From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
To: Matthew Garrett
<matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>
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<matt-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
Subject: Re: [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME
Date: Fri, 20 Dec 2013 13:12:52 -0800 [thread overview]
Message-ID: <52B4B2D4.2020305@zytor.com> (raw)
In-Reply-To: <1387552565.17961.3.camel@x230>
On 12/20/2013 07:16 AM, Matthew Garrett wrote:
> On Thu, 2013-12-19 at 20:22 -0800, H. Peter Anvin wrote:
>> On 12/19/2013 08:05 PM, joeyli wrote:
>>> Can we use EFI time services on x86_64 after Borislav's patches accepted
>>> to mainline?
>>>
>>
>> No.
>
> We will want to use them to (at minimum) obtain the clock timezone.
> Using them for general RTC access is less attractive.
>
One option is to use the EFI runtime call to get and save the clock
timezone before we call ExitBootServices() in the EFI stub. This
doesn't obviate the need for proper handling of the TAD, though,
especially since it is likely that future hardware will not have a RTC
in the current form (it is a way more complex device than is needed,
which wouldn't normally be a problem, but the fact that it has to
operate in the Vbat well makes it a major one.)
-hpa
next prev parent reply other threads:[~2013-12-20 21:12 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-19 7:43 [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME Lee, Chun-Yi
[not found] ` <1387439053-8711-1-git-send-email-jlee-IBi9RG/b67k@public.gmane.org>
2013-12-19 7:44 ` [PATCH 01/14] rtc-efi: fix decrease day twice when computing year days Lee, Chun-Yi
2013-12-19 7:44 ` [PATCH 03/14] rtc: block registration of rtc-cmos when CMOS RTC Not Present Lee, Chun-Yi
[not found] ` <1387439053-8711-4-git-send-email-jlee-IBi9RG/b67k@public.gmane.org>
2013-12-19 14:38 ` H. Peter Anvin
[not found] ` <6fc9a2f9-eae7-4588-a092-f338053ec96a-2ueSQiBKiTY7tOexoI0I+QC/G2K4zDHf@public.gmane.org>
2013-12-20 3:54 ` joeyli
2013-12-20 4:20 ` H. Peter Anvin
2013-12-19 14:59 ` [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME H. Peter Anvin
[not found] ` <52B309EB.90300-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
2013-12-19 16:04 ` Alessandro Zummo
2013-12-20 4:05 ` joeyli
[not found] ` <1387512357.3539.4317.camel-ONCj+Eqt86TasUa73XJKwA@public.gmane.org>
2013-12-20 4:22 ` H. Peter Anvin
[not found] ` <52B3C5F0.1060303-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
2013-12-20 5:38 ` joeyli
[not found] ` <1387517916.3539.4446.camel-ONCj+Eqt86TasUa73XJKwA@public.gmane.org>
2013-12-20 21:10 ` H. Peter Anvin
[not found] ` <52B4B242.5010002-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
2013-12-20 21:25 ` H. Peter Anvin
2013-12-20 21:45 ` Rafael J. Wysocki
2013-12-20 21:43 ` H. Peter Anvin
[not found] ` <52B4BA0A.1030902-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
2013-12-20 21:50 ` Matt Fleming
[not found] ` <20131220215056.GA29501-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
2013-12-20 22:18 ` Rafael J. Wysocki
[not found] ` <3476450.BMEcId2Lgj-sKB8Sp2ER+y1GS7QM15AGw@public.gmane.org>
2013-12-21 12:21 ` Matt Fleming
2014-01-12 0:30 ` [RFT][PATCH] ACPI / init: Run acpi_early_init() before efi_enter_virtual_mode() (was: Re: [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME) Rafael J. Wysocki
[not found] ` <2530951.HFPX8MI38t-sKB8Sp2ER+y1GS7QM15AGw@public.gmane.org>
2014-01-12 9:06 ` Borislav Petkov
2014-01-14 2:04 ` Toshi Kani
[not found] ` <1389665096.1792.271.camel-RbGIw1UOYPVo/CpIj0byZw@public.gmane.org>
2014-01-14 16:25 ` Toshi Kani
2014-01-12 11:05 ` Matt Fleming
2014-01-17 12:20 ` Matt Fleming
2014-01-14 4:09 ` joeyli
[not found] ` <1389672548.24105.252.camel-ONCj+Eqt86TasUa73XJKwA@public.gmane.org>
2014-01-14 16:50 ` Rafael J. Wysocki
2014-01-14 18:00 ` [RFT][PATCH] ACPI / init: Run acpi_early_init() before efi_enter_virtual_mode() H. Peter Anvin
2014-01-14 20:32 ` Toshi Kani
[not found] ` <1389731547.1792.296.camel-RbGIw1UOYPVo/CpIj0byZw@public.gmane.org>
2014-01-15 7:18 ` joeyli
[not found] ` <2787644.ytU7M33B4r-sKB8Sp2ER+y1GS7QM15AGw@public.gmane.org>
2013-12-21 2:43 ` [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME joeyli
2013-12-20 10:53 ` Thomas Renninger
2013-12-20 22:15 ` H. Peter Anvin
2013-12-20 15:16 ` Matthew Garrett
2013-12-20 16:57 ` H. Peter Anvin
2013-12-20 16:58 ` Matthew Garrett
2013-12-20 20:29 ` H. Peter Anvin
[not found] ` <a049daea-a713-4d06-b35f-61f3bec06ba9-2ueSQiBKiTY7tOexoI0I+QC/G2K4zDHf@public.gmane.org>
2013-12-20 20:32 ` Matthew Garrett
2013-12-20 21:14 ` H. Peter Anvin
2013-12-20 21:12 ` H. Peter Anvin [this message]
-- strict thread matches above, loose matches on Subject: below --
2013-12-19 7:51 Lee, Chun-Yi
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