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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
powerpc/boot: Define byteswapping routines for little endian
These are not the most efficient versions of swab but the wrapper does
not do much byte swapping. On a big endian cpu, these routines are
a no-op.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
authored by
Cédric Le Goater
and committed by
Benjamin Herrenschmidt
98fd433a
b636031a
+36
+7
arch/powerpc/boot/of.h
+7
arch/powerpc/boot/of.h
···
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#ifndef _PPC_BOOT_OF_H_
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#define _PPC_BOOT_OF_H_
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#include "swab.h"
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typedef void *phandle;
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typedef u32 ihandle;
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···
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typedef u32 __be32;
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#ifdef __LITTLE_ENDIAN__
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#define cpu_to_be32(x) swab32(x)
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#define be32_to_cpu(x) swab32(x)
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#else
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#define cpu_to_be32(x) (x)
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#define be32_to_cpu(x) (x)
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#endif
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#define PROM_ERROR (-1u)
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+29
arch/powerpc/boot/swab.h
+29
arch/powerpc/boot/swab.h
···
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#ifndef _PPC_BOOT_SWAB_H_
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#define _PPC_BOOT_SWAB_H_
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static inline u16 swab16(u16 x)
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{
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return ((x & (u16)0x00ffU) << 8) |
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((x & (u16)0xff00U) >> 8);
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}
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static inline u32 swab32(u32 x)
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{
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return ((x & (u32)0x000000ffUL) << 24) |
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((x & (u32)0x0000ff00UL) << 8) |
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((x & (u32)0x00ff0000UL) >> 8) |
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((x & (u32)0xff000000UL) >> 24);
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}
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static inline u64 swab64(u64 x)
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{
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return (u64)((x & (u64)0x00000000000000ffULL) << 56) |
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(u64)((x & (u64)0x000000000000ff00ULL) << 40) |
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(u64)((x & (u64)0x0000000000ff0000ULL) << 24) |
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(u64)((x & (u64)0x00000000ff000000ULL) << 8) |
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(u64)((x & (u64)0x000000ff00000000ULL) >> 8) |
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(u64)((x & (u64)0x0000ff0000000000ULL) >> 24) |
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(u64)((x & (u64)0x00ff000000000000ULL) >> 40) |
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(u64)((x & (u64)0xff00000000000000ULL) >> 56);
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}
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#endif /* _PPC_BOOT_SWAB_H_ */