I'm writing a driver for the RAPL MSRs and have come across the following in the documentation:
"MSR_PKG_RAPL_PERF_STATUS can report performance impact of power limiting, but its availability may be model-specific."
[pg 14-30, v3B, Oct. 2011]
1) This is listed as MSR_PKG_PERF_STATUS in table 34-10 [pg 34-158 v3C Oct. 2011]. Please fix.
2) I'm getting an I/O error when trying to read this MSR (0x613). The rest of the PKG MSRs are fine, so I'm guessing this is confirmation that MSR_PKG_PERF_STATUS isn't available on my dev machine [family=6, model=42, stepping=7].
3) I'm targetting this driver for the Xeon version of Sandy Bridge. I think I heard that we're getting the C revision. Will it be available there? Does anyone have a chart showing which steppings have this enabled?
RTFM is a welcome answer so long as a pointer is given to which FM I should R.
For information on this particular matter, I would suggest contacting a Field Application Engineer (FAE), you can contact any of them by calling our local Authorized Intel® Distributors and asking for a FAE.
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Regarding information on new processor released, currently we can only comment on released products, this is because the information on non-released products will be available until the day it is released.