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