[LinuxBIOS] How to ID flash chip type from software?

[Ronald G Minnich]

Richard Smith wrote:
> On 2/27/06, Anton Borisov <a.borisov at tesv.tmb.ru> wrote:
> 
>>On Sun, 26 Feb 2006 16:55:54 +0100
>>Peter Stuge <stuge-linuxbios at cdy.org> wrote:
>>
>>
>>>Peel the shiny sticker off the chip if there is one and copy the chip
>>>manufacturer name and model number to the list if you don't recognize
>>>them.
>>
>>        There is no shiny sticker. It has a soldered chip. SST49LF004B.
> 
> 
> According to the datasheet  I got from here:
> 
> http://www.sst.com/products.xhtml/serial_flash/49/SST49LF004B
> 
> The Mfg ID of that part is a 0xBF not 0xDF.


Right. I bet if he dumps the top 256KB of memory (fffc0000 -ffffffff) he 
will see df is the first byte of the bios. The writes to the part, which 
you need to do for ID purposes, are not happening. They are disabled by 
some external hardware. Vendors do this all the time --- hookup up a 
GPIO to an and or or gate and don't tell anyone.

ron