Calculate TSC frequency.\r
\r
The TSC counting frequency is determined by comparing how far it counts\r
- during a 100us period as determined by the ACPI timer. The ACPI timer is\r
- used because it counts at a known frequency.\r
- The TSC is sampled, followed by waiting for ACPI_TIMER_FREQUENCY / 10000\r
- clocks of the ACPI timer, or 100us. The TSC is then sampled again. The\r
- difference multiplied by 10000 is the TSC frequency. There will be a small\r
- error because of the overhead of reading the ACPI timer. An attempt is\r
- made to determine and compensate for this error.\r
+ during a 101.4 us period as determined by the ACPI timer.\r
+ The ACPI timer is used because it counts at a known frequency.\r
+ The TSC is sampled, followed by waiting 363 counts of the ACPI timer,\r
+ or 101.4 us. The TSC is then sampled again. The difference multiplied by\r
+ 9861 is the TSC frequency. There will be a small error because of the\r
+ overhead of reading the ACPI timer. An attempt is made to determine and\r
+ compensate for this error.\r
\r
@return The number of TSC counts per second.\r
\r