| #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)); |
| } |
