On 2014-11-12 03:23:04, Laszlo Ersek wrote:
> On 11/11/14 22:34, Gabriel Somlo wrote:
> > On Sun, Nov 09, 2014 at 10:13:54AM -0800, Jordan Justen wrote:
> >> On 2014-11-08 14:02:00, Gabriel L. Somlo wrote:
> >>> Since in OVMF both PEI_CORE and PEIM run from RAM, and thus may
> >>> utilize global variables, use the "Base" AcpiTimerLib instance
> >>> (instead of BaseRom) to take advantage of the improved efficiency
> >>> of storing the timer register IO address in a global variable.
> >>>
> >>> This leaves only SEC using the BaseRomAcpiTimerLib instance.
> >>>
> >>> Contributed-under: TianoCore Contribution Agreement 1.0
> >>> Signed-off-by: Gabriel Somlo <so...@cmu.edu>
> >>> ---
> >>>
> >>> [...]
> >>>
> >>> + //
> >>> + // Check to see if the Power Management Base Address is already enabled
> >>> + //
> >>> + if ((PciRead8 (PmRegMisc) & PMIOSE) == 0) {
> >>> + //
> >>> + // If the Power Management Base Address is not programmed,
> >>> + // then program the Power Management Base Address from a PCD.
> >>> + //
> >>> + PciAndThenOr32 (Pmba, (UINT32) ~0xFFC0, PcdGet16
> >>> (PcdAcpiPmBaseAddress));
> >>> +
> >>> + //
> >>> + // Enable PMBA I/O port decodes in PMREGMISC
> >>> + //
> >>> + PciOr8 (PmRegMisc, PMIOSE);
> >>
> >> Wouldn't the 'Rom' version program this during SEC?
> >>
> >> I don't think we should access the PCD in BaseAcpiTimerLib.
> >
> > I seem to remember someone earlier in the thread mentioning that it's
> > possible for SEC *not* to run, in which case it's PEI's job to enable
> > PMBA. Laszlo ? :)
>
> SEC always runs, but whether or not SEC depends on TimerLib is
> conditional on -D SOURCE_DEBUG_ENABLE. If it is absent, then the debug
> agent is not pulled in (*), and then SEC doesn't inherit the TimerLib
> dependency, and the BaseRomAcpiTimerLib constructor won't run in SEC.
>
> (*) Meaning, DebugAgentLib is resolved to DebugAgentLibNull as opposed
> to SecPeiDebugAgentLib.
>
> Please see
> <http://thread.gmane.org/gmane.comp.bios.tianocore.devel/10859/focus=10897>.
>
> Jordan -- can you please go through that message, and see if you agree.
> If we disagree on points in that message, we need to sort out that
> first; otherwise we'll jerk Gabriel in different directions.
I guess the biggest thing that struck me as odd was that
BaseAcpiTimerLib was reading the PCD. Shouldn't that only happen in
the Dxe version?
Too bad the DebugAgent isn't actually useful for all the trouble it
causes. :)
-Jordan
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