[PATCH v2] powerpc/boot: pass CONFIG options in a simpler and more robust way

Commit 5e9dcb6188a4 ("powerpc/boot: Expose Kconfig symbols to wrapper")
was wrong, but commit e41b93a6be57 ("powerpc/boot: Fix build failures
with -j 1") was also wrong.

The correct dependency is:

  $(obj)/serial.o: $(obj)/autoconf.h

However, I do not see the reason why we need to copy autoconf.h to
arch/power/boot/. Nor do I see consistency in the way of passing
CONFIG options.

decompress.c references CONFIG_KERNEL_GZIP and CONFIG_KERNEL_XZ, which
are passed via the command line.

serial.c includes autoconf.h to reference a couple of CONFIG options,
but this is fragile because we often forget to include "autoconf.h"
from source files.

In fact, it is already broken.

ppc_asm.h references CONFIG_PPC_8xx, but utils.S is not given any way
to access CONFIG options. So, CONFIG_PPC_8xx is never defined here.

Pass $(LINUXINCLUDE) to make sure CONFIG options are accessible from
all .c and .S files in arch/powerpc/boot/.

I also removed the -traditional flag to make include/linux/kconfig.h
work. This flag makes the preprocessor imitate the behavior of the
pre-standard C compiler, but I do not understand why it is necessary.

Signed-off-by: Masahiro Yamada <redacted>
---

Changes in v2:
 - reword commit log

 arch/powerpc/boot/.gitignore |  2 --
 arch/powerpc/boot/Makefile   | 14 +++-----------
 arch/powerpc/boot/serial.c   |  1 -
 3 files changed, 3 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/boot/.gitignore b/arch/powerpc/boot/.gitignore
index 32034a0c..6610665 100644
--- a/arch/powerpc/boot/.gitignore
+++ b/arch/powerpc/boot/.gitignore

@@ -44,5 +44,3 @@ fdt_sw.c
 fdt_wip.c
 libfdt.h
 libfdt_internal.h
-autoconf.h
-

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index 73d1f35..b8a82be 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile

@@ -20,9 +20,6 @@
 
 all: $(obj)/zImage
 
-compress-$(CONFIG_KERNEL_GZIP) := CONFIG_KERNEL_GZIP
-compress-$(CONFIG_KERNEL_XZ)   := CONFIG_KERNEL_XZ
-
 ifdef CROSS32_COMPILE
     BOOTCC := $(CROSS32_COMPILE)gcc
     BOOTAR := $(CROSS32_COMPILE)ar

@@ -34,7 +31,7 @@ endif
 BOOTCFLAGS    := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
 		 -fno-strict-aliasing -O2 -msoft-float -mno-altivec -mno-vsx \
 		 -pipe -fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
-		 -D$(compress-y)
+		 $(LINUXINCLUDE)
 
 ifdef CONFIG_PPC64_BOOT_WRAPPER
 BOOTCFLAGS	+= -m64

@@ -51,7 +48,7 @@ BOOTCFLAGS	+= -mlittle-endian
 BOOTCFLAGS	+= $(call cc-option,-mabi=elfv2)
 endif
 
-BOOTAFLAGS	:= -D__ASSEMBLY__ $(BOOTCFLAGS) -traditional -nostdinc
+BOOTAFLAGS	:= -D__ASSEMBLY__ $(BOOTCFLAGS) -nostdinc
 
 BOOTARFLAGS	:= -cr$(KBUILD_ARFLAGS)
 

@@ -202,14 +199,9 @@ $(obj)/empty.c:
 $(obj)/zImage.coff.lds $(obj)/zImage.ps3.lds : $(obj)/%: $(srctree)/$(src)/%.S
 	$(Q)cp $< $@
 
-$(srctree)/$(src)/serial.c: $(obj)/autoconf.h
-
-$(obj)/autoconf.h: $(obj)/%: $(objtree)/include/generated/%
-	$(Q)cp $< $@
-
 clean-files := $(zlib-) $(zlibheader-) $(zliblinuxheader-) \
 		$(zlib-decomp-) $(libfdt) $(libfdtheader) \
-		autoconf.h empty.c zImage.coff.lds zImage.ps3.lds zImage.lds
+		empty.c zImage.coff.lds zImage.ps3.lds zImage.lds
 
 quiet_cmd_bootcc = BOOTCC  $@
       cmd_bootcc = $(BOOTCC) -Wp,-MD,$(depfile) $(BOOTCFLAGS) -c -o $@ $<

diff --git a/arch/powerpc/boot/serial.c b/arch/powerpc/boot/serial.c
index b0491b8..9457863 100644
--- a/arch/powerpc/boot/serial.c
+++ b/arch/powerpc/boot/serial.c

@@ -18,7 +18,6 @@
 #include "stdio.h"
 #include "io.h"
 #include "ops.h"
-#include "autoconf.h"
 
 static int serial_open(void)
 {

-- 
2.7.4

On Mon, May 13, 2019 at 11:24 PM Masahiro Yamada
[off-list ref] wrote:

Commit 5e9dcb6188a4 ("powerpc/boot: Expose Kconfig symbols to wrapper")
was wrong, but commit e41b93a6be57 ("powerpc/boot: Fix build failures
with -j 1") was also wrong.

The correct dependency is:

  $(obj)/serial.o: $(obj)/autoconf.h

However, I do not see the reason why we need to copy autoconf.h to
arch/power/boot/. Nor do I see consistency in the way of passing
CONFIG options.

decompress.c references CONFIG_KERNEL_GZIP and CONFIG_KERNEL_XZ, which
are passed via the command line.

serial.c includes autoconf.h to reference a couple of CONFIG options,
but this is fragile because we often forget to include "autoconf.h"
from source files.

In fact, it is already broken.

ppc_asm.h references CONFIG_PPC_8xx, but utils.S is not given any way
to access CONFIG options. So, CONFIG_PPC_8xx is never defined here.

Pass $(LINUXINCLUDE) to make sure CONFIG options are accessible from
all .c and .S files in arch/powerpc/boot/.

I also removed the -traditional flag to make include/linux/kconfig.h
work. This flag makes the preprocessor imitate the behavior of the
pre-standard C compiler, but I do not understand why it is necessary.

Signed-off-by: Masahiro Yamada <redacted>
---

Ping.

-- 
Best Regards
Masahiro Yamada

Masahiro Yamada [off-list ref] writes:

Commit 5e9dcb6188a4 ("powerpc/boot: Expose Kconfig symbols to wrapper")
was wrong, but commit e41b93a6be57 ("powerpc/boot: Fix build failures
with -j 1") was also wrong.

The correct dependency is:

  $(obj)/serial.o: $(obj)/autoconf.h

However, I do not see the reason why we need to copy autoconf.h to
arch/power/boot/. Nor do I see consistency in the way of passing
CONFIG options.

decompress.c references CONFIG_KERNEL_GZIP and CONFIG_KERNEL_XZ, which
are passed via the command line.

serial.c includes autoconf.h to reference a couple of CONFIG options,
but this is fragile because we often forget to include "autoconf.h"
from source files.

In fact, it is already broken.

ppc_asm.h references CONFIG_PPC_8xx, but utils.S is not given any way
to access CONFIG options. So, CONFIG_PPC_8xx is never defined here.

Pass $(LINUXINCLUDE) to make sure CONFIG options are accessible from
all .c and .S files in arch/powerpc/boot/.

This breaks our skiroot_defconfig, I don't know why yet:

  In file included from /kisskb/src/arch/powerpc/boot/../../../lib/decompress_unxz.c:236:0,
                   from /kisskb/src/arch/powerpc/boot/decompress.c:42:
  /kisskb/src/arch/powerpc/boot/../../../lib/xz/xz_dec_bcj.c: In function 'bcj_powerpc':
  /kisskb/src/arch/powerpc/boot/../../../lib/xz/xz_dec_bcj.c:166:11: warning: implicit declaration of function 'get_unaligned_be32' [-Wimplicit-function-declaration]
     instr = get_unaligned_be32(buf + i);


http://kisskb.ellerman.id.au/kisskb/buildresult/13862914/

cheers

On Thu, Jul 4, 2019 at 9:26 AM Michael Ellerman [off-list ref] wrote:

Masahiro Yamada [off-list ref] writes:

quoted

Commit 5e9dcb6188a4 ("powerpc/boot: Expose Kconfig symbols to wrapper")
was wrong, but commit e41b93a6be57 ("powerpc/boot: Fix build failures
with -j 1") was also wrong.

The correct dependency is:

  $(obj)/serial.o: $(obj)/autoconf.h

However, I do not see the reason why we need to copy autoconf.h to
arch/power/boot/. Nor do I see consistency in the way of passing
CONFIG options.

decompress.c references CONFIG_KERNEL_GZIP and CONFIG_KERNEL_XZ, which
are passed via the command line.

serial.c includes autoconf.h to reference a couple of CONFIG options,
but this is fragile because we often forget to include "autoconf.h"
from source files.

In fact, it is already broken.

ppc_asm.h references CONFIG_PPC_8xx, but utils.S is not given any way
to access CONFIG options. So, CONFIG_PPC_8xx is never defined here.

Pass $(LINUXINCLUDE) to make sure CONFIG options are accessible from
all .c and .S files in arch/powerpc/boot/.

This breaks our skiroot_defconfig, I don't know why yet:

  In file included from /kisskb/src/arch/powerpc/boot/../../../lib/decompress_unxz.c:236:0,
                   from /kisskb/src/arch/powerpc/boot/decompress.c:42:
  /kisskb/src/arch/powerpc/boot/../../../lib/xz/xz_dec_bcj.c: In function 'bcj_powerpc':
  /kisskb/src/arch/powerpc/boot/../../../lib/xz/xz_dec_bcj.c:166:11: warning: implicit declaration of function 'get_unaligned_be32' [-Wimplicit-function-declaration]
     instr = get_unaligned_be32(buf + i);

OK, now I see the cause of the error.

I will insert a new patch in v3.

Thanks.

http://kisskb.ellerman.id.au/kisskb/buildresult/13862914/

cheers

-- 
Best Regards
Masahiro Yamada