treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
[sfrench/cifs-2.6.git] / drivers / media / pci / tw5864 / tw5864-core.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  TW5864 driver - core functions
4  *
5  *  Copyright (C) 2016 Bluecherry, LLC <maintainers@bluecherrydvr.com>
6  */
7
8 #include <linux/init.h>
9 #include <linux/list.h>
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/kmod.h>
14 #include <linux/sound.h>
15 #include <linux/interrupt.h>
16 #include <linux/delay.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/pm.h>
19 #include <linux/pci_ids.h>
20 #include <linux/jiffies.h>
21 #include <asm/dma.h>
22 #include <media/v4l2-dev.h>
23
24 #include "tw5864.h"
25 #include "tw5864-reg.h"
26
27 MODULE_DESCRIPTION("V4L2 driver module for tw5864-based multimedia capture & encoding devices");
28 MODULE_AUTHOR("Bluecherry Maintainers <maintainers@bluecherrydvr.com>");
29 MODULE_AUTHOR("Andrey Utkin <andrey.utkin@corp.bluecherry.net>");
30 MODULE_LICENSE("GPL");
31
32 /*
33  * BEWARE OF KNOWN ISSUES WITH VIDEO QUALITY
34  *
35  * This driver was developed by Bluecherry LLC by deducing behaviour of
36  * original manufacturer's driver, from both source code and execution traces.
37  * It is known that there are some artifacts on output video with this driver:
38  *  - on all known hardware samples: random pixels of wrong color (mostly
39  *    white, red or blue) appearing and disappearing on sequences of P-frames;
40  *  - on some hardware samples (known with H.264 core version e006:2800):
41  *    total madness on P-frames: blocks of wrong luminance; blocks of wrong
42  *    colors "creeping" across the picture.
43  * There is a workaround for both issues: avoid P-frames by setting GOP size
44  * to 1. To do that, run this command on device files created by this driver:
45  *
46  * v4l2-ctl --device /dev/videoX --set-ctrl=video_gop_size=1
47  *
48  * These issues are not decoding errors; all produced H.264 streams are decoded
49  * properly. Streams without P-frames don't have these artifacts so it's not
50  * analog-to-digital conversion issues nor internal memory errors; we conclude
51  * it's internal H.264 encoder issues.
52  * We cannot even check the original driver's behaviour because it has never
53  * worked properly at all in our development environment. So these issues may
54  * be actually related to firmware or hardware. However it may be that there's
55  * just some more register settings missing in the driver which would please
56  * the hardware.
57  * Manufacturer didn't help much on our inquiries, but feel free to disturb
58  * again the support of Intersil (owner of former Techwell).
59  */
60
61 /* take first free /dev/videoX indexes by default */
62 static unsigned int video_nr[] = {[0 ... (TW5864_INPUTS - 1)] = -1 };
63
64 module_param_array(video_nr, int, NULL, 0444);
65 MODULE_PARM_DESC(video_nr, "video devices numbers array");
66
67 /*
68  * Please add any new PCI IDs to: http://pci-ids.ucw.cz.  This keeps
69  * the PCI ID database up to date.  Note that the entries must be
70  * added under vendor 0x1797 (Techwell Inc.) as subsystem IDs.
71  */
72 static const struct pci_device_id tw5864_pci_tbl[] = {
73         {PCI_DEVICE(PCI_VENDOR_ID_TECHWELL, PCI_DEVICE_ID_TECHWELL_5864)},
74         {0,}
75 };
76
77 void tw5864_irqmask_apply(struct tw5864_dev *dev)
78 {
79         tw_writel(TW5864_INTR_ENABLE_L, dev->irqmask & 0xffff);
80         tw_writel(TW5864_INTR_ENABLE_H, (dev->irqmask >> 16));
81 }
82
83 static void tw5864_interrupts_disable(struct tw5864_dev *dev)
84 {
85         unsigned long flags;
86
87         spin_lock_irqsave(&dev->slock, flags);
88         dev->irqmask = 0;
89         tw5864_irqmask_apply(dev);
90         spin_unlock_irqrestore(&dev->slock, flags);
91 }
92
93 static void tw5864_timer_isr(struct tw5864_dev *dev);
94 static void tw5864_h264_isr(struct tw5864_dev *dev);
95
96 static irqreturn_t tw5864_isr(int irq, void *dev_id)
97 {
98         struct tw5864_dev *dev = dev_id;
99         u32 status;
100
101         status = tw_readl(TW5864_INTR_STATUS_L) |
102                 tw_readl(TW5864_INTR_STATUS_H) << 16;
103         if (!status)
104                 return IRQ_NONE;
105
106         tw_writel(TW5864_INTR_CLR_L, 0xffff);
107         tw_writel(TW5864_INTR_CLR_H, 0xffff);
108
109         if (status & TW5864_INTR_VLC_DONE)
110                 tw5864_h264_isr(dev);
111
112         if (status & TW5864_INTR_TIMER)
113                 tw5864_timer_isr(dev);
114
115         if (!(status & (TW5864_INTR_TIMER | TW5864_INTR_VLC_DONE))) {
116                 dev_dbg(&dev->pci->dev, "Unknown interrupt, status 0x%08X\n",
117                         status);
118         }
119
120         return IRQ_HANDLED;
121 }
122
123 static void tw5864_h264_isr(struct tw5864_dev *dev)
124 {
125         int channel = tw_readl(TW5864_DSP) & TW5864_DSP_ENC_CHN;
126         struct tw5864_input *input = &dev->inputs[channel];
127         int cur_frame_index, next_frame_index;
128         struct tw5864_h264_frame *cur_frame, *next_frame;
129         unsigned long flags;
130
131         spin_lock_irqsave(&dev->slock, flags);
132
133         cur_frame_index = dev->h264_buf_w_index;
134         next_frame_index = (cur_frame_index + 1) % H264_BUF_CNT;
135         cur_frame = &dev->h264_buf[cur_frame_index];
136         next_frame = &dev->h264_buf[next_frame_index];
137
138         if (next_frame_index != dev->h264_buf_r_index) {
139                 cur_frame->vlc_len = tw_readl(TW5864_VLC_LENGTH) << 2;
140                 cur_frame->checksum = tw_readl(TW5864_VLC_CRC_REG);
141                 cur_frame->input = input;
142                 cur_frame->timestamp = ktime_get_ns();
143                 cur_frame->seqno = input->frame_seqno;
144                 cur_frame->gop_seqno = input->frame_gop_seqno;
145
146                 dev->h264_buf_w_index = next_frame_index;
147                 tasklet_schedule(&dev->tasklet);
148
149                 cur_frame = next_frame;
150
151                 spin_lock(&input->slock);
152                 input->frame_seqno++;
153                 input->frame_gop_seqno++;
154                 if (input->frame_gop_seqno >= input->gop)
155                         input->frame_gop_seqno = 0;
156                 spin_unlock(&input->slock);
157         } else {
158                 dev_err(&dev->pci->dev,
159                         "Skipped frame on input %d because all buffers busy\n",
160                         channel);
161         }
162
163         dev->encoder_busy = 0;
164
165         spin_unlock_irqrestore(&dev->slock, flags);
166
167         tw_writel(TW5864_VLC_STREAM_BASE_ADDR, cur_frame->vlc.dma_addr);
168         tw_writel(TW5864_MV_STREAM_BASE_ADDR, cur_frame->mv.dma_addr);
169
170         /* Additional ack for this interrupt */
171         tw_writel(TW5864_VLC_DSP_INTR, 0x00000001);
172         tw_writel(TW5864_PCI_INTR_STATUS, TW5864_VLC_DONE_INTR);
173 }
174
175 static void tw5864_input_deadline_update(struct tw5864_input *input)
176 {
177         input->new_frame_deadline = jiffies + msecs_to_jiffies(1000);
178 }
179
180 static void tw5864_timer_isr(struct tw5864_dev *dev)
181 {
182         unsigned long flags;
183         int i;
184         int encoder_busy;
185
186         /* Additional ack for this interrupt */
187         tw_writel(TW5864_PCI_INTR_STATUS, TW5864_TIMER_INTR);
188
189         spin_lock_irqsave(&dev->slock, flags);
190         encoder_busy = dev->encoder_busy;
191         spin_unlock_irqrestore(&dev->slock, flags);
192
193         if (encoder_busy)
194                 return;
195
196         /*
197          * Traversing inputs in round-robin fashion, starting from next to the
198          * last processed one
199          */
200         for (i = 0; i < TW5864_INPUTS; i++) {
201                 int next_input = (i + dev->next_input) % TW5864_INPUTS;
202                 struct tw5864_input *input = &dev->inputs[next_input];
203                 int raw_buf_id; /* id of internal buf with last raw frame */
204
205                 spin_lock_irqsave(&input->slock, flags);
206                 if (!input->enabled)
207                         goto next;
208
209                 /* Check if new raw frame is available */
210                 raw_buf_id = tw_mask_shift_readl(TW5864_SENIF_ORG_FRM_PTR1, 0x3,
211                                                  2 * input->nr);
212
213                 if (input->buf_id != raw_buf_id) {
214                         input->buf_id = raw_buf_id;
215                         tw5864_input_deadline_update(input);
216                         spin_unlock_irqrestore(&input->slock, flags);
217
218                         spin_lock_irqsave(&dev->slock, flags);
219                         dev->encoder_busy = 1;
220                         dev->next_input = (next_input + 1) % TW5864_INPUTS;
221                         spin_unlock_irqrestore(&dev->slock, flags);
222
223                         tw5864_request_encoded_frame(input);
224                         break;
225                 }
226
227                 /* No new raw frame; check if channel is stuck */
228                 if (time_is_after_jiffies(input->new_frame_deadline)) {
229                         /* If stuck, request new raw frames again */
230                         tw_mask_shift_writel(TW5864_ENC_BUF_PTR_REC1, 0x3,
231                                              2 * input->nr, input->buf_id + 3);
232                         tw5864_input_deadline_update(input);
233                 }
234 next:
235                 spin_unlock_irqrestore(&input->slock, flags);
236         }
237 }
238
239 static int tw5864_initdev(struct pci_dev *pci_dev,
240                           const struct pci_device_id *pci_id)
241 {
242         struct tw5864_dev *dev;
243         int err;
244
245         dev = devm_kzalloc(&pci_dev->dev, sizeof(*dev), GFP_KERNEL);
246         if (!dev)
247                 return -ENOMEM;
248
249         snprintf(dev->name, sizeof(dev->name), "tw5864:%s", pci_name(pci_dev));
250
251         err = v4l2_device_register(&pci_dev->dev, &dev->v4l2_dev);
252         if (err)
253                 return err;
254
255         /* pci init */
256         dev->pci = pci_dev;
257         err = pci_enable_device(pci_dev);
258         if (err) {
259                 dev_err(&dev->pci->dev, "pci_enable_device() failed\n");
260                 goto unreg_v4l2;
261         }
262
263         pci_set_master(pci_dev);
264
265         err = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32));
266         if (err) {
267                 dev_err(&dev->pci->dev, "32 bit PCI DMA is not supported\n");
268                 goto disable_pci;
269         }
270
271         /* get mmio */
272         err = pci_request_regions(pci_dev, dev->name);
273         if (err) {
274                 dev_err(&dev->pci->dev, "Cannot request regions for MMIO\n");
275                 goto disable_pci;
276         }
277         dev->mmio = pci_ioremap_bar(pci_dev, 0);
278         if (!dev->mmio) {
279                 err = -EIO;
280                 dev_err(&dev->pci->dev, "can't ioremap() MMIO memory\n");
281                 goto release_mmio;
282         }
283
284         spin_lock_init(&dev->slock);
285
286         dev_info(&pci_dev->dev, "TW5864 hardware version: %04x\n",
287                  tw_readl(TW5864_HW_VERSION));
288         dev_info(&pci_dev->dev, "TW5864 H.264 core version: %04x:%04x\n",
289                  tw_readl(TW5864_H264REV),
290                  tw_readl(TW5864_UNDECLARED_H264REV_PART2));
291
292         err = tw5864_video_init(dev, video_nr);
293         if (err)
294                 goto unmap_mmio;
295
296         /* get irq */
297         err = devm_request_irq(&pci_dev->dev, pci_dev->irq, tw5864_isr,
298                                IRQF_SHARED, "tw5864", dev);
299         if (err < 0) {
300                 dev_err(&dev->pci->dev, "can't get IRQ %d\n", pci_dev->irq);
301                 goto fini_video;
302         }
303
304         dev_info(&pci_dev->dev, "Note: there are known video quality issues. For details\n");
305         dev_info(&pci_dev->dev, "see the comment in drivers/media/pci/tw5864/tw5864-core.c.\n");
306
307         return 0;
308
309 fini_video:
310         tw5864_video_fini(dev);
311 unmap_mmio:
312         iounmap(dev->mmio);
313 release_mmio:
314         pci_release_regions(pci_dev);
315 disable_pci:
316         pci_disable_device(pci_dev);
317 unreg_v4l2:
318         v4l2_device_unregister(&dev->v4l2_dev);
319         return err;
320 }
321
322 static void tw5864_finidev(struct pci_dev *pci_dev)
323 {
324         struct v4l2_device *v4l2_dev = pci_get_drvdata(pci_dev);
325         struct tw5864_dev *dev =
326                 container_of(v4l2_dev, struct tw5864_dev, v4l2_dev);
327
328         /* shutdown subsystems */
329         tw5864_interrupts_disable(dev);
330
331         /* unregister */
332         tw5864_video_fini(dev);
333
334         /* release resources */
335         iounmap(dev->mmio);
336         release_mem_region(pci_resource_start(pci_dev, 0),
337                            pci_resource_len(pci_dev, 0));
338
339         v4l2_device_unregister(&dev->v4l2_dev);
340         devm_kfree(&pci_dev->dev, dev);
341 }
342
343 static struct pci_driver tw5864_pci_driver = {
344         .name = "tw5864",
345         .id_table = tw5864_pci_tbl,
346         .probe = tw5864_initdev,
347         .remove = tw5864_finidev,
348 };
349
350 module_pci_driver(tw5864_pci_driver);