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