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author | Chris Zankel <czankel@tensilica.com> | 2005-06-23 22:01:26 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-24 00:05:22 -0700 |
commit | 9a8fd5589902153a134111ed7a40f9cca1f83254 (patch) | |
tree | 6f7a06de25bdf0b2d94623794c2cbbc66b5a77f6 /include/asm-xtensa/delay.h | |
parent | 3f65ce4d141e435e54c20ed2379d983d362a2cb5 (diff) | |
download | kernel_samsung_smdk4412-9a8fd5589902153a134111ed7a40f9cca1f83254.zip kernel_samsung_smdk4412-9a8fd5589902153a134111ed7a40f9cca1f83254.tar.gz kernel_samsung_smdk4412-9a8fd5589902153a134111ed7a40f9cca1f83254.tar.bz2 |
[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 6
The attached patches provides part 6 of an architecture implementation for the
Tensilica Xtensa CPU series.
Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-xtensa/delay.h')
-rw-r--r-- | include/asm-xtensa/delay.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/include/asm-xtensa/delay.h b/include/asm-xtensa/delay.h new file mode 100644 index 0000000..6359c55 --- /dev/null +++ b/include/asm-xtensa/delay.h @@ -0,0 +1,50 @@ +/* + * include/asm-xtensa/delay.h + * + * 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) 2001 - 2005 Tensilica Inc. + * + */ + +#ifndef _XTENSA_DELAY_H +#define _XTENSA_DELAY_H + +#include <linux/config.h> +#include <asm/processor.h> +#include <asm/param.h> + +extern unsigned long loops_per_jiffy; + +extern __inline__ void __delay(unsigned long loops) +{ + /* 2 cycles per loop. */ + __asm__ __volatile__ ("1: addi %0, %0, -2; bgeui %0, 1, 1b" + : "=r" (loops) : "0" (loops)); +} + +static __inline__ u32 xtensa_get_ccount(void) +{ + u32 ccount; + asm volatile ("rsr %0, 234; # CCOUNT\n" : "=r" (ccount)); + return ccount; +} + +/* For SMP/NUMA systems, change boot_cpu_data to something like + * local_cpu_data->... where local_cpu_data points to the current + * cpu. */ + +static __inline__ void udelay (unsigned long usecs) +{ + unsigned long start = xtensa_get_ccount(); + unsigned long cycles = usecs * (loops_per_jiffy / (1000000UL / HZ)); + + /* Note: all variables are unsigned (can wrap around)! */ + while (((unsigned long)xtensa_get_ccount()) - start < cycles) + ; +} + +#endif + |