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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> | |
28 | ||
29 | #include "rpmsg_internal.h" | |
30 | ||
31 | /* | |
32 | * The Qualcomm Shared Memory communication solution provides point-to-point | |
33 | * channels for clients to send and receive streaming or packet based data. | |
34 | * | |
35 | * Each channel consists of a control item (channel info) and a ring buffer | |
36 | * pair. The channel info carry information related to channel state, flow | |
37 | * control and the offsets within the ring buffer. | |
38 | * | |
39 | * All allocated channels are listed in an allocation table, identifying the | |
40 | * pair of items by name, type and remote processor. | |
41 | * | |
42 | * Upon creating a new channel the remote processor allocates channel info and | |
43 | * ring buffer items from the smem heap and populate the allocation table. An | |
44 | * interrupt is sent to the other end of the channel and a scan for new | |
45 | * channels should be done. A channel never goes away, it will only change | |
46 | * state. | |
47 | * | |
48 | * The remote processor signals it intent for bring up the communication | |
49 | * channel by setting the state of its end of the channel to "opening" and | |
50 | * sends out an interrupt. We detect this change and register a smd device to | |
51 | * consume the channel. Upon finding a consumer we finish the handshake and the | |
52 | * channel is up. | |
53 | * | |
54 | * Upon closing a channel, the remote processor will update the state of its | |
55 | * end of the channel and signal us, we will then unregister any attached | |
56 | * device and close our end of the channel. | |
57 | * | |
58 | * Devices attached to a channel can use the qcom_smd_send function to push | |
59 | * data to the channel, this is done by copying the data into the tx ring | |
60 | * buffer, updating the pointers in the channel info and signaling the remote | |
61 | * processor. | |
62 | * | |
63 | * The remote processor does the equivalent when it transfer data and upon | |
64 | * receiving the interrupt we check the channel info for new data and delivers | |
65 | * this to the attached device. If the device is not ready to receive the data | |
66 | * we leave it in the ring buffer for now. | |
67 | */ | |
68 | ||
69 | struct smd_channel_info; | |
70 | struct smd_channel_info_pair; | |
71 | struct smd_channel_info_word; | |
72 | struct smd_channel_info_word_pair; | |
73 | ||
74 | static const struct rpmsg_endpoint_ops qcom_smd_endpoint_ops; | |
75 | ||
76 | #define SMD_ALLOC_TBL_COUNT 2 | |
77 | #define SMD_ALLOC_TBL_SIZE 64 | |
78 | ||
79 | /* | |
80 | * This lists the various smem heap items relevant for the allocation table and | |
81 | * smd channel entries. | |
82 | */ | |
83 | static const struct { | |
84 | unsigned alloc_tbl_id; | |
85 | unsigned info_base_id; | |
86 | unsigned fifo_base_id; | |
87 | } smem_items[SMD_ALLOC_TBL_COUNT] = { | |
88 | { | |
89 | .alloc_tbl_id = 13, | |
90 | .info_base_id = 14, | |
91 | .fifo_base_id = 338 | |
92 | }, | |
93 | { | |
94 | .alloc_tbl_id = 266, | |
95 | .info_base_id = 138, | |
96 | .fifo_base_id = 202, | |
97 | }, | |
98 | }; | |
99 | ||
100 | /** | |
101 | * struct qcom_smd_edge - representing a remote processor | |
102 | * @of_node: of_node handle for information related to this edge | |
103 | * @edge_id: identifier of this edge | |
104 | * @remote_pid: identifier of remote processor | |
105 | * @irq: interrupt for signals on this edge | |
106 | * @ipc_regmap: regmap handle holding the outgoing ipc register | |
107 | * @ipc_offset: offset within @ipc_regmap of the register for ipc | |
108 | * @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap | |
109 | * @channels: list of all channels detected on this edge | |
110 | * @channels_lock: guard for modifications of @channels | |
111 | * @allocated: array of bitmaps representing already allocated channels | |
112 | * @smem_available: last available amount of smem triggering a channel scan | |
113 | * @scan_work: work item for discovering new channels | |
114 | * @state_work: work item for edge state changes | |
115 | */ | |
116 | struct qcom_smd_edge { | |
117 | struct device dev; | |
118 | ||
119 | struct device_node *of_node; | |
120 | unsigned edge_id; | |
121 | unsigned remote_pid; | |
122 | ||
123 | int irq; | |
124 | ||
125 | struct regmap *ipc_regmap; | |
126 | int ipc_offset; | |
127 | int ipc_bit; | |
128 | ||
129 | struct list_head channels; | |
130 | spinlock_t channels_lock; | |
131 | ||
132 | DECLARE_BITMAP(allocated[SMD_ALLOC_TBL_COUNT], SMD_ALLOC_TBL_SIZE); | |
133 | ||
134 | unsigned smem_available; | |
135 | ||
136 | wait_queue_head_t new_channel_event; | |
137 | ||
138 | struct work_struct scan_work; | |
139 | struct work_struct state_work; | |
140 | }; | |
141 | ||
142 | /* | |
143 | * SMD channel states. | |
144 | */ | |
145 | enum smd_channel_state { | |
146 | SMD_CHANNEL_CLOSED, | |
147 | SMD_CHANNEL_OPENING, | |
148 | SMD_CHANNEL_OPENED, | |
149 | SMD_CHANNEL_FLUSHING, | |
150 | SMD_CHANNEL_CLOSING, | |
151 | SMD_CHANNEL_RESET, | |
152 | SMD_CHANNEL_RESET_OPENING | |
153 | }; | |
154 | ||
155 | struct qcom_smd_device { | |
156 | struct rpmsg_device rpdev; | |
157 | ||
158 | struct qcom_smd_edge *edge; | |
159 | }; | |
160 | ||
161 | struct qcom_smd_endpoint { | |
162 | struct rpmsg_endpoint ept; | |
163 | ||
164 | struct qcom_smd_channel *qsch; | |
165 | }; | |
166 | ||
167 | #define to_smd_device(_rpdev) container_of(_rpdev, struct qcom_smd_device, rpdev) | |
168 | #define to_smd_edge(d) container_of(d, struct qcom_smd_edge, dev) | |
169 | #define to_smd_endpoint(ept) container_of(ept, struct qcom_smd_endpoint, ept) | |
170 | ||
171 | /** | |
172 | * struct qcom_smd_channel - smd channel struct | |
173 | * @edge: qcom_smd_edge this channel is living on | |
174 | * @qsdev: reference to a associated smd client device | |
175 | * @name: name of the channel | |
176 | * @state: local state of the channel | |
177 | * @remote_state: remote state of the channel | |
178 | * @info: byte aligned outgoing/incoming channel info | |
179 | * @info_word: word aligned outgoing/incoming channel info | |
180 | * @tx_lock: lock to make writes to the channel mutually exclusive | |
181 | * @fblockread_event: wakeup event tied to tx fBLOCKREADINTR | |
182 | * @tx_fifo: pointer to the outgoing ring buffer | |
183 | * @rx_fifo: pointer to the incoming ring buffer | |
184 | * @fifo_size: size of each ring buffer | |
185 | * @bounce_buffer: bounce buffer for reading wrapped packets | |
186 | * @cb: callback function registered for this channel | |
187 | * @recv_lock: guard for rx info modifications and cb pointer | |
188 | * @pkt_size: size of the currently handled packet | |
189 | * @list: lite entry for @channels in qcom_smd_edge | |
190 | */ | |
191 | struct qcom_smd_channel { | |
192 | struct qcom_smd_edge *edge; | |
193 | ||
194 | struct qcom_smd_endpoint *qsept; | |
195 | bool registered; | |
196 | ||
197 | char *name; | |
198 | enum smd_channel_state state; | |
199 | enum smd_channel_state remote_state; | |
200 | ||
201 | struct smd_channel_info_pair *info; | |
202 | struct smd_channel_info_word_pair *info_word; | |
203 | ||
204 | struct mutex tx_lock; | |
205 | wait_queue_head_t fblockread_event; | |
206 | ||
207 | void *tx_fifo; | |
208 | void *rx_fifo; | |
209 | int fifo_size; | |
210 | ||
211 | void *bounce_buffer; | |
212 | ||
213 | spinlock_t recv_lock; | |
214 | ||
215 | int pkt_size; | |
216 | ||
217 | void *drvdata; | |
218 | ||
219 | struct list_head list; | |
220 | }; | |
221 | ||
222 | /* | |
223 | * Format of the smd_info smem items, for byte aligned channels. | |
224 | */ | |
225 | struct smd_channel_info { | |
226 | __le32 state; | |
227 | u8 fDSR; | |
228 | u8 fCTS; | |
229 | u8 fCD; | |
230 | u8 fRI; | |
231 | u8 fHEAD; | |
232 | u8 fTAIL; | |
233 | u8 fSTATE; | |
234 | u8 fBLOCKREADINTR; | |
235 | __le32 tail; | |
236 | __le32 head; | |
237 | }; | |
238 | ||
239 | struct smd_channel_info_pair { | |
240 | struct smd_channel_info tx; | |
241 | struct smd_channel_info rx; | |
242 | }; | |
243 | ||
244 | /* | |
245 | * Format of the smd_info smem items, for word aligned channels. | |
246 | */ | |
247 | struct smd_channel_info_word { | |
248 | __le32 state; | |
249 | __le32 fDSR; | |
250 | __le32 fCTS; | |
251 | __le32 fCD; | |
252 | __le32 fRI; | |
253 | __le32 fHEAD; | |
254 | __le32 fTAIL; | |
255 | __le32 fSTATE; | |
256 | __le32 fBLOCKREADINTR; | |
257 | __le32 tail; | |
258 | __le32 head; | |
259 | }; | |
260 | ||
261 | struct smd_channel_info_word_pair { | |
262 | struct smd_channel_info_word tx; | |
263 | struct smd_channel_info_word rx; | |
264 | }; | |
265 | ||
266 | #define GET_RX_CHANNEL_FLAG(channel, param) \ | |
267 | ({ \ | |
268 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
269 | channel->info_word ? \ | |
270 | le32_to_cpu(channel->info_word->rx.param) : \ | |
271 | channel->info->rx.param; \ | |
272 | }) | |
273 | ||
274 | #define GET_RX_CHANNEL_INFO(channel, param) \ | |
275 | ({ \ | |
276 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
277 | le32_to_cpu(channel->info_word ? \ | |
278 | channel->info_word->rx.param : \ | |
279 | channel->info->rx.param); \ | |
280 | }) | |
281 | ||
282 | #define SET_RX_CHANNEL_FLAG(channel, param, value) \ | |
283 | ({ \ | |
284 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u8)); \ | |
285 | if (channel->info_word) \ | |
286 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
287 | else \ | |
288 | channel->info->rx.param = value; \ | |
289 | }) | |
290 | ||
291 | #define SET_RX_CHANNEL_INFO(channel, param, value) \ | |
292 | ({ \ | |
293 | BUILD_BUG_ON(sizeof(channel->info->rx.param) != sizeof(u32)); \ | |
294 | if (channel->info_word) \ | |
295 | channel->info_word->rx.param = cpu_to_le32(value); \ | |
296 | else \ | |
297 | channel->info->rx.param = cpu_to_le32(value); \ | |
298 | }) | |
299 | ||
300 | #define GET_TX_CHANNEL_FLAG(channel, param) \ | |
301 | ({ \ | |
302 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
303 | channel->info_word ? \ | |
304 | le32_to_cpu(channel->info_word->tx.param) : \ | |
305 | channel->info->tx.param; \ | |
306 | }) | |
307 | ||
308 | #define GET_TX_CHANNEL_INFO(channel, param) \ | |
309 | ({ \ | |
310 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
311 | le32_to_cpu(channel->info_word ? \ | |
312 | channel->info_word->tx.param : \ | |
313 | channel->info->tx.param); \ | |
314 | }) | |
315 | ||
316 | #define SET_TX_CHANNEL_FLAG(channel, param, value) \ | |
317 | ({ \ | |
318 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u8)); \ | |
319 | if (channel->info_word) \ | |
320 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
321 | else \ | |
322 | channel->info->tx.param = value; \ | |
323 | }) | |
324 | ||
325 | #define SET_TX_CHANNEL_INFO(channel, param, value) \ | |
326 | ({ \ | |
327 | BUILD_BUG_ON(sizeof(channel->info->tx.param) != sizeof(u32)); \ | |
328 | if (channel->info_word) \ | |
329 | channel->info_word->tx.param = cpu_to_le32(value); \ | |
330 | else \ | |
331 | channel->info->tx.param = cpu_to_le32(value); \ | |
332 | }) | |
333 | ||
334 | /** | |
335 | * struct qcom_smd_alloc_entry - channel allocation entry | |
336 | * @name: channel name | |
337 | * @cid: channel index | |
338 | * @flags: channel flags and edge id | |
339 | * @ref_count: reference count of the channel | |
340 | */ | |
341 | struct qcom_smd_alloc_entry { | |
342 | u8 name[20]; | |
343 | __le32 cid; | |
344 | __le32 flags; | |
345 | __le32 ref_count; | |
346 | } __packed; | |
347 | ||
348 | #define SMD_CHANNEL_FLAGS_EDGE_MASK 0xff | |
349 | #define SMD_CHANNEL_FLAGS_STREAM BIT(8) | |
350 | #define SMD_CHANNEL_FLAGS_PACKET BIT(9) | |
351 | ||
352 | /* | |
353 | * Each smd packet contains a 20 byte header, with the first 4 being the length | |
354 | * of the packet. | |
355 | */ | |
356 | #define SMD_PACKET_HEADER_LEN 20 | |
357 | ||
358 | /* | |
359 | * Signal the remote processor associated with 'channel'. | |
360 | */ | |
361 | static void qcom_smd_signal_channel(struct qcom_smd_channel *channel) | |
362 | { | |
363 | struct qcom_smd_edge *edge = channel->edge; | |
364 | ||
365 | regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit)); | |
366 | } | |
367 | ||
368 | /* | |
369 | * Initialize the tx channel info | |
370 | */ | |
371 | static void qcom_smd_channel_reset(struct qcom_smd_channel *channel) | |
372 | { | |
373 | SET_TX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); | |
374 | SET_TX_CHANNEL_FLAG(channel, fDSR, 0); | |
375 | SET_TX_CHANNEL_FLAG(channel, fCTS, 0); | |
376 | SET_TX_CHANNEL_FLAG(channel, fCD, 0); | |
377 | SET_TX_CHANNEL_FLAG(channel, fRI, 0); | |
378 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 0); | |
379 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); | |
380 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); | |
381 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); | |
382 | SET_TX_CHANNEL_INFO(channel, head, 0); | |
383 | SET_RX_CHANNEL_INFO(channel, tail, 0); | |
384 | ||
385 | qcom_smd_signal_channel(channel); | |
386 | ||
387 | channel->state = SMD_CHANNEL_CLOSED; | |
388 | channel->pkt_size = 0; | |
389 | } | |
390 | ||
391 | /* | |
392 | * Set the callback for a channel, with appropriate locking | |
393 | */ | |
394 | static void qcom_smd_channel_set_callback(struct qcom_smd_channel *channel, | |
395 | rpmsg_rx_cb_t cb) | |
396 | { | |
397 | struct rpmsg_endpoint *ept = &channel->qsept->ept; | |
398 | unsigned long flags; | |
399 | ||
400 | spin_lock_irqsave(&channel->recv_lock, flags); | |
401 | ept->cb = cb; | |
402 | spin_unlock_irqrestore(&channel->recv_lock, flags); | |
403 | }; | |
404 | ||
405 | /* | |
406 | * Calculate the amount of data available in the rx fifo | |
407 | */ | |
408 | static size_t qcom_smd_channel_get_rx_avail(struct qcom_smd_channel *channel) | |
409 | { | |
410 | unsigned head; | |
411 | unsigned tail; | |
412 | ||
413 | head = GET_RX_CHANNEL_INFO(channel, head); | |
414 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
415 | ||
416 | return (head - tail) & (channel->fifo_size - 1); | |
417 | } | |
418 | ||
419 | /* | |
420 | * Set tx channel state and inform the remote processor | |
421 | */ | |
422 | static void qcom_smd_channel_set_state(struct qcom_smd_channel *channel, | |
423 | int state) | |
424 | { | |
425 | struct qcom_smd_edge *edge = channel->edge; | |
426 | bool is_open = state == SMD_CHANNEL_OPENED; | |
427 | ||
428 | if (channel->state == state) | |
429 | return; | |
430 | ||
431 | dev_dbg(&edge->dev, "set_state(%s, %d)\n", channel->name, state); | |
432 | ||
433 | SET_TX_CHANNEL_FLAG(channel, fDSR, is_open); | |
434 | SET_TX_CHANNEL_FLAG(channel, fCTS, is_open); | |
435 | SET_TX_CHANNEL_FLAG(channel, fCD, is_open); | |
436 | ||
437 | SET_TX_CHANNEL_INFO(channel, state, state); | |
438 | SET_TX_CHANNEL_FLAG(channel, fSTATE, 1); | |
439 | ||
440 | channel->state = state; | |
441 | qcom_smd_signal_channel(channel); | |
442 | } | |
443 | ||
444 | /* | |
445 | * Copy count bytes of data using 32bit accesses, if that's required. | |
446 | */ | |
447 | static void smd_copy_to_fifo(void __iomem *dst, | |
448 | const void *src, | |
449 | size_t count, | |
450 | bool word_aligned) | |
451 | { | |
452 | if (word_aligned) { | |
453 | __iowrite32_copy(dst, src, count / sizeof(u32)); | |
454 | } else { | |
455 | memcpy_toio(dst, src, count); | |
456 | } | |
457 | } | |
458 | ||
459 | /* | |
460 | * Copy count bytes of data using 32bit accesses, if that is required. | |
461 | */ | |
462 | static void smd_copy_from_fifo(void *dst, | |
463 | const void __iomem *src, | |
464 | size_t count, | |
465 | bool word_aligned) | |
466 | { | |
467 | if (word_aligned) { | |
468 | __ioread32_copy(dst, src, count / sizeof(u32)); | |
469 | } else { | |
470 | memcpy_fromio(dst, src, count); | |
471 | } | |
472 | } | |
473 | ||
474 | /* | |
475 | * Read count bytes of data from the rx fifo into buf, but don't advance the | |
476 | * tail. | |
477 | */ | |
478 | static size_t qcom_smd_channel_peek(struct qcom_smd_channel *channel, | |
479 | void *buf, size_t count) | |
480 | { | |
481 | bool word_aligned; | |
482 | unsigned tail; | |
483 | size_t len; | |
484 | ||
485 | word_aligned = channel->info_word; | |
486 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
487 | ||
488 | len = min_t(size_t, count, channel->fifo_size - tail); | |
489 | if (len) { | |
490 | smd_copy_from_fifo(buf, | |
491 | channel->rx_fifo + tail, | |
492 | len, | |
493 | word_aligned); | |
494 | } | |
495 | ||
496 | if (len != count) { | |
497 | smd_copy_from_fifo(buf + len, | |
498 | channel->rx_fifo, | |
499 | count - len, | |
500 | word_aligned); | |
501 | } | |
502 | ||
503 | return count; | |
504 | } | |
505 | ||
506 | /* | |
507 | * Advance the rx tail by count bytes. | |
508 | */ | |
509 | static void qcom_smd_channel_advance(struct qcom_smd_channel *channel, | |
510 | size_t count) | |
511 | { | |
512 | unsigned tail; | |
513 | ||
514 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
515 | tail += count; | |
516 | tail &= (channel->fifo_size - 1); | |
517 | SET_RX_CHANNEL_INFO(channel, tail, tail); | |
518 | } | |
519 | ||
520 | /* | |
521 | * Read out a single packet from the rx fifo and deliver it to the device | |
522 | */ | |
523 | static int qcom_smd_channel_recv_single(struct qcom_smd_channel *channel) | |
524 | { | |
525 | struct rpmsg_endpoint *ept = &channel->qsept->ept; | |
526 | unsigned tail; | |
527 | size_t len; | |
528 | void *ptr; | |
529 | int ret; | |
530 | ||
531 | tail = GET_RX_CHANNEL_INFO(channel, tail); | |
532 | ||
533 | /* Use bounce buffer if the data wraps */ | |
534 | if (tail + channel->pkt_size >= channel->fifo_size) { | |
535 | ptr = channel->bounce_buffer; | |
536 | len = qcom_smd_channel_peek(channel, ptr, channel->pkt_size); | |
537 | } else { | |
538 | ptr = channel->rx_fifo + tail; | |
539 | len = channel->pkt_size; | |
540 | } | |
541 | ||
542 | ret = ept->cb(ept->rpdev, ptr, len, ept->priv, RPMSG_ADDR_ANY); | |
543 | if (ret < 0) | |
544 | return ret; | |
545 | ||
546 | /* Only forward the tail if the client consumed the data */ | |
547 | qcom_smd_channel_advance(channel, len); | |
548 | ||
549 | channel->pkt_size = 0; | |
550 | ||
551 | return 0; | |
552 | } | |
553 | ||
554 | /* | |
555 | * Per channel interrupt handling | |
556 | */ | |
557 | static bool qcom_smd_channel_intr(struct qcom_smd_channel *channel) | |
558 | { | |
559 | bool need_state_scan = false; | |
560 | int remote_state; | |
561 | __le32 pktlen; | |
562 | int avail; | |
563 | int ret; | |
564 | ||
565 | /* Handle state changes */ | |
566 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
567 | if (remote_state != channel->remote_state) { | |
568 | channel->remote_state = remote_state; | |
569 | need_state_scan = true; | |
570 | } | |
571 | /* Indicate that we have seen any state change */ | |
572 | SET_RX_CHANNEL_FLAG(channel, fSTATE, 0); | |
573 | ||
574 | /* Signal waiting qcom_smd_send() about the interrupt */ | |
575 | if (!GET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) | |
576 | wake_up_interruptible(&channel->fblockread_event); | |
577 | ||
578 | /* Don't consume any data until we've opened the channel */ | |
579 | if (channel->state != SMD_CHANNEL_OPENED) | |
580 | goto out; | |
581 | ||
582 | /* Indicate that we've seen the new data */ | |
583 | SET_RX_CHANNEL_FLAG(channel, fHEAD, 0); | |
584 | ||
585 | /* Consume data */ | |
586 | for (;;) { | |
587 | avail = qcom_smd_channel_get_rx_avail(channel); | |
588 | ||
589 | if (!channel->pkt_size && avail >= SMD_PACKET_HEADER_LEN) { | |
590 | qcom_smd_channel_peek(channel, &pktlen, sizeof(pktlen)); | |
591 | qcom_smd_channel_advance(channel, SMD_PACKET_HEADER_LEN); | |
592 | channel->pkt_size = le32_to_cpu(pktlen); | |
593 | } else if (channel->pkt_size && avail >= channel->pkt_size) { | |
594 | ret = qcom_smd_channel_recv_single(channel); | |
595 | if (ret) | |
596 | break; | |
597 | } else { | |
598 | break; | |
599 | } | |
600 | } | |
601 | ||
602 | /* Indicate that we have seen and updated tail */ | |
603 | SET_RX_CHANNEL_FLAG(channel, fTAIL, 1); | |
604 | ||
605 | /* Signal the remote that we've consumed the data (if requested) */ | |
606 | if (!GET_RX_CHANNEL_FLAG(channel, fBLOCKREADINTR)) { | |
607 | /* Ensure ordering of channel info updates */ | |
608 | wmb(); | |
609 | ||
610 | qcom_smd_signal_channel(channel); | |
611 | } | |
612 | ||
613 | out: | |
614 | return need_state_scan; | |
615 | } | |
616 | ||
617 | /* | |
618 | * The edge interrupts are triggered by the remote processor on state changes, | |
619 | * channel info updates or when new channels are created. | |
620 | */ | |
621 | static irqreturn_t qcom_smd_edge_intr(int irq, void *data) | |
622 | { | |
623 | struct qcom_smd_edge *edge = data; | |
624 | struct qcom_smd_channel *channel; | |
625 | unsigned available; | |
626 | bool kick_scanner = false; | |
627 | bool kick_state = false; | |
628 | ||
629 | /* | |
630 | * Handle state changes or data on each of the channels on this edge | |
631 | */ | |
632 | spin_lock(&edge->channels_lock); | |
633 | list_for_each_entry(channel, &edge->channels, list) { | |
634 | spin_lock(&channel->recv_lock); | |
635 | kick_state |= qcom_smd_channel_intr(channel); | |
636 | spin_unlock(&channel->recv_lock); | |
637 | } | |
638 | spin_unlock(&edge->channels_lock); | |
639 | ||
640 | /* | |
641 | * Creating a new channel requires allocating an smem entry, so we only | |
642 | * have to scan if the amount of available space in smem have changed | |
643 | * since last scan. | |
644 | */ | |
645 | available = qcom_smem_get_free_space(edge->remote_pid); | |
646 | if (available != edge->smem_available) { | |
647 | edge->smem_available = available; | |
648 | kick_scanner = true; | |
649 | } | |
650 | ||
651 | if (kick_scanner) | |
652 | schedule_work(&edge->scan_work); | |
653 | if (kick_state) | |
654 | schedule_work(&edge->state_work); | |
655 | ||
656 | return IRQ_HANDLED; | |
657 | } | |
658 | ||
659 | /* | |
660 | * Calculate how much space is available in the tx fifo. | |
661 | */ | |
662 | static size_t qcom_smd_get_tx_avail(struct qcom_smd_channel *channel) | |
663 | { | |
664 | unsigned head; | |
665 | unsigned tail; | |
666 | unsigned mask = channel->fifo_size - 1; | |
667 | ||
668 | head = GET_TX_CHANNEL_INFO(channel, head); | |
669 | tail = GET_TX_CHANNEL_INFO(channel, tail); | |
670 | ||
671 | return mask - ((head - tail) & mask); | |
672 | } | |
673 | ||
674 | /* | |
675 | * Write count bytes of data into channel, possibly wrapping in the ring buffer | |
676 | */ | |
677 | static int qcom_smd_write_fifo(struct qcom_smd_channel *channel, | |
678 | const void *data, | |
679 | size_t count) | |
680 | { | |
681 | bool word_aligned; | |
682 | unsigned head; | |
683 | size_t len; | |
684 | ||
685 | word_aligned = channel->info_word; | |
686 | head = GET_TX_CHANNEL_INFO(channel, head); | |
687 | ||
688 | len = min_t(size_t, count, channel->fifo_size - head); | |
689 | if (len) { | |
690 | smd_copy_to_fifo(channel->tx_fifo + head, | |
691 | data, | |
692 | len, | |
693 | word_aligned); | |
694 | } | |
695 | ||
696 | if (len != count) { | |
697 | smd_copy_to_fifo(channel->tx_fifo, | |
698 | data + len, | |
699 | count - len, | |
700 | word_aligned); | |
701 | } | |
702 | ||
703 | head += count; | |
704 | head &= (channel->fifo_size - 1); | |
705 | SET_TX_CHANNEL_INFO(channel, head, head); | |
706 | ||
707 | return count; | |
708 | } | |
709 | ||
710 | /** | |
711 | * qcom_smd_send - write data to smd channel | |
712 | * @channel: channel handle | |
713 | * @data: buffer of data to write | |
714 | * @len: number of bytes to write | |
715 | * | |
716 | * This is a blocking write of len bytes into the channel's tx ring buffer and | |
717 | * signal the remote end. It will sleep until there is enough space available | |
718 | * in the tx buffer, utilizing the fBLOCKREADINTR signaling mechanism to avoid | |
719 | * polling. | |
720 | */ | |
721 | static int __qcom_smd_send(struct qcom_smd_channel *channel, const void *data, | |
722 | int len, bool wait) | |
723 | { | |
724 | __le32 hdr[5] = { cpu_to_le32(len), }; | |
725 | int tlen = sizeof(hdr) + len; | |
726 | int ret; | |
727 | ||
728 | /* Word aligned channels only accept word size aligned data */ | |
729 | if (channel->info_word && len % 4) | |
730 | return -EINVAL; | |
731 | ||
732 | /* Reject packets that are too big */ | |
733 | if (tlen >= channel->fifo_size) | |
734 | return -EINVAL; | |
735 | ||
736 | ret = mutex_lock_interruptible(&channel->tx_lock); | |
737 | if (ret) | |
738 | return ret; | |
739 | ||
740 | while (qcom_smd_get_tx_avail(channel) < tlen) { | |
741 | if (!wait) { | |
742 | ret = -ENOMEM; | |
743 | goto out; | |
744 | } | |
745 | ||
746 | if (channel->state != SMD_CHANNEL_OPENED) { | |
747 | ret = -EPIPE; | |
748 | goto out; | |
749 | } | |
750 | ||
751 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 0); | |
752 | ||
753 | ret = wait_event_interruptible(channel->fblockread_event, | |
754 | qcom_smd_get_tx_avail(channel) >= tlen || | |
755 | channel->state != SMD_CHANNEL_OPENED); | |
756 | if (ret) | |
757 | goto out; | |
758 | ||
759 | SET_TX_CHANNEL_FLAG(channel, fBLOCKREADINTR, 1); | |
760 | } | |
761 | ||
762 | SET_TX_CHANNEL_FLAG(channel, fTAIL, 0); | |
763 | ||
764 | qcom_smd_write_fifo(channel, hdr, sizeof(hdr)); | |
765 | qcom_smd_write_fifo(channel, data, len); | |
766 | ||
767 | SET_TX_CHANNEL_FLAG(channel, fHEAD, 1); | |
768 | ||
769 | /* Ensure ordering of channel info updates */ | |
770 | wmb(); | |
771 | ||
772 | qcom_smd_signal_channel(channel); | |
773 | ||
774 | out: | |
775 | mutex_unlock(&channel->tx_lock); | |
776 | ||
777 | return ret; | |
778 | } | |
779 | ||
780 | /* | |
781 | * Helper for opening a channel | |
782 | */ | |
783 | static int qcom_smd_channel_open(struct qcom_smd_channel *channel, | |
784 | rpmsg_rx_cb_t cb) | |
785 | { | |
786 | size_t bb_size; | |
787 | ||
788 | /* | |
789 | * Packets are maximum 4k, but reduce if the fifo is smaller | |
790 | */ | |
791 | bb_size = min(channel->fifo_size, SZ_4K); | |
792 | channel->bounce_buffer = kmalloc(bb_size, GFP_KERNEL); | |
793 | if (!channel->bounce_buffer) | |
794 | return -ENOMEM; | |
795 | ||
796 | qcom_smd_channel_set_callback(channel, cb); | |
797 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENING); | |
798 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_OPENED); | |
799 | ||
800 | return 0; | |
801 | } | |
802 | ||
803 | /* | |
804 | * Helper for closing and resetting a channel | |
805 | */ | |
806 | static void qcom_smd_channel_close(struct qcom_smd_channel *channel) | |
807 | { | |
808 | qcom_smd_channel_set_callback(channel, NULL); | |
809 | ||
810 | kfree(channel->bounce_buffer); | |
811 | channel->bounce_buffer = NULL; | |
812 | ||
813 | qcom_smd_channel_set_state(channel, SMD_CHANNEL_CLOSED); | |
814 | qcom_smd_channel_reset(channel); | |
815 | } | |
816 | ||
817 | static struct qcom_smd_channel * | |
818 | qcom_smd_find_channel(struct qcom_smd_edge *edge, const char *name) | |
819 | { | |
820 | struct qcom_smd_channel *channel; | |
821 | struct qcom_smd_channel *ret = NULL; | |
822 | unsigned long flags; | |
823 | unsigned state; | |
824 | ||
825 | spin_lock_irqsave(&edge->channels_lock, flags); | |
826 | list_for_each_entry(channel, &edge->channels, list) { | |
827 | if (strcmp(channel->name, name)) | |
828 | continue; | |
829 | ||
830 | state = GET_RX_CHANNEL_INFO(channel, state); | |
831 | if (state != SMD_CHANNEL_OPENING && | |
832 | state != SMD_CHANNEL_OPENED) | |
833 | continue; | |
834 | ||
835 | ret = channel; | |
836 | break; | |
837 | } | |
838 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
839 | ||
840 | return ret; | |
841 | } | |
842 | ||
843 | static void __ept_release(struct kref *kref) | |
844 | { | |
845 | struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, | |
846 | refcount); | |
847 | kfree(to_smd_endpoint(ept)); | |
848 | } | |
849 | ||
850 | static struct rpmsg_endpoint *qcom_smd_create_ept(struct rpmsg_device *rpdev, | |
851 | rpmsg_rx_cb_t cb, void *priv, | |
852 | struct rpmsg_channel_info chinfo) | |
853 | { | |
854 | struct qcom_smd_endpoint *qsept; | |
855 | struct qcom_smd_channel *channel; | |
856 | struct qcom_smd_device *qsdev = to_smd_device(rpdev); | |
857 | struct qcom_smd_edge *edge = qsdev->edge; | |
858 | struct rpmsg_endpoint *ept; | |
859 | const char *name = chinfo.name; | |
860 | int ret; | |
861 | ||
862 | /* Wait up to HZ for the channel to appear */ | |
863 | ret = wait_event_interruptible_timeout(edge->new_channel_event, | |
864 | (channel = qcom_smd_find_channel(edge, name)) != NULL, | |
865 | HZ); | |
866 | if (!ret) | |
867 | return NULL; | |
868 | ||
869 | if (channel->state != SMD_CHANNEL_CLOSED) { | |
870 | dev_err(&rpdev->dev, "channel %s is busy\n", channel->name); | |
871 | return NULL; | |
872 | } | |
873 | ||
874 | qsept = kzalloc(sizeof(*qsept), GFP_KERNEL); | |
875 | if (!qsept) | |
876 | return NULL; | |
877 | ||
878 | ept = &qsept->ept; | |
879 | ||
880 | kref_init(&ept->refcount); | |
881 | ||
882 | ept->rpdev = rpdev; | |
883 | ept->cb = cb; | |
884 | ept->priv = priv; | |
885 | ept->ops = &qcom_smd_endpoint_ops; | |
886 | ||
887 | channel->qsept = qsept; | |
888 | qsept->qsch = channel; | |
889 | ||
890 | ret = qcom_smd_channel_open(channel, cb); | |
891 | if (ret) | |
892 | goto free_ept; | |
893 | ||
894 | return ept; | |
895 | ||
896 | free_ept: | |
897 | channel->qsept = NULL; | |
898 | kref_put(&ept->refcount, __ept_release); | |
899 | return NULL; | |
900 | } | |
901 | ||
902 | static void qcom_smd_destroy_ept(struct rpmsg_endpoint *ept) | |
903 | { | |
904 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
905 | struct qcom_smd_channel *ch = qsept->qsch; | |
906 | ||
907 | qcom_smd_channel_close(ch); | |
908 | ch->qsept = NULL; | |
909 | kref_put(&ept->refcount, __ept_release); | |
910 | } | |
911 | ||
912 | static int qcom_smd_send(struct rpmsg_endpoint *ept, void *data, int len) | |
913 | { | |
914 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
915 | ||
916 | return __qcom_smd_send(qsept->qsch, data, len, true); | |
917 | } | |
918 | ||
919 | static int qcom_smd_trysend(struct rpmsg_endpoint *ept, void *data, int len) | |
920 | { | |
921 | struct qcom_smd_endpoint *qsept = to_smd_endpoint(ept); | |
922 | ||
923 | return __qcom_smd_send(qsept->qsch, data, len, false); | |
924 | } | |
925 | ||
926 | /* | |
927 | * Finds the device_node for the smd child interested in this channel. | |
928 | */ | |
929 | static struct device_node *qcom_smd_match_channel(struct device_node *edge_node, | |
930 | const char *channel) | |
931 | { | |
932 | struct device_node *child; | |
933 | const char *name; | |
934 | const char *key; | |
935 | int ret; | |
936 | ||
937 | for_each_available_child_of_node(edge_node, child) { | |
938 | key = "qcom,smd-channels"; | |
939 | ret = of_property_read_string(child, key, &name); | |
940 | if (ret) | |
941 | continue; | |
942 | ||
943 | if (strcmp(name, channel) == 0) | |
944 | return child; | |
945 | } | |
946 | ||
947 | return NULL; | |
948 | } | |
949 | ||
950 | static const struct rpmsg_device_ops qcom_smd_device_ops = { | |
951 | .create_ept = qcom_smd_create_ept, | |
952 | }; | |
953 | ||
954 | static const struct rpmsg_endpoint_ops qcom_smd_endpoint_ops = { | |
955 | .destroy_ept = qcom_smd_destroy_ept, | |
956 | .send = qcom_smd_send, | |
957 | .trysend = qcom_smd_trysend, | |
958 | }; | |
959 | ||
960 | /* | |
961 | * Create a smd client device for channel that is being opened. | |
962 | */ | |
963 | static int qcom_smd_create_device(struct qcom_smd_channel *channel) | |
964 | { | |
965 | struct qcom_smd_device *qsdev; | |
966 | struct rpmsg_device *rpdev; | |
967 | struct qcom_smd_edge *edge = channel->edge; | |
968 | ||
969 | dev_dbg(&edge->dev, "registering '%s'\n", channel->name); | |
970 | ||
971 | qsdev = kzalloc(sizeof(*qsdev), GFP_KERNEL); | |
972 | if (!qsdev) | |
973 | return -ENOMEM; | |
974 | ||
975 | /* Link qsdev to our SMD edge */ | |
976 | qsdev->edge = edge; | |
977 | ||
978 | /* Assign callbacks for rpmsg_device */ | |
979 | qsdev->rpdev.ops = &qcom_smd_device_ops; | |
980 | ||
981 | /* Assign public information to the rpmsg_device */ | |
982 | rpdev = &qsdev->rpdev; | |
983 | strncpy(rpdev->id.name, channel->name, RPMSG_NAME_SIZE); | |
984 | rpdev->src = RPMSG_ADDR_ANY; | |
985 | rpdev->dst = RPMSG_ADDR_ANY; | |
986 | ||
987 | rpdev->dev.of_node = qcom_smd_match_channel(edge->of_node, channel->name); | |
988 | rpdev->dev.parent = &edge->dev; | |
989 | ||
990 | return rpmsg_register_device(rpdev); | |
991 | } | |
992 | ||
993 | /* | |
994 | * Allocate the qcom_smd_channel object for a newly found smd channel, | |
995 | * retrieving and validating the smem items involved. | |
996 | */ | |
997 | static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *edge, | |
998 | unsigned smem_info_item, | |
999 | unsigned smem_fifo_item, | |
1000 | char *name) | |
1001 | { | |
1002 | struct qcom_smd_channel *channel; | |
1003 | size_t fifo_size; | |
1004 | size_t info_size; | |
1005 | void *fifo_base; | |
1006 | void *info; | |
1007 | int ret; | |
1008 | ||
1009 | channel = devm_kzalloc(&edge->dev, sizeof(*channel), GFP_KERNEL); | |
1010 | if (!channel) | |
1011 | return ERR_PTR(-ENOMEM); | |
1012 | ||
1013 | channel->edge = edge; | |
1014 | channel->name = devm_kstrdup(&edge->dev, name, GFP_KERNEL); | |
1015 | if (!channel->name) | |
1016 | return ERR_PTR(-ENOMEM); | |
1017 | ||
1018 | mutex_init(&channel->tx_lock); | |
1019 | spin_lock_init(&channel->recv_lock); | |
1020 | init_waitqueue_head(&channel->fblockread_event); | |
1021 | ||
1022 | info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size); | |
1023 | if (IS_ERR(info)) { | |
1024 | ret = PTR_ERR(info); | |
1025 | goto free_name_and_channel; | |
1026 | } | |
1027 | ||
1028 | /* | |
1029 | * Use the size of the item to figure out which channel info struct to | |
1030 | * use. | |
1031 | */ | |
1032 | if (info_size == 2 * sizeof(struct smd_channel_info_word)) { | |
1033 | channel->info_word = info; | |
1034 | } else if (info_size == 2 * sizeof(struct smd_channel_info)) { | |
1035 | channel->info = info; | |
1036 | } else { | |
1037 | dev_err(&edge->dev, | |
1038 | "channel info of size %zu not supported\n", info_size); | |
1039 | ret = -EINVAL; | |
1040 | goto free_name_and_channel; | |
1041 | } | |
1042 | ||
1043 | fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size); | |
1044 | if (IS_ERR(fifo_base)) { | |
1045 | ret = PTR_ERR(fifo_base); | |
1046 | goto free_name_and_channel; | |
1047 | } | |
1048 | ||
1049 | /* The channel consist of a rx and tx fifo of equal size */ | |
1050 | fifo_size /= 2; | |
1051 | ||
1052 | dev_dbg(&edge->dev, "new channel '%s' info-size: %zu fifo-size: %zu\n", | |
1053 | name, info_size, fifo_size); | |
1054 | ||
1055 | channel->tx_fifo = fifo_base; | |
1056 | channel->rx_fifo = fifo_base + fifo_size; | |
1057 | channel->fifo_size = fifo_size; | |
1058 | ||
1059 | qcom_smd_channel_reset(channel); | |
1060 | ||
1061 | return channel; | |
1062 | ||
1063 | free_name_and_channel: | |
1064 | devm_kfree(&edge->dev, channel->name); | |
1065 | devm_kfree(&edge->dev, channel); | |
1066 | ||
1067 | return ERR_PTR(ret); | |
1068 | } | |
1069 | ||
1070 | /* | |
1071 | * Scans the allocation table for any newly allocated channels, calls | |
1072 | * qcom_smd_create_channel() to create representations of these and add | |
1073 | * them to the edge's list of channels. | |
1074 | */ | |
1075 | static void qcom_channel_scan_worker(struct work_struct *work) | |
1076 | { | |
1077 | struct qcom_smd_edge *edge = container_of(work, struct qcom_smd_edge, scan_work); | |
1078 | struct qcom_smd_alloc_entry *alloc_tbl; | |
1079 | struct qcom_smd_alloc_entry *entry; | |
1080 | struct qcom_smd_channel *channel; | |
1081 | unsigned long flags; | |
1082 | unsigned fifo_id; | |
1083 | unsigned info_id; | |
1084 | int tbl; | |
1085 | int i; | |
1086 | u32 eflags, cid; | |
1087 | ||
1088 | for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) { | |
1089 | alloc_tbl = qcom_smem_get(edge->remote_pid, | |
1090 | smem_items[tbl].alloc_tbl_id, NULL); | |
1091 | if (IS_ERR(alloc_tbl)) | |
1092 | continue; | |
1093 | ||
1094 | for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) { | |
1095 | entry = &alloc_tbl[i]; | |
1096 | eflags = le32_to_cpu(entry->flags); | |
1097 | if (test_bit(i, edge->allocated[tbl])) | |
1098 | continue; | |
1099 | ||
1100 | if (entry->ref_count == 0) | |
1101 | continue; | |
1102 | ||
1103 | if (!entry->name[0]) | |
1104 | continue; | |
1105 | ||
1106 | if (!(eflags & SMD_CHANNEL_FLAGS_PACKET)) | |
1107 | continue; | |
1108 | ||
1109 | if ((eflags & SMD_CHANNEL_FLAGS_EDGE_MASK) != edge->edge_id) | |
1110 | continue; | |
1111 | ||
1112 | cid = le32_to_cpu(entry->cid); | |
1113 | info_id = smem_items[tbl].info_base_id + cid; | |
1114 | fifo_id = smem_items[tbl].fifo_base_id + cid; | |
1115 | ||
1116 | channel = qcom_smd_create_channel(edge, info_id, fifo_id, entry->name); | |
1117 | if (IS_ERR(channel)) | |
1118 | continue; | |
1119 | ||
1120 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1121 | list_add(&channel->list, &edge->channels); | |
1122 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1123 | ||
1124 | dev_dbg(&edge->dev, "new channel found: '%s'\n", channel->name); | |
1125 | set_bit(i, edge->allocated[tbl]); | |
1126 | ||
1127 | wake_up_interruptible(&edge->new_channel_event); | |
1128 | } | |
1129 | } | |
1130 | ||
1131 | schedule_work(&edge->state_work); | |
1132 | } | |
1133 | ||
1134 | /* | |
1135 | * This per edge worker scans smem for any new channels and register these. It | |
1136 | * then scans all registered channels for state changes that should be handled | |
1137 | * by creating or destroying smd client devices for the registered channels. | |
1138 | * | |
1139 | * LOCKING: edge->channels_lock only needs to cover the list operations, as the | |
1140 | * worker is killed before any channels are deallocated | |
1141 | */ | |
1142 | static void qcom_channel_state_worker(struct work_struct *work) | |
1143 | { | |
1144 | struct qcom_smd_channel *channel; | |
1145 | struct qcom_smd_edge *edge = container_of(work, | |
1146 | struct qcom_smd_edge, | |
1147 | state_work); | |
1148 | struct rpmsg_channel_info chinfo; | |
1149 | unsigned remote_state; | |
1150 | unsigned long flags; | |
1151 | ||
1152 | /* | |
1153 | * Register a device for any closed channel where the remote processor | |
1154 | * is showing interest in opening the channel. | |
1155 | */ | |
1156 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1157 | list_for_each_entry(channel, &edge->channels, list) { | |
1158 | if (channel->state != SMD_CHANNEL_CLOSED) | |
1159 | continue; | |
1160 | ||
1161 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1162 | if (remote_state != SMD_CHANNEL_OPENING && | |
1163 | remote_state != SMD_CHANNEL_OPENED) | |
1164 | continue; | |
1165 | ||
1166 | if (channel->registered) | |
1167 | continue; | |
1168 | ||
1169 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1170 | qcom_smd_create_device(channel); | |
1171 | channel->registered = true; | |
1172 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1173 | ||
1174 | channel->registered = true; | |
1175 | } | |
1176 | ||
1177 | /* | |
1178 | * Unregister the device for any channel that is opened where the | |
1179 | * remote processor is closing the channel. | |
1180 | */ | |
1181 | list_for_each_entry(channel, &edge->channels, list) { | |
1182 | if (channel->state != SMD_CHANNEL_OPENING && | |
1183 | channel->state != SMD_CHANNEL_OPENED) | |
1184 | continue; | |
1185 | ||
1186 | remote_state = GET_RX_CHANNEL_INFO(channel, state); | |
1187 | if (remote_state == SMD_CHANNEL_OPENING || | |
1188 | remote_state == SMD_CHANNEL_OPENED) | |
1189 | continue; | |
1190 | ||
1191 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1192 | ||
1193 | strncpy(chinfo.name, channel->name, sizeof(chinfo.name)); | |
1194 | chinfo.src = RPMSG_ADDR_ANY; | |
1195 | chinfo.dst = RPMSG_ADDR_ANY; | |
1196 | rpmsg_unregister_device(&edge->dev, &chinfo); | |
1197 | channel->registered = false; | |
1198 | spin_lock_irqsave(&edge->channels_lock, flags); | |
1199 | } | |
1200 | spin_unlock_irqrestore(&edge->channels_lock, flags); | |
1201 | } | |
1202 | ||
1203 | /* | |
1204 | * Parses an of_node describing an edge. | |
1205 | */ | |
1206 | static int qcom_smd_parse_edge(struct device *dev, | |
1207 | struct device_node *node, | |
1208 | struct qcom_smd_edge *edge) | |
1209 | { | |
1210 | struct device_node *syscon_np; | |
1211 | const char *key; | |
1212 | int irq; | |
1213 | int ret; | |
1214 | ||
1215 | INIT_LIST_HEAD(&edge->channels); | |
1216 | spin_lock_init(&edge->channels_lock); | |
1217 | ||
1218 | INIT_WORK(&edge->scan_work, qcom_channel_scan_worker); | |
1219 | INIT_WORK(&edge->state_work, qcom_channel_state_worker); | |
1220 | ||
1221 | edge->of_node = of_node_get(node); | |
1222 | ||
1223 | key = "qcom,smd-edge"; | |
1224 | ret = of_property_read_u32(node, key, &edge->edge_id); | |
1225 | if (ret) { | |
1226 | dev_err(dev, "edge missing %s property\n", key); | |
1227 | return -EINVAL; | |
1228 | } | |
1229 | ||
1230 | edge->remote_pid = QCOM_SMEM_HOST_ANY; | |
1231 | key = "qcom,remote-pid"; | |
1232 | of_property_read_u32(node, key, &edge->remote_pid); | |
1233 | ||
1234 | syscon_np = of_parse_phandle(node, "qcom,ipc", 0); | |
1235 | if (!syscon_np) { | |
1236 | dev_err(dev, "no qcom,ipc node\n"); | |
1237 | return -ENODEV; | |
1238 | } | |
1239 | ||
1240 | edge->ipc_regmap = syscon_node_to_regmap(syscon_np); | |
1241 | if (IS_ERR(edge->ipc_regmap)) | |
1242 | return PTR_ERR(edge->ipc_regmap); | |
1243 | ||
1244 | key = "qcom,ipc"; | |
1245 | ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset); | |
1246 | if (ret < 0) { | |
1247 | dev_err(dev, "no offset in %s\n", key); | |
1248 | return -EINVAL; | |
1249 | } | |
1250 | ||
1251 | ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit); | |
1252 | if (ret < 0) { | |
1253 | dev_err(dev, "no bit in %s\n", key); | |
1254 | return -EINVAL; | |
1255 | } | |
1256 | ||
1257 | irq = irq_of_parse_and_map(node, 0); | |
1258 | if (irq < 0) { | |
1259 | dev_err(dev, "required smd interrupt missing\n"); | |
1260 | return -EINVAL; | |
1261 | } | |
1262 | ||
1263 | ret = devm_request_irq(dev, irq, | |
1264 | qcom_smd_edge_intr, IRQF_TRIGGER_RISING, | |
1265 | node->name, edge); | |
1266 | if (ret) { | |
1267 | dev_err(dev, "failed to request smd irq\n"); | |
1268 | return ret; | |
1269 | } | |
1270 | ||
1271 | edge->irq = irq; | |
1272 | ||
1273 | return 0; | |
1274 | } | |
1275 | ||
1276 | /* | |
1277 | * Release function for an edge. | |
1278 | * Reset the state of each associated channel and free the edge context. | |
1279 | */ | |
1280 | static void qcom_smd_edge_release(struct device *dev) | |
1281 | { | |
1282 | struct qcom_smd_channel *channel; | |
1283 | struct qcom_smd_edge *edge = to_smd_edge(dev); | |
1284 | ||
1285 | list_for_each_entry(channel, &edge->channels, list) { | |
1286 | SET_RX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED); | |
1287 | SET_RX_CHANNEL_INFO(channel, head, 0); | |
1288 | SET_RX_CHANNEL_INFO(channel, tail, 0); | |
1289 | } | |
1290 | ||
1291 | kfree(edge); | |
1292 | } | |
1293 | ||
1294 | /** | |
1295 | * qcom_smd_register_edge() - register an edge based on an device_node | |
1296 | * @parent: parent device for the edge | |
1297 | * @node: device_node describing the edge | |
1298 | * | |
1299 | * Returns an edge reference, or negative ERR_PTR() on failure. | |
1300 | */ | |
1301 | struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent, | |
1302 | struct device_node *node) | |
1303 | { | |
1304 | struct qcom_smd_edge *edge; | |
1305 | int ret; | |
1306 | ||
1307 | edge = kzalloc(sizeof(*edge), GFP_KERNEL); | |
1308 | if (!edge) | |
1309 | return ERR_PTR(-ENOMEM); | |
1310 | ||
1311 | init_waitqueue_head(&edge->new_channel_event); | |
1312 | ||
1313 | edge->dev.parent = parent; | |
1314 | edge->dev.release = qcom_smd_edge_release; | |
1315 | dev_set_name(&edge->dev, "%s:%s", dev_name(parent), node->name); | |
1316 | ret = device_register(&edge->dev); | |
1317 | if (ret) { | |
1318 | pr_err("failed to register smd edge\n"); | |
1319 | return ERR_PTR(ret); | |
1320 | } | |
1321 | ||
1322 | ret = qcom_smd_parse_edge(&edge->dev, node, edge); | |
1323 | if (ret) { | |
1324 | dev_err(&edge->dev, "failed to parse smd edge\n"); | |
1325 | goto unregister_dev; | |
1326 | } | |
1327 | ||
1328 | schedule_work(&edge->scan_work); | |
1329 | ||
1330 | return edge; | |
1331 | ||
1332 | unregister_dev: | |
1333 | put_device(&edge->dev); | |
1334 | return ERR_PTR(ret); | |
1335 | } | |
1336 | EXPORT_SYMBOL(qcom_smd_register_edge); | |
1337 | ||
1338 | static int qcom_smd_remove_device(struct device *dev, void *data) | |
1339 | { | |
1340 | device_unregister(dev); | |
1341 | ||
1342 | return 0; | |
1343 | } | |
1344 | ||
1345 | /** | |
1346 | * qcom_smd_unregister_edge() - release an edge and its children | |
1347 | * @edge: edge reference acquired from qcom_smd_register_edge | |
1348 | */ | |
1349 | int qcom_smd_unregister_edge(struct qcom_smd_edge *edge) | |
1350 | { | |
1351 | int ret; | |
1352 | ||
1353 | disable_irq(edge->irq); | |
1354 | cancel_work_sync(&edge->scan_work); | |
1355 | cancel_work_sync(&edge->state_work); | |
1356 | ||
1357 | ret = device_for_each_child(&edge->dev, NULL, qcom_smd_remove_device); | |
1358 | if (ret) | |
1359 | dev_warn(&edge->dev, "can't remove smd device: %d\n", ret); | |
1360 | ||
1361 | device_unregister(&edge->dev); | |
1362 | ||
1363 | return 0; | |
1364 | } | |
1365 | EXPORT_SYMBOL(qcom_smd_unregister_edge); | |
1366 | ||
1367 | static int qcom_smd_probe(struct platform_device *pdev) | |
1368 | { | |
1369 | struct device_node *node; | |
1370 | void *p; | |
1371 | ||
1372 | /* Wait for smem */ | |
1373 | p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL); | |
1374 | if (PTR_ERR(p) == -EPROBE_DEFER) | |
1375 | return PTR_ERR(p); | |
1376 | ||
1377 | for_each_available_child_of_node(pdev->dev.of_node, node) | |
1378 | qcom_smd_register_edge(&pdev->dev, node); | |
1379 | ||
1380 | return 0; | |
1381 | } | |
1382 | ||
1383 | static int qcom_smd_remove_edge(struct device *dev, void *data) | |
1384 | { | |
1385 | struct qcom_smd_edge *edge = to_smd_edge(dev); | |
1386 | ||
1387 | return qcom_smd_unregister_edge(edge); | |
1388 | } | |
1389 | ||
1390 | /* | |
1391 | * Shut down all smd clients by making sure that each edge stops processing | |
1392 | * events and scanning for new channels, then call destroy on the devices. | |
1393 | */ | |
1394 | static int qcom_smd_remove(struct platform_device *pdev) | |
1395 | { | |
1396 | int ret; | |
1397 | ||
1398 | ret = device_for_each_child(&pdev->dev, NULL, qcom_smd_remove_edge); | |
1399 | if (ret) | |
1400 | dev_warn(&pdev->dev, "can't remove smd device: %d\n", ret); | |
1401 | ||
1402 | return ret; | |
1403 | } | |
1404 | ||
1405 | static const struct of_device_id qcom_smd_of_match[] = { | |
1406 | { .compatible = "qcom,smd" }, | |
1407 | {} | |
1408 | }; | |
1409 | MODULE_DEVICE_TABLE(of, qcom_smd_of_match); | |
1410 | ||
1411 | static struct platform_driver qcom_smd_driver = { | |
1412 | .probe = qcom_smd_probe, | |
1413 | .remove = qcom_smd_remove, | |
1414 | .driver = { | |
1415 | .name = "qcom-smd", | |
1416 | .of_match_table = qcom_smd_of_match, | |
1417 | }, | |
1418 | }; | |
1419 | ||
1420 | static int __init qcom_smd_init(void) | |
1421 | { | |
1422 | return platform_driver_register(&qcom_smd_driver); | |
1423 | } | |
1424 | subsys_initcall(qcom_smd_init); | |
1425 | ||
1426 | static void __exit qcom_smd_exit(void) | |
1427 | { | |
1428 | platform_driver_unregister(&qcom_smd_driver); | |
1429 | } | |
1430 | module_exit(qcom_smd_exit); | |
1431 | ||
1432 | MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>"); | |
1433 | MODULE_DESCRIPTION("Qualcomm Shared Memory Driver"); | |
1434 | MODULE_LICENSE("GPL v2"); |