@@ -6,12 +6,3 @@ hyp-stub.S
piggy_data
vmlinux
vmlinux.lds
-
-# borrowed libfdt files
-fdt.c
-fdt.h
-fdt_ro.c
-fdt_rw.c
-fdt_wip.c
-libfdt.h
-libfdt_internal.h
@@ -76,29 +76,31 @@ compress-$(CONFIG_KERNEL_LZMA) = lzma
compress-$(CONFIG_KERNEL_XZ) = xzkern
compress-$(CONFIG_KERNEL_LZ4) = lz4
-# Borrowed libfdt files for the ATAG compatibility mode
-
-libfdt := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c
-libfdt_hdrs := fdt.h libfdt.h libfdt_internal.h
-
-libfdt_objs := $(addsuffix .o, $(basename $(libfdt)))
+ifeq ($(CONFIG_ARM_ATAG_DTB_COMPAT),y)
+libfdt_objs = fdt_rw.o fdt_ro.o fdt_wip.o fdt.o atags_to_fdt.o
-$(addprefix $(obj)/,$(libfdt) $(libfdt_hdrs)): $(obj)/%: $(srctree)/scripts/dtc/libfdt/%
- $(call cmd,shipped)
+OBJS += $(libfdt_objs)
-$(addprefix $(obj)/,$(libfdt_objs) atags_to_fdt.o): \
- $(addprefix $(obj)/,$(libfdt_hdrs))
+# -fstack-protector-strong triggers protection checks in this code,
+# but it is being used too early to link to meaningful stack_chk logic.
+nossp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
+$(foreach o, $(libfdt_objs), \
+ $(eval CFLAGS_$(o) := -I $(srctree)/scripts/dtc/libfdt $(nossp-flags-y)))
+
+# These were previously generated C files. When you are building the kernel
+# with O=, make sure to remove the stale files in the output tree. Otherwise,
+# the build system wrongly compiles the stale ones.
+ifdef building_out_of_srctree
+$(shell rm -f $(addprefix $(obj)/, fdt_rw.c fdt_ro.c fdt_wip.c fdt.c))
+endif
-ifeq ($(CONFIG_ARM_ATAG_DTB_COMPAT),y)
-OBJS += $(libfdt_objs) atags_to_fdt.o
endif
targets := vmlinux vmlinux.lds piggy_data piggy.o \
lib1funcs.o ashldi3.o bswapsdi2.o \
head.o $(OBJS)
-clean-files += piggy_data lib1funcs.S ashldi3.S bswapsdi2.S \
- $(libfdt) $(libfdt_hdrs) hyp-stub.S
+clean-files += piggy_data lib1funcs.S ashldi3.S bswapsdi2.S hyp-stub.S
KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
KBUILD_CFLAGS += $(DISABLE_ARM_SSP_PER_TASK_PLUGIN)
@@ -108,15 +110,6 @@ ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
endif
-# -fstack-protector-strong triggers protection checks in this code,
-# but it is being used too early to link to meaningful stack_chk logic.
-nossp-flags-$(CONFIG_CC_HAS_STACKPROTECTOR_NONE) := -fno-stack-protector
-CFLAGS_atags_to_fdt.o := $(nossp-flags-y)
-CFLAGS_fdt.o := $(nossp-flags-y)
-CFLAGS_fdt_ro.o := $(nossp-flags-y)
-CFLAGS_fdt_rw.o := $(nossp-flags-y)
-CFLAGS_fdt_wip.o := $(nossp-flags-y)
-
ccflags-y := -fpic $(call cc-option,-mno-single-pic-base,) -fno-builtin -I$(obj)
asflags-y := -DZIMAGE
@@ -1,4 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
+#include <linux/libfdt_env.h>
#include <asm/setup.h>
#include <libfdt.h>
new file mode 100644
@@ -0,0 +1 @@
+#include "../../../../lib/fdt.c"
new file mode 100644
@@ -0,0 +1 @@
+#include "../../../../lib/fdt_ro.c"
new file mode 100644
@@ -0,0 +1 @@
+#include "../../../../lib/fdt_rw.c"
new file mode 100644
@@ -0,0 +1 @@
+#include "../../../../lib/fdt_wip.c"
deleted file mode 100644
@@ -1,24 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ARM_LIBFDT_ENV_H
-#define _ARM_LIBFDT_ENV_H
-
-#include <linux/limits.h>
-#include <linux/types.h>
-#include <linux/string.h>
-#include <asm/byteorder.h>
-
-#define INT32_MAX S32_MAX
-#define UINT32_MAX U32_MAX
-
-typedef __be16 fdt16_t;
-typedef __be32 fdt32_t;
-typedef __be64 fdt64_t;
-
-#define fdt16_to_cpu(x) be16_to_cpu(x)
-#define cpu_to_fdt16(x) cpu_to_be16(x)
-#define fdt32_to_cpu(x) be32_to_cpu(x)
-#define cpu_to_fdt32(x) cpu_to_be32(x)
-#define fdt64_to_cpu(x) be64_to_cpu(x)
-#define cpu_to_fdt64(x) cpu_to_be64(x)
-
-#endif
Copying source files during the build time may not end up with as clean code as expected. lib/fdt*.c simply wrap scripts/dtc/libfdt/fdt*.c, and it works nicely. Let's follow that approach for the arm decompressor, too. Add four wrappers, arch/arm/boot/compressed/fdt*.c and remove the Makefile messes. Another nice thing is we no longer need to maintain the own libfdt_env.h because the decompressor can include <linux/libfdt_env.h>. There is a subtle problem when generated files are turned into check-in files. When you are doing a rebuild of an existing object tree with O= option, there exists stale "shipped" copies that the old Makefile implementation created. The build system ends up with compiling the stale generated files because Make searches for prerequisites in the current directory, i.e. $(objtree) first, and then the directory listed in VPATH, i.e. $(srctree). To mend this issue, I added the following code: ifdef building_out_of_srctree $(shell rm -f $(addprefix $(obj)/, fdt_rw.c fdt_ro.c fdt_wip.c fdt.c)) endif This will need to stay for a while because "git bisect" crossing this commit, otherwise, would result in a build error. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- KernelVersion: v5.5-rc1 Changes in v3: - remove stale generated Changes in v2: - fix build error arch/arm/boot/compressed/.gitignore | 9 ------ arch/arm/boot/compressed/Makefile | 39 ++++++++++--------------- arch/arm/boot/compressed/atags_to_fdt.c | 1 + arch/arm/boot/compressed/fdt.c | 1 + arch/arm/boot/compressed/fdt_ro.c | 1 + arch/arm/boot/compressed/fdt_rw.c | 1 + arch/arm/boot/compressed/fdt_wip.c | 1 + arch/arm/boot/compressed/libfdt_env.h | 24 --------------- 8 files changed, 21 insertions(+), 56 deletions(-) create mode 100644 arch/arm/boot/compressed/fdt.c create mode 100644 arch/arm/boot/compressed/fdt_ro.c create mode 100644 arch/arm/boot/compressed/fdt_rw.c create mode 100644 arch/arm/boot/compressed/fdt_wip.c delete mode 100644 arch/arm/boot/compressed/libfdt_env.h