1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * System Control and Power Interface (SCPI) Message Protocol driver
4 *
5 * SCPI 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) 2015 ARM Ltd.
15 */
16
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19 #include <linux/bitmap.h>
20 #include <linux/bitfield.h>
21 #include <linux/cleanup.h>
22 #include <linux/device.h>
23 #include <linux/err.h>
24 #include <linux/export.h>
25 #include <linux/io.h>
26 #include <linux/kernel.h>
27 #include <linux/list.h>
28 #include <linux/mailbox_client.h>
29 #include <linux/module.h>
30 #include <linux/of.h>
31 #include <linux/of_address.h>
32 #include <linux/of_platform.h>
33 #include <linux/platform_device.h>
34 #include <linux/printk.h>
35 #include <linux/property.h>
36 #include <linux/pm_opp.h>
37 #include <linux/scpi_protocol.h>
38 #include <linux/slab.h>
39 #include <linux/sort.h>
40 #include <linux/spinlock.h>
41
42 #define CMD_ID_MASK GENMASK(6, 0)
43 #define CMD_TOKEN_ID_MASK GENMASK(15, 8)
44 #define CMD_DATA_SIZE_MASK GENMASK(24, 16)
45 #define CMD_LEGACY_DATA_SIZE_MASK GENMASK(28, 20)
46 #define PACK_SCPI_CMD(cmd_id, tx_sz) \
47 (FIELD_PREP(CMD_ID_MASK, cmd_id) | \
48 FIELD_PREP(CMD_DATA_SIZE_MASK, tx_sz))
49 #define PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz) \
50 (FIELD_PREP(CMD_ID_MASK, cmd_id) | \
51 FIELD_PREP(CMD_LEGACY_DATA_SIZE_MASK, tx_sz))
52
53 #define CMD_SIZE(cmd) FIELD_GET(CMD_DATA_SIZE_MASK, cmd)
54 #define CMD_UNIQ_MASK (CMD_TOKEN_ID_MASK | CMD_ID_MASK)
55 #define CMD_XTRACT_UNIQ(cmd) ((cmd) & CMD_UNIQ_MASK)
56
57 #define SCPI_SLOT 0
58
59 #define MAX_DVFS_DOMAINS 8
60 #define MAX_DVFS_OPPS 16
61
62 #define PROTO_REV_MAJOR_MASK GENMASK(31, 16)
63 #define PROTO_REV_MINOR_MASK GENMASK(15, 0)
64
65 #define FW_REV_MAJOR_MASK GENMASK(31, 24)
66 #define FW_REV_MINOR_MASK GENMASK(23, 16)
67 #define FW_REV_PATCH_MASK GENMASK(15, 0)
68
69 #define MAX_RX_TIMEOUT (msecs_to_jiffies(30))
70
71 enum scpi_error_codes {
72 SCPI_SUCCESS = 0, /* Success */
73 SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
74 SCPI_ERR_ALIGN = 2, /* Invalid alignment */
75 SCPI_ERR_SIZE = 3, /* Invalid size */
76 SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
77 SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
78 SCPI_ERR_RANGE = 6, /* Value out of range */
79 SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
80 SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
81 SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
82 SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
83 SCPI_ERR_DEVICE = 11, /* Device error */
84 SCPI_ERR_BUSY = 12, /* Device busy */
85 SCPI_ERR_MAX
86 };
87
88 /* SCPI Standard commands */
89 enum scpi_std_cmd {
90 SCPI_CMD_INVALID = 0x00,
91 SCPI_CMD_SCPI_READY = 0x01,
92 SCPI_CMD_SCPI_CAPABILITIES = 0x02,
93 SCPI_CMD_SET_CSS_PWR_STATE = 0x03,
94 SCPI_CMD_GET_CSS_PWR_STATE = 0x04,
95 SCPI_CMD_SET_SYS_PWR_STATE = 0x05,
96 SCPI_CMD_SET_CPU_TIMER = 0x06,
97 SCPI_CMD_CANCEL_CPU_TIMER = 0x07,
98 SCPI_CMD_DVFS_CAPABILITIES = 0x08,
99 SCPI_CMD_GET_DVFS_INFO = 0x09,
100 SCPI_CMD_SET_DVFS = 0x0a,
101 SCPI_CMD_GET_DVFS = 0x0b,
102 SCPI_CMD_GET_DVFS_STAT = 0x0c,
103 SCPI_CMD_CLOCK_CAPABILITIES = 0x0d,
104 SCPI_CMD_GET_CLOCK_INFO = 0x0e,
105 SCPI_CMD_SET_CLOCK_VALUE = 0x0f,
106 SCPI_CMD_GET_CLOCK_VALUE = 0x10,
107 SCPI_CMD_PSU_CAPABILITIES = 0x11,
108 SCPI_CMD_GET_PSU_INFO = 0x12,
109 SCPI_CMD_SET_PSU = 0x13,
110 SCPI_CMD_GET_PSU = 0x14,
111 SCPI_CMD_SENSOR_CAPABILITIES = 0x15,
112 SCPI_CMD_SENSOR_INFO = 0x16,
113 SCPI_CMD_SENSOR_VALUE = 0x17,
114 SCPI_CMD_SENSOR_CFG_PERIODIC = 0x18,
115 SCPI_CMD_SENSOR_CFG_BOUNDS = 0x19,
116 SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1a,
117 SCPI_CMD_SET_DEVICE_PWR_STATE = 0x1b,
118 SCPI_CMD_GET_DEVICE_PWR_STATE = 0x1c,
119 SCPI_CMD_COUNT
120 };
121
122 /* SCPI Legacy Commands */
123 enum legacy_scpi_std_cmd {
124 LEGACY_SCPI_CMD_INVALID = 0x00,
125 LEGACY_SCPI_CMD_SCPI_READY = 0x01,
126 LEGACY_SCPI_CMD_SCPI_CAPABILITIES = 0x02,
127 LEGACY_SCPI_CMD_EVENT = 0x03,
128 LEGACY_SCPI_CMD_SET_CSS_PWR_STATE = 0x04,
129 LEGACY_SCPI_CMD_GET_CSS_PWR_STATE = 0x05,
130 LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT = 0x06,
131 LEGACY_SCPI_CMD_GET_PWR_STATE_STAT = 0x07,
132 LEGACY_SCPI_CMD_SYS_PWR_STATE = 0x08,
133 LEGACY_SCPI_CMD_L2_READY = 0x09,
134 LEGACY_SCPI_CMD_SET_AP_TIMER = 0x0a,
135 LEGACY_SCPI_CMD_CANCEL_AP_TIME = 0x0b,
136 LEGACY_SCPI_CMD_DVFS_CAPABILITIES = 0x0c,
137 LEGACY_SCPI_CMD_GET_DVFS_INFO = 0x0d,
138 LEGACY_SCPI_CMD_SET_DVFS = 0x0e,
139 LEGACY_SCPI_CMD_GET_DVFS = 0x0f,
140 LEGACY_SCPI_CMD_GET_DVFS_STAT = 0x10,
141 LEGACY_SCPI_CMD_SET_RTC = 0x11,
142 LEGACY_SCPI_CMD_GET_RTC = 0x12,
143 LEGACY_SCPI_CMD_CLOCK_CAPABILITIES = 0x13,
144 LEGACY_SCPI_CMD_SET_CLOCK_INDEX = 0x14,
145 LEGACY_SCPI_CMD_SET_CLOCK_VALUE = 0x15,
146 LEGACY_SCPI_CMD_GET_CLOCK_VALUE = 0x16,
147 LEGACY_SCPI_CMD_PSU_CAPABILITIES = 0x17,
148 LEGACY_SCPI_CMD_SET_PSU = 0x18,
149 LEGACY_SCPI_CMD_GET_PSU = 0x19,
150 LEGACY_SCPI_CMD_SENSOR_CAPABILITIES = 0x1a,
151 LEGACY_SCPI_CMD_SENSOR_INFO = 0x1b,
152 LEGACY_SCPI_CMD_SENSOR_VALUE = 0x1c,
153 LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC = 0x1d,
154 LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS = 0x1e,
155 LEGACY_SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1f,
156 LEGACY_SCPI_CMD_COUNT
157 };
158
159 /* List all commands that are required to go through the high priority link */
160 static int legacy_hpriority_cmds[] = {
161 LEGACY_SCPI_CMD_GET_CSS_PWR_STATE,
162 LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT,
163 LEGACY_SCPI_CMD_GET_PWR_STATE_STAT,
164 LEGACY_SCPI_CMD_SET_DVFS,
165 LEGACY_SCPI_CMD_GET_DVFS,
166 LEGACY_SCPI_CMD_SET_RTC,
167 LEGACY_SCPI_CMD_GET_RTC,
168 LEGACY_SCPI_CMD_SET_CLOCK_INDEX,
169 LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
170 LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
171 LEGACY_SCPI_CMD_SET_PSU,
172 LEGACY_SCPI_CMD_GET_PSU,
173 LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC,
174 LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS,
175 };
176
177 /* List all commands used by this driver, used as indexes */
178 enum scpi_drv_cmds {
179 CMD_SCPI_CAPABILITIES = 0,
180 CMD_GET_CLOCK_INFO,
181 CMD_GET_CLOCK_VALUE,
182 CMD_SET_CLOCK_VALUE,
183 CMD_GET_DVFS,
184 CMD_SET_DVFS,
185 CMD_GET_DVFS_INFO,
186 CMD_SENSOR_CAPABILITIES,
187 CMD_SENSOR_INFO,
188 CMD_SENSOR_VALUE,
189 CMD_SET_DEVICE_PWR_STATE,
190 CMD_GET_DEVICE_PWR_STATE,
191 CMD_MAX_COUNT,
192 };
193
194 static int scpi_std_commands[CMD_MAX_COUNT] = {
195 SCPI_CMD_SCPI_CAPABILITIES,
196 SCPI_CMD_GET_CLOCK_INFO,
197 SCPI_CMD_GET_CLOCK_VALUE,
198 SCPI_CMD_SET_CLOCK_VALUE,
199 SCPI_CMD_GET_DVFS,
200 SCPI_CMD_SET_DVFS,
201 SCPI_CMD_GET_DVFS_INFO,
202 SCPI_CMD_SENSOR_CAPABILITIES,
203 SCPI_CMD_SENSOR_INFO,
204 SCPI_CMD_SENSOR_VALUE,
205 SCPI_CMD_SET_DEVICE_PWR_STATE,
206 SCPI_CMD_GET_DEVICE_PWR_STATE,
207 };
208
209 static int scpi_legacy_commands[CMD_MAX_COUNT] = {
210 LEGACY_SCPI_CMD_SCPI_CAPABILITIES,
211 -1, /* GET_CLOCK_INFO */
212 LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
213 LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
214 LEGACY_SCPI_CMD_GET_DVFS,
215 LEGACY_SCPI_CMD_SET_DVFS,
216 LEGACY_SCPI_CMD_GET_DVFS_INFO,
217 LEGACY_SCPI_CMD_SENSOR_CAPABILITIES,
218 LEGACY_SCPI_CMD_SENSOR_INFO,
219 LEGACY_SCPI_CMD_SENSOR_VALUE,
220 -1, /* SET_DEVICE_PWR_STATE */
221 -1, /* GET_DEVICE_PWR_STATE */
222 };
223
224 struct scpi_xfer {
225 u32 slot; /* has to be first element */
226 u32 cmd;
227 u32 status;
228 const void *tx_buf;
229 void *rx_buf;
230 unsigned int tx_len;
231 unsigned int rx_len;
232 struct list_head node;
233 struct completion done;
234 };
235
236 struct scpi_chan {
237 struct mbox_client cl;
238 struct mbox_chan *chan;
239 void __iomem *tx_payload;
240 void __iomem *rx_payload;
241 struct list_head rx_pending;
242 struct list_head xfers_list;
243 struct scpi_xfer *xfers;
244 spinlock_t rx_lock; /* locking for the rx pending list */
245 struct mutex xfers_lock;
246 u8 token;
247 };
248
249 struct scpi_drvinfo {
250 u32 protocol_version;
251 u32 firmware_version;
252 bool is_legacy;
253 int num_chans;
254 int *commands;
255 DECLARE_BITMAP(cmd_priority, LEGACY_SCPI_CMD_COUNT);
256 atomic_t next_chan;
257 struct scpi_ops *scpi_ops;
258 struct scpi_chan *channels;
259 struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
260 };
261
262 /*
263 * The SCP firmware only executes in little-endian mode, so any buffers
264 * shared through SCPI should have their contents converted to little-endian
265 */
266 struct scpi_shared_mem {
267 __le32 command;
268 __le32 status;
269 u8 payload[];
270 } __packed;
271
272 struct legacy_scpi_shared_mem {
273 __le32 status;
274 u8 payload[];
275 } __packed;
276
277 struct scp_capabilities {
278 __le32 protocol_version;
279 __le32 event_version;
280 __le32 platform_version;
281 __le32 commands[4];
282 } __packed;
283
284 struct clk_get_info {
285 __le16 id;
286 __le16 flags;
287 __le32 min_rate;
288 __le32 max_rate;
289 u8 name[20];
290 } __packed;
291
292 struct clk_set_value {
293 __le16 id;
294 __le16 reserved;
295 __le32 rate;
296 } __packed;
297
298 struct legacy_clk_set_value {
299 __le32 rate;
300 __le16 id;
301 __le16 reserved;
302 } __packed;
303
304 struct dvfs_info {
305 u8 domain;
306 u8 opp_count;
307 __le16 latency;
308 struct {
309 __le32 freq;
310 __le32 m_volt;
311 } opps[MAX_DVFS_OPPS];
312 } __packed;
313
314 struct dvfs_set {
315 u8 domain;
316 u8 index;
317 } __packed;
318
319 struct _scpi_sensor_info {
320 __le16 sensor_id;
321 u8 class;
322 u8 trigger_type;
323 char name[20];
324 };
325
326 struct dev_pstate_set {
327 __le16 dev_id;
328 u8 pstate;
329 } __packed;
330
331 static struct scpi_drvinfo *scpi_info;
332
333 static int scpi_linux_errmap[SCPI_ERR_MAX] = {
334 /* better than switch case as long as return value is continuous */
335 0, /* SCPI_SUCCESS */
336 -EINVAL, /* SCPI_ERR_PARAM */
337 -ENOEXEC, /* SCPI_ERR_ALIGN */
338 -EMSGSIZE, /* SCPI_ERR_SIZE */
339 -EINVAL, /* SCPI_ERR_HANDLER */
340 -EACCES, /* SCPI_ERR_ACCESS */
341 -ERANGE, /* SCPI_ERR_RANGE */
342 -ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
343 -ENOMEM, /* SCPI_ERR_NOMEM */
344 -EINVAL, /* SCPI_ERR_PWRSTATE */
345 -EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
346 -EIO, /* SCPI_ERR_DEVICE */
347 -EBUSY, /* SCPI_ERR_BUSY */
348 };
349
scpi_to_linux_errno(int errno)350 static inline int scpi_to_linux_errno(int errno)
351 {
352 if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
353 return scpi_linux_errmap[errno];
354 return -EIO;
355 }
356
scpi_process_cmd(struct scpi_chan * ch,u32 cmd)357 static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
358 {
359 unsigned long flags;
360 struct scpi_xfer *t, *match = NULL;
361
362 spin_lock_irqsave(&ch->rx_lock, flags);
363 if (list_empty(&ch->rx_pending)) {
364 spin_unlock_irqrestore(&ch->rx_lock, flags);
365 return;
366 }
367
368 /* Command type is not replied by the SCP Firmware in legacy Mode
369 * We should consider that command is the head of pending RX commands
370 * if the list is not empty. In TX only mode, the list would be empty.
371 */
372 if (scpi_info->is_legacy) {
373 match = list_first_entry(&ch->rx_pending, struct scpi_xfer,
374 node);
375 list_del(&match->node);
376 } else {
377 list_for_each_entry(t, &ch->rx_pending, node)
378 if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
379 list_del(&t->node);
380 match = t;
381 break;
382 }
383 }
384 /* check if wait_for_completion is in progress or timed-out */
385 if (match && !completion_done(&match->done)) {
386 unsigned int len;
387
388 if (scpi_info->is_legacy) {
389 struct legacy_scpi_shared_mem __iomem *mem =
390 ch->rx_payload;
391
392 /* RX Length is not replied by the legacy Firmware */
393 len = match->rx_len;
394
395 match->status = ioread32(&mem->status);
396 memcpy_fromio(match->rx_buf, mem->payload, len);
397 } else {
398 struct scpi_shared_mem __iomem *mem = ch->rx_payload;
399
400 len = min_t(unsigned int, match->rx_len, CMD_SIZE(cmd));
401
402 match->status = ioread32(&mem->status);
403 memcpy_fromio(match->rx_buf, mem->payload, len);
404 }
405
406 if (match->rx_len > len)
407 memset(match->rx_buf + len, 0, match->rx_len - len);
408 complete(&match->done);
409 }
410 spin_unlock_irqrestore(&ch->rx_lock, flags);
411 }
412
scpi_handle_remote_msg(struct mbox_client * c,void * msg)413 static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
414 {
415 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
416 struct scpi_shared_mem __iomem *mem = ch->rx_payload;
417 u32 cmd = 0;
418
419 if (!scpi_info->is_legacy)
420 cmd = ioread32(&mem->command);
421
422 scpi_process_cmd(ch, cmd);
423 }
424
scpi_tx_prepare(struct mbox_client * c,void * msg)425 static void scpi_tx_prepare(struct mbox_client *c, void *msg)
426 {
427 unsigned long flags;
428 struct scpi_xfer *t = msg;
429 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
430 struct scpi_shared_mem __iomem *mem = ch->tx_payload;
431
432 if (t->tx_buf) {
433 if (scpi_info->is_legacy)
434 memcpy_toio(ch->tx_payload, t->tx_buf, t->tx_len);
435 else
436 memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
437 }
438
439 if (t->rx_buf) {
440 if (!(++ch->token))
441 ++ch->token;
442 t->cmd |= FIELD_PREP(CMD_TOKEN_ID_MASK, ch->token);
443 spin_lock_irqsave(&ch->rx_lock, flags);
444 list_add_tail(&t->node, &ch->rx_pending);
445 spin_unlock_irqrestore(&ch->rx_lock, flags);
446 }
447
448 if (!scpi_info->is_legacy)
449 iowrite32(t->cmd, &mem->command);
450 }
451
get_scpi_xfer(struct scpi_chan * ch)452 static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
453 {
454 struct scpi_xfer *t;
455
456 mutex_lock(&ch->xfers_lock);
457 if (list_empty(&ch->xfers_list)) {
458 mutex_unlock(&ch->xfers_lock);
459 return NULL;
460 }
461 t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
462 list_del(&t->node);
463 mutex_unlock(&ch->xfers_lock);
464 return t;
465 }
466
put_scpi_xfer(struct scpi_xfer * t,struct scpi_chan * ch)467 static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
468 {
469 mutex_lock(&ch->xfers_lock);
470 list_add_tail(&t->node, &ch->xfers_list);
471 mutex_unlock(&ch->xfers_lock);
472 }
473
scpi_send_message(u8 idx,void * tx_buf,unsigned int tx_len,void * rx_buf,unsigned int rx_len)474 static int scpi_send_message(u8 idx, void *tx_buf, unsigned int tx_len,
475 void *rx_buf, unsigned int rx_len)
476 {
477 int ret;
478 u8 chan;
479 u8 cmd;
480 struct scpi_xfer *msg;
481 struct scpi_chan *scpi_chan;
482
483 if (scpi_info->commands[idx] < 0)
484 return -EOPNOTSUPP;
485
486 cmd = scpi_info->commands[idx];
487
488 if (scpi_info->is_legacy)
489 chan = test_bit(cmd, scpi_info->cmd_priority) ? 1 : 0;
490 else
491 chan = atomic_inc_return(&scpi_info->next_chan) %
492 scpi_info->num_chans;
493 scpi_chan = scpi_info->channels + chan;
494
495 msg = get_scpi_xfer(scpi_chan);
496 if (!msg)
497 return -ENOMEM;
498
499 if (scpi_info->is_legacy) {
500 msg->cmd = PACK_LEGACY_SCPI_CMD(cmd, tx_len);
501 msg->slot = msg->cmd;
502 } else {
503 msg->slot = BIT(SCPI_SLOT);
504 msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
505 }
506 msg->tx_buf = tx_buf;
507 msg->tx_len = tx_len;
508 msg->rx_buf = rx_buf;
509 msg->rx_len = rx_len;
510 reinit_completion(&msg->done);
511
512 ret = mbox_send_message(scpi_chan->chan, msg);
513 if (ret < 0 || !rx_buf)
514 goto out;
515
516 if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
517 ret = -ETIMEDOUT;
518 else
519 /* first status word */
520 ret = msg->status;
521 out:
522 if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
523 scpi_process_cmd(scpi_chan, msg->cmd);
524
525 put_scpi_xfer(msg, scpi_chan);
526 /* SCPI error codes > 0, translate them to Linux scale*/
527 return ret > 0 ? scpi_to_linux_errno(ret) : ret;
528 }
529
scpi_get_version(void)530 static u32 scpi_get_version(void)
531 {
532 return scpi_info->protocol_version;
533 }
534
535 static int
scpi_clk_get_range(u16 clk_id,unsigned long * min,unsigned long * max)536 scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
537 {
538 int ret;
539 struct clk_get_info clk;
540 __le16 le_clk_id = cpu_to_le16(clk_id);
541
542 ret = scpi_send_message(CMD_GET_CLOCK_INFO, &le_clk_id,
543 sizeof(le_clk_id), &clk, sizeof(clk));
544 if (!ret) {
545 *min = le32_to_cpu(clk.min_rate);
546 *max = le32_to_cpu(clk.max_rate);
547 }
548 return ret;
549 }
550
scpi_clk_get_val(u16 clk_id)551 static unsigned long scpi_clk_get_val(u16 clk_id)
552 {
553 int ret;
554 __le32 rate;
555 __le16 le_clk_id = cpu_to_le16(clk_id);
556
557 ret = scpi_send_message(CMD_GET_CLOCK_VALUE, &le_clk_id,
558 sizeof(le_clk_id), &rate, sizeof(rate));
559 if (ret)
560 return 0;
561
562 return le32_to_cpu(rate);
563 }
564
scpi_clk_set_val(u16 clk_id,unsigned long rate)565 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
566 {
567 int stat;
568 struct clk_set_value clk = {
569 .id = cpu_to_le16(clk_id),
570 .rate = cpu_to_le32(rate)
571 };
572
573 return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
574 &stat, sizeof(stat));
575 }
576
legacy_scpi_clk_set_val(u16 clk_id,unsigned long rate)577 static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
578 {
579 int stat;
580 struct legacy_clk_set_value clk = {
581 .id = cpu_to_le16(clk_id),
582 .rate = cpu_to_le32(rate)
583 };
584
585 return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
586 &stat, sizeof(stat));
587 }
588
scpi_dvfs_get_idx(u8 domain)589 static int scpi_dvfs_get_idx(u8 domain)
590 {
591 int ret;
592 u8 dvfs_idx;
593
594 ret = scpi_send_message(CMD_GET_DVFS, &domain, sizeof(domain),
595 &dvfs_idx, sizeof(dvfs_idx));
596
597 return ret ? ret : dvfs_idx;
598 }
599
scpi_dvfs_set_idx(u8 domain,u8 index)600 static int scpi_dvfs_set_idx(u8 domain, u8 index)
601 {
602 int stat;
603 struct dvfs_set dvfs = {domain, index};
604
605 return scpi_send_message(CMD_SET_DVFS, &dvfs, sizeof(dvfs),
606 &stat, sizeof(stat));
607 }
608
opp_cmp_func(const void * opp1,const void * opp2)609 static int opp_cmp_func(const void *opp1, const void *opp2)
610 {
611 const struct scpi_opp *t1 = opp1, *t2 = opp2;
612
613 return t1->freq - t2->freq;
614 }
615
scpi_dvfs_get_info(u8 domain)616 static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
617 {
618 struct scpi_dvfs_info *info;
619 struct scpi_opp *opp;
620 struct dvfs_info buf;
621 int ret, i;
622
623 if (domain >= MAX_DVFS_DOMAINS)
624 return ERR_PTR(-EINVAL);
625
626 if (scpi_info->dvfs[domain]) /* data already populated */
627 return scpi_info->dvfs[domain];
628
629 ret = scpi_send_message(CMD_GET_DVFS_INFO, &domain, sizeof(domain),
630 &buf, sizeof(buf));
631 if (ret)
632 return ERR_PTR(ret);
633
634 if (!buf.opp_count)
635 return ERR_PTR(-ENOENT);
636
637 info = kmalloc_obj(*info);
638 if (!info)
639 return ERR_PTR(-ENOMEM);
640
641 info->count = buf.opp_count;
642 info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
643
644 info->opps = kzalloc_objs(*opp, info->count);
645 if (!info->opps) {
646 kfree(info);
647 return ERR_PTR(-ENOMEM);
648 }
649
650 for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
651 opp->freq = le32_to_cpu(buf.opps[i].freq);
652 opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
653 }
654
655 sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
656
657 scpi_info->dvfs[domain] = info;
658 return info;
659 }
660
scpi_dev_domain_id(struct device * dev)661 static int scpi_dev_domain_id(struct device *dev)
662 {
663 struct of_phandle_args clkspec;
664
665 if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
666 0, &clkspec))
667 return -EINVAL;
668
669 return clkspec.args[0];
670 }
671
scpi_dvfs_info(struct device * dev)672 static struct scpi_dvfs_info *scpi_dvfs_info(struct device *dev)
673 {
674 int domain = scpi_dev_domain_id(dev);
675
676 if (domain < 0)
677 return ERR_PTR(domain);
678
679 return scpi_dvfs_get_info(domain);
680 }
681
scpi_dvfs_get_transition_latency(struct device * dev)682 static int scpi_dvfs_get_transition_latency(struct device *dev)
683 {
684 struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
685
686 if (IS_ERR(info))
687 return PTR_ERR(info);
688
689 return info->latency;
690 }
691
scpi_dvfs_add_opps_to_device(struct device * dev)692 static int scpi_dvfs_add_opps_to_device(struct device *dev)
693 {
694 int idx, ret;
695 struct scpi_opp *opp;
696 struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
697
698 if (IS_ERR(info))
699 return PTR_ERR(info);
700
701 if (!info->opps)
702 return -EIO;
703
704 for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
705 ret = dev_pm_opp_add(dev, opp->freq, opp->m_volt * 1000);
706 if (ret) {
707 dev_warn(dev, "failed to add opp %uHz %umV\n",
708 opp->freq, opp->m_volt);
709 while (idx-- > 0)
710 dev_pm_opp_remove(dev, (--opp)->freq);
711 return ret;
712 }
713 }
714 return 0;
715 }
716
scpi_sensor_get_capability(u16 * sensors)717 static int scpi_sensor_get_capability(u16 *sensors)
718 {
719 __le16 cap;
720 int ret;
721
722 ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap,
723 sizeof(cap));
724 if (!ret)
725 *sensors = le16_to_cpu(cap);
726
727 return ret;
728 }
729
scpi_sensor_get_info(u16 sensor_id,struct scpi_sensor_info * info)730 static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
731 {
732 __le16 id = cpu_to_le16(sensor_id);
733 struct _scpi_sensor_info _info;
734 int ret;
735
736 ret = scpi_send_message(CMD_SENSOR_INFO, &id, sizeof(id),
737 &_info, sizeof(_info));
738 if (!ret) {
739 memcpy(info, &_info, sizeof(*info));
740 info->sensor_id = le16_to_cpu(_info.sensor_id);
741 }
742
743 return ret;
744 }
745
scpi_sensor_get_value(u16 sensor,u64 * val)746 static int scpi_sensor_get_value(u16 sensor, u64 *val)
747 {
748 __le16 id = cpu_to_le16(sensor);
749 __le64 value;
750 int ret;
751
752 ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
753 &value, sizeof(value));
754 if (ret)
755 return ret;
756
757 if (scpi_info->is_legacy)
758 /* only 32-bits supported, upper 32 bits can be junk */
759 *val = le32_to_cpup((__le32 *)&value);
760 else
761 *val = le64_to_cpu(value);
762
763 return 0;
764 }
765
scpi_device_get_power_state(u16 dev_id)766 static int scpi_device_get_power_state(u16 dev_id)
767 {
768 int ret;
769 u8 pstate;
770 __le16 id = cpu_to_le16(dev_id);
771
772 ret = scpi_send_message(CMD_GET_DEVICE_PWR_STATE, &id,
773 sizeof(id), &pstate, sizeof(pstate));
774 return ret ? ret : pstate;
775 }
776
scpi_device_set_power_state(u16 dev_id,u8 pstate)777 static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
778 {
779 int stat;
780 struct dev_pstate_set dev_set = {
781 .dev_id = cpu_to_le16(dev_id),
782 .pstate = pstate,
783 };
784
785 return scpi_send_message(CMD_SET_DEVICE_PWR_STATE, &dev_set,
786 sizeof(dev_set), &stat, sizeof(stat));
787 }
788
789 static struct scpi_ops scpi_ops = {
790 .get_version = scpi_get_version,
791 .clk_get_range = scpi_clk_get_range,
792 .clk_get_val = scpi_clk_get_val,
793 .clk_set_val = scpi_clk_set_val,
794 .dvfs_get_idx = scpi_dvfs_get_idx,
795 .dvfs_set_idx = scpi_dvfs_set_idx,
796 .dvfs_get_info = scpi_dvfs_get_info,
797 .device_domain_id = scpi_dev_domain_id,
798 .get_transition_latency = scpi_dvfs_get_transition_latency,
799 .add_opps_to_device = scpi_dvfs_add_opps_to_device,
800 .sensor_get_capability = scpi_sensor_get_capability,
801 .sensor_get_info = scpi_sensor_get_info,
802 .sensor_get_value = scpi_sensor_get_value,
803 .device_get_power_state = scpi_device_get_power_state,
804 .device_set_power_state = scpi_device_set_power_state,
805 };
806
get_scpi_ops(void)807 struct scpi_ops *get_scpi_ops(void)
808 {
809 return scpi_info ? scpi_info->scpi_ops : NULL;
810 }
811 EXPORT_SYMBOL_GPL(get_scpi_ops);
812
scpi_init_versions(struct scpi_drvinfo * info)813 static int scpi_init_versions(struct scpi_drvinfo *info)
814 {
815 int ret;
816 struct scp_capabilities caps;
817
818 ret = scpi_send_message(CMD_SCPI_CAPABILITIES, NULL, 0,
819 &caps, sizeof(caps));
820 if (!ret) {
821 info->protocol_version = le32_to_cpu(caps.protocol_version);
822 info->firmware_version = le32_to_cpu(caps.platform_version);
823 }
824 /* Ignore error if not implemented */
825 if (info->is_legacy && ret == -EOPNOTSUPP)
826 return 0;
827
828 return ret;
829 }
830
protocol_version_show(struct device * dev,struct device_attribute * attr,char * buf)831 static ssize_t protocol_version_show(struct device *dev,
832 struct device_attribute *attr, char *buf)
833 {
834 struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
835
836 return sprintf(buf, "%lu.%lu\n",
837 FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
838 FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
839 }
840 static DEVICE_ATTR_RO(protocol_version);
841
firmware_version_show(struct device * dev,struct device_attribute * attr,char * buf)842 static ssize_t firmware_version_show(struct device *dev,
843 struct device_attribute *attr, char *buf)
844 {
845 struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
846
847 return sprintf(buf, "%lu.%lu.%lu\n",
848 FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
849 FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
850 FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
851 }
852 static DEVICE_ATTR_RO(firmware_version);
853
854 static struct attribute *versions_attrs[] = {
855 &dev_attr_firmware_version.attr,
856 &dev_attr_protocol_version.attr,
857 NULL,
858 };
859 ATTRIBUTE_GROUPS(versions);
860
scpi_free_channels(void * data)861 static void scpi_free_channels(void *data)
862 {
863 struct scpi_drvinfo *info = data;
864 int i;
865
866 for (i = 0; i < info->num_chans; i++)
867 mbox_free_channel(info->channels[i].chan);
868 }
869
scpi_remove(struct platform_device * pdev)870 static void scpi_remove(struct platform_device *pdev)
871 {
872 int i;
873 struct scpi_drvinfo *info = platform_get_drvdata(pdev);
874
875 scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
876
877 for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
878 kfree(info->dvfs[i]->opps);
879 kfree(info->dvfs[i]);
880 }
881 }
882
883 #define MAX_SCPI_XFERS 10
scpi_alloc_xfer_list(struct device * dev,struct scpi_chan * ch)884 static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
885 {
886 int i;
887 struct scpi_xfer *xfers;
888
889 xfers = devm_kcalloc(dev, MAX_SCPI_XFERS, sizeof(*xfers), GFP_KERNEL);
890 if (!xfers)
891 return -ENOMEM;
892
893 ch->xfers = xfers;
894 for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++) {
895 init_completion(&xfers->done);
896 list_add_tail(&xfers->node, &ch->xfers_list);
897 }
898
899 return 0;
900 }
901
902 static const struct of_device_id shmem_of_match[] __maybe_unused = {
903 { .compatible = "amlogic,meson-gxbb-scp-shmem", },
904 { .compatible = "amlogic,meson-axg-scp-shmem", },
905 { .compatible = "arm,juno-scp-shmem", },
906 { .compatible = "arm,scp-shmem", },
907 { }
908 };
909
scpi_probe(struct platform_device * pdev)910 static int scpi_probe(struct platform_device *pdev)
911 {
912 int count, idx, ret;
913 struct resource res;
914 struct device *dev = &pdev->dev;
915 struct device_node *np = dev->of_node;
916 struct scpi_drvinfo *scpi_drvinfo;
917
918 scpi_drvinfo = devm_kzalloc(dev, sizeof(*scpi_drvinfo), GFP_KERNEL);
919 if (!scpi_drvinfo)
920 return -ENOMEM;
921
922 scpi_drvinfo->is_legacy = !!device_get_match_data(dev);
923
924 count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
925 if (count < 0) {
926 dev_err(dev, "no mboxes property in '%pOF'\n", np);
927 return -ENODEV;
928 }
929
930 scpi_drvinfo->channels =
931 devm_kcalloc(dev, count, sizeof(struct scpi_chan), GFP_KERNEL);
932 if (!scpi_drvinfo->channels)
933 return -ENOMEM;
934
935 ret = devm_add_action(dev, scpi_free_channels, scpi_drvinfo);
936 if (ret)
937 return ret;
938
939 for (; scpi_drvinfo->num_chans < count; scpi_drvinfo->num_chans++) {
940 resource_size_t size;
941 int idx = scpi_drvinfo->num_chans;
942 struct scpi_chan *pchan = scpi_drvinfo->channels + idx;
943 struct mbox_client *cl = &pchan->cl;
944 struct device_node *shmem __free(device_node) =
945 of_parse_phandle(np, "shmem", idx);
946
947 if (!of_match_node(shmem_of_match, shmem))
948 return -ENXIO;
949
950 ret = of_address_to_resource(shmem, 0, &res);
951 if (ret) {
952 dev_err(dev, "failed to get SCPI payload mem resource\n");
953 return ret;
954 }
955
956 size = resource_size(&res);
957 pchan->rx_payload = devm_ioremap(dev, res.start, size);
958 if (!pchan->rx_payload) {
959 dev_err(dev, "failed to ioremap SCPI payload\n");
960 return -EADDRNOTAVAIL;
961 }
962 pchan->tx_payload = pchan->rx_payload + (size >> 1);
963
964 cl->dev = dev;
965 cl->rx_callback = scpi_handle_remote_msg;
966 cl->tx_prepare = scpi_tx_prepare;
967 cl->tx_block = true;
968 cl->tx_tout = 20;
969 cl->knows_txdone = false; /* controller can't ack */
970
971 INIT_LIST_HEAD(&pchan->rx_pending);
972 INIT_LIST_HEAD(&pchan->xfers_list);
973 spin_lock_init(&pchan->rx_lock);
974 mutex_init(&pchan->xfers_lock);
975
976 ret = scpi_alloc_xfer_list(dev, pchan);
977 if (!ret) {
978 pchan->chan = mbox_request_channel(cl, idx);
979 if (!IS_ERR(pchan->chan))
980 continue;
981 ret = PTR_ERR(pchan->chan);
982 if (ret != -EPROBE_DEFER)
983 dev_err(dev, "failed to get channel%d err %d\n",
984 idx, ret);
985 }
986 return ret;
987 }
988
989 scpi_drvinfo->commands = scpi_std_commands;
990
991 platform_set_drvdata(pdev, scpi_drvinfo);
992
993 if (scpi_drvinfo->is_legacy) {
994 /* Replace with legacy variants */
995 scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
996 scpi_drvinfo->commands = scpi_legacy_commands;
997
998 /* Fill priority bitmap */
999 for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
1000 set_bit(legacy_hpriority_cmds[idx],
1001 scpi_drvinfo->cmd_priority);
1002 }
1003
1004 scpi_info = scpi_drvinfo;
1005
1006 ret = scpi_init_versions(scpi_drvinfo);
1007 if (ret) {
1008 dev_err(dev, "incorrect or no SCP firmware found\n");
1009 scpi_info = NULL;
1010 return ret;
1011 }
1012
1013 if (scpi_drvinfo->is_legacy && !scpi_drvinfo->protocol_version &&
1014 !scpi_drvinfo->firmware_version)
1015 dev_info(dev, "SCP Protocol legacy pre-1.0 firmware\n");
1016 else
1017 dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
1018 FIELD_GET(PROTO_REV_MAJOR_MASK,
1019 scpi_drvinfo->protocol_version),
1020 FIELD_GET(PROTO_REV_MINOR_MASK,
1021 scpi_drvinfo->protocol_version),
1022 FIELD_GET(FW_REV_MAJOR_MASK,
1023 scpi_drvinfo->firmware_version),
1024 FIELD_GET(FW_REV_MINOR_MASK,
1025 scpi_drvinfo->firmware_version),
1026 FIELD_GET(FW_REV_PATCH_MASK,
1027 scpi_drvinfo->firmware_version));
1028
1029 scpi_drvinfo->scpi_ops = &scpi_ops;
1030
1031 ret = devm_of_platform_populate(dev);
1032 if (ret)
1033 scpi_info = NULL;
1034
1035 return ret;
1036 }
1037
1038 static const struct of_device_id scpi_of_match[] = {
1039 {.compatible = "arm,scpi"},
1040 {.compatible = "arm,scpi-pre-1.0", .data = (void *)1UL },
1041 {},
1042 };
1043
1044 MODULE_DEVICE_TABLE(of, scpi_of_match);
1045
1046 static struct platform_driver scpi_driver = {
1047 .driver = {
1048 .name = "scpi_protocol",
1049 .of_match_table = scpi_of_match,
1050 .dev_groups = versions_groups,
1051 },
1052 .probe = scpi_probe,
1053 .remove = scpi_remove,
1054 };
1055 module_platform_driver(scpi_driver);
1056
1057 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1058 MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1059 MODULE_LICENSE("GPL v2");
1060