select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
- select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_UBSAN
select ARCH_HAS_VDSO_DATA
select ARCH_KEEP_MEMBLOCK if ACPI
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
select HAVE_MOVE_PMD
select HAVE_MOVE_PUD
+ select HAVE_PAGE_SIZE_4KB
select HAVE_PCI
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
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))
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
+ # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
def_bool y
depends on $(as-instr, .option arch$(comma) +m)
affects irq stack size, which is equal to thread stack size.
config RISCV_MISALIGNED
- bool "Support misaligned load/store traps for kernel and userspace"
+ bool
select SYSCTL_ARCH_UNALIGN_ALLOW
- default y
help
- Say Y here if you want the kernel to embed support for misaligned
- load/store for both kernel and userspace. When disable, misaligned
- accesses will generate SIGBUS in userspace and panic in kernel.
+ Embed support for emulating misaligned loads and stores.
+
+choice
+ prompt "Unaligned Accesses Support"
+ default RISCV_PROBE_UNALIGNED_ACCESS
+ help
+ This determines the level of support for unaligned accesses. This
+ information is used by the kernel to perform optimizations. It is also
+ exposed to user space via the hwprobe syscall. The hardware will be
+ probed at boot by default.
+
+config RISCV_PROBE_UNALIGNED_ACCESS
+ bool "Probe for hardware unaligned access support"
+ select RISCV_MISALIGNED
+ help
+ During boot, the kernel will run a series of tests to determine the
+ speed of unaligned accesses. This probing will dynamically determine
+ the speed of unaligned accesses on the underlying system. If unaligned
+ memory accesses trap into the kernel as they are not supported by the
+ system, the kernel will emulate the unaligned accesses to preserve the
+ UABI.
+
+config RISCV_EMULATED_UNALIGNED_ACCESS
+ bool "Emulate unaligned access where system support is missing"
+ select RISCV_MISALIGNED
+ help
+ If unaligned memory accesses trap into the kernel as they are not
+ supported by the system, the kernel will emulate the unaligned
+ accesses to preserve the UABI. When the underlying system does support
+ unaligned accesses, the unaligned accesses are assumed to be slow.
+
+config RISCV_SLOW_UNALIGNED_ACCESS
+ bool "Assume the system supports slow unaligned memory accesses"
+ depends on NONPORTABLE
+ help
+ Assume that the system supports slow unaligned memory accesses. The
+ kernel and userspace programs may not be able to run at all on systems
+ that do not support unaligned memory accesses.
config RISCV_EFFICIENT_UNALIGNED_ACCESS
- bool "Assume the CPU supports fast unaligned memory accesses"
+ bool "Assume the system supports fast unaligned memory accesses"
depends on NONPORTABLE
select DCACHE_WORD_ACCESS if MMU
select HAVE_EFFICIENT_UNALIGNED_ACCESS
help
- Say Y here if you want the kernel to assume that the CPU supports
- efficient unaligned memory accesses. When enabled, this option
- improves the performance of the kernel on such CPUs. However, the
- kernel will run much more slowly, or will not be able to run at all,
- on CPUs that do not support efficient unaligned memory accesses.
+ Assume that the system supports fast unaligned memory accesses. When
+ enabled, this option improves the performance of the kernel on such
+ systems. However, the kernel and userspace programs will run much more
+ slowly, or will not be able to run at all, on systems that do not
+ support efficient unaligned memory accesses.
- If unsure what to do here, say N.
+endchoice
endmenu # "Platform type"
def_bool y
config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
- def_bool CRASH_CORE
+ def_bool CRASH_RESERVE
config COMPAT
bool "Kernel support for 32-bit U-mode"
config BUILTIN_DTB
bool "Built-in device tree"
depends on OF && NONPORTABLE
- default y if XIP_KERNEL
+ help
+ Build a device tree into the Linux image.
+ This option should be selected if no bootloader is being used.
+ If unsure, say N.
+
+
+config BUILTIN_DTB_SOURCE
+ string "Built-in device tree source"
+ depends on BUILTIN_DTB
+ help
+ DTS file path (without suffix, relative to arch/riscv/boot/dts)
+ for the DTS file that will be used to produce the DTB linked into the
+ kernel.
endmenu # "Boot options"
projects / linux-2.6-microblaze.git / blobdiff