89 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Makefile
		
	
	
	
	
	
			
		
		
	
	
			89 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Makefile
		
	
	
	
	
	
# SPDX-License-Identifier: GPL-2.0-only
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#
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# Makefile for compat_vdso
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#
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# Symbols present in the compat_vdso
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compat_vdso-syms  = rt_sigreturn
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compat_vdso-syms += getcpu
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compat_vdso-syms += flush_icache
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COMPAT_CC := $(CC)
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COMPAT_LD := $(LD)
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# binutils 2.35 does not support the zifencei extension, but in the ISA
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# spec 20191213, G stands for IMAFD_ZICSR_ZIFENCEI.
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ifdef CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
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	COMPAT_CC_FLAGS := -march=rv32g -mabi=ilp32
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else
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	COMPAT_CC_FLAGS := -march=rv32imafd -mabi=ilp32
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endif
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COMPAT_LD_FLAGS := -melf32lriscv
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# Disable attributes, as they're useless and break the build.
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COMPAT_CC_FLAGS += $(call cc-option,-mno-riscv-attribute)
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COMPAT_CC_FLAGS += $(call as-option,-Wa$(comma)-mno-arch-attr)
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# Files to link into the compat_vdso
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obj-compat_vdso = $(patsubst %, %.o, $(compat_vdso-syms)) note.o
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# Build rules
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targets := $(obj-compat_vdso) compat_vdso.so compat_vdso.so.dbg compat_vdso.lds
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obj-compat_vdso := $(addprefix $(obj)/, $(obj-compat_vdso))
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obj-y += compat_vdso.o
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CPPFLAGS_compat_vdso.lds += -P -C -U$(ARCH)
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# Disable profiling and instrumentation for VDSO code
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GCOV_PROFILE := n
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KCOV_INSTRUMENT := n
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KASAN_SANITIZE := n
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UBSAN_SANITIZE := n
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# Force dependency
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$(obj)/compat_vdso.o: $(obj)/compat_vdso.so
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# link rule for the .so file, .lds has to be first
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$(obj)/compat_vdso.so.dbg: $(obj)/compat_vdso.lds $(obj-compat_vdso) FORCE
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	$(call if_changed,compat_vdsold)
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LDFLAGS_compat_vdso.so.dbg = -shared -S -soname=linux-compat_vdso.so.1 \
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	--build-id=sha1 --hash-style=both --eh-frame-hdr
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$(obj-compat_vdso): %.o: %.S FORCE
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	$(call if_changed_dep,compat_vdsoas)
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# strip rule for the .so file
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$(obj)/%.so: OBJCOPYFLAGS := -S
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$(obj)/%.so: $(obj)/%.so.dbg FORCE
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	$(call if_changed,objcopy)
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# Generate VDSO offsets using helper script
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gen-compat_vdsosym := $(srctree)/$(src)/gen_compat_vdso_offsets.sh
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quiet_cmd_compat_vdsosym = VDSOSYM $@
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	cmd_compat_vdsosym = $(NM) $< | $(gen-compat_vdsosym) | LC_ALL=C sort > $@
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include/generated/compat_vdso-offsets.h: $(obj)/compat_vdso.so.dbg FORCE
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	$(call if_changed,compat_vdsosym)
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# actual build commands
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# The DSO images are built using a special linker script
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# Make sure only to export the intended __compat_vdso_xxx symbol offsets.
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quiet_cmd_compat_vdsold = VDSOLD  $@
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      cmd_compat_vdsold = $(COMPAT_LD) $(ld_flags) $(COMPAT_LD_FLAGS) -T $(filter-out FORCE,$^) -o $@.tmp && \
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                   $(OBJCOPY) $(patsubst %, -G __compat_vdso_%, $(compat_vdso-syms)) $@.tmp $@ && \
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                   rm $@.tmp
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# actual build commands
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quiet_cmd_compat_vdsoas = VDSOAS $@
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      cmd_compat_vdsoas = $(COMPAT_CC) $(a_flags) $(COMPAT_CC_FLAGS) -c -o $@ $<
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# install commands for the unstripped file
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quiet_cmd_compat_vdso_install = INSTALL $@
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      cmd_compat_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/compat_vdso/$@
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compat_vdso.so: $(obj)/compat_vdso.so.dbg
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	@mkdir -p $(MODLIB)/compat_vdso
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	$(call cmd,compat_vdso_install)
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compat_vdso_install: compat_vdso.so
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