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Elixir Cross Referencer

GEN_ISR_TABLE := $(srctree)/arch/common/gen_isr_tables.py
OUTPUT_SRC := isr_tables.c
OUTPUT_OBJ := isr_tables.o

ifeq ($(ARCH),riscv32)
OUTPUT_FORMAT := elf32-littleriscv
else
OUTPUT_FORMAT := elf32-little$(ARCH)
endif

GEN_ISR_TABLE_EXTRA_ARGS :=

ifeq ($(KBUILD_VERBOSE),1)
GEN_ISR_TABLE_EXTRA_ARGS += --debug
endif

ifeq ($(CONFIG_GEN_SW_ISR_TABLE),y)
GEN_ISR_TABLE_EXTRA_ARGS += --sw-isr-table
endif

ifeq ($(CONFIG_GEN_IRQ_VECTOR_TABLE),y)
GEN_ISR_TABLE_EXTRA_ARGS += --vector-table
endif

# Rule to extract the .intList section from the $(PREBUILT_KERNEL) binary
# and create the source file $(OUTPUT_SRC). This is a C file which contains
# the interrupt tables.
quiet_cmd_gen_irq = IRQ     $@
      cmd_gen_irq = \
( \
	$(OBJCOPY) -I $(OUTPUT_FORMAT) -O binary --only-section=.intList \
		$< isrList.bin && \
	$(GEN_ISR_TABLE) --output-source $@ \
		--intlist isrList.bin $(GEN_ISR_TABLE_EXTRA_ARGS) \
)

$(OUTPUT_SRC): $(PREBUILT_KERNEL) $(GEN_ISR_TABLE)
	$(call cmd,gen_irq)

# Build system pattern rules will handle building $(OUTPUT_OBJ) from
# $(OUTPUT_SRC), nothing we need to do here explicitly for its compilation.

# Now link the kernel again, this time with the compiled interrupt tables
# included, replacing the dummy tables defined in arch/common/isr_tables.c
#
# On x86, we just strip out the intList with objcopy -j. However this is not
# very portable; for instance on ARM this results in a zero-sized program
# header segment which produces a linker warning and gives QEMU fits.
# Set to NOLOAD instead, now that we have extracted the information we need
# from it.
quiet_cmd_lnk_elf = LINK    $@
      cmd_lnk_elf = \
( \
	$(CC) -T linker.cmd $(OUTPUT_OBJ) @$(KERNEL_NAME).lnk \
		-o elf.tmp && \
	$(OBJCOPY) -I $(OUTPUT_FORMAT) -O $(OUTPUT_FORMAT) \
		--set-section-flags .intList=noload \
		elf.tmp $@ && \
	rm -f elf.tmp; \
)

$(KERNEL_ELF_NAME): $(OUTPUT_OBJ) linker.cmd
	$(call cmd,lnk_elf)
	@$(srctree)/scripts/check_link_map.py $(KERNEL_NAME).map
	@$(WARN_ABOUT_ASSERT)
	@$(WARN_ABOUT_DEPRECATION)