1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * A virtual stateless decoder device for stateless uAPI development purposes.
4 *
5 * This tool's objective is to help the development and testing of userspace
6 * applications that use the V4L2 stateless API to decode media.
7 *
8 * A userspace implementation can use visl to run a decoding loop even when no
9 * hardware is available or when the kernel uAPI for the codec has not been
10 * upstreamed yet. This can reveal bugs at an early stage.
11 *
12 * This driver can also trace the contents of the V4L2 controls submitted to it.
13 * It can also dump the contents of the vb2 buffers through a debugfs
14 * interface. This is in many ways similar to the tracing infrastructure
15 * available for other popular encode/decode APIs out there and can help develop
16 * a userspace application by using another (working) one as a reference.
17 *
18 * Note that no actual decoding of video frames is performed by visl. The V4L2
19 * test pattern generator is used to write various debug information to the
20 * capture buffers instead.
21 *
22 * Copyright (C) 2022 Collabora, Ltd.
23 *
24 * Based on the vim2m driver, that is:
25 *
26 * Copyright (c) 2009-2010 Samsung Electronics Co., Ltd.
27 * Pawel Osciak, <pawel@osciak.com>
28 * Marek Szyprowski, <m.szyprowski@samsung.com>
29 *
30 * Based on the vicodec driver, that is:
31 *
32 * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
33 *
34 * Based on the Cedrus VPU driver, that is:
35 *
36 * Copyright (C) 2016 Florent Revest <florent.revest@free-electrons.com>
37 * Copyright (C) 2018 Paul Kocialkowski <paul.kocialkowski@bootlin.com>
38 * Copyright (C) 2018 Bootlin
39 */
40
41 #include <linux/debugfs.h>
42 #include <linux/module.h>
43 #include <linux/platform_device.h>
44 #include <media/v4l2-ctrls.h>
45 #include <media/v4l2-device.h>
46 #include <media/v4l2-ioctl.h>
47 #include <media/v4l2-mem2mem.h>
48
49 #include "visl.h"
50 #include "visl-dec.h"
51 #include "visl-debugfs.h"
52 #include "visl-video.h"
53
54 unsigned int visl_debug;
55 module_param(visl_debug, uint, 0644);
56 MODULE_PARM_DESC(visl_debug, " activates debug info");
57
58 unsigned int visl_transtime_ms;
59 module_param(visl_transtime_ms, uint, 0644);
60 MODULE_PARM_DESC(visl_transtime_ms, " simulated process time in milliseconds.");
61
62 /*
63 * dprintk can be slow through serial. This lets one limit the tracing to a
64 * particular number of frames
65 */
66 int visl_dprintk_frame_start = -1;
67 module_param(visl_dprintk_frame_start, int, 0);
68 MODULE_PARM_DESC(visl_dprintk_frame_start,
69 " a frame number to start tracing with dprintk");
70
71 unsigned int visl_dprintk_nframes;
72 module_param(visl_dprintk_nframes, uint, 0);
73 MODULE_PARM_DESC(visl_dprintk_nframes,
74 " the number of frames to trace with dprintk");
75
76 bool keep_bitstream_buffers;
77 module_param(keep_bitstream_buffers, bool, false);
78 MODULE_PARM_DESC(keep_bitstream_buffers,
79 " keep bitstream buffers in debugfs after streaming is stopped");
80
81 int bitstream_trace_frame_start = -1;
82 module_param(bitstream_trace_frame_start, int, 0);
83 MODULE_PARM_DESC(bitstream_trace_frame_start,
84 " a frame number to start dumping the bitstream through debugfs");
85
86 unsigned int bitstream_trace_nframes;
87 module_param(bitstream_trace_nframes, uint, 0);
88 MODULE_PARM_DESC(bitstream_trace_nframes,
89 " the number of frames to dump the bitstream through debugfs");
90
91 static const struct visl_ctrl_desc visl_fwht_ctrl_descs[] = {
92 {
93 .cfg.id = V4L2_CID_STATELESS_FWHT_PARAMS,
94 },
95 };
96
97 const struct visl_ctrls visl_fwht_ctrls = {
98 .ctrls = visl_fwht_ctrl_descs,
99 .num_ctrls = ARRAY_SIZE(visl_fwht_ctrl_descs)
100 };
101
102 static const struct visl_ctrl_desc visl_mpeg2_ctrl_descs[] = {
103 {
104 .cfg.id = V4L2_CID_STATELESS_MPEG2_SEQUENCE,
105 },
106 {
107 .cfg.id = V4L2_CID_STATELESS_MPEG2_PICTURE,
108 },
109 {
110 .cfg.id = V4L2_CID_STATELESS_MPEG2_QUANTISATION,
111 },
112 };
113
114 const struct visl_ctrls visl_mpeg2_ctrls = {
115 .ctrls = visl_mpeg2_ctrl_descs,
116 .num_ctrls = ARRAY_SIZE(visl_mpeg2_ctrl_descs),
117 };
118
119 static const struct visl_ctrl_desc visl_vp8_ctrl_descs[] = {
120 {
121 .cfg.id = V4L2_CID_STATELESS_VP8_FRAME,
122 },
123 };
124
125 const struct visl_ctrls visl_vp8_ctrls = {
126 .ctrls = visl_vp8_ctrl_descs,
127 .num_ctrls = ARRAY_SIZE(visl_vp8_ctrl_descs),
128 };
129
130 static const struct visl_ctrl_desc visl_vp9_ctrl_descs[] = {
131 {
132 .cfg.id = V4L2_CID_STATELESS_VP9_FRAME,
133 },
134 {
135 .cfg.id = V4L2_CID_STATELESS_VP9_COMPRESSED_HDR,
136 },
137 };
138
139 const struct visl_ctrls visl_vp9_ctrls = {
140 .ctrls = visl_vp9_ctrl_descs,
141 .num_ctrls = ARRAY_SIZE(visl_vp9_ctrl_descs),
142 };
143
144 static const struct visl_ctrl_desc visl_h264_ctrl_descs[] = {
145 {
146 .cfg.id = V4L2_CID_STATELESS_H264_DECODE_PARAMS,
147 },
148 {
149 .cfg.id = V4L2_CID_STATELESS_H264_SPS,
150 },
151 {
152 .cfg.id = V4L2_CID_STATELESS_H264_PPS,
153 },
154 {
155 .cfg.id = V4L2_CID_STATELESS_H264_SCALING_MATRIX,
156 },
157 {
158 .cfg.id = V4L2_CID_STATELESS_H264_DECODE_MODE,
159 },
160 {
161 .cfg.id = V4L2_CID_STATELESS_H264_START_CODE,
162 },
163 {
164 .cfg.id = V4L2_CID_STATELESS_H264_SLICE_PARAMS,
165 },
166 {
167 .cfg.id = V4L2_CID_STATELESS_H264_PRED_WEIGHTS,
168 },
169 };
170
171 const struct visl_ctrls visl_h264_ctrls = {
172 .ctrls = visl_h264_ctrl_descs,
173 .num_ctrls = ARRAY_SIZE(visl_h264_ctrl_descs),
174 };
175
176 static const struct visl_ctrl_desc visl_hevc_ctrl_descs[] = {
177 {
178 .cfg.id = V4L2_CID_STATELESS_HEVC_SPS,
179 },
180 {
181 .cfg.id = V4L2_CID_STATELESS_HEVC_PPS,
182 },
183 {
184 .cfg.id = V4L2_CID_STATELESS_HEVC_SLICE_PARAMS,
185 /* The absolute maximum for level > 6 */
186 .cfg.dims = { 600 },
187 },
188 {
189 .cfg.id = V4L2_CID_STATELESS_HEVC_SCALING_MATRIX,
190 },
191 {
192 .cfg.id = V4L2_CID_STATELESS_HEVC_DECODE_PARAMS,
193 },
194 {
195 .cfg.id = V4L2_CID_STATELESS_HEVC_DECODE_MODE,
196 },
197 {
198 .cfg.id = V4L2_CID_STATELESS_HEVC_START_CODE,
199 },
200 {
201 .cfg.id = V4L2_CID_STATELESS_HEVC_ENTRY_POINT_OFFSETS,
202 .cfg.dims = { 256 },
203 .cfg.max = 0xffffffff,
204 .cfg.step = 1,
205 },
206
207 };
208
209 const struct visl_ctrls visl_hevc_ctrls = {
210 .ctrls = visl_hevc_ctrl_descs,
211 .num_ctrls = ARRAY_SIZE(visl_hevc_ctrl_descs),
212 };
213
214 static const struct visl_ctrl_desc visl_av1_ctrl_descs[] = {
215 {
216 .cfg.id = V4L2_CID_STATELESS_AV1_FRAME,
217 },
218 {
219 .cfg.id = V4L2_CID_STATELESS_AV1_TILE_GROUP_ENTRY,
220 .cfg.dims = { V4L2_AV1_MAX_TILE_COUNT },
221 },
222 {
223 .cfg.id = V4L2_CID_STATELESS_AV1_SEQUENCE,
224 },
225 {
226 .cfg.id = V4L2_CID_STATELESS_AV1_FILM_GRAIN,
227 },
228 };
229
230 const struct visl_ctrls visl_av1_ctrls = {
231 .ctrls = visl_av1_ctrl_descs,
232 .num_ctrls = ARRAY_SIZE(visl_av1_ctrl_descs),
233 };
234
visl_find_control(struct visl_ctx * ctx,u32 id)235 struct v4l2_ctrl *visl_find_control(struct visl_ctx *ctx, u32 id)
236 {
237 struct v4l2_ctrl_handler *hdl = &ctx->hdl;
238
239 return v4l2_ctrl_find(hdl, id);
240 }
241
visl_find_control_data(struct visl_ctx * ctx,u32 id)242 void *visl_find_control_data(struct visl_ctx *ctx, u32 id)
243 {
244 struct v4l2_ctrl *ctrl;
245
246 ctrl = visl_find_control(ctx, id);
247 if (ctrl)
248 return ctrl->p_cur.p;
249
250 return NULL;
251 }
252
visl_control_num_elems(struct visl_ctx * ctx,u32 id)253 u32 visl_control_num_elems(struct visl_ctx *ctx, u32 id)
254 {
255 struct v4l2_ctrl *ctrl;
256
257 ctrl = visl_find_control(ctx, id);
258 if (ctrl)
259 return ctrl->elems;
260
261 return 0;
262 }
263
visl_device_release(struct video_device * vdev)264 static void visl_device_release(struct video_device *vdev)
265 {
266 struct visl_dev *dev = container_of(vdev, struct visl_dev, vfd);
267
268 v4l2_device_unregister(&dev->v4l2_dev);
269 v4l2_m2m_release(dev->m2m_dev);
270 media_device_cleanup(&dev->mdev);
271 visl_debugfs_deinit(dev);
272 kfree(dev);
273 }
274
275 #define VISL_CONTROLS_COUNT ARRAY_SIZE(visl_controls)
276
visl_init_ctrls(struct visl_ctx * ctx)277 static int visl_init_ctrls(struct visl_ctx *ctx)
278 {
279 struct visl_dev *dev = ctx->dev;
280 struct v4l2_ctrl_handler *hdl = &ctx->hdl;
281 unsigned int ctrl_cnt = 0;
282 unsigned int i;
283 unsigned int j;
284 const struct visl_ctrls *ctrls;
285
286 for (i = 0; i < num_coded_fmts; i++)
287 ctrl_cnt += visl_coded_fmts[i].ctrls->num_ctrls;
288
289 v4l2_ctrl_handler_init(hdl, ctrl_cnt);
290
291 for (i = 0; i < num_coded_fmts; i++) {
292 ctrls = visl_coded_fmts[i].ctrls;
293 for (j = 0; j < ctrls->num_ctrls; j++)
294 v4l2_ctrl_new_custom(hdl, &ctrls->ctrls[j].cfg, NULL);
295 }
296
297 if (hdl->error) {
298 v4l2_err(&dev->v4l2_dev,
299 "Failed to initialize control handler\n");
300 v4l2_ctrl_handler_free(hdl);
301 return hdl->error;
302 }
303
304 ctx->fh.ctrl_handler = hdl;
305 v4l2_ctrl_handler_setup(hdl);
306
307 return 0;
308 }
309
visl_open(struct file * file)310 static int visl_open(struct file *file)
311 {
312 struct visl_dev *dev = video_drvdata(file);
313 struct visl_ctx *ctx = NULL;
314 int rc = 0;
315
316 if (mutex_lock_interruptible(&dev->dev_mutex))
317 return -ERESTARTSYS;
318 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
319 if (!ctx) {
320 rc = -ENOMEM;
321 goto unlock;
322 }
323
324 ctx->tpg_str_buf = kzalloc(TPG_STR_BUF_SZ, GFP_KERNEL);
325
326 v4l2_fh_init(&ctx->fh, video_devdata(file));
327 file->private_data = &ctx->fh;
328 ctx->dev = dev;
329
330 rc = visl_init_ctrls(ctx);
331 if (rc)
332 goto free_ctx;
333
334 ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &visl_queue_init);
335
336 mutex_init(&ctx->vb_mutex);
337
338 if (IS_ERR(ctx->fh.m2m_ctx)) {
339 rc = PTR_ERR(ctx->fh.m2m_ctx);
340 goto free_hdl;
341 }
342
343 rc = visl_set_default_format(ctx);
344 if (rc)
345 goto free_m2m_ctx;
346
347 v4l2_fh_add(&ctx->fh);
348
349 dprintk(dev, "Created instance: %p, m2m_ctx: %p\n",
350 ctx, ctx->fh.m2m_ctx);
351
352 mutex_unlock(&dev->dev_mutex);
353 return rc;
354
355 free_m2m_ctx:
356 v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
357 free_hdl:
358 v4l2_ctrl_handler_free(&ctx->hdl);
359 v4l2_fh_exit(&ctx->fh);
360 free_ctx:
361 kfree(ctx->tpg_str_buf);
362 kfree(ctx);
363 unlock:
364 mutex_unlock(&dev->dev_mutex);
365 return rc;
366 }
367
visl_release(struct file * file)368 static int visl_release(struct file *file)
369 {
370 struct visl_dev *dev = video_drvdata(file);
371 struct visl_ctx *ctx = visl_file_to_ctx(file);
372
373 dprintk(dev, "Releasing instance %p\n", ctx);
374
375 tpg_free(&ctx->tpg);
376 v4l2_fh_del(&ctx->fh);
377 v4l2_fh_exit(&ctx->fh);
378 v4l2_ctrl_handler_free(&ctx->hdl);
379 mutex_lock(&dev->dev_mutex);
380 v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
381 mutex_unlock(&dev->dev_mutex);
382
383 kfree(ctx->tpg_str_buf);
384 kfree(ctx);
385
386 return 0;
387 }
388
389 static const struct v4l2_file_operations visl_fops = {
390 .owner = THIS_MODULE,
391 .open = visl_open,
392 .release = visl_release,
393 .poll = v4l2_m2m_fop_poll,
394 .unlocked_ioctl = video_ioctl2,
395 .mmap = v4l2_m2m_fop_mmap,
396 };
397
398 static const struct video_device visl_videodev = {
399 .name = VISL_NAME,
400 .vfl_dir = VFL_DIR_M2M,
401 .fops = &visl_fops,
402 .ioctl_ops = &visl_ioctl_ops,
403 .minor = -1,
404 .release = visl_device_release,
405 .device_caps = V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_STREAMING,
406 };
407
408 static const struct v4l2_m2m_ops visl_m2m_ops = {
409 .device_run = visl_device_run,
410 };
411
412 static const struct media_device_ops visl_m2m_media_ops = {
413 .req_validate = visl_request_validate,
414 .req_queue = v4l2_m2m_request_queue,
415 };
416
visl_probe(struct platform_device * pdev)417 static int visl_probe(struct platform_device *pdev)
418 {
419 struct visl_dev *dev;
420 struct video_device *vfd;
421 int ret;
422 int rc;
423
424 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
425 if (!dev)
426 return -ENOMEM;
427
428 ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
429 if (ret)
430 goto error_visl_dev;
431
432 mutex_init(&dev->dev_mutex);
433
434 dev->vfd = visl_videodev;
435 vfd = &dev->vfd;
436 vfd->lock = &dev->dev_mutex;
437 vfd->v4l2_dev = &dev->v4l2_dev;
438
439 video_set_drvdata(vfd, dev);
440
441 platform_set_drvdata(pdev, dev);
442
443 dev->m2m_dev = v4l2_m2m_init(&visl_m2m_ops);
444 if (IS_ERR(dev->m2m_dev)) {
445 v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
446 ret = PTR_ERR(dev->m2m_dev);
447 dev->m2m_dev = NULL;
448 goto error_dev;
449 }
450
451 dev->mdev.dev = &pdev->dev;
452 strscpy(dev->mdev.model, "visl", sizeof(dev->mdev.model));
453 strscpy(dev->mdev.bus_info, "platform:visl",
454 sizeof(dev->mdev.bus_info));
455 media_device_init(&dev->mdev);
456 dev->mdev.ops = &visl_m2m_media_ops;
457 dev->v4l2_dev.mdev = &dev->mdev;
458
459 ret = video_register_device(vfd, VFL_TYPE_VIDEO, -1);
460 if (ret) {
461 v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
462 goto error_m2m;
463 }
464
465 v4l2_info(&dev->v4l2_dev,
466 "Device registered as /dev/video%d\n", vfd->num);
467
468 ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
469 MEDIA_ENT_F_PROC_VIDEO_DECODER);
470 if (ret) {
471 v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
472 goto error_v4l2;
473 }
474
475 ret = media_device_register(&dev->mdev);
476 if (ret) {
477 v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
478 goto error_m2m_mc;
479 }
480
481 rc = visl_debugfs_init(dev);
482 if (rc)
483 dprintk(dev, "visl_debugfs_init failed: %d\n"
484 "Continuing without debugfs support\n", rc);
485
486 return 0;
487
488 error_m2m_mc:
489 v4l2_m2m_unregister_media_controller(dev->m2m_dev);
490 error_v4l2:
491 video_unregister_device(&dev->vfd);
492 /* visl_device_release called by video_unregister_device to release various objects */
493 return ret;
494 error_m2m:
495 v4l2_m2m_release(dev->m2m_dev);
496 error_dev:
497 v4l2_device_unregister(&dev->v4l2_dev);
498 error_visl_dev:
499 kfree(dev);
500
501 return ret;
502 }
503
visl_remove(struct platform_device * pdev)504 static void visl_remove(struct platform_device *pdev)
505 {
506 struct visl_dev *dev = platform_get_drvdata(pdev);
507
508 v4l2_info(&dev->v4l2_dev, "Removing " VISL_NAME);
509
510 #ifdef CONFIG_MEDIA_CONTROLLER
511 if (media_devnode_is_registered(dev->mdev.devnode)) {
512 media_device_unregister(&dev->mdev);
513 v4l2_m2m_unregister_media_controller(dev->m2m_dev);
514 }
515 #endif
516 video_unregister_device(&dev->vfd);
517 }
518
519 static struct platform_driver visl_pdrv = {
520 .probe = visl_probe,
521 .remove_new = visl_remove,
522 .driver = {
523 .name = VISL_NAME,
524 },
525 };
526
visl_dev_release(struct device * dev)527 static void visl_dev_release(struct device *dev) {}
528
529 static struct platform_device visl_pdev = {
530 .name = VISL_NAME,
531 .dev.release = visl_dev_release,
532 };
533
visl_exit(void)534 static void __exit visl_exit(void)
535 {
536 platform_driver_unregister(&visl_pdrv);
537 platform_device_unregister(&visl_pdev);
538 }
539
visl_init(void)540 static int __init visl_init(void)
541 {
542 int ret;
543
544 ret = platform_device_register(&visl_pdev);
545 if (ret)
546 return ret;
547
548 ret = platform_driver_register(&visl_pdrv);
549 if (ret)
550 platform_device_unregister(&visl_pdev);
551
552 return ret;
553 }
554
555 MODULE_DESCRIPTION("Virtual stateless decoder device");
556 MODULE_AUTHOR("Daniel Almeida <daniel.almeida@collabora.com>");
557 MODULE_LICENSE("GPL");
558
559 module_init(visl_init);
560 module_exit(visl_exit);
561