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, <[email protected]>
28  * Marek Szyprowski, <[email protected]>
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 <[email protected]>
37  * Copyright (C) 2018 Paul Kocialkowski <[email protected]>
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, 0444);
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, 0444);
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, 0444);
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, 0444);
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, 0444);
88 MODULE_PARM_DESC(bitstream_trace_nframes,
89 		 " the number of frames to dump the bitstream through debugfs");
90 
91 bool tpg_verbose;
92 module_param(tpg_verbose, bool, 0644);
93 MODULE_PARM_DESC(tpg_verbose,
94 		 " add more verbose information on the generated output frames");
95 
96 static const struct visl_ctrl_desc visl_fwht_ctrl_descs[] = {
97 	{
98 		.cfg.id = V4L2_CID_STATELESS_FWHT_PARAMS,
99 	},
100 };
101 
102 const struct visl_ctrls visl_fwht_ctrls = {
103 	.ctrls = visl_fwht_ctrl_descs,
104 	.num_ctrls = ARRAY_SIZE(visl_fwht_ctrl_descs)
105 };
106 
107 static const struct visl_ctrl_desc visl_mpeg2_ctrl_descs[] = {
108 	{
109 		.cfg.id = V4L2_CID_STATELESS_MPEG2_SEQUENCE,
110 	},
111 	{
112 		.cfg.id = V4L2_CID_STATELESS_MPEG2_PICTURE,
113 	},
114 	{
115 		.cfg.id = V4L2_CID_STATELESS_MPEG2_QUANTISATION,
116 	},
117 };
118 
119 const struct visl_ctrls visl_mpeg2_ctrls = {
120 	.ctrls = visl_mpeg2_ctrl_descs,
121 	.num_ctrls = ARRAY_SIZE(visl_mpeg2_ctrl_descs),
122 };
123 
124 static const struct visl_ctrl_desc visl_vp8_ctrl_descs[] = {
125 	{
126 		.cfg.id = V4L2_CID_STATELESS_VP8_FRAME,
127 	},
128 };
129 
130 const struct visl_ctrls visl_vp8_ctrls = {
131 	.ctrls = visl_vp8_ctrl_descs,
132 	.num_ctrls = ARRAY_SIZE(visl_vp8_ctrl_descs),
133 };
134 
135 static const struct visl_ctrl_desc visl_vp9_ctrl_descs[] = {
136 	{
137 		.cfg.id = V4L2_CID_STATELESS_VP9_FRAME,
138 	},
139 	{
140 		.cfg.id = V4L2_CID_STATELESS_VP9_COMPRESSED_HDR,
141 	},
142 };
143 
144 const struct visl_ctrls visl_vp9_ctrls = {
145 	.ctrls = visl_vp9_ctrl_descs,
146 	.num_ctrls = ARRAY_SIZE(visl_vp9_ctrl_descs),
147 };
148 
149 static const struct visl_ctrl_desc visl_h264_ctrl_descs[] = {
150 	{
151 		.cfg.id = V4L2_CID_STATELESS_H264_DECODE_PARAMS,
152 	},
153 	{
154 		.cfg.id = V4L2_CID_STATELESS_H264_SPS,
155 	},
156 	{
157 		.cfg.id = V4L2_CID_STATELESS_H264_PPS,
158 	},
159 	{
160 		.cfg.id = V4L2_CID_STATELESS_H264_SCALING_MATRIX,
161 	},
162 	{
163 		.cfg.id = V4L2_CID_STATELESS_H264_DECODE_MODE,
164 		.cfg.min = V4L2_STATELESS_H264_DECODE_MODE_SLICE_BASED,
165 		.cfg.max = V4L2_STATELESS_H264_DECODE_MODE_FRAME_BASED,
166 		.cfg.def = V4L2_STATELESS_H264_DECODE_MODE_SLICE_BASED,
167 	},
168 	{
169 		.cfg.id = V4L2_CID_STATELESS_H264_START_CODE,
170 		.cfg.min = V4L2_STATELESS_H264_START_CODE_NONE,
171 		.cfg.max = V4L2_STATELESS_H264_START_CODE_ANNEX_B,
172 		.cfg.def = V4L2_STATELESS_H264_START_CODE_NONE,
173 	},
174 	{
175 		.cfg.id = V4L2_CID_STATELESS_H264_SLICE_PARAMS,
176 	},
177 	{
178 		.cfg.id = V4L2_CID_STATELESS_H264_PRED_WEIGHTS,
179 	},
180 };
181 
182 const struct visl_ctrls visl_h264_ctrls = {
183 	.ctrls = visl_h264_ctrl_descs,
184 	.num_ctrls = ARRAY_SIZE(visl_h264_ctrl_descs),
185 };
186 
187 static const struct visl_ctrl_desc visl_hevc_ctrl_descs[] = {
188 	{
189 		.cfg.id = V4L2_CID_STATELESS_HEVC_SPS,
190 	},
191 	{
192 		.cfg.id = V4L2_CID_STATELESS_HEVC_PPS,
193 	},
194 	{
195 		.cfg.id = V4L2_CID_STATELESS_HEVC_SLICE_PARAMS,
196 		/* The absolute maximum for level > 6 */
197 		.cfg.dims = { 600 },
198 	},
199 	{
200 		.cfg.id = V4L2_CID_STATELESS_HEVC_SCALING_MATRIX,
201 	},
202 	{
203 		.cfg.id = V4L2_CID_STATELESS_HEVC_DECODE_PARAMS,
204 	},
205 	{
206 		.cfg.id = V4L2_CID_STATELESS_HEVC_DECODE_MODE,
207 		.cfg.min = V4L2_STATELESS_HEVC_DECODE_MODE_SLICE_BASED,
208 		.cfg.max = V4L2_STATELESS_HEVC_DECODE_MODE_FRAME_BASED,
209 		.cfg.def = V4L2_STATELESS_HEVC_DECODE_MODE_SLICE_BASED,
210 	},
211 	{
212 		.cfg.id = V4L2_CID_STATELESS_HEVC_START_CODE,
213 		.cfg.min = V4L2_STATELESS_HEVC_START_CODE_NONE,
214 		.cfg.max = V4L2_STATELESS_HEVC_START_CODE_ANNEX_B,
215 		.cfg.def = V4L2_STATELESS_HEVC_START_CODE_NONE,
216 	},
217 	{
218 		.cfg.id = V4L2_CID_STATELESS_HEVC_ENTRY_POINT_OFFSETS,
219 		.cfg.dims = { 256 },
220 		.cfg.max = 0xffffffff,
221 		.cfg.step = 1,
222 	},
223 
224 };
225 
226 const struct visl_ctrls visl_hevc_ctrls = {
227 	.ctrls = visl_hevc_ctrl_descs,
228 	.num_ctrls = ARRAY_SIZE(visl_hevc_ctrl_descs),
229 };
230 
231 static const struct visl_ctrl_desc visl_av1_ctrl_descs[] = {
232 	{
233 		.cfg.id = V4L2_CID_STATELESS_AV1_FRAME,
234 	},
235 	{
236 		.cfg.id = V4L2_CID_STATELESS_AV1_TILE_GROUP_ENTRY,
237 		.cfg.dims = { V4L2_AV1_MAX_TILE_COUNT },
238 	},
239 	{
240 		.cfg.id = V4L2_CID_STATELESS_AV1_SEQUENCE,
241 	},
242 	{
243 		.cfg.id = V4L2_CID_STATELESS_AV1_FILM_GRAIN,
244 	},
245 };
246 
247 const struct visl_ctrls visl_av1_ctrls = {
248 	.ctrls = visl_av1_ctrl_descs,
249 	.num_ctrls = ARRAY_SIZE(visl_av1_ctrl_descs),
250 };
251 
visl_find_control(struct visl_ctx * ctx,u32 id)252 struct v4l2_ctrl *visl_find_control(struct visl_ctx *ctx, u32 id)
253 {
254 	struct v4l2_ctrl_handler *hdl = &ctx->hdl;
255 
256 	return v4l2_ctrl_find(hdl, id);
257 }
258 
visl_find_control_data(struct visl_ctx * ctx,u32 id)259 void *visl_find_control_data(struct visl_ctx *ctx, u32 id)
260 {
261 	struct v4l2_ctrl *ctrl;
262 
263 	ctrl = visl_find_control(ctx, id);
264 	if (ctrl)
265 		return ctrl->p_cur.p;
266 
267 	return NULL;
268 }
269 
visl_control_num_elems(struct visl_ctx * ctx,u32 id)270 u32 visl_control_num_elems(struct visl_ctx *ctx, u32 id)
271 {
272 	struct v4l2_ctrl *ctrl;
273 
274 	ctrl = visl_find_control(ctx, id);
275 	if (ctrl)
276 		return ctrl->elems;
277 
278 	return 0;
279 }
280 
visl_device_release(struct video_device * vdev)281 static void visl_device_release(struct video_device *vdev)
282 {
283 	struct visl_dev *dev = container_of(vdev, struct visl_dev, vfd);
284 
285 	v4l2_device_unregister(&dev->v4l2_dev);
286 	v4l2_m2m_release(dev->m2m_dev);
287 	media_device_cleanup(&dev->mdev);
288 	visl_debugfs_deinit(dev);
289 	kfree(dev);
290 }
291 
292 #define VISL_CONTROLS_COUNT	ARRAY_SIZE(visl_controls)
293 
visl_init_ctrls(struct visl_ctx * ctx)294 static int visl_init_ctrls(struct visl_ctx *ctx)
295 {
296 	struct visl_dev *dev = ctx->dev;
297 	struct v4l2_ctrl_handler *hdl = &ctx->hdl;
298 	unsigned int ctrl_cnt = 0;
299 	unsigned int i;
300 	unsigned int j;
301 	const struct visl_ctrls *ctrls;
302 
303 	for (i = 0; i < num_coded_fmts; i++)
304 		ctrl_cnt += visl_coded_fmts[i].ctrls->num_ctrls;
305 
306 	v4l2_ctrl_handler_init(hdl, ctrl_cnt);
307 
308 	for (i = 0; i < num_coded_fmts; i++) {
309 		ctrls = visl_coded_fmts[i].ctrls;
310 		for (j = 0; j < ctrls->num_ctrls; j++)
311 			v4l2_ctrl_new_custom(hdl, &ctrls->ctrls[j].cfg, NULL);
312 	}
313 
314 	if (hdl->error) {
315 		v4l2_err(&dev->v4l2_dev,
316 			 "Failed to initialize control handler\n");
317 		v4l2_ctrl_handler_free(hdl);
318 		return hdl->error;
319 	}
320 
321 	ctx->fh.ctrl_handler = hdl;
322 	v4l2_ctrl_handler_setup(hdl);
323 
324 	return 0;
325 }
326 
visl_open(struct file * file)327 static int visl_open(struct file *file)
328 {
329 	struct visl_dev *dev = video_drvdata(file);
330 	struct visl_ctx *ctx = NULL;
331 	int rc = 0;
332 
333 	if (mutex_lock_interruptible(&dev->dev_mutex))
334 		return -ERESTARTSYS;
335 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
336 	if (!ctx) {
337 		rc = -ENOMEM;
338 		goto unlock;
339 	}
340 
341 	ctx->tpg_str_buf = kzalloc(TPG_STR_BUF_SZ, GFP_KERNEL);
342 
343 	v4l2_fh_init(&ctx->fh, video_devdata(file));
344 	file->private_data = &ctx->fh;
345 	ctx->dev = dev;
346 
347 	rc = visl_init_ctrls(ctx);
348 	if (rc)
349 		goto free_ctx;
350 
351 	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &visl_queue_init);
352 
353 	mutex_init(&ctx->vb_mutex);
354 
355 	if (IS_ERR(ctx->fh.m2m_ctx)) {
356 		rc = PTR_ERR(ctx->fh.m2m_ctx);
357 		goto free_hdl;
358 	}
359 
360 	rc = visl_set_default_format(ctx);
361 	if (rc)
362 		goto free_m2m_ctx;
363 
364 	v4l2_fh_add(&ctx->fh);
365 
366 	dprintk(dev, "Created instance: %p, m2m_ctx: %p\n",
367 		ctx, ctx->fh.m2m_ctx);
368 
369 	mutex_unlock(&dev->dev_mutex);
370 	return rc;
371 
372 free_m2m_ctx:
373 	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
374 free_hdl:
375 	v4l2_ctrl_handler_free(&ctx->hdl);
376 	v4l2_fh_exit(&ctx->fh);
377 free_ctx:
378 	kfree(ctx->tpg_str_buf);
379 	kfree(ctx);
380 unlock:
381 	mutex_unlock(&dev->dev_mutex);
382 	return rc;
383 }
384 
visl_release(struct file * file)385 static int visl_release(struct file *file)
386 {
387 	struct visl_dev *dev = video_drvdata(file);
388 	struct visl_ctx *ctx = visl_file_to_ctx(file);
389 
390 	dprintk(dev, "Releasing instance %p\n", ctx);
391 
392 	tpg_free(&ctx->tpg);
393 	v4l2_fh_del(&ctx->fh);
394 	v4l2_fh_exit(&ctx->fh);
395 	v4l2_ctrl_handler_free(&ctx->hdl);
396 	mutex_lock(&dev->dev_mutex);
397 	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
398 	mutex_unlock(&dev->dev_mutex);
399 
400 	kfree(ctx->tpg_str_buf);
401 	kfree(ctx);
402 
403 	return 0;
404 }
405 
406 static const struct v4l2_file_operations visl_fops = {
407 	.owner		= THIS_MODULE,
408 	.open		= visl_open,
409 	.release	= visl_release,
410 	.poll		= v4l2_m2m_fop_poll,
411 	.unlocked_ioctl	= video_ioctl2,
412 	.mmap		= v4l2_m2m_fop_mmap,
413 };
414 
415 static const struct video_device visl_videodev = {
416 	.name		= VISL_NAME,
417 	.vfl_dir	= VFL_DIR_M2M,
418 	.fops		= &visl_fops,
419 	.ioctl_ops	= &visl_ioctl_ops,
420 	.minor		= -1,
421 	.release	= visl_device_release,
422 	.device_caps	= V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_STREAMING,
423 };
424 
425 static const struct v4l2_m2m_ops visl_m2m_ops = {
426 	.device_run	= visl_device_run,
427 };
428 
429 static const struct media_device_ops visl_m2m_media_ops = {
430 	.req_validate	= visl_request_validate,
431 	.req_queue	= v4l2_m2m_request_queue,
432 };
433 
visl_probe(struct platform_device * pdev)434 static int visl_probe(struct platform_device *pdev)
435 {
436 	struct visl_dev *dev;
437 	struct video_device *vfd;
438 	int ret;
439 	int rc;
440 
441 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
442 	if (!dev)
443 		return -ENOMEM;
444 
445 	ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
446 	if (ret)
447 		goto error_visl_dev;
448 
449 	mutex_init(&dev->dev_mutex);
450 
451 	dev->vfd = visl_videodev;
452 	vfd = &dev->vfd;
453 	vfd->lock = &dev->dev_mutex;
454 	vfd->v4l2_dev = &dev->v4l2_dev;
455 
456 	video_set_drvdata(vfd, dev);
457 
458 	platform_set_drvdata(pdev, dev);
459 
460 	dev->m2m_dev = v4l2_m2m_init(&visl_m2m_ops);
461 	if (IS_ERR(dev->m2m_dev)) {
462 		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
463 		ret = PTR_ERR(dev->m2m_dev);
464 		dev->m2m_dev = NULL;
465 		goto error_dev;
466 	}
467 
468 	dev->mdev.dev = &pdev->dev;
469 	strscpy(dev->mdev.model, "visl", sizeof(dev->mdev.model));
470 	strscpy(dev->mdev.bus_info, "platform:visl",
471 		sizeof(dev->mdev.bus_info));
472 	media_device_init(&dev->mdev);
473 	dev->mdev.ops = &visl_m2m_media_ops;
474 	dev->v4l2_dev.mdev = &dev->mdev;
475 
476 	ret = video_register_device(vfd, VFL_TYPE_VIDEO, -1);
477 	if (ret) {
478 		v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
479 		goto error_m2m;
480 	}
481 
482 	v4l2_info(&dev->v4l2_dev,
483 		  "Device registered as /dev/video%d\n", vfd->num);
484 
485 	ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
486 						 MEDIA_ENT_F_PROC_VIDEO_DECODER);
487 	if (ret) {
488 		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
489 		goto error_v4l2;
490 	}
491 
492 	ret = media_device_register(&dev->mdev);
493 	if (ret) {
494 		v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
495 		goto error_m2m_mc;
496 	}
497 
498 	rc = visl_debugfs_init(dev);
499 	if (rc)
500 		dprintk(dev, "visl_debugfs_init failed: %d\n"
501 			"Continuing without debugfs support\n", rc);
502 
503 	return 0;
504 
505 error_m2m_mc:
506 	v4l2_m2m_unregister_media_controller(dev->m2m_dev);
507 error_v4l2:
508 	video_unregister_device(&dev->vfd);
509 	/* visl_device_release called by video_unregister_device to release various objects */
510 	return ret;
511 error_m2m:
512 	v4l2_m2m_release(dev->m2m_dev);
513 error_dev:
514 	v4l2_device_unregister(&dev->v4l2_dev);
515 error_visl_dev:
516 	kfree(dev);
517 
518 	return ret;
519 }
520 
visl_remove(struct platform_device * pdev)521 static void visl_remove(struct platform_device *pdev)
522 {
523 	struct visl_dev *dev = platform_get_drvdata(pdev);
524 
525 	v4l2_info(&dev->v4l2_dev, "Removing " VISL_NAME);
526 
527 #ifdef CONFIG_MEDIA_CONTROLLER
528 	if (media_devnode_is_registered(dev->mdev.devnode)) {
529 		media_device_unregister(&dev->mdev);
530 		v4l2_m2m_unregister_media_controller(dev->m2m_dev);
531 	}
532 #endif
533 	video_unregister_device(&dev->vfd);
534 }
535 
536 static struct platform_driver visl_pdrv = {
537 	.probe		= visl_probe,
538 	.remove		= visl_remove,
539 	.driver		= {
540 		.name	= VISL_NAME,
541 	},
542 };
543 
visl_dev_release(struct device * dev)544 static void visl_dev_release(struct device *dev) {}
545 
546 static struct platform_device visl_pdev = {
547 	.name		= VISL_NAME,
548 	.dev.release	= visl_dev_release,
549 };
550 
visl_exit(void)551 static void __exit visl_exit(void)
552 {
553 	platform_driver_unregister(&visl_pdrv);
554 	platform_device_unregister(&visl_pdev);
555 }
556 
visl_init(void)557 static int __init visl_init(void)
558 {
559 	int ret;
560 
561 	ret = platform_device_register(&visl_pdev);
562 	if (ret)
563 		return ret;
564 
565 	ret = platform_driver_register(&visl_pdrv);
566 	if (ret)
567 		platform_device_unregister(&visl_pdev);
568 
569 	return ret;
570 }
571 
572 MODULE_DESCRIPTION("Virtual stateless decoder device");
573 MODULE_AUTHOR("Daniel Almeida <[email protected]>");
574 MODULE_LICENSE("GPL");
575 
576 module_init(visl_init);
577 module_exit(visl_exit);
578