Avi Kivity wrote: > Alexander Graf wrote: >> This is a resend of a mail I sent on 01/10/2008. I did not receive any >> response, so I assume it was lost. >> >> The patch is really minor, does not break any compatibility (the MSR is >> Intel family 13+) and makes Darwin work. >> >> --- old mail --- >> >> This patch adds support for the MSR MSR_IA32_PERF_STATUS. This is >> required to boot Darwin. >> >> I only implemented dummy support, as the real value would be of no >> meaning to any OS I know so far anyway and is only implemented on very >> recent Intel CPUs. >> > > I see some documentation of this in 13.1.1, but is there somewhere > with more information? > The only proper source of information I found was the XNU kernel, which implements a full interpretation of the MSR values. Basically the high bits are the CPU multiplier, while the low bits represent the number the TSC advances in one cycle.
There is also a bit which multiplies everything by 2, but maybe the Intel people on this list can tell us more about it. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/kvm-devel
