tscfix - Fix Time-Stamp counter on x86 machines with a bad BIOS

Introduction

Some x86 machines (e.g. the notorious DX79TO) have a BIOS bug that scrambles their time-stamp counter (TSC) even though their processor's TSC is otherwise reliable. This forces the kernel to use slower time sources, such as HPET.

tscfix attempts to work around this issue by re-synchronizing the TSC.

How to use

1. Build and install tscadj
2. Build tscfix (make)
3. Run tscfix once to view tsc skew
4. Run tscfix -f as root to attempt to correct the skew
5. Run tscfix again to verify that the skew has been eliminated. A few dozen cycles of skew is permissable.
6. Use kexec to reboot your kernel without going through the BIOS:

kexec -l /path/to/kernel --initrd /path/to/initrd --reuse-cmdline --append tsc=reliable
kexec -e

(as root)