1comment "Processor Type" 2 3# Select CPU types depending on the architecture selected. This selects 4# which CPUs we support in the kernel image, and the compiler instruction 5# optimiser behaviour. 6 7# ARM610 8config CPU_ARM610 9 bool "Support ARM610 processor" if ARCH_RPC 10 select CPU_32v3 11 select CPU_CACHE_V3 12 select CPU_CACHE_VIVT 13 select CPU_CP15_MMU 14 select CPU_COPY_V3 if MMU 15 select CPU_TLB_V3 if MMU 16 select CPU_PABRT_LEGACY 17 help 18 The ARM610 is the successor to the ARM3 processor 19 and was produced by VLSI Technology Inc. 20 21 Say Y if you want support for the ARM610 processor. 22 Otherwise, say N. 23 24# ARM7TDMI 25config CPU_ARM7TDMI 26 bool "Support ARM7TDMI processor" 27 depends on !MMU 28 select CPU_32v4T 29 select CPU_ABRT_LV4T 30 select CPU_PABRT_LEGACY 31 select CPU_CACHE_V4 32 help 33 A 32-bit RISC microprocessor based on the ARM7 processor core 34 which has no memory control unit and cache. 35 36 Say Y if you want support for the ARM7TDMI processor. 37 Otherwise, say N. 38 39# ARM710 40config CPU_ARM710 41 bool "Support ARM710 processor" if ARCH_RPC 42 select CPU_32v3 43 select CPU_CACHE_V3 44 select CPU_CACHE_VIVT 45 select CPU_CP15_MMU 46 select CPU_COPY_V3 if MMU 47 select CPU_TLB_V3 if MMU 48 select CPU_PABRT_LEGACY 49 help 50 A 32-bit RISC microprocessor based on the ARM7 processor core 51 designed by Advanced RISC Machines Ltd. The ARM710 is the 52 successor to the ARM610 processor. It was released in 53 July 1994 by VLSI Technology Inc. 54 55 Say Y if you want support for the ARM710 processor. 56 Otherwise, say N. 57 58# ARM720T 59config CPU_ARM720T 60 bool "Support ARM720T processor" if ARCH_INTEGRATOR 61 select CPU_32v4T 62 select CPU_ABRT_LV4T 63 select CPU_PABRT_LEGACY 64 select CPU_CACHE_V4 65 select CPU_CACHE_VIVT 66 select CPU_CP15_MMU 67 select CPU_COPY_V4WT if MMU 68 select CPU_TLB_V4WT if MMU 69 help 70 A 32-bit RISC processor with 8kByte Cache, Write Buffer and 71 MMU built around an ARM7TDMI core. 72 73 Say Y if you want support for the ARM720T processor. 74 Otherwise, say N. 75 76# ARM740T 77config CPU_ARM740T 78 bool "Support ARM740T processor" if ARCH_INTEGRATOR 79 depends on !MMU 80 select CPU_32v4T 81 select CPU_ABRT_LV4T 82 select CPU_PABRT_LEGACY 83 select CPU_CACHE_V3 # although the core is v4t 84 select CPU_CP15_MPU 85 help 86 A 32-bit RISC processor with 8KB cache or 4KB variants, 87 write buffer and MPU(Protection Unit) built around 88 an ARM7TDMI core. 89 90 Say Y if you want support for the ARM740T processor. 91 Otherwise, say N. 92 93# ARM9TDMI 94config CPU_ARM9TDMI 95 bool "Support ARM9TDMI processor" 96 depends on !MMU 97 select CPU_32v4T 98 select CPU_ABRT_NOMMU 99 select CPU_PABRT_LEGACY 100 select CPU_CACHE_V4 101 help 102 A 32-bit RISC microprocessor based on the ARM9 processor core 103 which has no memory control unit and cache. 104 105 Say Y if you want support for the ARM9TDMI processor. 106 Otherwise, say N. 107 108# ARM920T 109config CPU_ARM920T 110 bool "Support ARM920T processor" if ARCH_INTEGRATOR 111 select CPU_32v4T 112 select CPU_ABRT_EV4T 113 select CPU_PABRT_LEGACY 114 select CPU_CACHE_V4WT 115 select CPU_CACHE_VIVT 116 select CPU_CP15_MMU 117 select CPU_COPY_V4WB if MMU 118 select CPU_TLB_V4WBI if MMU 119 help 120 The ARM920T is licensed to be produced by numerous vendors, 121 and is used in the Cirrus EP93xx and the Samsung S3C2410. 122 123 Say Y if you want support for the ARM920T processor. 124 Otherwise, say N. 125 126# ARM922T 127config CPU_ARM922T 128 bool "Support ARM922T processor" if ARCH_INTEGRATOR 129 select CPU_32v4T 130 select CPU_ABRT_EV4T 131 select CPU_PABRT_LEGACY 132 select CPU_CACHE_V4WT 133 select CPU_CACHE_VIVT 134 select CPU_CP15_MMU 135 select CPU_COPY_V4WB if MMU 136 select CPU_TLB_V4WBI if MMU 137 help 138 The ARM922T is a version of the ARM920T, but with smaller 139 instruction and data caches. It is used in Altera's 140 Excalibur XA device family and Micrel's KS8695 Centaur. 141 142 Say Y if you want support for the ARM922T processor. 143 Otherwise, say N. 144 145# ARM925T 146config CPU_ARM925T 147 bool "Support ARM925T processor" if ARCH_OMAP1 148 select CPU_32v4T 149 select CPU_ABRT_EV4T 150 select CPU_PABRT_LEGACY 151 select CPU_CACHE_V4WT 152 select CPU_CACHE_VIVT 153 select CPU_CP15_MMU 154 select CPU_COPY_V4WB if MMU 155 select CPU_TLB_V4WBI if MMU 156 help 157 The ARM925T is a mix between the ARM920T and ARM926T, but with 158 different instruction and data caches. It is used in TI's OMAP 159 device family. 160 161 Say Y if you want support for the ARM925T processor. 162 Otherwise, say N. 163 164# ARM926T 165config CPU_ARM926T 166 bool "Support ARM926T processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB 167 select CPU_32v5 168 select CPU_ABRT_EV5TJ 169 select CPU_PABRT_LEGACY 170 select CPU_CACHE_VIVT 171 select CPU_CP15_MMU 172 select CPU_COPY_V4WB if MMU 173 select CPU_TLB_V4WBI if MMU 174 help 175 This is a variant of the ARM920. It has slightly different 176 instruction sequences for cache and TLB operations. Curiously, 177 there is no documentation on it at the ARM corporate website. 178 179 Say Y if you want support for the ARM926T processor. 180 Otherwise, say N. 181 182# FA526 183config CPU_FA526 184 bool 185 select CPU_32v4 186 select CPU_ABRT_EV4 187 select CPU_PABRT_LEGACY 188 select CPU_CACHE_VIVT 189 select CPU_CP15_MMU 190 select CPU_CACHE_FA 191 select CPU_COPY_FA if MMU 192 select CPU_TLB_FA if MMU 193 help 194 The FA526 is a version of the ARMv4 compatible processor with 195 Branch Target Buffer, Unified TLB and cache line size 16. 196 197 Say Y if you want support for the FA526 processor. 198 Otherwise, say N. 199 200# ARM940T 201config CPU_ARM940T 202 bool "Support ARM940T processor" if ARCH_INTEGRATOR 203 depends on !MMU 204 select CPU_32v4T 205 select CPU_ABRT_NOMMU 206 select CPU_PABRT_LEGACY 207 select CPU_CACHE_VIVT 208 select CPU_CP15_MPU 209 help 210 ARM940T is a member of the ARM9TDMI family of general- 211 purpose microprocessors with MPU and separate 4KB 212 instruction and 4KB data cases, each with a 4-word line 213 length. 214 215 Say Y if you want support for the ARM940T processor. 216 Otherwise, say N. 217 218# ARM946E-S 219config CPU_ARM946E 220 bool "Support ARM946E-S processor" if ARCH_INTEGRATOR 221 depends on !MMU 222 select CPU_32v5 223 select CPU_ABRT_NOMMU 224 select CPU_PABRT_LEGACY 225 select CPU_CACHE_VIVT 226 select CPU_CP15_MPU 227 help 228 ARM946E-S is a member of the ARM9E-S family of high- 229 performance, 32-bit system-on-chip processor solutions. 230 The TCM and ARMv5TE 32-bit instruction set is supported. 231 232 Say Y if you want support for the ARM946E-S processor. 233 Otherwise, say N. 234 235# ARM1020 - needs validating 236config CPU_ARM1020 237 bool "Support ARM1020T (rev 0) processor" if ARCH_INTEGRATOR 238 select CPU_32v5 239 select CPU_ABRT_EV4T 240 select CPU_PABRT_LEGACY 241 select CPU_CACHE_V4WT 242 select CPU_CACHE_VIVT 243 select CPU_CP15_MMU 244 select CPU_COPY_V4WB if MMU 245 select CPU_TLB_V4WBI if MMU 246 help 247 The ARM1020 is the 32K cached version of the ARM10 processor, 248 with an addition of a floating-point unit. 249 250 Say Y if you want support for the ARM1020 processor. 251 Otherwise, say N. 252 253# ARM1020E - needs validating 254config CPU_ARM1020E 255 bool "Support ARM1020E processor" if ARCH_INTEGRATOR 256 select CPU_32v5 257 select CPU_ABRT_EV4T 258 select CPU_PABRT_LEGACY 259 select CPU_CACHE_V4WT 260 select CPU_CACHE_VIVT 261 select CPU_CP15_MMU 262 select CPU_COPY_V4WB if MMU 263 select CPU_TLB_V4WBI if MMU 264 depends on n 265 266# ARM1022E 267config CPU_ARM1022 268 bool "Support ARM1022E processor" if ARCH_INTEGRATOR 269 select CPU_32v5 270 select CPU_ABRT_EV4T 271 select CPU_PABRT_LEGACY 272 select CPU_CACHE_VIVT 273 select CPU_CP15_MMU 274 select CPU_COPY_V4WB if MMU # can probably do better 275 select CPU_TLB_V4WBI if MMU 276 help 277 The ARM1022E is an implementation of the ARMv5TE architecture 278 based upon the ARM10 integer core with a 16KiB L1 Harvard cache, 279 embedded trace macrocell, and a floating-point unit. 280 281 Say Y if you want support for the ARM1022E processor. 282 Otherwise, say N. 283 284# ARM1026EJ-S 285config CPU_ARM1026 286 bool "Support ARM1026EJ-S processor" if ARCH_INTEGRATOR 287 select CPU_32v5 288 select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10 289 select CPU_PABRT_LEGACY 290 select CPU_CACHE_VIVT 291 select CPU_CP15_MMU 292 select CPU_COPY_V4WB if MMU # can probably do better 293 select CPU_TLB_V4WBI if MMU 294 help 295 The ARM1026EJ-S is an implementation of the ARMv5TEJ architecture 296 based upon the ARM10 integer core. 297 298 Say Y if you want support for the ARM1026EJ-S processor. 299 Otherwise, say N. 300 301# SA110 302config CPU_SA110 303 bool "Support StrongARM(R) SA-110 processor" if ARCH_RPC 304 select CPU_32v3 if ARCH_RPC 305 select CPU_32v4 if !ARCH_RPC 306 select CPU_ABRT_EV4 307 select CPU_PABRT_LEGACY 308 select CPU_CACHE_V4WB 309 select CPU_CACHE_VIVT 310 select CPU_CP15_MMU 311 select CPU_COPY_V4WB if MMU 312 select CPU_TLB_V4WB if MMU 313 help 314 The Intel StrongARM(R) SA-110 is a 32-bit microprocessor and 315 is available at five speeds ranging from 100 MHz to 233 MHz. 316 More information is available at 317 <http://developer.intel.com/design/strong/sa110.htm>. 318 319 Say Y if you want support for the SA-110 processor. 320 Otherwise, say N. 321 322# SA1100 323config CPU_SA1100 324 bool 325 select CPU_32v4 326 select CPU_ABRT_EV4 327 select CPU_PABRT_LEGACY 328 select CPU_CACHE_V4WB 329 select CPU_CACHE_VIVT 330 select CPU_CP15_MMU 331 select CPU_TLB_V4WB if MMU 332 333# XScale 334config CPU_XSCALE 335 bool 336 select CPU_32v5 337 select CPU_ABRT_EV5T 338 select CPU_PABRT_LEGACY 339 select CPU_CACHE_VIVT 340 select CPU_CP15_MMU 341 select CPU_TLB_V4WBI if MMU 342 343# XScale Core Version 3 344config CPU_XSC3 345 bool 346 select CPU_32v5 347 select CPU_ABRT_EV5T 348 select CPU_PABRT_LEGACY 349 select CPU_CACHE_VIVT 350 select CPU_CP15_MMU 351 select CPU_TLB_V4WBI if MMU 352 select IO_36 353 354# Marvell PJ1 (Mohawk) 355config CPU_MOHAWK 356 bool 357 select CPU_32v5 358 select CPU_ABRT_EV5T 359 select CPU_PABRT_LEGACY 360 select CPU_CACHE_VIVT 361 select CPU_CP15_MMU 362 select CPU_TLB_V4WBI if MMU 363 select CPU_COPY_V4WB if MMU 364 365# Feroceon 366config CPU_FEROCEON 367 bool 368 select CPU_32v5 369 select CPU_ABRT_EV5T 370 select CPU_PABRT_LEGACY 371 select CPU_CACHE_VIVT 372 select CPU_CP15_MMU 373 select CPU_COPY_FEROCEON if MMU 374 select CPU_TLB_FEROCEON if MMU 375 376config CPU_FEROCEON_OLD_ID 377 bool "Accept early Feroceon cores with an ARM926 ID" 378 depends on CPU_FEROCEON && !CPU_ARM926T 379 default y 380 help 381 This enables the usage of some old Feroceon cores 382 for which the CPU ID is equal to the ARM926 ID. 383 Relevant for Feroceon-1850 and early Feroceon-2850. 384 385# Marvell PJ4 386config CPU_PJ4 387 bool 388 select CPU_V7 389 select ARM_THUMBEE 390 391# ARMv6 392config CPU_V6 393 bool "Support ARM V6 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX 394 select CPU_32v6 395 select CPU_ABRT_EV6 396 select CPU_PABRT_V6 397 select CPU_CACHE_V6 398 select CPU_CACHE_VIPT 399 select CPU_CP15_MMU 400 select CPU_HAS_ASID if MMU 401 select CPU_COPY_V6 if MMU 402 select CPU_TLB_V6 if MMU 403 404# ARMv6k 405config CPU_V6K 406 bool "Support ARM V6K processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX 407 select CPU_32v6 408 select CPU_32v6K 409 select CPU_ABRT_EV6 410 select CPU_PABRT_V6 411 select CPU_CACHE_V6 412 select CPU_CACHE_VIPT 413 select CPU_CP15_MMU 414 select CPU_HAS_ASID if MMU 415 select CPU_COPY_V6 if MMU 416 select CPU_TLB_V6 if MMU 417 418# ARMv7 419config CPU_V7 420 bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX 421 select CPU_32v6K 422 select CPU_32v7 423 select CPU_ABRT_EV7 424 select CPU_PABRT_V7 425 select CPU_CACHE_V7 426 select CPU_CACHE_VIPT 427 select CPU_CP15_MMU 428 select CPU_HAS_ASID if MMU 429 select CPU_COPY_V6 if MMU 430 select CPU_TLB_V7 if MMU 431 432# Figure out what processor architecture version we should be using. 433# This defines the compiler instruction set which depends on the machine type. 434config CPU_32v3 435 bool 436 select TLS_REG_EMUL if SMP || !MMU 437 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP 438 select CPU_USE_DOMAINS if MMU 439 440config CPU_32v4 441 bool 442 select TLS_REG_EMUL if SMP || !MMU 443 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP 444 select CPU_USE_DOMAINS if MMU 445 446config CPU_32v4T 447 bool 448 select TLS_REG_EMUL if SMP || !MMU 449 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP 450 select CPU_USE_DOMAINS if MMU 451 452config CPU_32v5 453 bool 454 select TLS_REG_EMUL if SMP || !MMU 455 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP 456 select CPU_USE_DOMAINS if MMU 457 458config CPU_32v6 459 bool 460 select TLS_REG_EMUL if !CPU_32v6K && !MMU 461 select CPU_USE_DOMAINS if CPU_V6 && MMU 462 463config CPU_32v6K 464 bool 465 466config CPU_32v7 467 bool 468 469# The abort model 470config CPU_ABRT_NOMMU 471 bool 472 473config CPU_ABRT_EV4 474 bool 475 476config CPU_ABRT_EV4T 477 bool 478 479config CPU_ABRT_LV4T 480 bool 481 482config CPU_ABRT_EV5T 483 bool 484 485config CPU_ABRT_EV5TJ 486 bool 487 488config CPU_ABRT_EV6 489 bool 490 491config CPU_ABRT_EV7 492 bool 493 494config CPU_PABRT_LEGACY 495 bool 496 497config CPU_PABRT_V6 498 bool 499 500config CPU_PABRT_V7 501 bool 502 503# The cache model 504config CPU_CACHE_V3 505 bool 506 507config CPU_CACHE_V4 508 bool 509 510config CPU_CACHE_V4WT 511 bool 512 513config CPU_CACHE_V4WB 514 bool 515 516config CPU_CACHE_V6 517 bool 518 519config CPU_CACHE_V7 520 bool 521 522config CPU_CACHE_VIVT 523 bool 524 525config CPU_CACHE_VIPT 526 bool 527 528config CPU_CACHE_FA 529 bool 530 531if MMU 532# The copy-page model 533config CPU_COPY_V3 534 bool 535 536config CPU_COPY_V4WT 537 bool 538 539config CPU_COPY_V4WB 540 bool 541 542config CPU_COPY_FEROCEON 543 bool 544 545config CPU_COPY_FA 546 bool 547 548config CPU_COPY_V6 549 bool 550 551# This selects the TLB model 552config CPU_TLB_V3 553 bool 554 help 555 ARM Architecture Version 3 TLB. 556 557config CPU_TLB_V4WT 558 bool 559 help 560 ARM Architecture Version 4 TLB with writethrough cache. 561 562config CPU_TLB_V4WB 563 bool 564 help 565 ARM Architecture Version 4 TLB with writeback cache. 566 567config CPU_TLB_V4WBI 568 bool 569 help 570 ARM Architecture Version 4 TLB with writeback cache and invalidate 571 instruction cache entry. 572 573config CPU_TLB_FEROCEON 574 bool 575 help 576 Feroceon TLB (v4wbi with non-outer-cachable page table walks). 577 578config CPU_TLB_FA 579 bool 580 help 581 Faraday ARM FA526 architecture, unified TLB with writeback cache 582 and invalidate instruction cache entry. Branch target buffer is 583 also supported. 584 585config CPU_TLB_V6 586 bool 587 588config CPU_TLB_V7 589 bool 590 591config VERIFY_PERMISSION_FAULT 592 bool 593endif 594 595config CPU_HAS_ASID 596 bool 597 help 598 This indicates whether the CPU has the ASID register; used to 599 tag TLB and possibly cache entries. 600 601config CPU_CP15 602 bool 603 help 604 Processor has the CP15 register. 605 606config CPU_CP15_MMU 607 bool 608 select CPU_CP15 609 help 610 Processor has the CP15 register, which has MMU related registers. 611 612config CPU_CP15_MPU 613 bool 614 select CPU_CP15 615 help 616 Processor has the CP15 register, which has MPU related registers. 617 618config CPU_USE_DOMAINS 619 bool 620 help 621 This option enables or disables the use of domain switching 622 via the set_fs() function. 623 624# 625# CPU supports 36-bit I/O 626# 627config IO_36 628 bool 629 630comment "Processor Features" 631 632config ARM_LPAE 633 bool "Support for the Large Physical Address Extension" 634 depends on MMU && CPU_V7 635 help 636 Say Y if you have an ARMv7 processor supporting the LPAE page 637 table format and you would like to access memory beyond the 638 4GB limit. The resulting kernel image will not run on 639 processors without the LPA extension. 640 641 If unsure, say N. 642 643config ARCH_PHYS_ADDR_T_64BIT 644 def_bool ARM_LPAE 645 646config ARCH_DMA_ADDR_T_64BIT 647 bool 648 649config ARM_THUMB 650 bool "Support Thumb user binaries" 651 depends on CPU_ARM720T || CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_V6 || CPU_V6K || CPU_V7 || CPU_FEROCEON 652 default y 653 help 654 Say Y if you want to include kernel support for running user space 655 Thumb binaries. 656 657 The Thumb instruction set is a compressed form of the standard ARM 658 instruction set resulting in smaller binaries at the expense of 659 slightly less efficient code. 660 661 If you don't know what this all is, saying Y is a safe choice. 662 663config ARM_THUMBEE 664 bool "Enable ThumbEE CPU extension" 665 depends on CPU_V7 666 help 667 Say Y here if you have a CPU with the ThumbEE extension and code to 668 make use of it. Say N for code that can run on CPUs without ThumbEE. 669 670config SWP_EMULATE 671 bool "Emulate SWP/SWPB instructions" 672 depends on !CPU_USE_DOMAINS && CPU_V7 673 select HAVE_PROC_CPU if PROC_FS 674 default y if SMP 675 help 676 ARMv6 architecture deprecates use of the SWP/SWPB instructions. 677 ARMv7 multiprocessing extensions introduce the ability to disable 678 these instructions, triggering an undefined instruction exception 679 when executed. Say Y here to enable software emulation of these 680 instructions for userspace (not kernel) using LDREX/STREX. 681 Also creates /proc/cpu/swp_emulation for statistics. 682 683 In some older versions of glibc [<=2.8] SWP is used during futex 684 trylock() operations with the assumption that the code will not 685 be preempted. This invalid assumption may be more likely to fail 686 with SWP emulation enabled, leading to deadlock of the user 687 application. 688 689 NOTE: when accessing uncached shared regions, LDREX/STREX rely 690 on an external transaction monitoring block called a global 691 monitor to maintain update atomicity. If your system does not 692 implement a global monitor, this option can cause programs that 693 perform SWP operations to uncached memory to deadlock. 694 695 If unsure, say Y. 696 697config CPU_BIG_ENDIAN 698 bool "Build big-endian kernel" 699 depends on ARCH_SUPPORTS_BIG_ENDIAN 700 help 701 Say Y if you plan on running a kernel in big-endian mode. 702 Note that your board must be properly built and your board 703 port must properly enable any big-endian related features 704 of your chipset/board/processor. 705 706config CPU_ENDIAN_BE8 707 bool 708 depends on CPU_BIG_ENDIAN 709 default CPU_V6 || CPU_V6K || CPU_V7 710 help 711 Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors. 712 713config CPU_ENDIAN_BE32 714 bool 715 depends on CPU_BIG_ENDIAN 716 default !CPU_ENDIAN_BE8 717 help 718 Support for the BE-32 (big-endian) mode on pre-ARMv6 processors. 719 720config CPU_HIGH_VECTOR 721 depends on !MMU && CPU_CP15 && !CPU_ARM740T 722 bool "Select the High exception vector" 723 help 724 Say Y here to select high exception vector(0xFFFF0000~). 725 The exception vector can be vary depending on the platform 726 design in nommu mode. If your platform needs to select 727 high exception vector, say Y. 728 Otherwise or if you are unsure, say N, and the low exception 729 vector (0x00000000~) will be used. 730 731config CPU_ICACHE_DISABLE 732 bool "Disable I-Cache (I-bit)" 733 depends on CPU_CP15 && !(CPU_ARM610 || CPU_ARM710 || CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3) 734 help 735 Say Y here to disable the processor instruction cache. Unless 736 you have a reason not to or are unsure, say N. 737 738config CPU_DCACHE_DISABLE 739 bool "Disable D-Cache (C-bit)" 740 depends on CPU_CP15 741 help 742 Say Y here to disable the processor data cache. Unless 743 you have a reason not to or are unsure, say N. 744 745config CPU_DCACHE_SIZE 746 hex 747 depends on CPU_ARM740T || CPU_ARM946E 748 default 0x00001000 if CPU_ARM740T 749 default 0x00002000 # default size for ARM946E-S 750 help 751 Some cores are synthesizable to have various sized cache. For 752 ARM946E-S case, it can vary from 0KB to 1MB. 753 To support such cache operations, it is efficient to know the size 754 before compile time. 755 If your SoC is configured to have a different size, define the value 756 here with proper conditions. 757 758config CPU_DCACHE_WRITETHROUGH 759 bool "Force write through D-cache" 760 depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_FA526) && !CPU_DCACHE_DISABLE 761 default y if CPU_ARM925T 762 help 763 Say Y here to use the data cache in writethrough mode. Unless you 764 specifically require this or are unsure, say N. 765 766config CPU_CACHE_ROUND_ROBIN 767 bool "Round robin I and D cache replacement algorithm" 768 depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE) 769 help 770 Say Y here to use the predictable round-robin cache replacement 771 policy. Unless you specifically require this or are unsure, say N. 772 773config CPU_BPREDICT_DISABLE 774 bool "Disable branch prediction" 775 depends on CPU_ARM1020 || CPU_V6 || CPU_V6K || CPU_MOHAWK || CPU_XSC3 || CPU_V7 || CPU_FA526 776 help 777 Say Y here to disable branch prediction. If unsure, say N. 778 779config TLS_REG_EMUL 780 bool 781 help 782 An SMP system using a pre-ARMv6 processor (there are apparently 783 a few prototypes like that in existence) and therefore access to 784 that required register must be emulated. 785 786config NEEDS_SYSCALL_FOR_CMPXCHG 787 bool 788 help 789 SMP on a pre-ARMv6 processor? Well OK then. 790 Forget about fast user space cmpxchg support. 791 It is just not possible. 792 793config DMA_CACHE_RWFO 794 bool "Enable read/write for ownership DMA cache maintenance" 795 depends on CPU_V6K && SMP 796 default y 797 help 798 The Snoop Control Unit on ARM11MPCore does not detect the 799 cache maintenance operations and the dma_{map,unmap}_area() 800 functions may leave stale cache entries on other CPUs. By 801 enabling this option, Read or Write For Ownership in the ARMv6 802 DMA cache maintenance functions is performed. These LDR/STR 803 instructions change the cache line state to shared or modified 804 so that the cache operation has the desired effect. 805 806 Note that the workaround is only valid on processors that do 807 not perform speculative loads into the D-cache. For such 808 processors, if cache maintenance operations are not broadcast 809 in hardware, other workarounds are needed (e.g. cache 810 maintenance broadcasting in software via FIQ). 811 812config OUTER_CACHE 813 bool 814 815config OUTER_CACHE_SYNC 816 bool 817 help 818 The outer cache has a outer_cache_fns.sync function pointer 819 that can be used to drain the write buffer of the outer cache. 820 821config CACHE_FEROCEON_L2 822 bool "Enable the Feroceon L2 cache controller" 823 depends on ARCH_KIRKWOOD || ARCH_MV78XX0 824 default y 825 select OUTER_CACHE 826 help 827 This option enables the Feroceon L2 cache controller. 828 829config CACHE_FEROCEON_L2_WRITETHROUGH 830 bool "Force Feroceon L2 cache write through" 831 depends on CACHE_FEROCEON_L2 832 help 833 Say Y here to use the Feroceon L2 cache in writethrough mode. 834 Unless you specifically require this, say N for writeback mode. 835 836config MIGHT_HAVE_CACHE_L2X0 837 bool 838 help 839 This option should be selected by machines which have a L2x0 840 or PL310 cache controller, but where its use is optional. 841 842 The only effect of this option is to make CACHE_L2X0 and 843 related options available to the user for configuration. 844 845 Boards or SoCs which always require the cache controller 846 support to be present should select CACHE_L2X0 directly 847 instead of this option, thus preventing the user from 848 inadvertently configuring a broken kernel. 849 850config CACHE_L2X0 851 bool "Enable the L2x0 outer cache controller" if MIGHT_HAVE_CACHE_L2X0 852 default MIGHT_HAVE_CACHE_L2X0 853 select OUTER_CACHE 854 select OUTER_CACHE_SYNC 855 help 856 This option enables the L2x0 PrimeCell. 857 858config CACHE_PL310 859 bool 860 depends on CACHE_L2X0 861 default y if CPU_V7 && !(CPU_V6 || CPU_V6K) 862 help 863 This option enables optimisations for the PL310 cache 864 controller. 865 866config CACHE_TAUROS2 867 bool "Enable the Tauros2 L2 cache controller" 868 depends on (ARCH_DOVE || ARCH_MMP || CPU_PJ4) 869 default y 870 select OUTER_CACHE 871 help 872 This option enables the Tauros2 L2 cache controller (as 873 found on PJ1/PJ4). 874 875config CACHE_XSC3L2 876 bool "Enable the L2 cache on XScale3" 877 depends on CPU_XSC3 878 default y 879 select OUTER_CACHE 880 help 881 This option enables the L2 cache on XScale3. 882 883config ARM_L1_CACHE_SHIFT_6 884 bool 885 default y if CPU_V7 886 help 887 Setting ARM L1 cache line size to 64 Bytes. 888 889config ARM_L1_CACHE_SHIFT 890 int 891 default 6 if ARM_L1_CACHE_SHIFT_6 892 default 5 893 894config ARM_DMA_MEM_BUFFERABLE 895 bool "Use non-cacheable memory for DMA" if (CPU_V6 || CPU_V6K) && !CPU_V7 896 depends on !(MACH_REALVIEW_PB1176 || REALVIEW_EB_ARM11MP || \ 897 MACH_REALVIEW_PB11MP) 898 default y if CPU_V6 || CPU_V6K || CPU_V7 899 help 900 Historically, the kernel has used strongly ordered mappings to 901 provide DMA coherent memory. With the advent of ARMv7, mapping 902 memory with differing types results in unpredictable behaviour, 903 so on these CPUs, this option is forced on. 904 905 Multiple mappings with differing attributes is also unpredictable 906 on ARMv6 CPUs, but since they do not have aggressive speculative 907 prefetch, no harm appears to occur. 908 909 However, drivers may be missing the necessary barriers for ARMv6, 910 and therefore turning this on may result in unpredictable driver 911 behaviour. Therefore, we offer this as an option. 912 913 You are recommended say 'Y' here and debug any affected drivers. 914 915config ARCH_HAS_BARRIERS 916 bool 917 help 918 This option allows the use of custom mandatory barriers 919 included via the mach/barriers.h file. 920