4cfe0b470f8488331d5b28ea7716013c5ef277da
18 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 claude-noether
|
a43296c1ed |
daemon: bounds-check pack_* functions against CAPTURE plane size
The three NV12/P010 pack functions (pack_nv12_single_to_plane, pack_nv12_to_planes, pack_p010_to_plane) wrote into the V4L2 client's CAPTURE dmabuf without checking that the mapped size covers the frame libavcodec just decoded. Crash scenario: YouTube DASH stepping resolution mid-stream (e.g. 480p -> 720p when bandwidth improves) — libva is supposed to handle the V4L2_EVENT_SOURCE_CHANGE with STREAMOFF / S_FMT / REQBUFS, but in practice a stale CAPTURE request with the old buffer size sometimes slips through carrying the new (larger) frame. The chroma-interleave inner loop walks past the mapping boundary and the daemon takes SIGSEGV mid-frame, which in turn leaves V4L2 clients hanging in vb2_core_dqbuf — see the followup ticket on the D-state symptom. Fix: compute required = y_size + uv_size against planes->size[N] BEFORE any write. On mismatch, log_warn with both sizes and the frame dimensions, and return -EOVERFLOW. The caller (process_decode_request loop) already handles a negative pack return with a log_warn and proceeds without aborting the decode — the kernel still gets the response with metadata-only and the V4L2 client sees a frame whose pixels are stale but whose buffer-done event fires normally. The next SOURCE_CHANGE the client processes resyncs the buffer size. All three pack paths get the same bounds-check; the comment on pack_nv12_single is the canonical explanation, the other two reference it. Verified: builds clean against trixie aarch64; no behavioural change on the happy path (the bounds check is a single size compare; on a correctly-sized CAPTURE buffer it's a 1-cycle pass). Closes daedalus-v4l2 task #145 (daemon SEGV in pack_nv12_single on resolution change). |
||
 marfrit
|
3e4e6e8eae |
daemon: filter tiny pause-time bitstreams (closes #17)
libva-v4l2-request-fourier flushes a stub packet into the V4L2
OUTPUT_MPLANE queue at playback-pause boundaries. The payload is
shorter than any parseable H.264 NAL (3-byte start code + 1-byte
NAL header = 4 bytes minimum); avcodec_send_packet returns
AVERROR_INVALIDDATA (-1094995529), which propagated to the kernel
as a decode failure. Firefox then marked H.264-via-VAAPI as
broken for the session and routed every subsequent frame to
libmozavcodec SW — pause never recovered to HW.
At the REQ_DECODE entry in chardev_client.c::handle_req_decode,
short-circuit any bitstream below the minimum-parseable threshold:
log INFO, skip daedalus_decoder_run_request, and reply RESP_FRAME
with status=DAEDALUS_DECODE_NO_FRAME so libva's V4L2 surface pool
stays healthy and Firefox doesn't see a failure.
Repro: Pi CM5 trixie, daedalus-v4l2 0.1.0+r41 + ffmpeg-v4l2-
request-fourier 2:8.1+rfourier+gb57fbbe-9, Firefox YouTube avc1.
Play → daemon decodes at ~46 fps. Pause ≥ 1s. Resume → daemon
silent; sudo journalctl -u daedalus-v4l2 --since '10s' | grep -c
'decoder: OK' = 0. Last entry before silence:
REQ_DECODE cookie=N codec=3 bitstream=3 bytes ...
[h264 @ ...] no frame!
[ERR] decoder: avcodec_send_packet failed: -1094995529
After this fix the 3-byte sentinel logs as 'tiny bitstream 3
bytes — dropping as no-op' and the libavcodec context is
untouched; the next real REQ_DECODE proceeds normally.
Scope NOT covered (intentionally deferred):
- A more general "tolerate AVERROR_INVALIDDATA mid-stream" path.
Worth doing later but masks unrelated bugs.
- Investigating WHY libva sends the 3-byte sentinel on pause.
Likely an upstream libva-v4l2-request-fourier issue; tracked
separately if this filter is not enough.
Wire protocol unchanged. No DAEDALUS_PROTO_VERSION bump.
|
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|
claude-noether
|
514da29a73 |
daemon: dlopen Kwiboo fork's libavcodec.so.62 / libavformat.so.62 / libavutil.so.60
Switch the daemon's runtime dlopen targets from Debian-stock soname 61/61/59 (FFmpeg 7.1.3) to the Kwiboo fourier fork's soname 62/62/60 (FFmpeg 8.1) installed at the /opt/fourier prefix. Why --- The substitution arc tracked at daedalus-v4l2#11 needs daedalus- fourier kernel calls woven into libavcodec's H264DSPContext NEON init (replacing ff_h264_idct_add_neon etc. with thunks calling daedalus_recipe_dispatch_h264_*). We do that via patches in the ffmpeg-v4l2-request-fourier package source — which we own, in marfrit-packages, alongside the existing libudev-bypass and nv15-to-p010 patches. But that package builds the Kwiboo fork at soname 62 / /opt/fourier. The daemon currently dlopens soname 61 (Debian-stock + a separately-built +fourier2 patch that isn't in marfrit-packages' source tree), so substitution patches there wouldn't reach the daemon. Switching to soname 62 routes the daemon through the package we control — first step toward landing daedalus-fourier kernel substitution into the production decode path. Compat ------ - /opt/fourier libs are already on every host running the daemon (hard build-dep of ffmpeg-v4l2-request-fourier). Firefox-fourier and mpv-fourier already dlopen them via the same path. - /etc/ld.so.conf.d/fourier.conf entry resolves the new sonames from /opt/fourier/lib via the ld cache; dlopen-by-soname works without LD_LIBRARY_PATH wrappers. - Build-side: daemon's pkg_check_modules picks up libav*.pc from /opt/fourier/lib/pkgconfig when PKG_CONFIG_PATH includes that directory (build-deb.sh follow-up will set it). - API surface unchanged: avcodec_send_packet / receive_frame / AVCodecContext flags / AVFrame fields are all stable between FFmpeg 7.1 and 8.1. Verified clean cross-compile on hertz. Wire protocol unchanged. No kmod bump. Next step (follow-up PRs) ------------------------- 1. ffmpeg-v4l2-request-fourier patch: add 0003-daedalus-fourier- substitute-h264-idct4.patch that replaces ff_h264_idct_add_neon in libavcodec/aarch64/h264dsp_init_aarch64.c with a thunk calling daedalus_recipe_dispatch_h264_idct4. 2. Repeat for IDCT 8×8, deblock luma-v, qpel mc20 (one kernel per PR for reviewability; bench delta + decode_us delta documented per substitution). 3. marfrit-packages bump to pick up the new daemon + the substituted fourier package. |
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|
claude-noether
|
814b74d0bb |
daemon: per-frame decode_us + periodic stats summary (#11 step 1)
Establishes observable baseline metrics before any daedalus-fourier
kernel substitution lands. Step 1 of the daemon-rewrite arc tracked
at daedalus-v4l2#11.
Changes
-------
- Per-frame `decoder: OK ...` log line now carries decode_us=N (the
send_packet + receive_frame wall-clock cost in microseconds —
exclusively the libavcodec round-trip, not the bitstream pack /
SPS-PPS synth / pack-to-planes work).
- New "decoder stats" summary line every DAEDALUS_STATS_EVERY (60)
decoded frames, reporting: codec, frame count, window seconds,
fps, avg decode_us, MBs/s throughput, bytes/MB bitrate.
Sample
------
decoder stats: codec=h264 frames=300 window=12.32s fps=24.35
avg_decode_us=4216.4 mbs_per_s=87643 bs_b_per_mb=1.56
What this tells us
------------------
Steady-state on higgs (Pi CM5) decoding bbb_720p_h264.mp4:
~4 ms decode_us, ~90 K MBs/s, well under the daedalus-fourier
NEON kernel ceilings (IDCT 4×4 @ 175 Mblocks/s, deblock @ 92 Medges/s,
qpel mc20 @ 131 Mblocks/s — all 100-1000× over our actual workload).
Means the 4 ms/frame is mostly libavcodec's CABAC + MV prediction +
intra prediction overhead, NOT the pixel-math primitives.
Substituting a single primitive would shave only a small slice of
the 4 ms. Useful as guidance for the upcoming substitution work —
we'll pick the primitive with the largest cycle cost relative to
the alternative, and measure CPU saved per substitution.
No behaviour change: counters are static + unsynchronised (the
chardev event loop is single-threaded); reset when codec_id changes.
clock_gettime(CLOCK_MONOTONIC) for timing.
|
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marfrit
|
77e14e5a19 |
Merge pull request 'daemon: link daedalus-fourier + log substrate availability at startup' (#13) from noether/daemon-link-daedalus-fourier into main
Reviewed-on: #13 |
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|
claude-noether
|
88b2ebfaa9 |
daemon: link daedalus-fourier + log substrate availability at startup
First incremental step toward H.264 daemon-rewrite (daedalus-v4l2#11):
make the daedalus-fourier kernel library available to the daemon
process so subsequent patches can substitute its primitives
(IDCT 4×4, IDCT 8×8, luma vertical deblock, etc.) for libavcodec's
per-MB pixel math.
This patch does NOT yet dispatch any kernels. It only:
- Adds `pkg_check_modules(DAEDALUS_FOURIER REQUIRED daedalus-fourier)`
to the daemon's CMakeLists, with explicit link ordering
(libdaedalus_core.a must precede -lvulkan because the static
archive references vulkan symbols and the linker resolves
left-to-right). We bypass IMPORTED_TARGET because pkg-config's
Requires.private chain leaves CMake's dependency graph reordering
the archive after -lvulkan, breaking the static link.
- Calls daedalus_ctx_create_no_qpu() at daemon startup, logs the
substrate-availability line, destroys the context at exit.
no_qpu mode skips V3D Vulkan probe — proves linkage works
without depending on shader-path resolution (which is a
separate piece of work, since v3d_runner currently loads
.spv files from cwd-relative paths and consumer would need
a search path override).
Sample journal line:
[2026-05-21 17:59:35.271 INFO] daedalus-fourier: linked, ctx alive
(no_qpu mode; has_qpu=0)
Build-test verified on hertz (Pi 5 dev host) against an installed
copy of daedalus-fourier r35+gd87239d (from marfrit/daedalus-fourier
PR #1). Binary links cleanly, --help prints, daemon mode opens
chardev (fails predictably on hertz which has no daedalus_v4l2
kmod; on higgs this is the existing working path).
Follow-up patches per daedalus-v4l2#11:
1. Instrument the existing libavcodec decode path to count
per-frame IDCT blocks / deblock edges / MC tiles so we have
a baseline of what work the daemon dispatches for a typical
YouTube H.264 stream.
2. Substitute daedalus-fourier kernels one at a time, measuring
CPU saved per substitution.
3. Wire shader path resolution into daedalus_ctx_create() for
the QPU substrate (V3D opportunistic helper paths).
Wire protocol unchanged. DAEDALUS_PROTO_VERSION stays at 0.
|
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claude-noether
|
234a103084 |
daemon: AV_CODEC_FLAG_LOW_DELAY for H.264 — fix display-reorder breaking V4L2 1:1
Force libavcodec's H.264 decoder to emit frames in DECODE order (one frame per send_packet, no internal display-order reorder queue). Single-line addition: ctx->flags |= AV_CODEC_FLAG_LOW_DELAY before avcodec_open2, gated on codec_id == DAEDALUS_CODEC_H264. Closes daedalus-v4l2#11 part (2). Background ---------- PR #7's "parking design" approach to the H.264 display-reorder problem broke libva-v4l2-request-fourier's 1:1 CAPTURE-completion contract (see #9 + #10). After the revert, the visible "2 1 4 3" pair-swap regressed and the only path forward was to align the daemon's output ordering with what V4L2 stateless clients expect: **decode order, one CAPTURE buffer per OUTPUT slice, with display reorder pushed upstream to ffmpeg-vaapi's per-VAAPI-surface POC logic** (which it already does correctly for every real H.264 hardware decoder via VAPictureParameterBufferH264). How LOW_DELAY does this ----------------------- Inside libavcodec/h264dec.c, the flag sets h->low_delay = 1. h264_select_output_frame (h264_picture.c) emits the just-decoded picture immediately instead of routing through the display-order DPB output queue. DPB management for reference frames (short_ref / long_ref) is unaffected — B-frame decoding correctness is preserved; only the output buffering is bypassed. Skipped for VP9 / AV1 — those codecs don't reorder internally, so the flag would be a no-op but adds no value. Verified -------- On higgs (Pi CM5, 6.18.29+rpt-rpi-2712), test daemon hot-swapped into /usr/bin/daedalus_v4l2_daemon, mpv --hwdec=vaapi-copy --frames=300 against bbb_720p_h264.mp4: 311 REQ_DECODEs received, 308 successful "decoder: OK" responses (99.04% steady-state delivery — 3 lost at GOP boundaries, no compounding drift). mpv plays to its --frames cap and exits cleanly with "End of file". No "Unable to dequeue buffer", no "Failed to end picture decode", no "AVHWFramesContext: Failed to sync surface" — all the failures from #9 are gone. Builds clean against ffmpeg-v4l2-request-fourier libavcodec. |
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marfrit
|
714d781d22 |
Revert "Merge pull request 'kernel + daemon: H.264 B-frame display reorder fix (closes #6)' (#7) from noether/kernel-daemon-h264-reorder-fix into main"
This reverts commit |
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|
claude-noether
|
15fc2aba14 |
kernel + daemon: H.264 B-frame display reorder fix (issue #6)
H.264 streams with B-frames showed visibly pair-swapped output in
mpv / Firefox playback through the libva → daedalus_v4l2 path —
"frames went 2 1 4 3 6 5 instead of 1 2 3 4 5 6". Reproduced in mpv
with --hwdec=vaapi-copy at 720p (bypassing Firefox's compositor),
confirming the bug was in this daemon pipeline, not downstream.
Root cause
----------
libavcodec's H.264 decoder internally reorders output to DISPLAY
order before returning from avcodec_receive_frame. The daemon
previously called send_packet → receive_frame ONCE per REQ_DECODE
and shipped the resulting pixels in a RESP_FRAME tagged with the
SAME cookie. For B-frames this is wrong: the frame returned from
receive_frame may belong to an EARLIER bitstream (libavcodec held
it for display-order release). Cookie N's CAPTURE buffer therefore
got cookie N-2's pixels, while cookie N-2's CAPTURE buffer got
silently marked VB2_BUF_STATE_ERROR (the daemon returned
DAEDALUS_DECODE_NO_FRAME for the cookie whose pixels were held).
Fix shape
---------
Decouple kernel cookie identity (decode-order routing) from
libavcodec's display-ordered output. Wire-protocol changes:
REQ_DECODE + __u64 src_pts (= src_buf->vb2_buf.timestamp)
RESP_FRAME + __u32 flags (HAS_PIXELS | SRC_CONSUMED)
+ __u64 output_src_pts (= frame->pts on drain)
PROTO_VERSION bumped 0 → 1. Lock-step rebuild required.
Kernel
------
device_run now mirrors src_buf->vb2_buf.timestamp into req->src_pts
before sending REQ_DECODE, and stores it on the inflight item so
the completion path can stamp dst_buf.timestamp explicitly when
src/dst lifecycles decouple (V4L2_BUF_FLAG_TIMESTAMP_COPY's auto-
pairing no longer applies).
daedalus_complete_resp_frame splits into:
HAS_PIXELS: pack pixels into THIS cookie's CAPTURE buffer,
stamp dst timestamp from inflight->src_pts,
v4l2_m2m_buf_done(dst, DONE/ERROR).
No job_finish here.
SRC_CONSUMED: release the bound media_request, run
v4l2_m2m_buf_done(src) + v4l2_m2m_job_finish so
the scheduler can dispatch the next REQ. dst_buf
may still be parked at this point.
Inflight entry is removed and freed only when BOTH src_buf and
dst_buf have been cleared. Combined HAS_PIXELS|SRC_CONSUMED RESPs
(steady-state VP9/AV1 with no reorder lag) collapse to the prior
1:1 behaviour for free.
Daemon
------
daedalus_decoder_run_request split into three primitives:
daedalus_decoder_submit — set pkt->pts = req->src_pts,
avcodec_send_packet.
daedalus_decoder_drain_one — avcodec_receive_frame, populate
resp meta + output_src_pts (= the
frame's pts, carried back from
the bitstream that produced it).
daedalus_decoder_pack_current — pack current AVFrame into the
caller-mapped CAPTURE planes.
chardev_client maintains a small (src_pts → cookie, cached_req)
table indexed linearly (≤64 entries; bounded by V4L2 client buffer
pool depth). On each REQ_DECODE:
1. Register (src_pts → cookie) in the table.
2. submit().
3. Drain loop: for each frame returned, look up its owner cookie
via pending_lookup(frame->pts), GET_DMABUF for THAT cookie,
pack pixels, emit RESP_FRAME(owner_cookie, HAS_PIXELS,
output_src_pts=frame->pts). Combine with SRC_CONSUMED when
owner_cookie equals the current REQ's cookie.
4. If the current REQ's cookie wasn't drained inside the loop
(libavcodec held the frame), emit a standalone SRC_CONSUMED
RESP so the kernel runs job_finish + dispatches the next REQ;
dst_buf for this cookie stays parked until a future drain
produces its pixels.
VP9 / AV1 paths are unchanged in behaviour: one frame per REQ,
HAS_PIXELS|SRC_CONSUMED in one combined RESP.
Verified
--------
Builds clean cross-compiled on higgs against 6.18.29+rpt-rpi-2712
(Pi CM5). Frame-size warning in device_run is pre-existing
(unchanged by this commit).
|
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|
marfrit
|
29f16ece13 |
kernel: bind request controls to p_cur before reading them
device_run was reading ctrl->p_cur.p_h264_* directly, but v4l2-m2m's request scheduler does NOT auto-bind the in-flight media_request's control values to the ctrl handler's p_cur slots — drivers have to call v4l2_ctrl_request_setup() explicitly. cedrus / rkvdec / hantro all do this in their device_run; daedalus didn't. Result: daedalus_collect_h264_meta() read stale or default values (whatever the prior request had left in p_cur, or v4l2_ctrl_new_custom initial state if no prior request had completed) instead of the S_EXT_CTRLS V4L2_CTRL_WHICH_REQUEST_VAL values libva-v4l2-request- fourier had just sent for THIS frame. The mismatch was a smoking gun on higgs after libva PR #9 / packages PR #52 landed an instrumentation log at h264_set_controls entry: libva boundary (sent to kernel): VAProfile=13 seq_fields=0x00032051 pic_fields=0x00000500 num_ref_frames=1 daedalus daemon (read from kernel p_cur): prof=100 level=41 ref_frames=0 flags=0x10 pps_flags=0x0 After calling v4l2_ctrl_request_setup() at the top of device_run: daedalus daemon (read from kernel p_cur): prof=66 level=11 ref_frames=1 poc_type=2 flags=0x50 pps_flags=0x88 — matches what libva sent, matches the bitstream's actual SPS. End-to-end test on higgs with libva-v4l2-request-fourier 1.0.0+r382 +gc1bb444 (after-fix-3-and-fix-4-instrumentation) + this kernel patch: $ LIBVA_DRIVER_NAME=v4l2_request ffmpeg -hwaccel vaapi \ -hwaccel_device /dev/dri/renderD128 -i h264_test.mp4 \ -frames:v 1 -f null - ... rc=0 daemon journal: zero "error while decoding MB" lines, zero "reference frames exceeds max" lines. Per-frame fnv1a hashes differ (0xf1c515aa, 0x16e915e8, 0x16bd16cc, ...) instead of the constant 0x6a6a05c5 "give-up-and-zero" hash from before — libavcodec is actually decoding real pixel content from each P-frame. Pair note: the daemon side already calls v4l2_ctrl_request_complete in daedalus_complete_resp_frame (line 834) — this commit pairs the setup half with that completion half. The daemon side change (decoder.c) is a small log-level promotion: the per-frame "h264 SPS/PPS prepended ..." trace went from log_debug to log_info so the journal shows what's being shipped into libavcodec without needing a daemon rebuild with --debug. Matches the libva- side h264_set_controls instrumentation that landed in libva PR #9. Closes part of issue libva-v4l2-request-fourier#8 — the SPS/PPS field-value gap. Profile/level still come from libva's session- derived hardcoded values (h264_profile_to_idc + h264_derive_level_ idc) which is sufficient for libavcodec to accept the synthesised NAL unit; a true stream-parsed profile/level would need SPS-NAL parsing in libva — separate operator-design call. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com> |
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marfrit
|
8c1d9960c4 |
DAEMON-PPS: synthesise H.264 SPS/PPS NAL units from V4L2 controls
libva-v4l2-request-fourier (and any V4L2-stateless-API consumer)
passes H.264 SPS/PPS as separate V4L2_CID_STATELESS_H264_{SPS,PPS}
controls; only the slice NAL goes into the OUTPUT buffer. This is
correct per the V4L2 stateless contract. But libavcodec — which
the daedalus daemon uses for actual decode (Option γ) — wants a
self-contained AnnexB stream including SPS+PPS before any slice.
Result on higgs: "non-existing PPS 0 referenced" + decode_slice_
header errors on every H.264 frame, even after LIBVA-1 and -2
routing correctly delivered the request to the daemon.
Fix splits across kernel + daemon, keeping the kernel module as a
thin transport and putting the actual NAL encoding in userspace:
include/daedalus_v4l2_proto.h:
Add struct daedalus_h264_meta (the four v4l2_ctrl_h264_*
structs the kernel collects) and DAEDALUS_REQ_FLAG_H264_META
(set in req.flags when the meta block is present between the
daedalus_req_decode prefix and the slice bitstream).
kernel/daedalus_v4l2_main.c:
Add daedalus_collect_h264_meta() — reads the H.264 ctrl values
from the bound media_request via v4l2_ctrl_find +
ctrl->p_cur.p_h264_*. device_run() calls it on H.264 codec_id,
copies the structs into the REQ_DECODE payload between the
prefix and bitstream, and sets the flag. Payload size is
bounds-checked against DAEDALUS_PROTO_MAX_PAYLOAD so an over-
sized slice + meta fails loud instead of truncating.
daemon/src/bitstream_writer.{c,h}:
New module — MSB-first bit packer with H.264 Exp-Golomb ue(v)
and se(v) coding + rbsp_trailing_bits alignment. Sticky
overflow flag so callers can verify the output buffer wasn't
truncated.
daemon/src/h264_nal_synth.{c,h}:
New module — turns v4l2_ctrl_h264_sps / v4l2_ctrl_h264_pps
into AnnexB-framed NAL units per ITU-T H.264 7.3.2.1 / 7.3.2.2.
Emits emulation prevention bytes (0x03 after every 00 00 in the
EBSP) and the 4-byte start code (0x00000001). Coverage matches
what V4L2 stateless surface gives us: VUI parameters and full
scaling matrices are NOT emitted (V4L2 doesn't carry them — the
seq_scaling_matrix_present_flag is set to 0 and libavcodec uses
flat defaults, which matches the de-facto behaviour of most
H.264 streams libva-v4l2-request drives).
daemon/src/decoder.c:
daedalus_decoder_run_request() now takes an optional
h264_meta parameter. For codec_id == H264 with meta != NULL,
synthesises SPS+PPS NAL units, allocates a combined
[SPS][PPS][slice] buffer (+ AV_INPUT_BUFFER_PADDING_SIZE), and
feeds that to avcodec_send_packet instead of the raw slice.
VP9/AV1 path unchanged (frames are self-contained). Cleanup
now goes through a unified `out:` label so the assembled
buffer is always freed on every exit (including the existing
decoder_open_codec / no-frame / receive_frame failure paths).
daemon/src/chardev_client.c:
handle_req_decode() peels off the optional meta block when the
flag is set, passes it through to the decoder, and updates
the payload-length consistency check (now allows for an extra
sizeof(daedalus_h264_meta) when the flag is on).
Build (boltzmann aarch64): clean compile of all daemon sources,
including bitstream_writer + h264_nal_synth + the refactored
decoder.c. Kernel module compile to be verified via DKMS rebuild
on higgs in the marfrit-packages bump that follows.
Test plan: with this commit + a marfrit-packages daedalus pin
bump, higgs's ffmpeg -hwaccel vaapi -i h264_test.mp4 should
produce a successful decode (vs. the previous "non-existing PPS 0
referenced" failure). The daemon log should show:
decoder: opened h264 context
decoder: h264 prepended SPS=NB PPS=MB slice=KB
decoder: OK 320x240 fmt=0 (yuv420p) fnv1a=0x...
VP9 / AV1 behaviour unchanged — they don't carry meta and the
existing per-frame self-describing path still applies.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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marfrit
|
0de0288dce |
Phase 8.10+8.11: libva consumer integration scaffold
Brings daedalus_v4l2 from "standalone test client" to "VAAPI-
discoverable decoder" by adding the surface formats and
media-controller plumbing that libva-v4l2-request-fourier
(sibling repo) requires.
libva-v4l2-request-fourier patches (pushed separately):
- b5b3acf: daedalus_v4l2 added to known_decoder_drivers
- 2146341: meson option gate
This commit (daedalus-v4l2 side, 3 production changes):
1. V4L2_PIX_FMT_NV12 (single-plane) on CAPTURE
- Added to daedalus_capture_formats[] alongside NV12M + P010
- daedalus_fill_capture_fmt handles num_planes=1 case
(sizeimage = W*H*3/2, bytesperline = W)
- daemon pack_nv12_single_to_plane: Y at base+0,
interleaved CbCr at base+(stride*H); same byte content
as NV12M two-plane, different layout
- Required because libva-v4l2-request-fourier's video.c
only knows non-multi-plane NV12 (it advertises
v4l2_mplane=true but uses the single-plane fourcc).
- Verified byte-exact via test_m2m_stream against
ffmpeg -pix_fmt nv12 reference (VP9 1080p 10 frames,
31 MB).
2. V4L2 Request API media ops
- daedalus_media_ops = { vb2_request_validate,
v4l2_m2m_request_queue } assigned to mdev.ops before
media_device_init.
- Without this, MEDIA_IOC_REQUEST_ALLOC returned
-ENOTTY and no VAAPI consumer could allocate a
media_request.
3. Stateless control registration via v4l2_ctrl_new_custom
- Switched from v4l2_ctrl_new_std_compound(NULL p_def)
to v4l2_ctrl_new_custom — pattern rkvdec/cedrus/
hantro use. Adds a no-op s_ctrl callback.
Verification (hertz, Pi 5, 6.12.75+rpt-rpi-2712):
LibVA trace through `ffmpeg -hwaccel vaapi`:
vaInitialize / Profiles / Entrypoints / CreateConfig /
QuerySurfaceAttributes / CreateSurfaces / CreateContext
(cap_pool: 24 slots, 1 plane each) / CreateBuffer
(slice + picture params) / MEDIA_IOC_REQUEST_ALLOC
— all succeed.
Standalone NV12 decode path:
test_m2m_stream vp9_1080_stream.ivf out.nv12 1920 1080 vp9 nv12
→ 10/10 frames, byte-exact vs ffmpeg -pix_fmt nv12
vainfo (via libva-v4l2-request-fourier with our driver):
7 VAProfile entries with VAEntrypointVLD
(H264 Main/High/CBaseline/MultiviewHigh/StereoHigh,
VP9Profile0, AV1Profile0)
What's NOT here (Phase 8.12):
The libva trace stops at VIDIOC_S_EXT_CTRLS returning
EINVAL when populating V4L2_CID_STATELESS_VP9_FRAME on
the request. The compound-control payload validation
against the kernel's expected struct shape rejects.
This isn't a "missing line" fix — it needs proper
stateless control plumbing (the SPS/PPS/SliceParams
get_dims, validate, default-value paths that in-tree
rkvdec/cedrus/hantro implement to satisfy v4l2-core's
std_validate). Documented as Phase 8.12 scope.
The shipped integration is itself a meaningful deliverable:
all the framework scaffolding is in place; the remaining
gap is well-characterised and bounded.
See docs/phase_8_10_11_closure.md for the full trace
analysis + next-phase plan.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
1ae9528e76 |
Phase 8.8: throughput baseline + multi-codec streams + HDR
Per the correctness-before-speed principle: measure before
optimising. Roadmap going in said "QPU dispatch substitution
to hit 30fps@1080p". Measurement on hertz shows the FFmpeg
software path already hits 65-88 fps@1080p across all three
codecs — QPU substitution would be premature optimisation.
So 8.8 ships what's actually useful:
1. Per-frame timing in test_m2m_stream.
2. Multi-frame AV1 + H.264 streams verified byte-exact at
1080p (closes the "VP9-only stream tests" gap from 8.7).
3. HDR / 10-bit via V4L2_PIX_FMT_P010 + daemon
pack_p010_to_plane.
Test harness (tools/test_m2m_stream.c):
- Per-frame µs timing via CLOCK_MONOTONIC; reports mean/p50/
p99/min/max + wall ms + fps.
- Annex-B H.264 parser: split on 3-/4-byte start codes,
accumulate NALs into access units (push on VCL NAL types
1 or 5). Without AU grouping FFmpeg rejects SPS/PPS-only
buffers as "no frame!".
- Format auto-detect (DKIF magic → IVF; else Annex-B).
- Optional 6th arg `[capture]`: nv12m | p010.
- CAPTURE mmap path generalised for num_planes==1 (P010).
Kernel (kernel/daedalus_v4l2_main.c):
- CAPTURE formats array {NV12M, P010}; enum_fmt walks it.
- daedalus_fill_capture_fmt takes a fourcc:
NV12M: 2 planes, W*H + W*H/2 bytes, bpl=W
P010: 1 plane, W*H*2 + W*H bytes, bpl=W*2
- try_fmt preserves caller fourcc when supported.
- daedalus_complete_resp_frame's dmabuf path now sets each
plane's payload to vb2_plane_size(vb,p) — generalises
cleanly across 1-plane (P010) and 2-plane (NV12M) layouts;
the daemon fully populates the plane so payload =
sizeimage.
Daemon (daemon/src/decoder.c):
- pack_p010_to_plane: YUV420P10LE → P010 single-plane.
10-bit samples shifted left by 6 to MSB-align in 16-bit
words per V4L2 ABI. Y at base+0, interleaved CbCr right
after Y plane (per format spec for single-plane P010).
Strips source stride padding; respects destination stride.
- daedalus_decoder_run_request dispatches on
req->capture_pix_fmt (NV12M → pack_nv12_to_planes; P010
→ pack_p010_to_plane; else warn + skip).
- Includes <linux/videodev2.h> for fourcc constants.
Verification on hertz (Pi 5, 6.12.75+rpt-rpi-2712):
1080p throughput baseline (30 frames testsrc, dmabuf path):
VP9 1080p: mean 12.0 ms, p99 15.9 ms, fps **83.1**, byte-exact ✓
AV1 1080p: mean 15.4 ms, p99 41.0 ms, fps **65.0**, byte-exact ✓
H.264 1080p: mean 11.3 ms, p99 21.5 ms, fps **88.3**, byte-exact ✓
All 2-3× over the 30fps-floor-is-fine criterion.
HDR / 10-bit 1080p P010:
10 frames, 62 MB output, fps **48.8**, byte-exact vs
`ffmpeg -pix_fmt p010le -f rawvideo`.
Small-frame P010 (320×240): fps 966 — fixed daemon overhead
dominates at low resolutions.
v4l2-compliance unchanged from 8.7: 49/49 passing.
Format enumeration confirms NM12 + P010 on CAPTURE.
Clean SIGTERM + rmmod; no kernel oops/WARN.
Roadmap update (docs/roadmap.md):
- 8.8 marked closed with closure-doc reference, including
the explicit "QPU substitution not needed" rationale.
- 8.9 reshaped: libva-v4l2-request consumer integration
(per project_consumer_target memory) — the actual
user-facing endpoint.
Per correctness-before-speed:
- Measured first; QPU work explicitly justified-out via data.
- Byte-exact pixel comparison for every codec/format combo
(NV12: VP9, AV1, H.264; P010: VP9 10-bit at 320×240 and
1080p).
- AU grouping in the Annex-B parser is the correct
semantic boundary, not just a workaround.
- vb2_plane_size for payload generalises to any plane
count, not hardcoded to 2.
Phase 8.9 next: libva-v4l2-request integration — close
the loop from YouTube/Firefox to /dev/video0 + daemon
playback.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
c7f6fb90cb |
Phase 8.6: dmabuf + AV1 + H.264 + stateless controls
Removes the Phase 8.5 64 KiB frame-size cap by exporting CAPTURE
buffers as dmabuf-fds the daemon mmaps and writes pixels into
directly. Adds AV1 + H.264 codec support, V4L2 stateless control
registration, and the compliance polish that brings the driver
to 47/48 v4l2-compliance pass.
Protocol (include/daedalus_v4l2_proto.h):
- struct daedalus_req_decode grew capture-buffer metadata
(width/height/pix_fmt/num_planes + per-plane size+stride).
- New DAEDALUS_IOC_GET_DMABUF ioctl on the chardev: daemon
asks for a per-plane dmabuf fd, kernel calls vb2_core_expbuf
in daemon task context so the fd lands in the daemon's table.
Kernel m2m driver (kernel/daedalus_v4l2_main.c):
- Both queues switched to vb2_dma_contig_memops. OUTPUT was
vmalloc in 8.5; the switch is needed because vmalloc doesn't
honour V4L2_MEMORY_FLAG_NON_COHERENT and v4l2-compliance's
REQBUFS test rejected the driver because of it. We still
read bitstream via vb2_plane_vaddr (dma_contig gives a
kernel virtual address just like vmalloc did).
- dma_coerce_mask_and_coherent(DMA_BIT_MASK(32)) in probe.
- queue_setup populates alloc_devs[plane] = &pdev->dev for
both queues; allow_cache_hints=1 on both.
- daedalus_export_capture_dmabuf(cookie, plane, flags, *fd):
walks inflight list, calls vb2_core_expbuf on the CAPTURE
buffer in the caller's (daemon's) task context.
- device_run fills the new REQ_DECODE capture fields from
ctx->dst_fmt and maps ctx->src_fmt.pixelformat to
DAEDALUS_CODEC_VP9 / _AV1 / _H264 (was hard-wired to VP9).
- daedalus_complete_resp_frame handles both the 8.5 inline
path (kept for debugging) and the 8.6 dmabuf path (pixels
already in CAPTURE buffer, just set payload from metadata).
- enum_fmt advertises all 3 OUTPUT formats (VP9F, AV1F, S264).
- try_fmt preserves userspace colorspace fields instead of
overwriting with REC709 defaults (fixes 8.5 compliance fail).
- s_fmt propagates OUTPUT colorspace → CAPTURE (stateless
decoder round-trip test at v4l2-test-formats.cpp:958).
- 12 V4L2 stateless controls registered per open (VP9_FRAME,
VP9_COMPRESSED_HDR, H264_SPS/PPS/SCALING/PRED_WEIGHTS/
SLICE_PARAMS/DECODE_PARAMS, AV1_FRAME/SEQUENCE/
TILE_GROUP_ENTRY/FILM_GRAIN). Daemon ignores values (FFmpeg
re-parses); registration is what makes libva-v4l2-request
see us.
Kernel chardev (kernel/daedalus_v4l2_chardev.c):
- New unlocked_ioctl dispatching DAEDALUS_IOC_GET_DMABUF to
daedalus_export_capture_dmabuf.
- debugfs test_decode cookies unified with the m2m cookie
allocator via shared daedalus_next_cookie() — kills the
Phase 8.5 namespace collision.
Daemon (daemon/src/...):
- New dmabuf_capture.{c,h}: GET_DMABUF + mmap each plane on
REQ_DECODE; munmap + close on completion. O_RDWR | O_CLOEXEC
is essential — vb2_core_expbuf extracts O_ACCMODE from flags
and exports read-only by default (caught on first run; mmap
-EACCES on PROT_WRITE).
- decoder.{c,h}: lazily opens AV1 + H.264 AVCodecContexts in
addition to VP9 (dropped the -ENOSYS stubs). pack_nv12_to_planes
writes Y line-by-line into planes[0] with planes[0].stride;
interleaves Cb/Cr into planes[1] with planes[1].stride.
- chardev_client.c handle_req_decode: opens dmabuf planes,
runs decode (pixels land in CAPTURE buffer directly), closes
planes, sends metadata-only RESP_FRAME. No wire-pixel
allocation.
Test harness (tools/test_m2m_decode.c):
- Optional 5th arg `codec` (vp9 | av1 | h264). Same client
drives all three codecs.
Verification on hertz (Pi 5, 6.12.75+rpt-rpi-2712):
Bit-exact end-to-end vs `ffmpeg -pix_fmt nv12`:
VP9 1920x1080 3,110,400 bytes MATCH
AV1 128x96 18,432 bytes MATCH
H.264 128x96 18,432 bytes MATCH
VP9 1080p went through the full dmabuf path with no chardev
payload bloat — the same chardev that capped at 64 KiB in 8.5
now ferries metadata only and lets the daemon mmap+write a
3.1 MB frame directly into the V4L2 client's buffer.
v4l2-compliance:
Phase 8.1: 44/48
Phase 8.5: 44/48 (different fails after m2m landed)
Phase 8.6: 47/48
Only remaining: VIDIOC_(TRY_)DECODER_CMD (needs media
controller — explicitly Phase 8.7 work).
11 standard compound controls visible:
vp9_frame_decode_parameters, vp9_probabilities_updates,
h264_sequence_parameter_set, h264_picture_parameter_set,
h264_scaling_matrix, h264_prediction_weight_table,
h264_slice_parameters, h264_decode_parameters,
av1_sequence_parameters, av1_frame_parameters,
av1_film_grain (av1_tile_group_entry refused by hdl->error
on this kernel — skipped silently).
Clean SIGTERM + rmmod, no oops/WARN.
Roadmap update (docs/roadmap.md):
- Phase 8.6 marked closed with the closure-doc reference.
- Phase 8.7 reshaped to (1) media controller, (2) perf +
daedalus_dispatch_* substitution, (3) HDR/10-bit, (4)
long-form multi-frame streaming.
Per correctness-before-speed:
- Real V4L2 dmabuf via vb2_core_expbuf (not a sideband
fd-passing hack).
- O_RDWR access mode threaded through correctly.
- Strict pixel-byte comparison against ffmpeg, not "looks
right" eyeballing.
- Each compliance edge documented with the underlying test
source-line + the fix.
- All resource paths cleaned (munmap + close per plane on
every exit, including error paths).
Phase 8.7 next: media controller binding (closes last
compliance fail), per-frame profiling, QPU dispatch
substitution targeting 30fps@1080p from
30fps-floor-is-fine memory.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
6f4b580f7c |
Phase 8.5: full V4L2 m2m driver, VP9 decode via QBUF/DQBUF
Replaces the Phase 8.4 debugfs-triggered chardev path with a
real V4L2 m2m driver. Userspace clients now drive decoding the
standard way — S_FMT / REQBUFS / QBUF on the OUTPUT (bitstream)
queue, DQBUF on the CAPTURE (NV12M) queue. Kernel device_run
packs the bitstream into REQ_DECODE; daemon decodes via FFmpeg;
RESP_FRAME's inline NV12 pixel payload lands in the CAPTURE
buffer. Phase 8.6 swaps the inline payload for dmabuf so big
frames stop being capped at 64 KiB.
Kernel (daedalus_v4l2_main.c, rewritten + main.h added):
- Per-open struct daedalus_ctx: v4l2_fh, m2m_ctx, ctrl_handler,
per-queue v4l2_pix_format_mplane.
- Two vb2_queues (vb2_vmalloc_memops for both — no DMA needed
yet; 8.6 switches CAPTURE to dma_contig for dmabuf-export):
OUTPUT = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE, VP9_FRAME
CAPTURE = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE, NV12M
- Full v4l2_ioctl_ops table: querycap, enum_fmt, g/s/try_fmt
for both queues, reqbufs/querybuf/qbuf/dqbuf/create_bufs/
prepare_buf/expbuf/streamon/streamoff via v4l2_m2m_ioctl_*
helpers.
- v4l2_m2m_ops.device_run: peeks next OUTPUT buf, builds
REQ_DECODE inline with the bitstream bytes, enqueues with an
auto-incrementing cookie, stores {ctx, src_buf, dst_buf} in
a per-device inflight list. Job stays open until RESP_FRAME.
- daedalus_complete_resp_frame(): pops the inflight entry,
memcpys inline NV12 pixels into the CAPTURE buffer (Y plane
+ interleaved CbCr), finishes via
v4l2_m2m_buf_done_and_job_finish — NOT plain buf_done +
job_finish, which leaves the src buf on the m2m queue and
causes device_run to immediately re-run on the same input
(caught on first run; second REQ_DECODE for same bitstream +
eventual oops in stop_streaming on teardown).
Kernel (daedalus_v4l2_chardev.c):
- RESP_FRAME handler now hands inline pixel payload to
daedalus_complete_resp_frame so it lands in the CAPTURE
vb2 buffer. Existing PONG and debugfs test_decode paths still
work; the latter produces a harmless ratelimited "unknown
cookie" since it bypasses V4L2 m2m.
Daemon (decoder.c, decoder.h):
- daedalus_decoder_run_request signature extended with
(nv12_out, nv12_cap, nv12_used). After the FNV-1a digest the
decoder packs YUV420P into NV12 in the caller's buffer: Y
plane line-by-line stripped of stride padding; Cb/Cr
interleaved into a single chroma plane. Truncation silent —
kernel only memcpys what fits in the CAPTURE plane.
Daemon (chardev_client.c):
- handle_req_decode allocates a response buffer sized for the
full chardev payload, lets decoder fill the pixel area
after the resp_frame struct, sends the full payload via the
existing send_response.
Test client (tools/test_m2m_decode.c, new):
- Minimal V4L2 m2m client: S_FMT both queues, REQBUFS 1 each,
mmap+fill OUTPUT, QBUF both, STREAMON, poll, DQBUF, dump
CAPTURE planes to a raw NV12 file. ~250 LOC; verifies the
whole flow without needing v4l2-ctl framing.
Roadmap update (docs/roadmap.md):
- Phase 8.4 retitled "daemon ↔ kernel decode round-trip"
to reflect what actually shipped (vs. the original V4L2-
ioctl-driven plan which moved here).
- Phase 8.5 retitled "full V4L2 m2m driver" with closure
status.
- Phase 8.6 reshaped to two tracks: dmabuf + AV1/H.264/
stateless controls + media controller. Adds the punch list
of v4l2-compliance failures (DECODER_CMD, S_FMT colorspace)
that 8.6 will fix.
Verification on hertz (Pi 5, 6.12.75+rpt-rpi-2712):
Kernel + daemon build clean (-Wall -Wextra clean both sides).
Test harness drives one VP9 keyframe end-to-end:
OUTPUT REQBUFS -> 2
CAPTURE REQBUFS -> 2
QBUF OUTPUT[0] bytesused=1566
QBUF CAPTURE[0]; STREAMON both
poll revents=0x5
DQBUF OUTPUT[0] flags=0x4001 (DONE)
DQBUF CAPTURE[0] flags=0x4000 payloads=[12288, 6144]
wrote 12288 Y + 6144 UV bytes to /tmp/out_m2m.nv12
Pixel correctness vs reference:
ffmpeg -i vp9_small.ivf -pix_fmt nv12 -f rawvideo -y ref.nv12
cmp /tmp/out_m2m.nv12 /tmp/ref.nv12 → match ✓
Byte-for-byte identical to FFmpeg's stock CPU decode.
v4l2-compliance: detected as Stateless Decoder; most ioctls
pass; two expected fails documented in closure doc
(DECODER_CMD/media controller, S_FMT colorspace).
Clean teardown: SIGTERM the daemon, rmmod the module, no
oops/WARN in dmesg.
Per correctness-before-speed:
- Real V4L2 ioctl table (not stubs); uses v4l2-core helpers
where they exist instead of reinventing.
- v4l2_m2m_buf_done_and_job_finish (not the manual sequence)
to keep scheduler state consistent.
- Bit-exact reference comparison, not just "looks right."
- Documented every compliance failure with the planned fix.
- All resource paths (kmalloc/kfree, inflight list cleanup,
src/dst buf removal in stop_streaming) handled on every
error branch.
Phase 8.6 next: dmabuf-export for CAPTURE (removes 64 KiB
frame-size cap), add AV1+H.264 codecs, add V4L2 stateless
controls + media controller binding, fix the colorspace +
cookie-namespace compliance issues.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
2a449632b9 |
Phase 8.4: daemon ↔ kernel decode round-trip (VP9 end-to-end)
Wires the Phase 8.3 FFmpeg loader through the Phase 8.2 chardev
bridge: kernel injects REQ_DECODE carrying a raw VP9 access unit,
daemon hands the bitstream to libavcodec via dlopen, sends
RESP_FRAME back with a content-dependent FNV-1a digest of the
decoded YUV planes. Pure CPU decode for now — Phase 8.5 swaps in
dmabuf + QPU dispatch.
Protocol (include/daedalus_v4l2_proto.h):
- New REQ_DECODE (kernel→daemon) and RESP_FRAME (daemon→kernel)
message types, with fixed-size payload structs.
- New DAEDALUS_CODEC_VP9/AV1/H264 enum (wire-stable so 8.6's
AV1+H.264 work doesn't move existing values).
- New DAEDALUS_DECODE_* status enum (OK / NO_FRAME / ERR_OPEN /
ERR_SEND / ERR_RECV / ERR_CODEC).
- Converted the prior `enum daedalus_msg_type` to #defines —
high-bit values exceed INT_MAX and tripped -Wpedantic on
userspace; kernel uABI headers use the same idiom.
Kernel (kernel/daedalus_v4l2_chardev.c):
- New debugfs entry /sys/kernel/debug/daedalus_v4l2/test_decode:
writing raw bitstream bytes wraps them in a REQ_DECODE
(codec=VP9 for Phase 8.4) and enqueues with an
auto-incrementing cookie.
- daedalus_chardev_write learned RESP_FRAME: parses the payload
and emits a single pr_info line with decode metadata. Keeps
existing PONG handling on the default arm.
Daemon (daemon/src/...):
- chardev_client.{c,h} — opens /dev/daedalus-v4l2, blocking read
loop, single-buffer write() responses (kernel chardev has only
.write, not .write_iter, so writev lands as -EINVAL —
discovered the hard way during first run).
- decoder.{c,h} — lazily-opened AVCodecContext per codec, shared
AVPacket/AVFrame pair, descriptor-driven plane walker
(av_pix_fmt_desc_get) so the same hash path covers YUV420P,
YUV422P, YUV444P, GBRP and other 8-bit planar layouts.
Generalised after first run decoded testsrc as GBRP (71)
rather than the assumed YUV420P.
- `daemon` command in main.c opens the chardev and runs the loop
until SIGINT/SIGTERM. Cookie correlation handled end-to-end.
- ffmpeg_loader gained av_pix_fmt_desc_get (23 symbols total).
Build:
- CMakeLists adds chardev_client.c + decoder.c; explicit
-I../include for the shared protocol header.
- Still -Wall -Wextra -Wpedantic clean.
Verification on hertz (Pi 5, 6.12.75+rpt-rpi-2712):
$ ffmpeg ... -pix_fmt yuv420p -c:v libvpx-vp9 -frames:v 1 \
-y /tmp/vp9_test.ivf
$ python3 ... strip IVF framing → vp9_keyframe.bin (3268 B)
$ sudo insmod kernel/daedalus_v4l2.ko
$ daedalus_v4l2_daemon -v daemon &
$ sudo dd if=vp9_keyframe.bin \
of=/sys/kernel/debug/daedalus_v4l2/test_decode
daemon: REQ_DECODE cookie=2 → decoded yuv420p 320x240
fnv1a=0x6ef10d71 luma=76800 chroma=38400
kernel: RESP_FRAME cookie=2 status=0 320x240 pixfmt=0
fnv1a=0x6ef10d71 ← matches daemon ✓
Hash properties verified:
cookie=2 testsrc 3268 B → 0x6ef10d71 (first decode)
cookie=3 red 44 B → 0x7f6e5dc5 (content-dependent ✓)
cookie=4 testsrc 3268 B → 0x6ef10d71 (deterministic ✓)
cookie=5 64 B random → status=101 (ERR_SEND, daemon alive)
Daemon survives bad input (FFmpeg "Invalid sync code" wrapped
into structured ERR_SEND response). Clean SIGTERM shutdown,
clean rmmod.
Phase 8.4 acceptance criteria met:
- ✓ end-to-end kernel→daemon→FFmpeg→kernel round-trip
- ✓ cookie correlation per request/response pair
- ✓ content-dependent + deterministic digest
- ✓ structured error responses (no daemon crash on bad input)
- ✓ clean teardown (SIGTERM + rmmod)
- ✓ builds clean on both kernel kbuild and daemon CMake
Per correctness-before-speed:
- Real chardev I/O (no shortcuts, no select-loop hacks)
- Real FFmpeg AVCodecContext lifecycle (lazily opened, properly
freed on cleanup)
- Descriptor-driven plane walk (generalises across pix_fmts)
- Structured error path (not just log-and-continue)
- All resource paths cleaned up on every error branch
- Documented why FNV-1a digest, why write() not writev(), why
pix_desc walk in docs/phase_8_4_closure.md
Phase 8.5 next: V4L2 m2m queue submits REQ_DECODE from
vidioc_qbuf; dmabuf carries actual pixel data so the chardev's
64 KiB cap doesn't gate frame size; begin substituting
daedalus_dispatch_* into the daemon's decode path.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
873a04c622 |
Phase 8.3: userspace daemon scaffold + FFmpeg dlopen + parse path
Builds the daemon executable per the locked Phase 8 architecture
(Option γ: dlopen FFmpeg at runtime). Phase 8.3 scope: parse
path validation only — no V4L2 wiring, no decode, no chardev
connection.
Components:
- daemon/CMakeLists.txt — CMake with -Wall -Wextra -Wpedantic
clean. pkg-config for FFmpeg headers; only -ldl + -lpthread
at link time.
- daemon/src/main.c — entry point, signal handlers
(SIGINT/SIGTERM), command dispatcher. Currently `parse <file>`.
- daemon/src/ffmpeg_loader.{c,h} — runtime FFmpeg loader.
dlopens libavformat.so.61, libavcodec.so.61, libavutil.so.59.
Resolves 22 function pointers using POSIX-recommended
*(void**)& dlsym idiom (per POSIX.1-2017 dlsym(3p) Rationale).
- daemon/src/parser.{c,h} — demux loop via avformat_open_input +
av_read_frame. Per-frame logging on -v.
- daemon/src/log.{c,h} — logging facade (stderr Phase 8.3;
syslog/journal planned for 8.5+).
Verification on hertz:
$ ffmpeg -f lavfi -i testsrc=duration=2:size=320x240:rate=30 \
-c:v libvpx-vp9 -y /tmp/testsrc.ivf
$ daedalus_v4l2_daemon parse /tmp/testsrc.ivf
[INFO] FFmpeg loaded: 7.1.3-0+deb13u1+rpt1 (libavformat 61.7.100)
[INFO] video stream #0: codec=vp9 (Google VP9) 320x240, 0/0 fps
[INFO] parse complete: 60 frames (1 key) total 17859 bytes
Error paths verified:
- Missing file → "avformat_open_input(...): code -2", exit 1
- No command → usage message, exit 2
- Bad command → usage message, exit 2
Per correctness-before-speed:
- Real CMake (no Makefile hacks)
- pkg-config for headers
- POSIX-conformant dlsym pattern (no -Wpedantic suppression)
- Real signal handling + proper exit codes
- Real logging with timestamp + level
- Headers included at compile-time for type safety; dlopen
decouples runtime
- All FFmpeg resources freed on every exit path
- Builds clean on -Wall -Wextra -Wpedantic
Phase 8.3 acceptance criteria met:
- ✓ daemon binary builds
- ✓ dlopen FFmpeg at runtime
- ✓ demux a VP9 IVF file end-to-end
- ✓ per-frame metadata logged correctly
- ✓ frame count + keyframe count + byte total accurate
Phase 8.4 next: wire daemon to /dev/daedalus-v4l2 chardev,
add REQ_DECODE / RESP_FRAME handling, drive VP9 decode
end-to-end via daedalus_dispatch_* from daedalus-fourier.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
|
||
|
marfrit
|
c7d8050cc9 |
Initial scaffold: daedalus-v4l2 sibling repo
V4L2 stateless decoder for Pi 5, backed by sibling
daedalus-fourier kernel library (VP9 + AV1 CDEF + H.264 video
decode kernels on VideoCore VII compute + ARM NEON).
Architecture locked 2026-05-18 by mfritsche per
daedalus-fourier/docs/phase8_scoping.md:
- Option B: Linux kernel V4L2 shim + userspace daemon (not
v4l2loopback). Real /dev/videoNN; proper DRM PRIME for
browser zero-copy.
- Option γ: dlopen FFmpeg at runtime as parser. No vendoring;
fastest to v1.
- Sibling repo (this repo): V4L2-side work outside of
daedalus-fourier so kernel-library API stays clean.
Components:
kernel/ - Linux out-of-tree kernel module (GPLv2; V4L2
device + chardev bridge to userspace daemon)
daemon/ - userspace decoder daemon (BSD-2-Clause; links
libdaedalus_core.a from sibling; dlopens FFmpeg)
docs/ - architecture + 7-phase roadmap (8.1..8.7)
include/ - shared headers between kernel and daemon
Roadmap (7 sub-phases, ~1 week each):
8.1 kernel skeleton (/dev/videoNN with no-op ioctls)
8.2 chardev bridge (kernel ↔ daemon ping-pong)
8.3 daemon FFmpeg dlopen + parse path
8.4 VP9 end-to-end via daedalus_dispatch_*
8.5 dmabuf / DRM PRIME for zero-copy
8.6 AV1 + H.264 codec support
8.7 performance: hit 30fps@1080p (project floor)
No code yet — only README + design docs + directory structure.
First implementation work starts in Phase 8.1 next session.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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