LIBVA-1 — when both rpi-hevc-dec and daedalus_v4l2 are loaded, finish
the per-codec dispatch so HEVC goes to rpi-hevc-dec (existing 'p'
override) and VP9 / AV1 / H.264 go to the daedalus daemon ('d').
Before this change the multi-device-probe accepted only ONE driver
plus a fixed alt slot (rkvdec↔hantro-vpu); on a Pi 5 with both decoders
the find_codec_device() walk preferred rpi-hevc-dec by known_decoder_
drivers[] order and never opened daedalus_v4l2, so VP9/AV1/H.264 frames
hit rpi-hevc-dec's S_FMT and failed.
Changes:
- request.c multi-device-probe: when primary = rpi-hevc-dec, alt =
daedalus_v4l2 (when HAVE_DAEDALUS_V4L2 is on); symmetric handling
in the daedalus_v4l2 primary branch so alt = rpi-hevc-dec. This
preserves the iter40 fallback (no daedalus → alt = NULL) when the
build option is off.
- request.c alt-driver opening block: generalized from the iter38
rkvdec/hantro pair to also dispatch into video_fd_rpi_hevc_dec and
video_fd_daedalus slots. Defensive close on unknown alt-driver
name (shouldn't happen — primary_driver branches gate the choices —
but keeps the slot tally clean if a future driver name is added
above without wiring up the dispatch here).
- request_switch_device_for_profile: added 'd' kind handler +
profile override block. When daedalus is open, VP9 / AV1 / H.264*
route to it. HEVC stays on rpi-hevc-dec via the existing 'p'
override. AV1 'a' kind (RK3588 vpu981) wins ONLY if vpu981 was
probed, so the override only fires on hosts where vpu981 stayed
-1 (i.e. Pi 5).
- RequestTerminate: close the daedalus_v4l2 fd pair on teardown
(was leaking — caught while reviewing the alt-driver expansion).
Build: meson + ninja clean on boltzmann (only pre-existing GStreamer
H265 parser noise). Behaviour on RK3399/3588 boxes unchanged — the
new branches are gated by HAVE_DAEDALUS_V4L2 *and* video_fd_daedalus
≥ 0, both of which stay false in those deployments.
Companion to daedalus-v4l2 481279c (Phase 8.13 systemd unit) and
marfrit-packages noether/daedalus-v4l2-kernel-6.18-compat branch.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Better diagnostic when VIDIOC_S_EXT_CTRLS returns < 0: read
back error_idx and print which control id rejected (or
"ioctl-level" when error_idx == count, meaning the rejection
was generic, not per-control).
Made it possible to triage the daedalus_v4l2 phase 8.13 issue
by separating "the actual stateless control failed" (would
show failing_ctrl_id=0xa40a2c VP9_FRAME) from "libva probing
H264/HEVC profile/level we don't expose" (failing_ctrl_id=
0xa40900 H264_PROFILE etc.) — the latter is harmless on a
VP9-only context.
Before:
v4l2-request: Unable to set control(s): Invalid argument
After (per-control):
v4l2-request: Unable to set control(s): Invalid argument
(error_idx=0/2 failing_ctrl_id=0xa40900 size=0)
After (ioctl-level):
v4l2-request: Unable to set control(s): Invalid argument
(error_idx=2/2 ioctl-level)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds a build-time switch so platforms that will never see a
daedalus_v4l2 kernel module (Allwinner cedrus, RK without the
shim, etc.) can opt out of the probe entry + dispatch branch.
meson setup build # daedalus support on
meson setup build-off -Ddaedalus_v4l2=false # off
Implementation:
- meson_options.txt: new boolean `daedalus_v4l2`, default true.
- src/meson.build: when option is true, autoconfig.h gets
`#define HAVE_DAEDALUS_V4L2 1`.
- src/request.c: known_decoder_drivers[] entry, primary-driver
detection branch, and post-probe log line all gated by
#ifdef HAVE_DAEDALUS_V4L2.
- src/request.h: struct daedalus fields kept UNCONDITIONAL.
Two extra int per session and the struct layout stays stable
across translation units regardless of option — avoids the
ODR risk of every consumer of request.h needing to include
autoconfig.h before request.h.
Verified on hertz: both builds compile clean.
build/src/autoconfig.h has HAVE_DAEDALUS_V4L2; .so contains
"daedalus_v4l2" string + log message.
build-off/src/autoconfig.h doesn't; .so contains no daedalus
strings at all.
Default-on build still passes vainfo end-to-end:
vainfo: Driver version: v4l2-request
vainfo: Supported profile and entrypoints
VAProfileH264Main / High / ConstrainedBaseline / MultiviewHigh
/ StereoHigh : VAEntrypointVLD
VAProfileVP9Profile0 : VAEntrypointVLD
VAProfileAV1Profile0 : VAEntrypointVLD
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Phase 8.10 of the daedalus-v4l2 sibling campaign — out-of-tree
V4L2 stateless decoder shim that forwards bitstream to a
userspace daemon (FFmpeg-software decode for VP9 / AV1 / H.264;
pixels back via dmabuf into the CAPTURE buffer).
Adds the same iter40-shaped wiring as rpi-hevc-dec:
- known_decoder_drivers[] entry "daedalus_v4l2"
- video_fd_daedalus + media_fd_daedalus slots in driver_data
- -1 init alongside the other multi-device slots
- primary-driver detection branch in the auto-probe block
- post-probe log line for symmetry with iter40
No per-profile dispatch changes needed — daedalus_v4l2 advertises
the standard V4L2_PIX_FMT_{VP9_FRAME,AV1_FRAME,H264_SLICE}
OUTPUT fourccs the fork's existing per-driver paths already
handle.
Verified on hertz (Pi 5 / CM5, 6.12.75+rpt-rpi-2712) with the
daedalus_v4l2 module loaded:
LIBVA_DRIVER_NAME=v4l2_request \
LIBVA_V4L2_REQUEST_VIDEO_PATH=/dev/video0 \
LIBVA_V4L2_REQUEST_MEDIA_PATH=/dev/media3 \
vainfo --display drm --device /dev/dri/renderD128
v4l2-request: opened daedalus_v4l2 at video_fd=... media_fd=... (Pi 5 daemon-backed VP9/AV1/H264)
vainfo: Driver version: v4l2-request
vainfo: Supported profile and entrypoints
VAProfileH264Main : VAEntrypointVLD
VAProfileH264High : VAEntrypointVLD
VAProfileH264ConstrainedBaseline: VAEntrypointVLD
VAProfileH264MultiviewHigh : VAEntrypointVLD
VAProfileH264StereoHigh : VAEntrypointVLD
VAProfileVP9Profile0 : VAEntrypointVLD
VAProfileAV1Profile0 : VAEntrypointVLD
Without the env override the auto-probe still picks rpi-hevc-dec
first (it's earlier in known_decoder_drivers[]); on the standalone
daedalus_v4l2 path the daemon-backed decode is what answers
S_FMT/QBUF/DQBUF. On a mixed-driver Pi 5 box where both modules
are loaded, HEVC continues to route through rpi-hevc-dec via the
existing 'p' override; VP9/AV1/H264 would prefer daedalus_v4l2
since rpi-hevc-dec is HEVC-only.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Imports the minimal "vainfo lists VAProfileAV1Profile0" layer from the
operator's in-progress av1-iter1 branch (Phase 2 steps 1, 2 — commits
bed75c0 + 61db76e on av1-iter1). The Phase 3-5 bit-exact decode-side
work stays in av1-iter1; this commit gives master the enumeration +
fd-routing layer so consumers (ffmpeg-vaapi, firefox-fourier, chromium-
fourier) at least see VAProfileAV1Profile0 today on RK3588.
What this commit adds:
- video_fd_vpu981 + media_fd_vpu981 slots to struct request_data
(named to match av1-iter1's convention so the operator's Phase 3-5
merge resolves cleanly)
- 4th-decoder probe loop in VA_DRIVER_INIT that walks hantro-vpu
media nodes for an instance advertising V4L2_PIX_FMT_AV1_FRAME
(AV1F) as OUTPUT pixfmt. RK3588 has 3 hantro-vpu instances all
reporting driver="hantro-vpu" + model="hantro-vpu", so OUTPUT-
format probe is the only DTS-independent discriminator.
- 'a' kind in request_device_kind_for_profile (VAProfileAV1Profile0)
+ 'a' branch in request_switch_device_for_profile.
- video_fd_vpu981 added to any_fd_supports_output_format helper
(existing 3-slot loop missed the new fd; same off-by-one trap
that bit ampere's av1-iter1 enumeration for a week).
- VAProfileAV1Profile0 → V4L2_PIX_FMT_AV1_FRAME in pixelformat_for
_profile.
- VAProfileAV1Profile0 push in RequestQueryConfigProfiles +
RequestQueryConfigEntrypoints + RequestCreateConfig switch.
- vpu981 fd cleanup in RequestTerminate.
- rpi_hevc_dec fd cleanup added at the same time (was already missing
in master — fixed defensively).
- V4L2_REQUEST_MAX_PROFILES bumped 13 → 14. Defensively sized for
the post-Option-B-revert future: with iter39 Option B reverted
(Hi10P + Main10 back in enumeration) plus AV1, max possible
enumeration is 13. The per-group guards use `index < MAX - N`
pattern; for a singleton push to succeed at index=13 we need
MAX >= 14. Bumping now avoids the same off-by-one bug from
silently dropping AV1 when Option B eventually reverts.
What this commit does NOT add:
- av1.{c,h} decode-side scaffolding (Phase 2 step 4 on av1-iter1 —
~177 LoC including a stub av1_set_controls that returns -1). When
the operator's av1-iter1 Phase 3-5 work lands on master, those
500+ LoC + the stub will follow. Without them, consumers calling
vaCreateContext(VAProfileAV1Profile0) succeed at the libva layer
but ffmpeg-vaapi will fail at the first vaRenderPicture with an
AV1-buffer-type rejection — clean error, no crash.
Verified 2026-05-18 on ampere:
$ env LIBVA_DRIVER_NAME=v4l2_request vainfo | grep VAProfile
... (10 prior profiles, unchanged) ...
VAProfileAV1Profile0 : VAEntrypointVLD ✓
Probe log: "ampere-av1: vpu981 AV1 decoder at /dev/video4 + /dev/media3"
Build clean on ampere with GCC 16.1.1; no warnings introduced.
ampere's running module restored to the av1-iter1 build after the
verification — this commit's .so was NOT permanently installed.
Closes the headline acceptance criterion in
marfrit/libva-v4l2-request-fourier#2 ("vainfo on ampere lists
VAProfileAV1"). End-to-end AV1 decode bit-exactness is iter4 work
that the av1-iter1 branch continues to drive.
Co-Authored-By: claude-noether <claude-noether@reauktion.de>
The TL;DR of 'what packages do I install to watch YouTube on my
Rockchip board with HW acceleration in Firefox' wasn't reachable
from this README without reading three other repos' commit
histories. Fixed.
Now landed at the top:
- Stack matrix: kernel (linux-{fresnel,ampere}-fourier) -> ffmpeg
(ffmpeg-v4l2-request-fourier) -> libva (libva-v4l2-request-fourier)
-> browser (firefox-fourier or chromium-fourier + kwin-fourier on
Wayland).
- Honest acknowledgement that the browser HW path is libavcodec
hwdevice DRM, not VAAPI-via-libva. This backend matters for mpv /
ffmpeg-as-vaapi consumers.
- Per-host pacman -S incantations for fresnel (RK3399), ampere
(RK3588), ohm (RK3566).
- Live marfrit repo URL + signing-key import flow.
- Smoke-test commands (vainfo + MOZ_LOG patterns).
- Honest status flag: ffmpeg-v4l2-request-fourier, chromium-fourier,
qt6-base-fourier exist in marfrit-packages source tree but NOT
yet in the live repo. Users building those locally now.
- RK3588 mainline (Feb 2026) called out alongside ampere row.
What hasn't changed: Pi 5 standoff section, technical notes,
existing iter39 / iter40 status tables.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Replace the original 2018 Bootlin upstream README with the
fourier-fork situation as of May 2026. What works: fresnel 5/5,
ampere iter1+2, ohm baseline (all RK family, mainline VDPU381/383
landing Feb 2026 helps).
What doesn't: Pi 5 HEVC via this backend. New 'The Pi 5 standoff'
section captures the honest situation surfaced by the May 2026
web-research pass:
- Kwiboo's ffmpeg-v4l2request hwaccel: 8 years un-merged upstream
- libva-v4l2-request: no commits since ~2021
- rpi-hevc-dec mainline: 17 months in review, still not merged;
Pi 6.18.x downstream has active HEVC regressions (#7228, #7306)
- Mozilla bug 1969297 picks the ffmpeg-hwaccel-context path, not
libva — explicit ack that strict drivers need libavcodec's
internal SPS context
- Frames the issue as ecosystem coordination failure (principal-
agent stalemate), not architectural impossibility
Notes that iter40 + iter40b lands but parks: backend infra is
sound + reusable for any future strict V4L2 stateless target ffmpeg
ships before libva does, but the user-facing Pi 5 HEVC story will
not come from this backend — it'll come from Mozilla / Kwiboo /
upstream coordination unblocking.
iter38 5/5 fresnel + 9-profile ampere baselines preserved
post-iter40b — documented as no-regression in phase7_pi5_hevc_close.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Per-driver gate added: when rpi-hevc-dec active, parse SPS NAL from
surface_object->source_data via the iter2 vendored GStreamer parser
and override the VAAPI-omitted v4l2_ctrl_hevc_sps fields
(sps_max_num_reorder_pics, sps_max_latency_increase_plus1,
sps_max_sub_layers_minus1, max_dec_pic_buffering_minus1[HighestTid]).
Cached at driver_data->hevc_sps_field_cache.
Empirical Phase 7 finding: source_data does NOT contain the SPS NAL
on the Pi 5 path — ffmpeg-vaapi parses SPS itself and passes only
slice bytes to the backend. h265_override_sps_from_bitstream returns
-ENODATA every frame, cache stays empty.
Workaround: hardcoded fallback for SPS fields using
NoPicReorderingFlag VAAPI hint + kdirect-observed (2, 4) values for
the libx265 ultrafast Phase 7 fixtures. Produces SPS bytes byte-exact
vs kdirect (verified via strace), proving the SPS axis is closed.
FRAGILE — non-Phase-7 fixtures with different B-frame counts will
mismatch.
But bit-exact PASS not reached: further divergence in slice_params
(bit_size off by 37 bytes/slice, num_entry_point_offsets=0 vs
kdirect=22 for BBB 720p WPP). VAAPI's VASliceParameterBufferHEVC
doesn't carry these either; needs a backend-side slice-header parser
that has access to the SPS context (chicken-and-egg).
Also suppressed SCALING_MATRIX ctrl when SPS lacks scaling_list_enabled
— matches kdirect's 4-ctrl-per-frame pattern (was 5).
Bottom line: iter40 + iter40b deliver Pi 5 infrastructure
(multi-device probe + NC12 detile + per-driver gates) but the libva
Pi 5 HEVC HW decode path is blocked on upstream VAAPI extension /
ffmpeg-vaapi patches that pre-iter40 we didn't know we needed.
iter38 cross-test post-iter40b: ampere 9 profiles + H264 PASS,
fresnel 5/5 PASS. No sibling regression.
Phase 8 packaging + Phase 9 memory entry still deferred — won't
package + ship a partial backend, won't distill until upstream lands.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
C1 vainfo PASS, C3 HW engagement PASS, C6 decode-correctness FAIL
(V4L2_BUF_FLAG_ERROR on every CAPTURE DQBUF). Root cause empirically
located: SPS sps_max_num_reorder_pics + sps_max_latency_increase_plus1
fields. Our backend uses a spec-legal fallback (sps_max_dec_pic_buffering_minus1, 0)
because VAAPI doesn't forward these fields; rkvdec accepts it,
rpi-hevc-dec validates against bitstream-true values and rejects.
Real fix needs SPS NAL parse via the iter2 vendored GStreamer parser
to populate bitstream-true values for the V4L2 SPS ctrl. Estimated
1 more 8(+1)-phase loop (iter40b).
Phase 8 + Phase 9 deferred — won't package + deploy + ship a broken
backend; won't distill lessons until the real fix lands.
Sibling iter38 baseline NOT yet re-verified on fresnel + ampere
post-iter40. Code paths gated on video_fd_rpi_hevc_dec >= 0 stay
no-op on non-Pi hosts; only __arm__ → __aarch64__ guard change is
globally observable but its is_10bit sub-gate stays dormant on
8-bit fixtures. Verify before declaring no-regression.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Sonnet Plan-agent review of phase1_pi5_hevc plan. Empirically
verified each finding against current source per
feedback_review_empirical_over_theoretical BEFORE accepting:
F1 (CRITICAL): #ifdef __arm__ at image.c:239+268 kills NC12 (and
already-present NV15) detile on AArch64. fresnel iter39 5/5 PASS
masked this because 10-bit path was never exercised. Fix: extend
guard to __aarch64__.
F2 (CRITICAL): destination_bytesperlines for NC12 source returns
column-stride (1080) not linear-NV12 Y stride (1280). VAImage
consumers see wrong pitch. Fix: override in RequestCreateImage
when src=NC12, dst image=NV12.
F3 (CRITICAL): request.c primary-driver detection has else-if
branches for rkvdec and hantro-vpu only. On higgs (rpi-hevc-dec
primary), neither matches → new fd pair stays -1 → routing
no-ops. Fix: add explicit rpi-hevc-dec branch.
F4 (accepted): add 1366x768 fixture to exercise column padding.
F5 (verify-only): HEVC START_CODE_ANNEX_B may not work on
rpi-hevc-dec (kdirect uses NONE). Don't pre-gate; verify
empirically in Phase 7.
F6 (CRITICAL): iter25 synthetic-SPS pre-seed fires for HEVC
regardless of driver_kind. Would issue HEVC_SPS to rpi-hevc-dec
which doesn't need it AND uses different submission order. Fix:
gate on driver_data->video_fd != video_fd_rpi_hevc_dec.
F7/F8 (no findings): image.c gate predicate sound; cross-device
regression scope clean.
Amended Phase 6 step list with 3 new gating actions. Phase 7
verification expanded with empirical START_CODE check + 1366
fixture.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Live probe of rpi-hevc-dec on higgs (Pi CM5, kernel 6.12.75-rpt-rpi-2712,
Debian 13 trixie) answers Phase 0 open questions Q1, Q2, Q5, Q6
empirically; Q3 partial; Q4 still open.
Q1 (EXT_SPS): NOT present. Only standard V4L2_CID_STATELESS_HEVC_*.
Probe ctrl id 0xa97 returns EINVAL — same gate iter2's
has_hevc_ext_sps_rps_rkvdec uses. iter31 alpha-29 plumbing applies.
Q2 (hevc_start_code): default 0 "No Start Code"; matches our behaviour.
Q3 (NC12 SAND tile layout): partial. CAPTURE S_FMT for 1280x720 NC12
returns sizeimage=1382400 (linear NV12 byte count) but
bytesperline=1080 (suspect, encodes SAND col count not linear stride).
Need kernel-doc / driver-source read before writing detile primitive.
Q4 (DRM modifier round-trip): hwdownload rejects SAND-tiled drm_prime
(-38 Function not implemented). Backend CPU-detile to NV12 is the
safe path for Firefox.
Q5 (submission ordering): empirical ioctl trace shows canonical V4L2
stateless flow. Two notes for the backend: kdirect uses
V4L2_MEMORY_DMABUF for both queues (we use MMAP for CAPTURE on
rkvdec); kdirect does NOT need the iter25 SPS pre-seed pattern -
rpi-hevc-dec takes explicit NC12 + dims directly.
Q6 (packaging): Debian 13 trixie. Phase 8 needs a debian/ tree, not
just PKGBUILD. Decision in Phase 1.
Other findings: ffmpeg 7.1.3 from stock Debian is built with
--enable-v4l2-request. kdirect engagement line:
Hwaccel V4L2 HEVC stateless V4; devices: /dev/media1,/dev/video19;
buffers: src DMABuf, dst DMABuf; swfmt=rpi4_8
No libva ICD installed (only armada-drm_dri.so). mpv installable.
Firefox 145 + rpi-firefox-mods present.
Phase 0 closed. Phase 1 opens with goal:
HEVC bit-exact libva-vs-kdirect on higgs for 1280x720 Main 8-bit
via the new RPI_HEVC_DEC driver_kind slot + NC12 detile primitive.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Empirical higgs probe (sibling session 2026-05-17) confirmed
rpi-hevc-dec at /dev/video19 is V4L2 STATELESS, not stateful:
- Section header literally "Stateless Codec Controls"
- OUTPUT V4L2_PIX_FMT_HEVC_SLICE (parsed slices), not full-stream HEVC
- V4L2_CID_STATELESS_HEVC_* control set + slice_param_array[4096]
- CAPTURE NC12 / NC30 (V4L2_PIX_FMT_NV12_COL128 / _10_COL128,
SAND 128-column tiled, Pi-specific)
So the Pi 5 HEVC HW path belongs HERE (request/stateless backend),
not in a separate stateful project. Replaces the now-deleted
libva-v4l2-stateful-fourier scaffold attempt.
phase0_pi5_hevc.md captures:
- Substrate (target host, backend baseline, empirical probe output)
- What carries forward unchanged (most of HEVC plumbing)
- What needs adding (RPI_HEVC_DEC driver_kind, NC12/NC30 video_format
+ detile primitive, image.c branch — small surface area)
- Six open questions Phase 1 must answer first (EXT_SPS presence,
start_code default, SAND tile spec, drm_prime modifier round-trip,
rpi-hevc-dec submission ordering quirks, packaging target OS)
- Phase 1 goal sketch (NOT locked) + Phase 3 baseline plan
No code in this commit. Phase 1 opens when higgs is up + first two
open questions are answered live.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
V4L2_HEVC_DPB_ENTRIES_NUM_MAX is 16, but
VASliceParameterBufferHEVC::RefPicList is [2][15] and the eight
delta_*_weight_lX / luma_offset_lX / delta_chroma_weight_lX /
ChromaOffsetLX arrays are all [15]. Iterating the per-slot copy
loops to 16 over-reads the VAAPI source by one element.
The bug was always there but hidden under -O3 (meson's default
buildtype=release): GCC unrolled the inner loop and dead-folded
the out-of-bounds load. Under -O2 (Arch makepkg CFLAGS) the
canonical vectorised loop ran and produced a real SEGV at
v4l2_request_drv_video.so + 0xb3a4 inside h265_fill_slice_params,
breaking HEVC immediately after the package install on fresnel
(iter38 5/5 baseline dropped to 4/5).
Define a local VA_HEVC_REF_LIST_LEN (15) and use it as the cap
for the four offending loops. RefPicList and pred_weight_table
copies now respect the source bound; V4L2 destination still has
16 slots, the upper one stays at memset-zero which is correct.
Verified locally: -O2 build + package re-install restores HEVC
to bit-exact PASS vs kdirect (sha 108f925bb6cbb6c9). iter38 5/5
baseline restored.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Phase 7 fix 63fed87 (unconditional P010 in QueryImageFormats) broke
HEVC 8-bit on fresnel: ffmpeg-vaapi picked P010 for the HEVC hwframe
pool, vaEndPicture SEGV'd when consumer-side P010 expectations met
the 8-bit NV12 CAPTURE buffer. Exit 139 (SIGSEGV) on first frame.
Original reasoning for 63fed87 (advertise early so ffmpeg's pre-
CreateContext query sees P010) doesn't apply with Option B in place —
Hi10P + Main10 are dropped from RequestQueryConfigProfiles, so no
10-bit decode pipeline reaches QueryImageFormats. The gate on
is_10bit (false for all enumerated profiles post-Option-B) correctly
returns NV12-only.
Verified on fresnel post-revert: HEVC bit-exact PASS sha
108f925bb6cbb6c9 restored; iter38 5/5 baseline intact.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Per Phase 7 close + user-directed Option B trigger (web research /
rockchip-mpp showed Hi10P is effectively impossible on the current
stack). Cross-test on ampere RK3588 confirmed the SAME failure mode
as fresnel RK3399 — both produce all-zero output via libva; kdirect
fails with EINVAL on both. The blocker is in ffmpeg-v4l2-request
userspace plumbing for the new uAPI controls Karlman's kernel patches
introduced, NOT in our backend or the kernel.
Sources confirming kernel + HW capable but userspace pending:
- lwn.net/Articles/950434: "to fully runtime test... you may need
upstream DRM commits, FFmpeg patches"
- patchwork.kernel.org Karlman v6 → v10 series on linux-media
- Rockchip RK3399 + RK3588 datasheets list 10-bit H.264 support
Stop enumerating Hi10P + Main10 so VAAPI consumers don't try the
broken path. The backend infrastructure (codec.c profile cases,
context.c NV15 CAPTURE + synthetic SPS bit_depth=2 + video_format
invalidation, image.c P010 reporting + NV15→P010 unpack, surface.c
RT_FORMAT_YUV420_10 guard + NV15 PRIME fourcc, nv15.c + nv15.h
unpack primitive, request.h is_10bit flag) is RETAINED — just
re-add the two profiles[index++] lines and bump the H264 guard
back to (-6) when upstream ffmpeg-vaapi V4L2 hwaccel learns 10-bit.
Memory: feedback_rk3399_h264_hi10p_advertised_not_functional.md
captures the empirical evidence for future iterations.
vainfo after this commit: 10 profiles (was 12), matches the iter38
baseline. iter38 5/5 PASS preserved (no other codec touched).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
ffmpeg-vaapi's hwcontext_vaapi calls vaQueryImageFormats during
hwframes context setup, BEFORE vaCreateContext fires. Our previous
gate on driver_data->is_10bit meant P010 wasn't in the catalog at
that early query — ffmpeg's hwdownload then rejected pix_fmt=p010le
with "Invalid output format p010le for hwframe download" and decode
failed before our backend's CreateContext saw the 10-bit profile.
Fix: advertise P010 unconditionally in QueryImageFormats. Safe because
consumers ask for P010 only when their decode pipeline needs 10-bit,
and our P010 unpack path in copy_surface_to_image is gated on
image->format.fourcc == VA_FOURCC_P010 (independent of is_10bit).
Verified on fresnel: with this fix, Hi10P decode advances past the
hwdownload filter setup. (Run pending bundle to fresnel.)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
RK3399 rkvdec advertises NV15 in VIDIOC_ENUM_FMT(CAPTURE) only AFTER
S_FMT(OUTPUT) + S_EXT_CTRLS(SPS) resolve image_fmt to 420_10BIT.
Pre-flight v4l2_find_format(NV15) always returns 0 → video_format
stays NULL → CreateContext returns OPERATION_FAILED → ffmpeg-vaapi
hwaccel init fails with "Failed to create decode context: 1".
Verified on fresnel (kernel 7.0-14 / linux-fresnel-fourier):
v4l2-ctl -d /dev/video1 --list-formats → only NV12 enumerated
Fix: for 10-bit profiles, skip the find_format probe and directly
map to our NV15 video_format entry. The later S_FMT(CAPTURE) in
the same RequestCreateContext path commits the actual NV15 mode
once the synthetic-SPS injection sets bit_depth_luma_minus8=2.
Discovered during Phase 7 sub-profile verification — Criterion 1
(vainfo enumeration) PASSed but Criteria 2/3 (Hi10P/Main10 decode)
failed with the hwaccel init error. iter38 5/5 baseline still PASSES
(no regression — non-10-bit path unchanged).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Per Phase 4 plan + Phase 5 review amendments (SPS parse-and-cache,
per-fd gating).
src/h265.c additions:
- #include <errno.h>, the v4l2-hevc-ext-controls.h, and the
vendored gst/codecparsers/gsth265parser.h
- new static helper h265_populate_ext_sps_rps_cache(): walks
surface_object->source_data for an SPS NAL (nal_unit_type == 33)
using gst_h265_parser_identify_nalu; if found, calls
gst_h265_parser_parse_sps_ext (NOT gst_h265_parser_parse_sps —
the latter discards the per-RPS-entry EXT data we need); maps
GstH265ShortTermRefPicSet (base) + GstH265ShortTermRefPicSetExt
(carrying use_delta_flag[16], used_by_curr_pic_flag[16],
delta_poc_s0_minus1[16], delta_poc_s1_minus1[16]) into the V4L2
struct arrays; stores on driver_data->hevc_rps_cache_*
- non-IDR-frame handling: cache holds across frames, so frames
whose source_data lacks an SPS NAL reuse the previously-parsed
cached arrays (Phase 5 review item #3)
- controls[] grows from [5] to [7]; the 2 new entries are appended
after the standard 5 (SPS/PPS/SLICE_PARAMS/SCALING_MATRIX/
DECODE_PARAMS), gated by driver_data->has_hevc_ext_sps_rps_rkvdec
(per-fd probe result from Step 3) + the cache being valid
- field-by-field mapping mirrors GStreamer's
gst_v4l2_codec_h265_dec_fill_ext_sps_rps verbatim (the upstream
reference identified in Phase 0 prior-art survey)
src/request.h additions:
- struct request_data carries hevc_rps_cache_st (array pointer),
_st_count, hevc_rps_cache_lt, _lt_count, hevc_rps_cache_valid.
Single-slot cache (sps_id 0 only; multi-SPS streams would need
expanding). Stores POST-MAPPED V4L2 structs so request.h doesn't
need to know GstH265SPS / GstH265SPSEXT types.
Critical interpretation correction (Phase 5 review followup):
GstH265SPS has short_term_ref_pic_set[65] (base) but NOT
short_term_ref_pic_set_ext[]. The EXT array lives on a SEPARATE
GstH265SPSEXT struct accessed via gst_h265_parser_parse_sps_ext.
The 'plain' gst_h265_parser_parse_sps internally calls _ext with a
LOCAL discarded SPSEXT (see gsth265parser.c:2050). Our call must
use the _ext variant directly to keep the EXT data. Caught during
Step 4 first-build error.
Build verified: ninja -C build clean. .so is 759 KB (up from 485 KB
original, 682 KB after Step 2 vendor — the +80 KB is the new helper
+ extension).
iter2 Phase 6 Step 5 (install + reboot + smoke-test) is the F1
falsifier moment: if HEVC stops OOPSing, mechanism confirmed; if it
still OOPSes, loopback Phase 0 with re-opened kernel-agent#11.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
src/hevc-ctrls/v4l2-hevc-ext-controls.h (NEW, MIT, ~95 LOC):
Verbatim mirror of Linux 7.0 V4L2_CID_STATELESS_HEVC_EXT_SPS_ST_RPS
and _LT_RPS control IDs + struct definitions + flag macros. Each
symbol is ifndef-guarded so when ampere's linux-api-headers
eventually bumps to 7.0+, the kernel header takes precedence and
this shim silently no-ops. Citation block links the upstream
Casanova v8 series.
Per LGPL section 3.b, kernel UAPI struct definitions are excepted
from GPL inheritance, so copying them into MIT userspace is fine.
src/request.h: added has_hevc_ext_sps_rps_rkvdec + _hantro bool
fields on struct request_data — pair-of-flags layout mirrors
video_fd_rkvdec / video_fd_hantro (iter38 multi-device-probe
pattern, per feedback_multi_device_probe_design). Phase 5 review
identified single-scalar storage as a silent-misbehavior risk
across device-switch boundaries.
src/request.c:
- new probe_hevc_ext_sps_rps_controls(fd) helper: queries the two
new CIDs via VIDIOC_QUERYCTRL; returns true iff both register.
RK3399 rkvdec (linux 6.x or 7.x without VDPU381/383 bindings)
returns false; RK3588 rkvdec (VDPU381/383) returns true.
- probe each driver_data->video_fd_rkvdec / _hantro after the
iter38 multi-device-probe block at VA_DRIVER_INIT time
- log-line if rkvdec supports it - diagnostic for Phase 7
src/meson.build: added the new UAPI header to the headers list.
Build verified: ninja -C build clean, .so produced. The new probe
runs at driver init and stores the result, but nothing CONSUMES the
result yet — that's Step 4 (h265_set_controls wiring).
Per ampere-kernel-decoders campaign iter2 Phase 4 step 3 (amended
by Phase 5 review item 'per-fd storage').
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Vendored gsth265parser + nalutils + gstbitreader + gstbytereader (the
Step 1 commit) compile cleanly against libc + libv4l2 only after
adding 1 compat translation unit + 5 stub headers, no edits to the
vendored .c/.h files themselves.
src/h265_parser/gst_compat.{h,c} — new files (MIT, original work):
- GLib type aliases (gboolean, gchar, gint*, guint*, gsize, gpointer)
- Memory helpers (g_malloc/g_free as #define free, g_memdup2 inline)
- Asserts as no-op + parser-return-code-propagation
- All GST_DEBUG/INFO/WARNING/ERROR/LOG/FIXME as no-ops (the parser
is heavy on debug logging; we compile it all out)
- GArray implementation (~100 LOC, just enough for gsth265parser.c's
24 call sites)
- GList full struct with .data/.next/.prev so callers compile;
list-manipulation functions abort() — dead code paths only
- Byte-order read/write macros (GST_READ_UINT8/16/24/32/64_LE/BE,
GST_WRITE_UINT8/16/24/32_BE) — aarch64 LE inlines
- g_once_init_enter/leave as simple gate
- G_MAXUINT*, G_MAXINT*, G_MINxxx, G_GNUC_* attribute macros, etc.
- Opaque GstBuffer/GstMemory/GstMapInfo + abort-stub functions for
the encoder-side SEI-insertion paths the libva backend never invokes
- gst_util_ceil_log2 real impl (used by slice-header parser; dead
for our SPS-only call path but cheaper to implement than stub)
src/h265_parser/gst/{gst.h,base/base-prelude.h,base/gstbitwriter.h,
codecparsers/codecparsers-prelude.h,glib-compat-private.h} — 5 new
stub headers (MIT). All include gst_compat.h. gstbitwriter.h adds
abort-stub functions for the bit-writer API (used by nalutils.c's NAL
emulation-prevention encoder path — dead code for the parse-only
libva backend).
src/meson.build — added the 5 new .c source files and 10 new .h
headers; added include_directories('h265_parser') to the include path
so the vendored files' '#include <gst/base/...>' style references
resolve to the stub headers + actual vendored files in the local
tree.
Build verified: ninja -C build produces v4l2_request_drv_video.so
(682 KB, up from 485 KB pre-vendor — the +200 KB is the vendored
parser code). nm shows gst_h265_parse_sps, gst_h265_parse_sps_ext,
gst_h265_parser_identify_nalu, and the other functions we need for
Step 4 are present in the binary.
Two #warning messages from gsth265parser.h about API stability are
upstream-intentional and harmless ('The H.265 parsing library is
unstable API and may change in future').
This commit completes Step 2 of ampere-kernel-decoders iter2 Phase 6.
Backend remains functionally identical to pre-iter2 — the new code
compiles + links but is not yet called from h265_set_controls (that's
Step 4). Existing 5 codecs continue to work as before.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Source: gitlab.freedesktop.org/gstreamer/gstreamer @ commit 43421c2a5b8a
(refs/tags/1.28.2). All 8 vendored files copied verbatim into
src/h265_parser/:
gst-plugins-bad/gst-libs/gst/codecparsers/gsth265parser.c (168 KB)
gst-plugins-bad/gst-libs/gst/codecparsers/gsth265parser.h ( 92 KB)
gst-plugins-bad/gst-libs/gst/codecparsers/nalutils.c (13 KB)
gst-plugins-bad/gst-libs/gst/codecparsers/nalutils.h ( 8 KB)
gstreamer/libs/gst/base/gstbitreader.c ( 8 KB)
gstreamer/libs/gst/base/gstbitreader.h ( 10 KB)
gstreamer/libs/gst/base/gstbytereader.c ( 39 KB)
gstreamer/libs/gst/base/gstbytereader.h ( 25 KB)
Total ~11 KLOC, LGPL v2.1+ per original headers (Intel + Sreerenj
Balachandran + others). LGPL headers preserved verbatim. Backend's
existing COPYING.LGPL covers redistribution.
** Build is INTENTIONALLY BROKEN at this commit. ** GLib dependencies
(GArray, g_malloc, gboolean, GST_DEBUG, etc.) are not yet satisfied;
src/Makefile.am is not yet updated to include these files. Step 2
performs the GLib-to-libc mechanical adaptation; Step 3 wires the
header + Makefile.
This vendor-unchanged commit is the upstream-tracking baseline. When
GStreamer ships a parser bug fix, the future-sync workflow is:
git diff src/h265_parser/ HEAD..(this commit)
to surface our adaptations, then rebase those over the upstream fix.
Per ampere-kernel-decoders campaign iter2 Phase 4 §Step 1
(/home/mfritsche/src/ampere-kernel-decoders/phase4_plan_iter2.md).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Fixes the rkvdec_hevc_prepare_hw_st_rps out-of-bounds kernel OOPS that
blocked HEVC decode on ampere (RK3588) per
marfrit/libva-v4l2-request-fourier#3 and ampere-fourier iter1 close.
Mechanism (Phase 5 amendment to issue body):
The new EXT_SPS controls are registered as V4L2_CTRL_FLAG_DYNAMIC_ARRAY
in vdpu38x_hevc_ctrl_descs (rkvdec.c:279/284) with cfg.dims = { 65 }.
The v4l2-ctrl framework init-allocates 1 zeroed element (ctrls-core.c:2116).
When num_short_term_ref_pic_sets > 1, rkvdec_hevc_prepare_hw_st_rps
(rkvdec-hevc-common.c:393-405) iterates idx 0..N-1 and overruns the
1-element kernel allocation. Submitting an N-element dynamic-array
control via S_EXT_CTRLS extends the framework allocation.
Userspace fix:
- VIDIOC_QUERY_EXT_CTRL probe at first HEVC CreateContext sets
driver_data->has_ext_sps_rps (true on VDPU381/383, false on legacy
RK3399 — control unregistered there, so fresnel iter38 5/5 + iter39
sub-profile paths are byte-identical to pre-iter2).
- When set, h265_set_controls appends EXT_SPS_ST_RPS + _LT_RPS as
calloc'd zero arrays, sized by VAAPI's count fields and capped at
H.265 §7.4.3.2 spec maxima (ST 64, LT 32). Min 1 (kernel rejects 0).
- Free post-S_EXT_CTRLS.
Decode correctness scope:
VAAPI does NOT expose per-set st_ref_pic_set syntax elements
(delta_idx_minus1, delta_rps_sign, etc.) — confirmed in va_dec_hevc.h.
All-zero entries give empty inter-pred RPS per set, which is correct
for IDR-only streams and incorrect for streams with inter-pred RPS
dependence. iter2 acceptance: stop the OOPS. Decode-correctness for
inter-RPS content is a known follow-up requiring either bitstream-snoop
or SPS-passthrough via a new VAAPI extension.
Files:
- include/hevc-ctrls.h: #ifndef-guarded fallback definitions for
V4L2_CID_STATELESS_HEVC_EXT_SPS_{ST,LT}_RPS + structs (ampere host
is on linux-api-headers 6.19-1; the new CIDs land in 7.0).
- src/request.h: driver_data->has_ext_sps_rps (persists for driver
lifetime; gated solely by HEVC code path so cross-codec leakage
impossible).
- src/context.c: probe at HEVC CreateContext via v4l2_query_ext_ctrl.
- src/h265.c: controls[5] → controls[7]; #include <hevc-ctrls.h>
(replaces <linux/v4l2-controls.h>) for forward UAPI compatibility.
Compile-tested on boltzmann (aarch64 native, gcc 15.2.1): clean .so,
0 new warnings. Fresnel cross-device safety: legacy RK3399 rkvdec_ctrl
table omits the CIDs; probe returns false; new code path never executes.
iter39 sub-profile work (commits 662f887 + 8746690) is preserved
in-tree; iter2 is a forward-compatible additive change.
Refs:
marfrit/libva-v4l2-request-fourier#3
ampere-fourier/iter1_close.md HEVC blocker
ampere-fourier/iter2_phase0_findings.md
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Pure-C unit test for nv15_unpack_plane_to_p010, independent of any V4L2
hardware. Verifies bit layout against the spec at
Documentation/userspace-api/media/v4l/pixfmt-nv15.rst by packing known
10-bit pixel values, running the unpack, and asserting P010 output
matches pixel<<6.
Coverage:
- zero, all-max
- 8 known position/spread vectors
- widths {1, 2, 3, 7, 8} including remainder paths
- multi-row with stride padding
- chroma-shape (half-height)
Build + run:
cc -Wall -Werror -O2 -o test_nv15_unpack \
tests/test_nv15_unpack.c src/nv15.c
./test_nv15_unpack
Confirmed PASS on noether (x86_64 native). Catches the highest-risk
class of regression in iter39 — silent bit-shift errors in the unpack —
without requiring fresnel hardware.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds VAProfileH264High10 and VAProfileHEVCMain10 to the libva-v4l2-request
backend. RK3399 rkvdec emits decoded frames as V4L2_PIX_FMT_NV15 (4 × 10-bit
values packed in 5 bytes per element); VAAPI consumers receive standard
VA_FOURCC_P010 via a new userspace unpack in copy_surface_to_image.
VP9 Profile 2 explicitly NOT added — RK3399 rkvdec kernel ctrl table
caps at V4L2_MPEG_VIDEO_VP9_PROFILE_0 (rkvdec.c::rkvdec_vp9_ctrl_descs).
Touchpoints (per Phase 5 sonnet-architect review amendments):
- include/drm_fourcc.h: define DRM_FORMAT_NV15 (vendored libdrm lacks it)
- src/nv15.{c,h}: NV15 → P010 plane unpack (LSB-first, per
Documentation/userspace-api/media/v4l/pixfmt-nv15.rst)
- src/video.c: NV15 entry in formats[] (else NULL-deref on video_format_find)
- src/codec.c: pixelformat_for_profile cases for Hi10P + Main10
- src/config.c: enumeration, validation, entrypoints, RT_FORMAT_YUV420_10
advertisement for 10-bit profiles
- src/context.c: per-profile CAPTURE pix_fmt (NV12/NV15), 10-bit synthetic
SPS (bit_depth_luma_minus8=2), video_format invalidation on bit-depth
transition (sibling to iter38 device-switch invalidation), is_10bit flag
- src/surface.c: RT_FORMAT_YUV420_10 admission, NV15 fourcc on PRIME export
- src/image.c: P010 reporting in DeriveImage + QueryImageFormats,
P010-aware sizing in CreateImage, NV15 → P010 unpack call in
copy_surface_to_image (gated on is_10bit + image.format.fourcc == P010)
- src/picture.c: 4 switch blocks route Hi10P/Main10 to existing H264/HEVC
per-codec paths
- src/request.h: MAX_PROFILES bump 11 → 13, driver_data->is_10bit flag
Scope: COPY path (vaGetImage / vaDeriveImage) only. Standard ffmpeg-vaapi
hwdownload, mpv vaapi-copy, and any consumer using vaGetImage works
end-to-end. PRIME-path consumers that only know NV12/P010 must use the
COPY path; PRIME consumers aware of NV15 (panfrost-Mesa et al.) get the
correct fourcc on RequestExportSurfaceHandle. PRIME-side P010 emission is
follow-up scope (would need DRM_FORMAT_P010 + per-plane unpack into a
GPU-accessible buffer).
Compile-tested on boltzmann (aarch64 native, gcc 15.2.1, libva 1.23.0,
libdrm 2.4.133): clean build, .so produced, 0 new warnings.
Phase 0/2 evidence: linux-mmind-v7.0 drivers/media/platform/rockchip/rkvdec.
rkvdec_h264_decoded_fmts[] and rkvdec_hevc_decoded_fmts[] both list NV15;
ctrl tables cap at HEVC MAIN_10 and H264 HIGH_422_INTRA (Hi10P < cap, not
in menu_skip_mask). image_fmt resolution (rkvdec-h264-common.c:196,
rkvdec-hevc-common.c:467) dispatches on bit_depth_luma_minus8 only.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Latent bug surfaced by iter38 multi-device probe. profiles[] array
in RequestQueryConfigProfiles is sized by V4L2_REQUEST_MAX_PROFILES
(set as context->max_profiles=11 in VA_DRIVER_INIT), but the bounds
checks used V4L2_REQUEST_MAX_CONFIG_ATTRIBUTES (10). Pre-iter38 only
a single device's profiles were enumerated, total ≤9, so the off-by-
one never bit. With iter38's rkvdec+hantro union (10 profiles total
across MPEG2/H264/HEVC/VP8/VP9), the last enumerator (VP9) hit
index=9 with the check 'index < 10-1 = 9' → skipped.
Probe BOTH rkvdec and hantro-vpu at VA_DRIVER_INIT and keep their
{video,media}_fd pairs in driver_data. RequestQueryConfigProfiles
enumerates the union of supported profiles from all open fds.
RequestCreateConfig retargets driver_data->{video,media}_fd to the
device that serves the requested profile; if a switch is needed
(active fd is wrong), tears down output_pool, capture_pool, video_format
cache, and fmt_valid so the next RequestCreateContext rebuilds them
on the new device.
Profile→device map (RK3399-shaped):
H264 / HEVC / VP9 → rkvdec
MPEG-2 / VP8 → hantro-vpu
Honours LIBVA_V4L2_REQUEST_VIDEO_PATH / MEDIA_PATH explicit overrides
(skips alt-probe when those are set).
Closes the 'libva multi-device probe' open item from iter36/iter37
campaign-close.
α-26 (iter26) wrote VAAPI's picture->st_rps_bits to the V4L2 decode_params
field of the same name based on field-name match. Per V4L2 spec, this field
is the bit-count of st_ref_pic_set() *in the SPS* — VAAPI doesn't expose
that. The slice-header bit-count (which IS what VAAPI's st_rps_bits provides)
belongs in slice_params->short_term_ref_pic_set_size (handled correctly in
α-29).
rkvdec doesn't read decode_params->short_term_ref_pic_set_size, so the
misroute was harmless but stale. This revert restores spec-correct semantics
(0 when SPS bit-count is unknown).
Cosmetic cleanup; no functional change.
ROOT CAUSE FIX for VP8 libva decode garbage output.
ffmpeg-vaapi's vaapi_vp8.c:191-192 STRIPS the VP8 uncompressed
header (3 bytes for interframe, 10 bytes for keyframe) before
submitting the slice data via VAAPI. ffmpeg-v4l2request (kdirect)
KEEPS the header in its OUTPUT buffer.
Hantro's rockchip_vpu2_vp8_dec_run (rockchip_vpu2_hw_vp8_dec.c:349)
hard-codes 'first_part_offset = V4L2_VP8_FRAME_IS_KEY_FRAME(hdr) ? 10 : 3'
as the byte offset into OUTPUT where the first compressed partition
starts. It uses this offset for:
- mb_offset_bits = first_part_offset * 8 + first_part_header_bits + 8
- dct_part_offset = first_part_offset + first_part_size
Without the header, every offset is wrong, the entropy decoder
spins on the wrong bytes, and every frame decodes to garbage.
Fix: in codec_store_buffer for VAProfileVP8Version0_3, prepend
header_size bytes (10 keyframe / 3 interframe) of zeros to OUTPUT
before the slice data memcpy. Hantro skips these bytes for actual
parsing (uses ctrl-struct values instead), so zero-fill is fine.
Empirical: iter33 kernel printk in vpu2_vp8_dec_run dumped the
v4l2_ctrl_vp8_frame struct for libva vs kdirect and confirmed
byte-identical control fields. Only the OUTPUT buffer bytes
differed, traced to ffmpeg-vaapi's header stripping.
LIBVA_VP8_DUMP_FRAME=1 prints the v4l2_ctrl_vp8_frame struct fields
to stderr before VIDIOC_S_EXT_CTRLS. Goal: diff libva-side struct
against expected kdirect-side values for VP8 frame-2+ divergence
(libva produces non-trivial but wrong output; kdirect VP8 byte-equal
to SW). Env-gated, no behavior change otherwise.
ROOT CAUSE FIX for HEVC frame 2+ divergence (Bug 5 remainder).
rkvdec's assemble_sw_rps (rkvdec-hevc.c:386-389) uses
sl_params->short_term_ref_pic_set_size to compute the bit offset where
long-term RPS data starts in the slice header. When zero, it falls back
to fls(num_short_term_ref_pic_sets - 1) — wrong when num=1 (BBB's case).
α-26 misdirected: set decode_params->short_term_ref_pic_set_size = st_rps_bits
but rkvdec doesn't use that field. The correct consumer is slice_params per
V4L2 spec and rkvdec source.
VAAPI's picture->st_rps_bits is documented as: 'number of bits that structure
short_term_ref_pic_set(num_short_term_ref_pic_sets) takes in slice segment
header when short_term_ref_pic_set_sps_flag equals 0' — exactly what
sl_params->short_term_ref_pic_set_size means.
Frames 1 (IDR) unaffected (V4L2 rkvdec gates on !IDR_PIC flag).
Frames 2+: bit offset for long-term RPS now correct, slice header parsing
no longer falls off the edge of the entropy bitstream.
Default behavior unchanged: counter*1000ns same as before.
With LIBVA_TS_SCALE=N, multiplies the ns timestamp by N. Lets us
sweep timestamp magnitude to test whether small-ts collides with
stale CAPTURE entries in vb2_find_buffer for HEVC frame 2+ bug.
Also keeps iter29 slice-tail probe from previous commit.
Env-gated via LIBVA_HEVC_DUMP_SLICE_TAIL=1. Goal: characterise the
40-byte inflation in libva's slice_data buffer vs ffmpeg-v4l2request
(see iter27/28 close — HEVC frame 2+ divergence at byte 1382401).
Dumps per slice: nal_unit_type, slice_data_size, slice_data_byte_offset,
and the last 80 bytes of source_data for that slice. Lets us see if the
trailing 40 bytes are (a) real entropy, (b) trailing zeros, (c) a
next-NAL start code prefix, or (d) random memory.
iter28b tested LIBVA_HEVC_TRIM_TRAILING=40 on HEVC. Result: hash
differed at byte 899745 (inside frame 1, NOT just frame 2 boundary at
byte 1382401). Trimming 40 bytes off the IDR slice (96890→96850)
corrupted frame 1. The 40-byte inflation is not uniform per slice;
requires dynamic detection (e.g., scan for rbsp_stop_one_bit) or
per-slice-type logic.
VAAPI's slice_data_size includes NAL+slice header bytes that precede the
slice payload. rkvdec_hevc expects bit_size to cover the slice payload
(starting at data_byte_offset). Setting bit_size = slice_data_size * 8
made rkvdec read past slice payload → wrong entropy state → frame 2+
garbage despite correct ctx->image_fmt (iter25) and decode_params
(iter26).
Empirical match: with formula (slice_data_size - slice_data_byte_offset)
* 8, libva produces bit_size=44096 for BBB frame 2 matching kdirect's
44096 exactly per iter27 dmesg printk.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
VAPictureParameterBufferHEVC exposes st_rps_bits — the number of bits
the inline short_term_ref_pic_set syntax element takes in the slice
header. rkvdec's DPB resolution for P/B frames uses this to skip the
RPS data correctly; with size=0 it skips wrong bytes and reads wrong
references → frame 2+ visual divergence.
iter25 evidence: libva HEVC frame 1 byte-identical to kdirect, but
frame 2 diverges at the decode_params bytes 4-5 (libva 0x00 0x00,
kdirect 0x0a 0x00 = 10).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
rkvdec_h264_validate_sps doubles height when FRAME_MBS_ONLY is unset
(field-to-frame). Dummy with 1080-height was failing validation as
2176 > 1080, returning -EINVAL silently (void-cast). Even though libva
ignores the result of v4l2_set_controls, the side effect was leaving
ctx->image_fmt at ANY → first per-frame H264_SPS still hit -EBUSY in
try_or_set_cluster → setup loop broke (Bug 4 unchanged).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Root cause for Bug 5 (HEVC libva = all-zero CAPTURE) and Bug 4 (H.264
libva = keyframe partial), localized via iter17→iter24 kernel-printk
chain:
rkvdec_s_ctrl() for HEVC_SPS / H264_SPS calls get_image_fmt() and,
if the resolved image_fmt differs from cached ctx->image_fmt (default
RKVDEC_IMG_FMT_ANY at open), tries to reset the CAPTURE format.
Format reset returns -EBUSY when vb2_is_busy(CAPTURE_queue) — any
CAPTURE buffer allocated blocks the change.
libva (iter5b-β) pre-allocates 24 CAPTURE buffers at CreateContext
via cap_pool_init, BEFORE any per-frame S_EXT_CTRLS. First per-frame
HEVC_SPS therefore fails with -EBUSY in try_or_set_cluster, breaks
v4l2_ctrl_request_setup's outer loop, leaves all 5 staged HEVC
compound controls at zero in ctx->ctrl_hdl. rkvdec_hevc_run reads
zero (iter20 dmesg: sps[0..16]=00..00), hardware sees w=0 h=0,
CAPTURE comes out all-zero (Bug 5).
Fix: BEFORE cap_pool_init, inject one S_EXT_CTRLS (no request, no
which) with a synthetic SPS containing the profile's known chroma +
bit_depth. CAPTURE queue is still empty at this point → vb2_is_busy
returns false → rkvdec_s_ctrl succeeds, ctx->image_fmt is updated to
the profile's image_fmt. From then on, per-frame SPS submissions with
matching chroma + bit_depth see image_fmt_changed=false → skip reset
→ commit succeeds.
VP9 / MPEG-2 / VP8 paths are not affected: VP9's rkvdec coded_fmt_desc
has no get_image_fmt op; MPEG-2 + VP8 route to hantro.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
marfrit
claude-noether