path: root/arch/powerpc/Kconfig

# SPDX-License-Identifier: GPL-2.0
source "arch/powerpc/platforms/Kconfig.cputype"

config CC_HAS_ELFV2
	def_bool PPC64 && $(cc-option, -mabi=elfv2)

config CC_HAS_PREFIXED
	def_bool PPC64 && $(cc-option, -mcpu=power10 -mprefixed)

config CC_HAS_PCREL
	# Clang has a bug (https://github.com/llvm/llvm-project/issues/62372)
	# where pcrel code is not generated if -msoft-float, -mno-altivec, or
	# -mno-vsx options are also given. Without these options, fp/vec
	# instructions are generated from regular kernel code. So Clang can't
	# do pcrel yet.
	def_bool PPC64 && CC_IS_GCC && $(cc-option, -mcpu=power10 -mpcrel)

config 32BIT
	bool
	default y if PPC32

config 64BIT
	bool
	default y if PPC64

config LIVEPATCH_64
	def_bool PPC64
	depends on LIVEPATCH

config MMU
	bool
	default y

config ARCH_MMAP_RND_BITS_MAX
	# On Book3S 64, the default virtual address space for 64-bit processes
	# is 2^47 (128TB). As a maximum, allow randomisation to consume up to
	# 32T of address space (2^45), which should ensure a reasonable gap
	# between bottom-up and top-down allocations for applications that
	# consume "normal" amounts of address space. Book3S 64 only supports 64K
	# and 4K page sizes.
	default 29 if PPC_BOOK3S_64 && PPC_64K_PAGES # 29 = 45 (32T) - 16 (64K)
	default 33 if PPC_BOOK3S_64		     # 33 = 45 (32T) - 12 (4K)
	#
	# On all other 64-bit platforms (currently only Book3E), the virtual
	# address space is 2^46 (64TB). Allow randomisation to consume up to 16T
	# of address space (2^44). Only 4K page sizes are supported.
	default 32 if 64BIT	# 32 = 44 (16T) - 12 (4K)
	#
	# For 32-bit, use the compat values, as they're the same.
	default ARCH_MMAP_RND_COMPAT_BITS_MAX

config ARCH_MMAP_RND_BITS_MIN
	# Allow randomisation to consume up to 1GB of address space (2^30).
	default 14 if 64BIT && PPC_64K_PAGES	# 14 = 30 (1GB) - 16 (64K)
	default 18 if 64BIT			# 18 = 30 (1GB) - 12 (4K)
	#
	# For 32-bit, use the compat values, as they're the same.
	default ARCH_MMAP_RND_COMPAT_BITS_MIN

config ARCH_MMAP_RND_COMPAT_BITS_MAX
	# Total virtual address space for 32-bit processes is 2^31 (2GB).
	# Allow randomisation to consume up to 512MB of address space (2^29).
	default 11 if PPC_256K_PAGES	# 11 = 29 (512MB) - 18 (256K)
	default 13 if PPC_64K_PAGES	# 13 = 29 (512MB) - 16 (64K)
	default 15 if PPC_16K_PAGES	# 15 = 29 (512MB) - 14 (16K)
	default 17			# 17 = 29 (512MB) - 12 (4K)

config ARCH_MMAP_RND_COMPAT_BITS_MIN
	# Total virtual address space for 32-bit processes is 2^31 (2GB).
	# Allow randomisation to consume up to 8MB of address space (2^23).
	default 5 if PPC_256K_PAGES	#  5 = 23 (8MB) - 18 (256K)
	default 7 if PPC_64K_PAGES	#  7 = 23 (8MB) - 16 (64K)
	default 9 if PPC_16K_PAGES	#  9 = 23 (8MB) - 14 (16K)
	default 11			# 11 = 23 (8MB) - 12 (4K)

config NR_IRQS
	int "Number of virtual interrupt numbers"
	range 32 1048576
	default "512"
	help
	  This defines the number of virtual interrupt numbers the kernel
	  can manage. Virtual interrupt numbers are what you see in
	  /proc/interrupts. If you configure your system to have too few,
	  drivers will fail to load or worse - handle with care.

config NMI_IPI