xref: /linux/drivers/media/pci/saa7164/saa7164-cmd.c (revision 0cdee263bc5e7b20f657ea09f9272f50c568f35b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Driver for the NXP SAA7164 PCIe bridge
4  *
5  *  Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
6  */
7 
8 #include <linux/wait.h>
9 
10 #include "saa7164.h"
11 
saa7164_cmd_alloc_seqno(struct saa7164_dev * dev)12 static int saa7164_cmd_alloc_seqno(struct saa7164_dev *dev)
13 {
14 	int i, ret = -1;
15 
16 	mutex_lock(&dev->lock);
17 	for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) {
18 		if (dev->cmds[i].inuse == 0) {
19 			dev->cmds[i].inuse = 1;
20 			dev->cmds[i].signalled = 0;
21 			dev->cmds[i].timeout = 0;
22 			ret = dev->cmds[i].seqno;
23 			break;
24 		}
25 	}
26 	mutex_unlock(&dev->lock);
27 
28 	return ret;
29 }
30 
saa7164_cmd_free_seqno(struct saa7164_dev * dev,u8 seqno)31 static void saa7164_cmd_free_seqno(struct saa7164_dev *dev, u8 seqno)
32 {
33 	mutex_lock(&dev->lock);
34 	if ((dev->cmds[seqno].inuse == 1) &&
35 		(dev->cmds[seqno].seqno == seqno)) {
36 		dev->cmds[seqno].inuse = 0;
37 		dev->cmds[seqno].signalled = 0;
38 		dev->cmds[seqno].timeout = 0;
39 	}
40 	mutex_unlock(&dev->lock);
41 }
42 
saa7164_cmd_timeout_seqno(struct saa7164_dev * dev,u8 seqno)43 static void saa7164_cmd_timeout_seqno(struct saa7164_dev *dev, u8 seqno)
44 {
45 	mutex_lock(&dev->lock);
46 	if ((dev->cmds[seqno].inuse == 1) &&
47 		(dev->cmds[seqno].seqno == seqno)) {
48 		dev->cmds[seqno].timeout = 1;
49 	}
50 	mutex_unlock(&dev->lock);
51 }
52 
saa7164_cmd_timeout_get(struct saa7164_dev * dev,u8 seqno)53 static u32 saa7164_cmd_timeout_get(struct saa7164_dev *dev, u8 seqno)
54 {
55 	int ret = 0;
56 
57 	mutex_lock(&dev->lock);
58 	if ((dev->cmds[seqno].inuse == 1) &&
59 		(dev->cmds[seqno].seqno == seqno)) {
60 		ret = dev->cmds[seqno].timeout;
61 	}
62 	mutex_unlock(&dev->lock);
63 
64 	return ret;
65 }
66 
67 /* Commands to the f/w get marshelled to/from this code then onto the PCI
68  * -bus/c running buffer. */
saa7164_irq_dequeue(struct saa7164_dev * dev)69 int saa7164_irq_dequeue(struct saa7164_dev *dev)
70 {
71 	int ret = SAA_OK, i = 0;
72 	u32 timeout;
73 	wait_queue_head_t *q = NULL;
74 	u8 tmp[512];
75 	dprintk(DBGLVL_CMD, "%s()\n", __func__);
76 
77 	/* While any outstand message on the bus exists... */
78 	do {
79 
80 		/* Peek the msg bus */
81 		struct tmComResInfo tRsp = { 0, 0, 0, 0, 0, 0 };
82 		ret = saa7164_bus_get(dev, &tRsp, NULL, 1);
83 		if (ret != SAA_OK)
84 			break;
85 
86 		q = &dev->cmds[tRsp.seqno].wait;
87 		timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno);
88 		dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout);
89 		if (!timeout) {
90 			dprintk(DBGLVL_CMD,
91 				"%s() signalled seqno(%d) (for dequeue)\n",
92 				__func__, tRsp.seqno);
93 			dev->cmds[tRsp.seqno].signalled = 1;
94 			wake_up(q);
95 		} else {
96 			printk(KERN_ERR
97 				"%s() found timed out command on the bus\n",
98 					__func__);
99 
100 			/* Clean the bus */
101 			ret = saa7164_bus_get(dev, &tRsp, &tmp, 0);
102 			printk(KERN_ERR "%s() ret = %x\n", __func__, ret);
103 			if (ret == SAA_ERR_EMPTY)
104 				/* Someone else already fetched the response */
105 				return SAA_OK;
106 
107 			if (ret != SAA_OK)
108 				return ret;
109 		}
110 
111 		/* It's unlikely to have more than 4 or 5 pending messages,
112 		 * ensure we exit at some point regardless.
113 		 */
114 	} while (i++ < 32);
115 
116 	return ret;
117 }
118 
119 /* Commands to the f/w get marshelled to/from this code then onto the PCI
120  * -bus/c running buffer. */
saa7164_cmd_dequeue(struct saa7164_dev * dev)121 static int saa7164_cmd_dequeue(struct saa7164_dev *dev)
122 {
123 	int ret;
124 	u32 timeout;
125 	wait_queue_head_t *q = NULL;
126 	u8 tmp[512];
127 	dprintk(DBGLVL_CMD, "%s()\n", __func__);
128 
129 	while (true) {
130 
131 		struct tmComResInfo tRsp = { 0, 0, 0, 0, 0, 0 };
132 		ret = saa7164_bus_get(dev, &tRsp, NULL, 1);
133 		if (ret == SAA_ERR_EMPTY)
134 			return SAA_OK;
135 
136 		if (ret != SAA_OK)
137 			return ret;
138 
139 		q = &dev->cmds[tRsp.seqno].wait;
140 		timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno);
141 		dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout);
142 		if (timeout) {
143 			printk(KERN_ERR "found timed out command on the bus\n");
144 
145 			/* Clean the bus */
146 			ret = saa7164_bus_get(dev, &tRsp, &tmp, 0);
147 			printk(KERN_ERR "ret = %x\n", ret);
148 			if (ret == SAA_ERR_EMPTY)
149 				/* Someone else already fetched the response */
150 				return SAA_OK;
151 
152 			if (ret != SAA_OK)
153 				return ret;
154 
155 			if (tRsp.flags & PVC_CMDFLAG_CONTINUE)
156 				printk(KERN_ERR "split response\n");
157 			else
158 				saa7164_cmd_free_seqno(dev, tRsp.seqno);
159 
160 			printk(KERN_ERR " timeout continue\n");
161 			continue;
162 		}
163 
164 		dprintk(DBGLVL_CMD, "%s() signalled seqno(%d) (for dequeue)\n",
165 			__func__, tRsp.seqno);
166 		dev->cmds[tRsp.seqno].signalled = 1;
167 		wake_up(q);
168 		return SAA_OK;
169 	}
170 }
171 
saa7164_cmd_set(struct saa7164_dev * dev,struct tmComResInfo * msg,void * buf)172 static int saa7164_cmd_set(struct saa7164_dev *dev, struct tmComResInfo *msg,
173 			   void *buf)
174 {
175 	struct tmComResBusInfo *bus = &dev->bus;
176 	u8 cmd_sent;
177 	u16 size, idx;
178 	u32 cmds;
179 	void *tmp;
180 	int ret = -1;
181 
182 	if (!msg) {
183 		printk(KERN_ERR "%s() !msg\n", __func__);
184 		return SAA_ERR_BAD_PARAMETER;
185 	}
186 
187 	mutex_lock(&dev->cmds[msg->id].lock);
188 
189 	size = msg->size;
190 	cmds = size / bus->m_wMaxReqSize;
191 	if (size % bus->m_wMaxReqSize == 0)
192 		cmds -= 1;
193 
194 	cmd_sent = 0;
195 
196 	/* Split the request into smaller chunks */
197 	for (idx = 0; idx < cmds; idx++) {
198 
199 		msg->flags |= SAA_CMDFLAG_CONTINUE;
200 		msg->size = bus->m_wMaxReqSize;
201 		tmp = buf + idx * bus->m_wMaxReqSize;
202 
203 		ret = saa7164_bus_set(dev, msg, tmp);
204 		if (ret != SAA_OK) {
205 			printk(KERN_ERR "%s() set failed %d\n", __func__, ret);
206 
207 			if (cmd_sent) {
208 				ret = SAA_ERR_BUSY;
209 				goto out;
210 			}
211 			ret = SAA_ERR_OVERFLOW;
212 			goto out;
213 		}
214 		cmd_sent = 1;
215 	}
216 
217 	/* If not the last command... */
218 	if (idx != 0)
219 		msg->flags &= ~SAA_CMDFLAG_CONTINUE;
220 
221 	msg->size = size - idx * bus->m_wMaxReqSize;
222 
223 	ret = saa7164_bus_set(dev, msg, buf + idx * bus->m_wMaxReqSize);
224 	if (ret != SAA_OK) {
225 		printk(KERN_ERR "%s() set last failed %d\n", __func__, ret);
226 
227 		if (cmd_sent) {
228 			ret = SAA_ERR_BUSY;
229 			goto out;
230 		}
231 		ret = SAA_ERR_OVERFLOW;
232 		goto out;
233 	}
234 	ret = SAA_OK;
235 
236 out:
237 	mutex_unlock(&dev->cmds[msg->id].lock);
238 	return ret;
239 }
240 
241 /* Wait for a signal event, without holding a mutex. Either return TIMEOUT if
242  * the event never occurred, or SAA_OK if it was signaled during the wait.
243  */
saa7164_cmd_wait(struct saa7164_dev * dev,u8 seqno)244 static int saa7164_cmd_wait(struct saa7164_dev *dev, u8 seqno)
245 {
246 	wait_queue_head_t *q = NULL;
247 	int ret = SAA_BUS_TIMEOUT;
248 	unsigned long stamp;
249 	int r;
250 
251 	if (saa_debug >= 4)
252 		saa7164_bus_dump(dev);
253 
254 	dprintk(DBGLVL_CMD, "%s(seqno=%d)\n", __func__, seqno);
255 
256 	mutex_lock(&dev->lock);
257 	if ((dev->cmds[seqno].inuse == 1) &&
258 		(dev->cmds[seqno].seqno == seqno)) {
259 		q = &dev->cmds[seqno].wait;
260 	}
261 	mutex_unlock(&dev->lock);
262 
263 	if (q) {
264 		/* If we haven't been signalled we need to wait */
265 		if (dev->cmds[seqno].signalled == 0) {
266 			stamp = jiffies;
267 			dprintk(DBGLVL_CMD,
268 				"%s(seqno=%d) Waiting (signalled=%d)\n",
269 				__func__, seqno, dev->cmds[seqno].signalled);
270 
271 			/* Wait for signalled to be flagged or timeout */
272 			/* In a highly stressed system this can easily extend
273 			 * into multiple seconds before the deferred worker
274 			 * is scheduled, and we're woken up via signal.
275 			 * We typically are signalled in < 50ms but it can
276 			 * take MUCH longer.
277 			 */
278 			wait_event_timeout(*q, dev->cmds[seqno].signalled,
279 				(HZ * waitsecs));
280 			r = time_before(jiffies, stamp + (HZ * waitsecs));
281 			if (r)
282 				ret = SAA_OK;
283 			else
284 				saa7164_cmd_timeout_seqno(dev, seqno);
285 
286 			dprintk(DBGLVL_CMD, "%s(seqno=%d) Waiting res = %d (signalled=%d)\n",
287 				__func__, seqno, r,
288 				dev->cmds[seqno].signalled);
289 		} else
290 			ret = SAA_OK;
291 	} else
292 		printk(KERN_ERR "%s(seqno=%d) seqno is invalid\n",
293 			__func__, seqno);
294 
295 	return ret;
296 }
297 
saa7164_cmd_send(struct saa7164_dev * dev,u8 id,enum tmComResCmd command,u16 controlselector,u16 size,void * buf)298 int saa7164_cmd_send(struct saa7164_dev *dev, u8 id, enum tmComResCmd command,
299 	u16 controlselector, u16 size, void *buf)
300 {
301 	struct tmComResInfo command_t, *pcommand_t;
302 	struct tmComResInfo response_t, *presponse_t;
303 	u8 errdata[256];
304 	u16 resp_dsize;
305 	u16 data_recd;
306 	u32 loop;
307 	int ret;
308 	int safety = 0;
309 
310 	dprintk(DBGLVL_CMD, "%s(unitid = %s (%d) , command = 0x%x, sel = 0x%x)\n",
311 		__func__, saa7164_unitid_name(dev, id), id,
312 		command, controlselector);
313 
314 	if ((size == 0) || (buf == NULL)) {
315 		printk(KERN_ERR "%s() Invalid param\n", __func__);
316 		return SAA_ERR_BAD_PARAMETER;
317 	}
318 
319 	/* Prepare some basic command/response structures */
320 	memset(&command_t, 0, sizeof(command_t));
321 	memset(&response_t, 0, sizeof(response_t));
322 	pcommand_t = &command_t;
323 	presponse_t = &response_t;
324 	command_t.id = id;
325 	command_t.command = command;
326 	command_t.controlselector = controlselector;
327 	command_t.size = size;
328 
329 	/* Allocate a unique sequence number */
330 	ret = saa7164_cmd_alloc_seqno(dev);
331 	if (ret < 0) {
332 		printk(KERN_ERR "%s() No free sequences\n", __func__);
333 		ret = SAA_ERR_NO_RESOURCES;
334 		goto out;
335 	}
336 
337 	command_t.seqno = (u8)ret;
338 
339 	/* Send Command */
340 	resp_dsize = size;
341 	pcommand_t->size = size;
342 
343 	dprintk(DBGLVL_CMD, "%s() pcommand_t.seqno = %d\n",
344 		__func__, pcommand_t->seqno);
345 
346 	dprintk(DBGLVL_CMD, "%s() pcommand_t.size = %d\n",
347 		__func__, pcommand_t->size);
348 
349 	ret = saa7164_cmd_set(dev, pcommand_t, buf);
350 	if (ret != SAA_OK) {
351 		printk(KERN_ERR "%s() set command failed %d\n", __func__, ret);
352 
353 		if (ret != SAA_ERR_BUSY)
354 			saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
355 		else
356 			/* Flag a timeout, because at least one
357 			 * command was sent */
358 			saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno);
359 
360 		goto out;
361 	}
362 
363 	/* With split responses we have to collect the msgs piece by piece */
364 	data_recd = 0;
365 	loop = 1;
366 	while (loop) {
367 		dprintk(DBGLVL_CMD, "%s() loop\n", __func__);
368 
369 		ret = saa7164_cmd_wait(dev, pcommand_t->seqno);
370 		dprintk(DBGLVL_CMD, "%s() loop ret = %d\n", __func__, ret);
371 
372 		/* if power is down and this is not a power command ... */
373 
374 		if (ret == SAA_BUS_TIMEOUT) {
375 			printk(KERN_ERR "Event timed out\n");
376 			saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno);
377 			return ret;
378 		}
379 
380 		if (ret != SAA_OK) {
381 			printk(KERN_ERR "spurious error\n");
382 			return ret;
383 		}
384 
385 		/* Peek response */
386 		ret = saa7164_bus_get(dev, presponse_t, NULL, 1);
387 		if (ret == SAA_ERR_EMPTY) {
388 			dprintk(4, "%s() SAA_ERR_EMPTY\n", __func__);
389 			continue;
390 		}
391 		if (ret != SAA_OK) {
392 			printk(KERN_ERR "peek failed\n");
393 			return ret;
394 		}
395 
396 		dprintk(DBGLVL_CMD, "%s() presponse_t->seqno = %d\n",
397 			__func__, presponse_t->seqno);
398 
399 		dprintk(DBGLVL_CMD, "%s() presponse_t->flags = 0x%x\n",
400 			__func__, presponse_t->flags);
401 
402 		dprintk(DBGLVL_CMD, "%s() presponse_t->size = %d\n",
403 			__func__, presponse_t->size);
404 
405 		/* Check if the response was for our command */
406 		if (presponse_t->seqno != pcommand_t->seqno) {
407 
408 			dprintk(DBGLVL_CMD,
409 				"wrong event: seqno = %d, expected seqno = %d, will dequeue regardless\n",
410 				presponse_t->seqno, pcommand_t->seqno);
411 
412 			ret = saa7164_cmd_dequeue(dev);
413 			if (ret != SAA_OK) {
414 				printk(KERN_ERR "dequeue failed, ret = %d\n",
415 					ret);
416 				if (safety++ > 16) {
417 					printk(KERN_ERR
418 					"dequeue exceeded, safety exit\n");
419 					return SAA_ERR_BUSY;
420 				}
421 			}
422 
423 			continue;
424 		}
425 
426 		if ((presponse_t->flags & PVC_RESPONSEFLAG_ERROR) != 0) {
427 
428 			memset(&errdata[0], 0, sizeof(errdata));
429 
430 			ret = saa7164_bus_get(dev, presponse_t, &errdata[0], 0);
431 			if (ret != SAA_OK) {
432 				printk(KERN_ERR "get error(2)\n");
433 				return ret;
434 			}
435 
436 			saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
437 
438 			dprintk(DBGLVL_CMD, "%s() errdata %02x%02x%02x%02x\n",
439 				__func__, errdata[0], errdata[1], errdata[2],
440 				errdata[3]);
441 
442 			/* Map error codes */
443 			dprintk(DBGLVL_CMD, "%s() cmd, error code  = 0x%x\n",
444 				__func__, errdata[0]);
445 
446 			switch (errdata[0]) {
447 			case PVC_ERRORCODE_INVALID_COMMAND:
448 				dprintk(DBGLVL_CMD, "%s() INVALID_COMMAND\n",
449 					__func__);
450 				ret = SAA_ERR_INVALID_COMMAND;
451 				break;
452 			case PVC_ERRORCODE_INVALID_DATA:
453 				dprintk(DBGLVL_CMD, "%s() INVALID_DATA\n",
454 					__func__);
455 				ret = SAA_ERR_BAD_PARAMETER;
456 				break;
457 			case PVC_ERRORCODE_TIMEOUT:
458 				dprintk(DBGLVL_CMD, "%s() TIMEOUT\n", __func__);
459 				ret = SAA_ERR_TIMEOUT;
460 				break;
461 			case PVC_ERRORCODE_NAK:
462 				dprintk(DBGLVL_CMD, "%s() NAK\n", __func__);
463 				ret = SAA_ERR_NULL_PACKET;
464 				break;
465 			case PVC_ERRORCODE_UNKNOWN:
466 			case PVC_ERRORCODE_INVALID_CONTROL:
467 				dprintk(DBGLVL_CMD,
468 					"%s() UNKNOWN OR INVALID CONTROL\n",
469 					__func__);
470 				ret = SAA_ERR_NOT_SUPPORTED;
471 				break;
472 			default:
473 				dprintk(DBGLVL_CMD, "%s() UNKNOWN\n", __func__);
474 				ret = SAA_ERR_NOT_SUPPORTED;
475 			}
476 
477 			/* See of other commands are on the bus */
478 			if (saa7164_cmd_dequeue(dev) != SAA_OK)
479 				printk(KERN_ERR "dequeue(2) failed\n");
480 
481 			return ret;
482 		}
483 
484 		/* If response is invalid */
485 		if ((presponse_t->id != pcommand_t->id) ||
486 			(presponse_t->command != pcommand_t->command) ||
487 			(presponse_t->controlselector !=
488 				pcommand_t->controlselector) ||
489 			(((resp_dsize - data_recd) != presponse_t->size) &&
490 				!(presponse_t->flags & PVC_CMDFLAG_CONTINUE)) ||
491 			((resp_dsize - data_recd) < presponse_t->size)) {
492 
493 			/* Invalid */
494 			dprintk(DBGLVL_CMD, "%s() Invalid\n", __func__);
495 			ret = saa7164_bus_get(dev, presponse_t, NULL, 0);
496 			if (ret != SAA_OK) {
497 				printk(KERN_ERR "get failed\n");
498 				return ret;
499 			}
500 
501 			/* See of other commands are on the bus */
502 			if (saa7164_cmd_dequeue(dev) != SAA_OK)
503 				printk(KERN_ERR "dequeue(3) failed\n");
504 			continue;
505 		}
506 
507 		/* OK, now we're actually getting out correct response */
508 		ret = saa7164_bus_get(dev, presponse_t, buf + data_recd, 0);
509 		if (ret != SAA_OK) {
510 			printk(KERN_ERR "get failed\n");
511 			return ret;
512 		}
513 
514 		data_recd = presponse_t->size + data_recd;
515 		if (resp_dsize == data_recd) {
516 			dprintk(DBGLVL_CMD, "%s() Resp recd\n", __func__);
517 			break;
518 		}
519 
520 		/* See of other commands are on the bus */
521 		if (saa7164_cmd_dequeue(dev) != SAA_OK)
522 			printk(KERN_ERR "dequeue(3) failed\n");
523 	} /* (loop) */
524 
525 	/* Release the sequence number allocation */
526 	saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
527 
528 	/* if powerdown signal all pending commands */
529 
530 	dprintk(DBGLVL_CMD, "%s() Calling dequeue then exit\n", __func__);
531 
532 	/* See of other commands are on the bus */
533 	if (saa7164_cmd_dequeue(dev) != SAA_OK)
534 		printk(KERN_ERR "dequeue(4) failed\n");
535 
536 	ret = SAA_OK;
537 out:
538 	return ret;
539 }
540 
541