platform/x86: intel_mid_powerbtn: Use SCU IPC directly
[linux-2.6-microblaze.git] / drivers / firmware / arm_scpi.c
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 CMD_LEGACY_DATA_SIZE_SHIFT      20
54 #define CMD_LEGACY_DATA_SIZE_MASK       0x1ff
55 #define PACK_SCPI_CMD(cmd_id, tx_sz)                    \
56         ((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) |   \
57         (((tx_sz) & CMD_DATA_SIZE_MASK) << CMD_DATA_SIZE_SHIFT))
58 #define ADD_SCPI_TOKEN(cmd, token)                      \
59         ((cmd) |= (((token) & CMD_TOKEN_ID_MASK) << CMD_TOKEN_ID_SHIFT))
60 #define PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz)                             \
61         ((((cmd_id) & CMD_ID_MASK) << CMD_ID_SHIFT) |                          \
62         (((tx_sz) & CMD_LEGACY_DATA_SIZE_MASK) << CMD_LEGACY_DATA_SIZE_SHIFT))
63
64 #define CMD_SIZE(cmd)   (((cmd) >> CMD_DATA_SIZE_SHIFT) & CMD_DATA_SIZE_MASK)
65 #define CMD_LEGACY_SIZE(cmd)    (((cmd) >> CMD_LEGACY_DATA_SIZE_SHIFT) & \
66                                         CMD_LEGACY_DATA_SIZE_MASK)
67 #define CMD_UNIQ_MASK   (CMD_TOKEN_ID_MASK << CMD_TOKEN_ID_SHIFT | CMD_ID_MASK)
68 #define CMD_XTRACT_UNIQ(cmd)    ((cmd) & CMD_UNIQ_MASK)
69
70 #define SCPI_SLOT               0
71
72 #define MAX_DVFS_DOMAINS        8
73 #define MAX_DVFS_OPPS           16
74 #define DVFS_LATENCY(hdr)       (le32_to_cpu(hdr) >> 16)
75 #define DVFS_OPP_COUNT(hdr)     ((le32_to_cpu(hdr) >> 8) & 0xff)
76
77 #define PROTOCOL_REV_MINOR_BITS 16
78 #define PROTOCOL_REV_MINOR_MASK ((1U << PROTOCOL_REV_MINOR_BITS) - 1)
79 #define PROTOCOL_REV_MAJOR(x)   ((x) >> PROTOCOL_REV_MINOR_BITS)
80 #define PROTOCOL_REV_MINOR(x)   ((x) & PROTOCOL_REV_MINOR_MASK)
81
82 #define FW_REV_MAJOR_BITS       24
83 #define FW_REV_MINOR_BITS       16
84 #define FW_REV_PATCH_MASK       ((1U << FW_REV_MINOR_BITS) - 1)
85 #define FW_REV_MINOR_MASK       ((1U << FW_REV_MAJOR_BITS) - 1)
86 #define FW_REV_MAJOR(x)         ((x) >> FW_REV_MAJOR_BITS)
87 #define FW_REV_MINOR(x)         (((x) & FW_REV_MINOR_MASK) >> FW_REV_MINOR_BITS)
88 #define FW_REV_PATCH(x)         ((x) & FW_REV_PATCH_MASK)
89
90 #define MAX_RX_TIMEOUT          (msecs_to_jiffies(30))
91
92 enum scpi_error_codes {
93         SCPI_SUCCESS = 0, /* Success */
94         SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
95         SCPI_ERR_ALIGN = 2, /* Invalid alignment */
96         SCPI_ERR_SIZE = 3, /* Invalid size */
97         SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
98         SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
99         SCPI_ERR_RANGE = 6, /* Value out of range */
100         SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
101         SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
102         SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
103         SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
104         SCPI_ERR_DEVICE = 11, /* Device error */
105         SCPI_ERR_BUSY = 12, /* Device busy */
106         SCPI_ERR_MAX
107 };
108
109 /* SCPI Standard commands */
110 enum scpi_std_cmd {
111         SCPI_CMD_INVALID                = 0x00,
112         SCPI_CMD_SCPI_READY             = 0x01,
113         SCPI_CMD_SCPI_CAPABILITIES      = 0x02,
114         SCPI_CMD_SET_CSS_PWR_STATE      = 0x03,
115         SCPI_CMD_GET_CSS_PWR_STATE      = 0x04,
116         SCPI_CMD_SET_SYS_PWR_STATE      = 0x05,
117         SCPI_CMD_SET_CPU_TIMER          = 0x06,
118         SCPI_CMD_CANCEL_CPU_TIMER       = 0x07,
119         SCPI_CMD_DVFS_CAPABILITIES      = 0x08,
120         SCPI_CMD_GET_DVFS_INFO          = 0x09,
121         SCPI_CMD_SET_DVFS               = 0x0a,
122         SCPI_CMD_GET_DVFS               = 0x0b,
123         SCPI_CMD_GET_DVFS_STAT          = 0x0c,
124         SCPI_CMD_CLOCK_CAPABILITIES     = 0x0d,
125         SCPI_CMD_GET_CLOCK_INFO         = 0x0e,
126         SCPI_CMD_SET_CLOCK_VALUE        = 0x0f,
127         SCPI_CMD_GET_CLOCK_VALUE        = 0x10,
128         SCPI_CMD_PSU_CAPABILITIES       = 0x11,
129         SCPI_CMD_GET_PSU_INFO           = 0x12,
130         SCPI_CMD_SET_PSU                = 0x13,
131         SCPI_CMD_GET_PSU                = 0x14,
132         SCPI_CMD_SENSOR_CAPABILITIES    = 0x15,
133         SCPI_CMD_SENSOR_INFO            = 0x16,
134         SCPI_CMD_SENSOR_VALUE           = 0x17,
135         SCPI_CMD_SENSOR_CFG_PERIODIC    = 0x18,
136         SCPI_CMD_SENSOR_CFG_BOUNDS      = 0x19,
137         SCPI_CMD_SENSOR_ASYNC_VALUE     = 0x1a,
138         SCPI_CMD_SET_DEVICE_PWR_STATE   = 0x1b,
139         SCPI_CMD_GET_DEVICE_PWR_STATE   = 0x1c,
140         SCPI_CMD_COUNT
141 };
142
143 /* SCPI Legacy Commands */
144 enum legacy_scpi_std_cmd {
145         LEGACY_SCPI_CMD_INVALID                 = 0x00,
146         LEGACY_SCPI_CMD_SCPI_READY              = 0x01,
147         LEGACY_SCPI_CMD_SCPI_CAPABILITIES       = 0x02,
148         LEGACY_SCPI_CMD_EVENT                   = 0x03,
149         LEGACY_SCPI_CMD_SET_CSS_PWR_STATE       = 0x04,
150         LEGACY_SCPI_CMD_GET_CSS_PWR_STATE       = 0x05,
151         LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT      = 0x06,
152         LEGACY_SCPI_CMD_GET_PWR_STATE_STAT      = 0x07,
153         LEGACY_SCPI_CMD_SYS_PWR_STATE           = 0x08,
154         LEGACY_SCPI_CMD_L2_READY                = 0x09,
155         LEGACY_SCPI_CMD_SET_AP_TIMER            = 0x0a,
156         LEGACY_SCPI_CMD_CANCEL_AP_TIME          = 0x0b,
157         LEGACY_SCPI_CMD_DVFS_CAPABILITIES       = 0x0c,
158         LEGACY_SCPI_CMD_GET_DVFS_INFO           = 0x0d,
159         LEGACY_SCPI_CMD_SET_DVFS                = 0x0e,
160         LEGACY_SCPI_CMD_GET_DVFS                = 0x0f,
161         LEGACY_SCPI_CMD_GET_DVFS_STAT           = 0x10,
162         LEGACY_SCPI_CMD_SET_RTC                 = 0x11,
163         LEGACY_SCPI_CMD_GET_RTC                 = 0x12,
164         LEGACY_SCPI_CMD_CLOCK_CAPABILITIES      = 0x13,
165         LEGACY_SCPI_CMD_SET_CLOCK_INDEX         = 0x14,
166         LEGACY_SCPI_CMD_SET_CLOCK_VALUE         = 0x15,
167         LEGACY_SCPI_CMD_GET_CLOCK_VALUE         = 0x16,
168         LEGACY_SCPI_CMD_PSU_CAPABILITIES        = 0x17,
169         LEGACY_SCPI_CMD_SET_PSU                 = 0x18,
170         LEGACY_SCPI_CMD_GET_PSU                 = 0x19,
171         LEGACY_SCPI_CMD_SENSOR_CAPABILITIES     = 0x1a,
172         LEGACY_SCPI_CMD_SENSOR_INFO             = 0x1b,
173         LEGACY_SCPI_CMD_SENSOR_VALUE            = 0x1c,
174         LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC     = 0x1d,
175         LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS       = 0x1e,
176         LEGACY_SCPI_CMD_SENSOR_ASYNC_VALUE      = 0x1f,
177         LEGACY_SCPI_CMD_COUNT
178 };
179
180 /* List all commands that are required to go through the high priority link */
181 static int legacy_hpriority_cmds[] = {
182         LEGACY_SCPI_CMD_GET_CSS_PWR_STATE,
183         LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT,
184         LEGACY_SCPI_CMD_GET_PWR_STATE_STAT,
185         LEGACY_SCPI_CMD_SET_DVFS,
186         LEGACY_SCPI_CMD_GET_DVFS,
187         LEGACY_SCPI_CMD_SET_RTC,
188         LEGACY_SCPI_CMD_GET_RTC,
189         LEGACY_SCPI_CMD_SET_CLOCK_INDEX,
190         LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
191         LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
192         LEGACY_SCPI_CMD_SET_PSU,
193         LEGACY_SCPI_CMD_GET_PSU,
194         LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC,
195         LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS,
196 };
197
198 /* List all commands used by this driver, used as indexes */
199 enum scpi_drv_cmds {
200         CMD_SCPI_CAPABILITIES = 0,
201         CMD_GET_CLOCK_INFO,
202         CMD_GET_CLOCK_VALUE,
203         CMD_SET_CLOCK_VALUE,
204         CMD_GET_DVFS,
205         CMD_SET_DVFS,
206         CMD_GET_DVFS_INFO,
207         CMD_SENSOR_CAPABILITIES,
208         CMD_SENSOR_INFO,
209         CMD_SENSOR_VALUE,
210         CMD_SET_DEVICE_PWR_STATE,
211         CMD_GET_DEVICE_PWR_STATE,
212         CMD_MAX_COUNT,
213 };
214
215 static int scpi_std_commands[CMD_MAX_COUNT] = {
216         SCPI_CMD_SCPI_CAPABILITIES,
217         SCPI_CMD_GET_CLOCK_INFO,
218         SCPI_CMD_GET_CLOCK_VALUE,
219         SCPI_CMD_SET_CLOCK_VALUE,
220         SCPI_CMD_GET_DVFS,
221         SCPI_CMD_SET_DVFS,
222         SCPI_CMD_GET_DVFS_INFO,
223         SCPI_CMD_SENSOR_CAPABILITIES,
224         SCPI_CMD_SENSOR_INFO,
225         SCPI_CMD_SENSOR_VALUE,
226         SCPI_CMD_SET_DEVICE_PWR_STATE,
227         SCPI_CMD_GET_DEVICE_PWR_STATE,
228 };
229
230 static int scpi_legacy_commands[CMD_MAX_COUNT] = {
231         LEGACY_SCPI_CMD_SCPI_CAPABILITIES,
232         -1, /* GET_CLOCK_INFO */
233         LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
234         LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
235         LEGACY_SCPI_CMD_GET_DVFS,
236         LEGACY_SCPI_CMD_SET_DVFS,
237         LEGACY_SCPI_CMD_GET_DVFS_INFO,
238         LEGACY_SCPI_CMD_SENSOR_CAPABILITIES,
239         LEGACY_SCPI_CMD_SENSOR_INFO,
240         LEGACY_SCPI_CMD_SENSOR_VALUE,
241         -1, /* SET_DEVICE_PWR_STATE */
242         -1, /* GET_DEVICE_PWR_STATE */
243 };
244
245 struct scpi_xfer {
246         u32 slot; /* has to be first element */
247         u32 cmd;
248         u32 status;
249         const void *tx_buf;
250         void *rx_buf;
251         unsigned int tx_len;
252         unsigned int rx_len;
253         struct list_head node;
254         struct completion done;
255 };
256
257 struct scpi_chan {
258         struct mbox_client cl;
259         struct mbox_chan *chan;
260         void __iomem *tx_payload;
261         void __iomem *rx_payload;
262         struct list_head rx_pending;
263         struct list_head xfers_list;
264         struct scpi_xfer *xfers;
265         spinlock_t rx_lock; /* locking for the rx pending list */
266         struct mutex xfers_lock;
267         u8 token;
268 };
269
270 struct scpi_drvinfo {
271         u32 protocol_version;
272         u32 firmware_version;
273         bool is_legacy;
274         int num_chans;
275         int *commands;
276         DECLARE_BITMAP(cmd_priority, LEGACY_SCPI_CMD_COUNT);
277         atomic_t next_chan;
278         struct scpi_ops *scpi_ops;
279         struct scpi_chan *channels;
280         struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
281 };
282
283 /*
284  * The SCP firmware only executes in little-endian mode, so any buffers
285  * shared through SCPI should have their contents converted to little-endian
286  */
287 struct scpi_shared_mem {
288         __le32 command;
289         __le32 status;
290         u8 payload[0];
291 } __packed;
292
293 struct legacy_scpi_shared_mem {
294         __le32 status;
295         u8 payload[0];
296 } __packed;
297
298 struct scp_capabilities {
299         __le32 protocol_version;
300         __le32 event_version;
301         __le32 platform_version;
302         __le32 commands[4];
303 } __packed;
304
305 struct clk_get_info {
306         __le16 id;
307         __le16 flags;
308         __le32 min_rate;
309         __le32 max_rate;
310         u8 name[20];
311 } __packed;
312
313 struct clk_get_value {
314         __le32 rate;
315 } __packed;
316
317 struct clk_set_value {
318         __le16 id;
319         __le16 reserved;
320         __le32 rate;
321 } __packed;
322
323 struct legacy_clk_set_value {
324         __le32 rate;
325         __le16 id;
326         __le16 reserved;
327 } __packed;
328
329 struct dvfs_info {
330         __le32 header;
331         struct {
332                 __le32 freq;
333                 __le32 m_volt;
334         } opps[MAX_DVFS_OPPS];
335 } __packed;
336
337 struct dvfs_set {
338         u8 domain;
339         u8 index;
340 } __packed;
341
342 struct sensor_capabilities {
343         __le16 sensors;
344 } __packed;
345
346 struct _scpi_sensor_info {
347         __le16 sensor_id;
348         u8 class;
349         u8 trigger_type;
350         char name[20];
351 };
352
353 struct sensor_value {
354         __le32 lo_val;
355         __le32 hi_val;
356 } __packed;
357
358 struct dev_pstate_set {
359         u16 dev_id;
360         u8 pstate;
361 } __packed;
362
363 static struct scpi_drvinfo *scpi_info;
364
365 static int scpi_linux_errmap[SCPI_ERR_MAX] = {
366         /* better than switch case as long as return value is continuous */
367         0, /* SCPI_SUCCESS */
368         -EINVAL, /* SCPI_ERR_PARAM */
369         -ENOEXEC, /* SCPI_ERR_ALIGN */
370         -EMSGSIZE, /* SCPI_ERR_SIZE */
371         -EINVAL, /* SCPI_ERR_HANDLER */
372         -EACCES, /* SCPI_ERR_ACCESS */
373         -ERANGE, /* SCPI_ERR_RANGE */
374         -ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
375         -ENOMEM, /* SCPI_ERR_NOMEM */
376         -EINVAL, /* SCPI_ERR_PWRSTATE */
377         -EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
378         -EIO, /* SCPI_ERR_DEVICE */
379         -EBUSY, /* SCPI_ERR_BUSY */
380 };
381
382 static inline int scpi_to_linux_errno(int errno)
383 {
384         if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
385                 return scpi_linux_errmap[errno];
386         return -EIO;
387 }
388
389 static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
390 {
391         unsigned long flags;
392         struct scpi_xfer *t, *match = NULL;
393
394         spin_lock_irqsave(&ch->rx_lock, flags);
395         if (list_empty(&ch->rx_pending)) {
396                 spin_unlock_irqrestore(&ch->rx_lock, flags);
397                 return;
398         }
399
400         /* Command type is not replied by the SCP Firmware in legacy Mode
401          * We should consider that command is the head of pending RX commands
402          * if the list is not empty. In TX only mode, the list would be empty.
403          */
404         if (scpi_info->is_legacy) {
405                 match = list_first_entry(&ch->rx_pending, struct scpi_xfer,
406                                          node);
407                 list_del(&match->node);
408         } else {
409                 list_for_each_entry(t, &ch->rx_pending, node)
410                         if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
411                                 list_del(&t->node);
412                                 match = t;
413                                 break;
414                         }
415         }
416         /* check if wait_for_completion is in progress or timed-out */
417         if (match && !completion_done(&match->done)) {
418                 unsigned int len;
419
420                 if (scpi_info->is_legacy) {
421                         struct legacy_scpi_shared_mem *mem = ch->rx_payload;
422
423                         /* RX Length is not replied by the legacy Firmware */
424                         len = match->rx_len;
425
426                         match->status = le32_to_cpu(mem->status);
427                         memcpy_fromio(match->rx_buf, mem->payload, len);
428                 } else {
429                         struct scpi_shared_mem *mem = ch->rx_payload;
430
431                         len = min(match->rx_len, CMD_SIZE(cmd));
432
433                         match->status = le32_to_cpu(mem->status);
434                         memcpy_fromio(match->rx_buf, mem->payload, len);
435                 }
436
437                 if (match->rx_len > len)
438                         memset(match->rx_buf + len, 0, match->rx_len - len);
439                 complete(&match->done);
440         }
441         spin_unlock_irqrestore(&ch->rx_lock, flags);
442 }
443
444 static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
445 {
446         struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
447         struct scpi_shared_mem *mem = ch->rx_payload;
448         u32 cmd = 0;
449
450         if (!scpi_info->is_legacy)
451                 cmd = le32_to_cpu(mem->command);
452
453         scpi_process_cmd(ch, cmd);
454 }
455
456 static void scpi_tx_prepare(struct mbox_client *c, void *msg)
457 {
458         unsigned long flags;
459         struct scpi_xfer *t = msg;
460         struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
461         struct scpi_shared_mem *mem = (struct scpi_shared_mem *)ch->tx_payload;
462
463         if (t->tx_buf) {
464                 if (scpi_info->is_legacy)
465                         memcpy_toio(ch->tx_payload, t->tx_buf, t->tx_len);
466                 else
467                         memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
468         }
469
470         if (t->rx_buf) {
471                 if (!(++ch->token))
472                         ++ch->token;
473                 ADD_SCPI_TOKEN(t->cmd, ch->token);
474                 spin_lock_irqsave(&ch->rx_lock, flags);
475                 list_add_tail(&t->node, &ch->rx_pending);
476                 spin_unlock_irqrestore(&ch->rx_lock, flags);
477         }
478
479         if (!scpi_info->is_legacy)
480                 mem->command = cpu_to_le32(t->cmd);
481 }
482
483 static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
484 {
485         struct scpi_xfer *t;
486
487         mutex_lock(&ch->xfers_lock);
488         if (list_empty(&ch->xfers_list)) {
489                 mutex_unlock(&ch->xfers_lock);
490                 return NULL;
491         }
492         t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
493         list_del(&t->node);
494         mutex_unlock(&ch->xfers_lock);
495         return t;
496 }
497
498 static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
499 {
500         mutex_lock(&ch->xfers_lock);
501         list_add_tail(&t->node, &ch->xfers_list);
502         mutex_unlock(&ch->xfers_lock);
503 }
504
505 static int scpi_send_message(u8 idx, void *tx_buf, unsigned int tx_len,
506                              void *rx_buf, unsigned int rx_len)
507 {
508         int ret;
509         u8 chan;
510         u8 cmd;
511         struct scpi_xfer *msg;
512         struct scpi_chan *scpi_chan;
513
514         if (scpi_info->commands[idx] < 0)
515                 return -EOPNOTSUPP;
516
517         cmd = scpi_info->commands[idx];
518
519         if (scpi_info->is_legacy)
520                 chan = test_bit(cmd, scpi_info->cmd_priority) ? 1 : 0;
521         else
522                 chan = atomic_inc_return(&scpi_info->next_chan) %
523                         scpi_info->num_chans;
524         scpi_chan = scpi_info->channels + chan;
525
526         msg = get_scpi_xfer(scpi_chan);
527         if (!msg)
528                 return -ENOMEM;
529
530         if (scpi_info->is_legacy) {
531                 msg->cmd = PACK_LEGACY_SCPI_CMD(cmd, tx_len);
532                 msg->slot = msg->cmd;
533         } else {
534                 msg->slot = BIT(SCPI_SLOT);
535                 msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
536         }
537         msg->tx_buf = tx_buf;
538         msg->tx_len = tx_len;
539         msg->rx_buf = rx_buf;
540         msg->rx_len = rx_len;
541         init_completion(&msg->done);
542
543         ret = mbox_send_message(scpi_chan->chan, msg);
544         if (ret < 0 || !rx_buf)
545                 goto out;
546
547         if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
548                 ret = -ETIMEDOUT;
549         else
550                 /* first status word */
551                 ret = msg->status;
552 out:
553         if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
554                 scpi_process_cmd(scpi_chan, msg->cmd);
555
556         put_scpi_xfer(msg, scpi_chan);
557         /* SCPI error codes > 0, translate them to Linux scale*/
558         return ret > 0 ? scpi_to_linux_errno(ret) : ret;
559 }
560
561 static u32 scpi_get_version(void)
562 {
563         return scpi_info->protocol_version;
564 }
565
566 static int
567 scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
568 {
569         int ret;
570         struct clk_get_info clk;
571         __le16 le_clk_id = cpu_to_le16(clk_id);
572
573         ret = scpi_send_message(CMD_GET_CLOCK_INFO, &le_clk_id,
574                                 sizeof(le_clk_id), &clk, sizeof(clk));
575         if (!ret) {
576                 *min = le32_to_cpu(clk.min_rate);
577                 *max = le32_to_cpu(clk.max_rate);
578         }
579         return ret;
580 }
581
582 static unsigned long scpi_clk_get_val(u16 clk_id)
583 {
584         int ret;
585         struct clk_get_value clk;
586         __le16 le_clk_id = cpu_to_le16(clk_id);
587
588         ret = scpi_send_message(CMD_GET_CLOCK_VALUE, &le_clk_id,
589                                 sizeof(le_clk_id), &clk, sizeof(clk));
590
591         return ret ? ret : le32_to_cpu(clk.rate);
592 }
593
594 static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
595 {
596         int stat;
597         struct clk_set_value clk = {
598                 .id = cpu_to_le16(clk_id),
599                 .rate = cpu_to_le32(rate)
600         };
601
602         return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
603                                  &stat, sizeof(stat));
604 }
605
606 static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
607 {
608         int stat;
609         struct legacy_clk_set_value clk = {
610                 .id = cpu_to_le16(clk_id),
611                 .rate = cpu_to_le32(rate)
612         };
613
614         return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
615                                  &stat, sizeof(stat));
616 }
617
618 static int scpi_dvfs_get_idx(u8 domain)
619 {
620         int ret;
621         u8 dvfs_idx;
622
623         ret = scpi_send_message(CMD_GET_DVFS, &domain, sizeof(domain),
624                                 &dvfs_idx, sizeof(dvfs_idx));
625
626         return ret ? ret : dvfs_idx;
627 }
628
629 static int scpi_dvfs_set_idx(u8 domain, u8 index)
630 {
631         int stat;
632         struct dvfs_set dvfs = {domain, index};
633
634         return scpi_send_message(CMD_SET_DVFS, &dvfs, sizeof(dvfs),
635                                  &stat, sizeof(stat));
636 }
637
638 static int opp_cmp_func(const void *opp1, const void *opp2)
639 {
640         const struct scpi_opp *t1 = opp1, *t2 = opp2;
641
642         return t1->freq - t2->freq;
643 }
644
645 static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
646 {
647         struct scpi_dvfs_info *info;
648         struct scpi_opp *opp;
649         struct dvfs_info buf;
650         int ret, i;
651
652         if (domain >= MAX_DVFS_DOMAINS)
653                 return ERR_PTR(-EINVAL);
654
655         if (scpi_info->dvfs[domain])    /* data already populated */
656                 return scpi_info->dvfs[domain];
657
658         ret = scpi_send_message(CMD_GET_DVFS_INFO, &domain, sizeof(domain),
659                                 &buf, sizeof(buf));
660         if (ret)
661                 return ERR_PTR(ret);
662
663         info = kmalloc(sizeof(*info), GFP_KERNEL);
664         if (!info)
665                 return ERR_PTR(-ENOMEM);
666
667         info->count = DVFS_OPP_COUNT(buf.header);
668         info->latency = DVFS_LATENCY(buf.header) * 1000; /* uS to nS */
669
670         info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
671         if (!info->opps) {
672                 kfree(info);
673                 return ERR_PTR(-ENOMEM);
674         }
675
676         for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
677                 opp->freq = le32_to_cpu(buf.opps[i].freq);
678                 opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
679         }
680
681         sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
682
683         scpi_info->dvfs[domain] = info;
684         return info;
685 }
686
687 static int scpi_sensor_get_capability(u16 *sensors)
688 {
689         struct sensor_capabilities cap_buf;
690         int ret;
691
692         ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap_buf,
693                                 sizeof(cap_buf));
694         if (!ret)
695                 *sensors = le16_to_cpu(cap_buf.sensors);
696
697         return ret;
698 }
699
700 static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
701 {
702         __le16 id = cpu_to_le16(sensor_id);
703         struct _scpi_sensor_info _info;
704         int ret;
705
706         ret = scpi_send_message(CMD_SENSOR_INFO, &id, sizeof(id),
707                                 &_info, sizeof(_info));
708         if (!ret) {
709                 memcpy(info, &_info, sizeof(*info));
710                 info->sensor_id = le16_to_cpu(_info.sensor_id);
711         }
712
713         return ret;
714 }
715
716 static int scpi_sensor_get_value(u16 sensor, u64 *val)
717 {
718         __le16 id = cpu_to_le16(sensor);
719         struct sensor_value buf;
720         int ret;
721
722         ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
723                                 &buf, sizeof(buf));
724         if (ret)
725                 return ret;
726
727         if (scpi_info->is_legacy)
728                 /* only 32-bits supported, hi_val can be junk */
729                 *val = le32_to_cpu(buf.lo_val);
730         else
731                 *val = (u64)le32_to_cpu(buf.hi_val) << 32 |
732                         le32_to_cpu(buf.lo_val);
733
734         return 0;
735 }
736
737 static int scpi_device_get_power_state(u16 dev_id)
738 {
739         int ret;
740         u8 pstate;
741         __le16 id = cpu_to_le16(dev_id);
742
743         ret = scpi_send_message(CMD_GET_DEVICE_PWR_STATE, &id,
744                                 sizeof(id), &pstate, sizeof(pstate));
745         return ret ? ret : pstate;
746 }
747
748 static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
749 {
750         int stat;
751         struct dev_pstate_set dev_set = {
752                 .dev_id = cpu_to_le16(dev_id),
753                 .pstate = pstate,
754         };
755
756         return scpi_send_message(CMD_SET_DEVICE_PWR_STATE, &dev_set,
757                                  sizeof(dev_set), &stat, sizeof(stat));
758 }
759
760 static struct scpi_ops scpi_ops = {
761         .get_version = scpi_get_version,
762         .clk_get_range = scpi_clk_get_range,
763         .clk_get_val = scpi_clk_get_val,
764         .clk_set_val = scpi_clk_set_val,
765         .dvfs_get_idx = scpi_dvfs_get_idx,
766         .dvfs_set_idx = scpi_dvfs_set_idx,
767         .dvfs_get_info = scpi_dvfs_get_info,
768         .sensor_get_capability = scpi_sensor_get_capability,
769         .sensor_get_info = scpi_sensor_get_info,
770         .sensor_get_value = scpi_sensor_get_value,
771         .device_get_power_state = scpi_device_get_power_state,
772         .device_set_power_state = scpi_device_set_power_state,
773 };
774
775 struct scpi_ops *get_scpi_ops(void)
776 {
777         return scpi_info ? scpi_info->scpi_ops : NULL;
778 }
779 EXPORT_SYMBOL_GPL(get_scpi_ops);
780
781 static int scpi_init_versions(struct scpi_drvinfo *info)
782 {
783         int ret;
784         struct scp_capabilities caps;
785
786         ret = scpi_send_message(CMD_SCPI_CAPABILITIES, NULL, 0,
787                                 &caps, sizeof(caps));
788         if (!ret) {
789                 info->protocol_version = le32_to_cpu(caps.protocol_version);
790                 info->firmware_version = le32_to_cpu(caps.platform_version);
791         }
792         /* Ignore error if not implemented */
793         if (scpi_info->is_legacy && ret == -EOPNOTSUPP)
794                 return 0;
795
796         return ret;
797 }
798
799 static ssize_t protocol_version_show(struct device *dev,
800                                      struct device_attribute *attr, char *buf)
801 {
802         struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
803
804         return sprintf(buf, "%d.%d\n",
805                        PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
806                        PROTOCOL_REV_MINOR(scpi_info->protocol_version));
807 }
808 static DEVICE_ATTR_RO(protocol_version);
809
810 static ssize_t firmware_version_show(struct device *dev,
811                                      struct device_attribute *attr, char *buf)
812 {
813         struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
814
815         return sprintf(buf, "%d.%d.%d\n",
816                        FW_REV_MAJOR(scpi_info->firmware_version),
817                        FW_REV_MINOR(scpi_info->firmware_version),
818                        FW_REV_PATCH(scpi_info->firmware_version));
819 }
820 static DEVICE_ATTR_RO(firmware_version);
821
822 static struct attribute *versions_attrs[] = {
823         &dev_attr_firmware_version.attr,
824         &dev_attr_protocol_version.attr,
825         NULL,
826 };
827 ATTRIBUTE_GROUPS(versions);
828
829 static void
830 scpi_free_channels(struct device *dev, struct scpi_chan *pchan, int count)
831 {
832         int i;
833
834         for (i = 0; i < count && pchan->chan; i++, pchan++) {
835                 mbox_free_channel(pchan->chan);
836                 devm_kfree(dev, pchan->xfers);
837                 devm_iounmap(dev, pchan->rx_payload);
838         }
839 }
840
841 static int scpi_remove(struct platform_device *pdev)
842 {
843         int i;
844         struct device *dev = &pdev->dev;
845         struct scpi_drvinfo *info = platform_get_drvdata(pdev);
846
847         scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
848
849         of_platform_depopulate(dev);
850         sysfs_remove_groups(&dev->kobj, versions_groups);
851         scpi_free_channels(dev, info->channels, info->num_chans);
852         platform_set_drvdata(pdev, NULL);
853
854         for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
855                 kfree(info->dvfs[i]->opps);
856                 kfree(info->dvfs[i]);
857         }
858         devm_kfree(dev, info->channels);
859         devm_kfree(dev, info);
860
861         return 0;
862 }
863
864 #define MAX_SCPI_XFERS          10
865 static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
866 {
867         int i;
868         struct scpi_xfer *xfers;
869
870         xfers = devm_kzalloc(dev, MAX_SCPI_XFERS * sizeof(*xfers), GFP_KERNEL);
871         if (!xfers)
872                 return -ENOMEM;
873
874         ch->xfers = xfers;
875         for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++)
876                 list_add_tail(&xfers->node, &ch->xfers_list);
877         return 0;
878 }
879
880 static const struct of_device_id legacy_scpi_of_match[] = {
881         {.compatible = "arm,scpi-pre-1.0"},
882         {},
883 };
884
885 static int scpi_probe(struct platform_device *pdev)
886 {
887         int count, idx, ret;
888         struct resource res;
889         struct scpi_chan *scpi_chan;
890         struct device *dev = &pdev->dev;
891         struct device_node *np = dev->of_node;
892
893         scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
894         if (!scpi_info)
895                 return -ENOMEM;
896
897         if (of_match_device(legacy_scpi_of_match, &pdev->dev))
898                 scpi_info->is_legacy = true;
899
900         count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
901         if (count < 0) {
902                 dev_err(dev, "no mboxes property in '%s'\n", np->full_name);
903                 return -ENODEV;
904         }
905
906         scpi_chan = devm_kcalloc(dev, count, sizeof(*scpi_chan), GFP_KERNEL);
907         if (!scpi_chan)
908                 return -ENOMEM;
909
910         for (idx = 0; idx < count; idx++) {
911                 resource_size_t size;
912                 struct scpi_chan *pchan = scpi_chan + idx;
913                 struct mbox_client *cl = &pchan->cl;
914                 struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
915
916                 ret = of_address_to_resource(shmem, 0, &res);
917                 of_node_put(shmem);
918                 if (ret) {
919                         dev_err(dev, "failed to get SCPI payload mem resource\n");
920                         goto err;
921                 }
922
923                 size = resource_size(&res);
924                 pchan->rx_payload = devm_ioremap(dev, res.start, size);
925                 if (!pchan->rx_payload) {
926                         dev_err(dev, "failed to ioremap SCPI payload\n");
927                         ret = -EADDRNOTAVAIL;
928                         goto err;
929                 }
930                 pchan->tx_payload = pchan->rx_payload + (size >> 1);
931
932                 cl->dev = dev;
933                 cl->rx_callback = scpi_handle_remote_msg;
934                 cl->tx_prepare = scpi_tx_prepare;
935                 cl->tx_block = true;
936                 cl->tx_tout = 20;
937                 cl->knows_txdone = false; /* controller can't ack */
938
939                 INIT_LIST_HEAD(&pchan->rx_pending);
940                 INIT_LIST_HEAD(&pchan->xfers_list);
941                 spin_lock_init(&pchan->rx_lock);
942                 mutex_init(&pchan->xfers_lock);
943
944                 ret = scpi_alloc_xfer_list(dev, pchan);
945                 if (!ret) {
946                         pchan->chan = mbox_request_channel(cl, idx);
947                         if (!IS_ERR(pchan->chan))
948                                 continue;
949                         ret = PTR_ERR(pchan->chan);
950                         if (ret != -EPROBE_DEFER)
951                                 dev_err(dev, "failed to get channel%d err %d\n",
952                                         idx, ret);
953                 }
954 err:
955                 scpi_free_channels(dev, scpi_chan, idx);
956                 scpi_info = NULL;
957                 return ret;
958         }
959
960         scpi_info->channels = scpi_chan;
961         scpi_info->num_chans = count;
962         scpi_info->commands = scpi_std_commands;
963
964         platform_set_drvdata(pdev, scpi_info);
965
966         if (scpi_info->is_legacy) {
967                 /* Replace with legacy variants */
968                 scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
969                 scpi_info->commands = scpi_legacy_commands;
970
971                 /* Fill priority bitmap */
972                 for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
973                         set_bit(legacy_hpriority_cmds[idx],
974                                 scpi_info->cmd_priority);
975         }
976
977         ret = scpi_init_versions(scpi_info);
978         if (ret) {
979                 dev_err(dev, "incorrect or no SCP firmware found\n");
980                 scpi_remove(pdev);
981                 return ret;
982         }
983
984         _dev_info(dev, "SCP Protocol %d.%d Firmware %d.%d.%d version\n",
985                   PROTOCOL_REV_MAJOR(scpi_info->protocol_version),
986                   PROTOCOL_REV_MINOR(scpi_info->protocol_version),
987                   FW_REV_MAJOR(scpi_info->firmware_version),
988                   FW_REV_MINOR(scpi_info->firmware_version),
989                   FW_REV_PATCH(scpi_info->firmware_version));
990         scpi_info->scpi_ops = &scpi_ops;
991
992         ret = sysfs_create_groups(&dev->kobj, versions_groups);
993         if (ret)
994                 dev_err(dev, "unable to create sysfs version group\n");
995
996         return of_platform_populate(dev->of_node, NULL, NULL, dev);
997 }
998
999 static const struct of_device_id scpi_of_match[] = {
1000         {.compatible = "arm,scpi"},
1001         {.compatible = "arm,scpi-pre-1.0"},
1002         {},
1003 };
1004
1005 MODULE_DEVICE_TABLE(of, scpi_of_match);
1006
1007 static struct platform_driver scpi_driver = {
1008         .driver = {
1009                 .name = "scpi_protocol",
1010                 .of_match_table = scpi_of_match,
1011         },
1012         .probe = scpi_probe,
1013         .remove = scpi_remove,
1014 };
1015 module_platform_driver(scpi_driver);
1016
1017 MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1018 MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1019 MODULE_LICENSE("GPL v2");