1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2016-2017, Linaro Ltd
4 */
5
6 #include <linux/idr.h>
7 #include <linux/interrupt.h>
8 #include <linux/io.h>
9 #include <linux/list.h>
10 #include <linux/mfd/syscon.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14 #include <linux/of_irq.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17 #include <linux/rpmsg.h>
18 #include <linux/sizes.h>
19 #include <linux/slab.h>
20 #include <linux/workqueue.h>
21 #include <linux/mailbox_client.h>
22
23 #include "rpmsg_internal.h"
24 #include "qcom_glink_native.h"
25
26 #define GLINK_NAME_SIZE 32
27 #define GLINK_VERSION_1 1
28
29 #define RPM_GLINK_CID_MIN 1
30 #define RPM_GLINK_CID_MAX 65536
31
32 struct glink_msg {
33 __le16 cmd;
34 __le16 param1;
35 __le32 param2;
36 u8 data[];
37 } __packed;
38
39 /**
40 * struct glink_defer_cmd - deferred incoming control message
41 * @node: list node
42 * @msg: message header
43 * @data: payload of the message
44 *
45 * Copy of a received control message, to be added to @rx_queue and processed
46 * by @rx_work of @qcom_glink.
47 */
48 struct glink_defer_cmd {
49 struct list_head node;
50
51 struct glink_msg msg;
52 u8 data[];
53 };
54
55 /**
56 * struct glink_core_rx_intent - RX intent
57 * RX intent
58 *
59 * @data: pointer to the data (may be NULL for zero-copy)
60 * @id: remote or local intent ID
61 * @size: size of the original intent (do not modify)
62 * @reuse: To mark if the intent can be reused after first use
63 * @in_use: To mark if intent is already in use for the channel
64 * @offset: next write offset (initially 0)
65 * @node: list node
66 */
67 struct glink_core_rx_intent {
68 void *data;
69 u32 id;
70 size_t size;
71 bool reuse;
72 bool in_use;
73 u32 offset;
74
75 struct list_head node;
76 };
77
78 /**
79 * struct qcom_glink - driver context, relates to one remote subsystem
80 * @dev: reference to the associated struct device
81 * @mbox_client: mailbox client
82 * @mbox_chan: mailbox channel
83 * @rx_pipe: pipe object for receive FIFO
84 * @tx_pipe: pipe object for transmit FIFO
85 * @irq: IRQ for signaling incoming events
86 * @rx_work: worker for handling received control messages
87 * @rx_lock: protects the @rx_queue
88 * @rx_queue: queue of received control messages to be processed in @rx_work
89 * @tx_lock: synchronizes operations on the tx fifo
90 * @idr_lock: synchronizes @lcids and @rcids modifications
91 * @lcids: idr of all channels with a known local channel id
92 * @rcids: idr of all channels with a known remote channel id
93 * @features: remote features
94 * @intentless: flag to indicate that there is no intent
95 */
96 struct qcom_glink {
97 struct device *dev;
98
99 const char *name;
100
101 struct mbox_client mbox_client;
102 struct mbox_chan *mbox_chan;
103
104 struct qcom_glink_pipe *rx_pipe;
105 struct qcom_glink_pipe *tx_pipe;
106
107 int irq;
108
109 struct work_struct rx_work;
110 spinlock_t rx_lock;
111 struct list_head rx_queue;
112
113 spinlock_t tx_lock;
114
115 spinlock_t idr_lock;
116 struct idr lcids;
117 struct idr rcids;
118 unsigned long features;
119
120 bool intentless;
121 };
122
123 enum {
124 GLINK_STATE_CLOSED,
125 GLINK_STATE_OPENING,
126 GLINK_STATE_OPEN,
127 GLINK_STATE_CLOSING,
128 };
129
130 /**
131 * struct glink_channel - internal representation of a channel
132 * @rpdev: rpdev reference, only used for primary endpoints
133 * @ept: rpmsg endpoint this channel is associated with
134 * @glink: qcom_glink context handle
135 * @refcount: refcount for the channel object
136 * @recv_lock: guard for @ept.cb
137 * @name: unique channel name/identifier
138 * @lcid: channel id, in local space
139 * @rcid: channel id, in remote space
140 * @intent_lock: lock for protection of @liids, @riids
141 * @liids: idr of all local intents
142 * @riids: idr of all remote intents
143 * @intent_work: worker responsible for transmitting rx_done packets
144 * @done_intents: list of intents that needs to be announced rx_done
145 * @buf: receive buffer, for gathering fragments
146 * @buf_offset: write offset in @buf
147 * @buf_size: size of current @buf
148 * @open_ack: completed once remote has acked the open-request
149 * @open_req: completed once open-request has been received
150 * @intent_req_lock: Synchronises multiple intent requests
151 * @intent_req_result: Result of intent request
152 * @intent_req_comp: Completion for intent_req signalling
153 */
154 struct glink_channel {
155 struct rpmsg_endpoint ept;
156
157 struct rpmsg_device *rpdev;
158 struct qcom_glink *glink;
159
160 struct kref refcount;
161
162 spinlock_t recv_lock;
163
164 char *name;
165 unsigned int lcid;
166 unsigned int rcid;
167
168 spinlock_t intent_lock;
169 struct idr liids;
170 struct idr riids;
171 struct work_struct intent_work;
172 struct list_head done_intents;
173
174 struct glink_core_rx_intent *buf;
175 int buf_offset;
176 int buf_size;
177
178 struct completion open_ack;
179 struct completion open_req;
180
181 struct mutex intent_req_lock;
182 bool intent_req_result;
183 struct completion intent_req_comp;
184 };
185
186 #define to_glink_channel(_ept) container_of(_ept, struct glink_channel, ept)
187
188 static const struct rpmsg_endpoint_ops glink_endpoint_ops;
189
190 #define RPM_CMD_VERSION 0
191 #define RPM_CMD_VERSION_ACK 1
192 #define RPM_CMD_OPEN 2
193 #define RPM_CMD_CLOSE 3
194 #define RPM_CMD_OPEN_ACK 4
195 #define RPM_CMD_INTENT 5
196 #define RPM_CMD_RX_DONE 6
197 #define RPM_CMD_RX_INTENT_REQ 7
198 #define RPM_CMD_RX_INTENT_REQ_ACK 8
199 #define RPM_CMD_TX_DATA 9
200 #define RPM_CMD_CLOSE_ACK 11
201 #define RPM_CMD_TX_DATA_CONT 12
202 #define RPM_CMD_READ_NOTIF 13
203 #define RPM_CMD_RX_DONE_W_REUSE 14
204
205 #define GLINK_FEATURE_INTENTLESS BIT(1)
206
207 static void qcom_glink_rx_done_work(struct work_struct *work);
208
qcom_glink_alloc_channel(struct qcom_glink * glink,const char * name)209 static struct glink_channel *qcom_glink_alloc_channel(struct qcom_glink *glink,
210 const char *name)
211 {
212 struct glink_channel *channel;
213
214 channel = kzalloc(sizeof(*channel), GFP_KERNEL);
215 if (!channel)
216 return ERR_PTR(-ENOMEM);
217
218 /* Setup glink internal glink_channel data */
219 spin_lock_init(&channel->recv_lock);
220 spin_lock_init(&channel->intent_lock);
221 mutex_init(&channel->intent_req_lock);
222
223 channel->glink = glink;
224 channel->name = kstrdup(name, GFP_KERNEL);
225
226 init_completion(&channel->open_req);
227 init_completion(&channel->open_ack);
228 init_completion(&channel->intent_req_comp);
229
230 INIT_LIST_HEAD(&channel->done_intents);
231 INIT_WORK(&channel->intent_work, qcom_glink_rx_done_work);
232
233 idr_init(&channel->liids);
234 idr_init(&channel->riids);
235 kref_init(&channel->refcount);
236
237 return channel;
238 }
239
qcom_glink_channel_release(struct kref * ref)240 static void qcom_glink_channel_release(struct kref *ref)
241 {
242 struct glink_channel *channel = container_of(ref, struct glink_channel,
243 refcount);
244 struct glink_core_rx_intent *intent;
245 struct glink_core_rx_intent *tmp;
246 unsigned long flags;
247 int iid;
248
249 /* cancel pending rx_done work */
250 cancel_work_sync(&channel->intent_work);
251
252 spin_lock_irqsave(&channel->intent_lock, flags);
253 /* Free all non-reuse intents pending rx_done work */
254 list_for_each_entry_safe(intent, tmp, &channel->done_intents, node) {
255 if (!intent->reuse) {
256 kfree(intent->data);
257 kfree(intent);
258 }
259 }
260
261 idr_for_each_entry(&channel->liids, tmp, iid) {
262 kfree(tmp->data);
263 kfree(tmp);
264 }
265 idr_destroy(&channel->liids);
266
267 idr_for_each_entry(&channel->riids, tmp, iid)
268 kfree(tmp);
269 idr_destroy(&channel->riids);
270 spin_unlock_irqrestore(&channel->intent_lock, flags);
271
272 kfree(channel->name);
273 kfree(channel);
274 }
275
qcom_glink_rx_avail(struct qcom_glink * glink)276 static size_t qcom_glink_rx_avail(struct qcom_glink *glink)
277 {
278 return glink->rx_pipe->avail(glink->rx_pipe);
279 }
280
qcom_glink_rx_peak(struct qcom_glink * glink,void * data,unsigned int offset,size_t count)281 static void qcom_glink_rx_peak(struct qcom_glink *glink,
282 void *data, unsigned int offset, size_t count)
283 {
284 glink->rx_pipe->peak(glink->rx_pipe, data, offset, count);
285 }
286
qcom_glink_rx_advance(struct qcom_glink * glink,size_t count)287 static void qcom_glink_rx_advance(struct qcom_glink *glink, size_t count)
288 {
289 glink->rx_pipe->advance(glink->rx_pipe, count);
290 }
291
qcom_glink_tx_avail(struct qcom_glink * glink)292 static size_t qcom_glink_tx_avail(struct qcom_glink *glink)
293 {
294 return glink->tx_pipe->avail(glink->tx_pipe);
295 }
296
qcom_glink_tx_write(struct qcom_glink * glink,const void * hdr,size_t hlen,const void * data,size_t dlen)297 static void qcom_glink_tx_write(struct qcom_glink *glink,
298 const void *hdr, size_t hlen,
299 const void *data, size_t dlen)
300 {
301 glink->tx_pipe->write(glink->tx_pipe, hdr, hlen, data, dlen);
302 }
303
qcom_glink_tx(struct qcom_glink * glink,const void * hdr,size_t hlen,const void * data,size_t dlen,bool wait)304 static int qcom_glink_tx(struct qcom_glink *glink,
305 const void *hdr, size_t hlen,
306 const void *data, size_t dlen, bool wait)
307 {
308 unsigned int tlen = hlen + dlen;
309 unsigned long flags;
310 int ret = 0;
311
312 /* Reject packets that are too big */
313 if (tlen >= glink->tx_pipe->length)
314 return -EINVAL;
315
316 spin_lock_irqsave(&glink->tx_lock, flags);
317
318 while (qcom_glink_tx_avail(glink) < tlen) {
319 if (!wait) {
320 ret = -EAGAIN;
321 goto out;
322 }
323
324 /* Wait without holding the tx_lock */
325 spin_unlock_irqrestore(&glink->tx_lock, flags);
326
327 usleep_range(10000, 15000);
328
329 spin_lock_irqsave(&glink->tx_lock, flags);
330 }
331
332 qcom_glink_tx_write(glink, hdr, hlen, data, dlen);
333
334 mbox_send_message(glink->mbox_chan, NULL);
335 mbox_client_txdone(glink->mbox_chan, 0);
336
337 out:
338 spin_unlock_irqrestore(&glink->tx_lock, flags);
339
340 return ret;
341 }
342
qcom_glink_send_version(struct qcom_glink * glink)343 static int qcom_glink_send_version(struct qcom_glink *glink)
344 {
345 struct glink_msg msg;
346
347 msg.cmd = cpu_to_le16(RPM_CMD_VERSION);
348 msg.param1 = cpu_to_le16(GLINK_VERSION_1);
349 msg.param2 = cpu_to_le32(glink->features);
350
351 return qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
352 }
353
qcom_glink_send_version_ack(struct qcom_glink * glink)354 static void qcom_glink_send_version_ack(struct qcom_glink *glink)
355 {
356 struct glink_msg msg;
357
358 msg.cmd = cpu_to_le16(RPM_CMD_VERSION_ACK);
359 msg.param1 = cpu_to_le16(GLINK_VERSION_1);
360 msg.param2 = cpu_to_le32(glink->features);
361
362 qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
363 }
364
qcom_glink_send_open_ack(struct qcom_glink * glink,struct glink_channel * channel)365 static void qcom_glink_send_open_ack(struct qcom_glink *glink,
366 struct glink_channel *channel)
367 {
368 struct glink_msg msg;
369
370 msg.cmd = cpu_to_le16(RPM_CMD_OPEN_ACK);
371 msg.param1 = cpu_to_le16(channel->rcid);
372 msg.param2 = cpu_to_le32(0);
373
374 qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
375 }
376
qcom_glink_handle_intent_req_ack(struct qcom_glink * glink,unsigned int cid,bool granted)377 static void qcom_glink_handle_intent_req_ack(struct qcom_glink *glink,
378 unsigned int cid, bool granted)
379 {
380 struct glink_channel *channel;
381 unsigned long flags;
382
383 spin_lock_irqsave(&glink->idr_lock, flags);
384 channel = idr_find(&glink->rcids, cid);
385 spin_unlock_irqrestore(&glink->idr_lock, flags);
386 if (!channel) {
387 dev_err(glink->dev, "unable to find channel\n");
388 return;
389 }
390
391 channel->intent_req_result = granted;
392 complete(&channel->intent_req_comp);
393 }
394
395 /**
396 * qcom_glink_send_open_req() - send a RPM_CMD_OPEN request to the remote
397 * @glink: Ptr to the glink edge
398 * @channel: Ptr to the channel that the open req is sent
399 *
400 * Allocates a local channel id and sends a RPM_CMD_OPEN message to the remote.
401 * Will return with refcount held, regardless of outcome.
402 *
403 * Returns 0 on success, negative errno otherwise.
404 */
qcom_glink_send_open_req(struct qcom_glink * glink,struct glink_channel * channel)405 static int qcom_glink_send_open_req(struct qcom_glink *glink,
406 struct glink_channel *channel)
407 {
408 struct {
409 struct glink_msg msg;
410 u8 name[GLINK_NAME_SIZE];
411 } __packed req;
412 int name_len = strlen(channel->name) + 1;
413 int req_len = ALIGN(sizeof(req.msg) + name_len, 8);
414 int ret;
415 unsigned long flags;
416
417 kref_get(&channel->refcount);
418
419 spin_lock_irqsave(&glink->idr_lock, flags);
420 ret = idr_alloc_cyclic(&glink->lcids, channel,
421 RPM_GLINK_CID_MIN, RPM_GLINK_CID_MAX,
422 GFP_ATOMIC);
423 spin_unlock_irqrestore(&glink->idr_lock, flags);
424 if (ret < 0)
425 return ret;
426
427 channel->lcid = ret;
428
429 req.msg.cmd = cpu_to_le16(RPM_CMD_OPEN);
430 req.msg.param1 = cpu_to_le16(channel->lcid);
431 req.msg.param2 = cpu_to_le32(name_len);
432 strcpy(req.name, channel->name);
433
434 ret = qcom_glink_tx(glink, &req, req_len, NULL, 0, true);
435 if (ret)
436 goto remove_idr;
437
438 return 0;
439
440 remove_idr:
441 spin_lock_irqsave(&glink->idr_lock, flags);
442 idr_remove(&glink->lcids, channel->lcid);
443 channel->lcid = 0;
444 spin_unlock_irqrestore(&glink->idr_lock, flags);
445
446 return ret;
447 }
448
qcom_glink_send_close_req(struct qcom_glink * glink,struct glink_channel * channel)449 static void qcom_glink_send_close_req(struct qcom_glink *glink,
450 struct glink_channel *channel)
451 {
452 struct glink_msg req;
453
454 req.cmd = cpu_to_le16(RPM_CMD_CLOSE);
455 req.param1 = cpu_to_le16(channel->lcid);
456 req.param2 = 0;
457
458 qcom_glink_tx(glink, &req, sizeof(req), NULL, 0, true);
459 }
460
qcom_glink_send_close_ack(struct qcom_glink * glink,unsigned int rcid)461 static void qcom_glink_send_close_ack(struct qcom_glink *glink,
462 unsigned int rcid)
463 {
464 struct glink_msg req;
465
466 req.cmd = cpu_to_le16(RPM_CMD_CLOSE_ACK);
467 req.param1 = cpu_to_le16(rcid);
468 req.param2 = 0;
469
470 qcom_glink_tx(glink, &req, sizeof(req), NULL, 0, true);
471 }
472
qcom_glink_rx_done_work(struct work_struct * work)473 static void qcom_glink_rx_done_work(struct work_struct *work)
474 {
475 struct glink_channel *channel = container_of(work, struct glink_channel,
476 intent_work);
477 struct qcom_glink *glink = channel->glink;
478 struct glink_core_rx_intent *intent, *tmp;
479 struct {
480 u16 id;
481 u16 lcid;
482 u32 liid;
483 } __packed cmd;
484
485 unsigned int cid = channel->lcid;
486 unsigned int iid;
487 bool reuse;
488 unsigned long flags;
489
490 spin_lock_irqsave(&channel->intent_lock, flags);
491 list_for_each_entry_safe(intent, tmp, &channel->done_intents, node) {
492 list_del(&intent->node);
493 spin_unlock_irqrestore(&channel->intent_lock, flags);
494 iid = intent->id;
495 reuse = intent->reuse;
496
497 cmd.id = reuse ? RPM_CMD_RX_DONE_W_REUSE : RPM_CMD_RX_DONE;
498 cmd.lcid = cid;
499 cmd.liid = iid;
500
501 qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
502 if (!reuse) {
503 kfree(intent->data);
504 kfree(intent);
505 }
506 spin_lock_irqsave(&channel->intent_lock, flags);
507 }
508 spin_unlock_irqrestore(&channel->intent_lock, flags);
509 }
510
qcom_glink_rx_done(struct qcom_glink * glink,struct glink_channel * channel,struct glink_core_rx_intent * intent)511 static void qcom_glink_rx_done(struct qcom_glink *glink,
512 struct glink_channel *channel,
513 struct glink_core_rx_intent *intent)
514 {
515 /* We don't send RX_DONE to intentless systems */
516 if (glink->intentless) {
517 kfree(intent->data);
518 kfree(intent);
519 return;
520 }
521
522 /* Take it off the tree of receive intents */
523 if (!intent->reuse) {
524 spin_lock(&channel->intent_lock);
525 idr_remove(&channel->liids, intent->id);
526 spin_unlock(&channel->intent_lock);
527 }
528
529 /* Schedule the sending of a rx_done indication */
530 spin_lock(&channel->intent_lock);
531 list_add_tail(&intent->node, &channel->done_intents);
532 spin_unlock(&channel->intent_lock);
533
534 schedule_work(&channel->intent_work);
535 }
536
537 /**
538 * qcom_glink_receive_version() - receive version/features from remote system
539 *
540 * @glink: pointer to transport interface
541 * @version: remote version
542 * @features: remote features
543 *
544 * This function is called in response to a remote-initiated version/feature
545 * negotiation sequence.
546 */
qcom_glink_receive_version(struct qcom_glink * glink,u32 version,u32 features)547 static void qcom_glink_receive_version(struct qcom_glink *glink,
548 u32 version,
549 u32 features)
550 {
551 switch (version) {
552 case 0:
553 break;
554 case GLINK_VERSION_1:
555 glink->features &= features;
556 /* FALLTHROUGH */
557 default:
558 qcom_glink_send_version_ack(glink);
559 break;
560 }
561 }
562
563 /**
564 * qcom_glink_receive_version_ack() - receive negotiation ack from remote system
565 *
566 * @glink: pointer to transport interface
567 * @version: remote version response
568 * @features: remote features response
569 *
570 * This function is called in response to a local-initiated version/feature
571 * negotiation sequence and is the counter-offer from the remote side based
572 * upon the initial version and feature set requested.
573 */
qcom_glink_receive_version_ack(struct qcom_glink * glink,u32 version,u32 features)574 static void qcom_glink_receive_version_ack(struct qcom_glink *glink,
575 u32 version,
576 u32 features)
577 {
578 switch (version) {
579 case 0:
580 /* Version negotiation failed */
581 break;
582 case GLINK_VERSION_1:
583 if (features == glink->features)
584 break;
585
586 glink->features &= features;
587 /* FALLTHROUGH */
588 default:
589 qcom_glink_send_version(glink);
590 break;
591 }
592 }
593
594 /**
595 * qcom_glink_send_intent_req_ack() - convert an rx intent request ack cmd to
596 * wire format and transmit
597 * @glink: The transport to transmit on.
598 * @channel: The glink channel
599 * @granted: The request response to encode.
600 *
601 * Return: 0 on success or standard Linux error code.
602 */
qcom_glink_send_intent_req_ack(struct qcom_glink * glink,struct glink_channel * channel,bool granted)603 static int qcom_glink_send_intent_req_ack(struct qcom_glink *glink,
604 struct glink_channel *channel,
605 bool granted)
606 {
607 struct glink_msg msg;
608
609 msg.cmd = cpu_to_le16(RPM_CMD_RX_INTENT_REQ_ACK);
610 msg.param1 = cpu_to_le16(channel->lcid);
611 msg.param2 = cpu_to_le32(granted);
612
613 qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
614
615 return 0;
616 }
617
618 /**
619 * qcom_glink_advertise_intent - convert an rx intent cmd to wire format and
620 * transmit
621 * @glink: The transport to transmit on.
622 * @channel: The local channel
623 * @intent: The intent to pass on to remote.
624 *
625 * Return: 0 on success or standard Linux error code.
626 */
qcom_glink_advertise_intent(struct qcom_glink * glink,struct glink_channel * channel,struct glink_core_rx_intent * intent)627 static int qcom_glink_advertise_intent(struct qcom_glink *glink,
628 struct glink_channel *channel,
629 struct glink_core_rx_intent *intent)
630 {
631 struct command {
632 __le16 id;
633 __le16 lcid;
634 __le32 count;
635 __le32 size;
636 __le32 liid;
637 } __packed;
638 struct command cmd;
639
640 cmd.id = cpu_to_le16(RPM_CMD_INTENT);
641 cmd.lcid = cpu_to_le16(channel->lcid);
642 cmd.count = cpu_to_le32(1);
643 cmd.size = cpu_to_le32(intent->size);
644 cmd.liid = cpu_to_le32(intent->id);
645
646 qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
647
648 return 0;
649 }
650
651 static struct glink_core_rx_intent *
qcom_glink_alloc_intent(struct qcom_glink * glink,struct glink_channel * channel,size_t size,bool reuseable)652 qcom_glink_alloc_intent(struct qcom_glink *glink,
653 struct glink_channel *channel,
654 size_t size,
655 bool reuseable)
656 {
657 struct glink_core_rx_intent *intent;
658 int ret;
659 unsigned long flags;
660
661 intent = kzalloc(sizeof(*intent), GFP_KERNEL);
662 if (!intent)
663 return NULL;
664
665 intent->data = kzalloc(size, GFP_KERNEL);
666 if (!intent->data)
667 goto free_intent;
668
669 spin_lock_irqsave(&channel->intent_lock, flags);
670 ret = idr_alloc_cyclic(&channel->liids, intent, 1, -1, GFP_ATOMIC);
671 if (ret < 0) {
672 spin_unlock_irqrestore(&channel->intent_lock, flags);
673 goto free_data;
674 }
675 spin_unlock_irqrestore(&channel->intent_lock, flags);
676
677 intent->id = ret;
678 intent->size = size;
679 intent->reuse = reuseable;
680
681 return intent;
682
683 free_data:
684 kfree(intent->data);
685 free_intent:
686 kfree(intent);
687 return NULL;
688 }
689
qcom_glink_handle_rx_done(struct qcom_glink * glink,u32 cid,uint32_t iid,bool reuse)690 static void qcom_glink_handle_rx_done(struct qcom_glink *glink,
691 u32 cid, uint32_t iid,
692 bool reuse)
693 {
694 struct glink_core_rx_intent *intent;
695 struct glink_channel *channel;
696 unsigned long flags;
697
698 spin_lock_irqsave(&glink->idr_lock, flags);
699 channel = idr_find(&glink->rcids, cid);
700 spin_unlock_irqrestore(&glink->idr_lock, flags);
701 if (!channel) {
702 dev_err(glink->dev, "invalid channel id received\n");
703 return;
704 }
705
706 spin_lock_irqsave(&channel->intent_lock, flags);
707 intent = idr_find(&channel->riids, iid);
708
709 if (!intent) {
710 spin_unlock_irqrestore(&channel->intent_lock, flags);
711 dev_err(glink->dev, "invalid intent id received\n");
712 return;
713 }
714
715 intent->in_use = false;
716
717 if (!reuse) {
718 idr_remove(&channel->riids, intent->id);
719 kfree(intent);
720 }
721 spin_unlock_irqrestore(&channel->intent_lock, flags);
722 }
723
724 /**
725 * qcom_glink_handle_intent_req() - Receive a request for rx_intent
726 * from remote side
727 * @glink: Pointer to the transport interface
728 * @cid: Remote channel ID
729 * @size: size of the intent
730 *
731 * The function searches for the local channel to which the request for
732 * rx_intent has arrived and allocates and notifies the remote back
733 */
qcom_glink_handle_intent_req(struct qcom_glink * glink,u32 cid,size_t size)734 static void qcom_glink_handle_intent_req(struct qcom_glink *glink,
735 u32 cid, size_t size)
736 {
737 struct glink_core_rx_intent *intent;
738 struct glink_channel *channel;
739 unsigned long flags;
740
741 spin_lock_irqsave(&glink->idr_lock, flags);
742 channel = idr_find(&glink->rcids, cid);
743 spin_unlock_irqrestore(&glink->idr_lock, flags);
744
745 if (!channel) {
746 pr_err("%s channel not found for cid %d\n", __func__, cid);
747 return;
748 }
749
750 intent = qcom_glink_alloc_intent(glink, channel, size, false);
751 if (intent)
752 qcom_glink_advertise_intent(glink, channel, intent);
753
754 qcom_glink_send_intent_req_ack(glink, channel, !!intent);
755 }
756
qcom_glink_rx_defer(struct qcom_glink * glink,size_t extra)757 static int qcom_glink_rx_defer(struct qcom_glink *glink, size_t extra)
758 {
759 struct glink_defer_cmd *dcmd;
760
761 extra = ALIGN(extra, 8);
762
763 if (qcom_glink_rx_avail(glink) < sizeof(struct glink_msg) + extra) {
764 dev_dbg(glink->dev, "Insufficient data in rx fifo");
765 return -ENXIO;
766 }
767
768 dcmd = kzalloc(sizeof(*dcmd) + extra, GFP_ATOMIC);
769 if (!dcmd)
770 return -ENOMEM;
771
772 INIT_LIST_HEAD(&dcmd->node);
773
774 qcom_glink_rx_peak(glink, &dcmd->msg, 0, sizeof(dcmd->msg) + extra);
775
776 spin_lock(&glink->rx_lock);
777 list_add_tail(&dcmd->node, &glink->rx_queue);
778 spin_unlock(&glink->rx_lock);
779
780 schedule_work(&glink->rx_work);
781 qcom_glink_rx_advance(glink, sizeof(dcmd->msg) + extra);
782
783 return 0;
784 }
785
qcom_glink_rx_data(struct qcom_glink * glink,size_t avail)786 static int qcom_glink_rx_data(struct qcom_glink *glink, size_t avail)
787 {
788 struct glink_core_rx_intent *intent;
789 struct glink_channel *channel;
790 struct {
791 struct glink_msg msg;
792 __le32 chunk_size;
793 __le32 left_size;
794 } __packed hdr;
795 unsigned int chunk_size;
796 unsigned int left_size;
797 unsigned int rcid;
798 unsigned int liid;
799 int ret = 0;
800 unsigned long flags;
801
802 if (avail < sizeof(hdr)) {
803 dev_dbg(glink->dev, "Not enough data in fifo\n");
804 return -EAGAIN;
805 }
806
807 qcom_glink_rx_peak(glink, &hdr, 0, sizeof(hdr));
808 chunk_size = le32_to_cpu(hdr.chunk_size);
809 left_size = le32_to_cpu(hdr.left_size);
810
811 if (avail < sizeof(hdr) + chunk_size) {
812 dev_dbg(glink->dev, "Payload not yet in fifo\n");
813 return -EAGAIN;
814 }
815
816 rcid = le16_to_cpu(hdr.msg.param1);
817 spin_lock_irqsave(&glink->idr_lock, flags);
818 channel = idr_find(&glink->rcids, rcid);
819 spin_unlock_irqrestore(&glink->idr_lock, flags);
820 if (!channel) {
821 dev_dbg(glink->dev, "Data on non-existing channel\n");
822
823 /* Drop the message */
824 goto advance_rx;
825 }
826
827 if (glink->intentless) {
828 /* Might have an ongoing, fragmented, message to append */
829 if (!channel->buf) {
830 intent = kzalloc(sizeof(*intent), GFP_ATOMIC);
831 if (!intent)
832 return -ENOMEM;
833
834 intent->data = kmalloc(chunk_size + left_size,
835 GFP_ATOMIC);
836 if (!intent->data) {
837 kfree(intent);
838 return -ENOMEM;
839 }
840
841 intent->id = 0xbabababa;
842 intent->size = chunk_size + left_size;
843 intent->offset = 0;
844
845 channel->buf = intent;
846 } else {
847 intent = channel->buf;
848 }
849 } else {
850 liid = le32_to_cpu(hdr.msg.param2);
851
852 spin_lock_irqsave(&channel->intent_lock, flags);
853 intent = idr_find(&channel->liids, liid);
854 spin_unlock_irqrestore(&channel->intent_lock, flags);
855
856 if (!intent) {
857 dev_err(glink->dev,
858 "no intent found for channel %s intent %d",
859 channel->name, liid);
860 goto advance_rx;
861 }
862 }
863
864 if (intent->size - intent->offset < chunk_size) {
865 dev_err(glink->dev, "Insufficient space in intent\n");
866
867 /* The packet header lied, drop payload */
868 goto advance_rx;
869 }
870
871 qcom_glink_rx_peak(glink, intent->data + intent->offset,
872 sizeof(hdr), chunk_size);
873 intent->offset += chunk_size;
874
875 /* Handle message when no fragments remain to be received */
876 if (!left_size) {
877 spin_lock(&channel->recv_lock);
878 if (channel->ept.cb) {
879 channel->ept.cb(channel->ept.rpdev,
880 intent->data,
881 intent->offset,
882 channel->ept.priv,
883 RPMSG_ADDR_ANY);
884 }
885 spin_unlock(&channel->recv_lock);
886
887 intent->offset = 0;
888 channel->buf = NULL;
889
890 qcom_glink_rx_done(glink, channel, intent);
891 }
892
893 advance_rx:
894 qcom_glink_rx_advance(glink, ALIGN(sizeof(hdr) + chunk_size, 8));
895
896 return ret;
897 }
898
qcom_glink_handle_intent(struct qcom_glink * glink,unsigned int cid,unsigned int count,size_t avail)899 static void qcom_glink_handle_intent(struct qcom_glink *glink,
900 unsigned int cid,
901 unsigned int count,
902 size_t avail)
903 {
904 struct glink_core_rx_intent *intent;
905 struct glink_channel *channel;
906 struct intent_pair {
907 __le32 size;
908 __le32 iid;
909 };
910
911 struct {
912 struct glink_msg msg;
913 struct intent_pair intents[];
914 } __packed * msg;
915
916 const size_t msglen = struct_size(msg, intents, count);
917 int ret;
918 int i;
919 unsigned long flags;
920
921 if (avail < msglen) {
922 dev_dbg(glink->dev, "Not enough data in fifo\n");
923 return;
924 }
925
926 spin_lock_irqsave(&glink->idr_lock, flags);
927 channel = idr_find(&glink->rcids, cid);
928 spin_unlock_irqrestore(&glink->idr_lock, flags);
929 if (!channel) {
930 dev_err(glink->dev, "intents for non-existing channel\n");
931 return;
932 }
933
934 msg = kmalloc(msglen, GFP_ATOMIC);
935 if (!msg)
936 return;
937
938 qcom_glink_rx_peak(glink, msg, 0, msglen);
939
940 for (i = 0; i < count; ++i) {
941 intent = kzalloc(sizeof(*intent), GFP_ATOMIC);
942 if (!intent)
943 break;
944
945 intent->id = le32_to_cpu(msg->intents[i].iid);
946 intent->size = le32_to_cpu(msg->intents[i].size);
947
948 spin_lock_irqsave(&channel->intent_lock, flags);
949 ret = idr_alloc(&channel->riids, intent,
950 intent->id, intent->id + 1, GFP_ATOMIC);
951 spin_unlock_irqrestore(&channel->intent_lock, flags);
952
953 if (ret < 0)
954 dev_err(glink->dev, "failed to store remote intent\n");
955 }
956
957 kfree(msg);
958 qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
959 }
960
qcom_glink_rx_open_ack(struct qcom_glink * glink,unsigned int lcid)961 static int qcom_glink_rx_open_ack(struct qcom_glink *glink, unsigned int lcid)
962 {
963 struct glink_channel *channel;
964
965 spin_lock(&glink->idr_lock);
966 channel = idr_find(&glink->lcids, lcid);
967 spin_unlock(&glink->idr_lock);
968 if (!channel) {
969 dev_err(glink->dev, "Invalid open ack packet\n");
970 return -EINVAL;
971 }
972
973 complete(&channel->open_ack);
974
975 return 0;
976 }
977
qcom_glink_native_intr(int irq,void * data)978 static irqreturn_t qcom_glink_native_intr(int irq, void *data)
979 {
980 struct qcom_glink *glink = data;
981 struct glink_msg msg;
982 unsigned int param1;
983 unsigned int param2;
984 unsigned int avail;
985 unsigned int cmd;
986 int ret = 0;
987
988 for (;;) {
989 avail = qcom_glink_rx_avail(glink);
990 if (avail < sizeof(msg))
991 break;
992
993 qcom_glink_rx_peak(glink, &msg, 0, sizeof(msg));
994
995 cmd = le16_to_cpu(msg.cmd);
996 param1 = le16_to_cpu(msg.param1);
997 param2 = le32_to_cpu(msg.param2);
998
999 switch (cmd) {
1000 case RPM_CMD_VERSION:
1001 case RPM_CMD_VERSION_ACK:
1002 case RPM_CMD_CLOSE:
1003 case RPM_CMD_CLOSE_ACK:
1004 case RPM_CMD_RX_INTENT_REQ:
1005 ret = qcom_glink_rx_defer(glink, 0);
1006 break;
1007 case RPM_CMD_OPEN_ACK:
1008 ret = qcom_glink_rx_open_ack(glink, param1);
1009 qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
1010 break;
1011 case RPM_CMD_OPEN:
1012 ret = qcom_glink_rx_defer(glink, param2);
1013 break;
1014 case RPM_CMD_TX_DATA:
1015 case RPM_CMD_TX_DATA_CONT:
1016 ret = qcom_glink_rx_data(glink, avail);
1017 break;
1018 case RPM_CMD_READ_NOTIF:
1019 qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
1020
1021 mbox_send_message(glink->mbox_chan, NULL);
1022 mbox_client_txdone(glink->mbox_chan, 0);
1023 break;
1024 case RPM_CMD_INTENT:
1025 qcom_glink_handle_intent(glink, param1, param2, avail);
1026 break;
1027 case RPM_CMD_RX_DONE:
1028 qcom_glink_handle_rx_done(glink, param1, param2, false);
1029 qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
1030 break;
1031 case RPM_CMD_RX_DONE_W_REUSE:
1032 qcom_glink_handle_rx_done(glink, param1, param2, true);
1033 qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
1034 break;
1035 case RPM_CMD_RX_INTENT_REQ_ACK:
1036 qcom_glink_handle_intent_req_ack(glink, param1, param2);
1037 qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
1038 break;
1039 default:
1040 dev_err(glink->dev, "unhandled rx cmd: %d\n", cmd);
1041 ret = -EINVAL;
1042 break;
1043 }
1044
1045 if (ret)
1046 break;
1047 }
1048
1049 return IRQ_HANDLED;
1050 }
1051
1052 /* Locally initiated rpmsg_create_ept */
qcom_glink_create_local(struct qcom_glink * glink,const char * name)1053 static struct glink_channel *qcom_glink_create_local(struct qcom_glink *glink,
1054 const char *name)
1055 {
1056 struct glink_channel *channel;
1057 int ret;
1058 unsigned long flags;
1059
1060 channel = qcom_glink_alloc_channel(glink, name);
1061 if (IS_ERR(channel))
1062 return ERR_CAST(channel);
1063
1064 ret = qcom_glink_send_open_req(glink, channel);
1065 if (ret)
1066 goto release_channel;
1067
1068 ret = wait_for_completion_timeout(&channel->open_ack, 5 * HZ);
1069 if (!ret)
1070 goto err_timeout;
1071
1072 ret = wait_for_completion_timeout(&channel->open_req, 5 * HZ);
1073 if (!ret)
1074 goto err_timeout;
1075
1076 qcom_glink_send_open_ack(glink, channel);
1077
1078 return channel;
1079
1080 err_timeout:
1081 /* qcom_glink_send_open_req() did register the channel in lcids*/
1082 spin_lock_irqsave(&glink->idr_lock, flags);
1083 idr_remove(&glink->lcids, channel->lcid);
1084 spin_unlock_irqrestore(&glink->idr_lock, flags);
1085
1086 release_channel:
1087 /* Release qcom_glink_send_open_req() reference */
1088 kref_put(&channel->refcount, qcom_glink_channel_release);
1089 /* Release qcom_glink_alloc_channel() reference */
1090 kref_put(&channel->refcount, qcom_glink_channel_release);
1091
1092 return ERR_PTR(-ETIMEDOUT);
1093 }
1094
1095 /* Remote initiated rpmsg_create_ept */
qcom_glink_create_remote(struct qcom_glink * glink,struct glink_channel * channel)1096 static int qcom_glink_create_remote(struct qcom_glink *glink,
1097 struct glink_channel *channel)
1098 {
1099 int ret;
1100
1101 qcom_glink_send_open_ack(glink, channel);
1102
1103 ret = qcom_glink_send_open_req(glink, channel);
1104 if (ret)
1105 goto close_link;
1106
1107 ret = wait_for_completion_timeout(&channel->open_ack, 5 * HZ);
1108 if (!ret) {
1109 ret = -ETIMEDOUT;
1110 goto close_link;
1111 }
1112
1113 return 0;
1114
1115 close_link:
1116 /*
1117 * Send a close request to "undo" our open-ack. The close-ack will
1118 * release qcom_glink_send_open_req() reference and the last reference
1119 * will be relesed after receiving remote_close or transport unregister
1120 * by calling qcom_glink_native_remove().
1121 */
1122 qcom_glink_send_close_req(glink, channel);
1123
1124 return ret;
1125 }
1126
qcom_glink_create_ept(struct rpmsg_device * rpdev,rpmsg_rx_cb_t cb,void * priv,struct rpmsg_channel_info chinfo)1127 static struct rpmsg_endpoint *qcom_glink_create_ept(struct rpmsg_device *rpdev,
1128 rpmsg_rx_cb_t cb,
1129 void *priv,
1130 struct rpmsg_channel_info
1131 chinfo)
1132 {
1133 struct glink_channel *parent = to_glink_channel(rpdev->ept);
1134 struct glink_channel *channel;
1135 struct qcom_glink *glink = parent->glink;
1136 struct rpmsg_endpoint *ept;
1137 const char *name = chinfo.name;
1138 int cid;
1139 int ret;
1140 unsigned long flags;
1141
1142 spin_lock_irqsave(&glink->idr_lock, flags);
1143 idr_for_each_entry(&glink->rcids, channel, cid) {
1144 if (!strcmp(channel->name, name))
1145 break;
1146 }
1147 spin_unlock_irqrestore(&glink->idr_lock, flags);
1148
1149 if (!channel) {
1150 channel = qcom_glink_create_local(glink, name);
1151 if (IS_ERR(channel))
1152 return NULL;
1153 } else {
1154 ret = qcom_glink_create_remote(glink, channel);
1155 if (ret)
1156 return NULL;
1157 }
1158
1159 ept = &channel->ept;
1160 ept->rpdev = rpdev;
1161 ept->cb = cb;
1162 ept->priv = priv;
1163 ept->ops = &glink_endpoint_ops;
1164
1165 return ept;
1166 }
1167
qcom_glink_announce_create(struct rpmsg_device * rpdev)1168 static int qcom_glink_announce_create(struct rpmsg_device *rpdev)
1169 {
1170 struct glink_channel *channel = to_glink_channel(rpdev->ept);
1171 struct device_node *np = rpdev->dev.of_node;
1172 struct qcom_glink *glink = channel->glink;
1173 struct glink_core_rx_intent *intent;
1174 const struct property *prop = NULL;
1175 __be32 defaults[] = { cpu_to_be32(SZ_1K), cpu_to_be32(5) };
1176 int num_intents;
1177 int num_groups = 1;
1178 __be32 *val = defaults;
1179 int size;
1180
1181 if (glink->intentless)
1182 return 0;
1183
1184 prop = of_find_property(np, "qcom,intents", NULL);
1185 if (prop) {
1186 val = prop->value;
1187 num_groups = prop->length / sizeof(u32) / 2;
1188 }
1189
1190 /* Channel is now open, advertise base set of intents */
1191 while (num_groups--) {
1192 size = be32_to_cpup(val++);
1193 num_intents = be32_to_cpup(val++);
1194 while (num_intents--) {
1195 intent = qcom_glink_alloc_intent(glink, channel, size,
1196 true);
1197 if (!intent)
1198 break;
1199
1200 qcom_glink_advertise_intent(glink, channel, intent);
1201 }
1202 }
1203 return 0;
1204 }
1205
qcom_glink_destroy_ept(struct rpmsg_endpoint * ept)1206 static void qcom_glink_destroy_ept(struct rpmsg_endpoint *ept)
1207 {
1208 struct glink_channel *channel = to_glink_channel(ept);
1209 struct qcom_glink *glink = channel->glink;
1210 unsigned long flags;
1211
1212 spin_lock_irqsave(&channel->recv_lock, flags);
1213 channel->ept.cb = NULL;
1214 spin_unlock_irqrestore(&channel->recv_lock, flags);
1215
1216 /* Decouple the potential rpdev from the channel */
1217 channel->rpdev = NULL;
1218
1219 qcom_glink_send_close_req(glink, channel);
1220 }
1221
qcom_glink_request_intent(struct qcom_glink * glink,struct glink_channel * channel,size_t size)1222 static int qcom_glink_request_intent(struct qcom_glink *glink,
1223 struct glink_channel *channel,
1224 size_t size)
1225 {
1226 struct {
1227 u16 id;
1228 u16 cid;
1229 u32 size;
1230 } __packed cmd;
1231
1232 int ret;
1233
1234 mutex_lock(&channel->intent_req_lock);
1235
1236 reinit_completion(&channel->intent_req_comp);
1237
1238 cmd.id = RPM_CMD_RX_INTENT_REQ;
1239 cmd.cid = channel->lcid;
1240 cmd.size = size;
1241
1242 ret = qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
1243 if (ret)
1244 goto unlock;
1245
1246 ret = wait_for_completion_timeout(&channel->intent_req_comp, 10 * HZ);
1247 if (!ret) {
1248 dev_err(glink->dev, "intent request timed out\n");
1249 ret = -ETIMEDOUT;
1250 } else {
1251 ret = channel->intent_req_result ? 0 : -ECANCELED;
1252 }
1253
1254 unlock:
1255 mutex_unlock(&channel->intent_req_lock);
1256 return ret;
1257 }
1258
__qcom_glink_send(struct glink_channel * channel,void * data,int len,bool wait)1259 static int __qcom_glink_send(struct glink_channel *channel,
1260 void *data, int len, bool wait)
1261 {
1262 struct qcom_glink *glink = channel->glink;
1263 struct glink_core_rx_intent *intent = NULL;
1264 struct glink_core_rx_intent *tmp;
1265 int iid = 0;
1266 struct {
1267 struct glink_msg msg;
1268 __le32 chunk_size;
1269 __le32 left_size;
1270 } __packed req;
1271 int ret;
1272 unsigned long flags;
1273
1274 if (!glink->intentless) {
1275 while (!intent) {
1276 spin_lock_irqsave(&channel->intent_lock, flags);
1277 idr_for_each_entry(&channel->riids, tmp, iid) {
1278 if (tmp->size >= len && !tmp->in_use) {
1279 if (!intent)
1280 intent = tmp;
1281 else if (intent->size > tmp->size)
1282 intent = tmp;
1283 if (intent->size == len)
1284 break;
1285 }
1286 }
1287 if (intent)
1288 intent->in_use = true;
1289 spin_unlock_irqrestore(&channel->intent_lock, flags);
1290
1291 /* We found an available intent */
1292 if (intent)
1293 break;
1294
1295 if (!wait)
1296 return -EBUSY;
1297
1298 ret = qcom_glink_request_intent(glink, channel, len);
1299 if (ret < 0)
1300 return ret;
1301 }
1302
1303 iid = intent->id;
1304 }
1305
1306 req.msg.cmd = cpu_to_le16(RPM_CMD_TX_DATA);
1307 req.msg.param1 = cpu_to_le16(channel->lcid);
1308 req.msg.param2 = cpu_to_le32(iid);
1309 req.chunk_size = cpu_to_le32(len);
1310 req.left_size = cpu_to_le32(0);
1311
1312 ret = qcom_glink_tx(glink, &req, sizeof(req), data, len, wait);
1313
1314 /* Mark intent available if we failed */
1315 if (ret && intent)
1316 intent->in_use = false;
1317
1318 return ret;
1319 }
1320
qcom_glink_send(struct rpmsg_endpoint * ept,void * data,int len)1321 static int qcom_glink_send(struct rpmsg_endpoint *ept, void *data, int len)
1322 {
1323 struct glink_channel *channel = to_glink_channel(ept);
1324
1325 return __qcom_glink_send(channel, data, len, true);
1326 }
1327
qcom_glink_trysend(struct rpmsg_endpoint * ept,void * data,int len)1328 static int qcom_glink_trysend(struct rpmsg_endpoint *ept, void *data, int len)
1329 {
1330 struct glink_channel *channel = to_glink_channel(ept);
1331
1332 return __qcom_glink_send(channel, data, len, false);
1333 }
1334
1335 /*
1336 * Finds the device_node for the glink child interested in this channel.
1337 */
qcom_glink_match_channel(struct device_node * node,const char * channel)1338 static struct device_node *qcom_glink_match_channel(struct device_node *node,
1339 const char *channel)
1340 {
1341 struct device_node *child;
1342 const char *name;
1343 const char *key;
1344 int ret;
1345
1346 for_each_available_child_of_node(node, child) {
1347 key = "qcom,glink-channels";
1348 ret = of_property_read_string(child, key, &name);
1349 if (ret)
1350 continue;
1351
1352 if (strcmp(name, channel) == 0)
1353 return child;
1354 }
1355
1356 return NULL;
1357 }
1358
1359 static const struct rpmsg_device_ops glink_device_ops = {
1360 .create_ept = qcom_glink_create_ept,
1361 .announce_create = qcom_glink_announce_create,
1362 };
1363
1364 static const struct rpmsg_endpoint_ops glink_endpoint_ops = {
1365 .destroy_ept = qcom_glink_destroy_ept,
1366 .send = qcom_glink_send,
1367 .trysend = qcom_glink_trysend,
1368 };
1369
qcom_glink_rpdev_release(struct device * dev)1370 static void qcom_glink_rpdev_release(struct device *dev)
1371 {
1372 struct rpmsg_device *rpdev = to_rpmsg_device(dev);
1373 struct glink_channel *channel = to_glink_channel(rpdev->ept);
1374
1375 channel->rpdev = NULL;
1376 kfree(rpdev);
1377 }
1378
qcom_glink_rx_open(struct qcom_glink * glink,unsigned int rcid,char * name)1379 static int qcom_glink_rx_open(struct qcom_glink *glink, unsigned int rcid,
1380 char *name)
1381 {
1382 struct glink_channel *channel;
1383 struct rpmsg_device *rpdev;
1384 bool create_device = false;
1385 struct device_node *node;
1386 int lcid;
1387 int ret;
1388 unsigned long flags;
1389
1390 spin_lock_irqsave(&glink->idr_lock, flags);
1391 idr_for_each_entry(&glink->lcids, channel, lcid) {
1392 if (!strcmp(channel->name, name))
1393 break;
1394 }
1395 spin_unlock_irqrestore(&glink->idr_lock, flags);
1396
1397 if (!channel) {
1398 channel = qcom_glink_alloc_channel(glink, name);
1399 if (IS_ERR(channel))
1400 return PTR_ERR(channel);
1401
1402 /* The opening dance was initiated by the remote */
1403 create_device = true;
1404 }
1405
1406 spin_lock_irqsave(&glink->idr_lock, flags);
1407 ret = idr_alloc(&glink->rcids, channel, rcid, rcid + 1, GFP_ATOMIC);
1408 if (ret < 0) {
1409 dev_err(glink->dev, "Unable to insert channel into rcid list\n");
1410 spin_unlock_irqrestore(&glink->idr_lock, flags);
1411 goto free_channel;
1412 }
1413 channel->rcid = ret;
1414 spin_unlock_irqrestore(&glink->idr_lock, flags);
1415
1416 complete(&channel->open_req);
1417
1418 if (create_device) {
1419 rpdev = kzalloc(sizeof(*rpdev), GFP_KERNEL);
1420 if (!rpdev) {
1421 ret = -ENOMEM;
1422 goto rcid_remove;
1423 }
1424
1425 rpdev->ept = &channel->ept;
1426 strncpy(rpdev->id.name, name, RPMSG_NAME_SIZE);
1427 rpdev->src = RPMSG_ADDR_ANY;
1428 rpdev->dst = RPMSG_ADDR_ANY;
1429 rpdev->ops = &glink_device_ops;
1430
1431 node = qcom_glink_match_channel(glink->dev->of_node, name);
1432 rpdev->dev.of_node = node;
1433 rpdev->dev.parent = glink->dev;
1434 rpdev->dev.release = qcom_glink_rpdev_release;
1435
1436 ret = rpmsg_register_device(rpdev);
1437 if (ret)
1438 goto rcid_remove;
1439
1440 channel->rpdev = rpdev;
1441 }
1442
1443 return 0;
1444
1445 rcid_remove:
1446 spin_lock_irqsave(&glink->idr_lock, flags);
1447 idr_remove(&glink->rcids, channel->rcid);
1448 channel->rcid = 0;
1449 spin_unlock_irqrestore(&glink->idr_lock, flags);
1450 free_channel:
1451 /* Release the reference, iff we took it */
1452 if (create_device)
1453 kref_put(&channel->refcount, qcom_glink_channel_release);
1454
1455 return ret;
1456 }
1457
qcom_glink_rx_close(struct qcom_glink * glink,unsigned int rcid)1458 static void qcom_glink_rx_close(struct qcom_glink *glink, unsigned int rcid)
1459 {
1460 struct rpmsg_channel_info chinfo;
1461 struct glink_channel *channel;
1462 unsigned long flags;
1463
1464 spin_lock_irqsave(&glink->idr_lock, flags);
1465 channel = idr_find(&glink->rcids, rcid);
1466 spin_unlock_irqrestore(&glink->idr_lock, flags);
1467 if (WARN(!channel, "close request on unknown channel\n"))
1468 return;
1469
1470 /* cancel pending rx_done work */
1471 cancel_work_sync(&channel->intent_work);
1472
1473 if (channel->rpdev) {
1474 strncpy(chinfo.name, channel->name, sizeof(chinfo.name));
1475 chinfo.src = RPMSG_ADDR_ANY;
1476 chinfo.dst = RPMSG_ADDR_ANY;
1477
1478 rpmsg_unregister_device(glink->dev, &chinfo);
1479 }
1480
1481 qcom_glink_send_close_ack(glink, channel->rcid);
1482
1483 spin_lock_irqsave(&glink->idr_lock, flags);
1484 idr_remove(&glink->rcids, channel->rcid);
1485 channel->rcid = 0;
1486 spin_unlock_irqrestore(&glink->idr_lock, flags);
1487
1488 kref_put(&channel->refcount, qcom_glink_channel_release);
1489 }
1490
qcom_glink_rx_close_ack(struct qcom_glink * glink,unsigned int lcid)1491 static void qcom_glink_rx_close_ack(struct qcom_glink *glink, unsigned int lcid)
1492 {
1493 struct glink_channel *channel;
1494 unsigned long flags;
1495
1496 spin_lock_irqsave(&glink->idr_lock, flags);
1497 channel = idr_find(&glink->lcids, lcid);
1498 if (WARN(!channel, "close ack on unknown channel\n")) {
1499 spin_unlock_irqrestore(&glink->idr_lock, flags);
1500 return;
1501 }
1502
1503 idr_remove(&glink->lcids, channel->lcid);
1504 channel->lcid = 0;
1505 spin_unlock_irqrestore(&glink->idr_lock, flags);
1506
1507 kref_put(&channel->refcount, qcom_glink_channel_release);
1508 }
1509
qcom_glink_work(struct work_struct * work)1510 static void qcom_glink_work(struct work_struct *work)
1511 {
1512 struct qcom_glink *glink = container_of(work, struct qcom_glink,
1513 rx_work);
1514 struct glink_defer_cmd *dcmd;
1515 struct glink_msg *msg;
1516 unsigned long flags;
1517 unsigned int param1;
1518 unsigned int param2;
1519 unsigned int cmd;
1520
1521 for (;;) {
1522 spin_lock_irqsave(&glink->rx_lock, flags);
1523 if (list_empty(&glink->rx_queue)) {
1524 spin_unlock_irqrestore(&glink->rx_lock, flags);
1525 break;
1526 }
1527 dcmd = list_first_entry(&glink->rx_queue,
1528 struct glink_defer_cmd, node);
1529 list_del(&dcmd->node);
1530 spin_unlock_irqrestore(&glink->rx_lock, flags);
1531
1532 msg = &dcmd->msg;
1533 cmd = le16_to_cpu(msg->cmd);
1534 param1 = le16_to_cpu(msg->param1);
1535 param2 = le32_to_cpu(msg->param2);
1536
1537 switch (cmd) {
1538 case RPM_CMD_VERSION:
1539 qcom_glink_receive_version(glink, param1, param2);
1540 break;
1541 case RPM_CMD_VERSION_ACK:
1542 qcom_glink_receive_version_ack(glink, param1, param2);
1543 break;
1544 case RPM_CMD_OPEN:
1545 qcom_glink_rx_open(glink, param1, msg->data);
1546 break;
1547 case RPM_CMD_CLOSE:
1548 qcom_glink_rx_close(glink, param1);
1549 break;
1550 case RPM_CMD_CLOSE_ACK:
1551 qcom_glink_rx_close_ack(glink, param1);
1552 break;
1553 case RPM_CMD_RX_INTENT_REQ:
1554 qcom_glink_handle_intent_req(glink, param1, param2);
1555 break;
1556 default:
1557 WARN(1, "Unknown defer object %d\n", cmd);
1558 break;
1559 }
1560
1561 kfree(dcmd);
1562 }
1563 }
1564
qcom_glink_cancel_rx_work(struct qcom_glink * glink)1565 static void qcom_glink_cancel_rx_work(struct qcom_glink *glink)
1566 {
1567 struct glink_defer_cmd *dcmd;
1568 struct glink_defer_cmd *tmp;
1569
1570 /* cancel any pending deferred rx_work */
1571 cancel_work_sync(&glink->rx_work);
1572
1573 list_for_each_entry_safe(dcmd, tmp, &glink->rx_queue, node)
1574 kfree(dcmd);
1575 }
1576
qcom_glink_native_probe(struct device * dev,unsigned long features,struct qcom_glink_pipe * rx,struct qcom_glink_pipe * tx,bool intentless)1577 struct qcom_glink *qcom_glink_native_probe(struct device *dev,
1578 unsigned long features,
1579 struct qcom_glink_pipe *rx,
1580 struct qcom_glink_pipe *tx,
1581 bool intentless)
1582 {
1583 int irq;
1584 int ret;
1585 struct qcom_glink *glink;
1586
1587 glink = devm_kzalloc(dev, sizeof(*glink), GFP_KERNEL);
1588 if (!glink)
1589 return ERR_PTR(-ENOMEM);
1590
1591 glink->dev = dev;
1592 glink->tx_pipe = tx;
1593 glink->rx_pipe = rx;
1594
1595 glink->features = features;
1596 glink->intentless = intentless;
1597
1598 spin_lock_init(&glink->tx_lock);
1599 spin_lock_init(&glink->rx_lock);
1600 INIT_LIST_HEAD(&glink->rx_queue);
1601 INIT_WORK(&glink->rx_work, qcom_glink_work);
1602
1603 spin_lock_init(&glink->idr_lock);
1604 idr_init(&glink->lcids);
1605 idr_init(&glink->rcids);
1606
1607 ret = of_property_read_string(dev->of_node, "label", &glink->name);
1608 if (ret < 0)
1609 glink->name = dev->of_node->name;
1610
1611 glink->mbox_client.dev = dev;
1612 glink->mbox_client.knows_txdone = true;
1613 glink->mbox_chan = mbox_request_channel(&glink->mbox_client, 0);
1614 if (IS_ERR(glink->mbox_chan)) {
1615 if (PTR_ERR(glink->mbox_chan) != -EPROBE_DEFER)
1616 dev_err(dev, "failed to acquire IPC channel\n");
1617 return ERR_CAST(glink->mbox_chan);
1618 }
1619
1620 irq = of_irq_get(dev->of_node, 0);
1621 ret = devm_request_irq(dev, irq,
1622 qcom_glink_native_intr,
1623 IRQF_NO_SUSPEND | IRQF_SHARED,
1624 "glink-native", glink);
1625 if (ret) {
1626 dev_err(dev, "failed to request IRQ\n");
1627 return ERR_PTR(ret);
1628 }
1629
1630 glink->irq = irq;
1631
1632 ret = qcom_glink_send_version(glink);
1633 if (ret)
1634 return ERR_PTR(ret);
1635
1636 return glink;
1637 }
1638 EXPORT_SYMBOL_GPL(qcom_glink_native_probe);
1639
qcom_glink_remove_device(struct device * dev,void * data)1640 static int qcom_glink_remove_device(struct device *dev, void *data)
1641 {
1642 device_unregister(dev);
1643
1644 return 0;
1645 }
1646
qcom_glink_native_remove(struct qcom_glink * glink)1647 void qcom_glink_native_remove(struct qcom_glink *glink)
1648 {
1649 struct glink_channel *channel;
1650 int cid;
1651 int ret;
1652
1653 disable_irq(glink->irq);
1654 qcom_glink_cancel_rx_work(glink);
1655
1656 ret = device_for_each_child(glink->dev, NULL, qcom_glink_remove_device);
1657 if (ret)
1658 dev_warn(glink->dev, "Can't remove GLINK devices: %d\n", ret);
1659
1660 /* Release any defunct local channels, waiting for close-ack */
1661 idr_for_each_entry(&glink->lcids, channel, cid)
1662 kref_put(&channel->refcount, qcom_glink_channel_release);
1663
1664 /* Release any defunct local channels, waiting for close-req */
1665 idr_for_each_entry(&glink->rcids, channel, cid)
1666 kref_put(&channel->refcount, qcom_glink_channel_release);
1667
1668 idr_destroy(&glink->lcids);
1669 idr_destroy(&glink->rcids);
1670 mbox_free_channel(glink->mbox_chan);
1671 }
1672 EXPORT_SYMBOL_GPL(qcom_glink_native_remove);
1673
qcom_glink_native_unregister(struct qcom_glink * glink)1674 void qcom_glink_native_unregister(struct qcom_glink *glink)
1675 {
1676 device_unregister(glink->dev);
1677 }
1678 EXPORT_SYMBOL_GPL(qcom_glink_native_unregister);
1679
1680 MODULE_DESCRIPTION("Qualcomm GLINK driver");
1681 MODULE_LICENSE("GPL v2");
1682