From: Aurelien Jarno aurelien@aurel32.net
commit 6df2a016c0c8a3d0933ef33dd192ea6606b115e3 upstream.
From version 2.38, binutils default to ISA spec version 20191213. This
means that the csr read/write (csrr*/csrw*) instructions and fence.i instruction has separated from the `I` extension, become two standalone extensions: Zicsr and Zifencei. As the kernel uses those instruction, this causes the following build failure:
CC arch/riscv/kernel/vdso/vgettimeofday.o <<BUILDDIR>>/arch/riscv/include/asm/vdso/gettimeofday.h: Assembler messages: <<BUILDDIR>>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <<BUILDDIR>>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <<BUILDDIR>>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01' <<BUILDDIR>>/arch/riscv/include/asm/vdso/gettimeofday.h:71: Error: unrecognized opcode `csrr a5,0xc01'
The fix is to specify those extensions explicitely in -march. However as older binutils version do not support this, we first need to detect that.
Signed-off-by: Aurelien Jarno aurelien@aurel32.net Tested-by: Alexandre Ghiti alexandre.ghiti@canonical.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [Conor: converted to the 4.19 style of march string generation] Signed-off-by: Conor Dooley conor.dooley@microchip.com --- arch/riscv/Makefile | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -49,9 +49,16 @@ ifeq ($(CONFIG_RISCV_ISA_C),y) KBUILD_ARCH_C = c endif
-KBUILD_AFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)fd$(KBUILD_ARCH_C) +# Newer binutils versions default to ISA spec version 20191213 which moves some +# instructions from the I extension to the Zicsr and Zifencei extensions. +toolchain-need-zicsr-zifencei := $(call cc-option-yn, -march=$(riscv-march-y)_zicsr_zifencei) +ifeq ($(toolchain-need-zicsr-zifencei),y) + KBUILD_ARCH_ZISCR_ZIFENCEI = _zicsr_zifencei +endif + +KBUILD_AFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)fd$(KBUILD_ARCH_C)$(KBUILD_ARCH_ZISCR_ZIFENCEI)
-KBUILD_CFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)$(KBUILD_ARCH_C) +KBUILD_CFLAGS += -march=$(KBUILD_MARCH)$(KBUILD_ARCH_A)$(KBUILD_ARCH_C)$(KBUILD_ARCH_ZISCR_ZIFENCEI) KBUILD_CFLAGS += -mno-save-restore KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)