1 /*
2 * System Control and Power Interface (SCPI) Message Protocol driver
3 *
4 * SCPI Message Protocol is used between the System Control Processor(SCP)
5 * and the Application Processors(AP). The Message Handling Unit(MHU)
6 * provides a mechanism for inter-processor communication between SCP's
7 * Cortex M3 and AP.
8 *
9 * SCP offers control and management of the core/cluster power states,
10 * various power domain DVFS including the core/cluster, certain system
11 * clocks configuration, thermal sensors and many others.
12 *
13 * Copyright (C) 2015 ARM Ltd.
14 *
15 * This program is free software; you can redistribute it and/or modify it
16 * under the terms and conditions of the GNU General Public License,
17 * version 2, as published by the Free Software Foundation.
18 *
19 * This program is distributed in the hope it will be useful, but WITHOUT
20 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
21 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
22 * more details.
23 *
24 * You should have received a copy of the GNU General Public License along
25 * with this program. If not, see <http://www.gnu.org/licenses/>.
26 */
27
28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29
30 #include <linux/bitmap.h>
31 #include <linux/bitfield.h>
32 #include <linux/device.h>
33 #include <linux/err.h>
34 #include <linux/export.h>
35 #include <linux/io.h>
36 #include <linux/kernel.h>
37 #include <linux/list.h>
38 #include <linux/mailbox_client.h>
39 #include <linux/module.h>
40 #include <linux/of_address.h>
41 #include <linux/of_platform.h>
42 #include <linux/printk.h>
43 #include <linux/pm_opp.h>
44 #include <linux/scpi_protocol.h>
45 #include <linux/slab.h>
46 #include <linux/sort.h>
47 #include <linux/spinlock.h>
48
49 #define CMD_ID_MASK GENMASK(6, 0)
50 #define CMD_TOKEN_ID_MASK GENMASK(15, 8)
51 #define CMD_DATA_SIZE_MASK GENMASK(24, 16)
52 #define CMD_LEGACY_DATA_SIZE_MASK GENMASK(28, 20)
53 #define PACK_SCPI_CMD(cmd_id, tx_sz) \
54 (FIELD_PREP(CMD_ID_MASK, cmd_id) | \
55 FIELD_PREP(CMD_DATA_SIZE_MASK, tx_sz))
56 #define PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz) \
57 (FIELD_PREP(CMD_ID_MASK, cmd_id) | \
58 FIELD_PREP(CMD_LEGACY_DATA_SIZE_MASK, tx_sz))
59
60 #define CMD_SIZE(cmd) FIELD_GET(CMD_DATA_SIZE_MASK, cmd)
61 #define CMD_UNIQ_MASK (CMD_TOKEN_ID_MASK | CMD_ID_MASK)
62 #define CMD_XTRACT_UNIQ(cmd) ((cmd) & CMD_UNIQ_MASK)
63
64 #define SCPI_SLOT 0
65
66 #define MAX_DVFS_DOMAINS 8
67 #define MAX_DVFS_OPPS 16
68
69 #define PROTO_REV_MAJOR_MASK GENMASK(31, 16)
70 #define PROTO_REV_MINOR_MASK GENMASK(15, 0)
71
72 #define FW_REV_MAJOR_MASK GENMASK(31, 24)
73 #define FW_REV_MINOR_MASK GENMASK(23, 16)
74 #define FW_REV_PATCH_MASK GENMASK(15, 0)
75
76 #define MAX_RX_TIMEOUT (msecs_to_jiffies(30))
77
78 enum scpi_error_codes {
79 SCPI_SUCCESS = 0, /* Success */
80 SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
81 SCPI_ERR_ALIGN = 2, /* Invalid alignment */
82 SCPI_ERR_SIZE = 3, /* Invalid size */
83 SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
84 SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
85 SCPI_ERR_RANGE = 6, /* Value out of range */
86 SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
87 SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
88 SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
89 SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
90 SCPI_ERR_DEVICE = 11, /* Device error */
91 SCPI_ERR_BUSY = 12, /* Device busy */
92 SCPI_ERR_MAX
93 };
94
95 /* SCPI Standard commands */
96 enum scpi_std_cmd {
97 SCPI_CMD_INVALID = 0x00,
98 SCPI_CMD_SCPI_READY = 0x01,
99 SCPI_CMD_SCPI_CAPABILITIES = 0x02,
100 SCPI_CMD_SET_CSS_PWR_STATE = 0x03,
101 SCPI_CMD_GET_CSS_PWR_STATE = 0x04,
102 SCPI_CMD_SET_SYS_PWR_STATE = 0x05,
103 SCPI_CMD_SET_CPU_TIMER = 0x06,
104 SCPI_CMD_CANCEL_CPU_TIMER = 0x07,
105 SCPI_CMD_DVFS_CAPABILITIES = 0x08,
106 SCPI_CMD_GET_DVFS_INFO = 0x09,
107 SCPI_CMD_SET_DVFS = 0x0a,
108 SCPI_CMD_GET_DVFS = 0x0b,
109 SCPI_CMD_GET_DVFS_STAT = 0x0c,
110 SCPI_CMD_CLOCK_CAPABILITIES = 0x0d,
111 SCPI_CMD_GET_CLOCK_INFO = 0x0e,
112 SCPI_CMD_SET_CLOCK_VALUE = 0x0f,
113 SCPI_CMD_GET_CLOCK_VALUE = 0x10,
114 SCPI_CMD_PSU_CAPABILITIES = 0x11,
115 SCPI_CMD_GET_PSU_INFO = 0x12,
116 SCPI_CMD_SET_PSU = 0x13,
117 SCPI_CMD_GET_PSU = 0x14,
118 SCPI_CMD_SENSOR_CAPABILITIES = 0x15,
119 SCPI_CMD_SENSOR_INFO = 0x16,
120 SCPI_CMD_SENSOR_VALUE = 0x17,
121 SCPI_CMD_SENSOR_CFG_PERIODIC = 0x18,
122 SCPI_CMD_SENSOR_CFG_BOUNDS = 0x19,
123 SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1a,
124 SCPI_CMD_SET_DEVICE_PWR_STATE = 0x1b,
125 SCPI_CMD_GET_DEVICE_PWR_STATE = 0x1c,
126 SCPI_CMD_COUNT
127 };
128
129 /* SCPI Legacy Commands */
130 enum legacy_scpi_std_cmd {
131 LEGACY_SCPI_CMD_INVALID = 0x00,
132 LEGACY_SCPI_CMD_SCPI_READY = 0x01,
133 LEGACY_SCPI_CMD_SCPI_CAPABILITIES = 0x02,
134 LEGACY_SCPI_CMD_EVENT = 0x03,
135 LEGACY_SCPI_CMD_SET_CSS_PWR_STATE = 0x04,
136 LEGACY_SCPI_CMD_GET_CSS_PWR_STATE = 0x05,
137 LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT = 0x06,
138 LEGACY_SCPI_CMD_GET_PWR_STATE_STAT = 0x07,
139 LEGACY_SCPI_CMD_SYS_PWR_STATE = 0x08,
140 LEGACY_SCPI_CMD_L2_READY = 0x09,
141 LEGACY_SCPI_CMD_SET_AP_TIMER = 0x0a,
142 LEGACY_SCPI_CMD_CANCEL_AP_TIME = 0x0b,
143 LEGACY_SCPI_CMD_DVFS_CAPABILITIES = 0x0c,
144 LEGACY_SCPI_CMD_GET_DVFS_INFO = 0x0d,
145 LEGACY_SCPI_CMD_SET_DVFS = 0x0e,
146 LEGACY_SCPI_CMD_GET_DVFS = 0x0f,
147 LEGACY_SCPI_CMD_GET_DVFS_STAT = 0x10,
148 LEGACY_SCPI_CMD_SET_RTC = 0x11,
149 LEGACY_SCPI_CMD_GET_RTC = 0x12,
150 LEGACY_SCPI_CMD_CLOCK_CAPABILITIES = 0x13,
151 LEGACY_SCPI_CMD_SET_CLOCK_INDEX = 0x14,
152 LEGACY_SCPI_CMD_SET_CLOCK_VALUE = 0x15,
153 LEGACY_SCPI_CMD_GET_CLOCK_VALUE = 0x16,
154 LEGACY_SCPI_CMD_PSU_CAPABILITIES = 0x17,
155 LEGACY_SCPI_CMD_SET_PSU = 0x18,
156 LEGACY_SCPI_CMD_GET_PSU = 0x19,
157 LEGACY_SCPI_CMD_SENSOR_CAPABILITIES = 0x1a,
158 LEGACY_SCPI_CMD_SENSOR_INFO = 0x1b,
159 LEGACY_SCPI_CMD_SENSOR_VALUE = 0x1c,
160 LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC = 0x1d,
161 LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS = 0x1e,
162 LEGACY_SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1f,
163 LEGACY_SCPI_CMD_COUNT
164 };
165
166 /* List all commands that are required to go through the high priority link */
167 static int legacy_hpriority_cmds[] = {
168 LEGACY_SCPI_CMD_GET_CSS_PWR_STATE,
169 LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT,
170 LEGACY_SCPI_CMD_GET_PWR_STATE_STAT,
171 LEGACY_SCPI_CMD_SET_DVFS,
172 LEGACY_SCPI_CMD_GET_DVFS,
173 LEGACY_SCPI_CMD_SET_RTC,
174 LEGACY_SCPI_CMD_GET_RTC,
175 LEGACY_SCPI_CMD_SET_CLOCK_INDEX,
176 LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
177 LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
178 LEGACY_SCPI_CMD_SET_PSU,
179 LEGACY_SCPI_CMD_GET_PSU,
180 LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC,
181 LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS,
182 };
183
184 /* List all commands used by this driver, used as indexes */
185 enum scpi_drv_cmds {
186 CMD_SCPI_CAPABILITIES = 0,
187 CMD_GET_CLOCK_INFO,
188 CMD_GET_CLOCK_VALUE,
189 CMD_SET_CLOCK_VALUE,
190 CMD_GET_DVFS,
191 CMD_SET_DVFS,
192 CMD_GET_DVFS_INFO,
193 CMD_SENSOR_CAPABILITIES,
194 CMD_SENSOR_INFO,
195 CMD_SENSOR_VALUE,
196 CMD_SET_DEVICE_PWR_STATE,
197 CMD_GET_DEVICE_PWR_STATE,
198 CMD_MAX_COUNT,
199 };
200
201 static int scpi_std_commands[CMD_MAX_COUNT] = {
202 SCPI_CMD_SCPI_CAPABILITIES,
203 SCPI_CMD_GET_CLOCK_INFO,
204 SCPI_CMD_GET_CLOCK_VALUE,
205 SCPI_CMD_SET_CLOCK_VALUE,
206 SCPI_CMD_GET_DVFS,
207 SCPI_CMD_SET_DVFS,
208 SCPI_CMD_GET_DVFS_INFO,
209 SCPI_CMD_SENSOR_CAPABILITIES,
210 SCPI_CMD_SENSOR_INFO,
211 SCPI_CMD_SENSOR_VALUE,
212 SCPI_CMD_SET_DEVICE_PWR_STATE,
213 SCPI_CMD_GET_DEVICE_PWR_STATE,
214 };
215
216 static int scpi_legacy_commands[CMD_MAX_COUNT] = {
217 LEGACY_SCPI_CMD_SCPI_CAPABILITIES,
218 -1, /* GET_CLOCK_INFO */
219 LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
220 LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
221 LEGACY_SCPI_CMD_GET_DVFS,
222 LEGACY_SCPI_CMD_SET_DVFS,
223 LEGACY_SCPI_CMD_GET_DVFS_INFO,
224 LEGACY_SCPI_CMD_SENSOR_CAPABILITIES,
225 LEGACY_SCPI_CMD_SENSOR_INFO,
226 LEGACY_SCPI_CMD_SENSOR_VALUE,
227 -1, /* SET_DEVICE_PWR_STATE */
228 -1, /* GET_DEVICE_PWR_STATE */
229 };
230
231 struct scpi_xfer {
232 u32 slot; /* has to be first element */
233 u32 cmd;
234 u32 status;
235 const void *tx_buf;
236 void *rx_buf;
237 unsigned int tx_len;
238 unsigned int rx_len;
239 struct list_head node;
240 struct completion done;
241 };
242
243 struct scpi_chan {
244 struct mbox_client cl;
245 struct mbox_chan *chan;
246 void __iomem *tx_payload;
247 void __iomem *rx_payload;
248 struct list_head rx_pending;
249 struct list_head xfers_list;
250 struct scpi_xfer *xfers;
251 spinlock_t rx_lock; /* locking for the rx pending list */
252 struct mutex xfers_lock;
253 u8 token;
254 };
255
256 struct scpi_drvinfo {
257 u32 protocol_version;
258 u32 firmware_version;
259 bool is_legacy;
260 int num_chans;
261 int *commands;
262 DECLARE_BITMAP(cmd_priority, LEGACY_SCPI_CMD_COUNT);
263 atomic_t next_chan;
264 struct scpi_ops *scpi_ops;
265 struct scpi_chan *channels;
266 struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
267 };
268
269 /*
270 * The SCP firmware only executes in little-endian mode, so any buffers
271 * shared through SCPI should have their contents converted to little-endian
272 */
273 struct scpi_shared_mem {
274 __le32 command;
275 __le32 status;
276 u8 payload[0];
277 } __packed;
278
279 struct legacy_scpi_shared_mem {
280 __le32 status;
281 u8 payload[0];
282 } __packed;
283
284 struct scp_capabilities {
285 __le32 protocol_version;
286 __le32 event_version;
287 __le32 platform_version;
288 __le32 commands[4];
289 } __packed;
290
291 struct clk_get_info {
292 __le16 id;
293 __le16 flags;
294 __le32 min_rate;
295 __le32 max_rate;
296 u8 name[20];
297 } __packed;
298
299 struct clk_set_value {
300 __le16 id;
301 __le16 reserved;
302 __le32 rate;
303 } __packed;
304
305 struct legacy_clk_set_value {
306 __le32 rate;
307 __le16 id;
308 __le16 reserved;
309 } __packed;
310
311 struct dvfs_info {
312 u8 domain;
313 u8 opp_count;
314 __le16 latency;
315 struct {
316 __le32 freq;
317 __le32 m_volt;
318 } opps[MAX_DVFS_OPPS];
319 } __packed;
320
321 struct dvfs_set {
322 u8 domain;
323 u8 index;
324 } __packed;
325
326 struct _scpi_sensor_info {
327 __le16 sensor_id;
328 u8 class;
329 u8 trigger_type;
330 char name[20];
331 };
332
333 struct dev_pstate_set {
334 __le16 dev_id;
335 u8 pstate;
336 } __packed;
337
338 static struct scpi_drvinfo *scpi_info;
339
340 static int scpi_linux_errmap[SCPI_ERR_MAX] = {
341 /* better than switch case as long as return value is continuous */
342 0, /* SCPI_SUCCESS */
343 -EINVAL, /* SCPI_ERR_PARAM */
344 -ENOEXEC, /* SCPI_ERR_ALIGN */
345 -EMSGSIZE, /* SCPI_ERR_SIZE */
346 -EINVAL, /* SCPI_ERR_HANDLER */
347 -EACCES, /* SCPI_ERR_ACCESS */
348 -ERANGE, /* SCPI_ERR_RANGE */
349 -ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
350 -ENOMEM, /* SCPI_ERR_NOMEM */
351 -EINVAL, /* SCPI_ERR_PWRSTATE */
352 -EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
353 -EIO, /* SCPI_ERR_DEVICE */
354 -EBUSY, /* SCPI_ERR_BUSY */
355 };
356
scpi_to_linux_errno(int errno)357 static inline int scpi_to_linux_errno(int errno)
358 {
359 if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
360 return scpi_linux_errmap[errno];
361 return -EIO;
362 }
363
scpi_process_cmd(struct scpi_chan * ch,u32 cmd)364 static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
365 {
366 unsigned long flags;
367 struct scpi_xfer *t, *match = NULL;
368
369 spin_lock_irqsave(&ch->rx_lock, flags);
370 if (list_empty(&ch->rx_pending)) {
371 spin_unlock_irqrestore(&ch->rx_lock, flags);
372 return;
373 }
374
375 /* Command type is not replied by the SCP Firmware in legacy Mode
376 * We should consider that command is the head of pending RX commands
377 * if the list is not empty. In TX only mode, the list would be empty.
378 */
379 if (scpi_info->is_legacy) {
380 match = list_first_entry(&ch->rx_pending, struct scpi_xfer,
381 node);
382 list_del(&match->node);
383 } else {
384 list_for_each_entry(t, &ch->rx_pending, node)
385 if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
386 list_del(&t->node);
387 match = t;
388 break;
389 }
390 }
391 /* check if wait_for_completion is in progress or timed-out */
392 if (match && !completion_done(&match->done)) {
393 unsigned int len;
394
395 if (scpi_info->is_legacy) {
396 struct legacy_scpi_shared_mem __iomem *mem =
397 ch->rx_payload;
398
399 /* RX Length is not replied by the legacy Firmware */
400 len = match->rx_len;
401
402 match->status = ioread32(&mem->status);
403 memcpy_fromio(match->rx_buf, mem->payload, len);
404 } else {
405 struct scpi_shared_mem __iomem *mem = ch->rx_payload;
406
407 len = min_t(unsigned int, match->rx_len, CMD_SIZE(cmd));
408
409 match->status = ioread32(&mem->status);
410 memcpy_fromio(match->rx_buf, mem->payload, len);
411 }
412
413 if (match->rx_len > len)
414 memset(match->rx_buf + len, 0, match->rx_len - len);
415 complete(&match->done);
416 }
417 spin_unlock_irqrestore(&ch->rx_lock, flags);
418 }
419
scpi_handle_remote_msg(struct mbox_client * c,void * msg)420 static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
421 {
422 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
423 struct scpi_shared_mem __iomem *mem = ch->rx_payload;
424 u32 cmd = 0;
425
426 if (!scpi_info->is_legacy)
427 cmd = ioread32(&mem->command);
428
429 scpi_process_cmd(ch, cmd);
430 }
431
scpi_tx_prepare(struct mbox_client * c,void * msg)432 static void scpi_tx_prepare(struct mbox_client *c, void *msg)
433 {
434 unsigned long flags;
435 struct scpi_xfer *t = msg;
436 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
437 struct scpi_shared_mem __iomem *mem = ch->tx_payload;
438
439 if (t->tx_buf) {
440 if (scpi_info->is_legacy)
441 memcpy_toio(ch->tx_payload, t->tx_buf, t->tx_len);
442 else
443 memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
444 }
445
446 if (t->rx_buf) {
447 if (!(++ch->token))
448 ++ch->token;
449 t->cmd |= FIELD_PREP(CMD_TOKEN_ID_MASK, ch->token);
450 spin_lock_irqsave(&ch->rx_lock, flags);
451 list_add_tail(&t->node, &ch->rx_pending);
452 spin_unlock_irqrestore(&ch->rx_lock, flags);
453 }
454
455 if (!scpi_info->is_legacy)
456 iowrite32(t->cmd, &mem->command);
457 }
458
get_scpi_xfer(struct scpi_chan * ch)459 static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
460 {
461 struct scpi_xfer *t;
462
463 mutex_lock(&ch->xfers_lock);
464 if (list_empty(&ch->xfers_list)) {
465 mutex_unlock(&ch->xfers_lock);
466 return NULL;
467 }
468 t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
469 list_del(&t->node);
470 mutex_unlock(&ch->xfers_lock);
471 return t;
472 }
473
put_scpi_xfer(struct scpi_xfer * t,struct scpi_chan * ch)474 static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
475 {
476 mutex_lock(&ch->xfers_lock);
477 list_add_tail(&t->node, &ch->xfers_list);
478 mutex_unlock(&ch->xfers_lock);
479 }
480
scpi_send_message(u8 idx,void * tx_buf,unsigned int tx_len,void * rx_buf,unsigned int rx_len)481 static int scpi_send_message(u8 idx, void *tx_buf, unsigned int tx_len,
482 void *rx_buf, unsigned int rx_len)
483 {
484 int ret;
485 u8 chan;
486 u8 cmd;
487 struct scpi_xfer *msg;
488 struct scpi_chan *scpi_chan;
489
490 if (scpi_info->commands[idx] < 0)
491 return -EOPNOTSUPP;
492
493 cmd = scpi_info->commands[idx];
494
495 if (scpi_info->is_legacy)
496 chan = test_bit(cmd, scpi_info->cmd_priority) ? 1 : 0;
497 else
498 chan = atomic_inc_return(&scpi_info->next_chan) %
499 scpi_info->num_chans;
500 scpi_chan = scpi_info->channels + chan;
501
502 msg = get_scpi_xfer(scpi_chan);
503 if (!msg)
504 return -ENOMEM;
505
506 if (scpi_info->is_legacy) {
507 msg->cmd = PACK_LEGACY_SCPI_CMD(cmd, tx_len);
508 msg->slot = msg->cmd;
509 } else {
510 msg->slot = BIT(SCPI_SLOT);
511 msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
512 }
513 msg->tx_buf = tx_buf;
514 msg->tx_len = tx_len;
515 msg->rx_buf = rx_buf;
516 msg->rx_len = rx_len;
517 reinit_completion(&msg->done);
518
519 ret = mbox_send_message(scpi_chan->chan, msg);
520 if (ret < 0 || !rx_buf)
521 goto out;
522
523 if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
524 ret = -ETIMEDOUT;
525 else
526 /* first status word */
527 ret = msg->status;
528 out:
529 if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
530 scpi_process_cmd(scpi_chan, msg->cmd);
531
532 put_scpi_xfer(msg, scpi_chan);
533 /* SCPI error codes > 0, translate them to Linux scale*/
534 return ret > 0 ? scpi_to_linux_errno(ret) : ret;
535 }
536
scpi_get_version(void)537 static u32 scpi_get_version(void)
538 {
539 return scpi_info->protocol_version;
540 }
541
542 static int
scpi_clk_get_range(u16 clk_id,unsigned long * min,unsigned long * max)543 scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
544 {
545 int ret;
546 struct clk_get_info clk;
547 __le16 le_clk_id = cpu_to_le16(clk_id);
548
549 ret = scpi_send_message(CMD_GET_CLOCK_INFO, &le_clk_id,
550 sizeof(le_clk_id), &clk, sizeof(clk));
551 if (!ret) {
552 *min = le32_to_cpu(clk.min_rate);
553 *max = le32_to_cpu(clk.max_rate);
554 }
555 return ret;
556 }
557
scpi_clk_get_val(u16 clk_id)558 static unsigned long scpi_clk_get_val(u16 clk_id)
559 {
560 int ret;
561 __le32 rate;
562 __le16 le_clk_id = cpu_to_le16(clk_id);
563
564 ret = scpi_send_message(CMD_GET_CLOCK_VALUE, &le_clk_id,
565 sizeof(le_clk_id), &rate, sizeof(rate));
566
567 return ret ? ret : le32_to_cpu(rate);
568 }
569
scpi_clk_set_val(u16 clk_id,unsigned long rate)570 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
571 {
572 int stat;
573 struct clk_set_value clk = {
574 .id = cpu_to_le16(clk_id),
575 .rate = cpu_to_le32(rate)
576 };
577
578 return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
579 &stat, sizeof(stat));
580 }
581
legacy_scpi_clk_set_val(u16 clk_id,unsigned long rate)582 static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
583 {
584 int stat;
585 struct legacy_clk_set_value clk = {
586 .id = cpu_to_le16(clk_id),
587 .rate = cpu_to_le32(rate)
588 };
589
590 return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
591 &stat, sizeof(stat));
592 }
593
scpi_dvfs_get_idx(u8 domain)594 static int scpi_dvfs_get_idx(u8 domain)
595 {
596 int ret;
597 u8 dvfs_idx;
598
599 ret = scpi_send_message(CMD_GET_DVFS, &domain, sizeof(domain),
600 &dvfs_idx, sizeof(dvfs_idx));
601
602 return ret ? ret : dvfs_idx;
603 }
604
scpi_dvfs_set_idx(u8 domain,u8 index)605 static int scpi_dvfs_set_idx(u8 domain, u8 index)
606 {
607 int stat;
608 struct dvfs_set dvfs = {domain, index};
609
610 return scpi_send_message(CMD_SET_DVFS, &dvfs, sizeof(dvfs),
611 &stat, sizeof(stat));
612 }
613
opp_cmp_func(const void * opp1,const void * opp2)614 static int opp_cmp_func(const void *opp1, const void *opp2)
615 {
616 const struct scpi_opp *t1 = opp1, *t2 = opp2;
617
618 return t1->freq - t2->freq;
619 }
620
scpi_dvfs_get_info(u8 domain)621 static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
622 {
623 struct scpi_dvfs_info *info;
624 struct scpi_opp *opp;
625 struct dvfs_info buf;
626 int ret, i;
627
628 if (domain >= MAX_DVFS_DOMAINS)
629 return ERR_PTR(-EINVAL);
630
631 if (scpi_info->dvfs[domain]) /* data already populated */
632 return scpi_info->dvfs[domain];
633
634 ret = scpi_send_message(CMD_GET_DVFS_INFO, &domain, sizeof(domain),
635 &buf, sizeof(buf));
636 if (ret)
637 return ERR_PTR(ret);
638
639 info = kmalloc(sizeof(*info), GFP_KERNEL);
640 if (!info)
641 return ERR_PTR(-ENOMEM);
642
643 info->count = buf.opp_count;
644 info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
645
646 info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
647 if (!info->opps) {
648 kfree(info);
649 return ERR_PTR(-ENOMEM);
650 }
651
652 for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
653 opp->freq = le32_to_cpu(buf.opps[i].freq);
654 opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
655 }
656
657 sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
658
659 scpi_info->dvfs[domain] = info;
660 return info;
661 }
662
scpi_dev_domain_id(struct device * dev)663 static int scpi_dev_domain_id(struct device *dev)
664 {
665 struct of_phandle_args clkspec;
666
667 if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
668 0, &clkspec))
669 return -EINVAL;
670
671 return clkspec.args[0];
672 }
673
scpi_dvfs_info(struct device * dev)674 static struct scpi_dvfs_info *scpi_dvfs_info(struct device *dev)
675 {
676 int domain = scpi_dev_domain_id(dev);
677
678 if (domain < 0)
679 return ERR_PTR(domain);
680
681 return scpi_dvfs_get_info(domain);
682 }
683
scpi_dvfs_get_transition_latency(struct device * dev)684 static int scpi_dvfs_get_transition_latency(struct device *dev)
685 {
686 struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
687
688 if (IS_ERR(info))
689 return PTR_ERR(info);
690
691 return info->latency;
692 }
693
scpi_dvfs_add_opps_to_device(struct device * dev)694 static int scpi_dvfs_add_opps_to_device(struct device *dev)
695 {
696 int idx, ret;
697 struct scpi_opp *opp;
698 struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
699
700 if (IS_ERR(info))
701 return PTR_ERR(info);
702
703 if (!info->opps)
704 return -EIO;
705
706 for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
707 ret = dev_pm_opp_add(dev, opp->freq, opp->m_volt * 1000);
708 if (ret) {
709 dev_warn(dev, "failed to add opp %uHz %umV\n",
710 opp->freq, opp->m_volt);
711 while (idx-- > 0)
712 dev_pm_opp_remove(dev, (--opp)->freq);
713 return ret;
714 }
715 }
716 return 0;
717 }
718
scpi_sensor_get_capability(u16 * sensors)719 static int scpi_sensor_get_capability(u16 *sensors)
720 {
721 __le16 cap;
722 int ret;
723
724 ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap,
725 sizeof(cap));
726 if (!ret)
727 *sensors = le16_to_cpu(cap);
728
729 return ret;
730 }
731
scpi_sensor_get_info(u16 sensor_id,struct scpi_sensor_info * info)732 static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
733 {
734 __le16 id = cpu_to_le16(sensor_id);
735 struct _scpi_sensor_info _info;
736 int ret;
737
738 ret = scpi_send_message(CMD_SENSOR_INFO, &id, sizeof(id),
739 &_info, sizeof(_info));
740 if (!ret) {
741 memcpy(info, &_info, sizeof(*info));
742 info->sensor_id = le16_to_cpu(_info.sensor_id);
743 }
744
745 return ret;
746 }
747
scpi_sensor_get_value(u16 sensor,u64 * val)748 static int scpi_sensor_get_value(u16 sensor, u64 *val)
749 {
750 __le16 id = cpu_to_le16(sensor);
751 __le64 value;
752 int ret;
753
754 ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
755 &value, sizeof(value));
756 if (ret)
757 return ret;
758
759 if (scpi_info->is_legacy)
760 /* only 32-bits supported, upper 32 bits can be junk */
761 *val = le32_to_cpup((__le32 *)&value);
762 else
763 *val = le64_to_cpu(value);
764
765 return 0;
766 }
767
scpi_device_get_power_state(u16 dev_id)768 static int scpi_device_get_power_state(u16 dev_id)
769 {
770 int ret;
771 u8 pstate;
772 __le16 id = cpu_to_le16(dev_id);
773
774 ret = scpi_send_message(CMD_GET_DEVICE_PWR_STATE, &id,
775 sizeof(id), &pstate, sizeof(pstate));
776 return ret ? ret : pstate;
777 }
778
scpi_device_set_power_state(u16 dev_id,u8 pstate)779 static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
780 {
781 int stat;
782 struct dev_pstate_set dev_set = {
783 .dev_id = cpu_to_le16(dev_id),
784 .pstate = pstate,
785 };
786
787 return scpi_send_message(CMD_SET_DEVICE_PWR_STATE, &dev_set,
788 sizeof(dev_set), &stat, sizeof(stat));
789 }
790
791 static struct scpi_ops scpi_ops = {
792 .get_version = scpi_get_version,
793 .clk_get_range = scpi_clk_get_range,
794 .clk_get_val = scpi_clk_get_val,
795 .clk_set_val = scpi_clk_set_val,
796 .dvfs_get_idx = scpi_dvfs_get_idx,
797 .dvfs_set_idx = scpi_dvfs_set_idx,
798 .dvfs_get_info = scpi_dvfs_get_info,
799 .device_domain_id = scpi_dev_domain_id,
800 .get_transition_latency = scpi_dvfs_get_transition_latency,
801 .add_opps_to_device = scpi_dvfs_add_opps_to_device,
802 .sensor_get_capability = scpi_sensor_get_capability,
803 .sensor_get_info = scpi_sensor_get_info,
804 .sensor_get_value = scpi_sensor_get_value,
805 .device_get_power_state = scpi_device_get_power_state,
806 .device_set_power_state = scpi_device_set_power_state,
807 };
808
get_scpi_ops(void)809 struct scpi_ops *get_scpi_ops(void)
810 {
811 return scpi_info ? scpi_info->scpi_ops : NULL;
812 }
813 EXPORT_SYMBOL_GPL(get_scpi_ops);
814
scpi_init_versions(struct scpi_drvinfo * info)815 static int scpi_init_versions(struct scpi_drvinfo *info)
816 {
817 int ret;
818 struct scp_capabilities caps;
819
820 ret = scpi_send_message(CMD_SCPI_CAPABILITIES, NULL, 0,
821 &caps, sizeof(caps));
822 if (!ret) {
823 info->protocol_version = le32_to_cpu(caps.protocol_version);
824 info->firmware_version = le32_to_cpu(caps.platform_version);
825 }
826 /* Ignore error if not implemented */
827 if (scpi_info->is_legacy && ret == -EOPNOTSUPP)
828 return 0;
829
830 return ret;
831 }
832
protocol_version_show(struct device * dev,struct device_attribute * attr,char * buf)833 static ssize_t protocol_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\n",
839 FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
840 FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
841 }
842 static DEVICE_ATTR_RO(protocol_version);
843
firmware_version_show(struct device * dev,struct device_attribute * attr,char * buf)844 static ssize_t firmware_version_show(struct device *dev,
845 struct device_attribute *attr, char *buf)
846 {
847 struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
848
849 return sprintf(buf, "%lu.%lu.%lu\n",
850 FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
851 FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
852 FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
853 }
854 static DEVICE_ATTR_RO(firmware_version);
855
856 static struct attribute *versions_attrs[] = {
857 &dev_attr_firmware_version.attr,
858 &dev_attr_protocol_version.attr,
859 NULL,
860 };
861 ATTRIBUTE_GROUPS(versions);
862
scpi_free_channels(void * data)863 static void scpi_free_channels(void *data)
864 {
865 struct scpi_drvinfo *info = data;
866 int i;
867
868 for (i = 0; i < info->num_chans; i++)
869 mbox_free_channel(info->channels[i].chan);
870 }
871
scpi_remove(struct platform_device * pdev)872 static int scpi_remove(struct platform_device *pdev)
873 {
874 int i;
875 struct scpi_drvinfo *info = platform_get_drvdata(pdev);
876
877 scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
878
879 for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
880 kfree(info->dvfs[i]->opps);
881 kfree(info->dvfs[i]);
882 }
883
884 return 0;
885 }
886
887 #define MAX_SCPI_XFERS 10
scpi_alloc_xfer_list(struct device * dev,struct scpi_chan * ch)888 static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
889 {
890 int i;
891 struct scpi_xfer *xfers;
892
893 xfers = devm_kcalloc(dev, MAX_SCPI_XFERS, sizeof(*xfers), GFP_KERNEL);
894 if (!xfers)
895 return -ENOMEM;
896
897 ch->xfers = xfers;
898 for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++) {
899 init_completion(&xfers->done);
900 list_add_tail(&xfers->node, &ch->xfers_list);
901 }
902
903 return 0;
904 }
905
906 static const struct of_device_id legacy_scpi_of_match[] = {
907 {.compatible = "arm,scpi-pre-1.0"},
908 {},
909 };
910
scpi_probe(struct platform_device * pdev)911 static int scpi_probe(struct platform_device *pdev)
912 {
913 int count, idx, ret;
914 struct resource res;
915 struct device *dev = &pdev->dev;
916 struct device_node *np = dev->of_node;
917
918 scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
919 if (!scpi_info)
920 return -ENOMEM;
921
922 if (of_match_device(legacy_scpi_of_match, &pdev->dev))
923 scpi_info->is_legacy = true;
924
925 count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
926 if (count < 0) {
927 dev_err(dev, "no mboxes property in '%pOF'\n", np);
928 return -ENODEV;
929 }
930
931 scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
932 GFP_KERNEL);
933 if (!scpi_info->channels)
934 return -ENOMEM;
935
936 ret = devm_add_action(dev, scpi_free_channels, scpi_info);
937 if (ret)
938 return ret;
939
940 for (; scpi_info->num_chans < count; scpi_info->num_chans++) {
941 resource_size_t size;
942 int idx = scpi_info->num_chans;
943 struct scpi_chan *pchan = scpi_info->channels + idx;
944 struct mbox_client *cl = &pchan->cl;
945 struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
946
947 ret = of_address_to_resource(shmem, 0, &res);
948 of_node_put(shmem);
949 if (ret) {
950 dev_err(dev, "failed to get SCPI payload mem resource\n");
951 return ret;
952 }
953
954 size = resource_size(&res);
955 pchan->rx_payload = devm_ioremap(dev, res.start, size);
956 if (!pchan->rx_payload) {
957 dev_err(dev, "failed to ioremap SCPI payload\n");
958 return -EADDRNOTAVAIL;
959 }
960 pchan->tx_payload = pchan->rx_payload + (size >> 1);
961
962 cl->dev = dev;
963 cl->rx_callback = scpi_handle_remote_msg;
964 cl->tx_prepare = scpi_tx_prepare;
965 cl->tx_block = true;
966 cl->tx_tout = 20;
967 cl->knows_txdone = false; /* controller can't ack */
968
969 INIT_LIST_HEAD(&pchan->rx_pending);
970 INIT_LIST_HEAD(&pchan->xfers_list);
971 spin_lock_init(&pchan->rx_lock);
972 mutex_init(&pchan->xfers_lock);
973
974 ret = scpi_alloc_xfer_list(dev, pchan);
975 if (!ret) {
976 pchan->chan = mbox_request_channel(cl, idx);
977 if (!IS_ERR(pchan->chan))
978 continue;
979 ret = PTR_ERR(pchan->chan);
980 if (ret != -EPROBE_DEFER)
981 dev_err(dev, "failed to get channel%d err %d\n",
982 idx, ret);
983 }
984 return ret;
985 }
986
987 scpi_info->commands = scpi_std_commands;
988
989 platform_set_drvdata(pdev, scpi_info);
990
991 if (scpi_info->is_legacy) {
992 /* Replace with legacy variants */
993 scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
994 scpi_info->commands = scpi_legacy_commands;
995
996 /* Fill priority bitmap */
997 for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
998 set_bit(legacy_hpriority_cmds[idx],
999 scpi_info->cmd_priority);
1000 }
1001
1002 ret = scpi_init_versions(scpi_info);
1003 if (ret) {
1004 dev_err(dev, "incorrect or no SCP firmware found\n");
1005 return ret;
1006 }
1007
1008 if (scpi_info->is_legacy && !scpi_info->protocol_version &&
1009 !scpi_info->firmware_version)
1010 dev_info(dev, "SCP Protocol legacy pre-1.0 firmware\n");
1011 else
1012 dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
1013 FIELD_GET(PROTO_REV_MAJOR_MASK,
1014 scpi_info->protocol_version),
1015 FIELD_GET(PROTO_REV_MINOR_MASK,
1016 scpi_info->protocol_version),
1017 FIELD_GET(FW_REV_MAJOR_MASK,
1018 scpi_info->firmware_version),
1019 FIELD_GET(FW_REV_MINOR_MASK,
1020 scpi_info->firmware_version),
1021 FIELD_GET(FW_REV_PATCH_MASK,
1022 scpi_info->firmware_version));
1023 scpi_info->scpi_ops = &scpi_ops;
1024
1025 ret = devm_device_add_groups(dev, versions_groups);
1026 if (ret)
1027 dev_err(dev, "unable to create sysfs version group\n");
1028
1029 return devm_of_platform_populate(dev);
1030 }
1031
1032 static const struct of_device_id scpi_of_match[] = {
1033 {.compatible = "arm,scpi"},
1034 {.compatible = "arm,scpi-pre-1.0"},
1035 {},
1036 };
1037
1038 MODULE_DEVICE_TABLE(of, scpi_of_match);
1039
1040 static struct platform_driver scpi_driver = {
1041 .driver = {
1042 .name = "scpi_protocol",
1043 .of_match_table = scpi_of_match,
1044 },
1045 .probe = scpi_probe,
1046 .remove = scpi_remove,
1047 };
1048 module_platform_driver(scpi_driver);
1049
1050 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1051 MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1052 MODULE_LICENSE("GPL v2");
1053
