Re: [PATCH] UEFI: Don't use UEFI time services on 32-bit

[Matthew Garrett <matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>]

On Tue, 2013-12-10 at 15:20 -0800, H. Peter Anvin wrote:
> On 12/10/2013 02:58 PM, Matthew Garrett wrote:
> > EFI is preferable to PNP in that it gives us a timezone, and Windows
> > certainly calls the EFI time functions. *However*, it doesn't appear to
> > do so once the system is booted. So we probably want to call it in the
> > boot stub and find some way to pass the timezone information up to the
> > kernel, and then spend some more time instrumenting Windows to figure
> > out how it makes time calls.
> 
> TAD would also give us the timezone.  I'm not sure how you can
> realistically only use the time function during boot, however, unless
> you inherently assume it is coherent with the hardware RTC, since you
> wouldn't be able to set it.

If we can verify that Windows actually uses TAD then I'd agree it's
preferable to EFI, but if we can't then I wouldn't be so sure. I'll redo
my Windows instrumentation and figure out under which circumstances it's
calling the time functions.

-- 
Matthew Garrett <matthew.garrett@nebula.com>