diff options
| author | Atsushi Nemoto <anemo@mba.ocn.ne.jp> | 2008-09-01 22:22:37 +0900 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2008-10-11 16:18:47 +0100 |
| commit | 21e77df215e58523a755b5dd006cb17610616f20 (patch) | |
| tree | 94895b0fdc98e5f6ac44ba667feb96a9433a7065 /include/asm-mips | |
| parent | f6d9831bb11eb465f95fb1736b866d405d9c7cbf (diff) | |
| download | linux-21e77df215e58523a755b5dd006cb17610616f20.tar.bz2 | |
MIPS: TXx9: Microoptimize interrupt handlers
The IOC interrupt status register on RBTX49XX only have 8 bits. Use
8-bit version of __fls() to optimize interrupt handlers.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'include/asm-mips')
| -rw-r--r-- | include/asm-mips/txx9/generic.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/include/asm-mips/txx9/generic.h b/include/asm-mips/txx9/generic.h index 1e1a9f2d2379..dc85515eac13 100644 --- a/include/asm-mips/txx9/generic.h +++ b/include/asm-mips/txx9/generic.h @@ -64,4 +64,22 @@ struct physmap_flash_data; void txx9_physmap_flash_init(int no, unsigned long addr, unsigned long size, const struct physmap_flash_data *pdata); +/* 8 bit version of __fls(): find first bit set (returns 0..7) */ +static inline unsigned int __fls8(unsigned char x) +{ + int r = 7; + + if (!(x & 0xf0)) { + r -= 4; + x <<= 4; + } + if (!(x & 0xc0)) { + r -= 2; + x <<= 2; + } + if (!(x & 0x80)) + r -= 1; + return r; +} + #endif /* __ASM_TXX9_GENERIC_H */ |