GNU Linux-libre 5.19-rc6-gnu
[releases.git] / drivers / firmware / arm_scpi.c
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
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
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
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
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
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
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
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
526 static u32 scpi_get_version(void)
527 {
528         return scpi_info->protocol_version;
529 }
530
531 static int
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
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         if (ret)
556                 return 0;
557
558         return le32_to_cpu(rate);
559 }
560
561 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
562 {
563         int stat;
564         struct clk_set_value clk = {
565                 .id = cpu_to_le16(clk_id),
566                 .rate = cpu_to_le32(rate)
567         };
568
569         return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
570                                  &stat, sizeof(stat));
571 }
572
573 static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
574 {
575         int stat;
576         struct legacy_clk_set_value clk = {
577                 .id = cpu_to_le16(clk_id),
578                 .rate = cpu_to_le32(rate)
579         };
580
581         return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
582                                  &stat, sizeof(stat));
583 }
584
585 static int scpi_dvfs_get_idx(u8 domain)
586 {
587         int ret;
588         u8 dvfs_idx;
589
590         ret = scpi_send_message(CMD_GET_DVFS, &domain, sizeof(domain),
591                                 &dvfs_idx, sizeof(dvfs_idx));
592
593         return ret ? ret : dvfs_idx;
594 }
595
596 static int scpi_dvfs_set_idx(u8 domain, u8 index)
597 {
598         int stat;
599         struct dvfs_set dvfs = {domain, index};
600
601         return scpi_send_message(CMD_SET_DVFS, &dvfs, sizeof(dvfs),
602                                  &stat, sizeof(stat));
603 }
604
605 static int opp_cmp_func(const void *opp1, const void *opp2)
606 {
607         const struct scpi_opp *t1 = opp1, *t2 = opp2;
608
609         return t1->freq - t2->freq;
610 }
611
612 static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
613 {
614         struct scpi_dvfs_info *info;
615         struct scpi_opp *opp;
616         struct dvfs_info buf;
617         int ret, i;
618
619         if (domain >= MAX_DVFS_DOMAINS)
620                 return ERR_PTR(-EINVAL);
621
622         if (scpi_info->dvfs[domain])    /* data already populated */
623                 return scpi_info->dvfs[domain];
624
625         ret = scpi_send_message(CMD_GET_DVFS_INFO, &domain, sizeof(domain),
626                                 &buf, sizeof(buf));
627         if (ret)
628                 return ERR_PTR(ret);
629
630         info = kmalloc(sizeof(*info), GFP_KERNEL);
631         if (!info)
632                 return ERR_PTR(-ENOMEM);
633
634         info->count = buf.opp_count;
635         info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
636
637         info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
638         if (!info->opps) {
639                 kfree(info);
640                 return ERR_PTR(-ENOMEM);
641         }
642
643         for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
644                 opp->freq = le32_to_cpu(buf.opps[i].freq);
645                 opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
646         }
647
648         sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
649
650         scpi_info->dvfs[domain] = info;
651         return info;
652 }
653
654 static int scpi_dev_domain_id(struct device *dev)
655 {
656         struct of_phandle_args clkspec;
657
658         if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
659                                        0, &clkspec))
660                 return -EINVAL;
661
662         return clkspec.args[0];
663 }
664
665 static struct scpi_dvfs_info *scpi_dvfs_info(struct device *dev)
666 {
667         int domain = scpi_dev_domain_id(dev);
668
669         if (domain < 0)
670                 return ERR_PTR(domain);
671
672         return scpi_dvfs_get_info(domain);
673 }
674
675 static int scpi_dvfs_get_transition_latency(struct device *dev)
676 {
677         struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
678
679         if (IS_ERR(info))
680                 return PTR_ERR(info);
681
682         return info->latency;
683 }
684
685 static int scpi_dvfs_add_opps_to_device(struct device *dev)
686 {
687         int idx, ret;
688         struct scpi_opp *opp;
689         struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
690
691         if (IS_ERR(info))
692                 return PTR_ERR(info);
693
694         if (!info->opps)
695                 return -EIO;
696
697         for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
698                 ret = dev_pm_opp_add(dev, opp->freq, opp->m_volt * 1000);
699                 if (ret) {
700                         dev_warn(dev, "failed to add opp %uHz %umV\n",
701                                  opp->freq, opp->m_volt);
702                         while (idx-- > 0)
703                                 dev_pm_opp_remove(dev, (--opp)->freq);
704                         return ret;
705                 }
706         }
707         return 0;
708 }
709
710 static int scpi_sensor_get_capability(u16 *sensors)
711 {
712         __le16 cap;
713         int ret;
714
715         ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap,
716                                 sizeof(cap));
717         if (!ret)
718                 *sensors = le16_to_cpu(cap);
719
720         return ret;
721 }
722
723 static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
724 {
725         __le16 id = cpu_to_le16(sensor_id);
726         struct _scpi_sensor_info _info;
727         int ret;
728
729         ret = scpi_send_message(CMD_SENSOR_INFO, &id, sizeof(id),
730                                 &_info, sizeof(_info));
731         if (!ret) {
732                 memcpy(info, &_info, sizeof(*info));
733                 info->sensor_id = le16_to_cpu(_info.sensor_id);
734         }
735
736         return ret;
737 }
738
739 static int scpi_sensor_get_value(u16 sensor, u64 *val)
740 {
741         __le16 id = cpu_to_le16(sensor);
742         __le64 value;
743         int ret;
744
745         ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
746                                 &value, sizeof(value));
747         if (ret)
748                 return ret;
749
750         if (scpi_info->is_legacy)
751                 /* only 32-bits supported, upper 32 bits can be junk */
752                 *val = le32_to_cpup((__le32 *)&value);
753         else
754                 *val = le64_to_cpu(value);
755
756         return 0;
757 }
758
759 static int scpi_device_get_power_state(u16 dev_id)
760 {
761         int ret;
762         u8 pstate;
763         __le16 id = cpu_to_le16(dev_id);
764
765         ret = scpi_send_message(CMD_GET_DEVICE_PWR_STATE, &id,
766                                 sizeof(id), &pstate, sizeof(pstate));
767         return ret ? ret : pstate;
768 }
769
770 static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
771 {
772         int stat;
773         struct dev_pstate_set dev_set = {
774                 .dev_id = cpu_to_le16(dev_id),
775                 .pstate = pstate,
776         };
777
778         return scpi_send_message(CMD_SET_DEVICE_PWR_STATE, &dev_set,
779                                  sizeof(dev_set), &stat, sizeof(stat));
780 }
781
782 static struct scpi_ops scpi_ops = {
783         .get_version = scpi_get_version,
784         .clk_get_range = scpi_clk_get_range,
785         .clk_get_val = scpi_clk_get_val,
786         .clk_set_val = scpi_clk_set_val,
787         .dvfs_get_idx = scpi_dvfs_get_idx,
788         .dvfs_set_idx = scpi_dvfs_set_idx,
789         .dvfs_get_info = scpi_dvfs_get_info,
790         .device_domain_id = scpi_dev_domain_id,
791         .get_transition_latency = scpi_dvfs_get_transition_latency,
792         .add_opps_to_device = scpi_dvfs_add_opps_to_device,
793         .sensor_get_capability = scpi_sensor_get_capability,
794         .sensor_get_info = scpi_sensor_get_info,
795         .sensor_get_value = scpi_sensor_get_value,
796         .device_get_power_state = scpi_device_get_power_state,
797         .device_set_power_state = scpi_device_set_power_state,
798 };
799
800 struct scpi_ops *get_scpi_ops(void)
801 {
802         return scpi_info ? scpi_info->scpi_ops : NULL;
803 }
804 EXPORT_SYMBOL_GPL(get_scpi_ops);
805
806 static int scpi_init_versions(struct scpi_drvinfo *info)
807 {
808         int ret;
809         struct scp_capabilities caps;
810
811         ret = scpi_send_message(CMD_SCPI_CAPABILITIES, NULL, 0,
812                                 &caps, sizeof(caps));
813         if (!ret) {
814                 info->protocol_version = le32_to_cpu(caps.protocol_version);
815                 info->firmware_version = le32_to_cpu(caps.platform_version);
816         }
817         /* Ignore error if not implemented */
818         if (scpi_info->is_legacy && ret == -EOPNOTSUPP)
819                 return 0;
820
821         return ret;
822 }
823
824 static ssize_t protocol_version_show(struct device *dev,
825                                      struct device_attribute *attr, char *buf)
826 {
827         struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
828
829         return sprintf(buf, "%lu.%lu\n",
830                 FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
831                 FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
832 }
833 static DEVICE_ATTR_RO(protocol_version);
834
835 static ssize_t firmware_version_show(struct device *dev,
836                                      struct device_attribute *attr, char *buf)
837 {
838         struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
839
840         return sprintf(buf, "%lu.%lu.%lu\n",
841                 FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
842                 FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
843                 FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
844 }
845 static DEVICE_ATTR_RO(firmware_version);
846
847 static struct attribute *versions_attrs[] = {
848         &dev_attr_firmware_version.attr,
849         &dev_attr_protocol_version.attr,
850         NULL,
851 };
852 ATTRIBUTE_GROUPS(versions);
853
854 static void scpi_free_channels(void *data)
855 {
856         struct scpi_drvinfo *info = data;
857         int i;
858
859         for (i = 0; i < info->num_chans; i++)
860                 mbox_free_channel(info->channels[i].chan);
861 }
862
863 static int scpi_remove(struct platform_device *pdev)
864 {
865         int i;
866         struct scpi_drvinfo *info = platform_get_drvdata(pdev);
867
868         scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
869
870         for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
871                 kfree(info->dvfs[i]->opps);
872                 kfree(info->dvfs[i]);
873         }
874
875         return 0;
876 }
877
878 #define MAX_SCPI_XFERS          10
879 static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
880 {
881         int i;
882         struct scpi_xfer *xfers;
883
884         xfers = devm_kcalloc(dev, MAX_SCPI_XFERS, sizeof(*xfers), GFP_KERNEL);
885         if (!xfers)
886                 return -ENOMEM;
887
888         ch->xfers = xfers;
889         for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++) {
890                 init_completion(&xfers->done);
891                 list_add_tail(&xfers->node, &ch->xfers_list);
892         }
893
894         return 0;
895 }
896
897 static const struct of_device_id legacy_scpi_of_match[] = {
898         {.compatible = "arm,scpi-pre-1.0"},
899         {},
900 };
901
902 static const struct of_device_id shmem_of_match[] __maybe_unused = {
903         { .compatible = "amlogic,meson-gxbb-scp-shmem", },
904         { .compatible = "amlogic,meson-axg-scp-shmem", },
905         { .compatible = "arm,juno-scp-shmem", },
906         { .compatible = "arm,scp-shmem", },
907         { }
908 };
909
910 static int scpi_probe(struct platform_device *pdev)
911 {
912         int count, idx, ret;
913         struct resource res;
914         struct device *dev = &pdev->dev;
915         struct device_node *np = dev->of_node;
916
917         scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
918         if (!scpi_info)
919                 return -ENOMEM;
920
921         if (of_match_device(legacy_scpi_of_match, &pdev->dev))
922                 scpi_info->is_legacy = true;
923
924         count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
925         if (count < 0) {
926                 dev_err(dev, "no mboxes property in '%pOF'\n", np);
927                 return -ENODEV;
928         }
929
930         scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
931                                            GFP_KERNEL);
932         if (!scpi_info->channels)
933                 return -ENOMEM;
934
935         ret = devm_add_action(dev, scpi_free_channels, scpi_info);
936         if (ret)
937                 return ret;
938
939         for (; scpi_info->num_chans < count; scpi_info->num_chans++) {
940                 resource_size_t size;
941                 int idx = scpi_info->num_chans;
942                 struct scpi_chan *pchan = scpi_info->channels + idx;
943                 struct mbox_client *cl = &pchan->cl;
944                 struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
945
946                 if (!of_match_node(shmem_of_match, shmem))
947                         return -ENXIO;
948
949                 ret = of_address_to_resource(shmem, 0, &res);
950                 of_node_put(shmem);
951                 if (ret) {
952                         dev_err(dev, "failed to get SCPI payload mem resource\n");
953                         return ret;
954                 }
955
956                 size = resource_size(&res);
957                 pchan->rx_payload = devm_ioremap(dev, res.start, size);
958                 if (!pchan->rx_payload) {
959                         dev_err(dev, "failed to ioremap SCPI payload\n");
960                         return -EADDRNOTAVAIL;
961                 }
962                 pchan->tx_payload = pchan->rx_payload + (size >> 1);
963
964                 cl->dev = dev;
965                 cl->rx_callback = scpi_handle_remote_msg;
966                 cl->tx_prepare = scpi_tx_prepare;
967                 cl->tx_block = true;
968                 cl->tx_tout = 20;
969                 cl->knows_txdone = false; /* controller can't ack */
970
971                 INIT_LIST_HEAD(&pchan->rx_pending);
972                 INIT_LIST_HEAD(&pchan->xfers_list);
973                 spin_lock_init(&pchan->rx_lock);
974                 mutex_init(&pchan->xfers_lock);
975
976                 ret = scpi_alloc_xfer_list(dev, pchan);
977                 if (!ret) {
978                         pchan->chan = mbox_request_channel(cl, idx);
979                         if (!IS_ERR(pchan->chan))
980                                 continue;
981                         ret = PTR_ERR(pchan->chan);
982                         if (ret != -EPROBE_DEFER)
983                                 dev_err(dev, "failed to get channel%d err %d\n",
984                                         idx, ret);
985                 }
986                 return ret;
987         }
988
989         scpi_info->commands = scpi_std_commands;
990
991         platform_set_drvdata(pdev, scpi_info);
992
993         if (scpi_info->is_legacy) {
994                 /* Replace with legacy variants */
995                 scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
996                 scpi_info->commands = scpi_legacy_commands;
997
998                 /* Fill priority bitmap */
999                 for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
1000                         set_bit(legacy_hpriority_cmds[idx],
1001                                 scpi_info->cmd_priority);
1002         }
1003
1004         ret = scpi_init_versions(scpi_info);
1005         if (ret) {
1006                 dev_err(dev, "incorrect or no SCP firmware found\n");
1007                 return ret;
1008         }
1009
1010         if (scpi_info->is_legacy && !scpi_info->protocol_version &&
1011             !scpi_info->firmware_version)
1012                 dev_info(dev, "SCP Protocol legacy pre-1.0 firmware\n");
1013         else
1014                 dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
1015                          FIELD_GET(PROTO_REV_MAJOR_MASK,
1016                                    scpi_info->protocol_version),
1017                          FIELD_GET(PROTO_REV_MINOR_MASK,
1018                                    scpi_info->protocol_version),
1019                          FIELD_GET(FW_REV_MAJOR_MASK,
1020                                    scpi_info->firmware_version),
1021                          FIELD_GET(FW_REV_MINOR_MASK,
1022                                    scpi_info->firmware_version),
1023                          FIELD_GET(FW_REV_PATCH_MASK,
1024                                    scpi_info->firmware_version));
1025         scpi_info->scpi_ops = &scpi_ops;
1026
1027         return devm_of_platform_populate(dev);
1028 }
1029
1030 static const struct of_device_id scpi_of_match[] = {
1031         {.compatible = "arm,scpi"},
1032         {.compatible = "arm,scpi-pre-1.0"},
1033         {},
1034 };
1035
1036 MODULE_DEVICE_TABLE(of, scpi_of_match);
1037
1038 static struct platform_driver scpi_driver = {
1039         .driver = {
1040                 .name = "scpi_protocol",
1041                 .of_match_table = scpi_of_match,
1042                 .dev_groups = versions_groups,
1043         },
1044         .probe = scpi_probe,
1045         .remove = scpi_remove,
1046 };
1047 module_platform_driver(scpi_driver);
1048
1049 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1050 MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1051 MODULE_LICENSE("GPL v2");