lkml.org 
[lkml]   [2013]   [Jul]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] RTC: Add an alarm disable quirk
    On 07/19/2013 08:13 AM, Borislav Petkov wrote:
    > On Fri, Jul 19, 2013 at 04:26:28PM +0200, Borislav Petkov wrote:
    >> On Fri, Jul 19, 2013 at 12:53:49AM +0200, Borislav Petkov wrote:
    >>>> I assumed it was some sort of BIOS issue where any modification of the
    >>>> RTC_AIE bit caused the alarm irq line to be left high(or something
    >>>> like that) that triggered the immediate power-on on shutdown. But I've
    >>>> not been able to dig down on this.
    >>> Ha, this actually fits like an ass on a bucket (don't ask - German
    >>> proverb :-)).
    >>>
    >>> If what you're saying is actually the case, then this explains why not
    >>> writing to 0xb doesn't cause the alarm irq to fire.
    >>>
    >>> Btw, in the trace above we do the disabling twice. Once from
    >>> rtc_timer_remove() and then again from rtc_timer_do_work().
    >>>
    >>> So, if we disable it once and we touch RTC_AIE again causing the second
    >>> time to rearm the alarm irq, this would explain the issue. Which reminds
    >>> me:
    >>>
    >>> Maybe we should read out the alarm interrupt first and disable it only
    >>> if it is enabled - that would save us the modification of RTC_AIE. Cool,
    >>> I'll try that tomorrow.
    >> Well, the below seems to do the trick. But since I don't trust the BIOS
    >> in any way, I'll run it a couple more days here. Btw, I think we should
    >> commit this regardless, as it saves us unneeded writes:
    > Nope, this doesn't help - box just rebooted. :(
    >
    > So I'm back to the DMI quirk patch...

    So did this work some of the time, but not all? Or was the behavior
    totally unchanged with this?

    thanks
    -john


    \
     
     \ /
      Last update: 2013-07-22 23:21    [W:3.473 / U:0.000 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site