Dne petek, 15. julij 2022 ob 17:36:01 CEST je Nicolas Dufresne napisal(a): > Le vendredi 15 juillet 2022 à 12:04 +0100, Robin Murphy a écrit : > > On 2022-07-13 17:24, Sebastian Fricke wrote: > > > Implement the HEVC codec variation for the RkVDEC driver. Currently only > > > the RK3399 is supported, but it is possible to enable the RK3288 as it > > > also supports this codec. > > > > > > Based on top of the media tree @ef7fcbbb9eabbe86d2287484bf366dd1821cc6b8 > > > and the HEVC uABI MR by Benjamin Gaignard. > > > (https://patchwork.linuxtv.org/project/linux-media/list/?series=8360) > > > > > > Tested with the GStreamer V4L2 HEVC plugin: > > > (https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/107 > > > 9) > > > > > > Current Fluster score: > > > `Ran 131/147 tests successfully in 278.568 secs` > > > with > > > `python3 fluster.py run -d GStreamer-H.265-V4L2SL-Gst1.0 -ts > > > JCT-VC-HEVC_V1 -j1` > > > > > > failed conformance tests: > > > - DBLK_D_VIXS_2 (Success on Hantro G2) > > > - DSLICE_A_HHI_5 (Success on Hantro G2) > > > - EXT_A_ericsson_4 (Success on Hantro G2) > > > - PICSIZE_A_Bossen_1 (Hardware limitation) > > > - PICSIZE_B_Bossen_1 (Hardware limitation) > > > - PICSIZE_C_Bossen_1 (Hardware limitation) > > > - PICSIZE_D_Bossen_1 (Hardware limitation) > > > - PPS_A_qualcomm_7 (Success on Hantro G2) > > > - SAODBLK_A_MainConcept_4 (Success on Hantro G2) > > > - SAODBLK_B_MainConcept_4 (Success on Hantro G2) > > > - SLIST_B_Sony_9 (Success on Hantro G2) > > > - SLIST_D_Sony_9 (Success on Hantro G2) > > > - TSUNEQBD_A_MAIN10_Technicolor_2 (Success on Hantro G2) > > > - VPSSPSPPS_A_MainConcept_1 (Success on Hantro G2) > > > - WPP_D_ericsson_MAIN10_2 (Fail on Hantro G2) > > > - WPP_D_ericsson_MAIN_2 (Fail on Hantro G2) > > > > > > Not tested with FFMpeg so far. > > > > > > Known issues: > > > - Unable to reliably decode multiple videos concurrently > > > - The SAODBLK_* tests timeout if the timeout time in fluster is lower > > > than 120 - Currently the uv_virstride is calculated in a manner that is > > > hardcoded for the two available formats NV12 and NV15. > > > (@config_registers) > > > > > > Notable design decisions: > > > - I opted for a bitfield to represent the PPS memory blob as it is the > > > perfect tool for that job. It describes the memory layout with any > > > additional required documentation, is easy to read and a native language > > > tool for that job > > > > Can I point out how terrible an idea this is? The C language gives > > virtually zero guarantee about how bitfields are actually represented in > > memory. Platform ABIs (e.g. [1]) might nail things down a bit more, but > > different platforms are free to make completely different choices so > > portability still goes out the window. Even for a single platform, > > different compilers (or at worst even different version of one compiler) > > can still make incompatible choices e.g. WRT alignment of packed > > members. Even if you narrow the scope as far as a specific version of > > AArch64 GCC, I think this is still totally broken for big-endian. > > > > The fact that you've had to use nonsensical types to trick a compiler > > into meeting your expectations should already be a clue to how fragile > > this is in general. > > > > > - The RPS memory blob is created using a bitmap implementation, which > > > uses a common Kernel API to avoid reinventing the wheel and to keep the > > > code clean. > > > > Similarly, Linux bitmaps are designed for use as, well, bitmaps. Abusing > > them as a data interchange format for bit-aligned numerical values is > > far from "clean" semantically. And I'm pretty sure it's also broken for > > big-endian. > > > > This kind of stuff may be standard practice in embedded development > > where you're targeting a specific MCU with a specific toolchain, but I > > don't believe it's suitable for upstream Linux. It would take pretty > > much the same number of lines to use GENMASK definitions and bitfield.h > > helpers to pack values into words which can then be written to memory in > > a guaranteed format and endianness (certainly for the PPS; for the RPS > > it may well end up a bit longer, but would be self-documenting and > > certainly more readable than those loops). It mostly just means that for > > any field which crosses a word boundary you'll end up with 2 definitions > > and 2 assignments, which is hardly a problem (and in some ways more > > honest about what's actually going on). > > Thanks for the feedback, in multimedia (unlike register programming), we > don't really consider bitstreams as bitmap or bitfield. What we do really > expect is to use bit writer helpers (and sometimes a bit reader though we > try and avoid the second one in the kernel). Its more of less a cursor (a > bit position) into a memory that advance while writing. A bit writer should > help protect against overflow too. > > When writing lets say a chain of 8 bits from a char, a proper helper is > expected to be very explicit on the ordering (write_u8_le/be or something > better worded). I would rather like to see all these blobs written this way > personally then having a cleared buffer and writing using bit offsets. > > Perhaps I may suggest to start with implementing just that inside this > driver? It isn't very hard, and then the implementation can be reduced > later and shared later, with whatever exists without deviating from the > intent of the existing API ? I do believe that having this in linux-media > can be useful in the future. We will notably need to extend such a helper > with multimedia specific coding technique (golomb, boolean coding, etc.) > for use in stateless encoder drivers. I don't know RKVDEC, but at least Cedar has integrated bitstream parsing engine. Is there something similar in RKVDEC? That way HW could be used instead of SW implementation. Best regards, Jernej > > Nicolas > > > Thanks, > > Robin. > > > > [1] > > https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst#bit-f > > ields> > > > - I deliberatly opted against the macro solution used in H264, which > > > declares Macros in mid function and declares the fields of the memory > > > blob as macros as well. And I would be glad to refactor the H264 code if > > > desired by the maintainer to use common Kernel APIs and native language > > > elements. > > > - The giant static array of cabac values is moved to a separate c file, > > > I did so because a separate .h file would be incorrect as it doesn't > > > expose anything of any value for any other file than the rkvdec-hevc.c > > > > > > file. Other options were: > > > - Calculating the values instead of storing the results (doesn't seem > > > to be worth it) > > > - Supply them via firmware (Adding firmware makes the whole software > > > way more complicated and the usage of the driver less obvious) > > > > > > Ignored Checkpatch warnings (as it fits to the current style of the > > > file): > > > ``` > > > WARNING: line length of 162 exceeds 100 columns > > > #115: FILE: drivers/media/v4l2-core/v4l2-common.c:265: > > > + { .format = V4L2_PIX_FMT_NV15, .pixel_enc = > > > V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 5, 5, > > > 0, 0 }, .hdiv = 2, .vdiv = 2, > > > > > > ERROR: trailing statements should be on next line > > > #128: FILE: drivers/media/v4l2-core/v4l2-ioctl.c:1305: > > > + case V4L2_PIX_FMT_NV15: descr = "10-bit Y/CbCr 4:2:0 > > > (Packed)"; break; ``` > > > > > > v4l2-compliance test: > > > ``` > > > Total for rkvdec device /dev/video3: 46, Succeeded: 46, Failed: 0, > > > Warnings: 0 ``` > > > > > > kselftest module run for the bitmap changes: > > > ``` > > > $ sudo insmod > > > /usr/lib/modules/5.19.0-rc3-finalseries/kernel/lib/test_bitmap.ko [ > > > 71.751716] test_bitmap: parselist: 14: input is '0-2047:128/256' OK, > > > Time: 1750 [ 71.751787] test_bitmap: bitmap_print_to_pagebuf: input > > > is '0-32767 [ 71.751787] ', Time: 6708 > > > [ 71.760373] test_bitmap: set_value: 6/6 tests correct > > > ``` > > > > > > Jonas Karlman (2): > > > media: v4l2: Add NV15 pixel format > > > media: v4l2-common: Add helpers to calculate bytesperline and > > > > > > sizeimage > > > > > > Sebastian Fricke (4): > > > bitops: bitmap helper to set variable length values > > > staging: media: rkvdec: Add valid pixel format check > > > staging: media: rkvdec: Enable S_CTRL IOCTL > > > staging: media: rkvdec: Add HEVC backend > > > > > > .../media/v4l/pixfmt-yuv-planar.rst | 53 + > > > drivers/media/v4l2-core/v4l2-common.c | 79 +- > > > drivers/media/v4l2-core/v4l2-ioctl.c | 1 + > > > drivers/staging/media/rkvdec/Makefile | 2 +- > > > drivers/staging/media/rkvdec/TODO | 22 +- > > > .../staging/media/rkvdec/rkvdec-hevc-data.c | 1844 +++++++++++++++++ > > > drivers/staging/media/rkvdec/rkvdec-hevc.c | 859 ++++++++ > > > drivers/staging/media/rkvdec/rkvdec-regs.h | 1 + > > > drivers/staging/media/rkvdec/rkvdec.c | 182 +- > > > drivers/staging/media/rkvdec/rkvdec.h | 3 + > > > include/linux/bitmap.h | 39 + > > > include/uapi/linux/videodev2.h | 1 + > > > lib/test_bitmap.c | 47 + > > > 13 files changed, 3066 insertions(+), 67 deletions(-) > > > create mode 100644 drivers/staging/media/rkvdec/rkvdec-hevc-data.c > > > create mode 100644 drivers/staging/media/rkvdec/rkvdec-hevc.c
