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1// SPDX-License-Identifier: GPL-2.02/*3 * Vidtv serves as a reference DVB driver and helps validate the existing APIs4 * in the media subsystem. It can also aid developers working on userspace5 * applications.6 *7 * This file contains the code for an AES3 (also known as AES/EBU) encoder.8 * It is based on EBU Tech 3250 and SMPTE 302M technical documents.9 *10 * This encoder currently supports 16bit AES3 subframes using 16bit signed11 * integers.12 *13 * Note: AU stands for Access Unit, and AAU stands for Audio Access Unit14 *15 * Copyright (C) 2020 Daniel W. S. Almeida16 */17 18#define pr_fmt(fmt) KBUILD_MODNAME ":%s, %d: " fmt, __func__, __LINE__19 20#include <linux/bug.h>21#include <linux/crc32.h>22#include <linux/fixp-arith.h>23#include <linux/jiffies.h>24#include <linux/kernel.h>25#include <linux/math64.h>26#include <linux/printk.h>27#include <linux/ratelimit.h>28#include <linux/slab.h>29#include <linux/string.h>30#include <linux/types.h>31#include <linux/vmalloc.h>32 33#include "vidtv_common.h"34#include "vidtv_encoder.h"35#include "vidtv_s302m.h"36 37#define S302M_SAMPLING_RATE_HZ 4800038#define PES_PRIVATE_STREAM_1 0xbd /* PES: private_stream_1 */39#define S302M_BLOCK_SZ 19240#define S302M_SIN_LUT_NUM_ELEM 102441 42/* these are retrieved empirically from ffmpeg/libavcodec */43#define FF_S302M_DEFAULT_NUM_FRAMES 111544#define FF_S302M_DEFAULT_PTS_INCREMENT 209045#define FF_S302M_DEFAULT_PTS_OFFSET 10000046 47/* Used by the tone generator: number of samples for PI */48#define PI 18049 50static const u8 reverse[256] = {51 /* from ffmpeg */52 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0,53 0x30, 0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,54 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4,55 0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,56 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC,57 0x3C, 0xBC, 0x7C, 0xFC, 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,58 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, 0x0A, 0x8A, 0x4A, 0xCA,59 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,60 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6,61 0x36, 0xB6, 0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,62 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81, 0x41, 0xC1,63 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,64 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9,65 0x39, 0xB9, 0x79, 0xF9, 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,66 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD,67 0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,68 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3,69 0x33, 0xB3, 0x73, 0xF3, 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,70 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7,71 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,72 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF,73 0x3F, 0xBF, 0x7F, 0xFF,74};75 76struct tone_duration {77 enum musical_notes note;78 int duration;79};80 81#define COMPASS 100 /* beats per minute */82static const struct tone_duration beethoven_fur_elise[] = {83 { NOTE_SILENT, 512},84 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},85 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},86 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},87 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},88 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},89 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},90 { NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},91 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},92 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},93 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},94 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},95 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},96 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},97 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},98 { NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},99 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_SILENT, 128},100 101 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},102 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},103 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},104 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},105 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},106 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},107 { NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},108 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},109 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},110 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},111 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},112 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},113 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},114 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},115 { NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},116 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_B_4, 128},117 { NOTE_C_5, 128}, { NOTE_D_5, 128}, { NOTE_C_4, 128},118 { NOTE_G_4, 128}, { NOTE_C_5, 128}, { NOTE_G_4, 128},119 { NOTE_F_5, 128}, { NOTE_E_5, 128}, { NOTE_G_3, 128},120 { NOTE_G_4, 128}, { NOTE_B_3, 128}, { NOTE_F_4, 128},121 { NOTE_E_5, 128}, { NOTE_D_5, 128}, { NOTE_A_3, 128},122 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_4, 128},123 { NOTE_D_5, 128}, { NOTE_C_5, 128}, { NOTE_E_3, 128},124 { NOTE_E_4, 128}, { NOTE_E_5, 128}, { NOTE_E_5, 128},125 { NOTE_E_6, 128}, { NOTE_E_5, 128}, { NOTE_E_6, 128},126 { NOTE_E_5, 128}, { NOTE_E_5, 128}, { NOTE_DS_5, 128},127 { NOTE_E_5, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},128 { NOTE_DS_5, 128}, { NOTE_E_5, 128}, { NOTE_DS_6, 128},129 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},130 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},131 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},132 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},133 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},134 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},135 { NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},136 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},137 { NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},138 { NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},139 { NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},140 { NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},141 { NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},142 { NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},143 { NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_5, 512},144 { NOTE_SILENT, 256},145};146 147static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)148{149 struct vidtv_access_unit *au;150 151 au = kzalloc(sizeof(*au), GFP_KERNEL);152 if (!au)153 return NULL;154 155 if (head) {156 while (head->next)157 head = head->next;158 159 head->next = au;160 }161 162 return au;163}164 165static void vidtv_s302m_access_unit_destroy(struct vidtv_encoder *e)166{167 struct vidtv_access_unit *head = e->access_units;168 struct vidtv_access_unit *tmp = NULL;169 170 while (head) {171 tmp = head;172 head = head->next;173 kfree(tmp);174 }175 176 e->access_units = NULL;177}178 179static void vidtv_s302m_alloc_au(struct vidtv_encoder *e)180{181 struct vidtv_access_unit *sync_au = NULL;182 struct vidtv_access_unit *temp = NULL;183 184 if (e->sync && e->sync->is_video_encoder) {185 sync_au = e->sync->access_units;186 187 while (sync_au) {188 temp = vidtv_s302m_access_unit_init(e->access_units);189 if (!e->access_units)190 e->access_units = temp;191 192 sync_au = sync_au->next;193 }194 195 return;196 }197 198 e->access_units = vidtv_s302m_access_unit_init(NULL);199}200 201static void202vidtv_s302m_compute_sample_count_from_video(struct vidtv_encoder *e)203{204 struct vidtv_access_unit *sync_au = e->sync->access_units;205 struct vidtv_access_unit *au = e->access_units;206 u32 sample_duration_usecs;207 u32 vau_duration_usecs;208 u32 s;209 210 vau_duration_usecs = USEC_PER_SEC / e->sync->sampling_rate_hz;211 sample_duration_usecs = USEC_PER_SEC / e->sampling_rate_hz;212 213 while (au && sync_au) {214 s = DIV_ROUND_UP(vau_duration_usecs, sample_duration_usecs);215 au->num_samples = s;216 au = au->next;217 sync_au = sync_au->next;218 }219}220 221static void vidtv_s302m_compute_pts_from_video(struct vidtv_encoder *e)222{223 struct vidtv_access_unit *au = e->access_units;224 struct vidtv_access_unit *sync_au = e->sync->access_units;225 226 /* use the same pts from the video access unit*/227 while (au && sync_au) {228 au->pts = sync_au->pts;229 au = au->next;230 sync_au = sync_au->next;231 }232}233 234static u16 vidtv_s302m_get_sample(struct vidtv_encoder *e)235{236 u16 sample;237 int pos;238 struct vidtv_s302m_ctx *ctx = e->ctx;239 240 if (!e->src_buf) {241 /*242 * Simple tone generator: play the tones at the243 * beethoven_fur_elise array.244 */245 if (ctx->last_duration <= 0) {246 if (e->src_buf_offset >= ARRAY_SIZE(beethoven_fur_elise))247 e->src_buf_offset = 0;248 249 ctx->last_tone = beethoven_fur_elise[e->src_buf_offset].note;250 ctx->last_duration = beethoven_fur_elise[e->src_buf_offset].duration *251 S302M_SAMPLING_RATE_HZ / COMPASS / 5;252 e->src_buf_offset++;253 ctx->note_offset = 0;254 } else {255 ctx->last_duration--;256 }257 258 /* Handle pause notes */259 if (!ctx->last_tone)260 return 0x8000;261 262 pos = (2 * PI * ctx->note_offset * ctx->last_tone) / S302M_SAMPLING_RATE_HZ;263 ctx->note_offset++;264 265 return (fixp_sin32(pos % (2 * PI)) >> 16) + 0x8000;266 }267 268 /* bug somewhere */269 if (e->src_buf_offset > e->src_buf_sz) {270 pr_err_ratelimited("overflow detected: %d > %d, wrapping.\n",271 e->src_buf_offset,272 e->src_buf_sz);273 274 e->src_buf_offset = 0;275 }276 277 if (e->src_buf_offset >= e->src_buf_sz) {278 /* let the source know we are out of data */279 if (e->last_sample_cb)280 e->last_sample_cb(e->sample_count);281 282 e->src_buf_offset = 0;283 }284 285 sample = *(u16 *)(e->src_buf + e->src_buf_offset);286 287 return sample;288}289 290static u32 vidtv_s302m_write_frame(struct vidtv_encoder *e,291 u16 sample)292{293 struct vidtv_s302m_ctx *ctx = e->ctx;294 struct vidtv_s302m_frame_16 f = {};295 u32 nbytes = 0;296 297 /* from ffmpeg: see s302enc.c */298 299 u8 vucf = ctx->frame_index == 0 ? 0x10 : 0;300 301 f.data[0] = sample & 0xFF;302 f.data[1] = (sample & 0xFF00) >> 8;303 f.data[2] = ((sample & 0x0F) << 4) | vucf;304 f.data[3] = (sample & 0x0FF0) >> 4;305 f.data[4] = (sample & 0xF000) >> 12;306 307 f.data[0] = reverse[f.data[0]];308 f.data[1] = reverse[f.data[1]];309 f.data[2] = reverse[f.data[2]];310 f.data[3] = reverse[f.data[3]];311 f.data[4] = reverse[f.data[4]];312 313 nbytes += vidtv_memcpy(e->encoder_buf,314 e->encoder_buf_offset,315 VIDTV_S302M_BUF_SZ,316 &f,317 sizeof(f));318 319 e->encoder_buf_offset += nbytes;320 321 ctx->frame_index++;322 if (ctx->frame_index >= S302M_BLOCK_SZ)323 ctx->frame_index = 0;324 325 return nbytes;326}327 328static u32 vidtv_s302m_write_h(struct vidtv_encoder *e, u32 p_sz)329{330 struct vidtv_smpte_s302m_es h = {};331 u32 nbytes = 0;332 333 /* 2 channels, ident: 0, 16 bits per sample */334 h.bitfield = cpu_to_be32((p_sz << 16));335 336 nbytes += vidtv_memcpy(e->encoder_buf,337 e->encoder_buf_offset,338 e->encoder_buf_sz,339 &h,340 sizeof(h));341 342 e->encoder_buf_offset += nbytes;343 return nbytes;344}345 346static void vidtv_s302m_write_frames(struct vidtv_encoder *e)347{348 struct vidtv_access_unit *au = e->access_units;349 struct vidtv_s302m_ctx *ctx = e->ctx;350 u32 nbytes_per_unit = 0;351 u32 nbytes = 0;352 u32 au_sz = 0;353 u16 sample;354 u32 j;355 356 while (au) {357 au_sz = au->num_samples *358 sizeof(struct vidtv_s302m_frame_16);359 360 nbytes_per_unit = vidtv_s302m_write_h(e, au_sz);361 362 for (j = 0; j < au->num_samples; ++j) {363 sample = vidtv_s302m_get_sample(e);364 nbytes_per_unit += vidtv_s302m_write_frame(e, sample);365 366 if (e->src_buf)367 e->src_buf_offset += sizeof(u16);368 369 e->sample_count++;370 }371 372 au->nbytes = nbytes_per_unit;373 374 if (au_sz + sizeof(struct vidtv_smpte_s302m_es) != nbytes_per_unit) {375 pr_warn_ratelimited("write size was %u, expected %zu\n",376 nbytes_per_unit,377 au_sz + sizeof(struct vidtv_smpte_s302m_es));378 }379 380 nbytes += nbytes_per_unit;381 au->offset = nbytes - nbytes_per_unit;382 383 nbytes_per_unit = 0;384 ctx->au_count++;385 386 au = au->next;387 }388}389 390static void *vidtv_s302m_encode(struct vidtv_encoder *e)391{392 struct vidtv_s302m_ctx *ctx = e->ctx;393 394 /*395 * According to SMPTE 302M, an audio access unit is specified as those396 * AES3 words that are associated with a corresponding video frame.397 * Therefore, there is one audio access unit for every video access unit398 * in the corresponding video encoder ('sync'), using the same values399 * for PTS as used by the video encoder.400 *401 * Assuming that it is also possible to send audio without any402 * associated video, as in a radio-like service, a single audio access unit403 * is created with values for 'num_samples' and 'pts' taken empirically from404 * ffmpeg405 */406 407 vidtv_s302m_access_unit_destroy(e);408 vidtv_s302m_alloc_au(e);409 410 if (e->sync && e->sync->is_video_encoder) {411 vidtv_s302m_compute_sample_count_from_video(e);412 vidtv_s302m_compute_pts_from_video(e);413 } else {414 e->access_units->num_samples = FF_S302M_DEFAULT_NUM_FRAMES;415 e->access_units->pts = (ctx->au_count * FF_S302M_DEFAULT_PTS_INCREMENT) +416 FF_S302M_DEFAULT_PTS_OFFSET;417 }418 419 vidtv_s302m_write_frames(e);420 421 return e->encoder_buf;422}423 424static u32 vidtv_s302m_clear(struct vidtv_encoder *e)425{426 struct vidtv_access_unit *au = e->access_units;427 u32 count = 0;428 429 while (au) {430 count++;431 au = au->next;432 }433 434 vidtv_s302m_access_unit_destroy(e);435 memset(e->encoder_buf, 0, VIDTV_S302M_BUF_SZ);436 e->encoder_buf_offset = 0;437 438 return count;439}440 441struct vidtv_encoder442*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)443{444 u32 priv_sz = sizeof(struct vidtv_s302m_ctx);445 struct vidtv_s302m_ctx *ctx;446 struct vidtv_encoder *e;447 448 e = kzalloc(sizeof(*e), GFP_KERNEL);449 if (!e)450 return NULL;451 452 e->id = S302M;453 454 if (args.name)455 e->name = kstrdup(args.name, GFP_KERNEL);456 457 e->encoder_buf = vzalloc(VIDTV_S302M_BUF_SZ);458 if (!e->encoder_buf)459 goto out_kfree_e;460 461 e->encoder_buf_sz = VIDTV_S302M_BUF_SZ;462 e->encoder_buf_offset = 0;463 464 e->sample_count = 0;465 466 e->src_buf = (args.src_buf) ? args.src_buf : NULL;467 e->src_buf_sz = (args.src_buf) ? args.src_buf_sz : 0;468 e->src_buf_offset = 0;469 470 e->is_video_encoder = false;471 472 ctx = kzalloc(priv_sz, GFP_KERNEL);473 if (!ctx)474 goto out_kfree_buf;475 476 e->ctx = ctx;477 ctx->last_duration = 0;478 479 e->encode = vidtv_s302m_encode;480 e->clear = vidtv_s302m_clear;481 482 e->es_pid = cpu_to_be16(args.es_pid);483 e->stream_id = cpu_to_be16(PES_PRIVATE_STREAM_1);484 485 e->sync = args.sync;486 e->sampling_rate_hz = S302M_SAMPLING_RATE_HZ;487 488 e->last_sample_cb = args.last_sample_cb;489 490 e->destroy = vidtv_s302m_encoder_destroy;491 492 if (args.head) {493 while (args.head->next)494 args.head = args.head->next;495 496 args.head->next = e;497 }498 499 e->next = NULL;500 501 return e;502 503out_kfree_buf:504 vfree(e->encoder_buf);505 506out_kfree_e:507 kfree(e->name);508 kfree(e);509 return NULL;510}511 512void vidtv_s302m_encoder_destroy(struct vidtv_encoder *e)513{514 if (e->id != S302M) {515 pr_err_ratelimited("Encoder type mismatch, skipping.\n");516 return;517 }518 519 vidtv_s302m_access_unit_destroy(e);520 kfree(e->name);521 vfree(e->encoder_buf);522 kfree(e->ctx);523 kfree(e);524}525