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
visl_find_control(struct visl_ctx * ctx,u32 id)214 struct v4l2_ctrl *visl_find_control(struct visl_ctx *ctx, u32 id)
215 {
216 struct v4l2_ctrl_handler *hdl = &ctx->hdl;
217
218 return v4l2_ctrl_find(hdl, id);
219 }
220
visl_find_control_data(struct visl_ctx * ctx,u32 id)221 void *visl_find_control_data(struct visl_ctx *ctx, u32 id)
222 {
223 struct v4l2_ctrl *ctrl;
224
225 ctrl = visl_find_control(ctx, id);
226 if (ctrl)
227 return ctrl->p_cur.p;
228
229 return NULL;
230 }
231
visl_control_num_elems(struct visl_ctx * ctx,u32 id)232 u32 visl_control_num_elems(struct visl_ctx *ctx, u32 id)
233 {
234 struct v4l2_ctrl *ctrl;
235
236 ctrl = visl_find_control(ctx, id);
237 if (ctrl)
238 return ctrl->elems;
239
240 return 0;
241 }
242
visl_device_release(struct video_device * vdev)243 static void visl_device_release(struct video_device *vdev)
244 {
245 struct visl_dev *dev = container_of(vdev, struct visl_dev, vfd);
246
247 v4l2_device_unregister(&dev->v4l2_dev);
248 v4l2_m2m_release(dev->m2m_dev);
249 media_device_cleanup(&dev->mdev);
250 visl_debugfs_deinit(dev);
251 kfree(dev);
252 }
253
254 #define VISL_CONTROLS_COUNT ARRAY_SIZE(visl_controls)
255
visl_init_ctrls(struct visl_ctx * ctx)256 static int visl_init_ctrls(struct visl_ctx *ctx)
257 {
258 struct visl_dev *dev = ctx->dev;
259 struct v4l2_ctrl_handler *hdl = &ctx->hdl;
260 unsigned int ctrl_cnt = 0;
261 unsigned int i;
262 unsigned int j;
263 const struct visl_ctrls *ctrls;
264
265 for (i = 0; i < num_coded_fmts; i++)
266 ctrl_cnt += visl_coded_fmts[i].ctrls->num_ctrls;
267
268 v4l2_ctrl_handler_init(hdl, ctrl_cnt);
269
270 for (i = 0; i < num_coded_fmts; i++) {
271 ctrls = visl_coded_fmts[i].ctrls;
272 for (j = 0; j < ctrls->num_ctrls; j++)
273 v4l2_ctrl_new_custom(hdl, &ctrls->ctrls[j].cfg, NULL);
274 }
275
276 if (hdl->error) {
277 v4l2_err(&dev->v4l2_dev,
278 "Failed to initialize control handler\n");
279 v4l2_ctrl_handler_free(hdl);
280 return hdl->error;
281 }
282
283 ctx->fh.ctrl_handler = hdl;
284 v4l2_ctrl_handler_setup(hdl);
285
286 return 0;
287 }
288
visl_open(struct file * file)289 static int visl_open(struct file *file)
290 {
291 struct visl_dev *dev = video_drvdata(file);
292 struct visl_ctx *ctx = NULL;
293 int rc = 0;
294
295 if (mutex_lock_interruptible(&dev->dev_mutex))
296 return -ERESTARTSYS;
297 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
298 if (!ctx) {
299 rc = -ENOMEM;
300 goto unlock;
301 }
302
303 ctx->tpg_str_buf = kzalloc(TPG_STR_BUF_SZ, GFP_KERNEL);
304
305 v4l2_fh_init(&ctx->fh, video_devdata(file));
306 file->private_data = &ctx->fh;
307 ctx->dev = dev;
308
309 rc = visl_init_ctrls(ctx);
310 if (rc)
311 goto free_ctx;
312
313 ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &visl_queue_init);
314
315 mutex_init(&ctx->vb_mutex);
316
317 if (IS_ERR(ctx->fh.m2m_ctx)) {
318 rc = PTR_ERR(ctx->fh.m2m_ctx);
319 goto free_hdl;
320 }
321
322 rc = visl_set_default_format(ctx);
323 if (rc)
324 goto free_m2m_ctx;
325
326 v4l2_fh_add(&ctx->fh);
327
328 dprintk(dev, "Created instance: %p, m2m_ctx: %p\n",
329 ctx, ctx->fh.m2m_ctx);
330
331 mutex_unlock(&dev->dev_mutex);
332 return rc;
333
334 free_m2m_ctx:
335 v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
336 free_hdl:
337 v4l2_ctrl_handler_free(&ctx->hdl);
338 v4l2_fh_exit(&ctx->fh);
339 free_ctx:
340 kfree(ctx->tpg_str_buf);
341 kfree(ctx);
342 unlock:
343 mutex_unlock(&dev->dev_mutex);
344 return rc;
345 }
346
visl_release(struct file * file)347 static int visl_release(struct file *file)
348 {
349 struct visl_dev *dev = video_drvdata(file);
350 struct visl_ctx *ctx = visl_file_to_ctx(file);
351
352 dprintk(dev, "Releasing instance %p\n", ctx);
353
354 tpg_free(&ctx->tpg);
355 v4l2_fh_del(&ctx->fh);
356 v4l2_fh_exit(&ctx->fh);
357 v4l2_ctrl_handler_free(&ctx->hdl);
358 mutex_lock(&dev->dev_mutex);
359 v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
360 mutex_unlock(&dev->dev_mutex);
361
362 kfree(ctx->tpg_str_buf);
363 kfree(ctx);
364
365 return 0;
366 }
367
368 static const struct v4l2_file_operations visl_fops = {
369 .owner = THIS_MODULE,
370 .open = visl_open,
371 .release = visl_release,
372 .poll = v4l2_m2m_fop_poll,
373 .unlocked_ioctl = video_ioctl2,
374 .mmap = v4l2_m2m_fop_mmap,
375 };
376
377 static const struct video_device visl_videodev = {
378 .name = VISL_NAME,
379 .vfl_dir = VFL_DIR_M2M,
380 .fops = &visl_fops,
381 .ioctl_ops = &visl_ioctl_ops,
382 .minor = -1,
383 .release = visl_device_release,
384 .device_caps = V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_STREAMING,
385 };
386
387 static const struct v4l2_m2m_ops visl_m2m_ops = {
388 .device_run = visl_device_run,
389 };
390
391 static const struct media_device_ops visl_m2m_media_ops = {
392 .req_validate = visl_request_validate,
393 .req_queue = v4l2_m2m_request_queue,
394 };
395
visl_probe(struct platform_device * pdev)396 static int visl_probe(struct platform_device *pdev)
397 {
398 struct visl_dev *dev;
399 struct video_device *vfd;
400 int ret;
401 int rc;
402
403 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
404 if (!dev)
405 return -ENOMEM;
406
407 ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
408 if (ret)
409 goto error_visl_dev;
410
411 mutex_init(&dev->dev_mutex);
412
413 dev->vfd = visl_videodev;
414 vfd = &dev->vfd;
415 vfd->lock = &dev->dev_mutex;
416 vfd->v4l2_dev = &dev->v4l2_dev;
417
418 video_set_drvdata(vfd, dev);
419
420 platform_set_drvdata(pdev, dev);
421
422 dev->m2m_dev = v4l2_m2m_init(&visl_m2m_ops);
423 if (IS_ERR(dev->m2m_dev)) {
424 v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
425 ret = PTR_ERR(dev->m2m_dev);
426 dev->m2m_dev = NULL;
427 goto error_dev;
428 }
429
430 dev->mdev.dev = &pdev->dev;
431 strscpy(dev->mdev.model, "visl", sizeof(dev->mdev.model));
432 strscpy(dev->mdev.bus_info, "platform:visl",
433 sizeof(dev->mdev.bus_info));
434 media_device_init(&dev->mdev);
435 dev->mdev.ops = &visl_m2m_media_ops;
436 dev->v4l2_dev.mdev = &dev->mdev;
437
438 ret = video_register_device(vfd, VFL_TYPE_VIDEO, -1);
439 if (ret) {
440 v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
441 goto error_m2m;
442 }
443
444 v4l2_info(&dev->v4l2_dev,
445 "Device registered as /dev/video%d\n", vfd->num);
446
447 ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
448 MEDIA_ENT_F_PROC_VIDEO_DECODER);
449 if (ret) {
450 v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
451 goto error_v4l2;
452 }
453
454 ret = media_device_register(&dev->mdev);
455 if (ret) {
456 v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
457 goto error_m2m_mc;
458 }
459
460 rc = visl_debugfs_init(dev);
461 if (rc)
462 dprintk(dev, "visl_debugfs_init failed: %d\n"
463 "Continuing without debugfs support\n", rc);
464
465 return 0;
466
467 error_m2m_mc:
468 v4l2_m2m_unregister_media_controller(dev->m2m_dev);
469 error_v4l2:
470 video_unregister_device(&dev->vfd);
471 /* visl_device_release called by video_unregister_device to release various objects */
472 return ret;
473 error_m2m:
474 v4l2_m2m_release(dev->m2m_dev);
475 error_dev:
476 v4l2_device_unregister(&dev->v4l2_dev);
477 error_visl_dev:
478 kfree(dev);
479
480 return ret;
481 }
482
visl_remove(struct platform_device * pdev)483 static void visl_remove(struct platform_device *pdev)
484 {
485 struct visl_dev *dev = platform_get_drvdata(pdev);
486
487 v4l2_info(&dev->v4l2_dev, "Removing " VISL_NAME);
488
489 #ifdef CONFIG_MEDIA_CONTROLLER
490 if (media_devnode_is_registered(dev->mdev.devnode)) {
491 media_device_unregister(&dev->mdev);
492 v4l2_m2m_unregister_media_controller(dev->m2m_dev);
493 }
494 #endif
495 video_unregister_device(&dev->vfd);
496 }
497
498 static struct platform_driver visl_pdrv = {
499 .probe = visl_probe,
500 .remove_new = visl_remove,
501 .driver = {
502 .name = VISL_NAME,
503 },
504 };
505
visl_dev_release(struct device * dev)506 static void visl_dev_release(struct device *dev) {}
507
508 static struct platform_device visl_pdev = {
509 .name = VISL_NAME,
510 .dev.release = visl_dev_release,
511 };
512
visl_exit(void)513 static void __exit visl_exit(void)
514 {
515 platform_driver_unregister(&visl_pdrv);
516 platform_device_unregister(&visl_pdev);
517 }
518
visl_init(void)519 static int __init visl_init(void)
520 {
521 int ret;
522
523 ret = platform_device_register(&visl_pdev);
524 if (ret)
525 return ret;
526
527 ret = platform_driver_register(&visl_pdrv);
528 if (ret)
529 platform_device_unregister(&visl_pdev);
530
531 return ret;
532 }
533
534 MODULE_DESCRIPTION("Virtual stateless decoder device");
535 MODULE_AUTHOR("Daniel Almeida <daniel.almeida@collabora.com>");
536 MODULE_LICENSE("GPL");
537
538 module_init(visl_init);
539 module_exit(visl_exit);
540