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author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2009-05-23 23:18:40 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-05-23 23:18:40 +0100 |
commit | fc05505b77f7900a1bb74fb3f3a4343dee4265a4 (patch) | |
tree | 6517919cb60bd9465078512cacbefd8c77f94b76 /arch/xtensa/variants/s6000/delay.c | |
parent | a2ab67fae1ab9226679495a8d260f4e6555efc5f (diff) | |
parent | 11c79740d3c03cb81f84e98cf2e2dbd8d9bb53cd (diff) |
Merge branch 'ixp4xx' of git://git.kernel.org/pub/scm/linux/kernel/git/chris/linux-2.6 into devel
Diffstat (limited to 'arch/xtensa/variants/s6000/delay.c')
-rw-r--r-- | arch/xtensa/variants/s6000/delay.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/xtensa/variants/s6000/delay.c b/arch/xtensa/variants/s6000/delay.c new file mode 100644 index 00000000000..54b2b573f16 --- /dev/null +++ b/arch/xtensa/variants/s6000/delay.c @@ -0,0 +1,27 @@ +#include <asm/delay.h> +#include <asm/timex.h> +#include <asm/io.h> +#include <variant/hardware.h> + +#define LOOPS 10 +void platform_calibrate_ccount(void) +{ + u32 uninitialized_var(a); + u32 uninitialized_var(u); + u32 b; + u32 tstamp = S6_REG_GREG1 + S6_GREG1_GLOBAL_TIMER; + int i = LOOPS+1; + do { + u32 t = u; + asm volatile( + "1: l32i %0, %2, 0 ;" + " beq %0, %1, 1b ;" + : "=&a"(u) : "a"(t), "a"(tstamp)); + b = xtensa_get_ccount(); + if (i == LOOPS) + a = b; + } while (--i >= 0); + b -= a; + nsec_per_ccount = (LOOPS * 10000) / b; + ccount_per_jiffy = b * (100000UL / (LOOPS * HZ)); +} |