diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index abaf1ef1795c..1a134c9769f8 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -1,6 +1,9 @@ # SPDX-License-Identifier: GPL-2.0 source "arch/powerpc/platforms/Kconfig.cputype" +config CC_HAS_ELFV2 + def_bool PPC64 && $(cc-option, -mabi=elfv2) + config 32BIT bool default y if PPC32 @@ -586,6 +589,24 @@ config KEXEC_FILE config ARCH_HAS_KEXEC_PURGATORY def_bool KEXEC_FILE +config PPC64_BIG_ENDIAN_ELF_ABI_V2 + bool "Build big-endian kernel using ELF ABI V2 (EXPERIMENTAL)" + depends on PPC64 && CPU_BIG_ENDIAN + depends on CC_HAS_ELFV2 + depends on LD_IS_BFD && LD_VERSION >= 22400 + default n + help + This builds the kernel image using the "Power Architecture 64-Bit ELF + V2 ABI Specification", which has a reduced stack overhead and faster + function calls. This internal kernel ABI option does not affect + userspace compatibility. + + The V2 ABI is standard for 64-bit little-endian, but for big-endian + it is less well tested by kernel and toolchain. However some distros + build userspace this way, and it can produce a functioning kernel. + + This requires GCC and binutils 2.24 or newer. + config RELOCATABLE bool "Build a relocatable kernel" depends on PPC64 || (FLATMEM && (44x || PPC_85xx)) diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 7bac213b4125..9563336e3348 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -580,10 +580,10 @@ config CPU_LITTLE_ENDIAN endchoice config PPC64_ELF_ABI_V1 - def_bool PPC64 && CPU_BIG_ENDIAN + def_bool PPC64 && (CPU_BIG_ENDIAN && !PPC64_BIG_ENDIAN_ELF_ABI_V2) config PPC64_ELF_ABI_V2 - def_bool PPC64 && CPU_LITTLE_ENDIAN + def_bool PPC64 && !PPC64_ELF_ABI_V1 config PPC64_BOOT_WRAPPER def_bool n