[coreboot] [PATCH] RFC AMD powernow generation for pre fam 0fh

Marc Jones marcj303 at gmail.com
Mon Dec 27 21:36:02 CET 2010

2010/12/25 Rudolf Marek <r.marek at assembler.cz>:
> Hi all,
> This is RFC patch. It adds support for automatic PSS object generation for
> AMD pre fam Fh CPU. Those CPUs require a hardcoded table, which I managed to
> rewrite during one particularly boring flight. Too pity it is only for
> Opteron CPUs. Someone needs to finish the second PDF for All others Athlons
> and Semprons.
> It just adds the table to same place where is the fam0fh generator. To make
> the powernow work on my Asrock 939 board I had to enable undocumented bit1
> in PM_Misc 67h of SB710. It looks like this bit is documented in SB600 and
> it is doing LDT_STOP toggle for C states (and for FID/VID). I remember I had
> to fix this toggle for VIA chipset too. It took me some time to figure it
> out. It helped that it started to work if the orig bios was booted and
> halted to S5.
> All search was to find out what register was not  updated by coreboot).
> Whom to ask to fix the AMD documentation?

Hi Rudolf,

I don't know if this is the case for this bit, but some registers are
only documented in the register programming requirements document
(rpr) and not in the register reference guide (rrg). This is
intentional by AMD and they probably won't be changed.

Frank Vibrans is on this list and should be able to relay the request
back to the document gatekeepers next week, when they get back from
the holiday shutdown.



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