return cpu_khz_freq;
}
-
-
-
-#if 0
-
-
-/* ------ Calibrate the TSC -------
- * Return processor ticks per second / CALIBRATE_FRAC.
- *
- * Ported From Xen
- */
-#define PIT_MODE 0x43
-#define PIT_CH2 0x42
-#define CLOCK_TICK_RATE 1193180 /* system crystal frequency (Hz) */
-#define CALIBRATE_FRAC 20 /* calibrate over 50ms */
-#define CALIBRATE_LATCH ((CLOCK_TICK_RATE+(CALIBRATE_FRAC/2))/CALIBRATE_FRAC)
-
-
-unsigned long long get_cpu_khz() {
- ullong_t start, end;
- unsigned long count;
- unsigned long long tmp;
- unsigned long print_tmp;
-
- /* Set the Gate high, disable speaker */
- VM_Out_Byte((VM_In_Byte(0x61) & ~0x02) | 0x01, 0x61);
-
- /*
- * Now let's take care of CTC channel 2
- *
- * Set the Gate high, program CTC channel 2 for mode 0, (interrupt on
- * terminal count mode), binary count, load 5 * LATCH count, (LSB and MSB)
- * to begin countdown.
- */
- VM_Out_Byte(0xb0, PIT_MODE); /* binary, mode 0, LSB/MSB, Ch 2 */
- VM_Out_Byte(CALIBRATE_LATCH & 0xff, PIT_CH2); /* LSB of count */
- VM_Out_Byte(CALIBRATE_LATCH >> 8, PIT_CH2); /* MSB of count */
-
- rdtscll(start);
- for ( count = 0; (VM_In_Byte(0x61) & 0x20) == 0; count++ )
- continue;
- rdtscll(end);
-
- /* Error if the CTC doesn't behave itself. */
- if ( count == 0 ) {
- PrintBoth("CPU Frequency Calibration Error\n");
- return 0;
- }
-
- tmp = ((end - start) * (ullong_t)CALIBRATE_FRAC);
-
- do_div(tmp, 1000);
-
- tmp &= 0xffffffff;
- print_tmp = (unsigned long)tmp;
-
- PrintBoth("Detected %lu.%lu MHz CPU\n", print_tmp / 1000, print_tmp % 1000);
- return tmp;
-}
-
-#undef PIT_CH2
-#undef PIT_MODE
-#undef CLOCK_TICK_RATE
-#undef CALIBRATE_FRAC
-#undef CALIBRATE_LATCH
-
-#endif
