fix MMCM parameter discovery - #210
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quetric merged 1 commit intoSep 1, 2026
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clock_driver_wait_for_lock() read the lock bit from offset 0x33C, which is not the status register. 0x33C is the second word of the CLKOUT0 leaf register pair, holding the high-time count in both of its low bytes, so the predicate tested bit 0 of the output divider's high-time count rather than PLL lock. The status register is at offset 0x04 and reports lock in bit 0, as the upstream Linux clocking wizard driver does. The consequence was that candidate selection rejected any (M, D, O) tuple whose high-time count was even, after stalling for the full 200 ms lock timeout. For a 365 MHz request this discarded the best-ranked candidate and settled on one producing a different VCO frequency; for requests where every candidate has an even high-time count it failed outright. Requests that happened to work, such as 200 MHz, did so only because the first candidate had an odd count. Read the status register instead, both when waiting for lock and when dumping wizard state for diagnostics. The state dump also carried its own copy of the leaf offset computation that still had the off-by-three error corrected in #210; call the shared helper. Fixes #206
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Improve MMCM parameter read-back and setting. More verbose logging of MMCM related activity in VRTD. Fixed #206