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