lkml.org 
[lkml]   [2013]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: CONFIG_RTC_HCTOSYS lost on x86 with ALWAYS_USE_PERSISTENT_CLOCK changes?
On 04/25/2013 12:11 AM, Alexander Holler wrote:
> Am 24.04.2013 18:07, schrieb John Stultz:
>
>>> And why is RTC_SYSTOHC now gone on x86?
>>
>> So summarizing the above, because as much as I'm aware, its always been
>> redundant and unnecessary on x86. Thus being able at build time to mark
>> it as unnecessary was attractive, since it reduced the code paths
>> running at suspend/resume.
>
> Hmm, I thought RTC_SYSTOHC was there to update the used RTC clock with
> the time from NTP (and liked that). Therefor I don't understand why it
> is redundant and unnecessary on x86. Of course, most systems do have
> something in userspace to set the RTC on shutdown, so it isn't really
> needed.

Prior to SYSTOHC being introduced, we only synced system time to the RTC
via update_persistent_clock() on systems that had that interface.
SYSTOHC is relatively new and lets the system sync to RTCs that don't
have the persistent clock.

thanks
-john



\
 
 \ /
  Last update: 2013-04-25 18:21    [W:0.078 / U:0.712 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site