# SPDX-License-Identifier: GPL-2.0-only # # For a description of the syntax of this configuration file, # see Documentation/kbuild/kconfig-language.rst. # config 64BIT bool config 32BIT bool config RISCV def_bool y select ARCH_CLOCKSOURCE_INIT select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 select ARCH_HAS_BINFMT_FLAT select ARCH_HAS_CURRENT_STACK_POINTER select ARCH_HAS_DEBUG_VM_PGTABLE select ARCH_HAS_DEBUG_VIRTUAL if MMU select ARCH_HAS_DEBUG_WX select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_GIGANTIC_PAGE select ARCH_HAS_KCOV select ARCH_HAS_MMIOWB select ARCH_HAS_PTE_SPECIAL select ARCH_HAS_SET_DIRECT_MAP if MMU select ARCH_HAS_SET_MEMORY if MMU select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UBSAN_SANITIZE_ALL select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT select ARCH_STACKWALK select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU select ARCH_SUPPORTS_HUGETLBFS if MMU select ARCH_SUPPORTS_PAGE_TABLE_CHECK select ARCH_USE_MEMTEST select ARCH_USE_QUEUED_RWLOCKS select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE if 64BIT select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU select BUILDTIME_TABLE_SORT if MMU select CLONE_BACKWARDS select CLINT_TIMER if !MMU select COMMON_CLK select CPU_PM if CPU_IDLE select EDAC_SUPPORT select GENERIC_ARCH_TOPOLOGY if SMP select GENERIC_ATOMIC64 if !64BIT select GENERIC_CLOCKEVENTS_BROADCAST if SMP select GENERIC_EARLY_IOREMAP select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO select GENERIC_IDLE_POLL_SETUP select GENERIC_IOREMAP if MMU select GENERIC_IRQ_MULTI_HANDLER select GENERIC_IRQ_SHOW select GENERIC_IRQ_SHOW_LEVEL select GENERIC_LIB_DEVMEM_IS_ALLOWED select GENERIC_PCI_IOMAP select GENERIC_PTDUMP if MMU select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL if MMU && 64BIT select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL select HAVE_ARCH_KASAN if MMU && 64BIT select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT select HAVE_ARCH_KFENCE if MMU && 64BIT select HAVE_ARCH_KGDB if !XIP_KERNEL select HAVE_ARCH_KGDB_QXFER_PKT select HAVE_ARCH_MMAP_RND_BITS if MMU select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE select HAVE_ARCH_THREAD_STRUCT_WHITELIST select HAVE_ARCH_VMAP_STACK if MMU && 64BIT select HAVE_ASM_MODVERSIONS select HAVE_CONTEXT_TRACKING select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS if MMU select HAVE_EBPF_JIT if MMU select HAVE_FUNCTION_ERROR_INJECTION select HAVE_GCC_PLUGINS select HAVE_GENERIC_VDSO if MMU && 64BIT select HAVE_IRQ_TIME_ACCOUNTING select HAVE_KPROBES if !XIP_KERNEL select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL select HAVE_KRETPROBES if !XIP_KERNEL select HAVE_MOVE_PMD select HAVE_MOVE_PUD select HAVE_PCI select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_STACKPROTECTOR select HAVE_SYSCALL_TRACEPOINTS select HAVE_RSEQ select IRQ_DOMAIN select IRQ_FORCED_THREADING select MODULES_USE_ELF_RELA if MODULES select MODULE_SECTIONS if MODULES select OF select OF_EARLY_FLATTREE select OF_IRQ select PCI_DOMAINS_GENERIC if PCI select PCI_MSI if PCI select RISCV_INTC select RISCV_TIMER if RISCV_SBI select SPARSE_IRQ select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK select TRACE_IRQFLAGS_SUPPORT select UACCESS_MEMCPY if !MMU select ZONE_DMA32 if 64BIT config ARCH_MMAP_RND_BITS_MIN default 18 if 64BIT default 8 config ARCH_MMAP_RND_COMPAT_BITS_MIN default 8 # max bits determined by the following formula: # VA_BITS - PAGE_SHIFT - 3 config ARCH_MMAP_RND_BITS_MAX default 24 if 64BIT # SV39 based default 17 config ARCH_MMAP_RND_COMPAT_BITS_MAX default 17 # set if we run in machine mode, cleared if we run in supervisor mode config RISCV_M_MODE bool default !MMU # set if we are running in S-mode and can use SBI calls config RISCV_SBI bool depends on !RISCV_M_MODE default y config MMU bool "MMU-based Paged Memory Management Support" default y help Select if you want MMU-based virtualised addressing space support by paged memory management. If unsure, say 'Y'. config PAGE_OFFSET hex default 0xC0000000 if 32BIT default 0x80000000 if 64BIT && !MMU default 0xff60000000000000 if 64BIT config KASAN_SHADOW_OFFSET hex depends on KASAN_GENERIC default 0xdfffffff00000000 if 64BIT default 0xffffffff if 32BIT config ARCH_FLATMEM_ENABLE def_bool !NUMA config ARCH_SPARSEMEM_ENABLE def_bool y depends on MMU select SPARSEMEM_STATIC if 32BIT && SPARSEMEM select SPARSEMEM_VMEMMAP_ENABLE if 64BIT config ARCH_SELECT_MEMORY_MODEL def_bool ARCH_SPARSEMEM_ENABLE config ARCH_SUPPORTS_UPROBES def_bool y config STACKTRACE_SUPPORT def_bool y config GENERIC_BUG def_bool y depends on BUG select GENERIC_BUG_RELATIVE_POINTERS if 64BIT config GENERIC_BUG_RELATIVE_POINTERS bool config GENERIC_CALIBRATE_DELAY def_bool y config GENERIC_CSUM def_bool y config GENERIC_HWEIGHT def_bool y config FIX_EARLYCON_MEM def_bool MMU config PGTABLE_LEVELS int default 5 if 64BIT default 2 config LOCKDEP_SUPPORT def_bool y source "arch/riscv/Kconfig.socs" source "arch/riscv/Kconfig.erratas" menu "Platform type" choice prompt "Base ISA" default ARCH_RV64I help This selects the base ISA that this kernel will target and must match the target platform. config ARCH_RV32I bool "RV32I" select 32BIT select GENERIC_LIB_ASHLDI3 select GENERIC_LIB_ASHRDI3 select GENERIC_LIB_LSHRDI3 select GENERIC_LIB_UCMPDI2 select MMU config ARCH_RV64I bool "RV64I" select 64BIT select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8) select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER if !XIP_KERNEL select SWIOTLB if MMU endchoice # We must be able to map all physical memory into the kernel, but the compiler # is still a bit more efficient when generating code if it's setup in a manner # such that it can only map 2GiB of memory. choice prompt "Kernel Code Model" default CMODEL_MEDLOW if 32BIT default CMODEL_MEDANY if 64BIT config CMODEL_MEDLOW bool "medium low code model" config CMODEL_MEDANY bool "medium any code model" endchoice config MODULE_SECTIONS bool select HAVE_MOD_ARCH_SPECIFIC config SMP bool "Symmetric Multi-Processing" help This enables support for systems with more than one CPU. If you say N here, the kernel will run on single and multiprocessor machines, but will use only one CPU of a multiprocessor machine. If you say Y here, the kernel will run on many, but not all, single processor machines. On a single processor machine, the kernel will run faster if you say N here. If you don't know what to do here, say N. config NR_CPUS int "Maximum number of CPUs (2-32)" range 2 32 depends on SMP default "8" config HOTPLUG_CPU bool "Support for hot-pluggable CPUs" depends on SMP select GENERIC_IRQ_MIGRATION help Say Y here to experiment with turning CPUs off and on. CPUs can be controlled through /sys/devices/system/cpu. Say N if you want to disable CPU hotplug. choice prompt "CPU Tuning" default TUNE_GENERIC config TUNE_GENERIC bool "generic" endchoice # Common NUMA Features config NUMA bool "NUMA Memory Allocation and Scheduler Support" depends on SMP && MMU select GENERIC_ARCH_NUMA select OF_NUMA select ARCH_SUPPORTS_NUMA_BALANCING select USE_PERCPU_NUMA_NODE_ID select NEED_PER_CPU_EMBED_FIRST_CHUNK help Enable NUMA (Non-Uniform Memory Access) support. The kernel will try to allocate memory used by a CPU on the local memory of the CPU and add some more NUMA awareness to the kernel. config NODES_SHIFT int "Maximum NUMA Nodes (as a power of 2)" range 1 10 default "2" depends on NUMA help Specify the maximum number of NUMA Nodes available on the target system. Increases memory reserved to accommodate various tables. config RISCV_ALTERNATIVE bool depends on !XIP_KERNEL help This Kconfig allows the kernel to automatically patch the errata required by the execution platform at run time. The code patching is performed once in the boot stages. It means that the overhead from this mechanism is just taken once. config RISCV_ALTERNATIVE_EARLY bool depends on RISCV_ALTERNATIVE help Allows early patching of the kernel for special errata config RISCV_ISA_C bool "Emit compressed instructions when building Linux" default y help Adds "C" to the ISA subsets that the toolchain is allowed to emit when building Linux, which results in compressed instructions in the Linux binary. If you don't know what to do here, say Y. config RISCV_ISA_SVPBMT bool "SVPBMT extension support" depends on 64BIT && MMU select RISCV_ALTERNATIVE default y help Adds support to dynamically detect the presence of the SVPBMT extension (Supervisor-mode: page-based memory types) and enable its usage. The SVPBMT extension is only available on 64Bit cpus. If you don't know what to do here, say Y. config FPU bool "FPU support" default y help Say N here if you want to disable all floating-point related procedure in the kernel. If you don't know what to do here, say Y. endmenu menu "Kernel features" source "kernel/Kconfig.hz" config RISCV_SBI_V01 bool "SBI v0.1 support" depends on RISCV_SBI help This config allows kernel to use SBI v0.1 APIs. This will be deprecated in future once legacy M-mode software are no longer in use. config RISCV_BOOT_SPINWAIT bool "Spinwait booting method" depends on SMP default y help This enables support for booting Linux via spinwait method. In the spinwait method, all cores randomly jump to Linux. One of the cores gets chosen via lottery and all other keep spinning on a percpu variable. This method cannot support CPU hotplug and sparse hartid scheme. It should be only enabled for M-mode Linux or platforms relying on older firmware without SBI HSM extension. All other platforms should rely on ordered booting via SBI HSM extension which gets chosen dynamically at runtime if the firmware supports it. config KEXEC bool "Kexec system call" select KEXEC_CORE select HOTPLUG_CPU if SMP depends on MMU help kexec is a system call that implements the ability to shutdown your current kernel, and to start another kernel. It is like a reboot but it is independent of the system firmware. And like a reboot you can start any kernel with it, not just Linux. The name comes from the similarity to the exec system call. config KEXEC_FILE bool "kexec file based systmem call" select KEXEC_CORE select KEXEC_ELF select HAVE_IMA_KEXEC if IMA depends on 64BIT help This is new version of kexec system call. This system call is file based and takes file descriptors as system call argument for kernel and initramfs as opposed to list of segments as accepted by previous system call. If you don't know what to do here, say Y. config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE select BUILD_BIN2C depends on CRYPTO=y depends on CRYPTO_SHA256=y config CRASH_DUMP bool "Build kdump crash kernel" help Generate crash dump after being started by kexec. This should be normally only set in special crash dump kernels which are loaded in the main kernel with kexec-tools into a specially reserved region and then later executed after a crash by kdump/kexec. For more details see Documentation/admin-guide/kdump/kdump.rst config COMPAT bool "Kernel support for 32-bit U-mode" default 64BIT depends on 64BIT && MMU help This option enables support for a 32-bit U-mode running under a 64-bit kernel at S-mode. riscv32-specific components such as system calls, the user helper functions (vdso), signal rt_frame functions and the ptrace interface are handled appropriately by the kernel. If you want to execute 32-bit userspace applications, say Y. endmenu menu "Boot options" config CMDLINE string "Built-in kernel command line" help For most platforms, the arguments for the kernel's command line are provided at run-time, during boot. However, there are cases where either no arguments are being provided or the provided arguments are insufficient or even invalid. When that occurs, it is possible to define a built-in command line here and choose how the kernel should use it later on. choice prompt "Built-in command line usage" if CMDLINE != "" default CMDLINE_FALLBACK help Choose how the kernel will handle the provided built-in command line. config CMDLINE_FALLBACK bool "Use bootloader kernel arguments if available" help Use the built-in command line as fallback in case we get nothing during boot. This is the default behaviour. config CMDLINE_EXTEND bool "Extend bootloader kernel arguments" help The command-line arguments provided during boot will be appended to the built-in command line. This is useful in cases where the provided arguments are insufficient and you don't want to or cannot modify them. config CMDLINE_FORCE bool "Always use the default kernel command string" help Always use the built-in command line, even if we get one during boot. This is useful in case you need to override the provided command line on systems where you don't have or want control over it. endchoice config EFI_STUB bool config EFI bool "UEFI runtime support" depends on OF && !XIP_KERNEL select LIBFDT select UCS2_STRING select EFI_PARAMS_FROM_FDT select EFI_STUB select EFI_GENERIC_STUB select EFI_RUNTIME_WRAPPERS select RISCV_ISA_C depends on MMU default y help This option provides support for runtime services provided by UEFI firmware (such as non-volatile variables, realtime clock, and platform reset). A UEFI stub is also provided to allow the kernel to be booted as an EFI application. This is only useful on systems that have UEFI firmware. config CC_HAVE_STACKPROTECTOR_TLS def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) config STACKPROTECTOR_PER_TASK def_bool y depends on !RANDSTRUCT depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS config PHYS_RAM_BASE_FIXED bool "Explicitly specified physical RAM address" default n config PHYS_RAM_BASE hex "Platform Physical RAM address" depends on PHYS_RAM_BASE_FIXED default "0x80000000" help This is the physical address of RAM in the system. It has to be explicitly specified to run early relocations of read-write data from flash to RAM. config XIP_KERNEL bool "Kernel Execute-In-Place from ROM" depends on MMU && SPARSEMEM # This prevents XIP from being enabled by all{yes,mod}config, which # fail to build since XIP doesn't support large kernels. depends on !COMPILE_TEST select PHYS_RAM_BASE_FIXED help Execute-In-Place allows the kernel to run from non-volatile storage directly addressable by the CPU, such as NOR flash. This saves RAM space since the text section of the kernel is not loaded from flash to RAM. Read-write sections, such as the data section and stack, are still copied to RAM. The XIP kernel is not compressed since it has to run directly from flash, so it will take more space to store it. The flash address used to link the kernel object files, and for storing it, is configuration dependent. Therefore, if you say Y here, you must know the proper physical address where to store the kernel image depending on your own flash memory usage. Also note that the make target becomes "make xipImage" rather than "make zImage" or "make Image". The final kernel binary to put in ROM memory will be arch/riscv/boot/xipImage. SPARSEMEM is required because the kernel text and rodata that are flash resident are not backed by memmap, then any attempt to get a struct page on those regions will trigger a fault. If unsure, say N. config XIP_PHYS_ADDR hex "XIP Kernel Physical Location" depends on XIP_KERNEL default "0x21000000" help This is the physical address in your flash memory the kernel will be linked for and stored to. This address is dependent on your own flash usage. endmenu config BUILTIN_DTB bool depends on OF default y if XIP_KERNEL menu "Power management options" source "kernel/power/Kconfig" endmenu menu "CPU Power Management" source "drivers/cpuidle/Kconfig" endmenu source "arch/riscv/kvm/Kconfig"