[flashrom] [RFC, PATCH] Add read support for the Spansion S25FL129P flash chip

[Antonio Ospite]

On Thu, 27 Sep 2012 05:09:05 +0200
Stefan Tauner <stefan.tauner at student.tuwien.ac.at> wrote:

> On Wed, 26 Sep 2012 13:50:54 +0200
> Antonio Ospite <ospite at studenti.unina.it> wrote:
> 
> > http://www.spansion.com/Support/Datasheets/S25FL129P_00.pdf
> > http://www.spansion.com/Support/Application%20Notes/S25FL129P_Prog_Guide_AN.pdf
> > 
> > Signed-off-by: Antonio Ospite <ospite at studenti.unina.it>

[...]
> i pity you, because that chip is not one of the more simple ones, but
> your patch seems to be ok on the first look. :) i need to look more
> closely at it, after we fix the probing...
>

My doubts were mostly about the block_erasers.

> > Moreover from the Datasheet (Table 9.2, page 34) I see that this chip comes in
> > two variants, one with 64K sectors and one with 256KB sectors,
> 
> that's quite a problem. while flashrom would not care too much, because
> it just tries all erase functions available in cases of failure, we
> usually do not merge such patches without being able to differentiate
> between the chips (which sometimes requires to get very creative :).
> 
> > and some
> > "Extended Device Identification" is used to identify the right variant,
> > I don't know if flashrom supports reading such information.
> 
> in your case it is easier as you have found out already. flashrom does
> not support EDI yet, but i am working on it. because flashrom supports
> some very funky SPI masters (which have very annoying limitations on the
> number of bytes to read and write in a single transaction) it is not
> completely trivial to add this though. after that we can add the two(!)
> chips from your patch (and maybe there exist other similar chips of
> the same family with different capacities... have you looked for them?).
>

Stefan please CC me when you get to send EDI related patches, I am
subscribed to the list for now but you never know.
 
> > I didn't feel like testing erase/write either as the connection to the chip
> > was/is quite unreliable, I just needed to get a rootfs off from it once (it's
> > some embedded router). If anyone can suggest some really cheap place where to
> > get test clips or probes in Italy (or even better feels like donating some),
> > I might risk testing erase/write after we solve the issue about the chip
> > variant.
> 

[...]
> for the SOIC16 the Pomona model number is 5252, tme does not seem to
> have it but distrelec does and probably also any other electronics
> reseller (mouser, rs, farnell etc).
>

I picked up a Pomona 5252 from it.mouser.com along with other stuff I
might need so to reach the free-shipment quota.

> PS: i have committed some ft2232_spi changes lately (r1608 - r1610). i
> would be glad if you would upgrade and report if you have any issues
> with them.
>

I'll let you know once I have the test clip.

JFYI for the previous read test I used a 16pin DIP socket carrier to
which I deformed the pins to match the SOIC spacing, that worked
because the SOIC pins I was targeting were quite sparse, but the
connection is not very firm as you can guess and it takes time to
align the pins at every insertion.

Regards,
   Antonio

-- 
Antonio Ospite
http://ao2.it

A: Because it messes up the order in which people normally read text.
   See http://en.wikipedia.org/wiki/Posting_style
Q: Why is top-posting such a bad thing?