summaryrefslogtreecommitdiffstats
path: root/drivers/media/pci/tw5864/tw5864-core.c
blob: 560ff1ddcc83805b6e2248dc3083b015c262ace0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  TW5864 driver - core functions
 *
 *  Copyright (C) 2016 Bluecherry, LLC <maintainers@bluecherrydvr.com>
 */

#include <linux/init.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/sound.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/pm.h>
#include <linux/pci_ids.h>
#include <linux/jiffies.h>
#include <asm/dma.h>
#include <media/v4l2-dev.h>

#include "tw5864.h"
#include "tw5864-reg.h"

MODULE_DESCRIPTION("V4L2 driver module for tw5864-based multimedia capture & encoding devices");
MODULE_AUTHOR("Bluecherry Maintainers <maintainers@bluecherrydvr.com>");
MODULE_AUTHOR("Andrey Utkin <andrey.utkin@corp.bluecherry.net>");
MODULE_LICENSE("GPL");

/*
 * BEWARE OF KNOWN ISSUES WITH VIDEO QUALITY
 *
 * This driver was developed by Bluecherry LLC by deducing behaviour of
 * original manufacturer's driver, from both source code and execution traces.
 * It is known that there are some artifacts on output video with this driver:
 *  - on all known hardware samples: random pixels of wrong color (mostly
 *    white, red or blue) appearing and disappearing on sequences of P-frames;
 *  - on some hardware samples (known with H.264 core version e006:2800):
 *    total madness on P-frames: blocks of wrong luminance; blocks of wrong
 *    colors "creeping" across the picture.
 * There is a workaround for both issues: avoid P-frames by setting GOP size
 * to 1. To do that, run this command on device files created by this driver:
 *
 * v4l2-ctl --device /dev/videoX --set-ctrl=video_gop_size=1
 *
 * These issues are not decoding errors; all produced H.264 streams are decoded
 * properly. Streams without P-frames don't have these artifacts so it's not
 * analog-to-digital conversion issues nor internal memory errors; we conclude
 * it's internal H.264 encoder issues.
 * We cannot even check the original driver's behaviour because it has never
 * worked properly at all in our development environment. So these issues may
 * be actually related to firmware or hardware. However it may be that there's
 * just some more register settings missing in the driver which would please
 * the hardware.
 * Manufacturer didn't help much on our inquiries, but feel free to disturb
 * again the support of Intersil (owner of former Techwell).
 */

/* take first free /dev/videoX indexes by default */
static unsigned int video_nr[] = {[0 ... (TW5864_INPUTS - 1)] = -1 };

module_param_array(video_nr, int, NULL, 0444);
MODULE_PARM_DESC(video_nr, "video devices numbers array");

/*
 * Please add any new PCI IDs to: https://pci-ids.ucw.cz.  This keeps
 * the PCI ID database up to date.  Note that the entries must be
 * added under vendor 0x1797 (Techwell Inc.) as subsystem IDs.
 */
static const struct pci_device_id tw5864_pci_tbl[] = {
	{PCI_DEVICE(PCI_VENDOR_ID_TECHWELL, PCI_DEVICE_ID_TECHWELL_5864)},
	{0,}
};

void tw5864_irqmask_apply(struct tw5864_dev *dev)
{
	tw_writel(TW5864_INTR_ENABLE_L, dev->irqmask & 0xffff);
	tw_writel(TW5864_INTR_ENABLE_H, (dev->irqmask >> 16));
}

static void tw5864_interrupts_disable(struct tw5864_dev *dev)
{
	unsigned long flags;

	spin_lock_irqsave(&dev->slock, flags);
	dev->irqmask = 0;
	tw5864_irqmask_apply(dev);
	spin_unlock_irqrestore(&dev->slock, flags);
}

static void tw5864_timer_isr(struct tw5864_dev *dev);
static void tw5864_h264_isr(struct tw5864_dev *dev);

static irqreturn_t tw5864_isr(int irq, void *dev_id)
{
	struct tw5864_dev *dev = dev_id;
	u32 status;

	status = tw_readl(TW5864_INTR_STATUS_L) |
		tw_readl(TW5864_INTR_STATUS_H) << 16;
	if (!status)
		return IRQ_NONE;

	tw_writel(TW5864_INTR_CLR_L, 0xffff);
	tw_writel(TW5864_INTR_CLR_H, 0xffff);

	if (status & TW5864_INTR_VLC_DONE)
		tw5864_h264_isr(dev);

	if (status & TW5864_INTR_TIMER)
		tw5864_timer_isr(dev);

	if (!(status & (TW5864_INTR_TIMER | TW5864_INTR_VLC_DONE))) {
		dev_dbg(&dev->pci->dev, "Unknown interrupt, status 0x%08X\n",
			status);
	}

	return IRQ_HANDLED;
}

static void tw5864_h264_isr(struct tw5864_dev *dev)
{
	int channel = tw_readl(TW5864_DSP) & TW5864_DSP_ENC_CHN;
	struct tw5864_input *input = &dev->inputs[channel];
	int cur_frame_index, next_frame_index;
	struct tw5864_h264_frame *cur_frame, *next_frame;
	unsigned long flags;

	spin_lock_irqsave(&dev->slock, flags);

	cur_frame_index = dev->h264_buf_w_index;
	next_frame_index = (cur_frame_index + 1) % H264_BUF_CNT;
	cur_frame = &dev->h264_buf[cur_frame_index];
	next_frame = &dev->h264_buf[next_frame_index];

	if (next_frame_index != dev->h264_buf_r_index) {
		cur_frame->vlc_len = tw_readl(TW5864_VLC_LENGTH) << 2;
		cur_frame->checksum = tw_readl(TW5864_VLC_CRC_REG);
		cur_frame->input = input;
		cur_frame->timestamp = ktime_get_ns();
		cur_frame->seqno = input->frame_seqno;
		cur_frame->gop_seqno = input->frame_gop_seqno;

		dev->h264_buf_w_index = next_frame_index;
		tasklet_schedule(&dev->tasklet);

		cur_frame = next_frame;

		spin_lock(&input->slock);
		input->frame_seqno++;
		input->frame_gop_seqno++;
		if (input->frame_gop_seqno >= input->gop)
			input->frame_gop_seqno = 0;
		spin_unlock(&input->slock);
	} else {
		dev_err(&dev->pci->dev,
			"Skipped frame on input %d because all buffers busy\n",
			channel);
	}

	dev->encoder_busy = 0;

	spin_unlock_irqrestore(&dev->slock, flags);

	tw_writel(TW5864_VLC_STREAM_BASE_ADDR, cur_frame->vlc.dma_addr);
	tw_writel(TW5864_MV_STREAM_BASE_ADDR, cur_frame->mv.dma_addr);

	/* Additional ack for this interrupt */
	tw_writel(TW5864_VLC_DSP_INTR, 0x00000001);
	tw_writel(TW5864_PCI_INTR_STATUS, TW5864_VLC_DONE_INTR);
}

static void tw5864_input_deadline_update(struct tw5864_input *input)
{
	input->new_frame_deadline = jiffies + msecs_to_jiffies(1000);
}

static void tw5864_timer_isr(struct tw5864_dev *dev)
{
	unsigned long flags;
	int i;
	int encoder_busy;

	/* Additional ack for this interrupt */
	tw_writel(TW5864_PCI_INTR_STATUS, TW5864_TIMER_INTR);

	spin_lock_irqsave(&dev->slock, flags);
	encoder_busy = dev->encoder_busy;
	spin_unlock_irqrestore(&dev->slock, flags);

	if (encoder_busy)
		return;

	/*
	 * Traversing inputs in round-robin fashion, starting from next to the
	 * last processed one
	 */
	for (i = 0; i < TW5864_INPUTS; i++) {
		int next_input = (i + dev->next_input) % TW5864_INPUTS;
		struct tw5864_input *input = &dev->inputs[next_input];
		int raw_buf_id; /* id of internal buf with last raw frame */

		spin_lock_irqsave(&input->slock, flags);
		if (!input->enabled)
			goto next;

		/* Check if new raw frame is available */
		raw_buf_id = tw_mask_shift_readl(TW5864_SENIF_ORG_FRM_PTR1, 0x3,
						 2 * input->nr);

		if (input->buf_id != raw_buf_id) {
			input->buf_id = raw_buf_id;
			tw5864_input_deadline_update(input);
			spin_unlock_irqrestore(&input->slock, flags);

			spin_lock_irqsave(&dev->slock, flags);
			dev->encoder_busy = 1;
			dev->next_input = (next_input + 1) % TW5864_INPUTS;
			spin_unlock_irqrestore(&dev->slock, flags);

			tw5864_request_encoded_frame(input);
			break;
		}

		/* No new raw frame; check if channel is stuck */
		if (time_is_after_jiffies(input->new_frame_deadline)) {
			/* If stuck, request new raw frames again */
			tw_mask_shift_writel(TW5864_ENC_BUF_PTR_REC1, 0x3,
					     2 * input->nr, input->buf_id + 3);
			tw5864_input_deadline_update(input);
		}
next:
		spin_unlock_irqrestore(&input->slock, flags);
	}
}

static int tw5864_initdev(struct pci_dev *pci_dev,
			  const struct pci_device_id *pci_id)
{
	struct tw5864_dev *dev;
	int err;

	dev = devm_kzalloc(&pci_dev->dev, sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	snprintf(dev->name, sizeof(dev->name), "tw5864:%s", pci_name(pci_dev));

	err = v4l2_device_register(&pci_dev->dev, &dev->v4l2_dev);
	if (err)
		return err;

	/* pci init */
	dev->pci = pci_dev;
	err = pcim_enable_device(pci_dev);
	if (err) {
		dev_err(&dev->pci->dev, "pcim_enable_device() failed\n");
		goto unreg_v4l2;
	}

	pci_set_master(pci_dev);

	err = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
	if (err) {
		dev_err(&dev->pci->dev, "32 bit PCI DMA is not supported\n");
		goto unreg_v4l2;
	}

	/* get mmio */
	err = pcim_iomap_regions(pci_dev, BIT(0), dev->name);
	if (err) {
		dev_err(&dev->pci->dev, "Cannot request regions for MMIO\n");
		goto unreg_v4l2;
	}
	dev->mmio = pcim_iomap_table(pci_dev)[0];

	spin_lock_init(&dev->slock);

	dev_info(&pci_dev->dev, "TW5864 hardware version: %04x\n",
		 tw_readl(TW5864_HW_VERSION));
	dev_info(&pci_dev->dev, "TW5864 H.264 core version: %04x:%04x\n",
		 tw_readl(TW5864_H264REV),
		 tw_readl(TW5864_UNDECLARED_H264REV_PART2));

	err = tw5864_video_init(dev, video_nr);
	if (err)
		goto unreg_v4l2;

	/* get irq */
	err = devm_request_irq(&pci_dev->dev, pci_dev->irq, tw5864_isr,
			       IRQF_SHARED, "tw5864", dev);
	if (err < 0) {
		dev_err(&dev->pci->dev, "can't get IRQ %d\n", pci_dev->irq);
		goto fini_video;
	}

	dev_info(&pci_dev->dev, "Note: there are known video quality issues. For details\n");
	dev_info(&pci_dev->dev, "see the comment in drivers/media/pci/tw5864/tw5864-core.c.\n");

	return 0;

fini_video:
	tw5864_video_fini(dev);
unreg_v4l2:
	v4l2_device_unregister(&dev->v4l2_dev);
	return err;
}

static void tw5864_finidev(struct pci_dev *pci_dev)
{
	struct v4l2_device *v4l2_dev = pci_get_drvdata(pci_dev);
	struct tw5864_dev *dev =
		container_of(v4l2_dev, struct tw5864_dev, v4l2_dev);

	/* shutdown subsystems */
	tw5864_interrupts_disable(dev);

	/* unregister */
	tw5864_video_fini(dev);

	v4l2_device_unregister(&dev->v4l2_dev);
}

static struct pci_driver tw5864_pci_driver = {
	.name = "tw5864",
	.id_table = tw5864_pci_tbl,
	.probe = tw5864_initdev,
	.remove = tw5864_finidev,
};

module_pci_driver(tw5864_pci_driver);