VAAPI signals "explicit scaling lists are present in the bitstream"
implicitly: the consumer (ffmpeg-vaapi, mpv, etc.) sends a
VAIQMatrixBufferH264 alongside RenderPicture iff
sps_scaling_matrix_present_flag || pps_scaling_matrix_present_flag.
When the bitstream uses default (flat) scaling, no IQMatrixBuffer
arrives and the in-tree h264.matrix struct stays zero-initialised.
fourier's existing codec_store_buffer for MPEG2 and HEVC tracks this
via a per-surface iqmatrix_set boolean (surface.h::mpeg2.iqmatrix_set,
h265.iqmatrix_set) — the H.264 path was missing the equivalent flag,
so set_controls always submitted the scaling matrix, including the
zero-initialised case.
Symptom on hantro-vpu RK3568: when TRANSFORM_8X8_MODE is enabled in
PPS, the kernel multiplies all 8x8 DCT coefficients by the zeroed
scaling_list_8x8, producing a zeroed CAPTURE buffer despite a
successful decode round-trip (no V4L2_BUF_FLAG_ERROR,
bytesused=3655712 reported).
Earlier draft of this patch unconditionally omitted SCALING_MATRIX in
FRAME_BASED. That's corpus-correct (bbb has no explicit scaling
lists) but the wrong predicate: the kernel-side gating is by
"matrix-supplied vs. not," not by decode mode. Streams that signal
explicit scaling lists must submit SCALING_MATRIX in either mode.
Contract verification (audit_0008_decode_params_2026-05-01.md +
hantro_h264.c::assemble_scaling_list): the kernel uses the supplied
matrix when SCALING_MATRIX is in the control batch and falls back
to spec-defined defaults when absent. Mode-independent.
This patch:
- surface.h: adds bool matrix_set to params.h264, mirroring
mpeg2.iqmatrix_set / h265.iqmatrix_set.
- picture.c codec_store_buffer (H.264 VAIQMatrixBufferType case):
sets matrix_set = true when the buffer arrives.
- picture.c RequestBeginPicture: resets matrix_set = false at the
start of each Begin/Render/End cycle.
- h264.c h264_set_controls: builds the controls[] array
incrementally; SPS/PPS/DECODE_PARAMS always; SCALING_MATRIX iff
matrix_set; SLICE_PARAMS only in SLICE_BASED; PRED_WEIGHTS only
when both SLICE_BASED and V4L2_H264_CTRL_PRED_WEIGHTS_REQUIRED.
The pre-existing FRAME_BASED-omits-SLICE_PARAMS rule is preserved —
kernel doc ext-ctrls-codec-stateless.rst:752: "When this mode is
selected, the V4L2_CID_STATELESS_H264_SLICE_PARAMS control shall
not be set."
Cross-reference: kernel UAPI section
ext-ctrls-codec-stateless.rst V4L2_CID_STATELESS_H264_SCALING_MATRIX
(matrix supplied iff explicit scaling lists in bitstream) and
hantro_h264.c::assemble_scaling_list (consumes supplied matrix or
falls back to defaults).
Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>
Diagnostic-only. Writes 0xab×32 into the CAPTURE buffer's first 32
bytes immediately before VIDIOC_QBUF. The 0010 hex-dump after
DQBUF reveals which case we're in:
- All 0xab → kernel never wrote to this buffer (wrong buffer
chosen, alias, or no decode actually happened despite
bytesused=3655712 reported).
- All zeros → kernel did write 0x00s (overwriting our
sentinel), and the apparent "no picture" output is the
kernel-side decode actually producing zeros (e.g. parser
rejected the bitstream).
- Mix of zeros and real luma values → kernel wrote real
decoded pixels; CPU read sees stale-cached zeros somewhere
OR the sentinel area was a header that decoder zeroed but
rest is real. Need to check more bytes.
- All 0xab still → kernel never touched this region but other
parts of buffer may be filled (incomplete decode).
Removed once Step 1 decode is verified.
Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>
Diagnostic-only patch (NOT for upstream). Hex-dumps:
- First 32 bytes of OUTPUT buffer at QBUF time in
picture.c::RequestEndPicture (i.e. what we feed the kernel)
- First 32 bytes of CAPTURE Y-plane after DQBUF in
surface.c::RequestSyncSurface (i.e. what kernel returned)
Lets us see whether:
- OUTPUT bitstream begins with valid ANNEX_B start code + NAL
header byte (e.g. `00 00 01 65` for IDR slice)
- CAPTURE Y-plane after decode contains varied luma data
(working) vs. all-zeros / repeating pattern (kernel didn't
write anything).
Removed once Step 1 decode is verified working. Output goes via
existing request_log() to stderr.
Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>
Commit 3 of the upstreamable plan (upstreamable_design.md §1, §5).
Replaces the prior per-surface OUTPUT-buffer ownership model with a
small driver-wide pool sized by codec pipeline depth (4 H.264 frames
in flight), allocated unconditionally regardless of caller's
num_render_targets.
Prior art (kernel UAPI dev-stateless-decoder.rst, ffmpeg
v4l2_request.c, Chromium V4L2StatelessVideoDecoder, GStreamer
v4l2slh264dec) all decouple OUTPUT and CAPTURE pool sizing. fourier's
"output_count == surfaces_count" model was a category error: OUTPUT
buffers are request-time bitstream slots, CAPTURE buffers are
picture-time DPB slots; their lifecycles and sizing are independent.
Changes:
* NEW src/request_pool.{c,h} (~200 LoC):
- request_pool_init(): CREATE_BUFS + per-slot QUERYBUF + mmap.
- request_pool_destroy(): munmap all, idempotent.
- request_pool_acquire(): round-robin claim; returns V4L2 buffer
index of an unused slot or -1.
- request_pool_release(): mark slot free for reuse.
- request_pool_slot(): accessor for ptr/size given a buffer index.
* src/request.h: add struct request_pool output_pool to request_data.
* src/context.c::RequestCreateContext: replace the per-surface
OUTPUT loop with a single request_pool_init() call (count=4,
independent of surfaces_count). Drop the now-unused locals
(length, offset, source_data, output_buffers_count, index,
index_base, i, surface_object). DELETES patch 0002's
"output_buffers_count = ... ? ... : 4" hack inline — the pool's
own count parameter supersedes it.
* src/picture.c::RequestBeginPicture: borrow a pool slot at frame
start, write its mmap pointer/size/index into the surface's
transient source_* fields. The fields stay (still useful as
a borrow handle that the existing codec_store_buffer memcpys
target), but no longer represent surface-permanent ownership.
Reset slices_size/slices_count here too (was implicit on first
Render).
* src/surface.c::RequestSyncSurface: after VIDIOC_DQBUF returns
the OUTPUT buffer, release the pool slot and clear the surface's
borrow handle. Fixes the segv on second-frame submission.
* src/surface.c::RequestDestroySurfaces: remove the munmap of
source_data — pool owns the mmap.
* src/request.c::RequestTerminate: call request_pool_destroy()
before close(video_fd) so munmaps still target a valid fd.
* src/meson.build: add request_pool.c and request_pool.h to the
sources/headers lists.
This commit removes 0002's OUTPUT-pool hack inline (the
"floor to 4" line is gone). The DECODE_MODE/START_CODE block in 0002
remains until commit 4 lands.
Build-verified clean on aarch64.
Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>
Compound patch carrying the fork's pre-Step-1 substrate, originally
authored by Jernej Škrabec / fourier on top of bootlin's a3c2476:
- src/h264.c + src/picture.c: V4L2_CID_MPEG_VIDEO_H264_* renamed to
V4L2_CID_STATELESS_H264_*, struct shapes tracked to mainline
(V4L2_CID_STATELESS_H264_DECODE_MODE/_START_CODE added to the
passthrough shim).
- include/hevc-ctrls.h: redirect shim to <linux/v4l2-controls.h>
(kernel-side HEVC controls now live in the canonical UAPI header).
- src/meson.build: src/h265.c / src/h265.h commented out — HEVC
build path is excluded from this fork (RK3568 hantro G1/G2 has
no HEVC, and the kernel-side HEVC controls have a separate
rework in flight upstream).
- src/tiled_yuv.S: aarch64 stub for tiled_to_planar (assembly
source was sunxi-cedrus armv7-only; aarch64 needs a stub to keep
the build linking).
- include/h264-ctrls.h: removed (dead post-fourier — no source
includes it; the passthrough shim's CID aliases live in the
kernel header now).
Functionally equivalent to the prior fork master commits:
c1f5108 V4L2_PIX_FMT_H264_SLICE rename
4ccbfe9 Strip HEVC build path
da9f2a5 include/h264-ctrls.h passthrough + CID aliases
fc4bb10 src/h264.c track upstream UAPI shape
13e9b64 src/h264.c drop num_slices field
4d14ffb src/tiled_yuv.S aarch64 stub
1b02c9b src/h264.c include utils.h
Folded into one commit during 2026-05-04 Step 1 reconciliation
(see ../phase0_evidence/2026-05-04/findings.md). Per-patch history
of the early fork commits preserved on the pre-step1 branch.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Reference frames are now identified using their timestamp:
set the timestamp when queuing the output buffer and use it to identify
the frame later on.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Drop the per-codec options while at it, since we'll soon include a copy
of the associated headers.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
H.264 and H.265 support is still not supported upstream,
so it makes sense to autodetect each codec and only
enable those that are supported.
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
This adds support for MPEG2 quantization matrices, which are optional
given that fallback default matrices are used (on the kernel side) when
no such matrix is provided.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
void * can be assigned from and stored to any pointer type without any
warning. Remove the explicit casts.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The cedrus_data structure carries the old name. In order to migrate to the
new name, let's rename it to request_data.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The sunxi_cedrus.h header contains a bunch of defines prefixed with
SUNXI_CEDRUS.
As part as the ongoing migration to a more generic name, change that prefix
for V4L2_REQUEST, and the header file to request.h
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
As part of our renaming effort, Rename the libva hooks names to mention
request instead of SunxiCedrus
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The num_slices parameter was improperly set to the number of reference
frames, which is incorrect.
Add a counter for the number of slices per surface, and set num_slices to
that value.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Some functions setting the controls will need the context in the future.
Make sure that we provide it as an argument.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The coding style has been a bit erratic. Enforce the linux kernel coding
style by reusing their .clang-format file, running clang-format on the
source, and ignoring the few shortcomings that clang-format has at the
moment (especially on aligning the define values).
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
This long structure name makes it quite difficult to fit within the 80
characters limit. Shorten it.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The BUFFER macro takes an implicit driver_data argument. In order to make
it obvious that we need it, let's put it as an explicit parameter.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
The libVA API expects rendering to be done after calling EndPicture.
Since SyncSurface calls are generally not issued in a way compatible
with dequeuing buffers (they might be called too early or too late),
always call SyncSurface from EndPicture.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
test0r
Paul Kocialkowski