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#ifndef __ASM_SH_UNALIGNED_SH4A_H
#define __ASM_SH_UNALIGNED_SH4A_H
/*
* SH-4A has support for unaligned 32-bit loads, and 32-bit loads only.
* Support for 64-bit accesses are done through shifting and masking
* relative to the endianness. Unaligned stores are not supported by the
* instruction encoding, so these continue to use the packed
* struct.
*
* The same note as with the movli.l/movco.l pair applies here, as long
* as the load is guaranteed to be inlined, nothing else will hook in to
* r0 and we get the return value for free.
*
* NOTE: Due to the fact we require r0 encoding, care should be taken to
* avoid mixing these heavily with other r0 consumers, such as the atomic
* ops. Failure to adhere to this can result in the compiler running out
* of spill registers and blowing up when building at low optimization
* levels. See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34777.
*/
#include <linux/unaligned/packed_struct.h>
#include <linux/types.h>
#include <asm/byteorder.h>
static inline u16 sh4a_get_unaligned_cpu16(const u8 *p)
{
#ifdef __LITTLE_ENDIAN
return p[0] | p[1] << 8;
#else
return p[0] << 8 | p[1];
#endif
}
static __always_inline u32 sh4a_get_unaligned_cpu32(const u8 *p)
{
unsigned long unaligned;
__asm__ __volatile__ (
"movua.l @%1, %0\n\t"
: "=z" (unaligned)
: "r" (p)
);
return unaligned;
}
/*
* Even though movua.l supports auto-increment on the read side, it can
* only store to r0 due to instruction encoding constraints, so just let
* the compiler sort it out on its own.
*/
static inline u64 sh4a_get_unaligned_cpu64(const u8 *p)
{
#ifdef __LITTLE_ENDIAN
return (u64)sh4a_get_unaligned_cpu32(p + 4) << 32 |
sh4a_get_unaligned_cpu32(p);
#else
return (u64)sh4a_get_unaligned_cpu32(p) << 32 |
sh4a_get_unaligned_cpu32(p + 4);
#endif
}
static inline u16 get_unaligned_le16(const void *p)
{
return le16_to_cpu(sh4a_get_unaligned_cpu16(p));
}
static inline u32 get_unaligned_le32(const void *p)
{
return le32_to_cpu(sh4a_get_unaligned_cpu32(p));
}
static inline u64 get_unaligned_le64(const void *p)
{
return le64_to_cpu(sh4a_get_unaligned_cpu64(p));
}
static inline u16 get_unaligned_be16(const void *p)
{
return be16_to_cpu(sh4a_get_unaligned_cpu16(p));
}
static inline u32 get_unaligned_be32(const void *p)
{
return be32_to_cpu(sh4a_get_unaligned_cpu32(p));
}
static inline u64 get_unaligned_be64(const void *p)
{
return be64_to_cpu(sh4a_get_unaligned_cpu64(p));
}
static inline void nonnative_put_le16(u16 val, u8 *p)
{
*p++ = val;
*p++ = val >> 8;
}
static inline void nonnative_put_le32(u32 val, u8 *p)
{
nonnative_put_le16(val, p);
nonnative_put_le16(val >> 16, p + 2);
}
static inline void nonnative_put_le64(u64 val, u8 *p)
{
nonnative_put_le32(val, p);
nonnative_put_le32(val >> 32, p + 4);
}
static inline void nonnative_put_be16(u16 val, u8 *p)
{
*p++ = val >> 8;
*p++ = val;
}
static inline void nonnative_put_be32(u32 val, u8 *p)
{
nonnative_put_be16(val >> 16, p);
nonnative_put_be16(val, p + 2);
}
static inline void nonnative_put_be64(u64 val, u8 *p)
{
nonnative_put_be32(val >> 32, p);
nonnative_put_be32(val, p + 4);
}
static inline void put_unaligned_le16(u16 val, void *p)
{
#ifdef __LITTLE_ENDIAN
__put_unaligned_cpu16(val, p);
#else
nonnative_put_le16(val, p);
#endif
}
static inline void put_unaligned_le32(u32 val, void *p)
{
#ifdef __LITTLE_ENDIAN
__put_unaligned_cpu32(val, p);
#else
nonnative_put_le32(val, p);
#endif
}
static inline void put_unaligned_le64(u64 val, void *p)
{
#ifdef __LITTLE_ENDIAN
__put_unaligned_cpu64(val, p);
#else
nonnative_put_le64(val, p);
#endif
}
static inline void put_unaligned_be16(u16 val, void *p)
{
#ifdef __BIG_ENDIAN
__put_unaligned_cpu16(val, p);
#else
nonnative_put_be16(val, p);
#endif
}
static inline void put_unaligned_be32(u32 val, void *p)
{
#ifdef __BIG_ENDIAN
__put_unaligned_cpu32(val, p);
#else
nonnative_put_be32(val, p);
#endif
}
static inline void put_unaligned_be64(u64 val, void *p)
{
#ifdef __BIG_ENDIAN
__put_unaligned_cpu64(val, p);
#else
nonnative_put_be64(val, p);
#endif
}
/*
* While it's a bit non-obvious, even though the generic le/be wrappers
* use the __get/put_xxx prefixing, they actually wrap in to the
* non-prefixed get/put_xxx variants as provided above.
*/
#include <linux/unaligned/generic.h>
#ifdef __LITTLE_ENDIAN
# define get_unaligned __get_unaligned_le
# define put_unaligned __put_unaligned_le
#else
# define get_unaligned __get_unaligned_be
# define put_unaligned __put_unaligned_be
#endif
#endif /* __ASM_SH_UNALIGNED_SH4A_H */
