[coreboot] r3393 - trunk/util/flashrom

[Stefan Reinauer]

Carl-Daniel Hailfinger wrote:
>> I don't think it makes much sense to differentiate between 29* types,
>> lpc and fwh:
>> The physical bus looks exactly the same from a software perspective;
>> until after you scanned the bus and know which category the chip you
>> found belongs to. And then the data is not exactly interesting anymore.
>>   
>>     
>
> Differentiating between LPC/FWH is important for the unlock procedure of
> some chips.
> Keeping the 29* parallel flash chips in a separate category fixes the
> AMIC chip confusion by 29EE probing.
>   
Ok, so make a suggestion how to determine the difference without probing
for the chips themselfes and we can discuss that.

> I meant bus/address pairs where appropriate. There can be only one chip
> per bus/address pair.
>   
There can even only be one chip per address, as those are physical cpu
addresses. The bus is not relevant here for any known design of flash
device.

>> But, I suggest we consider multiple flash busses once we see that happen
>> in the real world. At least the ICH is always strapped to either FWH
>> _or_ SPI.
>>     
>
> Except if you have a Kontron board (for which multiple flash chip
> support was written in the first place).
>   

Ok, I just checked the mail traffic on that one.  How do the bios straps
look on those systems?

Is there any method of finding out whether there is something on the SPI
bus physically?

Some systems seem to hang when probing the spi bus without devices
attached to it. Which is the origin of this discussion.




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