[coreboot] dell s1850: 00e8 is important!

[Carl-Daniel Hailfinger]

On 06.10.2009 21:49, ron minnich wrote:
> On Tue, Oct 6, 2009 at 12:45 PM, Myles Watson <mylesgw at gmail.com> wrote:
>   
>>> here is post rest
>>> postreset:SerialICE-hlp: outl 00e8 <= 44656c6c
>>>       
>> Dell
>>     
>>> postreset:SerialICE-hlp: outl 00e8 <= 50726f74
>>>       
>> Prot
>>     
>>> postreset:SerialICE-hlp: outl 00e8 <= 496e6974 <=== this one kills serialice
>>>       
>> Init
>>     
>
> so weird. Where's it going?
>   

Management console on LPC? TPM?
"Init" could reenable/reinitialize the management console or cause the
management console to issue a reset command to the CPU and then act as
LPC master, presenting a totally different firmware to the CPU. That
would mean all serialice logs until then are just misdirection (but then
again, this is not a gaming console and such tricks are not that likely).

Of course, you could be hitting something entirely different: If the
management console starts reading commands or data from flash after the
"Init" command, it may fail to find anything useful there (after all,
only serialice is in that ROM) and simply go nuts. What happens if you
use a ROM with original size and have serialice at the end and the old
ROM contents everywhere else at the original address? (Pick old ROM,
overwrite the end with serialice, reflash). This could change behaviour
quite a bit. Of course, hooking up a LPC/FWH bus analyzer might help you
find out if there are any accesses not caused by serialice.


Regards,
Carl-Daniel

-- 
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