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| author | David Brownell <david-b@pacbell.net> | 2007-05-25 18:47:47 -0700 |
|---|---|---|
| committer | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2007-07-18 20:45:50 +0200 |
| commit | c6083cd61b5a64a1c73d1634744382f54cb99595 (patch) | |
| tree | 4ad4409a074a9de87a03bc2162d27e326f2c0498 /include/asm-avr32 | |
| parent | 8b4a40809e5330c9da5d20107d693d92d73b31dc (diff) | |
| download | lwn-c6083cd61b5a64a1c73d1634744382f54cb99595.tar.gz lwn-c6083cd61b5a64a1c73d1634744382f54cb99595.zip | |
[AVR32] faster avr32 unaligned access
Use a more conventional implementation for unaligned access, and include
an AT32AP-specific optimization: the CPU will handle unaligned words.
The result is always faster and smaller for 8, 16, and 32 bit values.
For 64 bit quantities, it's presumably larger.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Diffstat (limited to 'include/asm-avr32')
| -rw-r--r-- | include/asm-avr32/unaligned.h | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/include/asm-avr32/unaligned.h b/include/asm-avr32/unaligned.h index 3042723fcbfd..791361786fcc 100644 --- a/include/asm-avr32/unaligned.h +++ b/include/asm-avr32/unaligned.h @@ -6,20 +6,31 @@ * implementation. The AVR32 AP implementation can handle unaligned * words, but halfwords must be halfword-aligned, and doublewords must * be word-aligned. - * - * TODO: Make all this CPU-specific and optimize. */ -#include <linux/string.h> +#include <asm-generic/unaligned.h> -/* Use memmove here, so gcc does not insert a __builtin_memcpy. */ +#ifdef CONFIG_CPU_AT32AP7000 +/* REVISIT calling memmove() may be smaller for 64-bit values ... */ + +#undef get_unaligned #define get_unaligned(ptr) \ - ({ __typeof__(*(ptr)) __tmp; memmove(&__tmp, (ptr), sizeof(*(ptr))); __tmp; }) + ___get_unaligned(ptr, sizeof((*ptr))) +#define ___get_unaligned(ptr, size) \ + ((size == 4) ? *(ptr) : __get_unaligned(ptr, size)) + +#undef put_unaligned +#define put_unaligned(val, ptr) \ + ___put_unaligned((__u64)(val), ptr, sizeof((*ptr))) +#define ___put_unaligned(val, ptr, size) \ +do { \ + if (size == 4) \ + *(ptr) = (val); \ + else \ + __put_unaligned(val, ptr, size); \ +} while (0) -#define put_unaligned(val, ptr) \ - ({ __typeof__(*(ptr)) __tmp = (val); \ - memmove((ptr), &__tmp, sizeof(*(ptr))); \ - (void)0; }) +#endif #endif /* __ASM_AVR32_UNALIGNED_H */ |