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_DMA_PREP_COHERENT if MMU
7 select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
8 select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
9 select ARCH_HAS_DMA_SET_UNCACHED if MMU
10 select ARCH_USE_QUEUED_RWLOCKS
11 select ARCH_USE_QUEUED_SPINLOCKS
12 select ARCH_WANT_FRAME_POINTERS
13 select ARCH_WANT_IPC_PARSE_VERSION
14 select BUILDTIME_TABLE_SORT
15 select CLONE_BACKWARDS
17 select DMA_REMAP if MMU
18 select GENERIC_ATOMIC64
19 select GENERIC_CLOCKEVENTS
20 select GENERIC_IRQ_SHOW
21 select GENERIC_PCI_IOMAP
22 select GENERIC_SCHED_CLOCK
23 select GENERIC_STRNCPY_FROM_USER if KASAN
24 select HAVE_ARCH_AUDITSYSCALL
25 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
26 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
27 select HAVE_ARCH_SECCOMP_FILTER
28 select HAVE_ARCH_TRACEHOOK
29 select HAVE_COPY_THREAD_TLS
30 select HAVE_DEBUG_KMEMLEAK
31 select HAVE_DMA_CONTIGUOUS
32 select HAVE_EXIT_THREAD
33 select HAVE_FUNCTION_TRACER
34 select HAVE_FUTEX_CMPXCHG if !MMU
35 select HAVE_HW_BREAKPOINT if PERF_EVENTS
36 select HAVE_IRQ_TIME_ACCOUNTING
39 select HAVE_PERF_EVENTS
40 select HAVE_STACKPROTECTOR
41 select HAVE_SYSCALL_TRACEPOINTS
43 select MODULES_USE_ELF_RELA
44 select PERF_USE_VMALLOC
47 Xtensa processors are 32-bit RISC machines designed by Tensilica
48 primarily for embedded systems. These processors are both
49 configurable and extensible. The Linux port to the Xtensa
50 architecture supports all processor configurations and extensions,
51 with reasonable minimum requirements. The Xtensa Linux project has
52 a home page at <http://www.linux-xtensa.org/>.
54 config GENERIC_HWEIGHT
57 config ARCH_HAS_ILOG2_U32
60 config ARCH_HAS_ILOG2_U64
70 config LOCKDEP_SUPPORT
73 config STACKTRACE_SUPPORT
76 config TRACE_IRQFLAGS_SUPPORT
82 config HAVE_XTENSA_GPIO32
85 config KASAN_SHADOW_OFFSET
89 menu "Processor type and features"
92 prompt "Xtensa Processor Configuration"
93 default XTENSA_VARIANT_FSF
95 config XTENSA_VARIANT_FSF
96 bool "fsf - default (not generic) configuration"
99 config XTENSA_VARIANT_DC232B
100 bool "dc232b - Diamond 232L Standard Core Rev.B (LE)"
102 select HAVE_XTENSA_GPIO32
104 This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
106 config XTENSA_VARIANT_DC233C
107 bool "dc233c - Diamond 233L Standard Core Rev.C (LE)"
109 select HAVE_XTENSA_GPIO32
111 This variant refers to Tensilica's Diamond 233L Standard core Rev.C (LE).
113 config XTENSA_VARIANT_CUSTOM
114 bool "Custom Xtensa processor configuration"
115 select HAVE_XTENSA_GPIO32
117 Select this variant to use a custom Xtensa processor configuration.
118 You will be prompted for a processor variant CORENAME.
121 config XTENSA_VARIANT_CUSTOM_NAME
122 string "Xtensa Processor Custom Core Variant Name"
123 depends on XTENSA_VARIANT_CUSTOM
125 Provide the name of a custom Xtensa processor variant.
126 This CORENAME selects arch/xtensa/variant/CORENAME.
127 Don't forget you have to select MMU if you have one.
129 config XTENSA_VARIANT_NAME
131 default "dc232b" if XTENSA_VARIANT_DC232B
132 default "dc233c" if XTENSA_VARIANT_DC233C
133 default "fsf" if XTENSA_VARIANT_FSF
134 default XTENSA_VARIANT_CUSTOM_NAME if XTENSA_VARIANT_CUSTOM
136 config XTENSA_VARIANT_MMU
137 bool "Core variant has a Full MMU (TLB, Pages, Protection, etc)"
138 depends on XTENSA_VARIANT_CUSTOM
142 Build a Conventional Kernel with full MMU support,
143 ie: it supports a TLB with auto-loading, page protection.
145 config XTENSA_VARIANT_HAVE_PERF_EVENTS
146 bool "Core variant has Performance Monitor Module"
147 depends on XTENSA_VARIANT_CUSTOM
150 Enable if core variant has Performance Monitor Module with
151 External Registers Interface.
155 config XTENSA_FAKE_NMI
156 bool "Treat PMM IRQ as NMI"
157 depends on XTENSA_VARIANT_HAVE_PERF_EVENTS
160 If PMM IRQ is the only IRQ at EXCM level it is safe to
161 treat it as NMI, which improves accuracy of profiling.
163 If there are other interrupts at or above PMM IRQ priority level
164 but not above the EXCM level, PMM IRQ still may be treated as NMI,
165 but only if these IRQs are not used. There will be a build warning
166 saying that this is not safe, and a bugcheck if one of these IRQs
171 config XTENSA_UNALIGNED_USER
172 bool "Unaligned memory access in user space"
174 The Xtensa architecture currently does not handle unaligned
175 memory accesses in hardware but through an exception handler.
176 Per default, unaligned memory accesses are disabled in user space.
178 Say Y here to enable unaligned memory access in user space.
181 bool "System Supports SMP (MX)"
182 depends on XTENSA_VARIANT_CUSTOM
185 This option is used to indicate that the system-on-a-chip (SOC)
186 supports Multiprocessing. Multiprocessor support implemented above
187 the CPU core definition and currently needs to be selected manually.
189 Multiprocessor support is implemented with external cache and
190 interrupt controllers.
192 The MX interrupt distributer adds Interprocessor Interrupts
193 and causes the IRQ numbers to be increased by 4 for devices
194 like the open cores ethernet driver and the serial interface.
196 You still have to select "Enable SMP" to enable SMP on this SOC.
199 bool "Enable Symmetric multi-processing support"
201 select GENERIC_SMP_IDLE_THREAD
203 Enabled SMP Software; allows more than one CPU/CORE
204 to be activated during startup.
208 int "Maximum number of CPUs (2-32)"
213 bool "Enable CPU hotplug support"
216 Say Y here to allow turning CPUs off and on. CPUs can be
217 controlled through /sys/devices/system/cpu.
219 Say N if you want to disable CPU hotplug.
223 prompt "Enable seccomp to safely compute untrusted bytecode"
225 This kernel feature is useful for number crunching applications
226 that may need to compute untrusted bytecode during their
227 execution. By using pipes or other transports made available to
228 the process as file descriptors supporting the read/write
229 syscalls, it's possible to isolate those applications in
230 their own address space using seccomp. Once seccomp is
231 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
232 and the task is only allowed to execute a few safe syscalls
233 defined by each seccomp mode.
235 config FAST_SYSCALL_XTENSA
236 bool "Enable fast atomic syscalls"
239 fast_syscall_xtensa is a syscall that can make atomic operations
240 on UP kernel when processor has no s32c1i support.
242 This syscall is deprecated. It may have issues when called with
243 invalid arguments. It is provided only for backwards compatibility.
244 Only enable it if your userspace software requires it.
248 config FAST_SYSCALL_SPILL_REGISTERS
249 bool "Enable spill registers syscall"
252 fast_syscall_spill_registers is a syscall that spills all active
253 register windows of a calling userspace task onto its stack.
255 This syscall is deprecated. It may have issues when called with
256 invalid arguments. It is provided only for backwards compatibility.
257 Only enable it if your userspace software requires it.
261 config USER_ABI_CALL0
265 prompt "Userspace ABI"
266 default USER_ABI_DEFAULT
268 Select supported userspace ABI.
270 If unsure, choose the default ABI.
272 config USER_ABI_DEFAULT
273 bool "Default ABI only"
275 Assume default userspace ABI. For XEA2 cores it is windowed ABI.
276 call0 ABI binaries may be run on such kernel, but signal delivery
277 will not work correctly for them.
279 config USER_ABI_CALL0_ONLY
280 bool "Call0 ABI only"
281 select USER_ABI_CALL0
283 Select this option to support only call0 ABI in userspace.
284 Windowed ABI binaries will crash with a segfault caused by
285 an illegal instruction exception on the first 'entry' opcode.
287 Choose this option if you're planning to run only user code
288 built with call0 ABI.
290 config USER_ABI_CALL0_PROBE
291 bool "Support both windowed and call0 ABI by probing"
292 select USER_ABI_CALL0
294 Select this option to support both windowed and call0 userspace
295 ABIs. When enabled all processes are started with PS.WOE disabled
296 and a fast user exception handler for an illegal instruction is
297 used to turn on PS.WOE bit on the first 'entry' opcode executed by
300 This option should be enabled for the kernel that must support
301 both call0 and windowed ABIs in userspace at the same time.
303 Note that Xtensa ISA does not guarantee that entry opcode will
304 raise an illegal instruction exception on cores with XEA2 when
305 PS.WOE is disabled, check whether the target core supports it.
311 config XTENSA_CALIBRATE_CCOUNT
314 On some platforms (XT2000, for example), the CPU clock rate can
315 vary. The frequency can be determined, however, by measuring
316 against a well known, fixed frequency, such as an UART oscillator.
318 config SERIAL_CONSOLE
321 config PLATFORM_HAVE_XIP
324 menu "Platform options"
327 prompt "Xtensa System Type"
328 default XTENSA_PLATFORM_ISS
330 config XTENSA_PLATFORM_ISS
332 select XTENSA_CALIBRATE_CCOUNT
333 select SERIAL_CONSOLE
335 ISS is an acronym for Tensilica's Instruction Set Simulator.
337 config XTENSA_PLATFORM_XT2000
341 XT2000 is the name of Tensilica's feature-rich emulation platform.
342 This hardware is capable of running a full Linux distribution.
344 config XTENSA_PLATFORM_XTFPGA
346 select ETHOC if ETHERNET
347 select PLATFORM_WANT_DEFAULT_MEM if !MMU
348 select SERIAL_CONSOLE
349 select XTENSA_CALIBRATE_CCOUNT
350 select PLATFORM_HAVE_XIP
352 XTFPGA is the name of Tensilica board family (LX60, LX110, LX200, ML605).
353 This hardware is capable of running a full Linux distribution.
357 config PLATFORM_NR_IRQS
359 default 3 if XTENSA_PLATFORM_XT2000
362 config XTENSA_CPU_CLOCK
363 int "CPU clock rate [MHz]"
364 depends on !XTENSA_CALIBRATE_CCOUNT
367 config GENERIC_CALIBRATE_DELAY
368 bool "Auto calibration of the BogoMIPS value"
370 The BogoMIPS value can easily be derived from the CPU frequency.
373 bool "Default bootloader kernel arguments"
376 string "Initial kernel command string"
377 depends on CMDLINE_BOOL
378 default "console=ttyS0,38400 root=/dev/ram"
380 On some architectures (EBSA110 and CATS), there is currently no way
381 for the boot loader to pass arguments to the kernel. For these
382 architectures, you should supply some command-line options at build
383 time by entering them here. As a minimum, you should specify the
384 memory size and the root device (e.g., mem=64M root=/dev/nfs).
387 bool "Flattened Device Tree support"
389 select OF_EARLY_FLATTREE
391 Include support for flattened device tree machine descriptions.
393 config BUILTIN_DTB_SOURCE
394 string "DTB to build into the kernel image"
397 config PARSE_BOOTPARAM
398 bool "Parse bootparam block"
401 Parse parameters passed to the kernel from the bootloader. It may
402 be disabled if the kernel is known to run without the bootloader.
406 config BLK_DEV_SIMDISK
407 tristate "Host file-based simulated block device support"
409 depends on XTENSA_PLATFORM_ISS && BLOCK
411 Create block devices that map to files in the host file system.
412 Device binding to host file may be changed at runtime via proc
413 interface provided the device is not in use.
415 config BLK_DEV_SIMDISK_COUNT
416 int "Number of host file-based simulated block devices"
418 depends on BLK_DEV_SIMDISK
421 This is the default minimal number of created block devices.
422 Kernel/module parameter 'simdisk_count' may be used to change this
423 value at runtime. More file names (but no more than 10) may be
424 specified as parameters, simdisk_count grows accordingly.
426 config SIMDISK0_FILENAME
427 string "Host filename for the first simulated device"
428 depends on BLK_DEV_SIMDISK = y
431 Attach a first simdisk to a host file. Conventionally, this file
432 contains a root file system.
434 config SIMDISK1_FILENAME
435 string "Host filename for the second simulated device"
436 depends on BLK_DEV_SIMDISK = y && BLK_DEV_SIMDISK_COUNT != 1
439 Another simulated disk in a host file for a buildroot-independent
443 bool "Enable XTFPGA LCD driver"
444 depends on XTENSA_PLATFORM_XTFPGA
447 There's a 2x16 LCD on most of XTFPGA boards, kernel may output
448 progress messages there during bootup/shutdown. It may be useful
449 during board bringup.
453 config XTFPGA_LCD_BASE_ADDR
454 hex "XTFPGA LCD base address"
455 depends on XTFPGA_LCD
458 Base address of the LCD controller inside KIO region.
459 Different boards from XTFPGA family have LCD controller at different
460 addresses. Please consult prototyping user guide for your board for
461 the correct address. Wrong address here may lead to hardware lockup.
463 config XTFPGA_LCD_8BIT_ACCESS
464 bool "Use 8-bit access to XTFPGA LCD"
465 depends on XTFPGA_LCD
468 LCD may be connected with 4- or 8-bit interface, 8-bit access may
469 only be used with 8-bit interface. Please consult prototyping user
470 guide for your board for the correct interface width.
472 comment "Kernel memory layout"
474 config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
475 bool "Initialize Xtensa MMU inside the Linux kernel code"
476 depends on !XTENSA_VARIANT_FSF && !XTENSA_VARIANT_DC232B
477 default y if XTENSA_VARIANT_DC233C || XTENSA_VARIANT_CUSTOM
479 Earlier version initialized the MMU in the exception vector
480 before jumping to _startup in head.S and had an advantage that
481 it was possible to place a software breakpoint at 'reset' and
482 then enter your normal kernel breakpoints once the MMU was mapped
483 to the kernel mappings (0XC0000000).
485 This unfortunately won't work for U-Boot and likely also wont
486 work for using KEXEC to have a hot kernel ready for doing a
489 So now the MMU is initialized in head.S but it's necessary to
490 use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup.
491 xt-gdb can't place a Software Breakpoint in the 0XD region prior
492 to mapping the MMU and after mapping even if the area of low memory
493 was mapped gdb wouldn't remove the breakpoint on hitting it as the
494 PC wouldn't match. Since Hardware Breakpoints are recommended for
495 Linux configurations it seems reasonable to just assume they exist
496 and leave this older mechanism for unfortunate souls that choose
497 not to follow Tensilica's recommendation.
499 Selecting this will cause U-Boot to set the KERNEL Load and Entry
500 address at 0x00003000 instead of the mapped std of 0xD0003000.
505 bool "Kernel Execute-In-Place from ROM"
506 depends on PLATFORM_HAVE_XIP
508 Execute-In-Place allows the kernel to run from non-volatile storage
509 directly addressable by the CPU, such as NOR flash. This saves RAM
510 space since the text section of the kernel is not loaded from flash
511 to RAM. Read-write sections, such as the data section and stack,
512 are still copied to RAM. The XIP kernel is not compressed since
513 it has to run directly from flash, so it will take more space to
514 store it. The flash address used to link the kernel object files,
515 and for storing it, is configuration dependent. Therefore, if you
516 say Y here, you must know the proper physical address where to
517 store the kernel image depending on your own flash memory usage.
519 Also note that the make target becomes "make xipImage" rather than
520 "make Image" or "make uImage". The final kernel binary to put in
521 ROM memory will be arch/xtensa/boot/xipImage.
525 config MEMMAP_CACHEATTR
526 hex "Cache attributes for the memory address space"
530 These cache attributes are set up for noMMU systems. Each hex digit
531 specifies cache attributes for the corresponding 512MB memory
532 region: bits 0..3 -- for addresses 0x00000000..0x1fffffff,
533 bits 4..7 -- for addresses 0x20000000..0x3fffffff, and so on.
535 Cache attribute values are specific for the MMU type.
536 For region protection MMUs:
548 3: special (c and e are illegal, f is reserved).
552 2: WB, no-write-allocate cache,
557 hex "Physical address of the KSEG mapping"
558 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX && MMU
561 This is the physical address where KSEG is mapped. Please refer to
562 the chosen KSEG layout help for the required address alignment.
563 Unpacked kernel image (including vectors) must be located completely
565 Physical memory below this address is not available to linux.
567 If unsure, leave the default value here.
569 config KERNEL_VIRTUAL_ADDRESS
570 hex "Kernel virtual address"
571 depends on MMU && XIP_KERNEL
574 This is the virtual address where the XIP kernel is mapped.
575 XIP kernel may be mapped into KSEG or KIO region, virtual address
576 provided here must match kernel load address provided in
579 config KERNEL_LOAD_ADDRESS
580 hex "Kernel load address"
581 default 0x60003000 if !MMU
582 default 0x00003000 if MMU && INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
583 default 0xd0003000 if MMU && !INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
585 This is the address where the kernel is loaded.
586 It is virtual address for MMUv2 configurations and physical address
587 for all other configurations.
589 If unsure, leave the default value here.
592 prompt "Relocatable vectors location"
593 default XTENSA_VECTORS_IN_TEXT
595 Choose whether relocatable vectors are merged into the kernel .text
596 or placed separately at runtime. This option does not affect
597 configurations without VECBASE register where vectors are always
598 placed at their hardware-defined locations.
600 config XTENSA_VECTORS_IN_TEXT
601 bool "Merge relocatable vectors into kernel text"
604 This option puts relocatable vectors into the kernel .text section
605 with proper alignment.
606 This is a safe choice for most configurations.
608 config XTENSA_VECTORS_SEPARATE
609 bool "Put relocatable vectors at fixed address"
611 This option puts relocatable vectors at specific virtual address.
612 Vectors are merged with the .init data in the kernel image and
613 are copied into their designated location during kernel startup.
614 Use it to put vectors into IRAM or out of FLASH on kernels with
615 XIP-aware MTD support.
620 hex "Kernel vectors virtual address"
622 depends on XTENSA_VECTORS_SEPARATE
624 This is the virtual address of the (relocatable) vectors base.
625 It must be within KSEG if MMU is used.
628 hex "XIP kernel data virtual address"
629 depends on XIP_KERNEL
632 This is the virtual address where XIP kernel data is copied.
633 It must be within KSEG if MMU is used.
635 config PLATFORM_WANT_DEFAULT_MEM
638 config DEFAULT_MEM_START
640 prompt "PAGE_OFFSET/PHYS_OFFSET" if !MMU && PLATFORM_WANT_DEFAULT_MEM
641 default 0x60000000 if PLATFORM_WANT_DEFAULT_MEM
644 This is the base address used for both PAGE_OFFSET and PHYS_OFFSET
645 in noMMU configurations.
647 If unsure, leave the default value here.
652 default XTENSA_KSEG_MMU_V2
654 config XTENSA_KSEG_MMU_V2
655 bool "MMUv2: 128MB cached + 128MB uncached"
657 MMUv2 compatible kernel memory map: TLB way 5 maps 128MB starting
658 at KSEG_PADDR to 0xd0000000 with cache and to 0xd8000000
660 KSEG_PADDR must be aligned to 128MB.
662 config XTENSA_KSEG_256M
663 bool "256MB cached + 256MB uncached"
664 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
666 TLB way 6 maps 256MB starting at KSEG_PADDR to 0xb0000000
667 with cache and to 0xc0000000 without cache.
668 KSEG_PADDR must be aligned to 256MB.
670 config XTENSA_KSEG_512M
671 bool "512MB cached + 512MB uncached"
672 depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
674 TLB way 6 maps 512MB starting at KSEG_PADDR to 0xa0000000
675 with cache and to 0xc0000000 without cache.
676 KSEG_PADDR must be aligned to 256MB.
681 bool "High Memory Support"
684 Linux can use the full amount of RAM in the system by
685 default. However, the default MMUv2 setup only maps the
686 lowermost 128 MB of memory linearly to the areas starting
687 at 0xd0000000 (cached) and 0xd8000000 (uncached).
688 When there are more than 128 MB memory in the system not
689 all of it can be "permanently mapped" by the kernel.
690 The physical memory that's not permanently mapped is called
693 If you are compiling a kernel which will never run on a
694 machine with more than 128 MB total physical RAM, answer
699 config FORCE_MAX_ZONEORDER
700 int "Maximum zone order"
703 The kernel memory allocator divides physically contiguous memory
704 blocks into "zones", where each zone is a power of two number of
705 pages. This option selects the largest power of two that the kernel
706 keeps in the memory allocator. If you need to allocate very large
707 blocks of physically contiguous memory, then you may need to
710 This config option is actually maximum order plus one. For example,
711 a value of 11 means that the largest free memory block is 2^10 pages.
715 menu "Power management options"
717 source "kernel/power/Kconfig"