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author | Simon Horman <horms@verge.net.au> | 2008-09-10 09:14:52 +1000 |
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committer | Simon Horman <horms@verge.net.au> | 2008-09-10 09:14:52 +1000 |
commit | c051a0a2c9e283c1123ed3ce65e66e41d2ce5e24 (patch) | |
tree | 1202d018129ca5538cd98b1e4542b239045c1a2d /arch/blackfin/include/asm/delay.h | |
parent | e9c0ce232e7a36daae1ca08282609d7f0c57c567 (diff) | |
parent | 28faa979746b2352cd78a376bf9f52db953bda46 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 into lvs-next-2.6
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 |