Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) # SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) # The stub may be linked into the kernel proper or into a separate boot binary,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4) # but in either case, it executes before the kernel does (with MMU disabled) so
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5) # things like ftrace and stack-protector are likely to cause trouble if left
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) # enabled, even if doing so doesn't break the build.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) cflags-$(CONFIG_X86_32)		:= -march=i386
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) cflags-$(CONFIG_X86_64)		:= -mcmodel=small
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) cflags-$(CONFIG_X86)		+= -m$(BITS) -D__KERNEL__ \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) 				   -fPIC -fno-strict-aliasing -mno-red-zone \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) 				   -mno-mmx -mno-sse -fshort-wchar \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) 				   -Wno-pointer-sign \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 				   $(call cc-disable-warning, address-of-packed-member) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) 				   $(call cc-disable-warning, gnu) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 				   -fno-asynchronous-unwind-tables \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) 				   $(CLANG_FLAGS)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) # arm64 uses the full KBUILD_CFLAGS so it's necessary to explicitly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) # disable the stackleak plugin
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) cflags-$(CONFIG_ARM64)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 				   -fpie $(DISABLE_STACKLEAK_PLUGIN) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 				   $(call cc-option,-mbranch-protection=none)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) cflags-$(CONFIG_ARM)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 				   -fno-builtin -fpic \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 				   $(call cc-option,-mno-single-pic-base)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) cflags-$(CONFIG_RISCV)		:= $(subst $(CC_FLAGS_FTRACE),,$(KBUILD_CFLAGS)) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 				   -fpic
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) cflags-$(CONFIG_EFI_GENERIC_STUB) += -I$(srctree)/scripts/dtc/libfdt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) KBUILD_CFLAGS			:= $(cflags-y) -Os -DDISABLE_BRANCH_PROFILING \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 				   -include $(srctree)/include/linux/hidden.h \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 				   -D__NO_FORTIFY \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 				   -ffreestanding \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 				   -fno-stack-protector \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 				   $(call cc-option,-fno-addrsig) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 				   -D__DISABLE_EXPORTS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) # remove SCS flags from all objects in this directory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) # disable LTO
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO), $(KBUILD_CFLAGS))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) GCOV_PROFILE			:= n
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) # Sanitizer runtimes are unavailable and cannot be linked here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) KASAN_SANITIZE			:= n
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) KCSAN_SANITIZE			:= n
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) UBSAN_SANITIZE			:= n
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) OBJECT_FILES_NON_STANDARD	:= y
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) KCOV_INSTRUMENT			:= n
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) lib-y				:= efi-stub-helper.o gop.o secureboot.o tpm.o \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 				   file.o mem.o random.o randomalloc.o pci.o \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 				   skip_spaces.o lib-cmdline.o lib-ctype.o \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 				   alignedmem.o relocate.o vsprintf.o
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) # include the stub's generic dependencies from lib/ when building for ARM/arm64
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) efi-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	$(call if_changed_rule,cc_o_c)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) lib-$(CONFIG_EFI_GENERIC_STUB)	+= efi-stub.o fdt.o string.o \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 				   $(patsubst %.c,lib-%.o,$(efi-deps-y))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) lib-$(CONFIG_ARM)		+= arm32-stub.o
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) lib-$(CONFIG_ARM64)		+= arm64-stub.o
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) lib-$(CONFIG_X86)		+= x86-stub.o
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) lib-$(CONFIG_RISCV)		+= riscv-stub.o
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) CFLAGS_arm32-stub.o		:= -DTEXT_OFFSET=$(TEXT_OFFSET)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) # Even when -mbranch-protection=none is set, Clang will generate a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) # .note.gnu.property for code-less object files (like lib/ctype.c),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) # so work around this by explicitly removing the unwanted section.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) # https://bugs.llvm.org/show_bug.cgi?id=46480
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) STUBCOPY_FLAGS-y		+= --remove-section=.note.gnu.property
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) # For x86, bootloaders like systemd-boot or grub-efi do not zero-initialize the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) # .bss section, so the .bss section of the EFI stub needs to be included in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) # .data section of the compressed kernel to ensure initialization. Rename the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) # .bss section here so it's easy to pick out in the linker script.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) STUBCOPY_FLAGS-$(CONFIG_X86)	+= --rename-section .bss=.bss.efistub,load,alloc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) STUBCOPY_RELOC-$(CONFIG_X86_32)	:= R_386_32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) STUBCOPY_RELOC-$(CONFIG_X86_64)	:= R_X86_64_64
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) # ARM discards the .data section because it disallows r/w data in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) # decompressor. So move our .data to .data.efistub and .bss to .bss.efistub,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) # which are preserved explicitly by the decompressor linker script.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) STUBCOPY_FLAGS-$(CONFIG_ARM)	+= --rename-section .data=.data.efistub	\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 				   --rename-section .bss=.bss.efistub,load,alloc
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) STUBCOPY_RELOC-$(CONFIG_ARM)	:= R_ARM_ABS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) # arm64 puts the stub in the kernel proper, which will unnecessarily retain all
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) # code indefinitely unless it is annotated as __init/__initdata/__initconst etc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) # So let's apply the __init annotations at the section level, by prefixing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) # the section names directly. This will ensure that even all the inline string
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) # literals are covered.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) # The fact that the stub and the kernel proper are essentially the same binary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) # also means that we need to be extra careful to make sure that the stub does
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) # not rely on any absolute symbol references, considering that the virtual
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) # kernel mapping that the linker uses is not active yet when the stub is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) # executing. So build all C dependencies of the EFI stub into libstub, and do
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) # a verification pass to see if any absolute relocations exist in any of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) # object files.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) extra-y				:= $(lib-y)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) lib-y				:= $(patsubst %.o,%.stub.o,$(lib-y))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) STUBCOPY_FLAGS-$(CONFIG_ARM64)	+= --prefix-alloc-sections=.init \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 				   --prefix-symbols=__efistub_
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) STUBCOPY_RELOC-$(CONFIG_ARM64)	:= R_AARCH64_ABS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) # For RISC-V, we don't need anything special other than arm64. Keep all the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) # symbols in .init section and make sure that no absolute symbols references
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) # doesn't exist.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) STUBCOPY_FLAGS-$(CONFIG_RISCV)	+= --prefix-alloc-sections=.init \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 				   --prefix-symbols=__efistub_
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) STUBCOPY_RELOC-$(CONFIG_RISCV)	:= R_RISCV_HI20
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) $(obj)/%.stub.o: $(obj)/%.o FORCE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	$(call if_changed,stubcopy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) # Strip debug sections and some other sections that may legally contain
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) # absolute relocations, so that we can inspect the remaining sections for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) # such relocations. If none are found, regenerate the output object, but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) # this time, use objcopy and leave all sections in place.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) #
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) quiet_cmd_stubcopy = STUBCPY $@
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)       cmd_stubcopy =							\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	$(STRIP) --strip-debug -o $@ $<;				\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	if $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y); then		\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 		echo "$@: absolute symbol references not allowed in the EFI stub" >&2; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 		/bin/false;						\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	fi;								\
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	$(OBJCOPY) $(STUBCOPY_FLAGS-y) $< $@