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aa4f886f SH |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * System Control and Management Interface (SCMI) Message Protocol driver | |
4 | * | |
5 | * SCMI Message Protocol is used between the System Control Processor(SCP) | |
6 | * and the Application Processors(AP). The Message Handling Unit(MHU) | |
7 | * provides a mechanism for inter-processor communication between SCP's | |
8 | * Cortex M3 and AP. | |
9 | * | |
10 | * SCP offers control and management of the core/cluster power states, | |
11 | * various power domain DVFS including the core/cluster, certain system | |
12 | * clocks configuration, thermal sensors and many others. | |
13 | * | |
14 | * Copyright (C) 2018 ARM Ltd. | |
15 | */ | |
16 | ||
17 | #include <linux/bitmap.h> | |
18 | #include <linux/export.h> | |
19 | #include <linux/io.h> | |
20 | #include <linux/kernel.h> | |
d4c3751a | 21 | #include <linux/ktime.h> |
aa4f886f SH |
22 | #include <linux/module.h> |
23 | #include <linux/of_address.h> | |
24 | #include <linux/of_device.h> | |
d4c3751a | 25 | #include <linux/processor.h> |
aa4f886f SH |
26 | #include <linux/slab.h> |
27 | ||
28 | #include "common.h" | |
29 | ||
729d3530 LL |
30 | #define CREATE_TRACE_POINTS |
31 | #include <trace/events/scmi.h> | |
32 | ||
aa4f886f SH |
33 | enum scmi_error_codes { |
34 | SCMI_SUCCESS = 0, /* Success */ | |
35 | SCMI_ERR_SUPPORT = -1, /* Not supported */ | |
36 | SCMI_ERR_PARAMS = -2, /* Invalid Parameters */ | |
37 | SCMI_ERR_ACCESS = -3, /* Invalid access/permission denied */ | |
38 | SCMI_ERR_ENTRY = -4, /* Not found */ | |
39 | SCMI_ERR_RANGE = -5, /* Value out of range */ | |
40 | SCMI_ERR_BUSY = -6, /* Device busy */ | |
41 | SCMI_ERR_COMMS = -7, /* Communication Error */ | |
42 | SCMI_ERR_GENERIC = -8, /* Generic Error */ | |
43 | SCMI_ERR_HARDWARE = -9, /* Hardware Error */ | |
44 | SCMI_ERR_PROTOCOL = -10,/* Protocol Error */ | |
45 | SCMI_ERR_MAX | |
46 | }; | |
47 | ||
1baf47c2 | 48 | /* List of all SCMI devices active in system */ |
aa4f886f SH |
49 | static LIST_HEAD(scmi_list); |
50 | /* Protection for the entire list */ | |
51 | static DEFINE_MUTEX(scmi_list_mutex); | |
729d3530 LL |
52 | /* Track the unique id for the transfers for debug & profiling purpose */ |
53 | static atomic_t transfer_last_id; | |
aa4f886f SH |
54 | |
55 | /** | |
56 | * struct scmi_xfers_info - Structure to manage transfer information | |
57 | * | |
58 | * @xfer_block: Preallocated Message array | |
59 | * @xfer_alloc_table: Bitmap table for allocated messages. | |
60 | * Index of this bitmap table is also used for message | |
61 | * sequence identifier. | |
62 | * @xfer_lock: Protection for message allocation | |
63 | */ | |
64 | struct scmi_xfers_info { | |
65 | struct scmi_xfer *xfer_block; | |
66 | unsigned long *xfer_alloc_table; | |
aa4f886f SH |
67 | spinlock_t xfer_lock; |
68 | }; | |
69 | ||
aa4f886f | 70 | /** |
1baf47c2 | 71 | * struct scmi_info - Structure representing a SCMI instance |
aa4f886f SH |
72 | * |
73 | * @dev: Device pointer | |
74 | * @desc: SoC description for this instance | |
b6f20ff8 SH |
75 | * @version: SCMI revision information containing protocol version, |
76 | * implementation version and (sub-)vendor identification. | |
71af05a7 | 77 | * @handle: Instance of SCMI handle to send to clients |
38c927fb | 78 | * @tx_minfo: Universal Transmit Message management info |
4ebd8f6d | 79 | * @rx_minfo: Universal Receive Message management info |
3748daf7 | 80 | * @tx_idr: IDR object to map protocol id to Tx channel info pointer |
46cc7c28 | 81 | * @rx_idr: IDR object to map protocol id to Rx channel info pointer |
1baf47c2 | 82 | * @protocols_imp: List of protocols implemented, currently maximum of |
b6f20ff8 | 83 | * MAX_PROTOCOLS_IMP elements allocated by the base protocol |
1baf47c2 | 84 | * @node: List head |
aa4f886f SH |
85 | * @users: Number of users of this instance |
86 | */ | |
87 | struct scmi_info { | |
88 | struct device *dev; | |
89 | const struct scmi_desc *desc; | |
b6f20ff8 | 90 | struct scmi_revision_info version; |
aa4f886f | 91 | struct scmi_handle handle; |
38c927fb | 92 | struct scmi_xfers_info tx_minfo; |
4ebd8f6d | 93 | struct scmi_xfers_info rx_minfo; |
907b6d14 | 94 | struct idr tx_idr; |
46cc7c28 | 95 | struct idr rx_idr; |
b6f20ff8 | 96 | u8 *protocols_imp; |
aa4f886f SH |
97 | struct list_head node; |
98 | int users; | |
99 | }; | |
100 | ||
aa4f886f SH |
101 | #define handle_to_scmi_info(h) container_of(h, struct scmi_info, handle) |
102 | ||
aa4f886f SH |
103 | static const int scmi_linux_errmap[] = { |
104 | /* better than switch case as long as return value is continuous */ | |
105 | 0, /* SCMI_SUCCESS */ | |
106 | -EOPNOTSUPP, /* SCMI_ERR_SUPPORT */ | |
107 | -EINVAL, /* SCMI_ERR_PARAM */ | |
108 | -EACCES, /* SCMI_ERR_ACCESS */ | |
109 | -ENOENT, /* SCMI_ERR_ENTRY */ | |
110 | -ERANGE, /* SCMI_ERR_RANGE */ | |
111 | -EBUSY, /* SCMI_ERR_BUSY */ | |
112 | -ECOMM, /* SCMI_ERR_COMMS */ | |
113 | -EIO, /* SCMI_ERR_GENERIC */ | |
114 | -EREMOTEIO, /* SCMI_ERR_HARDWARE */ | |
115 | -EPROTO, /* SCMI_ERR_PROTOCOL */ | |
116 | }; | |
117 | ||
118 | static inline int scmi_to_linux_errno(int errno) | |
119 | { | |
120 | if (errno < SCMI_SUCCESS && errno > SCMI_ERR_MAX) | |
121 | return scmi_linux_errmap[-errno]; | |
122 | return -EIO; | |
123 | } | |
124 | ||
125 | /** | |
126 | * scmi_dump_header_dbg() - Helper to dump a message header. | |
127 | * | |
128 | * @dev: Device pointer corresponding to the SCMI entity | |
129 | * @hdr: pointer to header. | |
130 | */ | |
131 | static inline void scmi_dump_header_dbg(struct device *dev, | |
132 | struct scmi_msg_hdr *hdr) | |
133 | { | |
5b65af8f | 134 | dev_dbg(dev, "Message ID: %x Sequence ID: %x Protocol: %x\n", |
aa4f886f SH |
135 | hdr->id, hdr->seq, hdr->protocol_id); |
136 | } | |
137 | ||
aa4f886f | 138 | /** |
1baf47c2 | 139 | * scmi_xfer_get() - Allocate one message |
aa4f886f | 140 | * |
1baf47c2 | 141 | * @handle: Pointer to SCMI entity handle |
38c927fb | 142 | * @minfo: Pointer to Tx/Rx Message management info based on channel type |
aa4f886f | 143 | * |
5b65af8f | 144 | * Helper function which is used by various message functions that are |
aa4f886f SH |
145 | * exposed to clients of this driver for allocating a message traffic event. |
146 | * | |
147 | * This function can sleep depending on pending requests already in the system | |
148 | * for the SCMI entity. Further, this also holds a spinlock to maintain | |
149 | * integrity of internal data structures. | |
150 | * | |
151 | * Return: 0 if all went fine, else corresponding error. | |
152 | */ | |
38c927fb SH |
153 | static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, |
154 | struct scmi_xfers_info *minfo) | |
aa4f886f SH |
155 | { |
156 | u16 xfer_id; | |
157 | struct scmi_xfer *xfer; | |
158 | unsigned long flags, bit_pos; | |
159 | struct scmi_info *info = handle_to_scmi_info(handle); | |
aa4f886f SH |
160 | |
161 | /* Keep the locked section as small as possible */ | |
162 | spin_lock_irqsave(&minfo->xfer_lock, flags); | |
163 | bit_pos = find_first_zero_bit(minfo->xfer_alloc_table, | |
164 | info->desc->max_msg); | |
165 | if (bit_pos == info->desc->max_msg) { | |
166 | spin_unlock_irqrestore(&minfo->xfer_lock, flags); | |
167 | return ERR_PTR(-ENOMEM); | |
168 | } | |
169 | set_bit(bit_pos, minfo->xfer_alloc_table); | |
170 | spin_unlock_irqrestore(&minfo->xfer_lock, flags); | |
171 | ||
172 | xfer_id = bit_pos; | |
173 | ||
174 | xfer = &minfo->xfer_block[xfer_id]; | |
175 | xfer->hdr.seq = xfer_id; | |
176 | reinit_completion(&xfer->done); | |
729d3530 | 177 | xfer->transfer_id = atomic_inc_return(&transfer_last_id); |
aa4f886f SH |
178 | |
179 | return xfer; | |
180 | } | |
181 | ||
182 | /** | |
38c927fb | 183 | * __scmi_xfer_put() - Release a message |
aa4f886f | 184 | * |
38c927fb | 185 | * @minfo: Pointer to Tx/Rx Message management info based on channel type |
1baf47c2 | 186 | * @xfer: message that was reserved by scmi_xfer_get |
aa4f886f SH |
187 | * |
188 | * This holds a spinlock to maintain integrity of internal data structures. | |
189 | */ | |
38c927fb SH |
190 | static void |
191 | __scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) | |
aa4f886f SH |
192 | { |
193 | unsigned long flags; | |
aa4f886f SH |
194 | |
195 | /* | |
196 | * Keep the locked section as small as possible | |
197 | * NOTE: we might escape with smp_mb and no lock here.. | |
198 | * but just be conservative and symmetric. | |
199 | */ | |
200 | spin_lock_irqsave(&minfo->xfer_lock, flags); | |
201 | clear_bit(xfer->hdr.seq, minfo->xfer_alloc_table); | |
202 | spin_unlock_irqrestore(&minfo->xfer_lock, flags); | |
203 | } | |
204 | ||
4d09852b | 205 | static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) |
2747a967 | 206 | { |
5c8a47a5 | 207 | struct scmi_xfer *xfer; |
4d09852b SH |
208 | struct device *dev = cinfo->dev; |
209 | struct scmi_info *info = handle_to_scmi_info(cinfo->handle); | |
210 | struct scmi_xfers_info *minfo = &info->rx_minfo; | |
211 | ||
212 | xfer = scmi_xfer_get(cinfo->handle, minfo); | |
213 | if (IS_ERR(xfer)) { | |
214 | dev_err(dev, "failed to get free message slot (%ld)\n", | |
215 | PTR_ERR(xfer)); | |
87dff4e6 | 216 | info->desc->ops->clear_channel(cinfo); |
4d09852b SH |
217 | return; |
218 | } | |
219 | ||
220 | unpack_scmi_header(msg_hdr, &xfer->hdr); | |
221 | scmi_dump_header_dbg(dev, &xfer->hdr); | |
222 | info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size, | |
223 | xfer); | |
224 | ||
225 | trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, | |
226 | xfer->hdr.protocol_id, xfer->hdr.seq, | |
227 | MSG_TYPE_NOTIFICATION); | |
58ecdf03 | 228 | |
4d09852b SH |
229 | __scmi_xfer_put(minfo, xfer); |
230 | ||
87dff4e6 | 231 | info->desc->ops->clear_channel(cinfo); |
4d09852b SH |
232 | } |
233 | ||
234 | static void scmi_handle_response(struct scmi_chan_info *cinfo, | |
235 | u16 xfer_id, u8 msg_type) | |
236 | { | |
237 | struct scmi_xfer *xfer; | |
238 | struct device *dev = cinfo->dev; | |
239 | struct scmi_info *info = handle_to_scmi_info(cinfo->handle); | |
240 | struct scmi_xfers_info *minfo = &info->tx_minfo; | |
2747a967 SH |
241 | |
242 | /* Are we even expecting this? */ | |
243 | if (!test_bit(xfer_id, minfo->xfer_alloc_table)) { | |
244 | dev_err(dev, "message for %d is not expected!\n", xfer_id); | |
b37f5cc8 | 245 | info->desc->ops->clear_channel(cinfo); |
2747a967 SH |
246 | return; |
247 | } | |
248 | ||
249 | xfer = &minfo->xfer_block[xfer_id]; | |
c5bceb98 CM |
250 | /* |
251 | * Even if a response was indeed expected on this slot at this point, | |
252 | * a buggy platform could wrongly reply feeding us an unexpected | |
253 | * delayed response we're not prepared to handle: bail-out safely | |
254 | * blaming firmware. | |
255 | */ | |
256 | if (unlikely(msg_type == MSG_TYPE_DELAYED_RESP && !xfer->async_done)) { | |
257 | dev_err(dev, | |
258 | "Delayed Response for %d not expected! Buggy F/W ?\n", | |
259 | xfer_id); | |
260 | info->desc->ops->clear_channel(cinfo); | |
261 | /* It was unexpected, so nobody will clear the xfer if not us */ | |
262 | __scmi_xfer_put(minfo, xfer); | |
263 | return; | |
264 | } | |
2747a967 SH |
265 | |
266 | scmi_dump_header_dbg(dev, &xfer->hdr); | |
267 | ||
5c8a47a5 | 268 | info->desc->ops->fetch_response(cinfo, xfer); |
58ecdf03 | 269 | |
729d3530 LL |
270 | trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, |
271 | xfer->hdr.protocol_id, xfer->hdr.seq, | |
272 | msg_type); | |
273 | ||
d04fb2b2 CM |
274 | if (msg_type == MSG_TYPE_DELAYED_RESP) { |
275 | info->desc->ops->clear_channel(cinfo); | |
58ecdf03 | 276 | complete(xfer->async_done); |
d04fb2b2 | 277 | } else { |
58ecdf03 | 278 | complete(&xfer->done); |
d04fb2b2 | 279 | } |
2747a967 SH |
280 | } |
281 | ||
4d09852b SH |
282 | /** |
283 | * scmi_rx_callback() - callback for receiving messages | |
284 | * | |
285 | * @cinfo: SCMI channel info | |
286 | * @msg_hdr: Message header | |
287 | * | |
288 | * Processes one received message to appropriate transfer information and | |
289 | * signals completion of the transfer. | |
290 | * | |
291 | * NOTE: This function will be invoked in IRQ context, hence should be | |
292 | * as optimal as possible. | |
293 | */ | |
294 | void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr) | |
295 | { | |
296 | u16 xfer_id = MSG_XTRACT_TOKEN(msg_hdr); | |
297 | u8 msg_type = MSG_XTRACT_TYPE(msg_hdr); | |
298 | ||
299 | switch (msg_type) { | |
300 | case MSG_TYPE_NOTIFICATION: | |
301 | scmi_handle_notification(cinfo, msg_hdr); | |
302 | break; | |
303 | case MSG_TYPE_COMMAND: | |
304 | case MSG_TYPE_DELAYED_RESP: | |
305 | scmi_handle_response(cinfo, xfer_id, msg_type); | |
306 | break; | |
307 | default: | |
308 | WARN_ONCE(1, "received unknown msg_type:%d\n", msg_type); | |
309 | break; | |
310 | } | |
311 | } | |
312 | ||
38c927fb SH |
313 | /** |
314 | * scmi_xfer_put() - Release a transmit message | |
315 | * | |
316 | * @handle: Pointer to SCMI entity handle | |
317 | * @xfer: message that was reserved by scmi_xfer_get | |
318 | */ | |
319 | void scmi_xfer_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) | |
320 | { | |
321 | struct scmi_info *info = handle_to_scmi_info(handle); | |
322 | ||
323 | __scmi_xfer_put(&info->tx_minfo, xfer); | |
324 | } | |
325 | ||
d4c3751a SH |
326 | #define SCMI_MAX_POLL_TO_NS (100 * NSEC_PER_USEC) |
327 | ||
5c8a47a5 | 328 | static bool scmi_xfer_done_no_timeout(struct scmi_chan_info *cinfo, |
d4c3751a SH |
329 | struct scmi_xfer *xfer, ktime_t stop) |
330 | { | |
5c8a47a5 | 331 | struct scmi_info *info = handle_to_scmi_info(cinfo->handle); |
d4c3751a | 332 | |
5c8a47a5 VK |
333 | return info->desc->ops->poll_done(cinfo, xfer) || |
334 | ktime_after(ktime_get(), stop); | |
d4c3751a SH |
335 | } |
336 | ||
aa4f886f SH |
337 | /** |
338 | * scmi_do_xfer() - Do one transfer | |
339 | * | |
1baf47c2 | 340 | * @handle: Pointer to SCMI entity handle |
aa4f886f SH |
341 | * @xfer: Transfer to initiate and wait for response |
342 | * | |
343 | * Return: -ETIMEDOUT in case of no response, if transmit error, | |
1baf47c2 SH |
344 | * return corresponding error, else if all goes well, |
345 | * return 0. | |
aa4f886f SH |
346 | */ |
347 | int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) | |
348 | { | |
349 | int ret; | |
350 | int timeout; | |
351 | struct scmi_info *info = handle_to_scmi_info(handle); | |
352 | struct device *dev = info->dev; | |
907b6d14 SH |
353 | struct scmi_chan_info *cinfo; |
354 | ||
355 | cinfo = idr_find(&info->tx_idr, xfer->hdr.protocol_id); | |
356 | if (unlikely(!cinfo)) | |
357 | return -EINVAL; | |
aa4f886f | 358 | |
729d3530 LL |
359 | trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id, |
360 | xfer->hdr.protocol_id, xfer->hdr.seq, | |
361 | xfer->hdr.poll_completion); | |
362 | ||
5c8a47a5 | 363 | ret = info->desc->ops->send_message(cinfo, xfer); |
aa4f886f | 364 | if (ret < 0) { |
5c8a47a5 | 365 | dev_dbg(dev, "Failed to send message %d\n", ret); |
aa4f886f SH |
366 | return ret; |
367 | } | |
368 | ||
d4c3751a SH |
369 | if (xfer->hdr.poll_completion) { |
370 | ktime_t stop = ktime_add_ns(ktime_get(), SCMI_MAX_POLL_TO_NS); | |
371 | ||
fbc4d81a | 372 | spin_until_cond(scmi_xfer_done_no_timeout(cinfo, xfer, stop)); |
d4c3751a SH |
373 | |
374 | if (ktime_before(ktime_get(), stop)) | |
5c8a47a5 | 375 | info->desc->ops->fetch_response(cinfo, xfer); |
d4c3751a SH |
376 | else |
377 | ret = -ETIMEDOUT; | |
378 | } else { | |
379 | /* And we wait for the response. */ | |
380 | timeout = msecs_to_jiffies(info->desc->max_rx_timeout_ms); | |
381 | if (!wait_for_completion_timeout(&xfer->done, timeout)) { | |
5c8a47a5 | 382 | dev_err(dev, "timed out in resp(caller: %pS)\n", |
d4c3751a SH |
383 | (void *)_RET_IP_); |
384 | ret = -ETIMEDOUT; | |
385 | } | |
aa4f886f | 386 | } |
d4c3751a SH |
387 | |
388 | if (!ret && xfer->hdr.status) | |
389 | ret = scmi_to_linux_errno(xfer->hdr.status); | |
390 | ||
5c8a47a5 VK |
391 | if (info->desc->ops->mark_txdone) |
392 | info->desc->ops->mark_txdone(cinfo, ret); | |
aa4f886f | 393 | |
729d3530 | 394 | trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, |
bad0d73b | 395 | xfer->hdr.protocol_id, xfer->hdr.seq, ret); |
729d3530 | 396 | |
aa4f886f SH |
397 | return ret; |
398 | } | |
399 | ||
58ecdf03 SH |
400 | #define SCMI_MAX_RESPONSE_TIMEOUT (2 * MSEC_PER_SEC) |
401 | ||
402 | /** | |
403 | * scmi_do_xfer_with_response() - Do one transfer and wait until the delayed | |
404 | * response is received | |
405 | * | |
406 | * @handle: Pointer to SCMI entity handle | |
407 | * @xfer: Transfer to initiate and wait for response | |
408 | * | |
409 | * Return: -ETIMEDOUT in case of no delayed response, if transmit error, | |
410 | * return corresponding error, else if all goes well, return 0. | |
411 | */ | |
412 | int scmi_do_xfer_with_response(const struct scmi_handle *handle, | |
413 | struct scmi_xfer *xfer) | |
414 | { | |
415 | int ret, timeout = msecs_to_jiffies(SCMI_MAX_RESPONSE_TIMEOUT); | |
416 | DECLARE_COMPLETION_ONSTACK(async_response); | |
417 | ||
418 | xfer->async_done = &async_response; | |
419 | ||
420 | ret = scmi_do_xfer(handle, xfer); | |
421 | if (!ret && !wait_for_completion_timeout(xfer->async_done, timeout)) | |
422 | ret = -ETIMEDOUT; | |
423 | ||
424 | xfer->async_done = NULL; | |
425 | return ret; | |
426 | } | |
427 | ||
aa4f886f | 428 | /** |
38c927fb | 429 | * scmi_xfer_get_init() - Allocate and initialise one message for transmit |
aa4f886f | 430 | * |
1baf47c2 | 431 | * @handle: Pointer to SCMI entity handle |
aa4f886f | 432 | * @msg_id: Message identifier |
1baf47c2 | 433 | * @prot_id: Protocol identifier for the message |
aa4f886f SH |
434 | * @tx_size: transmit message size |
435 | * @rx_size: receive message size | |
436 | * @p: pointer to the allocated and initialised message | |
437 | * | |
14e297b3 | 438 | * This function allocates the message using @scmi_xfer_get and |
aa4f886f SH |
439 | * initialise the header. |
440 | * | |
441 | * Return: 0 if all went fine with @p pointing to message, else | |
442 | * corresponding error. | |
443 | */ | |
14e297b3 | 444 | int scmi_xfer_get_init(const struct scmi_handle *handle, u8 msg_id, u8 prot_id, |
aa4f886f SH |
445 | size_t tx_size, size_t rx_size, struct scmi_xfer **p) |
446 | { | |
447 | int ret; | |
448 | struct scmi_xfer *xfer; | |
449 | struct scmi_info *info = handle_to_scmi_info(handle); | |
38c927fb | 450 | struct scmi_xfers_info *minfo = &info->tx_minfo; |
aa4f886f SH |
451 | struct device *dev = info->dev; |
452 | ||
453 | /* Ensure we have sane transfer sizes */ | |
454 | if (rx_size > info->desc->max_msg_size || | |
455 | tx_size > info->desc->max_msg_size) | |
456 | return -ERANGE; | |
457 | ||
38c927fb | 458 | xfer = scmi_xfer_get(handle, minfo); |
aa4f886f SH |
459 | if (IS_ERR(xfer)) { |
460 | ret = PTR_ERR(xfer); | |
461 | dev_err(dev, "failed to get free message slot(%d)\n", ret); | |
462 | return ret; | |
463 | } | |
464 | ||
465 | xfer->tx.len = tx_size; | |
466 | xfer->rx.len = rx_size ? : info->desc->max_msg_size; | |
467 | xfer->hdr.id = msg_id; | |
468 | xfer->hdr.protocol_id = prot_id; | |
469 | xfer->hdr.poll_completion = false; | |
470 | ||
471 | *p = xfer; | |
1baf47c2 | 472 | |
aa4f886f SH |
473 | return 0; |
474 | } | |
475 | ||
b6f20ff8 SH |
476 | /** |
477 | * scmi_version_get() - command to get the revision of the SCMI entity | |
478 | * | |
1baf47c2 SH |
479 | * @handle: Pointer to SCMI entity handle |
480 | * @protocol: Protocol identifier for the message | |
481 | * @version: Holds returned version of protocol. | |
b6f20ff8 SH |
482 | * |
483 | * Updates the SCMI information in the internal data structure. | |
484 | * | |
485 | * Return: 0 if all went fine, else return appropriate error. | |
486 | */ | |
487 | int scmi_version_get(const struct scmi_handle *handle, u8 protocol, | |
488 | u32 *version) | |
489 | { | |
490 | int ret; | |
491 | __le32 *rev_info; | |
492 | struct scmi_xfer *t; | |
493 | ||
14e297b3 | 494 | ret = scmi_xfer_get_init(handle, PROTOCOL_VERSION, protocol, 0, |
b6f20ff8 SH |
495 | sizeof(*version), &t); |
496 | if (ret) | |
497 | return ret; | |
498 | ||
499 | ret = scmi_do_xfer(handle, t); | |
500 | if (!ret) { | |
501 | rev_info = t->rx.buf; | |
502 | *version = le32_to_cpu(*rev_info); | |
503 | } | |
504 | ||
14e297b3 | 505 | scmi_xfer_put(handle, t); |
b6f20ff8 SH |
506 | return ret; |
507 | } | |
508 | ||
509 | void scmi_setup_protocol_implemented(const struct scmi_handle *handle, | |
510 | u8 *prot_imp) | |
511 | { | |
512 | struct scmi_info *info = handle_to_scmi_info(handle); | |
513 | ||
514 | info->protocols_imp = prot_imp; | |
515 | } | |
516 | ||
bc40081d SH |
517 | static bool |
518 | scmi_is_protocol_implemented(const struct scmi_handle *handle, u8 prot_id) | |
519 | { | |
520 | int i; | |
521 | struct scmi_info *info = handle_to_scmi_info(handle); | |
522 | ||
523 | if (!info->protocols_imp) | |
524 | return false; | |
525 | ||
526 | for (i = 0; i < MAX_PROTOCOLS_IMP; i++) | |
527 | if (info->protocols_imp[i] == prot_id) | |
528 | return true; | |
529 | return false; | |
530 | } | |
531 | ||
aa4f886f | 532 | /** |
14e297b3 | 533 | * scmi_handle_get() - Get the SCMI handle for a device |
aa4f886f SH |
534 | * |
535 | * @dev: pointer to device for which we want SCMI handle | |
536 | * | |
537 | * NOTE: The function does not track individual clients of the framework | |
1baf47c2 | 538 | * and is expected to be maintained by caller of SCMI protocol library. |
aa4f886f SH |
539 | * scmi_handle_put must be balanced with successful scmi_handle_get |
540 | * | |
541 | * Return: pointer to handle if successful, NULL on error | |
542 | */ | |
543 | struct scmi_handle *scmi_handle_get(struct device *dev) | |
544 | { | |
545 | struct list_head *p; | |
546 | struct scmi_info *info; | |
547 | struct scmi_handle *handle = NULL; | |
548 | ||
549 | mutex_lock(&scmi_list_mutex); | |
550 | list_for_each(p, &scmi_list) { | |
551 | info = list_entry(p, struct scmi_info, node); | |
552 | if (dev->parent == info->dev) { | |
553 | handle = &info->handle; | |
554 | info->users++; | |
555 | break; | |
556 | } | |
557 | } | |
558 | mutex_unlock(&scmi_list_mutex); | |
559 | ||
560 | return handle; | |
561 | } | |
562 | ||
563 | /** | |
564 | * scmi_handle_put() - Release the handle acquired by scmi_handle_get | |
565 | * | |
566 | * @handle: handle acquired by scmi_handle_get | |
567 | * | |
568 | * NOTE: The function does not track individual clients of the framework | |
1baf47c2 | 569 | * and is expected to be maintained by caller of SCMI protocol library. |
aa4f886f SH |
570 | * scmi_handle_put must be balanced with successful scmi_handle_get |
571 | * | |
572 | * Return: 0 is successfully released | |
573 | * if null was passed, it returns -EINVAL; | |
574 | */ | |
575 | int scmi_handle_put(const struct scmi_handle *handle) | |
576 | { | |
577 | struct scmi_info *info; | |
578 | ||
579 | if (!handle) | |
580 | return -EINVAL; | |
581 | ||
582 | info = handle_to_scmi_info(handle); | |
583 | mutex_lock(&scmi_list_mutex); | |
584 | if (!WARN_ON(!info->users)) | |
585 | info->users--; | |
586 | mutex_unlock(&scmi_list_mutex); | |
587 | ||
588 | return 0; | |
589 | } | |
590 | ||
4ebd8f6d SH |
591 | static int __scmi_xfer_info_init(struct scmi_info *sinfo, |
592 | struct scmi_xfers_info *info) | |
aa4f886f SH |
593 | { |
594 | int i; | |
595 | struct scmi_xfer *xfer; | |
596 | struct device *dev = sinfo->dev; | |
597 | const struct scmi_desc *desc = sinfo->desc; | |
aa4f886f SH |
598 | |
599 | /* Pre-allocated messages, no more than what hdr.seq can support */ | |
354b2e36 SH |
600 | if (WARN_ON(desc->max_msg >= MSG_TOKEN_MAX)) { |
601 | dev_err(dev, "Maximum message of %d exceeds supported %ld\n", | |
602 | desc->max_msg, MSG_TOKEN_MAX); | |
aa4f886f SH |
603 | return -EINVAL; |
604 | } | |
605 | ||
606 | info->xfer_block = devm_kcalloc(dev, desc->max_msg, | |
607 | sizeof(*info->xfer_block), GFP_KERNEL); | |
608 | if (!info->xfer_block) | |
609 | return -ENOMEM; | |
610 | ||
611 | info->xfer_alloc_table = devm_kcalloc(dev, BITS_TO_LONGS(desc->max_msg), | |
612 | sizeof(long), GFP_KERNEL); | |
613 | if (!info->xfer_alloc_table) | |
614 | return -ENOMEM; | |
615 | ||
aa4f886f SH |
616 | /* Pre-initialize the buffer pointer to pre-allocated buffers */ |
617 | for (i = 0, xfer = info->xfer_block; i < desc->max_msg; i++, xfer++) { | |
618 | xfer->rx.buf = devm_kcalloc(dev, sizeof(u8), desc->max_msg_size, | |
619 | GFP_KERNEL); | |
620 | if (!xfer->rx.buf) | |
621 | return -ENOMEM; | |
622 | ||
623 | xfer->tx.buf = xfer->rx.buf; | |
624 | init_completion(&xfer->done); | |
625 | } | |
626 | ||
627 | spin_lock_init(&info->xfer_lock); | |
628 | ||
629 | return 0; | |
630 | } | |
631 | ||
4ebd8f6d SH |
632 | static int scmi_xfer_info_init(struct scmi_info *sinfo) |
633 | { | |
634 | int ret = __scmi_xfer_info_init(sinfo, &sinfo->tx_minfo); | |
635 | ||
636 | if (!ret && idr_find(&sinfo->rx_idr, SCMI_PROTOCOL_BASE)) | |
637 | ret = __scmi_xfer_info_init(sinfo, &sinfo->rx_minfo); | |
638 | ||
639 | return ret; | |
640 | } | |
641 | ||
5c8a47a5 VK |
642 | static int scmi_chan_setup(struct scmi_info *info, struct device *dev, |
643 | int prot_id, bool tx) | |
aa4f886f | 644 | { |
3748daf7 | 645 | int ret, idx; |
fbc4d81a | 646 | struct scmi_chan_info *cinfo; |
46cc7c28 | 647 | struct idr *idr; |
3748daf7 SH |
648 | |
649 | /* Transmit channel is first entry i.e. index 0 */ | |
650 | idx = tx ? 0 : 1; | |
46cc7c28 | 651 | idr = tx ? &info->tx_idr : &info->rx_idr; |
aa4f886f | 652 | |
11040889 SH |
653 | /* check if already allocated, used for multiple device per protocol */ |
654 | cinfo = idr_find(idr, prot_id); | |
655 | if (cinfo) | |
656 | return 0; | |
657 | ||
5c8a47a5 | 658 | if (!info->desc->ops->chan_available(dev, idx)) { |
46cc7c28 SH |
659 | cinfo = idr_find(idr, SCMI_PROTOCOL_BASE); |
660 | if (unlikely(!cinfo)) /* Possible only if platform has no Rx */ | |
661 | return -EINVAL; | |
907b6d14 SH |
662 | goto idr_alloc; |
663 | } | |
664 | ||
fbc4d81a SH |
665 | cinfo = devm_kzalloc(info->dev, sizeof(*cinfo), GFP_KERNEL); |
666 | if (!cinfo) | |
667 | return -ENOMEM; | |
668 | ||
fbc4d81a SH |
669 | cinfo->dev = dev; |
670 | ||
5c8a47a5 VK |
671 | ret = info->desc->ops->chan_setup(cinfo, info->dev, tx); |
672 | if (ret) | |
aa4f886f | 673 | return ret; |
aa4f886f | 674 | |
907b6d14 | 675 | idr_alloc: |
46cc7c28 | 676 | ret = idr_alloc(idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL); |
907b6d14 SH |
677 | if (ret != prot_id) { |
678 | dev_err(dev, "unable to allocate SCMI idr slot err %d\n", ret); | |
679 | return ret; | |
680 | } | |
681 | ||
682 | cinfo->handle = &info->handle; | |
aa4f886f SH |
683 | return 0; |
684 | } | |
685 | ||
46cc7c28 | 686 | static inline int |
5c8a47a5 | 687 | scmi_txrx_setup(struct scmi_info *info, struct device *dev, int prot_id) |
46cc7c28 | 688 | { |
5c8a47a5 | 689 | int ret = scmi_chan_setup(info, dev, prot_id, true); |
46cc7c28 SH |
690 | |
691 | if (!ret) /* Rx is optional, hence no error check */ | |
5c8a47a5 | 692 | scmi_chan_setup(info, dev, prot_id, false); |
46cc7c28 SH |
693 | |
694 | return ret; | |
695 | } | |
696 | ||
bc40081d SH |
697 | static inline void |
698 | scmi_create_protocol_device(struct device_node *np, struct scmi_info *info, | |
ee7a9c9f | 699 | int prot_id, const char *name) |
bc40081d SH |
700 | { |
701 | struct scmi_device *sdev; | |
702 | ||
ee7a9c9f | 703 | sdev = scmi_device_create(np, info->dev, prot_id, name); |
bc40081d SH |
704 | if (!sdev) { |
705 | dev_err(info->dev, "failed to create %d protocol device\n", | |
706 | prot_id); | |
707 | return; | |
708 | } | |
709 | ||
5c8a47a5 | 710 | if (scmi_txrx_setup(info, &sdev->dev, prot_id)) { |
907b6d14 SH |
711 | dev_err(&sdev->dev, "failed to setup transport\n"); |
712 | scmi_device_destroy(sdev); | |
31c60855 | 713 | return; |
907b6d14 SH |
714 | } |
715 | ||
bc40081d SH |
716 | /* setup handle now as the transport is ready */ |
717 | scmi_set_handle(sdev); | |
718 | } | |
719 | ||
9c5c463f SH |
720 | #define MAX_SCMI_DEV_PER_PROTOCOL 2 |
721 | struct scmi_prot_devnames { | |
722 | int protocol_id; | |
723 | char *names[MAX_SCMI_DEV_PER_PROTOCOL]; | |
724 | }; | |
725 | ||
726 | static struct scmi_prot_devnames devnames[] = { | |
727 | { SCMI_PROTOCOL_POWER, { "genpd" },}, | |
728 | { SCMI_PROTOCOL_PERF, { "cpufreq" },}, | |
729 | { SCMI_PROTOCOL_CLOCK, { "clocks" },}, | |
730 | { SCMI_PROTOCOL_SENSOR, { "hwmon" },}, | |
731 | { SCMI_PROTOCOL_RESET, { "reset" },}, | |
732 | }; | |
733 | ||
734 | static inline void | |
735 | scmi_create_protocol_devices(struct device_node *np, struct scmi_info *info, | |
736 | int prot_id) | |
737 | { | |
738 | int loop, cnt; | |
739 | ||
740 | for (loop = 0; loop < ARRAY_SIZE(devnames); loop++) { | |
741 | if (devnames[loop].protocol_id != prot_id) | |
742 | continue; | |
743 | ||
744 | for (cnt = 0; cnt < ARRAY_SIZE(devnames[loop].names); cnt++) { | |
745 | const char *name = devnames[loop].names[cnt]; | |
746 | ||
747 | if (name) | |
748 | scmi_create_protocol_device(np, info, prot_id, | |
749 | name); | |
750 | } | |
751 | } | |
752 | } | |
753 | ||
aa4f886f SH |
754 | static int scmi_probe(struct platform_device *pdev) |
755 | { | |
756 | int ret; | |
757 | struct scmi_handle *handle; | |
758 | const struct scmi_desc *desc; | |
759 | struct scmi_info *info; | |
760 | struct device *dev = &pdev->dev; | |
bc40081d | 761 | struct device_node *child, *np = dev->of_node; |
aa4f886f | 762 | |
d9350f21 AP |
763 | desc = of_device_get_match_data(dev); |
764 | if (!desc) | |
765 | return -EINVAL; | |
aa4f886f SH |
766 | |
767 | info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); | |
768 | if (!info) | |
769 | return -ENOMEM; | |
770 | ||
771 | info->dev = dev; | |
772 | info->desc = desc; | |
773 | INIT_LIST_HEAD(&info->node); | |
774 | ||
aa4f886f | 775 | platform_set_drvdata(pdev, info); |
907b6d14 | 776 | idr_init(&info->tx_idr); |
46cc7c28 | 777 | idr_init(&info->rx_idr); |
aa4f886f SH |
778 | |
779 | handle = &info->handle; | |
780 | handle->dev = info->dev; | |
b6f20ff8 | 781 | handle->version = &info->version; |
aa4f886f | 782 | |
5c8a47a5 | 783 | ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE); |
aa4f886f SH |
784 | if (ret) |
785 | return ret; | |
786 | ||
4ebd8f6d SH |
787 | ret = scmi_xfer_info_init(info); |
788 | if (ret) | |
789 | return ret; | |
790 | ||
b6f20ff8 SH |
791 | ret = scmi_base_protocol_init(handle); |
792 | if (ret) { | |
793 | dev_err(dev, "unable to communicate with SCMI(%d)\n", ret); | |
b6f20ff8 SH |
794 | return ret; |
795 | } | |
796 | ||
aa4f886f SH |
797 | mutex_lock(&scmi_list_mutex); |
798 | list_add_tail(&info->node, &scmi_list); | |
799 | mutex_unlock(&scmi_list_mutex); | |
800 | ||
bc40081d SH |
801 | for_each_available_child_of_node(np, child) { |
802 | u32 prot_id; | |
803 | ||
804 | if (of_property_read_u32(child, "reg", &prot_id)) | |
805 | continue; | |
806 | ||
354b2e36 SH |
807 | if (!FIELD_FIT(MSG_PROTOCOL_ID_MASK, prot_id)) |
808 | dev_err(dev, "Out of range protocol %d\n", prot_id); | |
bc40081d SH |
809 | |
810 | if (!scmi_is_protocol_implemented(handle, prot_id)) { | |
811 | dev_err(dev, "SCMI protocol %d not implemented\n", | |
812 | prot_id); | |
813 | continue; | |
814 | } | |
815 | ||
9c5c463f | 816 | scmi_create_protocol_devices(child, info, prot_id); |
bc40081d SH |
817 | } |
818 | ||
aa4f886f SH |
819 | return 0; |
820 | } | |
821 | ||
5c8a47a5 | 822 | void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id) |
2747a967 | 823 | { |
2747a967 | 824 | idr_remove(idr, id); |
2747a967 SH |
825 | } |
826 | ||
827 | static int scmi_remove(struct platform_device *pdev) | |
828 | { | |
829 | int ret = 0; | |
830 | struct scmi_info *info = platform_get_drvdata(pdev); | |
831 | struct idr *idr = &info->tx_idr; | |
832 | ||
833 | mutex_lock(&scmi_list_mutex); | |
834 | if (info->users) | |
835 | ret = -EBUSY; | |
836 | else | |
837 | list_del(&info->node); | |
838 | mutex_unlock(&scmi_list_mutex); | |
839 | ||
840 | if (ret) | |
841 | return ret; | |
842 | ||
843 | /* Safe to free channels since no more users */ | |
5c8a47a5 | 844 | ret = idr_for_each(idr, info->desc->ops->chan_free, idr); |
2747a967 SH |
845 | idr_destroy(&info->tx_idr); |
846 | ||
46cc7c28 | 847 | idr = &info->rx_idr; |
5c8a47a5 | 848 | ret = idr_for_each(idr, info->desc->ops->chan_free, idr); |
46cc7c28 SH |
849 | idr_destroy(&info->rx_idr); |
850 | ||
2747a967 SH |
851 | return ret; |
852 | } | |
853 | ||
4605e224 SH |
854 | static ssize_t protocol_version_show(struct device *dev, |
855 | struct device_attribute *attr, char *buf) | |
856 | { | |
857 | struct scmi_info *info = dev_get_drvdata(dev); | |
858 | ||
859 | return sprintf(buf, "%u.%u\n", info->version.major_ver, | |
860 | info->version.minor_ver); | |
861 | } | |
862 | static DEVICE_ATTR_RO(protocol_version); | |
863 | ||
864 | static ssize_t firmware_version_show(struct device *dev, | |
865 | struct device_attribute *attr, char *buf) | |
866 | { | |
867 | struct scmi_info *info = dev_get_drvdata(dev); | |
868 | ||
869 | return sprintf(buf, "0x%x\n", info->version.impl_ver); | |
870 | } | |
871 | static DEVICE_ATTR_RO(firmware_version); | |
872 | ||
873 | static ssize_t vendor_id_show(struct device *dev, | |
874 | struct device_attribute *attr, char *buf) | |
875 | { | |
876 | struct scmi_info *info = dev_get_drvdata(dev); | |
877 | ||
878 | return sprintf(buf, "%s\n", info->version.vendor_id); | |
879 | } | |
880 | static DEVICE_ATTR_RO(vendor_id); | |
881 | ||
882 | static ssize_t sub_vendor_id_show(struct device *dev, | |
883 | struct device_attribute *attr, char *buf) | |
884 | { | |
885 | struct scmi_info *info = dev_get_drvdata(dev); | |
886 | ||
887 | return sprintf(buf, "%s\n", info->version.sub_vendor_id); | |
888 | } | |
889 | static DEVICE_ATTR_RO(sub_vendor_id); | |
890 | ||
891 | static struct attribute *versions_attrs[] = { | |
892 | &dev_attr_firmware_version.attr, | |
893 | &dev_attr_protocol_version.attr, | |
894 | &dev_attr_vendor_id.attr, | |
895 | &dev_attr_sub_vendor_id.attr, | |
896 | NULL, | |
897 | }; | |
898 | ATTRIBUTE_GROUPS(versions); | |
899 | ||
2747a967 SH |
900 | /* Each compatible listed below must have descriptor associated with it */ |
901 | static const struct of_device_id scmi_of_match[] = { | |
5c8a47a5 | 902 | { .compatible = "arm,scmi", .data = &scmi_mailbox_desc }, |
d7642823 | 903 | #ifdef CONFIG_HAVE_ARM_SMCCC_DISCOVERY |
1dc65580 PF |
904 | { .compatible = "arm,scmi-smc", .data = &scmi_smc_desc}, |
905 | #endif | |
2747a967 SH |
906 | { /* Sentinel */ }, |
907 | }; | |
908 | ||
909 | MODULE_DEVICE_TABLE(of, scmi_of_match); | |
910 | ||
aa4f886f SH |
911 | static struct platform_driver scmi_driver = { |
912 | .driver = { | |
913 | .name = "arm-scmi", | |
914 | .of_match_table = scmi_of_match, | |
4605e224 | 915 | .dev_groups = versions_groups, |
aa4f886f SH |
916 | }, |
917 | .probe = scmi_probe, | |
918 | .remove = scmi_remove, | |
919 | }; | |
920 | ||
921 | module_platform_driver(scmi_driver); | |
922 | ||
923 | MODULE_ALIAS("platform: arm-scmi"); | |
924 | MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>"); | |
925 | MODULE_DESCRIPTION("ARM SCMI protocol driver"); | |
926 | MODULE_LICENSE("GPL v2"); |