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sh: wire up arch overrides for unaligned access on the SH4a

PATCH In review Harvey Harrison 2 participants 3 messages Nov 30, 2008 – Dec 1, 2008

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PATCH 4/7 sh: wire up arch overrides for unaligned access on the SH4a

---
 arch/sh/include/asm/unaligned-sh4a.h |  258 ----------------------------------
 arch/sh/include/asm/unaligned.h      |   76 ++++++++--
 2 files changed, 61 insertions(+), 273 deletions(-)
arch/sh/include/asm/unaligned-sh4a.h deleted +0 -258
deleted file mode 100644
index d8f8977..0000000
@@ -1,258 +0,0 @@
-#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 16 and 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 gauranteed 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/types.h>
-#include <asm/byteorder.h>
-
-static __always_inline u32 __get_unaligned_cpu32(const u8 *p)
-{
-	unsigned long unaligned;
-
-	__asm__ __volatile__ (
-		"movua.l	@%1, %0\n\t"
-		 : "=z" (unaligned)
-		 : "r" (p)
-	);
-
-	return unaligned;
-}
-
-struct __una_u16 { u16 x __attribute__((packed)); };
-struct __una_u32 { u32 x __attribute__((packed)); };
-struct __una_u64 { u64 x __attribute__((packed)); };
-
-static inline u16 __get_unaligned_cpu16(const u8 *p)
-{
-#ifdef __LITTLE_ENDIAN
-	return __get_unaligned_cpu32(p) & 0xffff;
-#else
-	return __get_unaligned_cpu32(p) >> 16;
-#endif
-}
-
-/*
- * 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 __get_unaligned_cpu64(const u8 *p)
-{
-#ifdef __LITTLE_ENDIAN
-	return (u64)__get_unaligned_cpu32(p + 4) << 32 |
-		    __get_unaligned_cpu32(p);
-#else
-	return (u64)__get_unaligned_cpu32(p) << 32 |
-		    __get_unaligned_cpu32(p + 4);
-#endif
-}
-
-static inline u16 get_unaligned_le16(const void *p)
-{
-	return le16_to_cpu(__get_unaligned_cpu16(p));
-}
-
-static inline u32 get_unaligned_le32(const void *p)
-{
-	return le32_to_cpu(__get_unaligned_cpu32(p));
-}
-
-static inline u64 get_unaligned_le64(const void *p)
-{
-	return le64_to_cpu(__get_unaligned_cpu64(p));
-}
-
-static inline u16 get_unaligned_be16(const void *p)
-{
-	return be16_to_cpu(__get_unaligned_cpu16(p));
-}
-
-static inline u32 get_unaligned_be32(const void *p)
-{
-	return be32_to_cpu(__get_unaligned_cpu32(p));
-}
-
-static inline u64 get_unaligned_be64(const void *p)
-{
-	return be64_to_cpu(__get_unaligned_cpu64(p));
-}
-
-static inline void __put_le16_noalign(u8 *p, u16 val)
-{
-	*p++ = val;
-	*p++ = val >> 8;
-}
-
-static inline void __put_le32_noalign(u8 *p, u32 val)
-{
-	__put_le16_noalign(p, val);
-	__put_le16_noalign(p + 2, val >> 16);
-}
-
-static inline void __put_le64_noalign(u8 *p, u64 val)
-{
-	__put_le32_noalign(p, val);
-	__put_le32_noalign(p + 4, val >> 32);
-}
-
-static inline void __put_be16_noalign(u8 *p, u16 val)
-{
-	*p++ = val >> 8;
-	*p++ = val;
-}
-
-static inline void __put_be32_noalign(u8 *p, u32 val)
-{
-	__put_be16_noalign(p, val >> 16);
-	__put_be16_noalign(p + 2, val);
-}
-
-static inline void __put_be64_noalign(u8 *p, u64 val)
-{
-	__put_be32_noalign(p, val >> 32);
-	__put_be32_noalign(p + 4, val);
-}
-
-static inline void put_unaligned_le16(u16 val, void *p)
-{
-#ifdef __LITTLE_ENDIAN
-	((struct __una_u16 *)p)->x = val;
-#else
-	__put_le16_noalign(p, val);
-#endif
-}
-
-static inline void put_unaligned_le32(u32 val, void *p)
-{
-#ifdef __LITTLE_ENDIAN
-	((struct __una_u32 *)p)->x = val;
-#else
-	__put_le32_noalign(p, val);
-#endif
-}
-
-static inline void put_unaligned_le64(u64 val, void *p)
-{
-#ifdef __LITTLE_ENDIAN
-	((struct __una_u64 *)p)->x = val;
-#else
-	__put_le64_noalign(p, val);
-#endif
-}
-
-static inline void put_unaligned_be16(u16 val, void *p)
-{
-#ifdef __BIG_ENDIAN
-	((struct __una_u16 *)p)->x = val;
-#else
-	__put_be16_noalign(p, val);
-#endif
-}
-
-static inline void put_unaligned_be32(u32 val, void *p)
-{
-#ifdef __BIG_ENDIAN
-	((struct __una_u32 *)p)->x = val;
-#else
-	__put_be32_noalign(p, val);
-#endif
-}
-
-static inline void put_unaligned_be64(u64 val, void *p)
-{
-#ifdef __BIG_ENDIAN
-	((struct __una_u64 *)p)->x = val;
-#else
-	__put_be64_noalign(p, val);
-#endif
-}
-
-/*
- * Cause a link-time error if we try an unaligned access other than
- * 1,2,4 or 8 bytes long
- */
-extern void __bad_unaligned_access_size(void);
-
-#define __get_unaligned_le(ptr) ((__force typeof(*(ptr)))({			\
-	__builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr),			\
-	__builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_le16((ptr)),	\
-	__builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_le32((ptr)),	\
-	__builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_le64((ptr)),	\
-	__bad_unaligned_access_size()))));					\
-	}))
-
-#define __get_unaligned_be(ptr) ((__force typeof(*(ptr)))({			\
-	__builtin_choose_expr(sizeof(*(ptr)) == 1, *(ptr),			\
-	__builtin_choose_expr(sizeof(*(ptr)) == 2, get_unaligned_be16((ptr)),	\
-	__builtin_choose_expr(sizeof(*(ptr)) == 4, get_unaligned_be32((ptr)),	\
-	__builtin_choose_expr(sizeof(*(ptr)) == 8, get_unaligned_be64((ptr)),	\
-	__bad_unaligned_access_size()))));					\
-	}))
-
-#define __put_unaligned_le(val, ptr) ({					\
-	void *__gu_p = (ptr);						\
-	switch (sizeof(*(ptr))) {					\
-	case 1:								\
-		*(u8 *)__gu_p = (__force u8)(val);			\
-		break;							\
-	case 2:								\
-		put_unaligned_le16((__force u16)(val), __gu_p);		\
-		break;							\
-	case 4:								\
-		put_unaligned_le32((__force u32)(val), __gu_p);		\
-		break;							\
-	case 8:								\
-		put_unaligned_le64((__force u64)(val), __gu_p);		\
-		break;							\
-	default:							\
-		__bad_unaligned_access_size();				\
-		break;							\
-	}								\
-	(void)0; })
-
-#define __put_unaligned_be(val, ptr) ({					\
-	void *__gu_p = (ptr);						\
-	switch (sizeof(*(ptr))) {					\
-	case 1:								\
-		*(u8 *)__gu_p = (__force u8)(val);			\
-		break;							\
-	case 2:								\
-		put_unaligned_be16((__force u16)(val), __gu_p);		\
-		break;							\
-	case 4:								\
-		put_unaligned_be32((__force u32)(val), __gu_p);		\
-		break;							\
-	case 8:								\
-		put_unaligned_be64((__force u64)(val), __gu_p);		\
-		break;							\
-	default:							\
-		__bad_unaligned_access_size();				\
-		break;							\
-	}								\
-	(void)0; })
-
-#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 */
arch/sh/include/asm/unaligned.h +61 -15

85 lines not on this page · raw message

Signature · 1 line
1.6.0.4.1044.g77718
#2 lore raw
Quoted 10 lines · Paul Mundt
Quoted 6 lines · Harvey Harrison
---
 arch/sh/include/asm/unaligned-sh4a.h |  258 ----------------------------------
 arch/sh/include/asm/unaligned.h      |   76 ++++++++--
 2 files changed, 61 insertions(+), 273 deletions(-)

Thanks for looking at this!

No worries, I've also CC'd the AVR32 maintainer as I think his arch could do something similar as that arch also provides limited unaligned access that might be worth adding an override for.

Cheers,

Harvey