[LinuxBIOS] mcp55 flashrom problem
Carl-Daniel Hailfinger
c-d.hailfinger.devel.2006 at gmx.net
Mon Mar 5 17:53:52 CET 2007
On 05.03.2007 17:37, Ward Vandewege wrote:
> On Sat, Mar 03, 2007 at 07:09:15PM +0100, Stefan Reinauer wrote:
>> Can you please observe the changes over several consequtive reboots (5
>> or so)
>
> This is it. The first line is the 'baseline' - the image I retrieved with the
> proprietary in-bios qflash tool, last Friday. All the other lines are
> consecutive reboots today; I wrote a script to dump the flash with flashrom,
> diff it, and reboot - each of these lines is roughly a couple of minutes
> apart.
>
> -0000fd90 0f 00 24 00 12 00 00 02 03 07 00 00 40 00 00 00
^^ ^^ ^^ ^^
|| || || unknown
|| || ++-most significant byte of counter
|| ++-medium significant byte of counter
++-least significant byte of counter
> +0000fd90 0a 00 00 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 16 00 1c 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 14 00 25 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 14 00 27 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 08 00 29 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 39 00 2a 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 2e 00 2c 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 16 00 31 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 0b 00 33 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 00 00 35 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 32 00 36 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 28 00 38 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 0e 00 3b 00 0f 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 36 00 02 00 10 00 00 05 03 07 00 00 40 00 00 00
> +0000fd90 2c 00 04 00 10 00 00 05 03 07 00 00 40 00 00 00
>
> What do you make of this?
A counter with 6 bits per byte and one unknown byte. Note how no
value is >=0x40 and a wraparound of the second value increases
the third value by 1?
Could be a timer, e.g. boot time or something like that. Try
to correlate boot time intervals with the differences in the
counter.
Regards,
Carl-Daniel
--
http://www.hailfinger.org/
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