/i386/IO-APIC.txt>, 1269 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 1270 <http://tldp.org/HOWTO/SMP-HOWTO.html>. 1271 1272 If you don't know what to do here, say N. 1273 1274config SMP_ON_UP 1275 bool "Allow booting SMP kernel on uniprocessor systems" 1276 depends on SMP && !XIP_KERNEL && MMU 1277 default y 1278 help 1279 SMP kernels contain instructions which fail on non-SMP processors. 1280 Enabling this option allows the kernel to modify itself to make 1281 these instructions safe. Disabling it allows about 1K of space 1282 savings. 1283 1284 If you don't know what to do here, say Y. 1285 1286config ARM_CPU_TOPOLOGY 1287 bool "Support cpu topology definition" 1288 depends on SMP && CPU_V7 1289 default y 1290 help 1291 Support ARM cpu topology definition. The MPIDR register defines 1292 affinity between processors which is then used to describe the cpu 1293 topology of an ARM System. 1294 1295config SCHED_MC 1296 bool "Multi-core scheduler support" 1297 depends on ARM_CPU_TOPOLOGY 1298 help 1299 Multi-core scheduler support improves the CPU scheduler's decision 1300 making when dealing with multi-core CPU chips at a cost of slightly 1301 increased overhead in some places. If unsure say N here. 1302 1303config SCHED_SMT 1304 bool "SMT scheduler support" 1305 depends on ARM_CPU_TOPOLOGY 1306 help 1307 Improves the CPU scheduler's decision making when dealing with 1308 MultiThreading at a cost of slightly increased overhead in some 1309 places. If unsure say N here. 1310 1311config HAVE_ARM_SCU 1312 bool 1313 help 1314 This option enables support for the ARM snoop control unit 1315 1316config HAVE_ARM_ARCH_TIMER 1317 bool "Architected timer support" 1318 depends on CPU_V7 1319 select ARM_ARCH_TIMER 1320 select GENERIC_CLOCKEVENTS 1321 help 1322 This option enables support for the ARM architected timer 1323 1324config HAVE_ARM_TWD 1325 bool 1326 help 1327 This options enables support for the ARM timer and watchdog unit 1328 1329config MCPM 1330 bool "Multi-Cluster Power Management" 1331 depends on CPU_V7 && SMP 1332 help 1333 This option provides the common power management infrastructure 1334 for (multi-)cluster based systems, such as big.LITTLE based 1335 systems. 1336 1337config MCPM_QUAD_CLUSTER 1338 bool 1339 depends on MCPM 1340 help 1341 To avoid wasting resources unnecessarily, MCPM only supports up 1342 to 2 clusters by default. 1343 Platforms with 3 or 4 clusters that use MCPM must select this 1344 option to allow the additional clusters to be managed. 1345 1346config BIG_LITTLE 1347 bool "big.LITTLE support (Experimental)" 1348 depends on CPU_V7 && SMP 1349 select MCPM 1350 help 1351 This option enables support selections for the big.LITTLE 1352 system architecture. 1353 1354config BL_SWITCHER 1355 bool "big.LITTLE switcher support" 1356 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC 1357 select CPU_PM 1358 help 1359 The big.LITTLE "switcher" provides the core functionality to 1360 transparently handle transition between a cluster of A15's 1361 and a cluster of A7's in a big.LITTLE system. 1362 1363config BL_SWITCHER_DUMMY_IF 1364 tristate "Simple big.LITTLE switcher user interface" 1365 depends on BL_SWITCHER && DEBUG_KERNEL 1366 help 1367 This is a simple and dummy char dev interface to control 1368 the big.LITTLE switcher core code. It is meant for 1369 debugging purposes only. 1370 1371choice 1372 prompt "Memory split" 1373 depends on MMU 1374 default VMSPLIT_3G 1375 help 1376 Select the desired split between kernel and user memory. 1377 1378 If you are not absolutely sure what you are doing, leave this 1379 option alone! 1380 1381 config VMSPLIT_3G 1382 bool "3G/1G user/kernel split" 1383 config VMSPLIT_3G_OPT 1384 depends on !ARM_LPAE 1385 bool "3G/1G user/kernel split (for full 1G low memory)" 1386 config VMSPLIT_2G 1387 bool "2G/2G user/kernel split" 1388 config VMSPLIT_1G 1389 bool "1G/3G user/kernel split" 1390endchoice 1391 1392config PAGE_OFFSET 1393 hex 1394 default PHYS_OFFSET if !MMU 1395 default 0x40000000 if VMSPLIT_1G 1396 default 0x80000000 if VMSPLIT_2G 1397 default 0xB0000000 if VMSPLIT_3G_OPT 1398 default 0xC0000000 1399 1400config NR_CPUS 1401 int "Maximum number of CPUs (2-32)" 1402 range 2 32 1403 depends on SMP 1404 default "4" 1405 1406config HOTPLUG_CPU 1407 bool "Support for hot-pluggable CPUs" 1408 depends on SMP 1409 select GENERIC_IRQ_MIGRATION 1410 help 1411 Say Y here to experiment with turning CPUs off and on. CPUs 1412 can be controlled through /sys/devices/system/cpu. 1413 1414config ARM_PSCI 1415 bool "Support for the ARM Power State Coordination Interface (PSCI)" 1416 depends on HAVE_ARM_SMCCC 1417 select ARM_PSCI_FW 1418 help 1419 Say Y here if you want Linux to communicate with system firmware 1420 implementing the PSCI specification for CPU-centric power 1421 management operations described in ARM document number ARM DEN 1422 0022A ("Power State Coordination Interface System Software on 1423 ARM processors"). 1424 1425# The GPIO number here must be sorted by descending number. In case of 1426# a multiplatform kernel, we just want the highest value required by the 1427# selected platforms. 1428config ARCH_NR_GPIO 1429 int 1430 default 2048 if ARCH_SOCFPGA 1431 default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \ 1432 ARCH_ZYNQ 1433 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \ 1434 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210 1435 default 416 if ARCH_SUNXI 1436 default 392 if ARCH_U8500 1437 default 352 if ARCH_VT8500 1438 default 288 if ARCH_ROCKCHIP 1439 default 264 if MACH_H4700 1440 default 0 1441 help 1442 Maximum number of GPIOs in the system. 1443 1444 If unsure, leave the default value. 1445 1446config HZ_FIXED 1447 int 1448 default 200 if ARCH_EBSA110 1449 default 128 if SOC_AT91RM9200 1450 default 0 1451 1452choice 1453 depends on HZ_FIXED = 0 1454 prompt "Timer frequency" 1455 1456config HZ_100 1457 bool "100 Hz" 1458 1459config HZ_200 1460 bool "200 Hz" 1461 1462config HZ_250 1463 bool "250 Hz" 1464 1465config HZ_300 1466 bool "300 Hz" 1467 1468config HZ_500 1469 bool "500 Hz" 1470 1471config HZ_1000 1472 bool "1000 Hz" 1473 1474endchoice 1475 1476config HZ 1477 int 1478 default HZ_FIXED if HZ_FIXED != 0 1479 default 100 if HZ_100 1480 default 200 if HZ_200 1481 default 250 if HZ_250 1482 default 300 if HZ_300 1483 default 500 if HZ_500 1484 default 1000 1485 1486config SCHED_HRTICK 1487 def_bool HIGH_RES_TIMERS 1488 1489config THUMB2_KERNEL 1490 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY 1491 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K 1492 default y if CPU_THUMBONLY 1493 select ARM_UNWIND 1494 help 1495 By enabling this option, the kernel will be compiled in 1496 Thumb-2 mode. 1497 1498 If unsure, say N. 1499 1500config THUMB2_AVOID_R_ARM_THM_JUMP11 1501 bool "Work around buggy Thumb-2 short branch relocations in gas" 1502 depends on THUMB2_KERNEL && MODULES 1503 default y 1504 help 1505 Various binutils versions can resolve Thumb-2 branches to 1506 locally-defined, preemptible global symbols as short-range "b.n" 1507 branch instructions. 1508 1509 This is a problem, because there's no guarantee the final 1510 destination of the symbol, or any candidate locations for a 1511 trampoline, are within range of the branch. For this reason, the 1512 kernel does not support fixing up the R_ARM_THM_JUMP11 (102) 1513 relocation in modules at all, and it makes little sense to add 1514 support. 1515 1516 The symptom is that the kernel fails with an "unsupported 1517 relocation" error when loading some modules. 1518 1519 Until fixed tools are available, passing 1520 -fno-optimize-sibling-calls to gcc should prevent gcc generating 1521 code which hits this problem, at the cost of a bit of extra runtime 1522 stack usage in some cases. 1523 1524 The problem is described in more detail at: 1525 https://bugs.launchpad.net/binutils-linaro/+bug/725126 1526 1527 Only Thumb-2 kernels are affected. 1528 1529 Unless you are sure your tools don't have this problem, say Y. 1530 1531config ARM_PATCH_IDIV 1532 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()" 1533 depends on CPU_32v7 && !XIP_KERNEL 1534 default y 1535 help 1536 The ARM compiler inserts calls to __aeabi_idiv() and 1537 __aeabi_uidiv() when it needs to perform division on signed 1538 and unsigned integers. Some v7 CPUs have support for the sdiv 1539 and udiv instructions that can be used to implement those 1540 functions. 1541 1542 Enabling this option allows the kernel to modify itself to 1543 replace the first two instructions of these library functions 1544 with the sdiv or udiv plus "bx lr" instructions when the CPU 1545 it is running on supports them. Typically this will be faster 1546 and less power intensive than running the original library 1547 code to do integer division. 1548 1549config AEABI 1550 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && !CPU_V7M && !CPU_V6 && !CPU_V6K 1551 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K 1552 help 1553 This option allows for the kernel to be compiled using the latest 1554 ARM ABI (aka EABI). This is only useful if you are using a user 1555 space environment that is also compiled with EABI. 1556 1557 Since there are major incompatibilities between the legacy ABI and 1558 EABI, especially with regard to structure member alignment, this 1559 option also changes the kernel syscall calling convention to 1560 disambiguate both ABIs and allow for backward compatibility support 1561 (selected with CONFIG_OABI_COMPAT). 1562 1563 To use this you need GCC version 4.0.0 or later. 1564 1565config OABI_COMPAT 1566 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)" 1567 depends on AEABI && !THUMB2_KERNEL 1568 help 1569 This option preserves the old syscall interface along with the 1570 new (ARM EABI) one. It also provides a compatibility layer to 1571 intercept syscalls that have structure arguments which layout 1572 in memory differs between the legacy ABI and the new ARM EABI 1573 (only for non "thumb" binaries). This option adds a tiny 1574 overhead to all syscalls and produces a slightly larger kernel. 1575 1576 The seccomp filter system will not be available when this is 1577 selected, since there is no way yet to sensibly distinguish 1578 between calling conventions during filtering. 1579 1580 If you know you'll be using only pure EABI user space then you 1581 can say N here. If this option is not selected and you attempt 1582 to execute a legacy ABI binary then the result will be 1583 UNPREDICTABLE (in fact it can be predicted that it won't work 1584 at all). If in doubt say N. 1585 1586config ARCH_HAS_HOLES_MEMORYMODEL 1587 bool 1588 1589config ARCH_SPARSEMEM_ENABLE 1590 bool 1591 1592config ARCH_SPARSEMEM_DEFAULT 1593 def_bool ARCH_SPARSEMEM_ENABLE 1594 1595config ARCH_SELECT_MEMORY_MODEL 1596 def_bool ARCH_SPARSEMEM_ENABLE 1597 1598config HAVE_ARCH_PFN_VALID 1599 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM 1600 1601config HAVE_GENERIC_GUP 1602 def_bool y 1603 depends on ARM_LPAE 1604 1605config HIGHMEM 1606 bool "High Memory Support" 1607 depends on MMU 1608 help 1609 The address space of ARM processors is only 4 Gigabytes large 1610 and it has to accommodate user address space, kernel address 1611 space as well as some memory mapped IO. That means that, if you 1612 have a large amount of physical memory and/or IO, not all of the 1613 memory can be "permanently mapped" by the kernel. The physical 1614 memory that is not permanently mapped is called "high memory". 1615 1616 Depending on the selected kernel/user memory split, minimum 1617 vmalloc space and actual amount of RAM, you may not need this 1618 option which should result in a slightly faster kernel. 1619 1620 If unsure, say n. 1621 1622config HIGHPTE 1623 bool "Allocate 2nd-level pagetables from highmem" if EXPERT 1624 depends on HIGHMEM 1625 default y 1626 help 1627 The VM uses one page of physical memory for each page table. 1628 For systems with a lot of processes, this can use a lot of 1629 precious low memory, eventually leading to low memory being 1630 consumed by page tables. Setting this option will allow 1631 user-space 2nd level page tables to reside in high memory. 1632 1633config CPU_SW_DOMAIN_PAN 1634 bool "Enable use of CPU domains to implement privileged no-access" 1635 depends on MMU && !ARM_LPAE 1636 default y 1637 help 1638 Increase kernel security by ensuring that normal kernel accesses 1639 are unable to access userspace addresses. This can help prevent 1640 use-after-free bugs becoming an exploitable privilege escalation 1641 by ensuring that magic values (such as LIST_POISON) will always 1642 fault when dereferenced. 1643 1644 CPUs with low-vector mappings use a best-efforts implementation. 1645 Their lower 1MB needs to remain accessible for the vectors, but 1646 the remainder of userspace will become appropriately inaccessible. 1647 1648config HW_PERF_EVENTS 1649 def_bool y 1650 depends on ARM_PMU 1651 1652config SYS_SUPPORTS_HUGETLBFS 1653 def_bool y 1654 depends on ARM_LPAE 1655 1656config HAVE_ARCH_TRANSPARENT_HUGEPAGE 1657 def_bool y 1658 depends on ARM_LPAE 1659 1660config ARCH_WANT_GENERAL_HUGETLB 1661 def_bool y 1662 1663config ARM_MODULE_PLTS 1664 bool "Use PLTs to allow module memory to spill over into vmalloc area" 1665 depends on MODULES 1666 default y 1667 help 1668 Allocate PLTs when loading modules so that jumps and calls whose 1669 targets are too far away for their relative offsets to be encoded 1670 in the instructions themselves can be bounced via veneers in the 1671 module's PLT. This allows modules to be allocated in the generic 1672 vmalloc area after the dedicated module memory area has been 1673 exhausted. The modules will use slightly more memory, but after 1674 rounding up to page size, the actual memory footprint is usually 1675 the same. 1676 1677 Disabling this is usually safe for small single-platform 1678 configurations. If unsure, say y. 1679 1680config FORCE_MAX_ZONEORDER 1681 int "Maximum zone order" 1682 default "12" if SOC_AM33XX 1683 default "9" if SA1111 || ARCH_EFM32 1684 default "11" 1685 help 1686 The kernel memory allocator divides physically contiguous memory 1687 blocks into "zones", where each zone is a power of two number of 1688 pages. This option selects the largest power of two that the kernel 1689 keeps in the memory allocator. If you need to allocate very large 1690 blocks of physically contiguous memory, then you may need to 1691 increase this value. 1692 1693 This config option is actually maximum order plus one. For example, 1694 a value of 11 means that the largest free memory block is 2^10 pages. 1695 1696config ALIGNMENT_TRAP 1697 bool 1698 depends on CPU_CP15_MMU 1699 default y if !ARCH_EBSA110 1700 select HAVE_PROC_CPU if PROC_FS 1701 help 1702 ARM processors cannot fetch/store information which is not 1703 naturally aligned on the bus, i.e., a 4 byte fetch must start at an 1704 address divisible by 4. On 32-bit ARM processors, these non-aligned 1705 fetch/store instructions will be emulated in software if you say 1706 here, which has a severe performance impact. This is necessary for 1707 correct operation of some network protocols. With an IP-only 1708 configuration it is safe to say N, otherwise say Y. 1709 1710config UACCESS_WITH_MEMCPY 1711 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()" 1712 depends on MMU 1713 default y if CPU_FEROCEON 1714 help 1715 Implement faster copy_to_user and clear_user methods for CPU 1716 cores where a 8-word STM instruction give significantly higher 1717 memory write throughput than a sequence of individual 32bit stores. 1718 1719 A possible side effect is a slight increase in scheduling latency 1720 between threads sharing the same address space if they invoke 1721 such copy operations with large buffers. 1722 1723 However, if the CPU data cache is using a write-allocate mode, 1724 this option is unlikely to provide any performance gain. 1725 1726config SECCOMP 1727 bool 1728 prompt "Enable seccomp to safely compute untrusted bytecode" 1729 ---help--- 1730 This kernel feature is useful for number crunching applications 1731 that may need to compute untrusted bytecode during their 1732 execution. By using pipes or other transports made available to 1733 the process as file descriptors supporting the read/write 1734 syscalls, it's possible to isolate those applications in 1735 their own address space using seccomp. Once seccomp is 1736 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1737 and the task is only allowed to execute a few safe syscalls 1738 defined by each seccomp mode. 1739 1740config PARAVIRT 1741 bool "Enable paravirtualization code" 1742 help 1743 This changes the kernel so it can modify itself when it is run 1744 under a hypervisor, potentially improving performance significantly 1745 over full virtualization. 1746 1747config PARAVIRT_TIME_ACCOUNTING 1748 bool "Paravirtual steal time accounting" 1749 select PARAVIRT 1750 help 1751 Select this option to enable fine granularity task steal time 1752 accounting. Time spent executing other tasks in parallel with 1753 the current vCPU is discounted from the vCPU power. To account for 1754 that, there can be a small performance impact. 1755 1756 If in doubt, say N here. 1757 1758config XEN_DOM0 1759 def_bool y 1760 depends on XEN 1761 1762config XEN 1763 bool "Xen guest support on ARM" 1764 depends on ARM && AEABI && OF 1765 depends on CPU_V7 && !CPU_V6 1766 depends on !GENERIC_ATOMIC64 1767 depends on MMU 1768 select ARCH_DMA_ADDR_T_64BIT 1769 select ARM_PSCI 1770 select SWIOTLB 1771 select SWIOTLB_XEN 1772 select PARAVIRT 1773 help 1774 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. 1775 1776config STACKPROTECTOR_PER_TASK 1777 bool "Use a unique stack canary value for each task" 1778 depends on GCC_PLUGINS && STACKPROTECTOR && SMP && !XIP_DEFLATED_DATA 1779 select GCC_PLUGIN_ARM_SSP_PER_TASK 1780 default y 1781 help 1782 Due to the fact that GCC uses an ordinary symbol reference from 1783 which to load the value of the stack canary, this value can only 1784 change at reboot time on SMP systems, and all tasks running in the 1785 kernel's address space are forced to use the same canary value for 1786 the entire duration that the system is up. 1787 1788 Enable this option to switch to a different method that uses a 1789 different canary value for each task. 1790 1791endmenu 1792 1793menu "Boot options" 1794 1795config USE_OF 1796 bool "Flattened Device Tree support" 1797 select IRQ_DOMAIN 1798 select OF 1799 help 1800 Include support for flattened device tree machine descriptions. 1801 1802config ATAGS 1803 bool "Support for the traditional ATAGS boot data passing" if USE_OF 1804 default y 1805 help 1806 This is the traditional way of passing data to the kernel at boot 1807 time. If you are solely relying on the flattened device tree (or 1808 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option 1809 to remove ATAGS support from your kernel binary. If unsure, 1810 leave this to y. 1811 1812config DEPRECATED_PARAM_STRUCT 1813 bool "Provide old way to pass kernel parameters" 1814 depends on ATAGS 1815 help 1816 This was deprecated in 2001 and announced to live on for 5 years. 1817 Some old boot loaders still use this way. 1818 1819# Compressed boot loader in ROM. Yes, we really want to ask about 1820# TEXT and BSS so we preserve their values in the config files. 1821config ZBOOT_ROM_TEXT 1822 hex "Compressed ROM boot loader base address" 1823 default "0" 1824 help 1825 The physical address at which the ROM-able zImage is to be 1826 placed in the target. Platforms which normally make use of 1827 ROM-able zImage formats normally set this to a suitable 1828 value in their defconfig file. 1829 1830 If ZBOOT_ROM is not enabled, this has no effect. 1831 1832config ZBOOT_ROM_BSS 1833 hex "Compressed ROM boot loader BSS address" 1834 default "0" 1835 help 1836 The base address of an area of read/write memory in the target 1837 for the ROM-able zImage which must be available while the 1838 decompressor is running. It must be large enough to hold the 1839 entire decompressed kernel plus an additional 128 KiB. 1840 Platforms which normally make use of ROM-able zImage formats 1841 normally set this to a suitable value in their defconfig file. 1842 1843 If ZBOOT_ROM is not enabled, this has no effect. 1844 1845config ZBOOT_ROM 1846 bool "Compressed boot loader in ROM/flash" 1847 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS 1848 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR 1849 help 1850 Say Y here if you intend to execute your compressed kernel image 1851 (zImage) directly from ROM or flash. If unsure, say N. 1852 1853config ARM_APPENDED_DTB 1854 bool "Use appended device tree blob to zImage (EXPERIMENTAL)" 1855 depends on OF 1856 help 1857 With this option, the boot code will look for a device tree binary 1858 (DTB) appended to zImage 1859 (e.g. cat zImage <filename>.dtb > zImage_w_dtb). 1860 1861 This is meant as a backward compatibility convenience for those 1862 systems with a bootloader that can't be upgraded to accommodate 1863 the documented boot protocol using a device tree. 1864 1865 Beware that there is very little in terms of protection against 1866 this option being confused by leftover garbage in memory that might 1867 look like a DTB header after a reboot if no actual DTB is appended 1868 to zImage. Do not leave this option active in a production kernel 1869 if you don't intend to always append a DTB. Proper passing of the 1870 location into r2 of a bootloader provided DTB is always preferable 1871 to this option. 1872 1873config ARM_ATAG_DTB_COMPAT 1874 bool "Supplement the appended DTB with traditional ATAG information" 1875 depends on ARM_APPENDED_DTB 1876 help 1877 Some old bootloaders can't be updated to a DTB capable one, yet 1878 they provide ATAGs with memory configuration, the ramdisk address, 1879 the kernel cmdline string, etc. Such information is dynamically 1880 provided by the bootloader and can't always be stored in a static 1881 DTB. To allow a device tree enabled kernel to be used with such 1882 bootloaders, this option allows zImage to extract the information 1883 from the ATAG list and store it at run time into the appended DTB. 1884 1885choice 1886 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT 1887 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1888 1889config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1890 bool "Use bootloader kernel arguments if available" 1891 help 1892 Uses the command-line options passed by the boot loader instead of 1893 the device tree bootargs property. If the boot loader doesn't provide 1894 any, the device tree bootargs property will be used. 1895 1896config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND 1897 bool "Extend with bootloader kernel arguments" 1898 help 1899 The command-line arguments provided by the boot loader will be 1900 appended to the the device tree bootargs property. 1901 1902endchoice 1903 1904config CMDLINE 1905 string "Default kernel command string" 1906 default "" 1907 help 1908 On some architectures (EBSA110 and CATS), there is currently no way 1909 for the boot loader to pass arguments to the kernel. For these 1910 architectures, you should supply some command-line options at build 1911 time by entering them here. As a minimum, you should specify the 1912 memory size and the root device (e.g., mem=64M root=/dev/nfs). 1913 1914choice 1915 prompt "Kernel command line type" if CMDLINE != "" 1916 default CMDLINE_FROM_BOOTLOADER 1917 depends on ATAGS 1918 1919config CMDLINE_FROM_BOOTLOADER 1920 bool "Use bootloader kernel arguments if available" 1921 help 1922 Uses the command-line options passed by the boot loader. If 1923 the boot loader doesn't provide any, the default kernel command 1924 string provided in CMDLINE will be used. 1925 1926config CMDLINE_EXTEND 1927 bool "Extend bootloader kernel arguments" 1928 help 1929 The command-line arguments provided by the boot loader will be 1930 appended to the default kernel command string. 1931 1932config CMDLINE_FORCE 1933 bool "Always use the default kernel command string" 1934 help 1935 Always use the default kernel command string, even if the boot 1936 loader passes other arguments to the kernel. 1937 This is useful if you cannot or don't want to change the 1938 command-line options your boot loader passes to the kernel. 1939endchoice 1940 1941config XIP_KERNEL 1942 bool "Kernel Execute-In-Place from ROM" 1943 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM 1944 help 1945 Execute-In-Place allows the kernel to run from non-volatile storage 1946 directly addressable by the CPU, such as NOR flash. This saves RAM 1947 space since the text section of the kernel is not loaded from flash 1948 to RAM. Read-write sections, such as the data section and stack, 1949 are still copied to RAM. The XIP kernel is not compressed since 1950 it has to run directly from flash, so it will take more space to 1951 store it. The flash address used to link the kernel object files, 1952 and for storing it, is configuration dependent. Therefore, if you 1953 say Y here, you must know the proper physical address where to 1954 store the kernel image depending on your own flash memory usage. 1955 1956 Also note that the make target becomes "make xipImage" rather than 1957 "make zImage" or "make Image". The final kernel binary to put in 1958 ROM memory will be arch/arm/boot/xipImage. 1959 1960 If unsure, say N. 1961 1962config XIP_PHYS_ADDR 1963 hex "XIP Kernel Physical Location" 1964 depends on XIP_KERNEL 1965 default "0x00080000" 1966 help 1967 This is the physical address in your flash memory the kernel will 1968 be linked for and stored to. This address is dependent on your 1969 own flash usage. 1970 1971config XIP_DEFLATED_DATA 1972 bool "Store kernel .data section compressed in ROM" 1973 depends on XIP_KERNEL 1974 select ZLIB_INFLATE 1975 help 1976 Before the kernel is actually executed, its .data section has to be 1977 copied to RAM from ROM. This option allows for storing that data 1978 in compressed form and decompressed to RAM rather than merely being 1979 copied, saving some precious ROM space. A possible drawback is a 1980 slightly longer boot delay. 1981 1982config KEXEC 1983 bool "Kexec system call (EXPERIMENTAL)" 1984 depends on (!SMP || PM_SLEEP_SMP) 1985 depends on !CPU_V7M 1986 select KEXEC_CORE 1987 help 1988 kexec is a system call that implements the ability to shutdown your 1989 current kernel, and to start another kernel. It is like a reboot 1990 but it is independent of the system firmware. And like a reboot 1991 you can start any kernel with it, not just Linux. 1992 1993 It is an ongoing process to be certain the hardware in a machine 1994 is properly shutdown, so do not be surprised if this code does not 1995 initially work for you. 1996 1997config ATAGS_PROC 1998 bool "Export atags in procfs" 1999 depends on ATAGS && KEXEC 2000 default y 2001 help 2002 Should the atags used to boot the kernel be exported in an "atags" 2003 file in procfs. Useful with kexec. 2004 2005config CRASH_DUMP 2006 bool "Build kdump crash kernel (EXPERIMENTAL)" 2007 help 2008 Generate crash dump after being started by kexec. This should 2009 be normally only set in special crash dump kernels which are 2010 loaded in the main kernel with kexec-tools into a specially 2011 reserved region and then later executed after a crash by 2012 kdump/kexec. The crash dump kernel must be compiled to a 2013 memory address not used by the main kernel 2014 2015 For more details see Documentation/kdump/kdump.txt 2016 2017config AUTO_ZRELADDR 2018 bool "Auto calculation of the decompressed kernel image address" 2019 help 2020 ZRELADDR is the physical address where the decompressed kernel 2021 image will be placed. If AUTO_ZRELADDR is selected, the address 2022 will be determined at run-time by masking the current IP with 2023 0xf8000000. This assumes the zImage being placed in the first 128MB 2024 from start of memory. 2025 2026config EFI_STUB 2027 bool 2028 2029config EFI 2030 bool "UEFI runtime support" 2031 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL 2032 select UCS2_STRING 2033 select EFI_PARAMS_FROM_FDT 2034 select EFI_STUB 2035 select EFI_ARMSTUB 2036 select EFI_RUNTIME_WRAPPERS 2037 ---help--- 2038 This option provides support for runtime services provided 2039 by UEFI firmware (such as non-volatile variables, realtime 2040 clock, and platform reset). A UEFI stub is also provided to 2041 allow the kernel to be booted as an EFI application. This 2042 is only useful for kernels that may run on systems that have 2043 UEFI firmware. 2044 2045config DMI 2046 bool "Enable support for SMBIOS (DMI) tables" 2047 depends on EFI 2048 default y 2049 help 2050 This enables SMBIOS/DMI feature for systems. 2051 2052 This option is only useful on systems that have UEFI firmware. 2053 However, even with this option, the resultant kernel should 2054 continue to boot on existing non-UEFI platforms. 2055 2056 NOTE: This does *NOT* enable or encourage the use of DMI quirks, 2057 i.e., the the practice of identifying the platform via DMI to 2058 decide whether certain workarounds for buggy hardware and/or 2059 firmware need to be enabled. This would require the DMI subsystem 2060 to be enabled much earlier than we do on ARM, which is non-trivial. 2061 2062endmenu 2063 2064menu "CPU Power Management" 2065 2066source "drivers/cpufreq/Kconfig" 2067 2068source "drivers/cpuidle/Kconfig" 2069 2070endmenu 2071 2072menu "Floating point emulation" 2073 2074comment "At least one emulation must be selected" 2075 2076config FPE_NWFPE 2077 bool "NWFPE math emulation" 2078 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL 2079 ---help--- 2080 Say Y to include the NWFPE floating point emulator in the kernel. 2081 This is necessary to run most binaries. Linux does not currently 2082 support floating point hardware so you need to say Y here even if 2083 your machine has an FPA or floating point co-processor podule. 2084 2085 You may say N here if you are going to load the Acorn FPEmulator 2086 early in the bootup. 2087 2088config FPE_NWFPE_XP 2089 bool "Support extended precision" 2090 depends on FPE_NWFPE 2091 help 2092 Say Y to include 80-bit support in the kernel floating-point 2093 emulator. Otherwise, only 32 and 64-bit support is compiled in. 2094 Note that gcc does not generate 80-bit operations by default, 2095 so in most cases this option only enlarges the size of the 2096 floating point emulator without any good reason. 2097 2098 You almost surely want to say N here. 2099 2100config FPE_FASTFPE 2101 bool "FastFPE math emulation (EXPERIMENTAL)" 2102 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 2103 ---help--- 2104 Say Y here to include the FAST floating point emulator in the kernel. 2105 This is an experimental much faster emulator which now also has full 2106 precision for the mantissa. It does not support any exceptions. 2107 It is very simple, and approximately 3-6 times faster than NWFPE. 2108 2109 It should be sufficient for most programs. It may be not suitable 2110 for scientific calculations, but you have to check this for yourself. 2111 If you do not feel you need a faster FP emulation you should better 2112 choose NWFPE. 2113 2114config VFP 2115 bool "VFP-format floating point maths" 2116 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON 2117 help 2118 Say Y to include VFP support code in the kernel. This is needed 2119 if your hardware includes a VFP unit. 2120 2121 Please see <file:Documentation/arm/VFP/release-notes.txt> for 2122 release notes and additional status information. 2123 2124 Say N if your target does not have VFP hardware. 2125 2126config VFPv3 2127 bool 2128 depends on VFP 2129 default y if CPU_V7 2130 2131config NEON 2132 bool "Advanced SIMD (NEON) Extension support" 2133 depends on VFPv3 && CPU_V7 2134 help 2135 Say Y to include support code for NEON, the ARMv7 Advanced SIMD 2136 Extension. 2137 2138config KERNEL_MODE_NEON 2139 bool "Support for NEON in kernel mode" 2140 depends on NEON && AEABI 2141 help 2142 Say Y to include support for NEON in kernel mode. 2143 2144endmenu 2145 2146menu "Power management options" 2147 2148source "kernel/power/Kconfig" 2149 2150config ARCH_SUSPEND_POSSIBLE 2151 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \ 2152 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK 2153 def_bool y 2154 2155config ARM_CPU_SUSPEND 2156 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW 2157 depends on ARCH_SUSPEND_POSSIBLE 2158 2159config ARCH_HIBERNATION_POSSIBLE 2160 bool 2161 depends on MMU 2162 default y if ARCH_SUSPEND_POSSIBLE 2163 2164endmenu 2165 2166source "drivers/firmware/Kconfig" 2167 2168if CRYPTO 2169source "arch/arm/crypto/Kconfig" 2170endif 2171 2172source "arch/arm/kvm/Kconfig" 2173