Hello Anastasia,
Many thanks for your quick reply!
This needs to be designed... for example, what are the possible sizes
of those smaller EEPROMs? can that be any size, or only a few standard options (like 256 and 512 bytes)?
Microchip has 128, 192, 256 and 512 byte EEPROMs (below 1024 bytes).
They do offer a DFP (bunch of XML device descriptors) from which the flash descriptors could be generated. -- Miklos
Anastasia Klimchuk aklm@chromium.org ezt írta (időpont: 2024. aug. 15., Cs, 14:50):
Hello Miklos,
I remember this, I was in a (somewhat) similar situation when I was writing unit tests. The total_size is in kilobytes and so the smallest size would be 1 kilobyte. While I only needed 16 bytes for test scenarios. The workaround for unit tests is to put 1 as total_size, then have 1024 bytes as a "total memory" but only really care about the first 16 bytes.
I think you can try something in that direction. Something like, what if you put 1 as total_size (not 0), and then create a layout with one region of 512 bytes (or how much is real-total-size), and only operate on this region. Do you have a work in progress code that you could upload as a WIP patch? It might be easier to talk over the code.
Both layout boundaries, and erase block sizes are measured in bytes, so they can be defined in an actual size.
Is supporting smaller EEPROMs considered a feature what could be merged
at some point
I think yes, why not merge a useful feature. If we figure out the working solution :)
This needs to be designed... for example, what are the possible sizes of those smaller EEPROMs? can that be any size, or only a few standard options (like 256 and 512 bytes)?
Maybe it can be a feature flag (FEATURE_MICRO256B or something like that), and then with this feature flag layout with 256 bytes region can be silently created.
On Thu, Aug 15, 2024 at 12:10 AM Miklós Márton martonmiklosqdev@gmail.com wrote:
Hello all,
I tried to add support for some Microchip serial EEPROMs to being able
to program them with an STLinkV3. I ran into problems with the smaller EEPROMs for e.g. 25LC040 which is only a 4Kbit device.
The total_size in the flashchip structure is an unsigned int so I could
only enter 0 as total size.
In this case the flashrom shows the following message to me: ERROR: Flash chip 25C040 erase function 0 region walking resulted in
0x000200 bytes total, expected 0x000000 bytes. Please report a bug at flashrom@flashrom.org
ERROR: Flash chip 25C040 erase function 0 is not in order. Please report
a bug at flashrom@flashrom.org
Is there any recommendations how to overcome on this? Is supporting smaller EEPROMs considered a feature what could be merged
at some point, or the flashrom is going to focus purely on flash memories?
-- Miklos _______________________________________________ flashrom mailing list -- flashrom@flashrom.org To unsubscribe send an email to flashrom-leave@flashrom.org
-- Anastasia.