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Subject: Re: [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME
From: joeyli <jlee@suse.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Alessandro Zummo <a.zummo@towertech.it>,
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        "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
        linux-acpi@vger.kernel.org, Borislav Petkov <bp@suse.de>
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Date: Fri, 20 Dec 2013 12:05:57 +0800
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於 四，2013-12-19 於 06:59 -0800，H. Peter Anvin 提到：
> On 12/18/2013 11:43 PM, Lee, Chun-Yi wrote:
> > This patchset add the timezone support of ACPI TAD and EFI TIME, it
> > also add codes for adjusting system time base on the timezone value
> > from EFI TIME services when system boot.
> 
> EFI time is something we used to support and ripped out, because it
> doesn't work well, *at all*.
> 
> I am hyper-skeptical to reintroducing them, and *definitely* will veto
> reintroducing them on a system which has PNP0B0x devices present.
> 
> 	-hpa
> 

Then that means the priority of PNP0B0x is higher then "CMOS RTC Not
Present" flag. ACPI spec doesn't have clear definition on this.

I look forward to Borislav's "EFI runtime mapping" to fix the physical
address accessing issue of EFI time service on x86_64 machines. I tested
his patches on a issue machine and it works for walk around BIOS bug.

Can we use EFI time services on x86_64 after Borislav's patches accepted
to mainline?


Thanks a lot!
Joey Lee