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 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 RESET_CONTROLLER 600 select SPARSE_IRQ 601 select USE_OF 602 select ZONE_DMA 603 help 604 Support for TI's DaVinci platform. 605 606config ARCH_OMAP1 607 bool "TI OMAP1" 608 depends on MMU 609 select ARCH_HAS_HOLES_MEMORYMODEL 610 select ARCH_OMAP 611 select CLKDEV_LOOKUP 612 select CLKSRC_MMIO 613 select GENERIC_CLOCKEVENTS 614 select GENERIC_IRQ_CHIP 615 select GENERIC_IRQ_MULTI_HANDLER 616 select GPIOLIB 617 select HAVE_IDE 618 select IRQ_DOMAIN 619 select NEED_MACH_IO_H if PCCARD 620 select NEED_MACH_MEMORY_H 621 select SPARSE_IRQ 622 help 623 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx) 624 625endchoice 626 627menu "Multiple platform selection" 628 depends on ARCH_MULTIPLATFORM 629 630comment "CPU Core family selection" 631 632config ARCH_MULTI_V4 633 bool "ARMv4 based platforms (FA526)" 634 depends on !ARCH_MULTI_V6_V7 635 select ARCH_MULTI_V4_V5 636 select CPU_FA526 637 638config ARCH_MULTI_V4T 639 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)" 640 depends on !ARCH_MULTI_V6_V7 641 select ARCH_MULTI_V4_V5 642 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \ 643 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \ 644 CPU_ARM925T || CPU_ARM940T) 645 646config ARCH_MULTI_V5 647 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)" 648 depends on !ARCH_MULTI_V6_V7 649 select ARCH_MULTI_V4_V5 650 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \ 651 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \ 652 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON) 653 654config ARCH_MULTI_V4_V5 655 bool 656 657config ARCH_MULTI_V6 658 bool "ARMv6 based platforms (ARM11)" 659 select ARCH_MULTI_V6_V7 660 select CPU_V6K 661 662config ARCH_MULTI_V7 663 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)" 664 default y 665 select ARCH_MULTI_V6_V7 666 select CPU_V7 667 select HAVE_SMP 668 669config ARCH_MULTI_V6_V7 670 bool 671 select MIGHT_HAVE_CACHE_L2X0 672 673config ARCH_MULTI_CPU_AUTO 674 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7) 675 select ARCH_MULTI_V5 676 677endmenu 678 679config ARCH_VIRT 680 bool "Dummy Virtual Machine" 681 depends on ARCH_MULTI_V7 682 select ARM_AMBA 683 select ARM_GIC 684 select ARM_GIC_V2M if PCI 685 select ARM_GIC_V3 686 select ARM_GIC_V3_ITS if PCI 687 select ARM_PSCI 688 select HAVE_ARM_ARCH_TIMER 689 select ARCH_SUPPORTS_BIG_ENDIAN 690 691# 692# This is sorted alphabetically by mach-* pathname. However, plat-* 693# Kconfigs may be included either alphabetically (according to the 694# plat- suffix) or along side the corresponding mach-* source. 695# 696source "arch/arm/mach-actions/Kconfig" 697 698source "arch/arm/mach-alpine/Kconfig" 699 700source "arch/arm/mach-artpec/Kconfig" 701 702source "arch/arm/mach-asm9260/Kconfig" 703 704source "arch/arm/mach-aspeed/Kconfig" 705 706source "arch/arm/mach-at91/Kconfig" 707 708source "arch/arm/mach-axxia/Kconfig" 709 710source "arch/arm/mach-bcm/Kconfig" 711 712source "arch/arm/mach-berlin/Kconfig" 713 714source "arch/arm/mach-clps711x/Kconfig" 715 716source "arch/arm/mach-cns3xxx/Kconfig" 717 718source "arch/arm/mach-davinci/Kconfig" 719 720source "arch/arm/mach-digicolor/Kconfig" 721 722source "arch/arm/mach-dove/Kconfig" 723 724source "arch/arm/mach-ep93xx/Kconfig" 725 726source "arch/arm/mach-exynos/Kconfig" 727source "arch/arm/plat-samsung/Kconfig" 728 729source "arch/arm/mach-footbridge/Kconfig" 730 731source "arch/arm/mach-gemini/Kconfig" 732 733source "arch/arm/mach-highbank/Kconfig" 734 735source "arch/arm/mach-hisi/Kconfig" 736 737source "arch/arm/mach-imx/Kconfig" 738 739source "arch/arm/mach-integrator/Kconfig" 740 741source "arch/arm/mach-iop13xx/Kconfig" 742 743source "arch/arm/mach-iop32x/Kconfig" 744 745source "arch/arm/mach-iop33x/Kconfig" 746 747source "arch/arm/mach-ixp4xx/Kconfig" 748 749source "arch/arm/mach-keystone/Kconfig" 750 751source "arch/arm/mach-ks8695/Kconfig" 752 753source "arch/arm/mach-mediatek/Kconfig" 754 755source "arch/arm/mach-meson/Kconfig" 756 757source "arch/arm/mach-milbeaut/Kconfig" 758 759source "arch/arm/mach-mmp/Kconfig" 760 761source "arch/arm/mach-moxart/Kconfig" 762 763source "arch/arm/mach-mv78xx0/Kconfig" 764 765source "arch/arm/mach-mvebu/Kconfig" 766 767source "arch/arm/mach-mxs/Kconfig" 768 769source "arch/arm/mach-netx/Kconfig" 770 771source "arch/arm/mach-nomadik/Kconfig" 772 773source "arch/arm/mach-npcm/Kconfig" 774 775source "arch/arm/mach-nspire/Kconfig" 776 777source "arch/arm/plat-omap/Kconfig" 778 779source "arch/arm/mach-omap1/Kconfig" 780 781source "arch/arm/mach-omap2/Kconfig" 782 783source "arch/arm/mach-orion5x/Kconfig" 784 785source "arch/arm/mach-oxnas/Kconfig" 786 787source "arch/arm/mach-picoxcell/Kconfig" 788 789source "arch/arm/mach-prima2/Kconfig" 790 791source "arch/arm/mach-pxa/Kconfig" 792source "arch/arm/plat-pxa/Kconfig" 793 794source "arch/arm/mach-qcom/Kconfig" 795 796source "arch/arm/mach-rda/Kconfig" 797 798source "arch/arm/mach-realview/Kconfig" 799 800source "arch/arm/mach-rockchip/Kconfig" 801 802source "arch/arm/mach-s3c24xx/Kconfig" 803 804source "arch/arm/mach-s3c64xx/Kconfig" 805 806source "arch/arm/mach-s5pv210/Kconfig" 807 808source "arch/arm/mach-sa1100/Kconfig" 809 810source "arch/arm/mach-shmobile/Kconfig" 811 812source "arch/arm/mach-socfpga/Kconfig" 813 814source "arch/arm/mach-spear/Kconfig" 815 816source "arch/arm/mach-sti/Kconfig" 817 818source "arch/arm/mach-stm32/Kconfig" 819 820source "arch/arm/mach-sunxi/Kconfig" 821 822source "arch/arm/mach-tango/Kconfig" 823 824source "arch/arm/mach-tegra/Kconfig" 825 826source "arch/arm/mach-u300/Kconfig" 827 828source "arch/arm/mach-uniphier/Kconfig" 829 830source "arch/arm/mach-ux500/Kconfig" 831 832source "arch/arm/mach-versatile/Kconfig" 833 834source "arch/arm/mach-vexpress/Kconfig" 835source "arch/arm/plat-versatile/Kconfig" 836 837source "arch/arm/mach-vt8500/Kconfig" 838 839source "arch/arm/mach-w90x900/Kconfig" 840 841source "arch/arm/mach-zx/Kconfig" 842 843source "arch/arm/mach-zynq/Kconfig" 844 845# ARMv7-M architecture 846config ARCH_EFM32 847 bool "Energy Micro efm32" 848 depends on ARM_SINGLE_ARMV7M 849 select GPIOLIB 850 help 851 Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko 852 processors. 853 854config ARCH_LPC18XX 855 bool "NXP LPC18xx/LPC43xx" 856 depends on ARM_SINGLE_ARMV7M 857 select ARCH_HAS_RESET_CONTROLLER 858 select ARM_AMBA 859 select CLKSRC_LPC32XX 860 select PINCTRL 861 help 862 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4 863 high performance microcontrollers. 864 865config ARCH_MPS2 866 bool "ARM MPS2 platform" 867 depends on ARM_SINGLE_ARMV7M 868 select ARM_AMBA 869 select CLKSRC_MPS2 870 help 871 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes 872 with a range of available cores like Cortex-M3/M4/M7. 873 874 Please, note that depends which Application Note is used memory map 875 for the platform may vary, so adjustment of RAM base might be needed. 876 877# Definitions to make life easier 878config ARCH_ACORN 879 bool 880 881config PLAT_IOP 882 bool 883 select GENERIC_CLOCKEVENTS 884 885config PLAT_ORION 886 bool 887 select CLKSRC_MMIO 888 select COMMON_CLK 889 select GENERIC_IRQ_CHIP 890 select IRQ_DOMAIN 891 892config PLAT_ORION_LEGACY 893 bool 894 select PLAT_ORION 895 896config PLAT_PXA 897 bool 898 899config PLAT_VERSATILE 900 bool 901 902source "arch/arm/firmware/Kconfig" 903 904source "arch/arm/mm/Kconfig" 905 906config IWMMXT 907 bool "Enable iWMMXt support" 908 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B 909 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B 910 help 911 Enable support for iWMMXt context switching at run time if 912 running on a CPU that supports it. 913 914if !MMU 915source "arch/arm/Kconfig-nommu" 916endif 917 918config PJ4B_ERRATA_4742 919 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation" 920 depends on CPU_PJ4B && MACH_ARMADA_370 921 default y 922 help 923 When coming out of either a Wait for Interrupt (WFI) or a Wait for 924 Event (WFE) IDLE states, a specific timing sensitivity exists between 925 the retiring WFI/WFE instructions and the newly issued subsequent 926 instructions. This sensitivity can result in a CPU hang scenario. 927 Workaround: 928 The software must insert either a Data Synchronization Barrier (DSB) 929 or Data Memory Barrier (DMB) command immediately after the WFI/WFE 930 instruction 931 932config ARM_ERRATA_326103 933 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory" 934 depends on CPU_V6 935 help 936 Executing a SWP instruction to read-only memory does not set bit 11 937 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to 938 treat the access as a read, preventing a COW from occurring and 939 causing the faulting task to livelock. 940 941config ARM_ERRATA_411920 942 bool "ARM errata: Invalidation of the Instruction Cache operation can fail" 943 depends on CPU_V6 || CPU_V6K 944 help 945 Invalidation of the Instruction Cache operation can 946 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176. 947 It does not affect the MPCore. This option enables the ARM Ltd. 948 recommended workaround. 949 950config ARM_ERRATA_430973 951 bool "ARM errata: Stale prediction on replaced interworking branch" 952 depends on CPU_V7 953 help 954 This option enables the workaround for the 430973 Cortex-A8 955 r1p* erratum. If a code sequence containing an ARM/Thumb 956 interworking branch is replaced with another code sequence at the 957 same virtual address, whether due to self-modifying code or virtual 958 to physical address re-mapping, Cortex-A8 does not recover from the 959 stale interworking branch prediction. This results in Cortex-A8 960 executing the new code sequence in the incorrect ARM or Thumb state. 961 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE 962 and also flushes the branch target cache at every context switch. 963 Note that setting specific bits in the ACTLR register may not be 964 available in non-secure mode. 965 966config ARM_ERRATA_458693 967 bool "ARM errata: Processor deadlock when a false hazard is created" 968 depends on CPU_V7 969 depends on !ARCH_MULTIPLATFORM 970 help 971 This option enables the workaround for the 458693 Cortex-A8 (r2p0) 972 erratum. For very specific sequences of memory operations, it is 973 possible for a hazard condition intended for a cache line to instead 974 be incorrectly associated with a different cache line. This false 975 hazard might then cause a processor deadlock. The workaround enables 976 the L1 caching of the NEON accesses and disables the PLD instruction 977 in the ACTLR register. Note that setting specific bits in the ACTLR 978 register may not be available in non-secure mode. 979 980config ARM_ERRATA_460075 981 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data" 982 depends on CPU_V7 983 depends on !ARCH_MULTIPLATFORM 984 help 985 This option enables the workaround for the 460075 Cortex-A8 (r2p0) 986 erratum. Any asynchronous access to the L2 cache may encounter a 987 situation in which recent store transactions to the L2 cache are lost 988 and overwritten with stale memory contents from external memory. The 989 workaround disables the write-allocate mode for the L2 cache via the 990 ACTLR register. Note that setting specific bits in the ACTLR register 991 may not be available in non-secure mode. 992 993config ARM_ERRATA_742230 994 bool "ARM errata: DMB operation may be faulty" 995 depends on CPU_V7 && SMP 996 depends on !ARCH_MULTIPLATFORM 997 help 998 This option enables the workaround for the 742230 Cortex-A9 999 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction 1000 between two write operations may not ensure the correct visibility 1001 ordering of the two writes. This workaround sets a specific bit in 1002 the diagnostic register of the Cortex-A9 which causes the DMB 1003 instruction to behave as a DSB, ensuring the correct behaviour of 1004 the two writes. 1005 1006config ARM_ERRATA_742231 1007 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption" 1008 depends on CPU_V7 && SMP 1009 depends on !ARCH_MULTIPLATFORM 1010 help 1011 This option enables the workaround for the 742231 Cortex-A9 1012 (r2p0..r2p2) erratum. Under certain conditions, specific to the 1013 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode, 1014 accessing some data located in the same cache line, may get corrupted 1015 data due to bad handling of the address hazard when the line gets 1016 replaced from one of the CPUs at the same time as another CPU is 1017 accessing it. This workaround sets specific bits in the diagnostic 1018 register of the Cortex-A9 which reduces the linefill issuing 1019 capabilities of the processor. 1020 1021config ARM_ERRATA_643719 1022 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect" 1023 depends on CPU_V7 && SMP 1024 default y 1025 help 1026 This option enables the workaround for the 643719 Cortex-A9 (prior to 1027 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR 1028 register returns zero when it should return one. The workaround 1029 corrects this value, ensuring cache maintenance operations which use 1030 it behave as intended and avoiding data corruption. 1031 1032config ARM_ERRATA_720789 1033 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID" 1034 depends on CPU_V7 1035 help 1036 This option enables the workaround for the 720789 Cortex-A9 (prior to 1037 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the 1038 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS. 1039 As a consequence of this erratum, some TLB entries which should be 1040 invalidated are not, resulting in an incoherency in the system page 1041 tables. The workaround changes the TLB flushing routines to invalidate 1042 entries regardless of the ASID. 1043 1044config ARM_ERRATA_743622 1045 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption" 1046 depends on CPU_V7 1047 depends on !ARCH_MULTIPLATFORM 1048 help 1049 This option enables the workaround for the 743622 Cortex-A9 1050 (r2p*) erratum. Under very rare conditions, a faulty 1051 optimisation in the Cortex-A9 Store Buffer may lead to data 1052 corruption. This workaround sets a specific bit in the diagnostic 1053 register of the Cortex-A9 which disables the Store Buffer 1054 optimisation, preventing the defect from occurring. This has no 1055 visible impact on the overall performance or power consumption of the 1056 processor. 1057 1058config ARM_ERRATA_751472 1059 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation" 1060 depends on CPU_V7 1061 depends on !ARCH_MULTIPLATFORM 1062 help 1063 This option enables the workaround for the 751472 Cortex-A9 (prior 1064 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the 1065 completion of a following broadcasted operation if the second 1066 operation is received by a CPU before the ICIALLUIS has completed, 1067 potentially leading to corrupted entries in the cache or TLB. 1068 1069config ARM_ERRATA_754322 1070 bool "ARM errata: possible faulty MMU translations following an ASID switch" 1071 depends on CPU_V7 1072 help 1073 This option enables the workaround for the 754322 Cortex-A9 (r2p*, 1074 r3p*) erratum. A speculative memory access may cause a page table walk 1075 which starts prior to an ASID switch but completes afterwards. This 1076 can populate the micro-TLB with a stale entry which may be hit with 1077 the new ASID. This workaround places two dsb instructions in the mm 1078 switching code so that no page table walks can cross the ASID switch. 1079 1080config ARM_ERRATA_754327 1081 bool "ARM errata: no automatic Store Buffer drain" 1082 depends on CPU_V7 && SMP 1083 help 1084 This option enables the workaround for the 754327 Cortex-A9 (prior to 1085 r2p0) erratum. The Store Buffer does not have any automatic draining 1086 mechanism and therefore a livelock may occur if an external agent 1087 continuously polls a memory location waiting to observe an update. 1088 This workaround defines cpu_relax() as smp_mb(), preventing correctly 1089 written polling loops from denying visibility of updates to memory. 1090 1091config ARM_ERRATA_364296 1092 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled" 1093 depends on CPU_V6 1094 help 1095 This options enables the workaround for the 364296 ARM1136 1096 r0p2 erratum (possible cache data corruption with 1097 hit-under-miss enabled). It sets the undocumented bit 31 in 1098 the auxiliary control register and the FI bit in the control 1099 register, thus disabling hit-under-miss without putting the 1100 processor into full low interrupt latency mode. ARM11MPCore 1101 is not affected. 1102 1103config ARM_ERRATA_764369 1104 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed" 1105 depends on CPU_V7 && SMP 1106 help 1107 This option enables the workaround for erratum 764369 1108 affecting Cortex-A9 MPCore with two or more processors (all 1109 current revisions). Under certain timing circumstances, a data 1110 cache line maintenance operation by MVA targeting an Inner 1111 Shareable memory region may fail to proceed up to either the 1112 Point of Coherency or to the Point of Unification of the 1113 system. This workaround adds a DSB instruction before the 1114 relevant cache maintenance functions and sets a specific bit 1115 in the diagnostic control register of the SCU. 1116 1117config ARM_ERRATA_775420 1118 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock" 1119 depends on CPU_V7 1120 help 1121 This option enables the workaround for the 775420 Cortex-A9 (r2p2, 1122 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance 1123 operation aborts with MMU exception, it might cause the processor 1124 to deadlock. This workaround puts DSB before executing ISB if 1125 an abort may occur on cache maintenance. 1126 1127config ARM_ERRATA_798181 1128 bool "ARM errata: TLBI/DSB failure on Cortex-A15" 1129 depends on CPU_V7 && SMP 1130 help 1131 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not 1132 adequately shooting down all use of the old entries. This 1133 option enables the Linux kernel workaround for this erratum 1134 which sends an IPI to the CPUs that are running the same ASID 1135 as the one being invalidated. 1136 1137config ARM_ERRATA_773022 1138 bool "ARM errata: incorrect instructions may be executed from loop buffer" 1139 depends on CPU_V7 1140 help 1141 This option enables the workaround for the 773022 Cortex-A15 1142 (up to r0p4) erratum. In certain rare sequences of code, the 1143 loop buffer may deliver incorrect instructions. This 1144 workaround disables the loop buffer to avoid the erratum. 1145 1146config ARM_ERRATA_818325_852422 1147 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption" 1148 depends on CPU_V7 1149 help 1150 This option enables the workaround for: 1151 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM 1152 instruction might deadlock. Fixed in r0p1. 1153 - Cortex-A12 852422: Execution of a sequence of instructions might 1154 lead to either a data corruption or a CPU deadlock. Not fixed in 1155 any Cortex-A12 cores yet. 1156 This workaround for all both errata involves setting bit[12] of the 1157 Feature Register. This bit disables an optimisation applied to a 1158 sequence of 2 instructions that use opposing condition codes. 1159 1160config ARM_ERRATA_821420 1161 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock" 1162 depends on CPU_V7 1163 help 1164 This option enables the workaround for the 821420 Cortex-A12 1165 (all revs) erratum. In very rare timing conditions, a sequence 1166 of VMOV to Core registers instructions, for which the second 1167 one is in the shadow of a branch or abort, can lead to a 1168 deadlock when the VMOV instructions are issued out-of-order. 1169 1170config ARM_ERRATA_825619 1171 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock" 1172 depends on CPU_V7 1173 help 1174 This option enables the workaround for the 825619 Cortex-A12 1175 (all revs) erratum. Within rare timing constraints, executing a 1176 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable 1177 and Device/Strongly-Ordered loads and stores might cause deadlock 1178 1179config ARM_ERRATA_852421 1180 bool "ARM errata: A17: DMB ST might fail to create order between stores" 1181 depends on CPU_V7 1182 help 1183 This option enables the workaround for the 852421 Cortex-A17 1184 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions, 1185 execution of a DMB ST instruction might fail to properly order 1186 stores from GroupA and stores from GroupB. 1187 1188config ARM_ERRATA_852423 1189 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption" 1190 depends on CPU_V7 1191 help 1192 This option enables the workaround for: 1193 - Cortex-A17 852423: Execution of a sequence of instructions might 1194 lead to either a data corruption or a CPU deadlock. Not fixed in 1195 any Cortex-A17 cores yet. 1196 This is identical to Cortex-A12 erratum 852422. It is a separate 1197 config option from the A12 erratum due to the way errata are checked 1198 for and handled. 1199 1200endmenu 1201 1202source "arch/arm/common/Kconfig" 1203 1204menu "Bus support" 1205 1206config ISA 1207 bool 1208 help 1209 Find out whether you have ISA slots on your motherboard. ISA is the 1210 name of a bus system, i.e. the way the CPU talks to the other stuff 1211 inside your box. Other bus systems are PCI, EISA, MicroChannel 1212 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1213 newer boards don't support it. If you have ISA, say Y, otherwise N. 1214 1215# Select ISA DMA controller support 1216config ISA_DMA 1217 bool 1218 select ISA_DMA_API 1219 1220# Select ISA DMA interface 1221config ISA_DMA_API 1222 bool 1223 1224config PCI_NANOENGINE 1225 bool "BSE nanoEngine PCI support" 1226 depends on SA1100_NANOENGINE 1227 help 1228 Enable PCI on the BSE nanoEngine board. 1229 1230config PCI_HOST_ITE8152 1231 bool 1232 depends on PCI && MACH_ARMCORE 1233 default y 1234 select DMABOUNCE 1235 1236endmenu 1237 1238menu "Kernel Features" 1239 1240config HAVE_SMP 1241 bool 1242 help 1243 This option should be selected by machines which have an SMP- 1244 capable CPU. 1245 1246 The only effect of this option is to make the SMP-related 1247 options available to the user for configuration. 1248 1249config SMP 1250 bool "Symmetric Multi-Processing" 1251 depends on CPU_V6K || CPU_V7 1252 depends on GENERIC_CLOCKEVENTS 1253 depends on HAVE_SMP 1254 depends on MMU || ARM_MPU 1255 select IRQ_WORK 1256 help 1257 This enables support for systems with more than one CPU. If you have 1258 a system with only one CPU, say N. If you have a system with more 1259 than one CPU, say Y. 1260 1261 If you say N here, the kernel will run on uni- and multiprocessor 1262 machines, but will use only one CPU of a multiprocessor machine. If 1263 you say Y here, the kernel will run on many, but not all, 1264 uniprocessor machines. On a uniprocessor machine, the kernel 1265 will run faster if you say N here. 1266 1267 See also <file:Documentation/x86/i386/IO-APIC.txt>, 1268 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 1269 <http://tldp.org/HOWTO/SMP-HOWTO.html>. 1270 1271 If you don't know what to do here, say N. 1272 1273config SMP_ON_UP 1274 bool "Allow booting SMP kernel on uniprocessor systems" 1275 depends on SMP && !XIP_KERNEL && MMU 1276 default y 1277 help 1278 SMP kernels contain instructions which fail on non-SMP processors. 1279 Enabling this option allows the kernel to modify itself to make 1280 these instructions safe. Disabling it allows about 1K of space 1281 savings. 1282 1283 If you don't know what to do here, say Y. 1284 1285config ARM_CPU_TOPOLOGY 1286 bool "Support cpu topology definition" 1287 depends on SMP && CPU_V7 1288 default y 1289 help 1290 Support ARM cpu topology definition. The MPIDR register defines 1291 affinity between processors which is then used to describe the cpu 1292 topology of an ARM System. 1293 1294config SCHED_MC 1295 bool "Multi-core scheduler support" 1296 depends on ARM_CPU_TOPOLOGY 1297 help 1298 Multi-core scheduler support improves the CPU scheduler's decision 1299 making when dealing with multi-core CPU chips at a cost of slightly 1300 increased overhead in some places. If unsure say N here. 1301 1302config SCHED_SMT 1303 bool "SMT scheduler support" 1304 depends on ARM_CPU_TOPOLOGY 1305 help 1306 Improves the CPU scheduler's decision making when dealing with 1307 MultiThreading at a cost of slightly increased overhead in some 1308 places. If unsure say N here. 1309 1310config HAVE_ARM_SCU 1311 bool 1312 help 1313 This option enables support for the ARM snoop control unit 1314 1315config HAVE_ARM_ARCH_TIMER 1316 bool "Architected timer support" 1317 depends on CPU_V7 1318 select ARM_ARCH_TIMER 1319 select GENERIC_CLOCKEVENTS 1320 help 1321 This option enables support for the ARM architected timer 1322 1323config HAVE_ARM_TWD 1324 bool 1325 help 1326 This options enables support for the ARM timer and watchdog unit 1327 1328config MCPM 1329 bool "Multi-Cluster Power Management" 1330 depends on CPU_V7 && SMP 1331 help 1332 This option provides the common power management infrastructure 1333 for (multi-)cluster based systems, such as big.LITTLE based 1334 systems. 1335 1336config MCPM_QUAD_CLUSTER 1337 bool 1338 depends on MCPM 1339 help 1340 To avoid wasting resources unnecessarily, MCPM only supports up 1341 to 2 clusters by default. 1342 Platforms with 3 or 4 clusters that use MCPM must select this 1343 option to allow the additional clusters to be managed. 1344 1345config BIG_LITTLE 1346 bool "big.LITTLE support (Experimental)" 1347 depends on CPU_V7 && SMP 1348 select MCPM 1349 help 1350 This option enables support selections for the big.LITTLE 1351 system architecture. 1352 1353config BL_SWITCHER 1354 bool "big.LITTLE switcher support" 1355 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC 1356 select CPU_PM 1357 help 1358 The big.LITTLE "switcher" provides the core functionality to 1359 transparently handle transition between a cluster of A15's 1360 and a cluster of A7's in a big.LITTLE system. 1361 1362config BL_SWITCHER_DUMMY_IF 1363 tristate "Simple big.LITTLE switcher user interface" 1364 depends on BL_SWITCHER && DEBUG_KERNEL 1365 help 1366 This is a simple and dummy char dev interface to control 1367 the big.LITTLE switcher core code. It is meant for 1368 debugging purposes only. 1369 1370choice 1371 prompt "Memory split" 1372 depends on MMU 1373 default VMSPLIT_3G 1374 help 1375 Select the desired split between kernel and user memory. 1376 1377 If you are not absolutely sure what you are doing, leave this 1378 option alone! 1379 1380 config VMSPLIT_3G 1381 bool "3G/1G user/kernel split" 1382 config VMSPLIT_3G_OPT 1383 depends on !ARM_LPAE 1384 bool "3G/1G user/kernel split (for full 1G low memory)" 1385 config VMSPLIT_2G 1386 bool "2G/2G user/kernel split" 1387 config VMSPLIT_1G 1388 bool "1G/3G user/kernel split" 1389endchoice 1390 1391config PAGE_OFFSET 1392 hex 1393 default PHYS_OFFSET if !MMU 1394 default 0x40000000 if VMSPLIT_1G 1395 default 0x80000000 if VMSPLIT_2G 1396 default 0xB0000000 if VMSPLIT_3G_OPT 1397 default 0xC0000000 1398 1399config NR_CPUS 1400 int "Maximum number of CPUs (2-32)" 1401 range 2 32 1402 depends on SMP 1403 default "4" 1404 1405config HOTPLUG_CPU 1406 bool "Support for hot-pluggable CPUs" 1407 depends on SMP 1408 select GENERIC_IRQ_MIGRATION 1409 help 1410 Say Y here to experiment with turning CPUs off and on. CPUs 1411 can be controlled through /sys/devices/system/cpu. 1412 1413config ARM_PSCI 1414 bool "Support for the ARM Power State Coordination Interface (PSCI)" 1415 depends on HAVE_ARM_SMCCC 1416 select ARM_PSCI_FW 1417 help 1418 Say Y here if you want Linux to communicate with system firmware 1419 implementing the PSCI specification for CPU-centric power 1420 management operations described in ARM document number ARM DEN 1421 0022A ("Power State Coordination Interface System Software on 1422 ARM processors"). 1423 1424# The GPIO number here must be sorted by descending number. In case of 1425# a multiplatform kernel, we just want the highest value required by the 1426# selected platforms. 1427config ARCH_NR_GPIO 1428 int 1429 default 2048 if ARCH_SOCFPGA 1430 default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \ 1431 ARCH_ZYNQ 1432 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \ 1433 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210 1434 default 416 if ARCH_SUNXI 1435 default 392 if ARCH_U8500 1436 default 352 if ARCH_VT8500 1437 default 288 if ARCH_ROCKCHIP 1438 default 264 if MACH_H4700 1439 default 0 1440 help 1441 Maximum number of GPIOs in the system. 1442 1443 If unsure, leave the default value. 1444 1445config HZ_FIXED 1446 int 1447 default 200 if ARCH_EBSA110 1448 default 128 if SOC_AT91RM9200 1449 default 0 1450 1451choice 1452 depends on HZ_FIXED = 0 1453 prompt "Timer frequency" 1454 1455config HZ_100 1456 bool "100 Hz" 1457 1458config HZ_200 1459 bool "200 Hz" 1460 1461config HZ_250 1462 bool "250 Hz" 1463 1464config HZ_300 1465 bool "300 Hz" 1466 1467config HZ_500 1468 bool "500 Hz" 1469 1470config HZ_1000 1471 bool "1000 Hz" 1472 1473endchoice 1474 1475config HZ 1476 int 1477 default HZ_FIXED if HZ_FIXED != 0 1478 default 100 if HZ_100 1479 default 200 if HZ_200 1480 default 250 if HZ_250 1481 default 300 if HZ_300 1482 default 500 if HZ_500 1483 default 1000 1484 1485config SCHED_HRTICK 1486 def_bool HIGH_RES_TIMERS 1487 1488config THUMB2_KERNEL 1489 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY 1490 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K 1491 default y if CPU_THUMBONLY 1492 select ARM_UNWIND 1493 help 1494 By enabling this option, the kernel will be compiled in 1495 Thumb-2 mode. 1496 1497 If unsure, say N. 1498 1499config THUMB2_AVOID_R_ARM_THM_JUMP11 1500 bool "Work around buggy Thumb-2 short branch relocations in gas" 1501 depends on THUMB2_KERNEL && MODULES 1502 default y 1503 help 1504 Various binutils versions can resolve Thumb-2 branches to 1505 locally-defined, preemptible global symbols as short-range "b.n" 1506 branch instructions. 1507 1508 This is a problem, because there's no guarantee the final 1509 destination of the symbol, or any candidate locations for a 1510 trampoline, are within range of the branch. For this reason, the 1511 kernel does not support fixing up the R_ARM_THM_JUMP11 (102) 1512 relocation in modules at all, and it makes little sense to add 1513 support. 1514 1515 The symptom is that the kernel fails with an "unsupported 1516 relocation" error when loading some modules. 1517 1518 Until fixed tools are available, passing 1519 -fno-optimize-sibling-calls to gcc should prevent gcc generating 1520 code which hits this problem, at the cost of a bit of extra runtime 1521 stack usage in some cases. 1522 1523 The problem is described in more detail at: 1524 https://bugs.launchpad.net/binutils-linaro/+bug/725126 1525 1526 Only Thumb-2 kernels are affected. 1527 1528 Unless you are sure your tools don't have this problem, say Y. 1529 1530config ARM_PATCH_IDIV 1531 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()" 1532 depends on CPU_32v7 && !XIP_KERNEL 1533 default y 1534 help 1535 The ARM compiler inserts calls to __aeabi_idiv() and 1536 __aeabi_uidiv() when it needs to perform division on signed 1537 and unsigned integers. Some v7 CPUs have support for the sdiv 1538 and udiv instructions that can be used to implement those 1539 functions. 1540 1541 Enabling this option allows the kernel to modify itself to 1542 replace the first two instructions of these library functions 1543 with the sdiv or udiv plus "bx lr" instructions when the CPU 1544 it is running on supports them. Typically this will be faster 1545 and less power intensive than running the original library 1546 code to do integer division. 1547 1548config AEABI 1549 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && !CPU_V7M && !CPU_V6 && !CPU_V6K 1550 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K 1551 help 1552 This option allows for the kernel to be compiled using the latest 1553 ARM ABI (aka EABI). This is only useful if you are using a user 1554 space environment that is also compiled with EABI. 1555 1556 Since there are major incompatibilities between the legacy ABI and 1557 EABI, especially with regard to structure member alignment, this 1558 option also changes the kernel syscall calling convention to 1559 disambiguate both ABIs and allow for backward compatibility support 1560 (selected with CONFIG_OABI_COMPAT). 1561 1562 To use this you need GCC version 4.0.0 or later. 1563 1564config OABI_COMPAT 1565 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)" 1566 depends on AEABI && !THUMB2_KERNEL 1567 help 1568 This option preserves the old syscall interface along with the 1569 new (ARM EABI) one. It also provides a compatibility layer to 1570 intercept syscalls that have structure arguments which layout 1571 in memory differs between the legacy ABI and the new ARM EABI 1572 (only for non "thumb" binaries). This option adds a tiny 1573 overhead to all syscalls and produces a slightly larger kernel. 1574 1575 The seccomp filter system will not be available when this is 1576 selected, since there is no way yet to sensibly distinguish 1577 between calling conventions during filtering. 1578 1579 If you know you'll be using only pure EABI user space then you 1580 can say N here. If this option is not selected and you attempt 1581 to execute a legacy ABI binary then the result will be 1582 UNPREDICTABLE (in fact it can be predicted that it won't work 1583 at all). If in doubt say N. 1584 1585config ARCH_HAS_HOLES_MEMORYMODEL 1586 bool 1587 1588config ARCH_SPARSEMEM_ENABLE 1589 bool 1590 1591config ARCH_SPARSEMEM_DEFAULT 1592 def_bool ARCH_SPARSEMEM_ENABLE 1593 1594config ARCH_SELECT_MEMORY_MODEL 1595 def_bool ARCH_SPARSEMEM_ENABLE 1596 1597config HAVE_ARCH_PFN_VALID 1598 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM 1599 1600config HAVE_GENERIC_GUP 1601 def_bool y 1602 depends on ARM_LPAE 1603 1604config HIGHMEM 1605 bool "High Memory Support" 1606 depends on MMU 1607 help 1608 The address space of ARM processors is only 4 Gigabytes large 1609 and it has to accommodate user address space, kernel address 1610 space as well as some memory mapped IO. That means that, if you 1611 have a large amount of physical memory and/or IO, not all of the 1612 memory can be "permanently mapped" by the kernel. The physical 1613 memory that is not permanently mapped is called "high memory". 1614 1615 Depending on the selected kernel/user memory split, minimum 1616 vmalloc space and actual amount of RAM, you may not need this 1617 option which should result in a slightly faster kernel. 1618 1619 If unsure, say n. 1620 1621config HIGHPTE 1622 bool "Allocate 2nd-level pagetables from highmem" if EXPERT 1623 depends on HIGHMEM 1624 default y 1625 help 1626 The VM uses one page of physical memory for each page table. 1627 For systems with a lot of processes, this can use a lot of 1628 precious low memory, eventually leading to low memory being 1629 consumed by page tables. Setting this option will allow 1630 user-space 2nd level page tables to reside in high memory. 1631 1632config CPU_SW_DOMAIN_PAN 1633 bool "Enable use of CPU domains to implement privileged no-access" 1634 depends on MMU && !ARM_LPAE 1635 default y 1636 help 1637 Increase kernel security by ensuring that normal kernel accesses 1638 are unable to access userspace addresses. This can help prevent 1639 use-after-free bugs becoming an exploitable privilege escalation 1640 by ensuring that magic values (such as LIST_POISON) will always 1641 fault when dereferenced. 1642 1643 CPUs with low-vector mappings use a best-efforts implementation. 1644 Their lower 1MB needs to remain accessible for the vectors, but 1645 the remainder of userspace will become appropriately inaccessible. 1646 1647config HW_PERF_EVENTS 1648 def_bool y 1649 depends on ARM_PMU 1650 1651config SYS_SUPPORTS_HUGETLBFS 1652 def_bool y 1653 depends on ARM_LPAE 1654 1655config HAVE_ARCH_TRANSPARENT_HUGEPAGE 1656 def_bool y 1657 depends on ARM_LPAE 1658 1659config ARCH_WANT_GENERAL_HUGETLB 1660 def_bool y 1661 1662config ARM_MODULE_PLTS 1663 bool "Use PLTs to allow module memory to spill over into vmalloc area" 1664 depends on MODULES 1665 default y 1666 help 1667 Allocate PLTs when loading modules so that jumps and calls whose 1668 targets are too far away for their relative offsets to be encoded 1669 in the instructions themselves can be bounced via veneers in the 1670 module's PLT. This allows modules to be allocated in the generic 1671 vmalloc area after the dedicated module memory area has been 1672 exhausted. The modules will use slightly more memory, but after 1673 rounding up to page size, the actual memory footprint is usually 1674 the same. 1675 1676 Disabling this is usually safe for small single-platform 1677 configurations. If unsure, say y. 1678 1679config FORCE_MAX_ZONEORDER 1680 int "Maximum zone order" 1681 default "12" if SOC_AM33XX 1682 default "9" if SA1111 || ARCH_EFM32 1683 default "11" 1684 help 1685 The kernel memory allocator divides physically contiguous memory 1686 blocks into "zones", where each zone is a power of two number of 1687 pages. This option selects the largest power of two that the kernel 1688 keeps in the memory allocator. If you need to allocate very large 1689 blocks of physically contiguous memory, then you may need to 1690 increase this value. 1691 1692 This config option is actually maximum order plus one. For example, 1693 a value of 11 means that the largest free memory block is 2^10 pages. 1694 1695config ALIGNMENT_TRAP 1696 bool 1697 depends on CPU_CP15_MMU 1698 default y if !ARCH_EBSA110 1699 select HAVE_PROC_CPU if PROC_FS 1700 help 1701 ARM processors cannot fetch/store information which is not 1702 naturally aligned on the bus, i.e., a 4 byte fetch must start at an 1703 address divisible by 4. On 32-bit ARM processors, these non-aligned 1704 fetch/store instructions will be emulated in software if you say 1705 here, which has a severe performance impact. This is necessary for 1706 correct operation of some network protocols. With an IP-only 1707 configuration it is safe to say N, otherwise say Y. 1708 1709config UACCESS_WITH_MEMCPY 1710 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()" 1711 depends on MMU 1712 default y if CPU_FEROCEON 1713 help 1714 Implement faster copy_to_user and clear_user methods for CPU 1715 cores where a 8-word STM instruction give significantly higher 1716 memory write throughput than a sequence of individual 32bit stores. 1717 1718 A possible side effect is a slight increase in scheduling latency 1719 between threads sharing the same address space if they invoke 1720 such copy operations with large buffers. 1721 1722 However, if the CPU data cache is using a write-allocate mode, 1723 this option is unlikely to provide any performance gain. 1724 1725config SECCOMP 1726 bool 1727 prompt "Enable seccomp to safely compute untrusted bytecode" 1728 ---help--- 1729 This kernel feature is useful for number crunching applications 1730 that may need to compute untrusted bytecode during their 1731 execution. By using pipes or other transports made available to 1732 the process as file descriptors supporting the read/write 1733 syscalls, it's possible to isolate those applications in 1734 their own address space using seccomp. Once seccomp is 1735 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1736 and the task is only allowed to execute a few safe syscalls 1737 defined by each seccomp mode. 1738 1739config PARAVIRT 1740 bool "Enable paravirtualization code" 1741 help 1742 This changes the kernel so it can modify itself when it is run 1743 under a hypervisor, potentially improving performance significantly 1744 over full virtualization. 1745 1746config PARAVIRT_TIME_ACCOUNTING 1747 bool "Paravirtual steal time accounting" 1748 select PARAVIRT 1749 help 1750 Select this option to enable fine granularity task steal time 1751 accounting. Time spent executing other tasks in parallel with 1752 the current vCPU is discounted from the vCPU power. To account for 1753 that, there can be a small performance impact. 1754 1755 If in doubt, say N here. 1756 1757config XEN_DOM0 1758 def_bool y 1759 depends on XEN 1760 1761config XEN 1762 bool "Xen guest support on ARM" 1763 depends on ARM && AEABI && OF 1764 depends on CPU_V7 && !CPU_V6 1765 depends on !GENERIC_ATOMIC64 1766 depends on MMU 1767 select ARCH_DMA_ADDR_T_64BIT 1768 select ARM_PSCI 1769 select SWIOTLB 1770 select SWIOTLB_XEN 1771 select PARAVIRT 1772 help 1773 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM. 1774 1775config STACKPROTECTOR_PER_TASK 1776 bool "Use a unique stack canary value for each task" 1777 depends on GCC_PLUGINS && STACKPROTECTOR && SMP && !XIP_DEFLATED_DATA 1778 select GCC_PLUGIN_ARM_SSP_PER_TASK 1779 default y 1780 help 1781 Due to the fact that GCC uses an ordinary symbol reference from 1782 which to load the value of the stack canary, this value can only 1783 change at reboot time on SMP systems, and all tasks running in the 1784 kernel's address space are forced to use the same canary value for 1785 the entire duration that the system is up. 1786 1787 Enable this option to switch to a different method that uses a 1788 different canary value for each task. 1789 1790endmenu 1791 1792menu "Boot options" 1793 1794config USE_OF 1795 bool "Flattened Device Tree support" 1796 select IRQ_DOMAIN 1797 select OF 1798 help 1799 Include support for flattened device tree machine descriptions. 1800 1801config ATAGS 1802 bool "Support for the traditional ATAGS boot data passing" if USE_OF 1803 default y 1804 help 1805 This is the traditional way of passing data to the kernel at boot 1806 time. If you are solely relying on the flattened device tree (or 1807 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option 1808 to remove ATAGS support from your kernel binary. If unsure, 1809 leave this to y. 1810 1811config DEPRECATED_PARAM_STRUCT 1812 bool "Provide old way to pass kernel parameters" 1813 depends on ATAGS 1814 help 1815 This was deprecated in 2001 and announced to live on for 5 years. 1816 Some old boot loaders still use this way. 1817 1818# Compressed boot loader in ROM. Yes, we really want to ask about 1819# TEXT and BSS so we preserve their values in the config files. 1820config ZBOOT_ROM_TEXT 1821 hex "Compressed ROM boot loader base address" 1822 default "0" 1823 help 1824 The physical address at which the ROM-able zImage is to be 1825 placed in the target. Platforms which normally make use of 1826 ROM-able zImage formats normally set this to a suitable 1827 value in their defconfig file. 1828 1829 If ZBOOT_ROM is not enabled, this has no effect. 1830 1831config ZBOOT_ROM_BSS 1832 hex "Compressed ROM boot loader BSS address" 1833 default "0" 1834 help 1835 The base address of an area of read/write memory in the target 1836 for the ROM-able zImage which must be available while the 1837 decompressor is running. It must be large enough to hold the 1838 entire decompressed kernel plus an additional 128 KiB. 1839 Platforms which normally make use of ROM-able zImage formats 1840 normally set this to a suitable value in their defconfig file. 1841 1842 If ZBOOT_ROM is not enabled, this has no effect. 1843 1844config ZBOOT_ROM 1845 bool "Compressed boot loader in ROM/flash" 1846 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS 1847 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR 1848 help 1849 Say Y here if you intend to execute your compressed kernel image 1850 (zImage) directly from ROM or flash. If unsure, say N. 1851 1852config ARM_APPENDED_DTB 1853 bool "Use appended device tree blob to zImage (EXPERIMENTAL)" 1854 depends on OF 1855 help 1856 With this option, the boot code will look for a device tree binary 1857 (DTB) appended to zImage 1858 (e.g. cat zImage <filename>.dtb > zImage_w_dtb). 1859 1860 This is meant as a backward compatibility convenience for those 1861 systems with a bootloader that can't be upgraded to accommodate 1862 the documented boot protocol using a device tree. 1863 1864 Beware that there is very little in terms of protection against 1865 this option being confused by leftover garbage in memory that might 1866 look like a DTB header after a reboot if no actual DTB is appended 1867 to zImage. Do not leave this option active in a production kernel 1868 if you don't intend to always append a DTB. Proper passing of the 1869 location into r2 of a bootloader provided DTB is always preferable 1870 to this option. 1871 1872config ARM_ATAG_DTB_COMPAT 1873 bool "Supplement the appended DTB with traditional ATAG information" 1874 depends on ARM_APPENDED_DTB 1875 help 1876 Some old bootloaders can't be updated to a DTB capable one, yet 1877 they provide ATAGs with memory configuration, the ramdisk address, 1878 the kernel cmdline string, etc. Such information is dynamically 1879 provided by the bootloader and can't always be stored in a static 1880 DTB. To allow a device tree enabled kernel to be used with such 1881 bootloaders, this option allows zImage to extract the information 1882 from the ATAG list and store it at run time into the appended DTB. 1883 1884choice 1885 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT 1886 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1887 1888config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER 1889 bool "Use bootloader kernel arguments if available" 1890 help 1891 Uses the command-line options passed by the boot loader instead of 1892 the device tree bootargs property. If the boot loader doesn't provide 1893 any, the device tree bootargs property will be used. 1894 1895config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND 1896 bool "Extend with bootloader kernel arguments" 1897 help 1898 The command-line arguments provided by the boot loader will be 1899 appended to the the device tree bootargs property. 1900 1901endchoice 1902 1903config CMDLINE 1904 string "Default kernel command string" 1905 default "" 1906 help 1907 On some architectures (EBSA110 and CATS), there is currently no way 1908 for the boot loader to pass arguments to the kernel. For these 1909 architectures, you should supply some command-line options at build 1910 time by entering them here. As a minimum, you should specify the 1911 memory size and the root device (e.g., mem=64M root=/dev/nfs). 1912 1913choice 1914 prompt "Kernel command line type" if CMDLINE != "" 1915 default CMDLINE_FROM_BOOTLOADER 1916 depends on ATAGS 1917 1918config CMDLINE_FROM_BOOTLOADER 1919 bool "Use bootloader kernel arguments if available" 1920 help 1921 Uses the command-line options passed by the boot loader. If 1922 the boot loader doesn't provide any, the default kernel command 1923 string provided in CMDLINE will be used. 1924 1925config CMDLINE_EXTEND 1926 bool "Extend bootloader kernel arguments" 1927 help 1928 The command-line arguments provided by the boot loader will be 1929 appended to the default kernel command string. 1930 1931config CMDLINE_FORCE 1932 bool "Always use the default kernel command string" 1933 help 1934 Always use the default kernel command string, even if the boot 1935 loader passes other arguments to the kernel. 1936 This is useful if you cannot or don't want to change the 1937 command-line options your boot loader passes to the kernel. 1938endchoice 1939 1940config XIP_KERNEL 1941 bool "Kernel Execute-In-Place from ROM" 1942 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM 1943 help 1944 Execute-In-Place allows the kernel to run from non-volatile storage 1945 directly addressable by the CPU, such as NOR flash. This saves RAM 1946 space since the text section of the kernel is not loaded from flash 1947 to RAM. Read-write sections, such as the data section and stack, 1948 are still copied to RAM. The XIP kernel is not compressed since 1949 it has to run directly from flash, so it will take more space to 1950 store it. The flash address used to link the kernel object files, 1951 and for storing it, is configuration dependent. Therefore, if you 1952 say Y here, you must know the proper physical address where to 1953 store the kernel image depending on your own flash memory usage. 1954 1955 Also note that the make target becomes "make xipImage" rather than 1956 "make zImage" or "make Image". The final kernel binary to put in 1957 ROM memory will be arch/arm/boot/xipImage. 1958 1959 If unsure, say N. 1960 1961config XIP_PHYS_ADDR 1962 hex "XIP Kernel Physical Location" 1963 depends on XIP_KERNEL 1964 default "0x00080000" 1965 help 1966 This is the physical address in your flash memory the kernel will 1967 be linked for and stored to. This address is dependent on your 1968 own flash usage. 1969 1970config XIP_DEFLATED_DATA 1971 bool "Store kernel .data section compressed in ROM" 1972 depends on XIP_KERNEL 1973 select ZLIB_INFLATE 1974 help 1975 Before the kernel is actually executed, its .data section has to be 1976 copied to RAM from ROM. This option allows for storing that data 1977 in compressed form and decompressed to RAM rather than merely being 1978 copied, saving some precious ROM space. A possible drawback is a 1979 slightly longer boot delay. 1980 1981config KEXEC 1982 bool "Kexec system call (EXPERIMENTAL)" 1983 depends on (!SMP || PM_SLEEP_SMP) 1984 depends on !CPU_V7M 1985 select KEXEC_CORE 1986 help 1987 kexec is a system call that implements the ability to shutdown your 1988 current kernel, and to start another kernel. It is like a reboot 1989 but it is independent of the system firmware. And like a reboot 1990 you can start any kernel with it, not just Linux. 1991 1992 It is an ongoing process to be certain the hardware in a machine 1993 is properly shutdown, so do not be surprised if this code does not 1994 initially work for you. 1995 1996config ATAGS_PROC 1997 bool "Export atags in procfs" 1998 depends on ATAGS && KEXEC 1999 default y 2000 help 2001 Should the atags used to boot the kernel be exported in an "atags" 2002 file in procfs. Useful with kexec. 2003 2004config CRASH_DUMP 2005 bool "Build kdump crash kernel (EXPERIMENTAL)" 2006 help 2007 Generate crash dump after being started by kexec. This should 2008 be normally only set in special crash dump kernels which are 2009 loaded in the main kernel with kexec-tools into a specially 2010 reserved region and then later executed after a crash by 2011 kdump/kexec. The crash dump kernel must be compiled to a 2012 memory address not used by the main kernel 2013 2014 For more details see Documentation/kdump/kdump.txt 2015 2016config AUTO_ZRELADDR 2017 bool "Auto calculation of the decompressed kernel image address" 2018 help 2019 ZRELADDR is the physical address where the decompressed kernel 2020 image will be placed. If AUTO_ZRELADDR is selected, the address 2021 will be determined at run-time by masking the current IP with 2022 0xf8000000. This assumes the zImage being placed in the first 128MB 2023 from start of memory. 2024 2025config EFI_STUB 2026 bool 2027 2028config EFI 2029 bool "UEFI runtime support" 2030 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL 2031 select UCS2_STRING 2032 select EFI_PARAMS_FROM_FDT 2033 select EFI_STUB 2034 select EFI_ARMSTUB 2035 select EFI_RUNTIME_WRAPPERS 2036 ---help--- 2037 This option provides support for runtime services provided 2038 by UEFI firmware (such as non-volatile variables, realtime 2039 clock, and platform reset). A UEFI stub is also provided to 2040 allow the kernel to be booted as an EFI application. This 2041 is only useful for kernels that may run on systems that have 2042 UEFI firmware. 2043 2044config DMI 2045 bool "Enable support for SMBIOS (DMI) tables" 2046 depends on EFI 2047 default y 2048 help 2049 This enables SMBIOS/DMI feature for systems. 2050 2051 This option is only useful on systems that have UEFI firmware. 2052 However, even with this option, the resultant kernel should 2053 continue to boot on existing non-UEFI platforms. 2054 2055 NOTE: This does *NOT* enable or encourage the use of DMI quirks, 2056 i.e., the the practice of identifying the platform via DMI to 2057 decide whether certain workarounds for buggy hardware and/or 2058 firmware need to be enabled. This would require the DMI subsystem 2059 to be enabled much earlier than we do on ARM, which is non-trivial. 2060 2061endmenu 2062 2063menu "CPU Power Management" 2064 2065source "drivers/cpufreq/Kconfig" 2066 2067source "drivers/cpuidle/Kconfig" 2068 2069endmenu 2070 2071menu "Floating point emulation" 2072 2073comment "At least one emulation must be selected" 2074 2075config FPE_NWFPE 2076 bool "NWFPE math emulation" 2077 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL 2078 ---help--- 2079 Say Y to include the NWFPE floating point emulator in the kernel. 2080 This is necessary to run most binaries. Linux does not currently 2081 support floating point hardware so you need to say Y here even if 2082 your machine has an FPA or floating point co-processor podule. 2083 2084 You may say N here if you are going to load the Acorn FPEmulator 2085 early in the bootup. 2086 2087config FPE_NWFPE_XP 2088 bool "Support extended precision" 2089 depends on FPE_NWFPE 2090 help 2091 Say Y to include 80-bit support in the kernel floating-point 2092 emulator. Otherwise, only 32 and 64-bit support is compiled in. 2093 Note that gcc does not generate 80-bit operations by default, 2094 so in most cases this option only enlarges the size of the 2095 floating point emulator without any good reason. 2096 2097 You almost surely want to say N here. 2098 2099config FPE_FASTFPE 2100 bool "FastFPE math emulation (EXPERIMENTAL)" 2101 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 2102 ---help--- 2103 Say Y here to include the FAST floating point emulator in the kernel. 2104 This is an experimental much faster emulator which now also has full 2105 precision for the mantissa. It does not support any exceptions. 2106 It is very simple, and approximately 3-6 times faster than NWFPE. 2107 2108 It should be sufficient for most programs. It may be not suitable 2109 for scientific calculations, but you have to check this for yourself. 2110 If you do not feel you need a faster FP emulation you should better 2111 choose NWFPE. 2112 2113config VFP 2114 bool "VFP-format floating point maths" 2115 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON 2116 help 2117 Say Y to include VFP support code in the kernel. This is needed 2118 if your hardware includes a VFP unit. 2119 2120 Please see <file:Documentation/arm/VFP/release-notes.txt> for 2121 release notes and additional status information. 2122 2123 Say N if your target does not have VFP hardware. 2124 2125config VFPv3 2126 bool 2127 depends on VFP 2128 default y if CPU_V7 2129 2130config NEON 2131 bool "Advanced SIMD (NEON) Extension support" 2132 depends on VFPv3 && CPU_V7 2133 help 2134 Say Y to include support code for NEON, the ARMv7 Advanced SIMD 2135 Extension. 2136 2137config KERNEL_MODE_NEON 2138 bool "Support for NEON in kernel mode" 2139 depends on NEON && AEABI 2140 help 2141 Say Y to include support for NEON in kernel mode. 2142 2143endmenu 2144 2145menu "Power management options" 2146 2147source "kernel/power/Kconfig" 2148 2149config ARCH_SUSPEND_POSSIBLE 2150 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \ 2151 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK 2152 def_bool y 2153 2154config ARM_CPU_SUSPEND 2155 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW 2156 depends on ARCH_SUSPEND_POSSIBLE 2157 2158config ARCH_HIBERNATION_POSSIBLE 2159 bool 2160 depends on MMU 2161 default y if ARCH_SUSPEND_POSSIBLE 2162 2163endmenu 2164 2165source "drivers/firmware/Kconfig" 2166 2167if CRYPTO 2168source "arch/arm/crypto/Kconfig" 2169endif 2170 2171source "arch/arm/kvm/Kconfig" 2172