RTC anti-rollback testing

Mitch Bradley wmb at laptop.org
Fri Oct 14 13:26:35 EDT 2011

The most likely explanation is that OFW had to power off in order to 
re-enable writing to the SPI FLASH.  That can happen if the last reboot 
was from Linux.  See http://dev.laptop.org/ticket/4397

Unless that bug is fixed, the process will be:

a) Linux reboots
b) OFW runs rtc-rollback? and tries to write the new timestamp SPI FLASH
c) OFW is unable to perform the write because SPI FLASH is locked
d) OFW reboots, using the EC command that unlocks SPI FLASH
e) OFW runs rtc-rollback? and sucessfully writes the new timestamp'

The net result is that reboots will take slightly longer when 
anti-rollback is enabled.

On 10/14/2011 2:53 AM, Esteban Bordón wrote:
> 2011/10/11 Esteban Bordón <ebordon at plan.ceibal.edu.uy 
> <mailto:ebordon at plan.ceibal.edu.uy>>
>     Hi all,
>     I'm trying to test the RTCAR including on OFW Q2E46 by following
>     the steps indicated in
>     http://wiki.laptop.org/go/RTC_Anti-rollback#Testing_Rollback_Detection.
>     I added the "rt" tag, but when I run command
>     ok rtc-rollback? .
>     the laptop powers off.
>     Is it a normal behaviour?
>     cheers,
>     Esteban
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