353 TODO

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TODO list for 353 cameras


NAND Flash

Flash memory on the 10353 board is larger than the SDRAM - on all previous models it was opposite. So it is not possible to have the flash image to be downloaded to the RAM as we did before.

At the same time 128MB is much larger than needed for the camera software (even with the sources and circuit diagrams that we always include according to our

/* source inside */


And - we have to handle bad blocks that just happen in NAND flash. When the system is running JFFS2+MTD will take care of the matter, but we need to address it while installing the initial image(s) while Linux is not loaded.

I believe we need to implement the following code:

  • store original bad block info (provided in each chip by the manufacturer) in the database for each camera built. That will help to restore the bad block table if accidentally erased by our developers or users;
  • Make several partitions (like boot, root and home), and include the absolute minimum it the initial image;
  • Decide on the bad block handling for the compressed kernel and initial programs (skipping? replacing) and implement it in the loader and network boot code;
  • The partition size for the compressed kernel image + minimal software can be fixed at some absolute value and include a couple spare blocks for bad block replacement. That will allow overwriting the kernel without changing other partitions;
  • Other partition(s) should be formatted (JFFS2) and the full software installed when the Linux kernel plus minimal software is running - probably camera should do it by itself downloading information from the server