Re: [RFC PATCH 00/14] Support timezone of ACPI TAD and EFI TIME

joeyli
2013-12-20T05:38:36Z

於 四，2013-12-19 於 20:22 -0800，H. Peter Anvin 提到：
> On 12/19/2013 08:05 PM, joeyli wrote:
> >
> > Then that means the priority of PNP0B0x is higher then "CMOS RTC Not
> > Present" flag. ACPI spec doesn't have clear definition on this.
> >
>
> According to the Microsoft requirements documents, such a platform is
> broken and shouldn't exist.

OK~~

>
> > 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?
> >
>
> No.
>
> -hpa

If don't use EFI time, then the first priority is using ACPI TAD if it
present. Due to ACPI TAD is a generic acpi device that's need OS parsing
DSDT table before set system time.

Either move DSDT parser from subsystem initial stage to start_kernel or
move timekeeping initial to after DSDT be parsed. Which one you think is
more possible and risk less? Then I will try that way.

Thanks a lot!
Joey Lee