From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH 1/3] rtc-efi: register rtc-efi device when EFI enabled Date: Fri, 28 Dec 2012 17:07:37 -0800 Message-ID: <50DE4259.7090409@zytor.com> References: <1356712001-12198-1-git-send-email-jlee@suse.com> <1356742803.6113.245.camel@linux-s257.site> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1356742803.6113.245.camel-ONCj+Eqt86TasUa73XJKwA@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: joeyli Cc: Matthew Garrett , "matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Thomas Gleixner , Ingo Molnar , Jan Beulich List-Id: linux-efi@vger.kernel.org On 12/28/2012 05:00 PM, joeyli wrote: > =E6=96=BC =E4=BA=94=EF=BC=8C2012-12-28 =E6=96=BC 17:43 +0000=EF=BC=8C= Matthew Garrett =E6=8F=90=E5=88=B0=EF=BC=9A >> On Sat, 2012-12-29 at 00:26 +0800, Lee, Chun-Yi wrote: >>> UEFI time services, GetTime(), SetTime(), GetWakeupTime(), SetWakeu= pTime() are also >>> supported by other non-IA64 architecutre with UEFI BIOS, e.g. x86. >>> >>> This patch changed RTC_DRV_EFI configuration to depend on EFI but n= ot just IA64. It >>> checks efi_enabled flag and efi-rtc driver should enabled. >> >> In theory, certainly - but do we still have machines that explode if= the >> get_time call is made? We may also want to think about disabling the >> legacy access to the RTC if the EFI calls are present. >=20 > The legacy get_time access on my test machine is work fine, not thing > explode. :-) > Just we have a function want to expose the timezone information to > userspace and also store it. >=20 We should indeed save the timezone information if it is available -- either from the ACPI TAD or from the EFI RTC, or even via some platform-dependent mechanism. It is important, though, that that is separate from the order of priority. -hpa From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755205Ab2L2BIJ (ORCPT ); Fri, 28 Dec 2012 20:08:09 -0500 Received: from terminus.zytor.com ([198.137.202.10]:40054 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755077Ab2L2BIH (ORCPT ); Fri, 28 Dec 2012 20:08:07 -0500 Message-ID: <50DE4259.7090409@zytor.com> Date: Fri, 28 Dec 2012 17:07:37 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: joeyli CC: Matthew Garrett , "matt.fleming@intel.com" , "linux-kernel@vger.kernel.org" , "linux-efi@vger.kernel.org" , Thomas Gleixner , Ingo Molnar , Jan Beulich Subject: Re: [PATCH 1/3] rtc-efi: register rtc-efi device when EFI enabled References: <1356712001-12198-1-git-send-email-jlee@suse.com> <1356742803.6113.245.camel@linux-s257.site> In-Reply-To: <1356742803.6113.245.camel@linux-s257.site> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/28/2012 05:00 PM, joeyli wrote: > 於 五，2012-12-28 於 17:43 +0000，Matthew Garrett 提到： >> On Sat, 2012-12-29 at 00:26 +0800, Lee, Chun-Yi wrote: >>> UEFI time services, GetTime(), SetTime(), GetWakeupTime(), SetWakeupTime() are also >>> supported by other non-IA64 architecutre with UEFI BIOS, e.g. x86. >>> >>> This patch changed RTC_DRV_EFI configuration to depend on EFI but not just IA64. It >>> checks efi_enabled flag and efi-rtc driver should enabled. >> >> In theory, certainly - but do we still have machines that explode if the >> get_time call is made? We may also want to think about disabling the >> legacy access to the RTC if the EFI calls are present. > > The legacy get_time access on my test machine is work fine, not thing > explode. :-) > Just we have a function want to expose the timezone information to > userspace and also store it. > We should indeed save the timezone information if it is available -- either from the ACPI TAD or from the EFI RTC, or even via some platform-dependent mechanism. It is important, though, that that is separate from the order of priority. -hpa