1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2019-2020 Pengutronix, Michael Tretter <kernel@pengutronix.de>
4  *
5  * Convert NAL units between raw byte sequence payloads (RBSP) and C structs.
6  *
7  * The conversion is defined in "ITU-T Rec. H.265 (02/2018) high efficiency
8  * video coding". Decoder drivers may use the parser to parse RBSP from
9  * encoded streams and configure the hardware, if the hardware is not able to
10  * parse RBSP itself. Encoder drivers may use the generator to generate the
11  * RBSP for VPS/SPS/PPS nal units and add them to the encoded stream if the
12  * hardware does not generate the units.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/types.h>
17 #include <linux/string.h>
18 #include <linux/v4l2-controls.h>
19 
20 #include <linux/device.h>
21 #include <linux/export.h>
22 #include <linux/log2.h>
23 
24 #include "nal-hevc.h"
25 #include "nal-rbsp.h"
26 
27 /*
28  * See Rec. ITU-T H.265 (02/2018) Table 7-1 – NAL unit type codes and NAL unit
29  * type classes
30  */
31 enum nal_unit_type {
32 	VPS_NUT = 32,
33 	SPS_NUT = 33,
34 	PPS_NUT = 34,
35 	FD_NUT = 38,
36 };
37 
38 int nal_hevc_profile_from_v4l2(enum v4l2_mpeg_video_hevc_profile profile)
39 {
40 	switch (profile) {
41 	case V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN:
42 		return 1;
43 	case V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN_10:
44 		return 2;
45 	case V4L2_MPEG_VIDEO_HEVC_PROFILE_MAIN_STILL_PICTURE:
46 		return 3;
47 	default:
48 		return -EINVAL;
49 	}
50 }
51 EXPORT_SYMBOL_GPL(nal_hevc_profile_from_v4l2);
52 
53 int nal_hevc_tier_from_v4l2(enum v4l2_mpeg_video_hevc_tier tier)
54 {
55 	switch (tier) {
56 	case V4L2_MPEG_VIDEO_HEVC_TIER_MAIN:
57 		return 0;
58 	case V4L2_MPEG_VIDEO_HEVC_TIER_HIGH:
59 		return 1;
60 	default:
61 		return -EINVAL;
62 	}
63 }
64 EXPORT_SYMBOL_GPL(nal_hevc_tier_from_v4l2);
65 
66 int nal_hevc_level_from_v4l2(enum v4l2_mpeg_video_hevc_level level)
67 {
68 	/*
69 	 * T-Rec-H.265 p. 280: general_level_idc and sub_layer_level_idc[ i ]
70 	 * shall be set equal to a value of 30 times the level number
71 	 * specified in Table A.6.
72 	 */
73 	int factor = 30 / 10;
74 
75 	switch (level) {
76 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_1:
77 		return factor * 10;
78 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_2:
79 		return factor * 20;
80 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_2_1:
81 		return factor * 21;
82 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_3:
83 		return factor * 30;
84 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_3_1:
85 		return factor * 31;
86 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_4:
87 		return factor * 40;
88 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_4_1:
89 		return factor * 41;
90 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_5:
91 		return factor * 50;
92 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_5_1:
93 		return factor * 51;
94 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_5_2:
95 		return factor * 52;
96 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_6:
97 		return factor * 60;
98 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_6_1:
99 		return factor * 61;
100 	case V4L2_MPEG_VIDEO_HEVC_LEVEL_6_2:
101 		return factor * 62;
102 	default:
103 		return -EINVAL;
104 	}
105 }
106 EXPORT_SYMBOL_GPL(nal_hevc_level_from_v4l2);
107 
108 static void nal_hevc_write_start_code_prefix(struct rbsp *rbsp)
109 {
110 	u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);
111 	int i = 4;
112 
113 	if (DIV_ROUND_UP(rbsp->pos, 8) + i > rbsp->size) {
114 		rbsp->error = -EINVAL;
115 		return;
116 	}
117 
118 	p[0] = 0x00;
119 	p[1] = 0x00;
120 	p[2] = 0x00;
121 	p[3] = 0x01;
122 
123 	rbsp->pos += i * 8;
124 }
125 
126 static void nal_hevc_read_start_code_prefix(struct rbsp *rbsp)
127 {
128 	u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);
129 	int i = 4;
130 
131 	if (DIV_ROUND_UP(rbsp->pos, 8) + i > rbsp->size) {
132 		rbsp->error = -EINVAL;
133 		return;
134 	}
135 
136 	if (p[0] != 0x00 || p[1] != 0x00 || p[2] != 0x00 || p[3] != 0x01) {
137 		rbsp->error = -EINVAL;
138 		return;
139 	}
140 
141 	rbsp->pos += i * 8;
142 }
143 
144 static void nal_hevc_write_filler_data(struct rbsp *rbsp)
145 {
146 	u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);
147 	int i;
148 
149 	/* Keep 1 byte extra for terminating the NAL unit */
150 	i = rbsp->size - DIV_ROUND_UP(rbsp->pos, 8) - 1;
151 	memset(p, 0xff, i);
152 	rbsp->pos += i * 8;
153 }
154 
155 static void nal_hevc_read_filler_data(struct rbsp *rbsp)
156 {
157 	u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);
158 
159 	while (*p == 0xff) {
160 		if (DIV_ROUND_UP(rbsp->pos, 8) > rbsp->size) {
161 			rbsp->error = -EINVAL;
162 			return;
163 		}
164 
165 		p++;
166 		rbsp->pos += 8;
167 	}
168 }
169 
170 static void nal_hevc_rbsp_profile_tier_level(struct rbsp *rbsp,
171 					     struct nal_hevc_profile_tier_level *ptl)
172 {
173 	unsigned int i;
174 	unsigned int max_num_sub_layers_minus_1 = 0;
175 
176 	rbsp_bits(rbsp, 2, &ptl->general_profile_space);
177 	rbsp_bit(rbsp, &ptl->general_tier_flag);
178 	rbsp_bits(rbsp, 5, &ptl->general_profile_idc);
179 	for (i = 0; i < 32; i++)
180 		rbsp_bit(rbsp, &ptl->general_profile_compatibility_flag[i]);
181 	rbsp_bit(rbsp, &ptl->general_progressive_source_flag);
182 	rbsp_bit(rbsp, &ptl->general_interlaced_source_flag);
183 	rbsp_bit(rbsp, &ptl->general_non_packed_constraint_flag);
184 	rbsp_bit(rbsp, &ptl->general_frame_only_constraint_flag);
185 	if (ptl->general_profile_idc == 4 ||
186 	    ptl->general_profile_compatibility_flag[4] ||
187 	    ptl->general_profile_idc == 5 ||
188 	    ptl->general_profile_compatibility_flag[5] ||
189 	    ptl->general_profile_idc == 6 ||
190 	    ptl->general_profile_compatibility_flag[6] ||
191 	    ptl->general_profile_idc == 7 ||
192 	    ptl->general_profile_compatibility_flag[7] ||
193 	    ptl->general_profile_idc == 8 ||
194 	    ptl->general_profile_compatibility_flag[8] ||
195 	    ptl->general_profile_idc == 9 ||
196 	    ptl->general_profile_compatibility_flag[9] ||
197 	    ptl->general_profile_idc == 10 ||
198 	    ptl->general_profile_compatibility_flag[10]) {
199 		rbsp_bit(rbsp, &ptl->general_max_12bit_constraint_flag);
200 		rbsp_bit(rbsp, &ptl->general_max_10bit_constraint_flag);
201 		rbsp_bit(rbsp, &ptl->general_max_8bit_constraint_flag);
202 		rbsp_bit(rbsp, &ptl->general_max_422chroma_constraint_flag);
203 		rbsp_bit(rbsp, &ptl->general_max_420chroma_constraint_flag);
204 		rbsp_bit(rbsp, &ptl->general_max_monochrome_constraint_flag);
205 		rbsp_bit(rbsp, &ptl->general_intra_constraint_flag);
206 		rbsp_bit(rbsp, &ptl->general_one_picture_only_constraint_flag);
207 		rbsp_bit(rbsp, &ptl->general_lower_bit_rate_constraint_flag);
208 		if (ptl->general_profile_idc == 5 ||
209 		    ptl->general_profile_compatibility_flag[5] ||
210 		    ptl->general_profile_idc == 9 ||
211 		    ptl->general_profile_compatibility_flag[9] ||
212 		    ptl->general_profile_idc == 10 ||
213 		    ptl->general_profile_compatibility_flag[10]) {
214 			rbsp_bit(rbsp, &ptl->general_max_14bit_constraint_flag);
215 			rbsp_bits(rbsp, 32, &ptl->general_reserved_zero_33bits);
216 			rbsp_bits(rbsp, 33 - 32, &ptl->general_reserved_zero_33bits);
217 		} else {
218 			rbsp_bits(rbsp, 32, &ptl->general_reserved_zero_34bits);
219 			rbsp_bits(rbsp, 34 - 2, &ptl->general_reserved_zero_34bits);
220 		}
221 	} else if (ptl->general_profile_idc == 2 ||
222 		   ptl->general_profile_compatibility_flag[2]) {
223 		rbsp_bits(rbsp, 7, &ptl->general_reserved_zero_7bits);
224 		rbsp_bit(rbsp, &ptl->general_one_picture_only_constraint_flag);
225 		rbsp_bits(rbsp, 32, &ptl->general_reserved_zero_35bits);
226 		rbsp_bits(rbsp, 35 - 32, &ptl->general_reserved_zero_35bits);
227 	} else {
228 		rbsp_bits(rbsp, 32, &ptl->general_reserved_zero_43bits);
229 		rbsp_bits(rbsp, 43 - 32, &ptl->general_reserved_zero_43bits);
230 	}
231 	if ((ptl->general_profile_idc >= 1 && ptl->general_profile_idc <= 5) ||
232 	    ptl->general_profile_idc == 9 ||
233 	    ptl->general_profile_compatibility_flag[1] ||
234 	    ptl->general_profile_compatibility_flag[2] ||
235 	    ptl->general_profile_compatibility_flag[3] ||
236 	    ptl->general_profile_compatibility_flag[4] ||
237 	    ptl->general_profile_compatibility_flag[5] ||
238 	    ptl->general_profile_compatibility_flag[9])
239 		rbsp_bit(rbsp, &ptl->general_inbld_flag);
240 	else
241 		rbsp_bit(rbsp, &ptl->general_reserved_zero_bit);
242 	rbsp_bits(rbsp, 8, &ptl->general_level_idc);
243 	if (max_num_sub_layers_minus_1 > 0)
244 		rbsp_unsupported(rbsp);
245 }
246 
247 static void nal_hevc_rbsp_vps(struct rbsp *rbsp, struct nal_hevc_vps *vps)
248 {
249 	unsigned int i, j;
250 	unsigned int reserved_0xffff_16bits = 0xffff;
251 
252 	rbsp_bits(rbsp, 4, &vps->video_parameter_set_id);
253 	rbsp_bit(rbsp, &vps->base_layer_internal_flag);
254 	rbsp_bit(rbsp, &vps->base_layer_available_flag);
255 	rbsp_bits(rbsp, 6, &vps->max_layers_minus1);
256 	rbsp_bits(rbsp, 3, &vps->max_sub_layers_minus1);
257 	rbsp_bits(rbsp, 1, &vps->temporal_id_nesting_flag);
258 	rbsp_bits(rbsp, 16, &reserved_0xffff_16bits);
259 	nal_hevc_rbsp_profile_tier_level(rbsp, &vps->profile_tier_level);
260 	rbsp_bit(rbsp, &vps->sub_layer_ordering_info_present_flag);
261 	for (i = vps->sub_layer_ordering_info_present_flag ? 0 : vps->max_sub_layers_minus1;
262 	     i <= vps->max_sub_layers_minus1; i++) {
263 		rbsp_uev(rbsp, &vps->max_dec_pic_buffering_minus1[i]);
264 		rbsp_uev(rbsp, &vps->max_num_reorder_pics[i]);
265 		rbsp_uev(rbsp, &vps->max_latency_increase_plus1[i]);
266 	}
267 	rbsp_bits(rbsp, 6, &vps->max_layer_id);
268 	rbsp_uev(rbsp, &vps->num_layer_sets_minus1);
269 	for (i = 0; i <= vps->num_layer_sets_minus1; i++)
270 		for (j = 0; j <= vps->max_layer_id; j++)
271 			rbsp_bit(rbsp, &vps->layer_id_included_flag[i][j]);
272 	rbsp_bit(rbsp, &vps->timing_info_present_flag);
273 	if (vps->timing_info_present_flag)
274 		rbsp_unsupported(rbsp);
275 	rbsp_bit(rbsp, &vps->extension_flag);
276 	if (vps->extension_flag)
277 		rbsp_unsupported(rbsp);
278 }
279 
280 static void nal_hevc_rbsp_sps(struct rbsp *rbsp, struct nal_hevc_sps *sps)
281 {
282 	unsigned int i;
283 
284 	rbsp_bits(rbsp, 4, &sps->video_parameter_set_id);
285 	rbsp_bits(rbsp, 3, &sps->max_sub_layers_minus1);
286 	rbsp_bit(rbsp, &sps->temporal_id_nesting_flag);
287 	nal_hevc_rbsp_profile_tier_level(rbsp, &sps->profile_tier_level);
288 	rbsp_uev(rbsp, &sps->seq_parameter_set_id);
289 
290 	rbsp_uev(rbsp, &sps->chroma_format_idc);
291 	if (sps->chroma_format_idc == 3)
292 		rbsp_bit(rbsp, &sps->separate_colour_plane_flag);
293 	rbsp_uev(rbsp, &sps->pic_width_in_luma_samples);
294 	rbsp_uev(rbsp, &sps->pic_height_in_luma_samples);
295 	rbsp_bit(rbsp, &sps->conformance_window_flag);
296 	if (sps->conformance_window_flag) {
297 		rbsp_uev(rbsp, &sps->conf_win_left_offset);
298 		rbsp_uev(rbsp, &sps->conf_win_right_offset);
299 		rbsp_uev(rbsp, &sps->conf_win_top_offset);
300 		rbsp_uev(rbsp, &sps->conf_win_bottom_offset);
301 	}
302 	rbsp_uev(rbsp, &sps->bit_depth_luma_minus8);
303 	rbsp_uev(rbsp, &sps->bit_depth_chroma_minus8);
304 
305 	rbsp_uev(rbsp, &sps->log2_max_pic_order_cnt_lsb_minus4);
306 
307 	rbsp_bit(rbsp, &sps->sub_layer_ordering_info_present_flag);
308 	for (i = (sps->sub_layer_ordering_info_present_flag ? 0 : sps->max_sub_layers_minus1);
309 	     i <= sps->max_sub_layers_minus1; i++) {
310 		rbsp_uev(rbsp, &sps->max_dec_pic_buffering_minus1[i]);
311 		rbsp_uev(rbsp, &sps->max_num_reorder_pics[i]);
312 		rbsp_uev(rbsp, &sps->max_latency_increase_plus1[i]);
313 	}
314 	rbsp_uev(rbsp, &sps->log2_min_luma_coding_block_size_minus3);
315 	rbsp_uev(rbsp, &sps->log2_diff_max_min_luma_coding_block_size);
316 	rbsp_uev(rbsp, &sps->log2_min_luma_transform_block_size_minus2);
317 	rbsp_uev(rbsp, &sps->log2_diff_max_min_luma_transform_block_size);
318 	rbsp_uev(rbsp, &sps->max_transform_hierarchy_depth_inter);
319 	rbsp_uev(rbsp, &sps->max_transform_hierarchy_depth_intra);
320 
321 	rbsp_bit(rbsp, &sps->scaling_list_enabled_flag);
322 	if (sps->scaling_list_enabled_flag)
323 		rbsp_unsupported(rbsp);
324 
325 	rbsp_bit(rbsp, &sps->amp_enabled_flag);
326 	rbsp_bit(rbsp, &sps->sample_adaptive_offset_enabled_flag);
327 	rbsp_bit(rbsp, &sps->pcm_enabled_flag);
328 	if (sps->pcm_enabled_flag) {
329 		rbsp_bits(rbsp, 4, &sps->pcm_sample_bit_depth_luma_minus1);
330 		rbsp_bits(rbsp, 4, &sps->pcm_sample_bit_depth_chroma_minus1);
331 		rbsp_uev(rbsp, &sps->log2_min_pcm_luma_coding_block_size_minus3);
332 		rbsp_uev(rbsp, &sps->log2_diff_max_min_pcm_luma_coding_block_size);
333 		rbsp_bit(rbsp, &sps->pcm_loop_filter_disabled_flag);
334 	}
335 
336 	rbsp_uev(rbsp, &sps->num_short_term_ref_pic_sets);
337 	if (sps->num_short_term_ref_pic_sets > 0)
338 		rbsp_unsupported(rbsp);
339 
340 	rbsp_bit(rbsp, &sps->long_term_ref_pics_present_flag);
341 	if (sps->long_term_ref_pics_present_flag)
342 		rbsp_unsupported(rbsp);
343 
344 	rbsp_bit(rbsp, &sps->sps_temporal_mvp_enabled_flag);
345 	rbsp_bit(rbsp, &sps->strong_intra_smoothing_enabled_flag);
346 	rbsp_bit(rbsp, &sps->vui_parameters_present_flag);
347 	if (sps->vui_parameters_present_flag)
348 		rbsp_unsupported(rbsp);
349 
350 	rbsp_bit(rbsp, &sps->extension_present_flag);
351 	if (sps->extension_present_flag) {
352 		rbsp_bit(rbsp, &sps->sps_range_extension_flag);
353 		rbsp_bit(rbsp, &sps->sps_multilayer_extension_flag);
354 		rbsp_bit(rbsp, &sps->sps_3d_extension_flag);
355 		rbsp_bit(rbsp, &sps->sps_scc_extension_flag);
356 		rbsp_bits(rbsp, 5, &sps->sps_extension_4bits);
357 	}
358 	if (sps->sps_range_extension_flag)
359 		rbsp_unsupported(rbsp);
360 	if (sps->sps_multilayer_extension_flag)
361 		rbsp_unsupported(rbsp);
362 	if (sps->sps_3d_extension_flag)
363 		rbsp_unsupported(rbsp);
364 	if (sps->sps_scc_extension_flag)
365 		rbsp_unsupported(rbsp);
366 	if (sps->sps_extension_4bits)
367 		rbsp_unsupported(rbsp);
368 }
369 
370 static void nal_hevc_rbsp_pps(struct rbsp *rbsp, struct nal_hevc_pps *pps)
371 {
372 	unsigned int i;
373 
374 	rbsp_uev(rbsp, &pps->pps_pic_parameter_set_id);
375 	rbsp_uev(rbsp, &pps->pps_seq_parameter_set_id);
376 	rbsp_bit(rbsp, &pps->dependent_slice_segments_enabled_flag);
377 	rbsp_bit(rbsp, &pps->output_flag_present_flag);
378 	rbsp_bits(rbsp, 3, &pps->num_extra_slice_header_bits);
379 	rbsp_bit(rbsp, &pps->sign_data_hiding_enabled_flag);
380 	rbsp_bit(rbsp, &pps->cabac_init_present_flag);
381 	rbsp_uev(rbsp, &pps->num_ref_idx_l0_default_active_minus1);
382 	rbsp_uev(rbsp, &pps->num_ref_idx_l1_default_active_minus1);
383 	rbsp_sev(rbsp, &pps->init_qp_minus26);
384 	rbsp_bit(rbsp, &pps->constrained_intra_pred_flag);
385 	rbsp_bit(rbsp, &pps->transform_skip_enabled_flag);
386 	rbsp_bit(rbsp, &pps->cu_qp_delta_enabled_flag);
387 	if (pps->cu_qp_delta_enabled_flag)
388 		rbsp_uev(rbsp, &pps->diff_cu_qp_delta_depth);
389 	rbsp_sev(rbsp, &pps->pps_cb_qp_offset);
390 	rbsp_sev(rbsp, &pps->pps_cr_qp_offset);
391 	rbsp_bit(rbsp, &pps->pps_slice_chroma_qp_offsets_present_flag);
392 	rbsp_bit(rbsp, &pps->weighted_pred_flag);
393 	rbsp_bit(rbsp, &pps->weighted_bipred_flag);
394 	rbsp_bit(rbsp, &pps->transquant_bypass_enabled_flag);
395 	rbsp_bit(rbsp, &pps->tiles_enabled_flag);
396 	rbsp_bit(rbsp, &pps->entropy_coding_sync_enabled_flag);
397 	if (pps->tiles_enabled_flag) {
398 		rbsp_uev(rbsp, &pps->num_tile_columns_minus1);
399 		rbsp_uev(rbsp, &pps->num_tile_rows_minus1);
400 		rbsp_bit(rbsp, &pps->uniform_spacing_flag);
401 		if (!pps->uniform_spacing_flag) {
402 			for (i = 0; i < pps->num_tile_columns_minus1; i++)
403 				rbsp_uev(rbsp, &pps->column_width_minus1[i]);
404 			for (i = 0; i < pps->num_tile_rows_minus1; i++)
405 				rbsp_uev(rbsp, &pps->row_height_minus1[i]);
406 		}
407 		rbsp_bit(rbsp, &pps->loop_filter_across_tiles_enabled_flag);
408 	}
409 	rbsp_bit(rbsp, &pps->pps_loop_filter_across_slices_enabled_flag);
410 	rbsp_bit(rbsp, &pps->deblocking_filter_control_present_flag);
411 	if (pps->deblocking_filter_control_present_flag) {
412 		rbsp_bit(rbsp, &pps->deblocking_filter_override_enabled_flag);
413 		rbsp_bit(rbsp, &pps->pps_deblocking_filter_disabled_flag);
414 		if (!pps->pps_deblocking_filter_disabled_flag) {
415 			rbsp_sev(rbsp, &pps->pps_beta_offset_div2);
416 			rbsp_sev(rbsp, &pps->pps_tc_offset_div2);
417 		}
418 	}
419 	rbsp_bit(rbsp, &pps->pps_scaling_list_data_present_flag);
420 	if (pps->pps_scaling_list_data_present_flag)
421 		rbsp_unsupported(rbsp);
422 	rbsp_bit(rbsp, &pps->lists_modification_present_flag);
423 	rbsp_uev(rbsp, &pps->log2_parallel_merge_level_minus2);
424 	rbsp_bit(rbsp, &pps->slice_segment_header_extension_present_flag);
425 	rbsp_bit(rbsp, &pps->pps_extension_present_flag);
426 	if (pps->pps_extension_present_flag) {
427 		rbsp_bit(rbsp, &pps->pps_range_extension_flag);
428 		rbsp_bit(rbsp, &pps->pps_multilayer_extension_flag);
429 		rbsp_bit(rbsp, &pps->pps_3d_extension_flag);
430 		rbsp_bit(rbsp, &pps->pps_scc_extension_flag);
431 		rbsp_bits(rbsp, 4, &pps->pps_extension_4bits);
432 	}
433 	if (pps->pps_range_extension_flag)
434 		rbsp_unsupported(rbsp);
435 	if (pps->pps_multilayer_extension_flag)
436 		rbsp_unsupported(rbsp);
437 	if (pps->pps_3d_extension_flag)
438 		rbsp_unsupported(rbsp);
439 	if (pps->pps_scc_extension_flag)
440 		rbsp_unsupported(rbsp);
441 	if (pps->pps_extension_4bits)
442 		rbsp_unsupported(rbsp);
443 }
444 
445 /**
446  * nal_hevc_write_vps() - Write PPS NAL unit into RBSP format
447  * @dev: device pointer
448  * @dest: the buffer that is filled with RBSP data
449  * @n: maximum size of @dest in bytes
450  * @vps: &struct nal_hevc_vps to convert to RBSP
451  *
452  * Convert @vps to RBSP data and write it into @dest.
453  *
454  * The size of the VPS NAL unit is not known in advance and this function will
455  * fail, if @dest does not hold sufficient space for the VPS NAL unit.
456  *
457  * Return: number of bytes written to @dest or negative error code
458  */
459 ssize_t nal_hevc_write_vps(const struct device *dev,
460 			   void *dest, size_t n, struct nal_hevc_vps *vps)
461 {
462 	struct rbsp rbsp;
463 	unsigned int forbidden_zero_bit = 0;
464 	unsigned int nal_unit_type = VPS_NUT;
465 	unsigned int nuh_layer_id = 0;
466 	unsigned int nuh_temporal_id_plus1 = 1;
467 
468 	if (!dest)
469 		return -EINVAL;
470 
471 	rbsp_init(&rbsp, dest, n, &write);
472 
473 	nal_hevc_write_start_code_prefix(&rbsp);
474 
475 	/* NAL unit header */
476 	rbsp_bit(&rbsp, &forbidden_zero_bit);
477 	rbsp_bits(&rbsp, 6, &nal_unit_type);
478 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
479 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
480 
481 	nal_hevc_rbsp_vps(&rbsp, vps);
482 
483 	rbsp_trailing_bits(&rbsp);
484 
485 	if (rbsp.error)
486 		return rbsp.error;
487 
488 	return DIV_ROUND_UP(rbsp.pos, 8);
489 }
490 EXPORT_SYMBOL_GPL(nal_hevc_write_vps);
491 
492 /**
493  * nal_hevc_read_vps() - Read VPS NAL unit from RBSP format
494  * @dev: device pointer
495  * @vps: the &struct nal_hevc_vps to fill from the RBSP data
496  * @src: the buffer that contains the RBSP data
497  * @n: size of @src in bytes
498  *
499  * Read RBSP data from @src and use it to fill @vps.
500  *
501  * Return: number of bytes read from @src or negative error code
502  */
503 ssize_t nal_hevc_read_vps(const struct device *dev,
504 			  struct nal_hevc_vps *vps, void *src, size_t n)
505 {
506 	struct rbsp rbsp;
507 	unsigned int forbidden_zero_bit;
508 	unsigned int nal_unit_type;
509 	unsigned int nuh_layer_id;
510 	unsigned int nuh_temporal_id_plus1;
511 
512 	if (!src)
513 		return -EINVAL;
514 
515 	rbsp_init(&rbsp, src, n, &read);
516 
517 	nal_hevc_read_start_code_prefix(&rbsp);
518 
519 	rbsp_bit(&rbsp, &forbidden_zero_bit);
520 	rbsp_bits(&rbsp, 6, &nal_unit_type);
521 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
522 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
523 
524 	if (rbsp.error ||
525 	    forbidden_zero_bit != 0 ||
526 	    nal_unit_type != VPS_NUT)
527 		return -EINVAL;
528 
529 	nal_hevc_rbsp_vps(&rbsp, vps);
530 
531 	rbsp_trailing_bits(&rbsp);
532 
533 	if (rbsp.error)
534 		return rbsp.error;
535 
536 	return DIV_ROUND_UP(rbsp.pos, 8);
537 }
538 EXPORT_SYMBOL_GPL(nal_hevc_read_vps);
539 
540 /**
541  * nal_hevc_write_sps() - Write SPS NAL unit into RBSP format
542  * @dev: device pointer
543  * @dest: the buffer that is filled with RBSP data
544  * @n: maximum size of @dest in bytes
545  * @sps: &struct nal_hevc_sps to convert to RBSP
546  *
547  * Convert @sps to RBSP data and write it into @dest.
548  *
549  * The size of the SPS NAL unit is not known in advance and this function will
550  * fail, if @dest does not hold sufficient space for the SPS NAL unit.
551  *
552  * Return: number of bytes written to @dest or negative error code
553  */
554 ssize_t nal_hevc_write_sps(const struct device *dev,
555 			   void *dest, size_t n, struct nal_hevc_sps *sps)
556 {
557 	struct rbsp rbsp;
558 	unsigned int forbidden_zero_bit = 0;
559 	unsigned int nal_unit_type = SPS_NUT;
560 	unsigned int nuh_layer_id = 0;
561 	unsigned int nuh_temporal_id_plus1 = 1;
562 
563 	if (!dest)
564 		return -EINVAL;
565 
566 	rbsp_init(&rbsp, dest, n, &write);
567 
568 	nal_hevc_write_start_code_prefix(&rbsp);
569 
570 	/* NAL unit header */
571 	rbsp_bit(&rbsp, &forbidden_zero_bit);
572 	rbsp_bits(&rbsp, 6, &nal_unit_type);
573 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
574 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
575 
576 	nal_hevc_rbsp_sps(&rbsp, sps);
577 
578 	rbsp_trailing_bits(&rbsp);
579 
580 	if (rbsp.error)
581 		return rbsp.error;
582 
583 	return DIV_ROUND_UP(rbsp.pos, 8);
584 }
585 EXPORT_SYMBOL_GPL(nal_hevc_write_sps);
586 
587 /**
588  * nal_hevc_read_sps() - Read SPS NAL unit from RBSP format
589  * @dev: device pointer
590  * @sps: the &struct nal_hevc_sps to fill from the RBSP data
591  * @src: the buffer that contains the RBSP data
592  * @n: size of @src in bytes
593  *
594  * Read RBSP data from @src and use it to fill @sps.
595  *
596  * Return: number of bytes read from @src or negative error code
597  */
598 ssize_t nal_hevc_read_sps(const struct device *dev,
599 			  struct nal_hevc_sps *sps, void *src, size_t n)
600 {
601 	struct rbsp rbsp;
602 	unsigned int forbidden_zero_bit;
603 	unsigned int nal_unit_type;
604 	unsigned int nuh_layer_id;
605 	unsigned int nuh_temporal_id_plus1;
606 
607 	if (!src)
608 		return -EINVAL;
609 
610 	rbsp_init(&rbsp, src, n, &read);
611 
612 	nal_hevc_read_start_code_prefix(&rbsp);
613 
614 	rbsp_bit(&rbsp, &forbidden_zero_bit);
615 	rbsp_bits(&rbsp, 6, &nal_unit_type);
616 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
617 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
618 
619 	if (rbsp.error ||
620 	    forbidden_zero_bit != 0 ||
621 	    nal_unit_type != SPS_NUT)
622 		return -EINVAL;
623 
624 	nal_hevc_rbsp_sps(&rbsp, sps);
625 
626 	rbsp_trailing_bits(&rbsp);
627 
628 	if (rbsp.error)
629 		return rbsp.error;
630 
631 	return DIV_ROUND_UP(rbsp.pos, 8);
632 }
633 EXPORT_SYMBOL_GPL(nal_hevc_read_sps);
634 
635 /**
636  * nal_hevc_write_pps() - Write PPS NAL unit into RBSP format
637  * @dev: device pointer
638  * @dest: the buffer that is filled with RBSP data
639  * @n: maximum size of @dest in bytes
640  * @pps: &struct nal_hevc_pps to convert to RBSP
641  *
642  * Convert @pps to RBSP data and write it into @dest.
643  *
644  * The size of the PPS NAL unit is not known in advance and this function will
645  * fail, if @dest does not hold sufficient space for the PPS NAL unit.
646  *
647  * Return: number of bytes written to @dest or negative error code
648  */
649 ssize_t nal_hevc_write_pps(const struct device *dev,
650 			   void *dest, size_t n, struct nal_hevc_pps *pps)
651 {
652 	struct rbsp rbsp;
653 	unsigned int forbidden_zero_bit = 0;
654 	unsigned int nal_unit_type = PPS_NUT;
655 	unsigned int nuh_layer_id = 0;
656 	unsigned int nuh_temporal_id_plus1 = 1;
657 
658 	if (!dest)
659 		return -EINVAL;
660 
661 	rbsp_init(&rbsp, dest, n, &write);
662 
663 	nal_hevc_write_start_code_prefix(&rbsp);
664 
665 	/* NAL unit header */
666 	rbsp_bit(&rbsp, &forbidden_zero_bit);
667 	rbsp_bits(&rbsp, 6, &nal_unit_type);
668 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
669 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
670 
671 	nal_hevc_rbsp_pps(&rbsp, pps);
672 
673 	rbsp_trailing_bits(&rbsp);
674 
675 	if (rbsp.error)
676 		return rbsp.error;
677 
678 	return DIV_ROUND_UP(rbsp.pos, 8);
679 }
680 EXPORT_SYMBOL_GPL(nal_hevc_write_pps);
681 
682 /**
683  * nal_hevc_read_pps() - Read PPS NAL unit from RBSP format
684  * @dev: device pointer
685  * @pps: the &struct nal_hevc_pps to fill from the RBSP data
686  * @src: the buffer that contains the RBSP data
687  * @n: size of @src in bytes
688  *
689  * Read RBSP data from @src and use it to fill @pps.
690  *
691  * Return: number of bytes read from @src or negative error code
692  */
693 ssize_t nal_hevc_read_pps(const struct device *dev,
694 			  struct nal_hevc_pps *pps, void *src, size_t n)
695 {
696 	struct rbsp rbsp;
697 	unsigned int forbidden_zero_bit;
698 	unsigned int nal_unit_type;
699 	unsigned int nuh_layer_id;
700 	unsigned int nuh_temporal_id_plus1;
701 
702 	if (!src)
703 		return -EINVAL;
704 
705 	rbsp_init(&rbsp, src, n, &read);
706 
707 	nal_hevc_read_start_code_prefix(&rbsp);
708 
709 	/* NAL unit header */
710 	rbsp_bit(&rbsp, &forbidden_zero_bit);
711 	rbsp_bits(&rbsp, 6, &nal_unit_type);
712 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
713 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
714 
715 	nal_hevc_rbsp_pps(&rbsp, pps);
716 
717 	rbsp_trailing_bits(&rbsp);
718 
719 	if (rbsp.error)
720 		return rbsp.error;
721 
722 	return DIV_ROUND_UP(rbsp.pos, 8);
723 }
724 EXPORT_SYMBOL_GPL(nal_hevc_read_pps);
725 
726 /**
727  * nal_hevc_write_filler() - Write filler data RBSP
728  * @dev: device pointer
729  * @dest: buffer to fill with filler data
730  * @n: size of the buffer to fill with filler data
731  *
732  * Write a filler data RBSP to @dest with a size of @n bytes and return the
733  * number of written filler data bytes.
734  *
735  * Use this function to generate dummy data in an RBSP data stream that can be
736  * safely ignored by hevc decoders.
737  *
738  * The RBSP format of the filler data is specified in Rec. ITU-T H.265
739  * (02/2018) 7.3.2.8 Filler data RBSP syntax.
740  *
741  * Return: number of filler data bytes (including marker) or negative error
742  */
743 ssize_t nal_hevc_write_filler(const struct device *dev, void *dest, size_t n)
744 {
745 	struct rbsp rbsp;
746 	unsigned int forbidden_zero_bit = 0;
747 	unsigned int nal_unit_type = FD_NUT;
748 	unsigned int nuh_layer_id = 0;
749 	unsigned int nuh_temporal_id_plus1 = 1;
750 
751 	if (!dest)
752 		return -EINVAL;
753 
754 	rbsp_init(&rbsp, dest, n, &write);
755 
756 	nal_hevc_write_start_code_prefix(&rbsp);
757 
758 	rbsp_bit(&rbsp, &forbidden_zero_bit);
759 	rbsp_bits(&rbsp, 6, &nal_unit_type);
760 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
761 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
762 
763 	nal_hevc_write_filler_data(&rbsp);
764 	rbsp_trailing_bits(&rbsp);
765 
766 	if (rbsp.error)
767 		return rbsp.error;
768 
769 	return DIV_ROUND_UP(rbsp.pos, 8);
770 }
771 EXPORT_SYMBOL_GPL(nal_hevc_write_filler);
772 
773 /**
774  * nal_hevc_read_filler() - Read filler data RBSP
775  * @dev: device pointer
776  * @src: buffer with RBSP data that is read
777  * @n: maximum size of src that shall be read
778  *
779  * Read a filler data RBSP from @src up to a maximum size of @n bytes and
780  * return the size of the filler data in bytes including the marker.
781  *
782  * This function is used to parse filler data and skip the respective bytes in
783  * the RBSP data.
784  *
785  * The RBSP format of the filler data is specified in Rec. ITU-T H.265
786  * (02/2018) 7.3.2.8 Filler data RBSP syntax.
787  *
788  * Return: number of filler data bytes (including marker) or negative error
789  */
790 ssize_t nal_hevc_read_filler(const struct device *dev, void *src, size_t n)
791 {
792 	struct rbsp rbsp;
793 	unsigned int forbidden_zero_bit;
794 	unsigned int nal_unit_type;
795 	unsigned int nuh_layer_id;
796 	unsigned int nuh_temporal_id_plus1;
797 
798 	if (!src)
799 		return -EINVAL;
800 
801 	rbsp_init(&rbsp, src, n, &read);
802 
803 	nal_hevc_read_start_code_prefix(&rbsp);
804 
805 	rbsp_bit(&rbsp, &forbidden_zero_bit);
806 	rbsp_bits(&rbsp, 6, &nal_unit_type);
807 	rbsp_bits(&rbsp, 6, &nuh_layer_id);
808 	rbsp_bits(&rbsp, 3, &nuh_temporal_id_plus1);
809 
810 	if (rbsp.error)
811 		return rbsp.error;
812 	if (forbidden_zero_bit != 0 ||
813 	    nal_unit_type != FD_NUT)
814 		return -EINVAL;
815 
816 	nal_hevc_read_filler_data(&rbsp);
817 	rbsp_trailing_bits(&rbsp);
818 
819 	if (rbsp.error)
820 		return rbsp.error;
821 
822 	return DIV_ROUND_UP(rbsp.pos, 8);
823 }
824 EXPORT_SYMBOL_GPL(nal_hevc_read_filler);
825