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author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2008-08-02 13:55:55 +0400 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-08-03 00:32:35 +0400 |
commit | 4baa9922430662431231ac637adedddbb0cfb2d7 (patch) | |
tree | e8fb765ce3e41c01f33de34a0bc9494f0ae19818 /arch/arm/include/asm/delay.h | |
parent | ff4db0a043a5dee7180bdffd178e61cd02812c68 (diff) | |
download | linux-4baa9922430662431231ac637adedddbb0cfb2d7.tar.xz |
[ARM] move include/asm-arm to arch/arm/include/asm
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/delay.h')
-rw-r--r-- | arch/arm/include/asm/delay.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/arm/include/asm/delay.h b/arch/arm/include/asm/delay.h new file mode 100644 index 000000000000..b2deda181549 --- /dev/null +++ b/arch/arm/include/asm/delay.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 1995-2004 Russell King + * + * Delay routines, using a pre-computed "loops_per_second" value. + */ +#ifndef __ASM_ARM_DELAY_H +#define __ASM_ARM_DELAY_H + +#include <asm/param.h> /* HZ */ + +extern void __delay(int loops); + +/* + * This function intentionally does not exist; if you see references to + * it, it means that you're calling udelay() with an out of range value. + * + * With currently imposed limits, this means that we support a max delay + * of 2000us. Further limits: HZ<=1000 and bogomips<=3355 + */ +extern void __bad_udelay(void); + +/* + * division by multiplication: you don't have to worry about + * loss of precision. + * + * Use only for very small delays ( < 1 msec). Should probably use a + * lookup table, really, as the multiplications take much too long with + * short delays. This is a "reasonable" implementation, though (and the + * first constant multiplications gets optimized away if the delay is + * a constant) + */ +extern void __udelay(unsigned long usecs); +extern void __const_udelay(unsigned long); + +#define MAX_UDELAY_MS 2 + +#define udelay(n) \ + (__builtin_constant_p(n) ? \ + ((n) > (MAX_UDELAY_MS * 1000) ? __bad_udelay() : \ + __const_udelay((n) * ((2199023U*HZ)>>11))) : \ + __udelay(n)) + +#endif /* defined(_ARM_DELAY_H) */ + |