Three layered root causes kept ADV.wmv from playing. This lands the first
three fixes: the intro video now decodes end-to-end and uploads its YUV
planes. The on-screen composite still needs a multi-texture render path
(root #3, tracked separately — the shader interpreter binds one texture slot
but the YUV->RGB pass samples three).
1. Clock scale (xenia-kernel/state.rs): INSTRUCTIONS_PER_MS 10_000 -> 1_000_000.
KeTimeStampBundle tick_count = global_clock / INSTRUCTIONS_PER_MS. At 10_000
(~10 MIPS; global_clock further inflated ~58x by the serialized scheduler
summing busy-spin) the movie handler's 2000 ms software-decode deadline
(sub_821B4968 @0x821b68c0) tripped on a legitimate ~20M-instruction
720p-YUV420 decode and aborted playback (canary never enters that wait
loop). 1_000_000 sits in the validated [~600k, ~2.77M] window that fits
both the movie (decode <=2000 ms) and boot (the worker-hub +66 ms gate
still elapses before the movie, ~66M instr). XENIA_INSTR_PER_MS overrides.
2. Scheduler fairness (xenia-cpu/scheduler.rs): pick_runnable's equal-priority
tiebreak now prefers the incumbent (running_idx) so decrement_quantum's
quantum rotation sticks. Previously each round re-picked the lowest index,
so co-located equal-priority threads never alternated and the movie's demux
feeder (tid24, co-located on hw=1) starved until the STARVE_LIMIT=4096
backstop -- the decode ring never refilled. Priority preemption unaffected.
XENIA_INCUMBENT_PICK=0 rolls back.
3. k_8 texture decode (xenia-gpu/texture_cache.rs + xenia-ui/texture_cache_host.rs):
the video uploads its YUV420 planes as linear k_8 textures (Y 1280x720,
U/V 640x360); with no k_8 decoder ensure_cached rejected them and the frames
never reached the GPU. Adds decode_k8 (1 byte/texel expanded to Rgba8Unorm)
+ the host Rgba8Unorm mapping.
Read-only diagnostic probe knobs used to find these remain uncommitted in the
working tree. Boot goldens re-baselined in a follow-up commit (the clock change
intentionally moves the digest; see tests/golden/README.md).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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