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powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h

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The next commit will make the way of passing CONFIG options more robust.
Unfortunately, it would uncover another hidden issue; without this
commit, skiroot_defconfig would be broken like this:

|   WRAP    arch/powerpc/boot/zImage.pseries
| arch/powerpc/boot/wrapper.a(decompress.o): In function `bcj_powerpc.isra.10':
| decompress.c:(.text+0x720): undefined reference to `get_unaligned_be32'
| decompress.c:(.text+0x7a8): undefined reference to `put_unaligned_be32'
| make[1]: *** [arch/powerpc/boot/Makefile;383: arch/powerpc/boot/zImage.pseries] Error 1
| make: *** [arch/powerpc/Makefile;295: zImage] Error 2

skiroot_defconfig is the only defconfig that enables CONFIG_KERNEL_XZ
for ppc, which has never been correctly built before.

I figured out the root cause in lib/decompress_unxz.c:

| #ifdef CONFIG_PPC
| #      define XZ_DEC_POWERPC
| #endif

CONFIG_PPC is undefined here in the ppc bootwrapper because autoconf.h
is not included except by arch/powerpc/boot/serial.c

XZ_DEC_POWERPC is not defined, therefore, bcj_powerpc() is not compiled
for the bootwrapper.

With the next commit passing CONFIG_PPC correctly, we would realize that
{get,put}_unaligned_be32 was missing.

Unlike the other decompressors, the ppc bootwrapper duplicates all the
necessary helpers in arch/powerpc/boot/.

The other architectures define __KERNEL__ and pull in helpers for
building the decompressors.

If ppc bootwrapper had defined __KERNEL__, lib/xz/xz_private.h would
have included <asm/unaligned.h>:

| #ifdef __KERNEL__
| #       include <linux/xz.h>
| #       include <linux/kernel.h>
| #       include <asm/unaligned.h>

However, doing so would cause tons of definition conflicts since the
bootwrapper has duplicated everything.

I just added copies of {get,put}_unaligned_be32, following the
bootwrapper coding convention.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190705100144.28785-1-yamada.masahiro@socionext.com
This commit is contained in:
Masahiro Yamada 2019-07-05 19:01:43 +09:00 committed by Michael Ellerman
parent 0fc12c022a
commit 9e005b761e
1 changed files with 20 additions and 0 deletions
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20
arch/powerpc/boot/xz_config.h
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@ -20,10 +20,30 @@ static inline uint32_t swab32p(void *p)
#ifdef __LITTLE_ENDIAN__
#define get_le32(p) (*((uint32_t *) (p)))
#define cpu_to_be32(x) swab32(x)
static inline u32 be32_to_cpup(const u32 *p)
{
return swab32p((u32 *)p);
}
#else
#define get_le32(p) swab32p(p)
#define cpu_to_be32(x) (x)
static inline u32 be32_to_cpup(const u32 *p)
{
return *p;
}
#endif
static inline uint32_t get_unaligned_be32(const void *p)
{
return be32_to_cpup(p);
}
static inline void put_unaligned_be32(u32 val, void *p)
{
*((u32 *)p) = cpu_to_be32(val);
}
#define memeq(a, b, size) (memcmp(a, b, size) == 0)
#define memzero(buf, size) memset(buf, 0, size)