diff options
author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2008-10-09 21:31:56 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-10-09 21:31:56 +0100 |
commit | 6a4690c22f5da1eb1c898b61b6a80da52fbd976f (patch) | |
tree | a03891a32abe0da191fb765fe669a597e07423c6 /arch/blackfin/include/asm/delay.h | |
parent | 90bb28b0644f7324f8bd1feb27b35146e6785ba2 (diff) | |
parent | 8ec53663d2698076468b3e1edc4e1b418bd54de3 (diff) |
Merge branch 'ptebits' into devel
Conflicts:
arch/arm/Kconfig
Diffstat (limited to 'arch/blackfin/include/asm/delay.h')
-rw-r--r-- | arch/blackfin/include/asm/delay.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/delay.h b/arch/blackfin/include/asm/delay.h new file mode 100644 index 00000000000..0889c3abb59 --- /dev/null +++ b/arch/blackfin/include/asm/delay.h @@ -0,0 +1,62 @@ +/* + * delay.h - delay functions + * + * Copyright (c) 2004-2007 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#ifndef __ASM_DELAY_H__ +#define __ASM_DELAY_H__ + +#include <mach/anomaly.h> + +static inline void __delay(unsigned long loops) +{ + if (ANOMALY_05000312) { + /* Interrupted loads to loop registers -> bad */ + unsigned long tmp; + __asm__ __volatile__( + "[--SP] = LC0;" + "[--SP] = LT0;" + "[--SP] = LB0;" + "LSETUP (1f,1f) LC0 = %1;" + "1: NOP;" + /* We take advantage of the fact that LC0 is 0 at + * the end of the loop. Otherwise we'd need some + * NOPs after the CLI here. + */ + "CLI %0;" + "LB0 = [SP++];" + "LT0 = [SP++];" + "LC0 = [SP++];" + "STI %0;" + : "=d" (tmp) + : "a" (loops) + ); + } else + __asm__ __volatile__ ( + "LSETUP(1f, 1f) LC0 = %0;" + "1: NOP;" + : + : "a" (loops) + : "LT0", "LB0", "LC0" + ); +} + +#include <linux/param.h> /* needed for HZ */ + +/* + * 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) + */ +static inline void udelay(unsigned long usecs) +{ + extern unsigned long loops_per_jiffy; + __delay(usecs * loops_per_jiffy / (1000000 / HZ)); +} + +#endif |