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Diffstat (limited to 'arch/riscv/Kconfig')
| -rw-r--r-- | arch/riscv/Kconfig | 928 |
1 files changed, 928 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig new file mode 100644 index 0000000000..9e6d442773 --- /dev/null +++ b/arch/riscv/Kconfig @@ -0,0 +1,928 @@ +# 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 ACPI_GENERIC_GSI if ACPI + select ACPI_REDUCED_HARDWARE_ONLY if ACPI + select ARCH_DMA_DEFAULT_COHERENT + select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION + select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 + select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE + select ARCH_HAS_BINFMT_FLAT + select ARCH_HAS_CURRENT_STACK_POINTER + select ARCH_HAS_DEBUG_VIRTUAL if MMU + select ARCH_HAS_DEBUG_VM_PGTABLE + 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_NON_OVERLAPPING_ADDRESS_SPACE + select ARCH_HAS_PMEM_API + 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_SYSCALL_WRAPPER + select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST + select ARCH_HAS_UBSAN_SANITIZE_ALL + select ARCH_HAS_VDSO_DATA + 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_CFI_CLANG + select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU + select ARCH_SUPPORTS_HUGETLBFS if MMU + select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU + select ARCH_SUPPORTS_PER_VMA_LOCK if MMU + select ARCH_USE_MEMTEST + select ARCH_USE_QUEUED_RWLOCKS + select ARCH_USES_CFI_TRAPS if CFI_CLANG + select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU + select ARCH_WANT_FRAME_POINTERS + select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT + select ARCH_WANT_HUGE_PMD_SHARE if 64BIT + select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL + select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP + select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE + select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU + select BUILDTIME_TABLE_SORT if MMU + select CLINT_TIMER if !MMU + select CLONE_BACKWARDS + select COMMON_CLK + select CPU_PM if CPU_IDLE || HIBERNATION + select EDAC_SUPPORT + select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) + select GENERIC_ARCH_TOPOLOGY + select GENERIC_ATOMIC64 if !64BIT + select GENERIC_CLOCKEVENTS_BROADCAST if SMP + select GENERIC_EARLY_IOREMAP + select GENERIC_ENTRY + select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO + select GENERIC_IDLE_POLL_SETUP + select GENERIC_IOREMAP if MMU + select GENERIC_IRQ_IPI if SMP + select GENERIC_IRQ_IPI_MUX if SMP + 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 HARDIRQS_SW_RESEND + select HAS_IOPORT if MMU + select HAVE_ARCH_AUDITSYSCALL + select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP + select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL + 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_THREAD_STRUCT_WHITELIST + select HAVE_ARCH_TRACEHOOK + select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU + select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD + select HAVE_ARCH_VMAP_STACK if MMU && 64BIT + select HAVE_ASM_MODVERSIONS + select HAVE_CONTEXT_TRACKING_USER + select HAVE_DEBUG_KMEMLEAK + select HAVE_DMA_CONTIGUOUS if MMU + select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) + 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_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER + select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION + select HAVE_EBPF_JIT if MMU + select HAVE_FUNCTION_ARG_ACCESS_API + 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 + # https://github.com/ClangBuiltLinux/linux/issues/1881 + select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD + 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_POSIX_CPU_TIMERS_TASK_WORK + select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL + select HAVE_REGS_AND_STACK_ACCESS_API + select HAVE_RETHOOK if !XIP_KERNEL + select HAVE_RSEQ + select HAVE_STACKPROTECTOR + select HAVE_SYSCALL_TRACEPOINTS + select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU + select IRQ_DOMAIN + select IRQ_FORCED_THREADING + select KASAN_VMALLOC if KASAN + select LOCK_MM_AND_FIND_VMA + 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_ALTERNATIVE if !XIP_KERNEL + select RISCV_INTC + select RISCV_TIMER if RISCV_SBI + select SIFIVE_PLIC + 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 CLANG_SUPPORTS_DYNAMIC_FTRACE + def_bool CC_IS_CLANG + # https://github.com/llvm/llvm-project/commit/6ab8927931851bb42b2c93a00801dc499d7d9b1e + depends on CLANG_VERSION >= 130000 + # https://github.com/ClangBuiltLinux/linux/issues/1817 + depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) + +config GCC_SUPPORTS_DYNAMIC_FTRACE + def_bool CC_IS_GCC + depends on $(cc-option,-fpatchable-function-entry=8) + +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 && MMU + default 0x80000000 if !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 + +config RISCV_DMA_NONCOHERENT + bool + select ARCH_HAS_DMA_PREP_COHERENT + select ARCH_HAS_SETUP_DMA_OPS + select ARCH_HAS_SYNC_DMA_FOR_CPU + select ARCH_HAS_SYNC_DMA_FOR_DEVICE + select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB + +config RISCV_NONSTANDARD_CACHE_OPS + bool + help + This enables function pointer support for non-standard noncoherent + systems to handle cache management. + +config AS_HAS_INSN + def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) + +config AS_HAS_OPTION_ARCH + # https://reviews.llvm.org/D123515 + def_bool y + depends on $(as-instr, .option arch$(comma) +m) + depends on !$(as-instr, .option arch$(comma) -i) + +source "arch/riscv/Kconfig.socs" +source "arch/riscv/Kconfig.errata" + +menu "Platform type" + +config NONPORTABLE + bool "Allow configurations that result in non-portable kernels" + help + RISC-V kernel binaries are compatible between all known systems + whenever possible, but there are some use cases that can only be + satisfied by configurations that result in kernel binaries that are + not portable between systems. + + Selecting N does not guarantee kernels will be portable to all known + systems. Selecting any of the options guarded by NONPORTABLE will + result in kernel binaries that are unlikely to be portable between + systems. + + If unsure, say N. + +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" + depends on NONPORTABLE + select 32BIT + select GENERIC_LIB_ASHLDI3 + select GENERIC_LIB_ASHRDI3 + select GENERIC_LIB_LSHRDI3 + select GENERIC_LIB_UCMPDI2 + +config ARCH_RV64I + bool "RV64I" + select 64BIT + select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 + 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 SCHED_MC + bool "Multi-core scheduler support" + depends on SMP + help + Multi-core scheduler support improves the CPU scheduler's decision + making when dealing with multi-core CPU chips at a cost of slightly + increased overhead in some places. If unsure say N here. + +config NR_CPUS + int "Maximum number of CPUs (2-512)" + depends on SMP + range 2 512 if !RISCV_SBI_V01 + range 2 32 if RISCV_SBI_V01 && 32BIT + range 2 64 if RISCV_SBI_V01 && 64BIT + default "32" if 32BIT + default "64" if 64BIT + +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 ARCH_SUPPORTS_NUMA_BALANCING + select GENERIC_ARCH_NUMA + select NEED_PER_CPU_EMBED_FIRST_CHUNK + select OF_NUMA + select USE_PERCPU_NUMA_NODE_ID + 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 + erratum or cpufeature required by the execution platform at run + time. The code patching overhead is minimal, as it's only done + once at boot and once on each module load. + +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_SVNAPOT + bool "Svnapot extension support for supervisor mode NAPOT pages" + depends on 64BIT && MMU + depends on RISCV_ALTERNATIVE + default y + help + Allow kernel to detect the Svnapot ISA-extension dynamically at boot + time and enable its usage. + + The Svnapot extension is used to mark contiguous PTEs as a range + of contiguous virtual-to-physical translations for a naturally + aligned power-of-2 (NAPOT) granularity larger than the base 4KB page + size. When HUGETLBFS is also selected this option unconditionally + allocates some memory for each NAPOT page size supported by the kernel. + When optimizing for low memory consumption and for platforms without + the Svnapot extension, it may be better to say N here. + + If you don't know what to do here, say Y. + +config RISCV_ISA_SVPBMT + bool "Svpbmt extension support for supervisor mode page-based memory types" + depends on 64BIT && MMU + depends on RISCV_ALTERNATIVE + default y + help + Adds support to dynamically detect the presence of the Svpbmt + ISA-extension (Supervisor-mode: page-based memory types) and + enable its usage. + + The memory type for a page contains a combination of attributes + that indicate the cacheability, idempotency, and ordering + properties for access to that page. + + The Svpbmt extension is only available on 64-bit cpus. + + If you don't know what to do here, say Y. + +config TOOLCHAIN_HAS_V + bool + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64iv) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32iv) + depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 + depends on AS_HAS_OPTION_ARCH + +config RISCV_ISA_V + bool "VECTOR extension support" + depends on TOOLCHAIN_HAS_V + depends on FPU + select DYNAMIC_SIGFRAME + default y + help + Say N here if you want to disable all vector related procedure + in the kernel. + + If you don't know what to do here, say Y. + +config RISCV_ISA_V_DEFAULT_ENABLE + bool "Enable userspace Vector by default" + depends on RISCV_ISA_V + default y + help + Say Y here if you want to enable Vector in userspace by default. + Otherwise, userspace has to make explicit prctl() call to enable + Vector, or enable it via the sysctl interface. + + If you don't know what to do here, say Y. + +config TOOLCHAIN_HAS_ZBB + bool + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) + depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 + depends on AS_HAS_OPTION_ARCH + +config RISCV_ISA_ZBB + bool "Zbb extension support for bit manipulation instructions" + depends on TOOLCHAIN_HAS_ZBB + depends on MMU + depends on RISCV_ALTERNATIVE + default y + help + Adds support to dynamically detect the presence of the ZBB + extension (basic bit manipulation) and enable its usage. + + The Zbb extension provides instructions to accelerate a number + of bit-specific operations (count bit population, sign extending, + bitrotation, etc). + + If you don't know what to do here, say Y. + +config RISCV_ISA_ZICBOM + bool "Zicbom extension support for non-coherent DMA operation" + depends on MMU + depends on RISCV_ALTERNATIVE + default y + select RISCV_DMA_NONCOHERENT + select DMA_DIRECT_REMAP + help + Adds support to dynamically detect the presence of the ZICBOM + extension (Cache Block Management Operations) and enable its + usage. + + The Zicbom extension can be used to handle for example + non-coherent DMA support on devices that need it. + + If you don't know what to do here, say Y. + +config RISCV_ISA_ZICBOZ + bool "Zicboz extension support for faster zeroing of memory" + depends on MMU + depends on RISCV_ALTERNATIVE + default y + help + Enable the use of the Zicboz extension (cbo.zero instruction) + when available. + + The Zicboz extension is used for faster zeroing of memory. + + If you don't know what to do here, say Y. + +config TOOLCHAIN_HAS_ZIHINTPAUSE + bool + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause) + depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600 + +config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI + def_bool y + # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc + # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd + depends on AS_IS_GNU && AS_VERSION >= 23600 + help + Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer + 20191213 version, which moves some instructions from the I extension to + the Zicsr and Zifencei extensions. This requires explicitly specifying + Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr + and Zifencei are supported in binutils from version 2.36 onwards. + To make life easier, and avoid forcing toolchains that default to a + newer ISA spec to version 2.2, relax the check to binutils >= 2.36. + For clang < 17 or GCC < 11.3.0, for which this is not possible or need + special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. + +config TOOLCHAIN_NEEDS_OLD_ISA_SPEC + def_bool y + depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI + # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 + # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 + depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) + help + Certain versions of clang and GCC do not support zicsr and zifencei via + -march. This option causes an older ISA spec compatible with these older + versions of clang and GCC to be passed to GAS, which has the same result + as passing zicsr and zifencei to -march. + +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. + +config IRQ_STACKS + bool "Independent irq & softirq stacks" if EXPERT + default y + select HAVE_IRQ_EXIT_ON_IRQ_STACK + select HAVE_SOFTIRQ_ON_OWN_STACK + help + Add independent irq & softirq stacks for percpu to prevent kernel stack + overflows. We may save some memory footprint by disabling IRQ_STACKS. + +config THREAD_SIZE_ORDER + int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT + range 0 4 + default 1 if 32BIT && !KASAN + default 3 if 64BIT && KASAN + default 2 + help + Specify the Pages of thread stack size (from 4KB to 64KB), which also + affects irq stack size, which is equal to thread stack size. + +endmenu # "Platform type" + +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 if RISCV_SBI_V01 || RISCV_M_MODE + 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. + + Since spinwait is incompatible with sparse hart IDs, it requires + NR_CPUS be large enough to contain the physical hart ID of the first + hart to enter Linux. + + If unsure what to do here, say N. + +config ARCH_SUPPORTS_KEXEC + def_bool y + +config ARCH_SELECTS_KEXEC + def_bool y + depends on KEXEC + select HOTPLUG_CPU if SMP + +config ARCH_SUPPORTS_KEXEC_FILE + def_bool 64BIT + +config ARCH_SELECTS_KEXEC_FILE + def_bool y + depends on KEXEC_FILE + select HAVE_IMA_KEXEC if IMA + select KEXEC_ELF + +config ARCH_SUPPORTS_KEXEC_PURGATORY + def_bool ARCH_SUPPORTS_KEXEC_FILE + +config ARCH_SUPPORTS_CRASH_DUMP + def_bool y + +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. + +config RELOCATABLE + bool "Build a relocatable kernel" + depends on MMU && 64BIT && !XIP_KERNEL + help + This builds a kernel as a Position Independent Executable (PIE), + which retains all relocation metadata required to relocate the + kernel binary at runtime to a different virtual address than the + address it was linked at. + Since RISCV uses the RELA relocation format, this requires a + relocation pass at runtime even if the kernel is loaded at the + same address it was linked at. + + If unsure, say N. + +config RANDOMIZE_BASE + bool "Randomize the address of the kernel image" + select RELOCATABLE + depends on MMU && 64BIT && !XIP_KERNEL + help + Randomizes the virtual address at which the kernel image is + loaded, as a security feature that deters exploit attempts + relying on knowledge of the location of kernel internals. + + It is the bootloader's job to provide entropy, by passing a + random u64 value in /chosen/kaslr-seed at kernel entry. + + When booting via the UEFI stub, it will invoke the firmware's + EFI_RNG_PROTOCOL implementation (if available) to supply entropy + to the kernel proper. In addition, it will randomise the physical + location of the kernel Image as well. + + If unsure, say N. + +endmenu # "Kernel features" + +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 + depends on MMU + default y + select ARCH_SUPPORTS_ACPI if 64BIT + select EFI_GENERIC_STUB + select EFI_PARAMS_FROM_FDT + select EFI_RUNTIME_WRAPPERS + select EFI_STUB + select LIBFDT + select RISCV_ISA_C + select UCS2_STRING + 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" + depends on NONPORTABLE + 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 && NONPORTABLE + # 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. + +config RISCV_ISA_FALLBACK + bool "Permit falling back to parsing riscv,isa for extension support by default" + default y + help + Parsing the "riscv,isa" devicetree property has been deprecated and + replaced by a list of explicitly defined strings. For compatibility + with existing platforms, the kernel will fall back to parsing the + "riscv,isa" property if the replacements are not found. + + Selecting N here will result in a kernel that does not use the + fallback, unless the commandline "riscv_isa_fallback" parameter is + present. + + Please see the dt-binding, located at + Documentation/devicetree/bindings/riscv/extensions.yaml for details + on the replacement properties, "riscv,isa-base" and + "riscv,isa-extensions". + +endmenu # "Boot options" + +config BUILTIN_DTB + bool + depends on OF && NONPORTABLE + default y if XIP_KERNEL + +config PORTABLE + bool + default !NONPORTABLE + select EFI + select MMU + select OF + +menu "Power management options" + +source "kernel/power/Kconfig" + +# Hibernation is only possible on systems where the SBI implementation has +# marked its reserved memory as not accessible from, or does not run +# from the same memory as, Linux +config ARCH_HIBERNATION_POSSIBLE + def_bool NONPORTABLE + +config ARCH_HIBERNATION_HEADER + def_bool HIBERNATION + +config ARCH_SUSPEND_POSSIBLE + def_bool y + +endmenu # "Power management options" + +menu "CPU Power Management" + +source "drivers/cpuidle/Kconfig" + +source "drivers/cpufreq/Kconfig" + +endmenu # "CPU Power Management" + +source "arch/riscv/kvm/Kconfig" + +source "drivers/acpi/Kconfig" |