> > > Hi Bryan > > > > > > It would be good to explain what is wrong with the current code, > > > which allows you to select between the OTP and the EEPROM at write > time. > > > > Hi Andrew, > > > > The current code does not allow OTP read access. > > Plus the current code places unreasonable restrictions on OTP write > operations. > > Such as requiring offset == 0, length == 512, > > and data[0] == 0xF3, which is the signature used to indicate the first > > OTP > block is valid. > > However if the user wanted to use the second block, then data[0] should > be 0xF7, > > And data should start at offset 513. > > Also if you want to permanently invalidate the OTP then data[0] should > be 0xFF. > > This patch allows the user the program OTP with any offset, length and > data. > > And read access is necessary to confirm what is currently in the OTP. > > > > Would you like me to submit a new patch containing this information? > > Hi Bryan > > Yes, please indicate why the patch is needed.
OK > > > > Is the EEPROM mandatory? Could there be designs without an EEPROM? > > > When setting the private flag here, should you probe to see if there > > > actually is an EEPROM and return -ENODEV if it is missing. > > > > EEPROM is not mandatory. If EEPROM is not attached or contains invalid > > data, the lan743x will attempt to load configuration from on chip OTP > memory. > > > > To be honest, I'm not sure how to do a EEPROM probe with out doing a > > Write and read back test. And it is not recommended to do that due to > > limited write cycles which cause EEPROM damage. > > > > The current code does not do an EEPROM probe, so I don't see why the > > new code should. And we assume that the user can diagnose EEPROM > > presence using existing read/write operations. > > I would also put some text in the commit message to it is possible to swap to > the EEPROM using the private setting, even when the EEPROM is not > present. The failure will only happen later. With the current code, the > failure > is going to happen immediately. OK, I'll submit a new patch soon.
