ot_flash: Fix bugs in reading keymgr secrets & improve trace
#225
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This wasn't causing any major problems (accidentally reading too many words from flash when reading keymgr seeds, but the right number of bytes were copied out when sending to the keymgr), but should be fixed regardless. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
rivos-eblot
requested changes
Oct 9, 2025
It turns out I completely misunderstood how `ot_fifo32_pop_buf` worked and had mistakenly conflated it with the current `fifo8_pop_buf` function which has a different signature. Correctly read out the flash secret by repeatedly popping the correct number of words out of the FIFO instead. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
I would have likely caught the previous bugs if I had properly traced the seed like the TODO suggests. Add the ability to dump the entire seed in the trace to make it easier to catch issues involving flash secrets in the future. Signed-off-by: Alex Jones <alex.jones@lowrisc.org>
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jwnrt
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Oct 9, 2025
rivos-eblot
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Oct 9, 2025
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See the commit messages. This PR fixes a couple of bugs in the flash controller related to reading keymgr secrets and improves the trace to help catch similar bugs in the future. This bug was causing garbage seeds to be read from flash, which was the reason we previously weren't getting the keymgr errors for unprovisioned flash as suggested by #220.