diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-08 09:22:53 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-08 09:22:53 -0700 |
commit | 46056be71c37378f518711da651e4bb76d650ee9 (patch) | |
tree | 63c563bc3b84f22b517114ebb101b991958228a4 /arch/mips/lib/delay.c | |
parent | 5284c6b99ea017f73c09b50f34a637ff9d5d26a0 (diff) | |
parent | 5636919b5c909fee54a6ef5226475ecae012ad02 (diff) | |
download | linux-3.10-46056be71c37378f518711da651e4bb76d650ee9.tar.gz linux-3.10-46056be71c37378f518711da651e4bb76d650ee9.tar.bz2 linux-3.10-46056be71c37378f518711da651e4bb76d650ee9.zip |
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
MIPS: Outline udelay and fix a few issues.
MIPS: ioctl.h: Fix headers_check warnings
MIPS: Cobalt: PCI bus is always required to obtain the board ID
MIPS: Kconfig: Remove "Support for" from Cavium system type
MIPS: Sibyte: Honor CONFIG_CMDLINE
SSB: BCM47xx: Export ssb_watchdog_timer_set
Diffstat (limited to 'arch/mips/lib/delay.c')
-rw-r--r-- | arch/mips/lib/delay.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/mips/lib/delay.c b/arch/mips/lib/delay.c new file mode 100644 index 00000000000..f69c6b569eb --- /dev/null +++ b/arch/mips/lib/delay.c @@ -0,0 +1,56 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1994 by Waldorf Electronics + * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle + * Copyright (C) 1999, 2000 Silicon Graphics, Inc. + * Copyright (C) 2007 Maciej W. Rozycki + */ +#include <linux/module.h> +#include <linux/param.h> +#include <linux/smp.h> + +#include <asm/compiler.h> +#include <asm/war.h> + +inline void __delay(unsigned int loops) +{ + __asm__ __volatile__ ( + " .set noreorder \n" + " .align 3 \n" + "1: bnez %0, 1b \n" + " subu %0, 1 \n" + " .set reorder \n" + : "=r" (loops) + : "0" (loops)); +} +EXPORT_SYMBOL(__delay); + +/* + * 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) + */ + +void __udelay(unsigned long us) +{ + unsigned int lpj = current_cpu_data.udelay_val; + + __delay((us * 0x000010c7 * HZ * lpj) >> 32); +} +EXPORT_SYMBOL(__udelay); + +void __ndelay(unsigned long ns) +{ + unsigned int lpj = current_cpu_data.udelay_val; + + __delay((us * 0x00000005 * HZ * lpj) >> 32); +} +EXPORT_SYMBOL(__ndelay); |