]>
Commit | Line | Data |
---|---|---|
53e2822e BA |
1 | /* |
2 | * Copyright (c) 2015, Sony Mobile Communications AB. | |
3 | * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 and | |
7 | * only version 2 as published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | */ | |
14 | ||
15 | #include <linux/interrupt.h> | |
16 | #include <linux/io.h> | |
17 | #include <linux/mfd/syscon.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/of_irq.h> | |
20 | #include <linux/of_platform.h> | |
21 | #include <linux/platform_device.h> | |
22 | #include <linux/regmap.h> | |
23 | #include <linux/sched.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/soc/qcom/smem.h> | |
26 | #include <linux/wait.h> | |
27 | #include <linux/rpmsg.h> | |
8fc94723 | 28 | #include <linux/rpmsg/qcom_smd.h> |
53e2822e BA |
29 | |
30 | #include "rpmsg_internal.h" | |
31 | ||
32 | /* | |
33 | * The Qualcomm Shared Memory communication solution provides point-to-point | |
34 | * channels for clients to send and receive streaming or packet based data. | |
35 | * | |
36 | * Each channel consists of a control item (channel info) and a ring buffer | |
37 | * pair. The channel info carry information related to channel state, flow | |
38 | * control and the offsets within the ring buffer. | |
39 | * | |
40 | * All allocated channels are listed in an allocation table, identifying the | |
41 | * pair of items by name, type and remote processor. | |
42 | * | |
43 | * Upon creating a new channel the remote processor allocates channel info and | |
44 | * ring buffer items from the smem heap and populate the allocation table. An | |
45 | * interrupt is sent to the other end of the channel and a scan for new | |
46 | * channels should be done. A channel never goes away, it will only change | |
47 | * state. | |
48 | * | |
49 | * The remote processor signals it intent for bring up the communication | |
50 | * channel by setting the state of its end of the channel to "opening" and | |
51 | * sends out an interrupt. We detect this change and register a smd device to | |
52 | * consume the channel. Upon finding a consumer we finish the handshake and the | |
53 | * channel is up. | |
54 | * | |
55 | * Upon closing a channel, the remote processor will update the state of its | |
56 | * end of the channel and signal us, we will then unregister any attached | |
57 | * device and close our end of the channel. | |
58 | * | |
59 | * Devices attached to a channel can use the qcom_smd_send function to push | |
60 | * data to the channel, this is done by copying the data into the tx ring | |
61 | * buffer, updating the pointers in the channel info and signaling the remote | |
62 | * processor. | |
63 | * | |
64 | * The remote processor does the equivalent when it transfer data and upon | |
65 | * receiving the interrupt we check the channel info for new data and delivers | |
66 | * this to the attached device. If the device is not ready to receive the data | |
67 | * we leave it in the ring buffer for now. | |
68 | */ | |
69 | ||
70 | struct smd_channel_info; | |
71 | struct smd_channel_info_pair; | |
72 | struct smd_channel_info_word; | |
73 | struct smd_channel_info_word_pair; | |
74 | ||
75 | static const struct rpmsg_endpoint_ops qcom_smd_endpoint_ops; | |
76 | ||
77 | #define SMD_ALLOC_TBL_COUNT 2 | |
78 | #define SMD_ALLOC_TBL_SIZE 64 | |
79 | ||
80 | /* | |
81 | * This lists the various smem heap items relevant for the allocation table and | |
82 | * smd channel entries. | |
83 | */ | |
84 | static const struct { | |
85 | unsigned alloc_tbl_id; | |
86 | unsigned info_base_id; | |
87 | unsigned fifo_base_id; | |
88 | } smem_items[SMD_ALLOC_TBL_COUNT] = { | |
89 | { | |
90 | .alloc_tbl_id = 13, | |
91 | .info_base_id = 14, | |
92 | .fifo_base_id = 338 | |
93 | }, | |
94 | { | |
95 | .alloc_tbl_id = 266, | |
96 | .info_base_id = 138, | |
97 | .fifo_base_id = 202, | |
98 | }, | |
99 | }; | |
100 | ||
101 | /** | |
102 | * struct qcom_smd_edge - representing a remote processor | |
103 | * @of_node: of_node handle for information related to this edge | |
104 | * @edge_id: identifier of this edge | |
105 | * @remote_pid: identifier of remote processor | |
106 | * @irq: interrupt for signals on this edge | |
107 | * @ipc_regmap: regmap handle holding the outgoing ipc register | |
108 | * @ipc_offset: offset within @ipc_regmap of the register for ipc | |
109 | * @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap | |
110 | * @channels: list of all channels detected on this edge | |
111 | * @channels_lock: guard for modifications of @channels | |
112 | * @allocated: array of bitmaps representing already allocated channels | |
113 | * @smem_available: last available amount of smem triggering a channel scan | |
114 | * @scan_work: work item for discovering new channels | |
115 | * @state_work: work item for edge state changes | |
116 | */ | |
117 | struct qcom_smd_edge { | |
118 | struct device dev; | |
119 | ||
120 | struct device_node *of_node; | |
121 | unsigned edge_id; | |
122 | unsigned remote_pid; | |
123 | ||
124 | int irq; | |
125 | ||
126 | struct regmap *ipc_regmap; | |
127 | int ipc_offset; | |
128 | int ipc_bit; | |
129 | ||
130 | struct list_head channels; | |
131 | spinlock_t channels_lock; | |
132 | ||
133 | DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE); | |
134 | ||
135 | unsigned smem_available; | |
136 | ||
137 | wait_queue_head_t new_channel_event; | |
138 | ||
139 | struct work_struct scan_work; | |
140 | struct work_struct state_work; | |
141 | }; | |
142 | ||
143 | /* | |
144 | * SMD channel states. | |
145 | */ | |
146 | enum smd_channel_state { | |
147 | SMD_CHANNEL_CLOSED, | |
148 | SMD_CHANNEL_OPENING, | |
149 | SMD_CHANNEL_OPENED, | |
150 | SMD_CHANNEL_FLUSHING, | |
151 | SMD_CHANNEL_CLOSING, | |
152 | SMD_CHANNEL_RESET, | |
153 | SMD_CHANNEL_RESET_OPENING | |
154 | }; | |
155 | ||
156 | struct qcom_smd_device { | |
157 | struct rpmsg_device rpdev; | |
158 | ||
159 | struct qcom_smd_edge *edge; | |
160 | }; | |
161 | ||
162 | struct qcom_smd_endpoint { | |
163 | struct rpmsg_endpoint ept; | |
164 | ||
165 | struct qcom_smd_channel *qsch; | |
166 | }; | |
167 | ||
168 | #define to_smd_device(_rpdev) container_of(_rpdev, struct qcom_smd_device, rpdev) | |
169 | #define to_smd_edge(d) container_of(d, struct qcom_smd_edge, dev) | |
170 | #define to_smd_endpoint(ept) container_of(ept, struct qcom_smd_endpoint, ept) | |
171 | ||
172 | /** | |
173 | * struct qcom_smd_channel - smd channel struct | |
174 | * @edge: qcom_smd_edge this channel is living on | |
175 | * @qsdev: reference to a associated smd client device | |
176 | * @name: name of the channel | |
177 | * @state: local state of the channel | |
178 | * @remote_state: remote state of the channel | |
179 | * @info: byte aligned outgoing/incoming channel info | |
180 | * @info_word: word aligned outgoing/incoming channel info | |
181 | * @tx_lock: lock to make writes to the channel mutually exclusive | |
182 | * @fblockread_event: wakeup event tied to tx fBLOCKREADINTR | |
183 | * @tx_fifo: pointer to the outgoing ring buffer | |
184 | * @rx_fifo: pointer to the incoming ring buffer | |
185 | * @fifo_size: size of each ring buffer | |
186 | * @bounce_buffer: bounce buffer for reading wrapped packets | |
187 | * @cb: callback function registered for this channel | |
188 | * @recv_lock: guard for rx info modifications and cb pointer | |
189 | * @pkt_size: size of the currently handled packet | |
190 | * @list: lite entry for @channels in qcom_smd_edge | |
191 | */ | |
192 | struct qcom_smd_channel { | |
193 | struct qcom_smd_edge *edge; | |
194 | ||
195 | struct qcom_smd_endpoint *qsept; | |
196 | bool registered; | |
197 | ||
198 | char *name; | |
199 | enum smd_channel_state state; | |
200 | enum smd_channel_state remote_state; | |
201 | ||
202 | struct smd_channel_info_pair *info; | |
203 | struct smd_channel_info_word_pair *info_word; | |
204 | ||
205 | struct mutex tx_lock; | |
206 | wait_queue_head_t fblockread_event; | |
207 | ||
208 | void *tx_fifo; | |
209 | void *rx_fifo; | |
210 | int fifo_size; | |
211 | ||
212 | void *bounce_buffer; | |
213 | ||
214 | spinlock_t recv_lock; | |
215 | ||
216 | int pkt_size; | |
217 | ||
218 | void *drvdata; | |
219 | ||
220 | struct list_head list; | |
221 | }; | |
222 | ||
223 | /* | |
224 | * Format of the smd_info smem items, for byte aligned channels. | |
225 | */ | |
226 | struct smd_channel_info { | |
227 | __le32 state; | |
228 | u8 fDSR; | |
229 | u8 fCTS; | |
230 | u8 fCD; | |
231 | u8 fRI; | |
232 | u8 fHEAD; | |
233 | u8 fTAIL; | |
234 | u8 fSTATE; | |
235 | u8 fBLOCKREADINTR; | |
236 | __le32 tail; | |
237 | __le32 head; | |
238 | }; | |
239 | ||
240 | struct smd_channel_info_pair { | |
241 | struct smd_channel_info tx; | |
242 | struct smd_channel_info rx; | |
243 | }; | |
244 | ||
245 | /* | |
246 | * Format of the smd_info smem items, for word aligned channels. | |
247 | */ | |
248 | struct smd_channel_info_word { | |
249 | __le32 state; | |
250 | __le32 fDSR; | |
251 | __le32 fCTS; | |
252 | __le32 fCD; | |
253 | __le32 fRI; | |
254 | __le32 fHEAD; | |
255 | __le32 fTAIL; | |
256 | __le32 fSTATE; | |
257 | __le32 fBLOCKREADINTR; | |
258 | __le32 tail; | |
259 | __le32 head; | |
260 | }; | |
261 | ||
262 | struct smd_channel_info_word_pair { | |
263 | struct smd_channel_info_word tx; | |
264 | struct smd_channel_info_word rx; | |
265 | }; | |
266 | ||
267 | #define GET_RX_CHANNEL_FLAG(channel, param) \ | |
268 | ({ \ | |
269 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
270 | channel->info_word ? \ | |
271 | le32_to_cpu(channel->info_word->rx.param) : \ | |
272 | channel->info->rx.param; \ | |
273 | }) | |
274 | ||
275 | #define GET_RX_CHANNEL_INFO(channel, param) \ | |
276 | ({ \ | |
277 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
278 | le32_to_cpu(channel->info_word ? \ | |
279 | channel->info_word->rx.param : \ | |
280 | channel->info->rx.param); \ | |
281 | }) | |
282 | ||
283 | #define SET_RX_CHANNEL_FLAG(channel, param, value) \ | |
284 | ({ \ | |
285 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
286 | if (channel->info_word) \ | |
287 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
288 | else \ | |
289 | channel->info->rx.param = value; \ | |
290 | }) | |
291 | ||
292 | #define SET_RX_CHANNEL_INFO(channel, param, value) \ | |
293 | ({ \ | |
294 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
295 | if (channel->info_word) \ | |
296 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
297 | else \ | |
298 | channel->info->rx.param = cpu_to_le32(value); \ | |
299 | }) | |
300 | ||
301 | #define GET_TX_CHANNEL_FLAG(channel, param) \ | |
302 | ({ \ | |
303 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
304 | channel->info_word ? \ | |
305 | le32_to_cpu(channel->info_word->tx.param) : \ | |
306 | channel->info->tx.param; \ | |
307 | }) | |
308 | ||
309 | #define GET_TX_CHANNEL_INFO(channel, param) \ | |
310 | ({ \ | |
311 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
312 | le32_to_cpu(channel->info_word ? \ | |
313 | channel->info_word->tx.param : \ | |
314 | channel->info->tx.param); \ | |
315 | }) | |
316 | ||
317 | #define SET_TX_CHANNEL_FLAG(channel, param, value) \ | |
318 | ({ \ | |
319 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
320 | if (channel->info_word) \ | |
321 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
322 | else \ | |
323 | channel->info->tx.param = value; \ | |
324 | }) | |
325 | ||
326 | #define SET_TX_CHANNEL_INFO(channel, param, value) \ | |
327 | ({ \ | |
328 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
329 | if (channel->info_word) \ | |
330 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
331 | else \ | |
332 | channel->info->tx.param = cpu_to_le32(value); \ | |
333 | }) | |
334 | ||
335 | /** | |
336 | * struct qcom_smd_alloc_entry - channel allocation entry | |
337 | * @name: channel name | |
338 | * @cid: channel index | |
339 | * @flags: channel flags and edge id | |
340 | * @ref_count: reference count of the channel | |
341 | */ | |
342 | struct qcom_smd_alloc_entry { | |
343 | u8 name[20]; | |
344 | __le32 cid; | |
345 | __le32 flags; | |
346 | __le32 ref_count; | |
347 | } __packed; | |
348 | ||
349 | #define SMD_CHANNEL_FLAGS_EDGE_MASK 0xff | |
350 | #define SMD_CHANNEL_FLAGS_STREAM BIT(8) | |
351 | #define SMD_CHANNEL_FLAGS_PACKET BIT(9) | |
352 | ||
353 | /* | |
354 | * Each smd packet contains a 20 byte header, with the first 4 being the length | |
355 | * of the packet. | |
356 | */ | |
357 | #define SMD_PACKET_HEADER_LEN 20 | |
358 | ||
359 | /* | |
360 | * Signal the remote processor associated with 'channel'. | |
361 | */ | |
362 | static void qcom_smd_signal_channel(struct qcom_smd_channel *channel) | |
363 | { | |
364 | struct qcom_smd_edge *edge = channel->edge; | |
365 | ||
366 | regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit)); | |
367 | } | |
368 | ||
369 | /* | |
370 | * Initialize the tx channel info | |
371 | */ | |
372 | static void qcom_smd_channel_reset(struct qcom_smd_channel *channel) | |
373 | { | |
374 | SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); | |
375 | SET_TX_CHANNEL_FLAG(channel, fDSR, 0); | |
376 | SET_TX_CHANNEL_FLAG(channel, fCTS, 0); | |
377 | SET_TX_CHANNEL_FLAG(channel, fCD, 0); | |
378 | SET_TX_CHANNEL_FLAG(channel, fRI, 0); | |
379 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 0); | |
380 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); | |
381 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); | |
382 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); | |
383 | SET_TX_CHANNEL_INFO(channel, head, 0); | |
384 | SET_RX_CHANNEL_INFO(channel, tail, 0); | |
385 | ||
386 | qcom_smd_signal_channel(channel); | |
387 | ||
388 | channel->state = SMD_CHANNEL_CLOSED; | |
389 | channel->pkt_size = 0; | |
390 | } | |
391 | ||
392 | /* | |
393 | * Set the callback for a channel, with appropriate locking | |
394 | */ | |
395 | static void qcom_smd_channel_set_callback(struct qcom_smd_channel *channel, | |
396 | rpmsg_rx_cb_t cb) | |
397 | { | |
398 | struct rpmsg_endpoint *ept = &channel->qsept->ept; | |
399 | unsigned long flags; | |
400 | ||
401 | spin_lock_irqsave(&channel->recv_lock, flags); | |
402 | ept->cb = cb; | |
403 | spin_unlock_irqrestore(&channel->recv_lock, flags); | |
404 | }; | |
405 | ||
406 | /* | |
407 | * Calculate the amount of data available in the rx fifo | |
408 | */ | |
409 | static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel) | |
410 | { | |
411 | unsigned head; | |
412 | unsigned tail; | |
413 | ||
414 | head = GET_RX_CHANNEL_INFO(channel, head); | |
415 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
416 | ||
417 | return (head - tail) & (channel->fifo_size - 1); | |
418 | } | |
419 | ||
420 | /* | |
421 | * Set tx channel state and inform the remote processor | |
422 | */ | |
423 | static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel, | |
424 | int state) | |
425 | { | |
426 | struct qcom_smd_edge *edge = channel->edge; | |
427 | bool is_open = state == SMD_CHANNEL_OPENED; | |
428 | ||
429 | if (channel->state == state) | |
430 | return; | |
431 | ||
432 | dev_dbg(&edge->dev, "set_state(%s, %d)\n", channel->name, state); | |
433 | ||
434 | SET_TX_CHANNEL_FLAG(channel, fDSR, is_open); | |
435 | SET_TX_CHANNEL_FLAG(channel, fCTS, is_open); | |
436 | SET_TX_CHANNEL_FLAG(channel, fCD, is_open); | |
437 | ||
438 | SET_TX_CHANNEL_INFO(channel, state, state); | |
439 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); | |
440 | ||
441 | channel->state = state; | |
442 | qcom_smd_signal_channel(channel); | |
443 | } | |
444 | ||
445 | /* | |
446 | * Copy count bytes of data using 32bit accesses, if that's required. | |
447 | */ | |
448 | static void smd_copy_to_fifo(void __iomem *dst, | |
449 | const void *src, | |
450 | size_t count, | |
451 | bool word_aligned) | |
452 | { | |
453 | if (word_aligned) { | |
454 | __iowrite32_copy(dst, src, count / sizeof(u32)); | |
455 | } else { | |
456 | memcpy_toio(dst, src, count); | |
457 | } | |
458 | } | |
459 | ||
460 | /* | |
461 | * Copy count bytes of data using 32bit accesses, if that is required. | |
462 | */ | |
463 | static void smd_copy_from_fifo(void *dst, | |
464 | const void __iomem *src, | |
465 | size_t count, | |
466 | bool word_aligned) | |
467 | { | |
468 | if (word_aligned) { | |
469 | __ioread32_copy(dst, src, count / sizeof(u32)); | |
470 | } else { | |
471 | memcpy_fromio(dst, src, count); | |
472 | } | |
473 | } | |
474 | ||
475 | /* | |
476 | * Read count bytes of data from the rx fifo into buf, but don't advance the | |
477 | * tail. | |
478 | */ | |
479 | static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel, | |
480 | void *buf, size_t count) | |
481 | { | |
482 | bool word_aligned; | |
483 | unsigned tail; | |
484 | size_t len; | |
485 | ||
486 | word_aligned = channel->info_word; | |
487 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
488 | ||
489 | len = min_t(size_t, count, channel->fifo_size - tail); | |
490 | if (len) { | |
491 | smd_copy_from_fifo(buf, | |
492 | channel->rx_fifo + tail, | |
493 | len, | |
494 | word_aligned); | |
495 | } | |
496 | ||
497 | if (len != count) { | |
498 | smd_copy_from_fifo(buf + len, | |
499 | channel->rx_fifo, | |
500 | count - len, | |
501 | word_aligned); | |
502 | } | |
503 | ||
504 | return count; | |
505 | } | |
506 | ||
507 | /* | |
508 | * Advance the rx tail by count bytes. | |
509 | */ | |
510 | static void qcom_smd_channel_advance(struct qcom_smd_channel *channel, | |
511 | size_t count) | |
512 | { | |
513 | unsigned tail; | |
514 | ||
515 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
516 | tail += count; | |
517 | tail &= (channel->fifo_size - 1); | |
518 | SET_RX_CHANNEL_INFO(channel, tail, tail); | |
519 | } | |
520 | ||
521 | /* | |
522 | * Read out a single packet from the rx fifo and deliver it to the device | |
523 | */ | |
524 | static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel) | |
525 | { | |
526 | struct rpmsg_endpoint *ept = &channel->qsept->ept; | |
527 | unsigned tail; | |
528 | size_t len; | |
529 | void *ptr; | |
530 | int ret; | |
531 | ||
532 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
533 | ||
534 | /* Use bounce buffer if the data wraps */ | |
535 | if (tail + channel->pkt_size >= channel->fifo_size) { | |
536 | ptr = channel->bounce_buffer; | |
537 | len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size); | |
538 | } else { | |
539 | ptr = channel->rx_fifo + tail; | |
540 | len = channel->pkt_size; | |
541 | } | |
542 | ||
543 | ret = ept->cb(ept->rpdev, ptr, len, ept->priv, RPMSG_ADDR_ANY); | |
544 | if (ret < 0) | |
545 | return ret; | |
546 | ||
547 | /* Only forward the tail if the client consumed the data */ | |
548 | qcom_smd_channel_advance(channel, len); | |
549 | ||
550 | channel->pkt_size = 0; | |
551 | ||
552 | return 0; | |
553 | } | |
554 | ||
555 | /* | |
556 | * Per channel interrupt handling | |
557 | */ | |
558 | static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel) | |
559 | { | |
560 | bool need_state_scan = false; | |
561 | int remote_state; | |
562 | __le32 pktlen; | |
563 | int avail; | |
564 | int ret; | |
565 | ||
566 | /* Handle state changes */ | |
567 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
568 | if (remote_state != channel->remote_state) { | |
569 | channel->remote_state = remote_state; | |
570 | need_state_scan = true; | |
571 | } | |
572 | /* Indicate that we have seen any state change */ | |
573 | SET_RX_CHANNEL_FLAG(channel, fSTATE, 0); | |
574 | ||
575 | /* Signal waiting qcom_smd_send() about the interrupt */ | |
576 | if (!GET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) | |
577 | wake_up_interruptible(&channel->fblockread_event); | |
578 | ||
579 | /* Don't consume any data until we've opened the channel */ | |
580 | if (channel->state != SMD_CHANNEL_OPENED) | |
581 | goto out; | |
582 | ||
583 | /* Indicate that we've seen the new data */ | |
584 | SET_RX_CHANNEL_FLAG(channel, fHEAD, 0); | |
585 | ||
586 | /* Consume data */ | |
587 | for (;;) { | |
588 | avail = qcom_smd_channel_get_rx_avail(channel); | |
589 | ||
590 | if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) { | |
591 | qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen)); | |
592 | qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN); | |
593 | channel->pkt_size = le32_to_cpu(pktlen); | |
594 | } else if (channel->pkt_size && avail >= channel->pkt_size) { | |
595 | ret = qcom_smd_channel_recv_single(channel); | |
596 | if (ret) | |
597 | break; | |
598 | } else { | |
599 | break; | |
600 | } | |
601 | } | |
602 | ||
603 | /* Indicate that we have seen and updated tail */ | |
604 | SET_RX_CHANNEL_FLAG(channel, fTAIL, 1); | |
605 | ||
606 | /* Signal the remote that we've consumed the data (if requested) */ | |
607 | if (!GET_RX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) { | |
608 | /* Ensure ordering of channel info updates */ | |
609 | wmb(); | |
610 | ||
611 | qcom_smd_signal_channel(channel); | |
612 | } | |
613 | ||
614 | out: | |
615 | return need_state_scan; | |
616 | } | |
617 | ||
618 | /* | |
619 | * The edge interrupts are triggered by the remote processor on state changes, | |
620 | * channel info updates or when new channels are created. | |
621 | */ | |
622 | static irqreturn_t qcom_smd_edge_intr(int irq, void *data) | |
623 | { | |
624 | struct qcom_smd_edge *edge = data; | |
625 | struct qcom_smd_channel *channel; | |
626 | unsigned available; | |
627 | bool kick_scanner = false; | |
628 | bool kick_state = false; | |
629 | ||
630 | /* | |
631 | * Handle state changes or data on each of the channels on this edge | |
632 | */ | |
633 | spin_lock(&edge->channels_lock); | |
634 | list_for_each_entry(channel, &edge->channels, list) { | |
635 | spin_lock(&channel->recv_lock); | |
636 | kick_state |= qcom_smd_channel_intr(channel); | |
637 | spin_unlock(&channel->recv_lock); | |
638 | } | |
639 | spin_unlock(&edge->channels_lock); | |
640 | ||
641 | /* | |
642 | * Creating a new channel requires allocating an smem entry, so we only | |
643 | * have to scan if the amount of available space in smem have changed | |
644 | * since last scan. | |
645 | */ | |
646 | available = qcom_smem_get_free_space(edge->remote_pid); | |
647 | if (available != edge->smem_available) { | |
648 | edge->smem_available = available; | |
649 | kick_scanner = true; | |
650 | } | |
651 | ||
652 | if (kick_scanner) | |
653 | schedule_work(&edge->scan_work); | |
654 | if (kick_state) | |
655 | schedule_work(&edge->state_work); | |
656 | ||
657 | return IRQ_HANDLED; | |
658 | } | |
659 | ||
660 | /* | |
661 | * Calculate how much space is available in the tx fifo. | |
662 | */ | |
663 | static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel) | |
664 | { | |
665 | unsigned head; | |
666 | unsigned tail; | |
667 | unsigned mask = channel->fifo_size - 1; | |
668 | ||
669 | head = GET_TX_CHANNEL_INFO(channel, head); | |
670 | tail = GET_TX_CHANNEL_INFO(channel, tail); | |
671 | ||
672 | return mask - ((head - tail) & mask); | |
673 | } | |
674 | ||
675 | /* | |
676 | * Write count bytes of data into channel, possibly wrapping in the ring buffer | |
677 | */ | |
678 | static int qcom_smd_write_fifo(struct qcom_smd_channel *channel, | |
679 | const void *data, | |
680 | size_t count) | |
681 | { | |
682 | bool word_aligned; | |
683 | unsigned head; | |
684 | size_t len; | |
685 | ||
686 | word_aligned = channel->info_word; | |
687 | head = GET_TX_CHANNEL_INFO(channel, head); | |
688 | ||
689 | len = min_t(size_t, count, channel->fifo_size - head); | |
690 | if (len) { | |
691 | smd_copy_to_fifo(channel->tx_fifo + head, | |
692 | data, | |
693 | len, | |
694 | word_aligned); | |
695 | } | |
696 | ||
697 | if (len != count) { | |
698 | smd_copy_to_fifo(channel->tx_fifo, | |
699 | data + len, | |
700 | count - len, | |
701 | word_aligned); | |
702 | } | |
703 | ||
704 | head += count; | |
705 | head &= (channel->fifo_size - 1); | |
706 | SET_TX_CHANNEL_INFO(channel, head, head); | |
707 | ||
708 | return count; | |
709 | } | |
710 | ||
711 | /** | |
712 | * qcom_smd_send - write data to smd channel | |
713 | * @channel: channel handle | |
714 | * @data: buffer of data to write | |
715 | * @len: number of bytes to write | |
716 | * | |
717 | * This is a blocking write of len bytes into the channel's tx ring buffer and | |
718 | * signal the remote end. It will sleep until there is enough space available | |
719 | * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid | |
720 | * polling. | |
721 | */ | |
722 | static int __qcom_smd_send(struct qcom_smd_channel *channel, const void *data, | |
723 | int len, bool wait) | |
724 | { | |
725 | __le32 hdr[5] = { cpu_to_le32(len), }; | |
726 | int tlen = sizeof(hdr) + len; | |
727 | int ret; | |
728 | ||
729 | /* Word aligned channels only accept word size aligned data */ | |
730 | if (channel->info_word && len % 4) | |
731 | return -EINVAL; | |
732 | ||
733 | /* Reject packets that are too big */ | |
734 | if (tlen >= channel->fifo_size) | |
735 | return -EINVAL; | |
736 | ||
737 | ret = mutex_lock_interruptible(&channel->tx_lock); | |
738 | if (ret) | |
739 | return ret; | |
740 | ||
741 | while (qcom_smd_get_tx_avail(channel) < tlen) { | |
742 | if (!wait) { | |
1d74e7ed | 743 | ret = -EAGAIN; |
53e2822e BA |
744 | goto out; |
745 | } | |
746 | ||
747 | if (channel->state != SMD_CHANNEL_OPENED) { | |
748 | ret = -EPIPE; | |
749 | goto out; | |
750 | } | |
751 | ||
752 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 0); | |
753 | ||
754 | ret = wait_event_interruptible(channel->fblockread_event, | |
755 | qcom_smd_get_tx_avail(channel) >= tlen || | |
756 | channel->state != SMD_CHANNEL_OPENED); | |
757 | if (ret) | |
758 | goto out; | |
759 | ||
760 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); | |
761 | } | |
762 | ||
763 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); | |
764 | ||
765 | qcom_smd_write_fifo(channel, hdr, sizeof(hdr)); | |
766 | qcom_smd_write_fifo(channel, data, len); | |
767 | ||
768 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 1); | |
769 | ||
770 | /* Ensure ordering of channel info updates */ | |
771 | wmb(); | |
772 | ||
773 | qcom_smd_signal_channel(channel); | |
774 | ||
775 | out: | |
776 | mutex_unlock(&channel->tx_lock); | |
777 | ||
778 | return ret; | |
779 | } | |
780 | ||
781 | /* | |
782 | * Helper for opening a channel | |
783 | */ | |
784 | static int qcom_smd_channel_open(struct qcom_smd_channel *channel, | |
785 | rpmsg_rx_cb_t cb) | |
786 | { | |
787 | size_t bb_size; | |
788 | ||
789 | /* | |
790 | * Packets are maximum 4k, but reduce if the fifo is smaller | |
791 | */ | |
792 | bb_size = min(channel->fifo_size, SZ_4K); | |
793 | channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL); | |
794 | if (!channel->bounce_buffer) | |
795 | return -ENOMEM; | |
796 | ||
797 | qcom_smd_channel_set_callback(channel, cb); | |
798 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING); | |
799 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED); | |
800 | ||
801 | return 0; | |
802 | } | |
803 | ||
804 | /* | |
805 | * Helper for closing and resetting a channel | |
806 | */ | |
807 | static void qcom_smd_channel_close(struct qcom_smd_channel *channel) | |
808 | { | |
809 | qcom_smd_channel_set_callback(channel, NULL); | |
810 | ||
811 | kfree(channel->bounce_buffer); | |
812 | channel->bounce_buffer = NULL; | |
813 | ||
814 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); | |
815 | qcom_smd_channel_reset(channel); | |
816 | } | |
817 | ||
818 | static struct qcom_smd_channel * | |
819 | qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name) | |
820 | { | |
821 | struct qcom_smd_channel *channel; | |
822 | struct qcom_smd_channel *ret = NULL; | |
823 | unsigned long flags; | |
53e2822e BA |
824 | |
825 | spin_lock_irqsave(&edge->channels_lock, flags); | |
826 | list_for_each_entry(channel, &edge->channels, list) { | |
66dca399 BA |
827 | if (!strcmp(channel->name, name)) { |
828 | ret = channel; | |
829 | break; | |
830 | } | |
53e2822e BA |
831 | } |
832 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
833 | ||
834 | return ret; | |
835 | } | |
836 | ||
837 | static void __ept_release(struct kref *kref) | |
838 | { | |
839 | struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, | |
840 | refcount); | |
841 | kfree(to_smd_endpoint(ept)); | |
842 | } | |
843 | ||
844 | static struct rpmsg_endpoint *qcom_smd_create_ept(struct rpmsg_device *rpdev, | |
845 | rpmsg_rx_cb_t cb, void *priv, | |
846 | struct rpmsg_channel_info chinfo) | |
847 | { | |
848 | struct qcom_smd_endpoint *qsept; | |
849 | struct qcom_smd_channel *channel; | |
850 | struct qcom_smd_device *qsdev = to_smd_device(rpdev); | |
851 | struct qcom_smd_edge *edge = qsdev->edge; | |
852 | struct rpmsg_endpoint *ept; | |
853 | const char *name = chinfo.name; | |
854 | int ret; | |
855 | ||
856 | /* Wait up to HZ for the channel to appear */ | |
857 | ret = wait_event_interruptible_timeout(edge->new_channel_event, | |
858 | (channel = qcom_smd_find_channel(edge, name)) != NULL, | |
859 | HZ); | |
860 | if (!ret) | |
861 | return NULL; | |
862 | ||
863 | if (channel->state != SMD_CHANNEL_CLOSED) { | |
864 | dev_err(&rpdev->dev, "channel %s is busy\n", channel->name); | |
865 | return NULL; | |
866 | } | |
867 | ||
868 | qsept = kzalloc(sizeof(*qsept), GFP_KERNEL); | |
869 | if (!qsept) | |
870 | return NULL; | |
871 | ||
872 | ept = &qsept->ept; | |
873 | ||
874 | kref_init(&ept->refcount); | |
875 | ||
876 | ept->rpdev = rpdev; | |
877 | ept->cb = cb; | |
878 | ept->priv = priv; | |
879 | ept->ops = &qcom_smd_endpoint_ops; | |
880 | ||
881 | channel->qsept = qsept; | |
882 | qsept->qsch = channel; | |
883 | ||
884 | ret = qcom_smd_channel_open(channel, cb); | |
885 | if (ret) | |
886 | goto free_ept; | |
887 | ||
888 | return ept; | |
889 | ||
890 | free_ept: | |
891 | channel->qsept = NULL; | |
892 | kref_put(&ept->refcount, __ept_release); | |
893 | return NULL; | |
894 | } | |
895 | ||
896 | static void qcom_smd_destroy_ept(struct rpmsg_endpoint *ept) | |
897 | { | |
898 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
899 | struct qcom_smd_channel *ch = qsept->qsch; | |
900 | ||
901 | qcom_smd_channel_close(ch); | |
902 | ch->qsept = NULL; | |
903 | kref_put(&ept->refcount, __ept_release); | |
904 | } | |
905 | ||
906 | static int qcom_smd_send(struct rpmsg_endpoint *ept, void *data, int len) | |
907 | { | |
908 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
909 | ||
910 | return __qcom_smd_send(qsept->qsch, data, len, true); | |
911 | } | |
912 | ||
913 | static int qcom_smd_trysend(struct rpmsg_endpoint *ept, void *data, int len) | |
914 | { | |
915 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
916 | ||
917 | return __qcom_smd_send(qsept->qsch, data, len, false); | |
918 | } | |
919 | ||
920 | /* | |
921 | * Finds the device_node for the smd child interested in this channel. | |
922 | */ | |
923 | static struct device_node *qcom_smd_match_channel(struct device_node *edge_node, | |
924 | const char *channel) | |
925 | { | |
926 | struct device_node *child; | |
927 | const char *name; | |
928 | const char *key; | |
929 | int ret; | |
930 | ||
931 | for_each_available_child_of_node(edge_node, child) { | |
932 | key = "qcom,smd-channels"; | |
933 | ret = of_property_read_string(child, key, &name); | |
934 | if (ret) | |
935 | continue; | |
936 | ||
937 | if (strcmp(name, channel) == 0) | |
938 | return child; | |
939 | } | |
940 | ||
941 | return NULL; | |
942 | } | |
943 | ||
944 | static const struct rpmsg_device_ops qcom_smd_device_ops = { | |
945 | .create_ept = qcom_smd_create_ept, | |
946 | }; | |
947 | ||
948 | static const struct rpmsg_endpoint_ops qcom_smd_endpoint_ops = { | |
949 | .destroy_ept = qcom_smd_destroy_ept, | |
950 | .send = qcom_smd_send, | |
951 | .trysend = qcom_smd_trysend, | |
952 | }; | |
953 | ||
954 | /* | |
955 | * Create a smd client device for channel that is being opened. | |
956 | */ | |
957 | static int qcom_smd_create_device(struct qcom_smd_channel *channel) | |
958 | { | |
959 | struct qcom_smd_device *qsdev; | |
960 | struct rpmsg_device *rpdev; | |
961 | struct qcom_smd_edge *edge = channel->edge; | |
962 | ||
963 | dev_dbg(&edge->dev, "registering '%s'\n", channel->name); | |
964 | ||
965 | qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL); | |
966 | if (!qsdev) | |
967 | return -ENOMEM; | |
968 | ||
969 | /* Link qsdev to our SMD edge */ | |
970 | qsdev->edge = edge; | |
971 | ||
972 | /* Assign callbacks for rpmsg_device */ | |
973 | qsdev->rpdev.ops = &qcom_smd_device_ops; | |
974 | ||
975 | /* Assign public information to the rpmsg_device */ | |
976 | rpdev = &qsdev->rpdev; | |
977 | strncpy(rpdev->id.name, channel->name, RPMSG_NAME_SIZE); | |
978 | rpdev->src = RPMSG_ADDR_ANY; | |
979 | rpdev->dst = RPMSG_ADDR_ANY; | |
980 | ||
981 | rpdev->dev.of_node = qcom_smd_match_channel(edge->of_node, channel->name); | |
982 | rpdev->dev.parent = &edge->dev; | |
983 | ||
984 | return rpmsg_register_device(rpdev); | |
985 | } | |
986 | ||
987 | /* | |
988 | * Allocate the qcom_smd_channel object for a newly found smd channel, | |
989 | * retrieving and validating the smem items involved. | |
990 | */ | |
991 | static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge, | |
992 | unsigned smem_info_item, | |
993 | unsigned smem_fifo_item, | |
994 | char *name) | |
995 | { | |
996 | struct qcom_smd_channel *channel; | |
997 | size_t fifo_size; | |
998 | size_t info_size; | |
999 | void *fifo_base; | |
1000 | void *info; | |
1001 | int ret; | |
1002 | ||
1003 | channel = devm_kzalloc(&edge->dev, sizeof(*channel), GFP_KERNEL); | |
1004 | if (!channel) | |
1005 | return ERR_PTR(-ENOMEM); | |
1006 | ||
1007 | channel->edge = edge; | |
1008 | channel->name = devm_kstrdup(&edge->dev, name, GFP_KERNEL); | |
1009 | if (!channel->name) | |
1010 | return ERR_PTR(-ENOMEM); | |
1011 | ||
1012 | mutex_init(&channel->tx_lock); | |
1013 | spin_lock_init(&channel->recv_lock); | |
1014 | init_waitqueue_head(&channel->fblockread_event); | |
1015 | ||
1016 | info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size); | |
1017 | if (IS_ERR(info)) { | |
1018 | ret = PTR_ERR(info); | |
1019 | goto free_name_and_channel; | |
1020 | } | |
1021 | ||
1022 | /* | |
1023 | * Use the size of the item to figure out which channel info struct to | |
1024 | * use. | |
1025 | */ | |
1026 | if (info_size == 2 * sizeof(struct smd_channel_info_word)) { | |
1027 | channel->info_word = info; | |
1028 | } else if (info_size == 2 * sizeof(struct smd_channel_info)) { | |
1029 | channel->info = info; | |
1030 | } else { | |
1031 | dev_err(&edge->dev, | |
1032 | "channel info of size %zu not supported\n", info_size); | |
1033 | ret = -EINVAL; | |
1034 | goto free_name_and_channel; | |
1035 | } | |
1036 | ||
1037 | fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size); | |
1038 | if (IS_ERR(fifo_base)) { | |
1039 | ret = PTR_ERR(fifo_base); | |
1040 | goto free_name_and_channel; | |
1041 | } | |
1042 | ||
1043 | /* The channel consist of a rx and tx fifo of equal size */ | |
1044 | fifo_size /= 2; | |
1045 | ||
1046 | dev_dbg(&edge->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n", | |
1047 | name, info_size, fifo_size); | |
1048 | ||
1049 | channel->tx_fifo = fifo_base; | |
1050 | channel->rx_fifo = fifo_base + fifo_size; | |
1051 | channel->fifo_size = fifo_size; | |
1052 | ||
1053 | qcom_smd_channel_reset(channel); | |
1054 | ||
1055 | return channel; | |
1056 | ||
1057 | free_name_and_channel: | |
1058 | devm_kfree(&edge->dev, channel->name); | |
1059 | devm_kfree(&edge->dev, channel); | |
1060 | ||
1061 | return ERR_PTR(ret); | |
1062 | } | |
1063 | ||
1064 | /* | |
1065 | * Scans the allocation table for any newly allocated channels, calls | |
1066 | * qcom_smd_create_channel() to create representations of these and add | |
1067 | * them to the edge's list of channels. | |
1068 | */ | |
1069 | static void qcom_channel_scan_worker(struct work_struct *work) | |
1070 | { | |
1071 | struct qcom_smd_edge *edge = container_of(work, struct qcom_smd_edge, scan_work); | |
1072 | struct qcom_smd_alloc_entry *alloc_tbl; | |
1073 | struct qcom_smd_alloc_entry *entry; | |
1074 | struct qcom_smd_channel *channel; | |
1075 | unsigned long flags; | |
1076 | unsigned fifo_id; | |
1077 | unsigned info_id; | |
1078 | int tbl; | |
1079 | int i; | |
1080 | u32 eflags, cid; | |
1081 | ||
1082 | for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) { | |
1083 | alloc_tbl = qcom_smem_get(edge->remote_pid, | |
1084 | smem_items[tbl].alloc_tbl_id, NULL); | |
1085 | if (IS_ERR(alloc_tbl)) | |
1086 | continue; | |
1087 | ||
1088 | for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) { | |
1089 | entry = &alloc_tbl[i]; | |
1090 | eflags = le32_to_cpu(entry->flags); | |
1091 | if (test_bit(i, edge->allocated[tbl])) | |
1092 | continue; | |
1093 | ||
1094 | if (entry->ref_count == 0) | |
1095 | continue; | |
1096 | ||
1097 | if (!entry->name[0]) | |
1098 | continue; | |
1099 | ||
1100 | if (!(eflags & SMD_CHANNEL_FLAGS_PACKET)) | |
1101 | continue; | |
1102 | ||
1103 | if ((eflags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id) | |
1104 | continue; | |
1105 | ||
1106 | cid = le32_to_cpu(entry->cid); | |
1107 | info_id = smem_items[tbl].info_base_id + cid; | |
1108 | fifo_id = smem_items[tbl].fifo_base_id + cid; | |
1109 | ||
1110 | channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name); | |
1111 | if (IS_ERR(channel)) | |
1112 | continue; | |
1113 | ||
1114 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1115 | list_add(&channel->list, &edge->channels); | |
1116 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1117 | ||
1118 | dev_dbg(&edge->dev, "new channel found: '%s'\n", channel->name); | |
1119 | set_bit(i, edge->allocated[tbl]); | |
1120 | ||
1121 | wake_up_interruptible(&edge->new_channel_event); | |
1122 | } | |
1123 | } | |
1124 | ||
1125 | schedule_work(&edge->state_work); | |
1126 | } | |
1127 | ||
1128 | /* | |
1129 | * This per edge worker scans smem for any new channels and register these. It | |
1130 | * then scans all registered channels for state changes that should be handled | |
1131 | * by creating or destroying smd client devices for the registered channels. | |
1132 | * | |
1133 | * LOCKING: edge->channels_lock only needs to cover the list operations, as the | |
1134 | * worker is killed before any channels are deallocated | |
1135 | */ | |
1136 | static void qcom_channel_state_worker(struct work_struct *work) | |
1137 | { | |
1138 | struct qcom_smd_channel *channel; | |
1139 | struct qcom_smd_edge *edge = container_of(work, | |
1140 | struct qcom_smd_edge, | |
1141 | state_work); | |
1142 | struct rpmsg_channel_info chinfo; | |
1143 | unsigned remote_state; | |
1144 | unsigned long flags; | |
1145 | ||
1146 | /* | |
1147 | * Register a device for any closed channel where the remote processor | |
1148 | * is showing interest in opening the channel. | |
1149 | */ | |
1150 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1151 | list_for_each_entry(channel, &edge->channels, list) { | |
1152 | if (channel->state != SMD_CHANNEL_CLOSED) | |
1153 | continue; | |
1154 | ||
1155 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1156 | if (remote_state != SMD_CHANNEL_OPENING && | |
1157 | remote_state != SMD_CHANNEL_OPENED) | |
1158 | continue; | |
1159 | ||
1160 | if (channel->registered) | |
1161 | continue; | |
1162 | ||
1163 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1164 | qcom_smd_create_device(channel); | |
1165 | channel->registered = true; | |
1166 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1167 | ||
1168 | channel->registered = true; | |
1169 | } | |
1170 | ||
1171 | /* | |
1172 | * Unregister the device for any channel that is opened where the | |
1173 | * remote processor is closing the channel. | |
1174 | */ | |
1175 | list_for_each_entry(channel, &edge->channels, list) { | |
1176 | if (channel->state != SMD_CHANNEL_OPENING && | |
1177 | channel->state != SMD_CHANNEL_OPENED) | |
1178 | continue; | |
1179 | ||
1180 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1181 | if (remote_state == SMD_CHANNEL_OPENING || | |
1182 | remote_state == SMD_CHANNEL_OPENED) | |
1183 | continue; | |
1184 | ||
1185 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1186 | ||
1187 | strncpy(chinfo.name, channel->name, sizeof(chinfo.name)); | |
1188 | chinfo.src = RPMSG_ADDR_ANY; | |
1189 | chinfo.dst = RPMSG_ADDR_ANY; | |
1190 | rpmsg_unregister_device(&edge->dev, &chinfo); | |
1191 | channel->registered = false; | |
1192 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1193 | } | |
1194 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1195 | } | |
1196 | ||
1197 | /* | |
1198 | * Parses an of_node describing an edge. | |
1199 | */ | |
1200 | static int qcom_smd_parse_edge(struct device *dev, | |
1201 | struct device_node *node, | |
1202 | struct qcom_smd_edge *edge) | |
1203 | { | |
1204 | struct device_node *syscon_np; | |
1205 | const char *key; | |
1206 | int irq; | |
1207 | int ret; | |
1208 | ||
1209 | INIT_LIST_HEAD(&edge->channels); | |
1210 | spin_lock_init(&edge->channels_lock); | |
1211 | ||
1212 | INIT_WORK(&edge->scan_work, qcom_channel_scan_worker); | |
1213 | INIT_WORK(&edge->state_work, qcom_channel_state_worker); | |
1214 | ||
1215 | edge->of_node = of_node_get(node); | |
1216 | ||
1217 | key = "qcom,smd-edge"; | |
1218 | ret = of_property_read_u32(node, key, &edge->edge_id); | |
1219 | if (ret) { | |
1220 | dev_err(dev, "edge missing %s property\n", key); | |
1221 | return -EINVAL; | |
1222 | } | |
1223 | ||
1224 | edge->remote_pid = QCOM_SMEM_HOST_ANY; | |
1225 | key = "qcom,remote-pid"; | |
1226 | of_property_read_u32(node, key, &edge->remote_pid); | |
1227 | ||
1228 | syscon_np = of_parse_phandle(node, "qcom,ipc", 0); | |
1229 | if (!syscon_np) { | |
1230 | dev_err(dev, "no qcom,ipc node\n"); | |
1231 | return -ENODEV; | |
1232 | } | |
1233 | ||
1234 | edge->ipc_regmap = syscon_node_to_regmap(syscon_np); | |
1235 | if (IS_ERR(edge->ipc_regmap)) | |
1236 | return PTR_ERR(edge->ipc_regmap); | |
1237 | ||
1238 | key = "qcom,ipc"; | |
1239 | ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset); | |
1240 | if (ret < 0) { | |
1241 | dev_err(dev, "no offset in %s\n", key); | |
1242 | return -EINVAL; | |
1243 | } | |
1244 | ||
1245 | ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit); | |
1246 | if (ret < 0) { | |
1247 | dev_err(dev, "no bit in %s\n", key); | |
1248 | return -EINVAL; | |
1249 | } | |
1250 | ||
1251 | irq = irq_of_parse_and_map(node, 0); | |
1252 | if (irq < 0) { | |
1253 | dev_err(dev, "required smd interrupt missing\n"); | |
1254 | return -EINVAL; | |
1255 | } | |
1256 | ||
1257 | ret = devm_request_irq(dev, irq, | |
1258 | qcom_smd_edge_intr, IRQF_TRIGGER_RISING, | |
1259 | node->name, edge); | |
1260 | if (ret) { | |
1261 | dev_err(dev, "failed to request smd irq\n"); | |
1262 | return ret; | |
1263 | } | |
1264 | ||
1265 | edge->irq = irq; | |
1266 | ||
1267 | return 0; | |
1268 | } | |
1269 | ||
1270 | /* | |
1271 | * Release function for an edge. | |
1272 | * Reset the state of each associated channel and free the edge context. | |
1273 | */ | |
1274 | static void qcom_smd_edge_release(struct device *dev) | |
1275 | { | |
1276 | struct qcom_smd_channel *channel; | |
1277 | struct qcom_smd_edge *edge = to_smd_edge(dev); | |
1278 | ||
1279 | list_for_each_entry(channel, &edge->channels, list) { | |
1280 | SET_RX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); | |
1281 | SET_RX_CHANNEL_INFO(channel, head, 0); | |
1282 | SET_RX_CHANNEL_INFO(channel, tail, 0); | |
1283 | } | |
1284 | ||
1285 | kfree(edge); | |
1286 | } | |
1287 | ||
1288 | /** | |
1289 | * qcom_smd_register_edge() - register an edge based on an device_node | |
1290 | * @parent: parent device for the edge | |
1291 | * @node: device_node describing the edge | |
1292 | * | |
1293 | * Returns an edge reference, or negative ERR_PTR() on failure. | |
1294 | */ | |
1295 | struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent, | |
1296 | struct device_node *node) | |
1297 | { | |
1298 | struct qcom_smd_edge *edge; | |
1299 | int ret; | |
1300 | ||
1301 | edge = kzalloc(sizeof(*edge), GFP_KERNEL); | |
1302 | if (!edge) | |
1303 | return ERR_PTR(-ENOMEM); | |
1304 | ||
1305 | init_waitqueue_head(&edge->new_channel_event); | |
1306 | ||
1307 | edge->dev.parent = parent; | |
1308 | edge->dev.release = qcom_smd_edge_release; | |
1309 | dev_set_name(&edge->dev, "%s:%s", dev_name(parent), node->name); | |
1310 | ret = device_register(&edge->dev); | |
1311 | if (ret) { | |
1312 | pr_err("failed to register smd edge\n"); | |
1313 | return ERR_PTR(ret); | |
1314 | } | |
1315 | ||
1316 | ret = qcom_smd_parse_edge(&edge->dev, node, edge); | |
1317 | if (ret) { | |
1318 | dev_err(&edge->dev, "failed to parse smd edge\n"); | |
1319 | goto unregister_dev; | |
1320 | } | |
1321 | ||
1322 | schedule_work(&edge->scan_work); | |
1323 | ||
1324 | return edge; | |
1325 | ||
1326 | unregister_dev: | |
1327 | put_device(&edge->dev); | |
1328 | return ERR_PTR(ret); | |
1329 | } | |
1330 | EXPORT_SYMBOL(qcom_smd_register_edge); | |
1331 | ||
1332 | static int qcom_smd_remove_device(struct device *dev, void *data) | |
1333 | { | |
1334 | device_unregister(dev); | |
1335 | ||
1336 | return 0; | |
1337 | } | |
1338 | ||
1339 | /** | |
1340 | * qcom_smd_unregister_edge() - release an edge and its children | |
1341 | * @edge: edge reference acquired from qcom_smd_register_edge | |
1342 | */ | |
1343 | int qcom_smd_unregister_edge(struct qcom_smd_edge *edge) | |
1344 | { | |
1345 | int ret; | |
1346 | ||
1347 | disable_irq(edge->irq); | |
1348 | cancel_work_sync(&edge->scan_work); | |
1349 | cancel_work_sync(&edge->state_work); | |
1350 | ||
1351 | ret = device_for_each_child(&edge->dev, NULL, qcom_smd_remove_device); | |
1352 | if (ret) | |
1353 | dev_warn(&edge->dev, "can't remove smd device: %d\n", ret); | |
1354 | ||
1355 | device_unregister(&edge->dev); | |
1356 | ||
1357 | return 0; | |
1358 | } | |
1359 | EXPORT_SYMBOL(qcom_smd_unregister_edge); | |
1360 | ||
1361 | static int qcom_smd_probe(struct platform_device *pdev) | |
1362 | { | |
1363 | struct device_node *node; | |
1364 | void *p; | |
1365 | ||
1366 | /* Wait for smem */ | |
1367 | p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL); | |
1368 | if (PTR_ERR(p) == -EPROBE_DEFER) | |
1369 | return PTR_ERR(p); | |
1370 | ||
1371 | for_each_available_child_of_node(pdev->dev.of_node, node) | |
1372 | qcom_smd_register_edge(&pdev->dev, node); | |
1373 | ||
1374 | return 0; | |
1375 | } | |
1376 | ||
1377 | static int qcom_smd_remove_edge(struct device *dev, void *data) | |
1378 | { | |
1379 | struct qcom_smd_edge *edge = to_smd_edge(dev); | |
1380 | ||
1381 | return qcom_smd_unregister_edge(edge); | |
1382 | } | |
1383 | ||
1384 | /* | |
1385 | * Shut down all smd clients by making sure that each edge stops processing | |
1386 | * events and scanning for new channels, then call destroy on the devices. | |
1387 | */ | |
1388 | static int qcom_smd_remove(struct platform_device *pdev) | |
1389 | { | |
1390 | int ret; | |
1391 | ||
1392 | ret = device_for_each_child(&pdev->dev, NULL, qcom_smd_remove_edge); | |
1393 | if (ret) | |
1394 | dev_warn(&pdev->dev, "can't remove smd device: %d\n", ret); | |
1395 | ||
1396 | return ret; | |
1397 | } | |
1398 | ||
1399 | static const struct of_device_id qcom_smd_of_match[] = { | |
1400 | { .compatible = "qcom,smd" }, | |
1401 | {} | |
1402 | }; | |
1403 | MODULE_DEVICE_TABLE(of, qcom_smd_of_match); | |
1404 | ||
1405 | static struct platform_driver qcom_smd_driver = { | |
1406 | .probe = qcom_smd_probe, | |
1407 | .remove = qcom_smd_remove, | |
1408 | .driver = { | |
1409 | .name = "qcom-smd", | |
1410 | .of_match_table = qcom_smd_of_match, | |
1411 | }, | |
1412 | }; | |
1413 | ||
1414 | static int __init qcom_smd_init(void) | |
1415 | { | |
1416 | return platform_driver_register(&qcom_smd_driver); | |
1417 | } | |
1418 | subsys_initcall(qcom_smd_init); | |
1419 | ||
1420 | static void __exit qcom_smd_exit(void) | |
1421 | { | |
1422 | platform_driver_unregister(&qcom_smd_driver); | |
1423 | } | |
1424 | module_exit(qcom_smd_exit); | |
1425 | ||
1426 | MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); | |
1427 | MODULE_DESCRIPTION("Qualcomm Shared Memory Driver"); | |
1428 | MODULE_LICENSE("GPL v2"); |