Re: [PATCH 1/3] rtc-efi: register rtc-efi device when EFI enabled

["H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.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