Quelle  Makefile

# SPDX-License-Identifier: GPL-2.0
java.lang.NullPointerException
# Author: Huacai Chen <chenhuacai@loongson.cn>
# Copyright (C) 2020-2022 Loongson Technology Corporation Limited

boot := arch/loongarch/boot

KBUILD_DEFCONFIG := loongson3_defconfig
KBUILD_DTBS      := dtbs

image-name-y   := vmlinux
image-name-$(CONFIG_EFI_ZBOOT) := vmlinuz

ifndef CONFIG_EFI_STUB
KBUILD_IMAGE := $(boot)/vmlinux.elf
else
KBUILD_IMAGE := $(boot)/$(image-name-y).efi
endif

java.lang.NullPointerException
# Select the object file format to substitute into the linker script.
java.lang.NullPointerException
64bit-tool-archpref = loongarch64
32bit-bfd  = elf32-loongarch
64bit-bfd  = elf64-loongarch
32bit-emul  = elf32loongarch
64bit-emul  = elf64loongarch

CC_FLAGS_FPU  := -mfpu=64
CC_FLAGS_NO_FPU  := -msoft-float

ifdef CONFIG_UNWINDER_ORC
orc_hash_h := arch/$(SRCARCH)/include/generated/asm/orc_hash.h
orc_hash_sh := $(srctree)/scripts/orc_hash.sh
targets += $(orc_hash_h)
quiet_cmd_orc_hash = GEN     $@
      cmd_orc_hash = mkdir -p $(dir $@); \
       $(CONFIG_SHELL) $(orc_hash_sh) < $< > $@
$(orc_hash_h): $(srctree)/arch/loongarch/include/asm/orc_types.h $(orc_hash_sh) FORCE
 $(call if_changed,orc_hash)
archprepare: $(orc_hash_h)
endif

ifdef CONFIG_DYNAMIC_FTRACE
KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
CC_FLAGS_FTRACE := -fpatchable-function-entry=2
endif

ifdef CONFIG_64BIT
tool-archpref  = $(64bit-tool-archpref)
UTS_MACHINE  := loongarch64
endif

ifneq ($(SUBARCH),$(ARCH))
  ifeq ($(CROSS_COMPILE),)
    CROSS_COMPILE := $(call cc-cross-prefix, $(tool-archpref)-linux-  $(tool-archpref)-linux-gnu-  $(tool-archpref)-unknown-linux-gnu-)
  endif
endif

ifdef CONFIG_64BIT
ld-emul   = $(64bit-emul)
cflags-y  += -mabi=lp64s -mcmodel=normal
endif

cflags-y   += -pipe $(CC_FLAGS_NO_FPU)
LDFLAGS_vmlinux   += -static -n -nostdlib

# When the assembler supports explicit relocation hint, we must use it.
# GCC may have -mexplicit-relocs off by default if it was built with an old
# assembler, so we force it via an option.
java.lang.NullPointerException
# When the assembler does not supports explicit relocation hint, we can't use
# it.  Disable it if the compiler supports it.
java.lang.NullPointerException
# The combination of a "new" assembler and "old" GCC is not supported, given
# the rarity of this combo and the extra complexity needed to make it work.
# Either upgrade the compiler or downgrade the assembler; the build will error
# out if it is the case (by probing for the model attribute; all supported
# compilers in this case would have support).
java.lang.NullPointerException
# Also, -mdirect-extern-access is useful in case of building with explicit
# relocs, for avoiding unnecessary GOT accesses. It is harmless to not have
# support though.
ifdef CONFIG_AS_HAS_EXPLICIT_RELOCS
cflags-y   += $(call cc-option,-mexplicit-relocs)
KBUILD_CFLAGS_KERNEL  += $(call cc-option,-mdirect-extern-access)
KBUILD_CFLAGS_KERNEL  += $(call cc-option,-fdirect-access-external-data)
KBUILD_AFLAGS_MODULE  += $(call cc-option,-fno-direct-access-external-data)
KBUILD_CFLAGS_MODULE  += $(call cc-option,-fno-direct-access-external-data)
else
cflags-y   += $(call cc-option,-mno-explicit-relocs)
KBUILD_AFLAGS_KERNEL  += -Wa,-mla-global-with-pcrel
KBUILD_CFLAGS_KERNEL  += -Wa,-mla-global-with-pcrel
KBUILD_AFLAGS_MODULE  += -Wa,-mla-global-with-abs
KBUILD_CFLAGS_MODULE  += -fplt -Wa,-mla-global-with-abs,-mla-local-with-abs
endif

KBUILD_AFLAGS   += $(call cc-option,-mno-relax) $(call cc-option,-Wa$(comma)-mno-relax)
KBUILD_CFLAGS   += $(call cc-option,-mno-relax) $(call cc-option,-Wa$(comma)-mno-relax)
KBUILD_AFLAGS   += $(call cc-option,-mthin-add-sub) $(call cc-option,-Wa$(comma)-mthin-add-sub)
KBUILD_CFLAGS   += $(call cc-option,-mthin-add-sub) $(call cc-option,-Wa$(comma)-mthin-add-sub)

ifdef CONFIG_OBJTOOL
ifdef CONFIG_CC_HAS_ANNOTATE_TABLEJUMP
KBUILD_CFLAGS   += -mannotate-tablejump
else
KBUILD_CFLAGS   += -fno-jump-tables # keep compatibility with older compilers
endif
ifdef CONFIG_RUSTC_HAS_ANNOTATE_TABLEJUMP
KBUILD_RUSTFLAGS  += -Cllvm-args=--loongarch-annotate-tablejump
else
KBUILD_RUSTFLAGS  += -Zno-jump-tables # keep compatibility with older compilers
endif
ifdef CONFIG_LTO_CLANG
# The annotate-tablejump option can not be passed to LLVM backend when LTO is enabled.
# Ensure it is aware of linker with LTO, '--loongarch-annotate-tablejump' also needs to
# be passed via '-mllvm' to ld.lld.
KBUILD_LDFLAGS   += $(call ld-option,-mllvm --loongarch-annotate-tablejump)
endif
endif

KBUILD_RUSTFLAGS  += --target=loongarch64-unknown-none-softfloat -Ccode-model=small
KBUILD_RUSTFLAGS_KERNEL  += -Zdirect-access-external-data=yes
KBUILD_RUSTFLAGS_MODULE  += -Zdirect-access-external-data=no

ifeq ($(CONFIG_RELOCATABLE),y)
KBUILD_CFLAGS_KERNEL  += -fPIE
KBUILD_RUSTFLAGS_KERNEL  += -Crelocation-model=pie
LDFLAGS_vmlinux   += -static -pie --no-dynamic-linker -z notext $(call ld-option, --apply-dynamic-relocs)
endif

cflags-y += $(call cc-option, -mno-check-zero-division -fno-isolate-erroneous-paths-dereference)

ifndef CONFIG_KASAN
cflags-y += -fno-builtin-memcpy -fno-builtin-memmove -fno-builtin-memset
endif

load-y  = 0x9000000000200000
bootvars-y = VMLINUX_LOAD_ADDRESS=$(load-y)

drivers-$(CONFIG_PCI)  += arch/loongarch/pci/

KBUILD_AFLAGS += $(cflags-y)
KBUILD_CFLAGS += $(cflags-y)
KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y)

# This is required to get dwarf unwinding tables into .debug_frame
# instead of .eh_frame so we don't discard them.
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables

ifdef CONFIG_ARCH_STRICT_ALIGN
# Don't emit unaligned accesses.
# Not all LoongArch cores support unaligned access, and as kernel we can't
# rely on others to provide emulation for these accesses.
KBUILD_CFLAGS += $(call cc-option,-mstrict-align)
else
# Optimise for performance on hardware supports unaligned access.
KBUILD_CFLAGS += $(call cc-option,-mno-strict-align)
endif

KBUILD_CFLAGS += -isystem $(shell $(CC) -print-file-name=include)

KBUILD_LDFLAGS += -m $(ld-emul)

ifdef need-compiler
CHECKFLAGS += $(shell $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
 grep -E -vw '__GNUC_(MINOR_|PATCHLEVEL_)?_' | \
 sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g')
endif

libs-y += arch/loongarch/lib/
libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a

drivers-y  += arch/loongarch/crypto/

# suspend and hibernation support
drivers-$(CONFIG_PM) += arch/loongarch/power/

ifeq ($(KBUILD_EXTMOD),)
prepare: vdso_prepare
vdso_prepare: prepare0
 $(Q)$(MAKE) $(build)=arch/loongarch/vdso include/generated/vdso-offsets.h
endif

vdso-install-y += arch/loongarch/vdso/vdso.so.dbg

all: $(notdir $(KBUILD_IMAGE)) $(KBUILD_DTBS)

vmlinuz.efi: vmlinux.efi

vmlinux.elf vmlinux.efi vmlinuz.efi: vmlinux
 $(Q)$(MAKE) $(build)=$(boot) $(bootvars-y) $(boot)/$@

install:
 $(call cmd,install)

define archhelp
 echo '  vmlinux.elf    - Uncompressed ELF kernel image (arch/loongarch/boot/vmlinux.elf)'
 echo '  vmlinux.efi    - Uncompressed EFI kernel image (arch/loongarch/boot/vmlinux.efi)'
 echo '  vmlinuz.efi    - GZIP/ZSTD-compressed EFI kernel image (arch/loongarch/boot/vmlinuz.efi)'
 echo '                   Default when CONFIG_EFI_ZBOOT=y'
 echo '  install        - Install kernel using (your) ~/bin/$(INSTALLKERNEL) or'
 echo '                   (distribution) /sbin/$(INSTALLKERNEL) or install.sh to $$(INSTALL_PATH)'
 echo
endef