From 624922a2739b96b83aaf1655d0519b41d30140f7 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Sat, 4 Apr 2020 00:13:41 +0200 Subject: media: v4l2-core: Add helpers to build the H264 P/B0/B1 reflists Building those list is a standard procedure described in section '8.2.4 Decoding process for reference picture lists construction' of the H264 specification. We already have 2 drivers needing the same logic (hantro and rkvdec) and I suspect we will soon have more. Let's provide generic helpers to create those lists. Signed-off-by: Boris Brezillon Signed-off-by: Ezequiel Garcia Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/Kconfig | 4 + drivers/media/v4l2-core/Makefile | 1 + drivers/media/v4l2-core/v4l2-h264.c | 270 ++++++++++++++++++++++++++++++++++++ 3 files changed, 275 insertions(+) create mode 100644 drivers/media/v4l2-core/v4l2-h264.c (limited to 'drivers/media') diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig index 3fa75352d04c..bf49f83cb86f 100644 --- a/drivers/media/v4l2-core/Kconfig +++ b/drivers/media/v4l2-core/Kconfig @@ -48,6 +48,10 @@ config VIDEO_TUNER config V4L2_JPEG_HELPER tristate +# Used by drivers that need v4l2-h264.ko +config V4L2_H264 + tristate + # Used by drivers that need v4l2-mem2mem.ko config V4L2_MEM2MEM_DEV tristate diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile index 144564656d22..2ef0c7c958a2 100644 --- a/drivers/media/v4l2-core/Makefile +++ b/drivers/media/v4l2-core/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_V4L2) += v4l2-dv-timings.o obj-$(CONFIG_VIDEO_TUNER) += tuner.o obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o +obj-$(CONFIG_V4L2_H264) += v4l2-h264.o obj-$(CONFIG_V4L2_FLASH_LED_CLASS) += v4l2-flash-led-class.o diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c new file mode 100644 index 000000000000..edf6225f0522 --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-h264.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * V4L2 H264 helpers. + * + * Copyright (C) 2019 Collabora, Ltd. + * + * Author: Boris Brezillon + */ + +#include +#include + +#include + +/** + * v4l2_h264_init_reflist_builder() - Initialize a P/B0/B1 reference list + * builder + * + * @b: the builder context to initialize + * @dec_params: decode parameters control + * @slice_params: first slice parameters control + * @sps: SPS control + * @dpb: DPB to use when creating the reference list + */ +void +v4l2_h264_init_reflist_builder(struct v4l2_h264_reflist_builder *b, + const struct v4l2_ctrl_h264_decode_params *dec_params, + const struct v4l2_ctrl_h264_slice_params *slice_params, + const struct v4l2_ctrl_h264_sps *sps, + const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES]) +{ + int cur_frame_num, max_frame_num; + unsigned int i; + + max_frame_num = 1 << (sps->log2_max_frame_num_minus4 + 4); + cur_frame_num = slice_params->frame_num; + + memset(b, 0, sizeof(*b)); + if (!(slice_params->flags & V4L2_H264_SLICE_FLAG_FIELD_PIC)) + b->cur_pic_order_count = min(dec_params->bottom_field_order_cnt, + dec_params->top_field_order_cnt); + else if (slice_params->flags & V4L2_H264_SLICE_FLAG_BOTTOM_FIELD) + b->cur_pic_order_count = dec_params->bottom_field_order_cnt; + else + b->cur_pic_order_count = dec_params->top_field_order_cnt; + + for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) { + u32 pic_order_count; + + if (!(dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE)) + continue; + + b->refs[i].pic_num = dpb[i].pic_num; + if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM) + b->refs[i].longterm = true; + + /* + * Handle frame_num wraparound as described in section + * '8.2.4.1 Decoding process for picture numbers' of the spec. + * TODO: This logic will have to be adjusted when we start + * supporting interlaced content. + */ + if (dpb[i].frame_num > cur_frame_num) + b->refs[i].frame_num = (int)dpb[i].frame_num - + max_frame_num; + else + b->refs[i].frame_num = dpb[i].frame_num; + + if (!(dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_FIELD)) + pic_order_count = min(dpb[i].top_field_order_cnt, + dpb[i].bottom_field_order_cnt); + else if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_BOTTOM_FIELD) + pic_order_count = dpb[i].bottom_field_order_cnt; + else + pic_order_count = dpb[i].top_field_order_cnt; + + b->refs[i].pic_order_count = pic_order_count; + b->unordered_reflist[b->num_valid] = i; + b->num_valid++; + } + + for (i = b->num_valid; i < ARRAY_SIZE(b->unordered_reflist); i++) + b->unordered_reflist[i] = i; +} +EXPORT_SYMBOL_GPL(v4l2_h264_init_reflist_builder); + +static int v4l2_h264_p_ref_list_cmp(const void *ptra, const void *ptrb, + const void *data) +{ + const struct v4l2_h264_reflist_builder *builder = data; + u8 idxa, idxb; + + idxa = *((u8 *)ptra); + idxb = *((u8 *)ptrb); + + if (WARN_ON(idxa >= V4L2_H264_NUM_DPB_ENTRIES || + idxb >= V4L2_H264_NUM_DPB_ENTRIES)) + return 1; + + if (builder->refs[idxa].longterm != builder->refs[idxb].longterm) { + /* Short term pics first. */ + if (!builder->refs[idxa].longterm) + return -1; + else + return 1; + } + + /* + * Short term pics in descending pic num order, long term ones in + * ascending order. + */ + if (!builder->refs[idxa].longterm) + return builder->refs[idxb].frame_num < + builder->refs[idxa].frame_num ? + -1 : 1; + + return builder->refs[idxa].pic_num < builder->refs[idxb].pic_num ? + -1 : 1; +} + +static int v4l2_h264_b0_ref_list_cmp(const void *ptra, const void *ptrb, + const void *data) +{ + const struct v4l2_h264_reflist_builder *builder = data; + s32 poca, pocb; + u8 idxa, idxb; + + idxa = *((u8 *)ptra); + idxb = *((u8 *)ptrb); + + if (WARN_ON(idxa >= V4L2_H264_NUM_DPB_ENTRIES || + idxb >= V4L2_H264_NUM_DPB_ENTRIES)) + return 1; + + if (builder->refs[idxa].longterm != builder->refs[idxb].longterm) { + /* Short term pics first. */ + if (!builder->refs[idxa].longterm) + return -1; + else + return 1; + } + + /* Long term pics in ascending pic num order. */ + if (builder->refs[idxa].longterm) + return builder->refs[idxa].pic_num < + builder->refs[idxb].pic_num ? + -1 : 1; + + poca = builder->refs[idxa].pic_order_count; + pocb = builder->refs[idxb].pic_order_count; + + /* + * Short term pics with POC < cur POC first in POC descending order + * followed by short term pics with POC > cur POC in POC ascending + * order. + */ + if ((poca < builder->cur_pic_order_count) != + (pocb < builder->cur_pic_order_count)) + return poca < pocb ? -1 : 1; + else if (poca < builder->cur_pic_order_count) + return pocb < poca ? -1 : 1; + + return poca < pocb ? -1 : 1; +} + +static int v4l2_h264_b1_ref_list_cmp(const void *ptra, const void *ptrb, + const void *data) +{ + const struct v4l2_h264_reflist_builder *builder = data; + s32 poca, pocb; + u8 idxa, idxb; + + idxa = *((u8 *)ptra); + idxb = *((u8 *)ptrb); + + if (WARN_ON(idxa >= V4L2_H264_NUM_DPB_ENTRIES || + idxb >= V4L2_H264_NUM_DPB_ENTRIES)) + return 1; + + if (builder->refs[idxa].longterm != builder->refs[idxb].longterm) { + /* Short term pics first. */ + if (!builder->refs[idxa].longterm) + return -1; + else + return 1; + } + + /* Long term pics in ascending pic num order. */ + if (builder->refs[idxa].longterm) + return builder->refs[idxa].pic_num < + builder->refs[idxb].pic_num ? + -1 : 1; + + poca = builder->refs[idxa].pic_order_count; + pocb = builder->refs[idxb].pic_order_count; + + /* + * Short term pics with POC > cur POC first in POC ascending order + * followed by short term pics with POC < cur POC in POC descending + * order. + */ + if ((poca < builder->cur_pic_order_count) != + (pocb < builder->cur_pic_order_count)) + return pocb < poca ? -1 : 1; + else if (poca < builder->cur_pic_order_count) + return pocb < poca ? -1 : 1; + + return poca < pocb ? -1 : 1; +} + +/** + * v4l2_h264_build_p_ref_list() - Build the P reference list + * + * @builder: reference list builder context + * @reflist: 16-bytes array used to store the P reference list. Each entry + * is an index in the DPB + * + * This functions builds the P reference lists. This procedure is describe in + * section '8.2.4 Decoding process for reference picture lists construction' + * of the H264 spec. This function can be used by H264 decoder drivers that + * need to pass a P reference list to the hardware. + */ +void +v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder, + u8 *reflist) +{ + memcpy(reflist, builder->unordered_reflist, + sizeof(builder->unordered_reflist[0]) * builder->num_valid); + sort_r(reflist, builder->num_valid, sizeof(*reflist), + v4l2_h264_p_ref_list_cmp, NULL, builder); +} +EXPORT_SYMBOL_GPL(v4l2_h264_build_p_ref_list); + +/** + * v4l2_h264_build_b_ref_lists() - Build the B0/B1 reference lists + * + * @builder: reference list builder context + * @b0_reflist: 16-bytes array used to store the B0 reference list. Each entry + * is an index in the DPB + * @b1_reflist: 16-bytes array used to store the B1 reference list. Each entry + * is an index in the DPB + * + * This functions builds the B0/B1 reference lists. This procedure is described + * in section '8.2.4 Decoding process for reference picture lists construction' + * of the H264 spec. This function can be used by H264 decoder drivers that + * need to pass B0/B1 reference lists to the hardware. + */ +void +v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder, + u8 *b0_reflist, u8 *b1_reflist) +{ + memcpy(b0_reflist, builder->unordered_reflist, + sizeof(builder->unordered_reflist[0]) * builder->num_valid); + sort_r(b0_reflist, builder->num_valid, sizeof(*b0_reflist), + v4l2_h264_b0_ref_list_cmp, NULL, builder); + + memcpy(b1_reflist, builder->unordered_reflist, + sizeof(builder->unordered_reflist[0]) * builder->num_valid); + sort_r(b1_reflist, builder->num_valid, sizeof(*b1_reflist), + v4l2_h264_b1_ref_list_cmp, NULL, builder); + + if (builder->num_valid > 1 && + !memcmp(b1_reflist, b0_reflist, builder->num_valid)) + swap(b1_reflist[0], b1_reflist[1]); +} +EXPORT_SYMBOL_GPL(v4l2_h264_build_b_ref_lists); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("V4L2 H264 Helpers"); +MODULE_AUTHOR("Boris Brezillon "); -- cgit v1.2.3-59-g8ed1b