From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH] UEFI: Don't use UEFI time services on 32-bit Date: Tue, 10 Dec 2013 15:51:49 -0800 Message-ID: <52A7A915.1070701@zytor.com> References: <1385754283-2464-1-git-send-email-matthew.garrett@nebula.com> <52994324.4000404@zytor.com> <52A79B9A.7080004@zytor.com> <1386716246.26245.2.camel@x230> <52A7A1B0.7050903@zytor.com> <1386717862.26245.5.camel@x230> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1386717862.26245.5.camel@x230> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Matthew Garrett Cc: "linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" List-Id: linux-efi@vger.kernel.org On 12/10/2013 03:24 PM, Matthew Garrett wrote: >> >> 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. > Well, *which version* of Windows is a big question here. Keep in mind that the TAD was only introduced with ACPI 5 so it is quite a new feature. I would really like to see it implemented in SeaBIOS and/or OVMF so we can test it out in Qemu. -hpa