1 # SPDX-License-Identifier: GPL-2.0
4 select ARCH_32BIT_OFF_T
5 select ARCH_HAS_BINFMT_FLAT if !MMU
6 select ARCH_HAS_CURRENT_STACK_POINTER
7 select ARCH_HAS_DEBUG_VM_PGTABLE
8 select ARCH_HAS_DMA_PREP_COHERENT if MMU
9 select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
10 select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
11 select ARCH_HAS_DMA_SET_UNCACHED if MMU
12 select ARCH_HAS_STRNCPY_FROM_USER if !KASAN
13 select ARCH_HAS_STRNLEN_USER
14 select ARCH_USE_MEMTEST
15 select ARCH_USE_QUEUED_RWLOCKS
16 select ARCH_USE_QUEUED_SPINLOCKS
17 select ARCH_WANT_FRAME_POINTERS
18 select ARCH_WANT_IPC_PARSE_VERSION
19 select BUILDTIME_TABLE_SORT
20 select CLONE_BACKWARDS
22 select DMA_NONCOHERENT_MMAP if MMU
23 select GENERIC_ATOMIC64
24 select GENERIC_IRQ_SHOW
25 select GENERIC_LIB_CMPDI2
26 select GENERIC_LIB_MULDI3
27 select GENERIC_LIB_UCMPDI2
28 select GENERIC_PCI_IOMAP
29 select GENERIC_SCHED_CLOCK
30 select HAVE_ARCH_AUDITSYSCALL
31 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
32 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
33 select HAVE_ARCH_KCSAN
34 select HAVE_ARCH_SECCOMP_FILTER
35 select HAVE_ARCH_TRACEHOOK
36 select HAVE_CONTEXT_TRACKING
37 select HAVE_DEBUG_KMEMLEAK
38 select HAVE_DMA_CONTIGUOUS
39 select HAVE_EXIT_THREAD
40 select HAVE_FUNCTION_TRACER
41 select HAVE_GCC_PLUGINS if GCC_VERSION >= 120000
42 select HAVE_HW_BREAKPOINT if PERF_EVENTS
43 select HAVE_IRQ_TIME_ACCOUNTING
45 select HAVE_PERF_EVENTS
46 select HAVE_STACKPROTECTOR
47 select HAVE_SYSCALL_TRACEPOINTS
48 select HAVE_VIRT_CPU_ACCOUNTING_GEN
50 select MODULES_USE_ELF_RELA
51 select PERF_USE_VMALLOC
52 select TRACE_IRQFLAGS_SUPPORT
55 Xtensa processors are 32-bit RISC machines designed by Tensilica
56 primarily for embedded systems. These processors are both
57 configurable and extensible. The Linux port to the Xtensa
58 architecture supports all processor configurations and extensions,
59 with reasonable minimum requirements. The Xtensa Linux project has
60 a home page at <http://www.linux-xtensa.org/>.
62 config GENERIC_HWEIGHT
65 config ARCH_HAS_ILOG2_U32
68 config ARCH_HAS_ILOG2_U64
78 config LOCKDEP_SUPPORT
81 config STACKTRACE_SUPPORT
88 config HAVE_XTENSA_GPIO32
91 config KASAN_SHADOW_OFFSET
96 def_bool $(success,test "$(shell,echo __XTENSA_EB__ | $(CC) -E -P -)" = 1)
98 config CPU_LITTLE_ENDIAN
99 def_bool !CPU_BIG_ENDIAN
101 config CC_HAVE_CALL0_ABI
102 def_bool $(success,test "$(shell,echo __XTENSA_CALL0_ABI__ | $(CC) -mabi=call0 -E -P - 2>/dev/null)" = 1)
104 menu "Processor type and features"
107 prompt "Xtensa Processor Configuration"
108 default XTENSA_VARIANT_FSF
110 config XTENSA_VARIANT_FSF
111 bool "fsf - default (not generic) configuration"
114 config XTENSA_VARIANT_DC232B
115 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
117 select HAVE_XTENSA_GPIO32
119 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
121 config XTENSA_VARIANT_DC233C
122 bool "dc233c - Diamond 233L Standard Core Rev.C (LE)"
124 select HAVE_XTENSA_GPIO32
126 This variant refers to Tensilica's Diamond 233L Standard core Rev.C (LE).
128 config XTENSA_VARIANT_CUSTOM
129 bool "Custom Xtensa processor configuration"
130 select HAVE_XTENSA_GPIO32
132 Select this variant to use a custom Xtensa processor configuration.
133 You will be prompted for a processor variant CORENAME.
136 config XTENSA_VARIANT_CUSTOM_NAME
137 string "Xtensa Processor Custom Core Variant Name"
138 depends on XTENSA_VARIANT_CUSTOM
140 Provide the name of a custom Xtensa processor variant.
141 This CORENAME selects arch/xtensa/variant/CORENAME.
142 Don't forget you have to select MMU if you have one.
144 config XTENSA_VARIANT_NAME
146 default "dc232b" if XTENSA_VARIANT_DC232B
147 default "dc233c" if XTENSA_VARIANT_DC233C
148 default "fsf" if XTENSA_VARIANT_FSF
149 default XTENSA_VARIANT_CUSTOM_NAME if XTENSA_VARIANT_CUSTOM
151 config XTENSA_VARIANT_MMU
152 bool "Core variant has a Full MMU (TLB, Pages, Protection, etc)"
153 depends on XTENSA_VARIANT_CUSTOM
157 Build a Conventional Kernel with full MMU support,
158 ie: it supports a TLB with auto-loading, page protection.
160 config XTENSA_VARIANT_HAVE_PERF_EVENTS
161 bool "Core variant has Performance Monitor Module"
162 depends on XTENSA_VARIANT_CUSTOM
165 Enable if core variant has Performance Monitor Module with
166 External Registers Interface.
170 config XTENSA_FAKE_NMI
171 bool "Treat PMM IRQ as NMI"
172 depends on XTENSA_VARIANT_HAVE_PERF_EVENTS
175 If PMM IRQ is the only IRQ at EXCM level it is safe to
176 treat it as NMI, which improves accuracy of profiling.
178 If there are other interrupts at or above PMM IRQ priority level
179 but not above the EXCM level, PMM IRQ still may be treated as NMI,
180 but only if these IRQs are not used. There will be a build warning
181 saying that this is not safe, and a bugcheck if one of these IRQs
187 bool "Handle protection faults" if EXPERT && !MMU
190 Handle protection faults. MMU configurations must enable it.
191 noMMU configurations may disable it if used memory map never
192 generates protection faults or faults are always fatal.
196 config XTENSA_UNALIGNED_USER
197 bool "Unaligned memory access in user space"
199 The Xtensa architecture currently does not handle unaligned
200 memory accesses in hardware but through an exception handler.
201 Per default, unaligned memory accesses are disabled in user space.
203 Say Y here to enable unaligned memory access in user space.
206 bool "System Supports SMP (MX)"
207 depends on XTENSA_VARIANT_CUSTOM
210 This option is used to indicate that the system-on-a-chip (SOC)
211 supports Multiprocessing. Multiprocessor support implemented above
212 the CPU core definition and currently needs to be selected manually.
214 Multiprocessor support is implemented with external cache and
215 interrupt controllers.
217 The MX interrupt distributer adds Interprocessor Interrupts
218 and causes the IRQ numbers to be increased by 4 for devices
219 like the open cores ethernet driver and the serial interface.
221 You still have to select "Enable SMP" to enable SMP on this SOC.
224 bool "Enable Symmetric multi-processing support"
226 select GENERIC_SMP_IDLE_THREAD
228 Enabled SMP Software; allows more than one CPU/CORE
229 to be activated during startup.
233 int "Maximum number of CPUs (2-32)"
238 bool "Enable CPU hotplug support"
241 Say Y here to allow turning CPUs off and on. CPUs can be
242 controlled through /sys/devices/system/cpu.
244 Say N if you want to disable CPU hotplug.
246 config SECONDARY_RESET_VECTOR
247 bool "Secondary cores use alternative reset vector"
251 Secondary cores may be configured to use alternative reset vector,
252 or all cores may use primary reset vector.
253 Say Y here to supply handler for the alternative reset location.
255 config FAST_SYSCALL_XTENSA
256 bool "Enable fast atomic syscalls"
259 fast_syscall_xtensa is a syscall that can make atomic operations
260 on UP kernel when processor has no s32c1i support.
262 This syscall is deprecated. It may have issues when called with
263 invalid arguments. It is provided only for backwards compatibility.
264 Only enable it if your userspace software requires it.
268 config FAST_SYSCALL_SPILL_REGISTERS
269 bool "Enable spill registers syscall"
272 fast_syscall_spill_registers is a syscall that spills all active
273 register windows of a calling userspace task onto its stack.
275 This syscall is deprecated. It may have issues when called with
276 invalid arguments. It is provided only for backwards compatibility.
277 Only enable it if your userspace software requires it.
283 default KERNEL_ABI_DEFAULT
285 Select ABI for the kernel code. This ABI is independent of the
286 supported userspace ABI and any combination of the
287 kernel/userspace ABI is possible and should work.
289 In case both kernel and userspace support only call0 ABI
290 all register windows support code will be omitted from the
293 If unsure, choose the default ABI.
295 config KERNEL_ABI_DEFAULT
298 Select this option to compile kernel code with the default ABI
299 selected for the toolchain.
300 Normally cores with windowed registers option use windowed ABI and
301 cores without it use call0 ABI.
303 config KERNEL_ABI_CALL0
304 bool "Call0 ABI" if CC_HAVE_CALL0_ABI
306 Select this option to compile kernel code with call0 ABI even with
307 toolchain that defaults to windowed ABI.
308 When this option is not selected the default toolchain ABI will
309 be used for the kernel code.
313 config USER_ABI_CALL0
317 prompt "Userspace ABI"
318 default USER_ABI_DEFAULT
320 Select supported userspace ABI.
322 If unsure, choose the default ABI.
324 config USER_ABI_DEFAULT
325 bool "Default ABI only"
327 Assume default userspace ABI. For XEA2 cores it is windowed ABI.
328 call0 ABI binaries may be run on such kernel, but signal delivery
329 will not work correctly for them.
331 config USER_ABI_CALL0_ONLY
332 bool "Call0 ABI only"
333 select USER_ABI_CALL0
335 Select this option to support only call0 ABI in userspace.
336 Windowed ABI binaries will crash with a segfault caused by
337 an illegal instruction exception on the first 'entry' opcode.
339 Choose this option if you're planning to run only user code
340 built with call0 ABI.
342 config USER_ABI_CALL0_PROBE
343 bool "Support both windowed and call0 ABI by probing"
344 select USER_ABI_CALL0
346 Select this option to support both windowed and call0 userspace
347 ABIs. When enabled all processes are started with PS.WOE disabled
348 and a fast user exception handler for an illegal instruction is
349 used to turn on PS.WOE bit on the first 'entry' opcode executed by
352 This option should be enabled for the kernel that must support
353 both call0 and windowed ABIs in userspace at the same time.
355 Note that Xtensa ISA does not guarantee that entry opcode will
356 raise an illegal instruction exception on cores with XEA2 when
357 PS.WOE is disabled, check whether the target core supports it.
363 config XTENSA_CALIBRATE_CCOUNT
366 On some platforms (XT2000, for example), the CPU clock rate can
367 vary. The frequency can be determined, however, by measuring
368 against a well known, fixed frequency, such as an UART oscillator.
370 config SERIAL_CONSOLE
373 config PLATFORM_HAVE_XIP
376 menu "Platform options"
379 prompt "Xtensa System Type"
380 default XTENSA_PLATFORM_ISS
382 config XTENSA_PLATFORM_ISS
384 select XTENSA_CALIBRATE_CCOUNT
385 select SERIAL_CONSOLE
387 ISS is an acronym for Tensilica's Instruction Set Simulator.
389 config XTENSA_PLATFORM_XT2000
392 XT2000 is the name of Tensilica's feature-rich emulation platform.
393 This hardware is capable of running a full Linux distribution.
395 config XTENSA_PLATFORM_XTFPGA
397 select ETHOC if ETHERNET
398 select PLATFORM_WANT_DEFAULT_MEM if !MMU
399 select SERIAL_CONSOLE
400 select XTENSA_CALIBRATE_CCOUNT
401 select PLATFORM_HAVE_XIP
403 XTFPGA is the name of Tensilica board family (LX60, LX110, LX200, ML605).
404 This hardware is capable of running a full Linux distribution.
408 config PLATFORM_NR_IRQS
410 default 3 if XTENSA_PLATFORM_XT2000
413 config XTENSA_CPU_CLOCK
414 int "CPU clock rate [MHz]"
415 depends on !XTENSA_CALIBRATE_CCOUNT
418 config GENERIC_CALIBRATE_DELAY
419 bool "Auto calibration of the BogoMIPS value"
421 The BogoMIPS value can easily be derived from the CPU frequency.
424 bool "Default bootloader kernel arguments"
427 string "Initial kernel command string"
428 depends on CMDLINE_BOOL
429 default "console=ttyS0,38400 root=/dev/ram"
431 On some architectures (EBSA110 and CATS), there is currently no way
432 for the boot loader to pass arguments to the kernel. For these
433 architectures, you should supply some command-line options at build
434 time by entering them here. As a minimum, you should specify the
435 memory size and the root device (e.g., mem=64M root=/dev/nfs).
438 bool "Flattened Device Tree support"
440 select OF_EARLY_FLATTREE
442 Include support for flattened device tree machine descriptions.
444 config BUILTIN_DTB_SOURCE
445 string "DTB to build into the kernel image"
448 config PARSE_BOOTPARAM
449 bool "Parse bootparam block"
452 Parse parameters passed to the kernel from the bootloader. It may
453 be disabled if the kernel is known to run without the bootloader.
458 prompt "Semihosting interface"
459 default XTENSA_SIMCALL_ISS
460 depends on XTENSA_PLATFORM_ISS
462 Choose semihosting interface that will be used for serial port,
463 block device and networking.
465 config XTENSA_SIMCALL_ISS
468 Use simcall instruction. simcall is only available on simulators,
469 it does nothing on hardware.
471 config XTENSA_SIMCALL_GDBIO
474 Use break instruction. It is available on real hardware when GDB
475 is attached to it via JTAG.
479 config BLK_DEV_SIMDISK
480 tristate "Host file-based simulated block device support"
482 depends on XTENSA_PLATFORM_ISS && BLOCK
484 Create block devices that map to files in the host file system.
485 Device binding to host file may be changed at runtime via proc
486 interface provided the device is not in use.
488 config BLK_DEV_SIMDISK_COUNT
489 int "Number of host file-based simulated block devices"
491 depends on BLK_DEV_SIMDISK
494 This is the default minimal number of created block devices.
495 Kernel/module parameter 'simdisk_count' may be used to change this
496 value at runtime. More file names (but no more than 10) may be
497 specified as parameters, simdisk_count grows accordingly.
499 config SIMDISK0_FILENAME
500 string "Host filename for the first simulated device"
501 depends on BLK_DEV_SIMDISK = y
504 Attach a first simdisk to a host file. Conventionally, this file
505 contains a root file system.
507 config SIMDISK1_FILENAME
508 string "Host filename for the second simulated device"
509 depends on BLK_DEV_SIMDISK = y && BLK_DEV_SIMDISK_COUNT != 1
512 Another simulated disk in a host file for a buildroot-independent
516 bool "Enable XTFPGA LCD driver"
517 depends on XTENSA_PLATFORM_XTFPGA
520 There's a 2x16 LCD on most of XTFPGA boards, kernel may output
521 progress messages there during bootup/shutdown. It may be useful
522 during board bringup.
526 config XTFPGA_LCD_BASE_ADDR
527 hex "XTFPGA LCD base address"
528 depends on XTFPGA_LCD
531 Base address of the LCD controller inside KIO region.
532 Different boards from XTFPGA family have LCD controller at different
533 addresses. Please consult prototyping user guide for your board for
534 the correct address. Wrong address here may lead to hardware lockup.
536 config XTFPGA_LCD_8BIT_ACCESS
537 bool "Use 8-bit access to XTFPGA LCD"
538 depends on XTFPGA_LCD
541 LCD may be connected with 4- or 8-bit interface, 8-bit access may
542 only be used with 8-bit interface. Please consult prototyping user
543 guide for your board for the correct interface width.
545 comment "Kernel memory layout"
547 config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
548 bool "Initialize Xtensa MMU inside the Linux kernel code"
549 depends on !XTENSA_VARIANT_FSF && !XTENSA_VARIANT_DC232B
550 default y if XTENSA_VARIANT_DC233C || XTENSA_VARIANT_CUSTOM
552 Earlier version initialized the MMU in the exception vector
553 before jumping to _startup in head.S and had an advantage that
554 it was possible to place a software breakpoint at 'reset' and
555 then enter your normal kernel breakpoints once the MMU was mapped
556 to the kernel mappings (0XC0000000).
558 This unfortunately won't work for U-Boot and likely also won't
559 work for using KEXEC to have a hot kernel ready for doing a
562 So now the MMU is initialized in head.S but it's necessary to
563 use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
564 xt-gdb can't place a Software Breakpoint in the 0XD region prior
565 to mapping the MMU and after mapping even if the area of low memory
566 was mapped gdb wouldn't remove the breakpoint on hitting it as the
567 PC wouldn't match. Since Hardware Breakpoints are recommended for
568 Linux configurations it seems reasonable to just assume they exist
569 and leave this older mechanism for unfortunate souls that choose
570 not to follow Tensilica's recommendation.
572 Selecting this will cause U-Boot to set the KERNEL Load and Entry
573 address at 0x00003000 instead of the mapped std of 0xD0003000.
578 bool "Kernel Execute-In-Place from ROM"
579 depends on PLATFORM_HAVE_XIP
581 Execute-In-Place allows the kernel to run from non-volatile storage
582 directly addressable by the CPU, such as NOR flash. This saves RAM
583 space since the text section of the kernel is not loaded from flash
584 to RAM. Read-write sections, such as the data section and stack,
585 are still copied to RAM. The XIP kernel is not compressed since
586 it has to run directly from flash, so it will take more space to
587 store it. The flash address used to link the kernel object files,
588 and for storing it, is configuration dependent. Therefore, if you
589 say Y here, you must know the proper physical address where to
590 store the kernel image depending on your own flash memory usage.
592 Also note that the make target becomes "make xipImage" rather than
593 "make Image" or "make uImage". The final kernel binary to put in
594 ROM memory will be arch/xtensa/boot/xipImage.
598 config MEMMAP_CACHEATTR
599 hex "Cache attributes for the memory address space"
603 These cache attributes are set up for noMMU systems. Each hex digit
604 specifies cache attributes for the corresponding 512MB memory
605 region: bits 0..3 -- for addresses 0x00000000..0x1fffffff,
606 bits 4..7 -- for addresses 0x20000000..0x3fffffff, and so on.
608 Cache attribute values are specific for the MMU type.
609 For region protection MMUs:
621 3: special (c and e are illegal, f is reserved).
625 2: WB, no-write-allocate cache,
630 hex "Physical address of the KSEG mapping"
631 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX && MMU
634 This is the physical address where KSEG is mapped. Please refer to
635 the chosen KSEG layout help for the required address alignment.
636 Unpacked kernel image (including vectors) must be located completely
638 Physical memory below this address is not available to linux.
640 If unsure, leave the default value here.
642 config KERNEL_VIRTUAL_ADDRESS
643 hex "Kernel virtual address"
644 depends on MMU && XIP_KERNEL
647 This is the virtual address where the XIP kernel is mapped.
648 XIP kernel may be mapped into KSEG or KIO region, virtual address
649 provided here must match kernel load address provided in
652 config KERNEL_LOAD_ADDRESS
653 hex "Kernel load address"
654 default 0x60003000 if !MMU
655 default 0x00003000 if MMU && INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
656 default 0xd0003000 if MMU && !INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
658 This is the address where the kernel is loaded.
659 It is virtual address for MMUv2 configurations and physical address
660 for all other configurations.
662 If unsure, leave the default value here.
665 prompt "Relocatable vectors location"
666 default XTENSA_VECTORS_IN_TEXT
668 Choose whether relocatable vectors are merged into the kernel .text
669 or placed separately at runtime. This option does not affect
670 configurations without VECBASE register where vectors are always
671 placed at their hardware-defined locations.
673 config XTENSA_VECTORS_IN_TEXT
674 bool "Merge relocatable vectors into kernel text"
677 This option puts relocatable vectors into the kernel .text section
678 with proper alignment.
679 This is a safe choice for most configurations.
681 config XTENSA_VECTORS_SEPARATE
682 bool "Put relocatable vectors at fixed address"
684 This option puts relocatable vectors at specific virtual address.
685 Vectors are merged with the .init data in the kernel image and
686 are copied into their designated location during kernel startup.
687 Use it to put vectors into IRAM or out of FLASH on kernels with
688 XIP-aware MTD support.
693 hex "Kernel vectors virtual address"
695 depends on XTENSA_VECTORS_SEPARATE
697 This is the virtual address of the (relocatable) vectors base.
698 It must be within KSEG if MMU is used.
701 hex "XIP kernel data virtual address"
702 depends on XIP_KERNEL
705 This is the virtual address where XIP kernel data is copied.
706 It must be within KSEG if MMU is used.
708 config PLATFORM_WANT_DEFAULT_MEM
711 config DEFAULT_MEM_START
713 prompt "PAGE_OFFSET/PHYS_OFFSET" if !MMU && PLATFORM_WANT_DEFAULT_MEM
714 default 0x60000000 if PLATFORM_WANT_DEFAULT_MEM
717 This is the base address used for both PAGE_OFFSET and PHYS_OFFSET
718 in noMMU configurations.
720 If unsure, leave the default value here.
725 default XTENSA_KSEG_MMU_V2
727 config XTENSA_KSEG_MMU_V2
728 bool "MMUv2: 128MB cached + 128MB uncached"
730 MMUv2 compatible kernel memory map: TLB way 5 maps 128MB starting
731 at KSEG_PADDR to 0xd0000000 with cache and to 0xd8000000
733 KSEG_PADDR must be aligned to 128MB.
735 config XTENSA_KSEG_256M
736 bool "256MB cached + 256MB uncached"
737 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
739 TLB way 6 maps 256MB starting at KSEG_PADDR to 0xb0000000
740 with cache and to 0xc0000000 without cache.
741 KSEG_PADDR must be aligned to 256MB.
743 config XTENSA_KSEG_512M
744 bool "512MB cached + 512MB uncached"
745 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
747 TLB way 6 maps 512MB starting at KSEG_PADDR to 0xa0000000
748 with cache and to 0xc0000000 without cache.
749 KSEG_PADDR must be aligned to 256MB.
754 bool "High Memory Support"
758 Linux can use the full amount of RAM in the system by
759 default. However, the default MMUv2 setup only maps the
760 lowermost 128 MB of memory linearly to the areas starting
761 at 0xd0000000 (cached) and 0xd8000000 (uncached).
762 When there are more than 128 MB memory in the system not
763 all of it can be "permanently mapped" by the kernel.
764 The physical memory that's not permanently mapped is called
767 If you are compiling a kernel which will never run on a
768 machine with more than 128 MB total physical RAM, answer
773 config FORCE_MAX_ZONEORDER
774 int "Maximum zone order"
777 The kernel memory allocator divides physically contiguous memory
778 blocks into "zones", where each zone is a power of two number of
779 pages. This option selects the largest power of two that the kernel
780 keeps in the memory allocator. If you need to allocate very large
781 blocks of physically contiguous memory, then you may need to
784 This config option is actually maximum order plus one. For example,
785 a value of 11 means that the largest free memory block is 2^10 pages.
789 menu "Power management options"
791 config ARCH_HIBERNATION_POSSIBLE
794 source "kernel/power/Kconfig"