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