From 21e77df215e58523a755b5dd006cb17610616f20 Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Mon, 1 Sep 2008 22:22:37 +0900 Subject: 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 Signed-off-by: Ralf Baechle --- include/asm-mips/txx9/generic.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include') diff --git a/include/asm-mips/txx9/generic.h b/include/asm-mips/txx9/generic.h index 1e1a9f2d237..dc85515eac1 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 */ -- cgit v1.2.3