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of: MSI: Simplify irqdomain lookup
[linux/fpc-iii.git] / drivers / firmware / arm_scpi.c
blob6174db80c66361d2046a3548c6f5b14d36f8c999
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/device.h>
32 #include <linux/err.h>
33 #include <linux/export.h>
34 #include <linux/io.h>
35 #include <linux/kernel.h>
36 #include <linux/list.h>
37 #include <linux/mailbox_client.h>
38 #include <linux/module.h>
39 #include <linux/of_address.h>
40 #include <linux/of_platform.h>
41 #include <linux/printk.h>
42 #include <linux/scpi_protocol.h>
43 #include <linux/slab.h>
44 #include <linux/sort.h>
45 #include <linux/spinlock.h>
46
47 #define CMD_ID_SHIFT 0
48 #define CMD_ID_MASK 0x7f
49 #define CMD_TOKEN_ID_SHIFT 8
50 #define CMD_TOKEN_ID_MASK 0xff
51 #define CMD_DATA_SIZE_SHIFT 16
52 #define CMD_DATA_SIZE_MASK 0x1ff
53 #define PACK_SCPI_CMD(cmd_id, tx_sz) \
54 ((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) | \
55 (((tx_sz) & CMD_DATA_SIZE_MASK) << CMD_DATA_SIZE_SHIFT))
56 #define ADD_SCPI_TOKEN(cmd, token) \
57 ((cmd) |= (((token) & CMD_TOKEN_ID_MASK) << CMD_TOKEN_ID_SHIFT))
58
59 #define CMD_SIZE(cmd) (((cmd) >> CMD_DATA_SIZE_SHIFT) & CMD_DATA_SIZE_MASK)
60 #define CMD_UNIQ_MASK (CMD_TOKEN_ID_MASK << CMD_TOKEN_ID_SHIFT | CMD_ID_MASK)
61 #define CMD_XTRACT_UNIQ(cmd) ((cmd) & CMD_UNIQ_MASK)
62
63 #define SCPI_SLOT 0
64
65 #define MAX_DVFS_DOMAINS 8
66 #define MAX_DVFS_OPPS 8
67 #define DVFS_LATENCY(hdr) (le32_to_cpu(hdr) >> 16)
68 #define DVFS_OPP_COUNT(hdr) ((le32_to_cpu(hdr) >> 8) & 0xff)
69
70 #define PROTOCOL_REV_MINOR_BITS 16
71 #define PROTOCOL_REV_MINOR_MASK ((1U << PROTOCOL_REV_MINOR_BITS) - 1)
72 #define PROTOCOL_REV_MAJOR(x) ((x) >> PROTOCOL_REV_MINOR_BITS)
73 #define PROTOCOL_REV_MINOR(x) ((x) & PROTOCOL_REV_MINOR_MASK)
74
75 #define FW_REV_MAJOR_BITS 24
76 #define FW_REV_MINOR_BITS 16
77 #define FW_REV_PATCH_MASK ((1U << FW_REV_MINOR_BITS) - 1)
78 #define FW_REV_MINOR_MASK ((1U << FW_REV_MAJOR_BITS) - 1)
79 #define FW_REV_MAJOR(x) ((x) >> FW_REV_MAJOR_BITS)
80 #define FW_REV_MINOR(x) (((x) & FW_REV_MINOR_MASK) >> FW_REV_MINOR_BITS)
81 #define FW_REV_PATCH(x) ((x) & FW_REV_PATCH_MASK)
82
83 #define MAX_RX_TIMEOUT (msecs_to_jiffies(20))
84
85 enum scpi_error_codes {
86 SCPI_SUCCESS = 0, /* Success */
87 SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
88 SCPI_ERR_ALIGN = 2, /* Invalid alignment */
89 SCPI_ERR_SIZE = 3, /* Invalid size */
90 SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
91 SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
92 SCPI_ERR_RANGE = 6, /* Value out of range */
93 SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
94 SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
95 SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
96 SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
97 SCPI_ERR_DEVICE = 11, /* Device error */
98 SCPI_ERR_BUSY = 12, /* Device busy */
99 SCPI_ERR_MAX
100 };
101
102 enum scpi_std_cmd {
103 SCPI_CMD_INVALID = 0x00,
104 SCPI_CMD_SCPI_READY = 0x01,
105 SCPI_CMD_SCPI_CAPABILITIES = 0x02,
106 SCPI_CMD_SET_CSS_PWR_STATE = 0x03,
107 SCPI_CMD_GET_CSS_PWR_STATE = 0x04,
108 SCPI_CMD_SET_SYS_PWR_STATE = 0x05,
109 SCPI_CMD_SET_CPU_TIMER = 0x06,
110 SCPI_CMD_CANCEL_CPU_TIMER = 0x07,
111 SCPI_CMD_DVFS_CAPABILITIES = 0x08,
112 SCPI_CMD_GET_DVFS_INFO = 0x09,
113 SCPI_CMD_SET_DVFS = 0x0a,
114 SCPI_CMD_GET_DVFS = 0x0b,
115 SCPI_CMD_GET_DVFS_STAT = 0x0c,
116 SCPI_CMD_CLOCK_CAPABILITIES = 0x0d,
117 SCPI_CMD_GET_CLOCK_INFO = 0x0e,
118 SCPI_CMD_SET_CLOCK_VALUE = 0x0f,
119 SCPI_CMD_GET_CLOCK_VALUE = 0x10,
120 SCPI_CMD_PSU_CAPABILITIES = 0x11,
121 SCPI_CMD_GET_PSU_INFO = 0x12,
122 SCPI_CMD_SET_PSU = 0x13,
123 SCPI_CMD_GET_PSU = 0x14,
124 SCPI_CMD_SENSOR_CAPABILITIES = 0x15,
125 SCPI_CMD_SENSOR_INFO = 0x16,
126 SCPI_CMD_SENSOR_VALUE = 0x17,
127 SCPI_CMD_SENSOR_CFG_PERIODIC = 0x18,
128 SCPI_CMD_SENSOR_CFG_BOUNDS = 0x19,
129 SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1a,
130 SCPI_CMD_SET_DEVICE_PWR_STATE = 0x1b,
131 SCPI_CMD_GET_DEVICE_PWR_STATE = 0x1c,
132 SCPI_CMD_COUNT
133 };
134
135 struct scpi_xfer {
136 u32 slot; /* has to be first element */
137 u32 cmd;
138 u32 status;
139 const void *tx_buf;
140 void *rx_buf;
141 unsigned int tx_len;
142 unsigned int rx_len;
143 struct list_head node;
144 struct completion done;
145 };
146
147 struct scpi_chan {
148 struct mbox_client cl;
149 struct mbox_chan *chan;
150 void __iomem *tx_payload;
151 void __iomem *rx_payload;
152 struct list_head rx_pending;
153 struct list_head xfers_list;
154 struct scpi_xfer *xfers;
155 spinlock_t rx_lock; /* locking for the rx pending list */
156 struct mutex xfers_lock;
157 u8 token;
158 };
159
160 struct scpi_drvinfo {
161 u32 protocol_version;
162 u32 firmware_version;
163 int num_chans;
164 atomic_t next_chan;
165 struct scpi_ops *scpi_ops;
166 struct scpi_chan *channels;
167 struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
168 };
169
170 /*
171 * The SCP firmware only executes in little-endian mode, so any buffers
172 * shared through SCPI should have their contents converted to little-endian
173 */
174 struct scpi_shared_mem {
175 __le32 command;
176 __le32 status;
177 u8 payload[0];
178 } __packed;
179
180 struct scp_capabilities {
181 __le32 protocol_version;
182 __le32 event_version;
183 __le32 platform_version;
184 __le32 commands[4];
185 } __packed;
186
187 struct clk_get_info {
188 __le16 id;
189 __le16 flags;
190 __le32 min_rate;
191 __le32 max_rate;
192 u8 name[20];
193 } __packed;
194
195 struct clk_get_value {
196 __le32 rate;
197 } __packed;
198
199 struct clk_set_value {
200 __le16 id;
201 __le16 reserved;
202 __le32 rate;
203 } __packed;
204
205 struct dvfs_info {
206 __le32 header;
207 struct {
208 __le32 freq;
209 __le32 m_volt;
210 } opps[MAX_DVFS_OPPS];
211 } __packed;
212
213 struct dvfs_get {
214 u8 index;
215 } __packed;
216
217 struct dvfs_set {
218 u8 domain;
219 u8 index;
220 } __packed;
221
222 struct sensor_capabilities {
223 __le16 sensors;
224 } __packed;
225
226 struct _scpi_sensor_info {
227 __le16 sensor_id;
228 u8 class;
229 u8 trigger_type;
230 char name[20];
231 };
232
233 struct sensor_value {
234 __le32 val;
235 } __packed;
236
237 static struct scpi_drvinfo *scpi_info;
238
239 static int scpi_linux_errmap[SCPI_ERR_MAX] = {
240 /* better than switch case as long as return value is continuous */
241 0, /* SCPI_SUCCESS */
242 -EINVAL, /* SCPI_ERR_PARAM */
243 -ENOEXEC, /* SCPI_ERR_ALIGN */
244 -EMSGSIZE, /* SCPI_ERR_SIZE */
245 -EINVAL, /* SCPI_ERR_HANDLER */
246 -EACCES, /* SCPI_ERR_ACCESS */
247 -ERANGE, /* SCPI_ERR_RANGE */
248 -ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
249 -ENOMEM, /* SCPI_ERR_NOMEM */
250 -EINVAL, /* SCPI_ERR_PWRSTATE */
251 -EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
252 -EIO, /* SCPI_ERR_DEVICE */
253 -EBUSY, /* SCPI_ERR_BUSY */
254 };
255
256 static inline int scpi_to_linux_errno(int errno)
257 {
258 if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
259 return scpi_linux_errmap[errno];
260 return -EIO;
261 }
262
263 static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
264 {
265 unsigned long flags;
266 struct scpi_xfer *t, *match = NULL;
267
268 spin_lock_irqsave(&ch->rx_lock, flags);
269 if (list_empty(&ch->rx_pending)) {
270 spin_unlock_irqrestore(&ch->rx_lock, flags);
271 return;
272 }
273
274 list_for_each_entry(t, &ch->rx_pending, node)
275 if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
276 list_del(&t->node);
277 match = t;
278 break;
279 }
280 /* check if wait_for_completion is in progress or timed-out */
281 if (match && !completion_done(&match->done)) {
282 struct scpi_shared_mem *mem = ch->rx_payload;
283 unsigned int len = min(match->rx_len, CMD_SIZE(cmd));
284
285 match->status = le32_to_cpu(mem->status);
286 memcpy_fromio(match->rx_buf, mem->payload, len);
287 if (match->rx_len > len)
288 memset(match->rx_buf + len, 0, match->rx_len - len);
289 complete(&match->done);
290 }
291 spin_unlock_irqrestore(&ch->rx_lock, flags);
292 }
293
294 static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
295 {
296 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
297 struct scpi_shared_mem *mem = ch->rx_payload;
298 u32 cmd = le32_to_cpu(mem->command);
299
300 scpi_process_cmd(ch, cmd);
301 }
302
303 static void scpi_tx_prepare(struct mbox_client *c, void *msg)
304 {
305 unsigned long flags;
306 struct scpi_xfer *t = msg;
307 struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
308 struct scpi_shared_mem *mem = (struct scpi_shared_mem *)ch->tx_payload;
309
310 if (t->tx_buf)
311 memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
312 if (t->rx_buf) {
313 if (!(++ch->token))
314 ++ch->token;
315 ADD_SCPI_TOKEN(t->cmd, ch->token);
316 spin_lock_irqsave(&ch->rx_lock, flags);
317 list_add_tail(&t->node, &ch->rx_pending);
318 spin_unlock_irqrestore(&ch->rx_lock, flags);
319 }
320 mem->command = cpu_to_le32(t->cmd);
321 }
322
323 static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
324 {
325 struct scpi_xfer *t;
326
327 mutex_lock(&ch->xfers_lock);
328 if (list_empty(&ch->xfers_list)) {
329 mutex_unlock(&ch->xfers_lock);
330 return NULL;
331 }
332 t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
333 list_del(&t->node);
334 mutex_unlock(&ch->xfers_lock);
335 return t;
336 }
337
338 static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
339 {
340 mutex_lock(&ch->xfers_lock);
341 list_add_tail(&t->node, &ch->xfers_list);
342 mutex_unlock(&ch->xfers_lock);
343 }
344
345 static int scpi_send_message(u8 cmd, void *tx_buf, unsigned int tx_len,
346 void *rx_buf, unsigned int rx_len)
347 {
348 int ret;
349 u8 chan;
350 struct scpi_xfer *msg;
351 struct scpi_chan *scpi_chan;
352
353 chan = atomic_inc_return(&scpi_info->next_chan) % scpi_info->num_chans;
354 scpi_chan = scpi_info->channels + chan;
355
356 msg = get_scpi_xfer(scpi_chan);
357 if (!msg)
358 return -ENOMEM;
359
360 msg->slot = BIT(SCPI_SLOT);
361 msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
362 msg->tx_buf = tx_buf;
363 msg->tx_len = tx_len;
364 msg->rx_buf = rx_buf;
365 msg->rx_len = rx_len;
366 init_completion(&msg->done);
367
368 ret = mbox_send_message(scpi_chan->chan, msg);
369 if (ret < 0 || !rx_buf)
370 goto out;
371
372 if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
373 ret = -ETIMEDOUT;
374 else
375 /* first status word */
376 ret = le32_to_cpu(msg->status);
377 out:
378 if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
379 scpi_process_cmd(scpi_chan, msg->cmd);
380
381 put_scpi_xfer(msg, scpi_chan);
382 /* SCPI error codes > 0, translate them to Linux scale*/
383 return ret > 0 ? scpi_to_linux_errno(ret) : ret;
384 }
385
386 static u32 scpi_get_version(void)
387 {
388 return scpi_info->protocol_version;
389 }
390
391 static int
392 scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
393 {
394 int ret;
395 struct clk_get_info clk;
396 __le16 le_clk_id = cpu_to_le16(clk_id);
397
398 ret = scpi_send_message(SCPI_CMD_GET_CLOCK_INFO, &le_clk_id,
399 sizeof(le_clk_id), &clk, sizeof(clk));
400 if (!ret) {
401 *min = le32_to_cpu(clk.min_rate);
402 *max = le32_to_cpu(clk.max_rate);
403 }
404 return ret;
405 }
406
407 static unsigned long scpi_clk_get_val(u16 clk_id)
408 {
409 int ret;
410 struct clk_get_value clk;
411 __le16 le_clk_id = cpu_to_le16(clk_id);
412
413 ret = scpi_send_message(SCPI_CMD_GET_CLOCK_VALUE, &le_clk_id,
414 sizeof(le_clk_id), &clk, sizeof(clk));
415 return ret ? ret : le32_to_cpu(clk.rate);
416 }
417
418 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
419 {
420 int stat;
421 struct clk_set_value clk = {
422 .id = cpu_to_le16(clk_id),
423 .rate = cpu_to_le32(rate)
424 };
425
426 return scpi_send_message(SCPI_CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
427 &stat, sizeof(stat));
428 }
429
430 static int scpi_dvfs_get_idx(u8 domain)
431 {
432 int ret;
433 struct dvfs_get dvfs;
434
435 ret = scpi_send_message(SCPI_CMD_GET_DVFS, &domain, sizeof(domain),
436 &dvfs, sizeof(dvfs));
437 return ret ? ret : dvfs.index;
438 }
439
440 static int scpi_dvfs_set_idx(u8 domain, u8 index)
441 {
442 int stat;
443 struct dvfs_set dvfs = {domain, index};
444
445 return scpi_send_message(SCPI_CMD_SET_DVFS, &dvfs, sizeof(dvfs),
446 &stat, sizeof(stat));
447 }
448
449 static int opp_cmp_func(const void *opp1, const void *opp2)
450 {
451 const struct scpi_opp *t1 = opp1, *t2 = opp2;
452
453 return t1->freq - t2->freq;
454 }
455
456 static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
457 {
458 struct scpi_dvfs_info *info;
459 struct scpi_opp *opp;
460 struct dvfs_info buf;
461 int ret, i;
462
463 if (domain >= MAX_DVFS_DOMAINS)
464 return ERR_PTR(-EINVAL);
465
466 if (scpi_info->dvfs[domain]) /* data already populated */
467 return scpi_info->dvfs[domain];
468
469 ret = scpi_send_message(SCPI_CMD_GET_DVFS_INFO, &domain, sizeof(domain),
470 &buf, sizeof(buf));
471
472 if (ret)
473 return ERR_PTR(ret);
474
475 info = kmalloc(sizeof(*info), GFP_KERNEL);
476 if (!info)
477 return ERR_PTR(-ENOMEM);
478
479 info->count = DVFS_OPP_COUNT(buf.header);
480 info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */
481
482 info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
483 if (!info->opps) {
484 kfree(info);
485 return ERR_PTR(-ENOMEM);
486 }
487
488 for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
489 opp->freq = le32_to_cpu(buf.opps[i].freq);
490 opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
491 }
492
493 sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
494
495 scpi_info->dvfs[domain] = info;
496 return info;
497 }
498
499 static int scpi_sensor_get_capability(u16 *sensors)
500 {
501 struct sensor_capabilities cap_buf;
502 int ret;
503
504 ret = scpi_send_message(SCPI_CMD_SENSOR_CAPABILITIES, NULL, 0, &cap_buf,
505 sizeof(cap_buf));
506 if (!ret)
507 *sensors = le16_to_cpu(cap_buf.sensors);
508
509 return ret;
510 }
511
512 static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
513 {
514 __le16 id = cpu_to_le16(sensor_id);
515 struct _scpi_sensor_info _info;
516 int ret;
517
518 ret = scpi_send_message(SCPI_CMD_SENSOR_INFO, &id, sizeof(id),
519 &_info, sizeof(_info));
520 if (!ret) {
521 memcpy(info, &_info, sizeof(*info));
522 info->sensor_id = le16_to_cpu(_info.sensor_id);
523 }
524
525 return ret;
526 }
527
528 int scpi_sensor_get_value(u16 sensor, u32 *val)
529 {
530 struct sensor_value buf;
531 int ret;
532
533 ret = scpi_send_message(SCPI_CMD_SENSOR_VALUE, &sensor, sizeof(sensor),
534 &buf, sizeof(buf));
535 if (!ret)
536 *val = le32_to_cpu(buf.val);
537
538 return ret;
539 }
540
541 static struct scpi_ops scpi_ops = {
542 .get_version = scpi_get_version,
543 .clk_get_range = scpi_clk_get_range,
544 .clk_get_val = scpi_clk_get_val,
545 .clk_set_val = scpi_clk_set_val,
546 .dvfs_get_idx = scpi_dvfs_get_idx,
547 .dvfs_set_idx = scpi_dvfs_set_idx,
548 .dvfs_get_info = scpi_dvfs_get_info,
549 .sensor_get_capability = scpi_sensor_get_capability,
550 .sensor_get_info = scpi_sensor_get_info,
551 .sensor_get_value = scpi_sensor_get_value,
552 };
553
554 struct scpi_ops *get_scpi_ops(void)
555 {
556 return scpi_info ? scpi_info->scpi_ops : NULL;
557 }
558 EXPORT_SYMBOL_GPL(get_scpi_ops);
559
560 static int scpi_init_versions(struct scpi_drvinfo *info)
561 {
562 int ret;
563 struct scp_capabilities caps;
564
565 ret = scpi_send_message(SCPI_CMD_SCPI_CAPABILITIES, NULL, 0,
566 &caps, sizeof(caps));
567 if (!ret) {
568 info->protocol_version = le32_to_cpu(caps.protocol_version);
569 info->firmware_version = le32_to_cpu(caps.platform_version);
570 }
571 return ret;
572 }
573
574 static ssize_t protocol_version_show(struct device *dev,
575 struct device_attribute *attr, char *buf)
576 {
577 struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
578
579 return sprintf(buf, "%d.%d\n",
580 PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
581 PROTOCOL_REV_MINOR(scpi_info->protocol_version));
582 }
583 static DEVICE_ATTR_RO(protocol_version);
584
585 static ssize_t firmware_version_show(struct device *dev,
586 struct device_attribute *attr, char *buf)
587 {
588 struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
589
590 return sprintf(buf, "%d.%d.%d\n",
591 FW_REV_MAJOR(scpi_info->firmware_version),
592 FW_REV_MINOR(scpi_info->firmware_version),
593 FW_REV_PATCH(scpi_info->firmware_version));
594 }
595 static DEVICE_ATTR_RO(firmware_version);
596
597 static struct attribute *versions_attrs[] = {
598 &dev_attr_firmware_version.attr,
599 &dev_attr_protocol_version.attr,
600 NULL,
601 };
602 ATTRIBUTE_GROUPS(versions);
603
604 static void
605 scpi_free_channels(struct device *dev, struct scpi_chan *pchan, int count)
606 {
607 int i;
608
609 for (i = 0; i < count && pchan->chan; i++, pchan++) {
610 mbox_free_channel(pchan->chan);
611 devm_kfree(dev, pchan->xfers);
612 devm_iounmap(dev, pchan->rx_payload);
613 }
614 }
615
616 static int scpi_remove(struct platform_device *pdev)
617 {
618 int i;
619 struct device *dev = &pdev->dev;
620 struct scpi_drvinfo *info = platform_get_drvdata(pdev);
621
622 scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
623
624 of_platform_depopulate(dev);
625 sysfs_remove_groups(&dev->kobj, versions_groups);
626 scpi_free_channels(dev, info->channels, info->num_chans);
627 platform_set_drvdata(pdev, NULL);
628
629 for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
630 kfree(info->dvfs[i]->opps);
631 kfree(info->dvfs[i]);
632 }
633 devm_kfree(dev, info->channels);
634 devm_kfree(dev, info);
635
636 return 0;
637 }
638
639 #define MAX_SCPI_XFERS 10
640 static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
641 {
642 int i;
643 struct scpi_xfer *xfers;
644
645 xfers = devm_kzalloc(dev, MAX_SCPI_XFERS * sizeof(*xfers), GFP_KERNEL);
646 if (!xfers)
647 return -ENOMEM;
648
649 ch->xfers = xfers;
650 for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++)
651 list_add_tail(&xfers->node, &ch->xfers_list);
652 return 0;
653 }
654
655 static int scpi_probe(struct platform_device *pdev)
656 {
657 int count, idx, ret;
658 struct resource res;
659 struct scpi_chan *scpi_chan;
660 struct device *dev = &pdev->dev;
661 struct device_node *np = dev->of_node;
662
663 scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
664 if (!scpi_info)
665 return -ENOMEM;
666
667 count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
668 if (count < 0) {
669 dev_err(dev, "no mboxes property in '%s'\n", np->full_name);
670 return -ENODEV;
671 }
672
673 scpi_chan = devm_kcalloc(dev, count, sizeof(*scpi_chan), GFP_KERNEL);
674 if (!scpi_chan)
675 return -ENOMEM;
676
677 for (idx = 0; idx < count; idx++) {
678 resource_size_t size;
679 struct scpi_chan *pchan = scpi_chan + idx;
680 struct mbox_client *cl = &pchan->cl;
681 struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
682
683 if (of_address_to_resource(shmem, 0, &res)) {
684 dev_err(dev, "failed to get SCPI payload mem resource\n");
685 ret = -EINVAL;
686 goto err;
687 }
688
689 size = resource_size(&res);
690 pchan->rx_payload = devm_ioremap(dev, res.start, size);
691 if (!pchan->rx_payload) {
692 dev_err(dev, "failed to ioremap SCPI payload\n");
693 ret = -EADDRNOTAVAIL;
694 goto err;
695 }
696 pchan->tx_payload = pchan->rx_payload + (size >> 1);
697
698 cl->dev = dev;
699 cl->rx_callback = scpi_handle_remote_msg;
700 cl->tx_prepare = scpi_tx_prepare;
701 cl->tx_block = true;
702 cl->tx_tout = 50;
703 cl->knows_txdone = false; /* controller can't ack */
704
705 INIT_LIST_HEAD(&pchan->rx_pending);
706 INIT_LIST_HEAD(&pchan->xfers_list);
707 spin_lock_init(&pchan->rx_lock);
708 mutex_init(&pchan->xfers_lock);
709
710 ret = scpi_alloc_xfer_list(dev, pchan);
711 if (!ret) {
712 pchan->chan = mbox_request_channel(cl, idx);
713 if (!IS_ERR(pchan->chan))
714 continue;
715 ret = PTR_ERR(pchan->chan);
716 if (ret != -EPROBE_DEFER)
717 dev_err(dev, "failed to get channel%d err %d\n",
718 idx, ret);
719 }
720 err:
721 scpi_free_channels(dev, scpi_chan, idx);
722 scpi_info = NULL;
723 return ret;
724 }
725
726 scpi_info->channels = scpi_chan;
727 scpi_info->num_chans = count;
728 platform_set_drvdata(pdev, scpi_info);
729
730 ret = scpi_init_versions(scpi_info);
731 if (ret) {
732 dev_err(dev, "incorrect or no SCP firmware found\n");
733 scpi_remove(pdev);
734 return ret;
735 }
736
737 _dev_info(dev, "SCP Protocol %d.%d Firmware %d.%d.%d version\n",
738 PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
739 PROTOCOL_REV_MINOR(scpi_info->protocol_version),
740 FW_REV_MAJOR(scpi_info->firmware_version),
741 FW_REV_MINOR(scpi_info->firmware_version),
742 FW_REV_PATCH(scpi_info->firmware_version));
743 scpi_info->scpi_ops = &scpi_ops;
744
745 ret = sysfs_create_groups(&dev->kobj, versions_groups);
746 if (ret)
747 dev_err(dev, "unable to create sysfs version group\n");
748
749 return of_platform_populate(dev->of_node, NULL, NULL, dev);
750 }
751
752 static const struct of_device_id scpi_of_match[] = {
753 {.compatible = "arm,scpi"},
754 {},
755 };
756
757 MODULE_DEVICE_TABLE(of, scpi_of_match);
758
759 static struct platform_driver scpi_driver = {
760 .driver = {
761 .name = "scpi_protocol",
762 .of_match_table = scpi_of_match,
763 },
764 .probe = scpi_probe,
765 .remove = scpi_remove,
766 };
767 module_platform_driver(scpi_driver);
768
769 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
770 MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
771 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support