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#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));
}
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