Linux Audio

Check our new training course

Loading...
v6.8
   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
  70enum 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 */
  88enum 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 */
 122enum 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 */
 159static 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 */
 177enum 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
 193static 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
 208static 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
 223struct 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
 235struct 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
 248struct 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 */
 265struct scpi_shared_mem {
 266	__le32 command;
 267	__le32 status;
 268	u8 payload[];
 269} __packed;
 270
 271struct legacy_scpi_shared_mem {
 272	__le32 status;
 273	u8 payload[];
 274} __packed;
 275
 276struct scp_capabilities {
 277	__le32 protocol_version;
 278	__le32 event_version;
 279	__le32 platform_version;
 280	__le32 commands[4];
 281} __packed;
 282
 283struct clk_get_info {
 284	__le16 id;
 285	__le16 flags;
 286	__le32 min_rate;
 287	__le32 max_rate;
 288	u8 name[20];
 289} __packed;
 290
 291struct clk_set_value {
 292	__le16 id;
 293	__le16 reserved;
 294	__le32 rate;
 295} __packed;
 296
 297struct legacy_clk_set_value {
 298	__le32 rate;
 299	__le16 id;
 300	__le16 reserved;
 301} __packed;
 302
 303struct 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
 313struct dvfs_set {
 314	u8 domain;
 315	u8 index;
 316} __packed;
 317
 318struct _scpi_sensor_info {
 319	__le16 sensor_id;
 320	u8 class;
 321	u8 trigger_type;
 322	char name[20];
 323};
 324
 325struct dev_pstate_set {
 326	__le16 dev_id;
 327	u8 pstate;
 328} __packed;
 329
 330static struct scpi_drvinfo *scpi_info;
 331
 332static 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
 349static 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
 356static 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
 412static 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
 424static 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
 451static 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
 466static 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
 473static 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;
 520out:
 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
 529static u32 scpi_get_version(void)
 530{
 531	return scpi_info->protocol_version;
 532}
 533
 534static int
 535scpi_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
 550static 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
 564static 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
 576static 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
 588static 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
 599static 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
 608static 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
 615static 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
 657static 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
 668static 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
 678static 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
 688static 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
 713static 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
 726static 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
 742static 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
 762static 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
 773static 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
 785static 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
 803struct scpi_ops *get_scpi_ops(void)
 804{
 805	return scpi_info ? scpi_info->scpi_ops : NULL;
 806}
 807EXPORT_SYMBOL_GPL(get_scpi_ops);
 808
 809static 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
 827static 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}
 836static DEVICE_ATTR_RO(protocol_version);
 837
 838static 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}
 848static DEVICE_ATTR_RO(firmware_version);
 849
 850static struct attribute *versions_attrs[] = {
 851	&dev_attr_firmware_version.attr,
 852	&dev_attr_protocol_version.attr,
 853	NULL,
 854};
 855ATTRIBUTE_GROUPS(versions);
 856
 857static 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
 866static 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
 880static 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
 898static 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
 906static 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
1034static 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
1040MODULE_DEVICE_TABLE(of, scpi_of_match);
1041
1042static 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};
1051module_platform_driver(scpi_driver);
1052
1053MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1054MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1055MODULE_LICENSE("GPL v2");
v4.17
 
   1/*
   2 * System Control and Power Interface (SCPI) Message Protocol driver
   3 *
   4 * SCPI Message Protocol is used between the System Control Processor(SCP)
   5 * and the Application Processors(AP). The Message Handling Unit(MHU)
   6 * provides a mechanism for inter-processor communication between SCP's
   7 * Cortex M3 and AP.
   8 *
   9 * SCP offers control and management of the core/cluster power states,
  10 * various power domain DVFS including the core/cluster, certain system
  11 * clocks configuration, thermal sensors and many others.
  12 *
  13 * Copyright (C) 2015 ARM Ltd.
  14 *
  15 * This program is free software; you can redistribute it and/or modify it
  16 * under the terms and conditions of the GNU General Public License,
  17 * version 2, as published by the Free Software Foundation.
  18 *
  19 * This program is distributed in the hope it will be useful, but WITHOUT
  20 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  21 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  22 * more details.
  23 *
  24 * You should have received a copy of the GNU General Public License along
  25 * with this program. If not, see <http://www.gnu.org/licenses/>.
  26 */
  27
  28#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  29
  30#include <linux/bitmap.h>
  31#include <linux/bitfield.h>
  32#include <linux/device.h>
  33#include <linux/err.h>
  34#include <linux/export.h>
  35#include <linux/io.h>
  36#include <linux/kernel.h>
  37#include <linux/list.h>
  38#include <linux/mailbox_client.h>
  39#include <linux/module.h>
 
  40#include <linux/of_address.h>
  41#include <linux/of_platform.h>
 
  42#include <linux/printk.h>
 
  43#include <linux/pm_opp.h>
  44#include <linux/scpi_protocol.h>
  45#include <linux/slab.h>
  46#include <linux/sort.h>
  47#include <linux/spinlock.h>
  48
  49#define CMD_ID_MASK		GENMASK(6, 0)
  50#define CMD_TOKEN_ID_MASK	GENMASK(15, 8)
  51#define CMD_DATA_SIZE_MASK	GENMASK(24, 16)
  52#define CMD_LEGACY_DATA_SIZE_MASK	GENMASK(28, 20)
  53#define PACK_SCPI_CMD(cmd_id, tx_sz)		\
  54	(FIELD_PREP(CMD_ID_MASK, cmd_id) |	\
  55	FIELD_PREP(CMD_DATA_SIZE_MASK, tx_sz))
  56#define PACK_LEGACY_SCPI_CMD(cmd_id, tx_sz)	\
  57	(FIELD_PREP(CMD_ID_MASK, cmd_id) |	\
  58	FIELD_PREP(CMD_LEGACY_DATA_SIZE_MASK, tx_sz))
  59
  60#define CMD_SIZE(cmd)	FIELD_GET(CMD_DATA_SIZE_MASK, cmd)
  61#define CMD_UNIQ_MASK	(CMD_TOKEN_ID_MASK | CMD_ID_MASK)
  62#define CMD_XTRACT_UNIQ(cmd)	((cmd) & CMD_UNIQ_MASK)
  63
  64#define SCPI_SLOT		0
  65
  66#define MAX_DVFS_DOMAINS	8
  67#define MAX_DVFS_OPPS		16
  68
  69#define PROTO_REV_MAJOR_MASK	GENMASK(31, 16)
  70#define PROTO_REV_MINOR_MASK	GENMASK(15, 0)
  71
  72#define FW_REV_MAJOR_MASK	GENMASK(31, 24)
  73#define FW_REV_MINOR_MASK	GENMASK(23, 16)
  74#define FW_REV_PATCH_MASK	GENMASK(15, 0)
  75
  76#define MAX_RX_TIMEOUT		(msecs_to_jiffies(30))
  77
  78enum scpi_error_codes {
  79	SCPI_SUCCESS = 0, /* Success */
  80	SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */
  81	SCPI_ERR_ALIGN = 2, /* Invalid alignment */
  82	SCPI_ERR_SIZE = 3, /* Invalid size */
  83	SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */
  84	SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */
  85	SCPI_ERR_RANGE = 6, /* Value out of range */
  86	SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */
  87	SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */
  88	SCPI_ERR_PWRSTATE = 9, /* Invalid power state */
  89	SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */
  90	SCPI_ERR_DEVICE = 11, /* Device error */
  91	SCPI_ERR_BUSY = 12, /* Device busy */
  92	SCPI_ERR_MAX
  93};
  94
  95/* SCPI Standard commands */
  96enum scpi_std_cmd {
  97	SCPI_CMD_INVALID		= 0x00,
  98	SCPI_CMD_SCPI_READY		= 0x01,
  99	SCPI_CMD_SCPI_CAPABILITIES	= 0x02,
 100	SCPI_CMD_SET_CSS_PWR_STATE	= 0x03,
 101	SCPI_CMD_GET_CSS_PWR_STATE	= 0x04,
 102	SCPI_CMD_SET_SYS_PWR_STATE	= 0x05,
 103	SCPI_CMD_SET_CPU_TIMER		= 0x06,
 104	SCPI_CMD_CANCEL_CPU_TIMER	= 0x07,
 105	SCPI_CMD_DVFS_CAPABILITIES	= 0x08,
 106	SCPI_CMD_GET_DVFS_INFO		= 0x09,
 107	SCPI_CMD_SET_DVFS		= 0x0a,
 108	SCPI_CMD_GET_DVFS		= 0x0b,
 109	SCPI_CMD_GET_DVFS_STAT		= 0x0c,
 110	SCPI_CMD_CLOCK_CAPABILITIES	= 0x0d,
 111	SCPI_CMD_GET_CLOCK_INFO		= 0x0e,
 112	SCPI_CMD_SET_CLOCK_VALUE	= 0x0f,
 113	SCPI_CMD_GET_CLOCK_VALUE	= 0x10,
 114	SCPI_CMD_PSU_CAPABILITIES	= 0x11,
 115	SCPI_CMD_GET_PSU_INFO		= 0x12,
 116	SCPI_CMD_SET_PSU		= 0x13,
 117	SCPI_CMD_GET_PSU		= 0x14,
 118	SCPI_CMD_SENSOR_CAPABILITIES	= 0x15,
 119	SCPI_CMD_SENSOR_INFO		= 0x16,
 120	SCPI_CMD_SENSOR_VALUE		= 0x17,
 121	SCPI_CMD_SENSOR_CFG_PERIODIC	= 0x18,
 122	SCPI_CMD_SENSOR_CFG_BOUNDS	= 0x19,
 123	SCPI_CMD_SENSOR_ASYNC_VALUE	= 0x1a,
 124	SCPI_CMD_SET_DEVICE_PWR_STATE	= 0x1b,
 125	SCPI_CMD_GET_DEVICE_PWR_STATE	= 0x1c,
 126	SCPI_CMD_COUNT
 127};
 128
 129/* SCPI Legacy Commands */
 130enum legacy_scpi_std_cmd {
 131	LEGACY_SCPI_CMD_INVALID			= 0x00,
 132	LEGACY_SCPI_CMD_SCPI_READY		= 0x01,
 133	LEGACY_SCPI_CMD_SCPI_CAPABILITIES	= 0x02,
 134	LEGACY_SCPI_CMD_EVENT			= 0x03,
 135	LEGACY_SCPI_CMD_SET_CSS_PWR_STATE	= 0x04,
 136	LEGACY_SCPI_CMD_GET_CSS_PWR_STATE	= 0x05,
 137	LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT	= 0x06,
 138	LEGACY_SCPI_CMD_GET_PWR_STATE_STAT	= 0x07,
 139	LEGACY_SCPI_CMD_SYS_PWR_STATE		= 0x08,
 140	LEGACY_SCPI_CMD_L2_READY		= 0x09,
 141	LEGACY_SCPI_CMD_SET_AP_TIMER		= 0x0a,
 142	LEGACY_SCPI_CMD_CANCEL_AP_TIME		= 0x0b,
 143	LEGACY_SCPI_CMD_DVFS_CAPABILITIES	= 0x0c,
 144	LEGACY_SCPI_CMD_GET_DVFS_INFO		= 0x0d,
 145	LEGACY_SCPI_CMD_SET_DVFS		= 0x0e,
 146	LEGACY_SCPI_CMD_GET_DVFS		= 0x0f,
 147	LEGACY_SCPI_CMD_GET_DVFS_STAT		= 0x10,
 148	LEGACY_SCPI_CMD_SET_RTC			= 0x11,
 149	LEGACY_SCPI_CMD_GET_RTC			= 0x12,
 150	LEGACY_SCPI_CMD_CLOCK_CAPABILITIES	= 0x13,
 151	LEGACY_SCPI_CMD_SET_CLOCK_INDEX		= 0x14,
 152	LEGACY_SCPI_CMD_SET_CLOCK_VALUE		= 0x15,
 153	LEGACY_SCPI_CMD_GET_CLOCK_VALUE		= 0x16,
 154	LEGACY_SCPI_CMD_PSU_CAPABILITIES	= 0x17,
 155	LEGACY_SCPI_CMD_SET_PSU			= 0x18,
 156	LEGACY_SCPI_CMD_GET_PSU			= 0x19,
 157	LEGACY_SCPI_CMD_SENSOR_CAPABILITIES	= 0x1a,
 158	LEGACY_SCPI_CMD_SENSOR_INFO		= 0x1b,
 159	LEGACY_SCPI_CMD_SENSOR_VALUE		= 0x1c,
 160	LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC	= 0x1d,
 161	LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS	= 0x1e,
 162	LEGACY_SCPI_CMD_SENSOR_ASYNC_VALUE	= 0x1f,
 163	LEGACY_SCPI_CMD_COUNT
 164};
 165
 166/* List all commands that are required to go through the high priority link */
 167static int legacy_hpriority_cmds[] = {
 168	LEGACY_SCPI_CMD_GET_CSS_PWR_STATE,
 169	LEGACY_SCPI_CMD_CFG_PWR_STATE_STAT,
 170	LEGACY_SCPI_CMD_GET_PWR_STATE_STAT,
 171	LEGACY_SCPI_CMD_SET_DVFS,
 172	LEGACY_SCPI_CMD_GET_DVFS,
 173	LEGACY_SCPI_CMD_SET_RTC,
 174	LEGACY_SCPI_CMD_GET_RTC,
 175	LEGACY_SCPI_CMD_SET_CLOCK_INDEX,
 176	LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
 177	LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
 178	LEGACY_SCPI_CMD_SET_PSU,
 179	LEGACY_SCPI_CMD_GET_PSU,
 180	LEGACY_SCPI_CMD_SENSOR_CFG_PERIODIC,
 181	LEGACY_SCPI_CMD_SENSOR_CFG_BOUNDS,
 182};
 183
 184/* List all commands used by this driver, used as indexes */
 185enum scpi_drv_cmds {
 186	CMD_SCPI_CAPABILITIES = 0,
 187	CMD_GET_CLOCK_INFO,
 188	CMD_GET_CLOCK_VALUE,
 189	CMD_SET_CLOCK_VALUE,
 190	CMD_GET_DVFS,
 191	CMD_SET_DVFS,
 192	CMD_GET_DVFS_INFO,
 193	CMD_SENSOR_CAPABILITIES,
 194	CMD_SENSOR_INFO,
 195	CMD_SENSOR_VALUE,
 196	CMD_SET_DEVICE_PWR_STATE,
 197	CMD_GET_DEVICE_PWR_STATE,
 198	CMD_MAX_COUNT,
 199};
 200
 201static int scpi_std_commands[CMD_MAX_COUNT] = {
 202	SCPI_CMD_SCPI_CAPABILITIES,
 203	SCPI_CMD_GET_CLOCK_INFO,
 204	SCPI_CMD_GET_CLOCK_VALUE,
 205	SCPI_CMD_SET_CLOCK_VALUE,
 206	SCPI_CMD_GET_DVFS,
 207	SCPI_CMD_SET_DVFS,
 208	SCPI_CMD_GET_DVFS_INFO,
 209	SCPI_CMD_SENSOR_CAPABILITIES,
 210	SCPI_CMD_SENSOR_INFO,
 211	SCPI_CMD_SENSOR_VALUE,
 212	SCPI_CMD_SET_DEVICE_PWR_STATE,
 213	SCPI_CMD_GET_DEVICE_PWR_STATE,
 214};
 215
 216static int scpi_legacy_commands[CMD_MAX_COUNT] = {
 217	LEGACY_SCPI_CMD_SCPI_CAPABILITIES,
 218	-1, /* GET_CLOCK_INFO */
 219	LEGACY_SCPI_CMD_GET_CLOCK_VALUE,
 220	LEGACY_SCPI_CMD_SET_CLOCK_VALUE,
 221	LEGACY_SCPI_CMD_GET_DVFS,
 222	LEGACY_SCPI_CMD_SET_DVFS,
 223	LEGACY_SCPI_CMD_GET_DVFS_INFO,
 224	LEGACY_SCPI_CMD_SENSOR_CAPABILITIES,
 225	LEGACY_SCPI_CMD_SENSOR_INFO,
 226	LEGACY_SCPI_CMD_SENSOR_VALUE,
 227	-1, /* SET_DEVICE_PWR_STATE */
 228	-1, /* GET_DEVICE_PWR_STATE */
 229};
 230
 231struct scpi_xfer {
 232	u32 slot; /* has to be first element */
 233	u32 cmd;
 234	u32 status;
 235	const void *tx_buf;
 236	void *rx_buf;
 237	unsigned int tx_len;
 238	unsigned int rx_len;
 239	struct list_head node;
 240	struct completion done;
 241};
 242
 243struct scpi_chan {
 244	struct mbox_client cl;
 245	struct mbox_chan *chan;
 246	void __iomem *tx_payload;
 247	void __iomem *rx_payload;
 248	struct list_head rx_pending;
 249	struct list_head xfers_list;
 250	struct scpi_xfer *xfers;
 251	spinlock_t rx_lock; /* locking for the rx pending list */
 252	struct mutex xfers_lock;
 253	u8 token;
 254};
 255
 256struct scpi_drvinfo {
 257	u32 protocol_version;
 258	u32 firmware_version;
 259	bool is_legacy;
 260	int num_chans;
 261	int *commands;
 262	DECLARE_BITMAP(cmd_priority, LEGACY_SCPI_CMD_COUNT);
 263	atomic_t next_chan;
 264	struct scpi_ops *scpi_ops;
 265	struct scpi_chan *channels;
 266	struct scpi_dvfs_info *dvfs[MAX_DVFS_DOMAINS];
 267};
 268
 269/*
 270 * The SCP firmware only executes in little-endian mode, so any buffers
 271 * shared through SCPI should have their contents converted to little-endian
 272 */
 273struct scpi_shared_mem {
 274	__le32 command;
 275	__le32 status;
 276	u8 payload[0];
 277} __packed;
 278
 279struct legacy_scpi_shared_mem {
 280	__le32 status;
 281	u8 payload[0];
 282} __packed;
 283
 284struct scp_capabilities {
 285	__le32 protocol_version;
 286	__le32 event_version;
 287	__le32 platform_version;
 288	__le32 commands[4];
 289} __packed;
 290
 291struct clk_get_info {
 292	__le16 id;
 293	__le16 flags;
 294	__le32 min_rate;
 295	__le32 max_rate;
 296	u8 name[20];
 297} __packed;
 298
 299struct clk_set_value {
 300	__le16 id;
 301	__le16 reserved;
 302	__le32 rate;
 303} __packed;
 304
 305struct legacy_clk_set_value {
 306	__le32 rate;
 307	__le16 id;
 308	__le16 reserved;
 309} __packed;
 310
 311struct dvfs_info {
 312	u8 domain;
 313	u8 opp_count;
 314	__le16 latency;
 315	struct {
 316		__le32 freq;
 317		__le32 m_volt;
 318	} opps[MAX_DVFS_OPPS];
 319} __packed;
 320
 321struct dvfs_set {
 322	u8 domain;
 323	u8 index;
 324} __packed;
 325
 326struct _scpi_sensor_info {
 327	__le16 sensor_id;
 328	u8 class;
 329	u8 trigger_type;
 330	char name[20];
 331};
 332
 333struct dev_pstate_set {
 334	__le16 dev_id;
 335	u8 pstate;
 336} __packed;
 337
 338static struct scpi_drvinfo *scpi_info;
 339
 340static int scpi_linux_errmap[SCPI_ERR_MAX] = {
 341	/* better than switch case as long as return value is continuous */
 342	0, /* SCPI_SUCCESS */
 343	-EINVAL, /* SCPI_ERR_PARAM */
 344	-ENOEXEC, /* SCPI_ERR_ALIGN */
 345	-EMSGSIZE, /* SCPI_ERR_SIZE */
 346	-EINVAL, /* SCPI_ERR_HANDLER */
 347	-EACCES, /* SCPI_ERR_ACCESS */
 348	-ERANGE, /* SCPI_ERR_RANGE */
 349	-ETIMEDOUT, /* SCPI_ERR_TIMEOUT */
 350	-ENOMEM, /* SCPI_ERR_NOMEM */
 351	-EINVAL, /* SCPI_ERR_PWRSTATE */
 352	-EOPNOTSUPP, /* SCPI_ERR_SUPPORT */
 353	-EIO, /* SCPI_ERR_DEVICE */
 354	-EBUSY, /* SCPI_ERR_BUSY */
 355};
 356
 357static inline int scpi_to_linux_errno(int errno)
 358{
 359	if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX)
 360		return scpi_linux_errmap[errno];
 361	return -EIO;
 362}
 363
 364static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd)
 365{
 366	unsigned long flags;
 367	struct scpi_xfer *t, *match = NULL;
 368
 369	spin_lock_irqsave(&ch->rx_lock, flags);
 370	if (list_empty(&ch->rx_pending)) {
 371		spin_unlock_irqrestore(&ch->rx_lock, flags);
 372		return;
 373	}
 374
 375	/* Command type is not replied by the SCP Firmware in legacy Mode
 376	 * We should consider that command is the head of pending RX commands
 377	 * if the list is not empty. In TX only mode, the list would be empty.
 378	 */
 379	if (scpi_info->is_legacy) {
 380		match = list_first_entry(&ch->rx_pending, struct scpi_xfer,
 381					 node);
 382		list_del(&match->node);
 383	} else {
 384		list_for_each_entry(t, &ch->rx_pending, node)
 385			if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) {
 386				list_del(&t->node);
 387				match = t;
 388				break;
 389			}
 390	}
 391	/* check if wait_for_completion is in progress or timed-out */
 392	if (match && !completion_done(&match->done)) {
 393		unsigned int len;
 394
 395		if (scpi_info->is_legacy) {
 396			struct legacy_scpi_shared_mem __iomem *mem =
 397							ch->rx_payload;
 398
 399			/* RX Length is not replied by the legacy Firmware */
 400			len = match->rx_len;
 401
 402			match->status = ioread32(&mem->status);
 403			memcpy_fromio(match->rx_buf, mem->payload, len);
 404		} else {
 405			struct scpi_shared_mem __iomem *mem = ch->rx_payload;
 406
 407			len = min_t(unsigned int, match->rx_len, CMD_SIZE(cmd));
 408
 409			match->status = ioread32(&mem->status);
 410			memcpy_fromio(match->rx_buf, mem->payload, len);
 411		}
 412
 413		if (match->rx_len > len)
 414			memset(match->rx_buf + len, 0, match->rx_len - len);
 415		complete(&match->done);
 416	}
 417	spin_unlock_irqrestore(&ch->rx_lock, flags);
 418}
 419
 420static void scpi_handle_remote_msg(struct mbox_client *c, void *msg)
 421{
 422	struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
 423	struct scpi_shared_mem __iomem *mem = ch->rx_payload;
 424	u32 cmd = 0;
 425
 426	if (!scpi_info->is_legacy)
 427		cmd = ioread32(&mem->command);
 428
 429	scpi_process_cmd(ch, cmd);
 430}
 431
 432static void scpi_tx_prepare(struct mbox_client *c, void *msg)
 433{
 434	unsigned long flags;
 435	struct scpi_xfer *t = msg;
 436	struct scpi_chan *ch = container_of(c, struct scpi_chan, cl);
 437	struct scpi_shared_mem __iomem *mem = ch->tx_payload;
 438
 439	if (t->tx_buf) {
 440		if (scpi_info->is_legacy)
 441			memcpy_toio(ch->tx_payload, t->tx_buf, t->tx_len);
 442		else
 443			memcpy_toio(mem->payload, t->tx_buf, t->tx_len);
 444	}
 445
 446	if (t->rx_buf) {
 447		if (!(++ch->token))
 448			++ch->token;
 449		t->cmd |= FIELD_PREP(CMD_TOKEN_ID_MASK, ch->token);
 450		spin_lock_irqsave(&ch->rx_lock, flags);
 451		list_add_tail(&t->node, &ch->rx_pending);
 452		spin_unlock_irqrestore(&ch->rx_lock, flags);
 453	}
 454
 455	if (!scpi_info->is_legacy)
 456		iowrite32(t->cmd, &mem->command);
 457}
 458
 459static struct scpi_xfer *get_scpi_xfer(struct scpi_chan *ch)
 460{
 461	struct scpi_xfer *t;
 462
 463	mutex_lock(&ch->xfers_lock);
 464	if (list_empty(&ch->xfers_list)) {
 465		mutex_unlock(&ch->xfers_lock);
 466		return NULL;
 467	}
 468	t = list_first_entry(&ch->xfers_list, struct scpi_xfer, node);
 469	list_del(&t->node);
 470	mutex_unlock(&ch->xfers_lock);
 471	return t;
 472}
 473
 474static void put_scpi_xfer(struct scpi_xfer *t, struct scpi_chan *ch)
 475{
 476	mutex_lock(&ch->xfers_lock);
 477	list_add_tail(&t->node, &ch->xfers_list);
 478	mutex_unlock(&ch->xfers_lock);
 479}
 480
 481static int scpi_send_message(u8 idx, void *tx_buf, unsigned int tx_len,
 482			     void *rx_buf, unsigned int rx_len)
 483{
 484	int ret;
 485	u8 chan;
 486	u8 cmd;
 487	struct scpi_xfer *msg;
 488	struct scpi_chan *scpi_chan;
 489
 490	if (scpi_info->commands[idx] < 0)
 491		return -EOPNOTSUPP;
 492
 493	cmd = scpi_info->commands[idx];
 494
 495	if (scpi_info->is_legacy)
 496		chan = test_bit(cmd, scpi_info->cmd_priority) ? 1 : 0;
 497	else
 498		chan = atomic_inc_return(&scpi_info->next_chan) %
 499			scpi_info->num_chans;
 500	scpi_chan = scpi_info->channels + chan;
 501
 502	msg = get_scpi_xfer(scpi_chan);
 503	if (!msg)
 504		return -ENOMEM;
 505
 506	if (scpi_info->is_legacy) {
 507		msg->cmd = PACK_LEGACY_SCPI_CMD(cmd, tx_len);
 508		msg->slot = msg->cmd;
 509	} else {
 510		msg->slot = BIT(SCPI_SLOT);
 511		msg->cmd = PACK_SCPI_CMD(cmd, tx_len);
 512	}
 513	msg->tx_buf = tx_buf;
 514	msg->tx_len = tx_len;
 515	msg->rx_buf = rx_buf;
 516	msg->rx_len = rx_len;
 517	reinit_completion(&msg->done);
 518
 519	ret = mbox_send_message(scpi_chan->chan, msg);
 520	if (ret < 0 || !rx_buf)
 521		goto out;
 522
 523	if (!wait_for_completion_timeout(&msg->done, MAX_RX_TIMEOUT))
 524		ret = -ETIMEDOUT;
 525	else
 526		/* first status word */
 527		ret = msg->status;
 528out:
 529	if (ret < 0 && rx_buf) /* remove entry from the list if timed-out */
 530		scpi_process_cmd(scpi_chan, msg->cmd);
 531
 532	put_scpi_xfer(msg, scpi_chan);
 533	/* SCPI error codes > 0, translate them to Linux scale*/
 534	return ret > 0 ? scpi_to_linux_errno(ret) : ret;
 535}
 536
 537static u32 scpi_get_version(void)
 538{
 539	return scpi_info->protocol_version;
 540}
 541
 542static int
 543scpi_clk_get_range(u16 clk_id, unsigned long *min, unsigned long *max)
 544{
 545	int ret;
 546	struct clk_get_info clk;
 547	__le16 le_clk_id = cpu_to_le16(clk_id);
 548
 549	ret = scpi_send_message(CMD_GET_CLOCK_INFO, &le_clk_id,
 550				sizeof(le_clk_id), &clk, sizeof(clk));
 551	if (!ret) {
 552		*min = le32_to_cpu(clk.min_rate);
 553		*max = le32_to_cpu(clk.max_rate);
 554	}
 555	return ret;
 556}
 557
 558static unsigned long scpi_clk_get_val(u16 clk_id)
 559{
 560	int ret;
 561	__le32 rate;
 562	__le16 le_clk_id = cpu_to_le16(clk_id);
 563
 564	ret = scpi_send_message(CMD_GET_CLOCK_VALUE, &le_clk_id,
 565				sizeof(le_clk_id), &rate, sizeof(rate));
 
 
 566
 567	return ret ? ret : le32_to_cpu(rate);
 568}
 569
 570static int scpi_clk_set_val(u16 clk_id, unsigned long rate)
 571{
 572	int stat;
 573	struct clk_set_value clk = {
 574		.id = cpu_to_le16(clk_id),
 575		.rate = cpu_to_le32(rate)
 576	};
 577
 578	return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
 579				 &stat, sizeof(stat));
 580}
 581
 582static int legacy_scpi_clk_set_val(u16 clk_id, unsigned long rate)
 583{
 584	int stat;
 585	struct legacy_clk_set_value clk = {
 586		.id = cpu_to_le16(clk_id),
 587		.rate = cpu_to_le32(rate)
 588	};
 589
 590	return scpi_send_message(CMD_SET_CLOCK_VALUE, &clk, sizeof(clk),
 591				 &stat, sizeof(stat));
 592}
 593
 594static int scpi_dvfs_get_idx(u8 domain)
 595{
 596	int ret;
 597	u8 dvfs_idx;
 598
 599	ret = scpi_send_message(CMD_GET_DVFS, &domain, sizeof(domain),
 600				&dvfs_idx, sizeof(dvfs_idx));
 601
 602	return ret ? ret : dvfs_idx;
 603}
 604
 605static int scpi_dvfs_set_idx(u8 domain, u8 index)
 606{
 607	int stat;
 608	struct dvfs_set dvfs = {domain, index};
 609
 610	return scpi_send_message(CMD_SET_DVFS, &dvfs, sizeof(dvfs),
 611				 &stat, sizeof(stat));
 612}
 613
 614static int opp_cmp_func(const void *opp1, const void *opp2)
 615{
 616	const struct scpi_opp *t1 = opp1, *t2 = opp2;
 617
 618	return t1->freq - t2->freq;
 619}
 620
 621static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain)
 622{
 623	struct scpi_dvfs_info *info;
 624	struct scpi_opp *opp;
 625	struct dvfs_info buf;
 626	int ret, i;
 627
 628	if (domain >= MAX_DVFS_DOMAINS)
 629		return ERR_PTR(-EINVAL);
 630
 631	if (scpi_info->dvfs[domain])	/* data already populated */
 632		return scpi_info->dvfs[domain];
 633
 634	ret = scpi_send_message(CMD_GET_DVFS_INFO, &domain, sizeof(domain),
 635				&buf, sizeof(buf));
 636	if (ret)
 637		return ERR_PTR(ret);
 638
 639	info = kmalloc(sizeof(*info), GFP_KERNEL);
 640	if (!info)
 641		return ERR_PTR(-ENOMEM);
 642
 643	info->count = buf.opp_count;
 644	info->latency = le16_to_cpu(buf.latency) * 1000; /* uS to nS */
 645
 646	info->opps = kcalloc(info->count, sizeof(*opp), GFP_KERNEL);
 647	if (!info->opps) {
 648		kfree(info);
 649		return ERR_PTR(-ENOMEM);
 650	}
 651
 652	for (i = 0, opp = info->opps; i < info->count; i++, opp++) {
 653		opp->freq = le32_to_cpu(buf.opps[i].freq);
 654		opp->m_volt = le32_to_cpu(buf.opps[i].m_volt);
 655	}
 656
 657	sort(info->opps, info->count, sizeof(*opp), opp_cmp_func, NULL);
 658
 659	scpi_info->dvfs[domain] = info;
 660	return info;
 661}
 662
 663static int scpi_dev_domain_id(struct device *dev)
 664{
 665	struct of_phandle_args clkspec;
 666
 667	if (of_parse_phandle_with_args(dev->of_node, "clocks", "#clock-cells",
 668				       0, &clkspec))
 669		return -EINVAL;
 670
 671	return clkspec.args[0];
 672}
 673
 674static struct scpi_dvfs_info *scpi_dvfs_info(struct device *dev)
 675{
 676	int domain = scpi_dev_domain_id(dev);
 677
 678	if (domain < 0)
 679		return ERR_PTR(domain);
 680
 681	return scpi_dvfs_get_info(domain);
 682}
 683
 684static int scpi_dvfs_get_transition_latency(struct device *dev)
 685{
 686	struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
 687
 688	if (IS_ERR(info))
 689		return PTR_ERR(info);
 690
 691	return info->latency;
 692}
 693
 694static int scpi_dvfs_add_opps_to_device(struct device *dev)
 695{
 696	int idx, ret;
 697	struct scpi_opp *opp;
 698	struct scpi_dvfs_info *info = scpi_dvfs_info(dev);
 699
 700	if (IS_ERR(info))
 701		return PTR_ERR(info);
 702
 703	if (!info->opps)
 704		return -EIO;
 705
 706	for (opp = info->opps, idx = 0; idx < info->count; idx++, opp++) {
 707		ret = dev_pm_opp_add(dev, opp->freq, opp->m_volt * 1000);
 708		if (ret) {
 709			dev_warn(dev, "failed to add opp %uHz %umV\n",
 710				 opp->freq, opp->m_volt);
 711			while (idx-- > 0)
 712				dev_pm_opp_remove(dev, (--opp)->freq);
 713			return ret;
 714		}
 715	}
 716	return 0;
 717}
 718
 719static int scpi_sensor_get_capability(u16 *sensors)
 720{
 721	__le16 cap;
 722	int ret;
 723
 724	ret = scpi_send_message(CMD_SENSOR_CAPABILITIES, NULL, 0, &cap,
 725				sizeof(cap));
 726	if (!ret)
 727		*sensors = le16_to_cpu(cap);
 728
 729	return ret;
 730}
 731
 732static int scpi_sensor_get_info(u16 sensor_id, struct scpi_sensor_info *info)
 733{
 734	__le16 id = cpu_to_le16(sensor_id);
 735	struct _scpi_sensor_info _info;
 736	int ret;
 737
 738	ret = scpi_send_message(CMD_SENSOR_INFO, &id, sizeof(id),
 739				&_info, sizeof(_info));
 740	if (!ret) {
 741		memcpy(info, &_info, sizeof(*info));
 742		info->sensor_id = le16_to_cpu(_info.sensor_id);
 743	}
 744
 745	return ret;
 746}
 747
 748static int scpi_sensor_get_value(u16 sensor, u64 *val)
 749{
 750	__le16 id = cpu_to_le16(sensor);
 751	__le64 value;
 752	int ret;
 753
 754	ret = scpi_send_message(CMD_SENSOR_VALUE, &id, sizeof(id),
 755				&value, sizeof(value));
 756	if (ret)
 757		return ret;
 758
 759	if (scpi_info->is_legacy)
 760		/* only 32-bits supported, upper 32 bits can be junk */
 761		*val = le32_to_cpup((__le32 *)&value);
 762	else
 763		*val = le64_to_cpu(value);
 764
 765	return 0;
 766}
 767
 768static int scpi_device_get_power_state(u16 dev_id)
 769{
 770	int ret;
 771	u8 pstate;
 772	__le16 id = cpu_to_le16(dev_id);
 773
 774	ret = scpi_send_message(CMD_GET_DEVICE_PWR_STATE, &id,
 775				sizeof(id), &pstate, sizeof(pstate));
 776	return ret ? ret : pstate;
 777}
 778
 779static int scpi_device_set_power_state(u16 dev_id, u8 pstate)
 780{
 781	int stat;
 782	struct dev_pstate_set dev_set = {
 783		.dev_id = cpu_to_le16(dev_id),
 784		.pstate = pstate,
 785	};
 786
 787	return scpi_send_message(CMD_SET_DEVICE_PWR_STATE, &dev_set,
 788				 sizeof(dev_set), &stat, sizeof(stat));
 789}
 790
 791static struct scpi_ops scpi_ops = {
 792	.get_version = scpi_get_version,
 793	.clk_get_range = scpi_clk_get_range,
 794	.clk_get_val = scpi_clk_get_val,
 795	.clk_set_val = scpi_clk_set_val,
 796	.dvfs_get_idx = scpi_dvfs_get_idx,
 797	.dvfs_set_idx = scpi_dvfs_set_idx,
 798	.dvfs_get_info = scpi_dvfs_get_info,
 799	.device_domain_id = scpi_dev_domain_id,
 800	.get_transition_latency = scpi_dvfs_get_transition_latency,
 801	.add_opps_to_device = scpi_dvfs_add_opps_to_device,
 802	.sensor_get_capability = scpi_sensor_get_capability,
 803	.sensor_get_info = scpi_sensor_get_info,
 804	.sensor_get_value = scpi_sensor_get_value,
 805	.device_get_power_state = scpi_device_get_power_state,
 806	.device_set_power_state = scpi_device_set_power_state,
 807};
 808
 809struct scpi_ops *get_scpi_ops(void)
 810{
 811	return scpi_info ? scpi_info->scpi_ops : NULL;
 812}
 813EXPORT_SYMBOL_GPL(get_scpi_ops);
 814
 815static int scpi_init_versions(struct scpi_drvinfo *info)
 816{
 817	int ret;
 818	struct scp_capabilities caps;
 819
 820	ret = scpi_send_message(CMD_SCPI_CAPABILITIES, NULL, 0,
 821				&caps, sizeof(caps));
 822	if (!ret) {
 823		info->protocol_version = le32_to_cpu(caps.protocol_version);
 824		info->firmware_version = le32_to_cpu(caps.platform_version);
 825	}
 826	/* Ignore error if not implemented */
 827	if (scpi_info->is_legacy && ret == -EOPNOTSUPP)
 828		return 0;
 829
 830	return ret;
 831}
 832
 833static ssize_t protocol_version_show(struct device *dev,
 834				     struct device_attribute *attr, char *buf)
 835{
 836	struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
 837
 838	return sprintf(buf, "%lu.%lu\n",
 839		FIELD_GET(PROTO_REV_MAJOR_MASK, scpi_info->protocol_version),
 840		FIELD_GET(PROTO_REV_MINOR_MASK, scpi_info->protocol_version));
 841}
 842static DEVICE_ATTR_RO(protocol_version);
 843
 844static ssize_t firmware_version_show(struct device *dev,
 845				     struct device_attribute *attr, char *buf)
 846{
 847	struct scpi_drvinfo *scpi_info = dev_get_drvdata(dev);
 848
 849	return sprintf(buf, "%lu.%lu.%lu\n",
 850		FIELD_GET(FW_REV_MAJOR_MASK, scpi_info->firmware_version),
 851		FIELD_GET(FW_REV_MINOR_MASK, scpi_info->firmware_version),
 852		FIELD_GET(FW_REV_PATCH_MASK, scpi_info->firmware_version));
 853}
 854static DEVICE_ATTR_RO(firmware_version);
 855
 856static struct attribute *versions_attrs[] = {
 857	&dev_attr_firmware_version.attr,
 858	&dev_attr_protocol_version.attr,
 859	NULL,
 860};
 861ATTRIBUTE_GROUPS(versions);
 862
 863static void scpi_free_channels(void *data)
 864{
 865	struct scpi_drvinfo *info = data;
 866	int i;
 867
 868	for (i = 0; i < info->num_chans; i++)
 869		mbox_free_channel(info->channels[i].chan);
 870}
 871
 872static int scpi_remove(struct platform_device *pdev)
 873{
 874	int i;
 875	struct scpi_drvinfo *info = platform_get_drvdata(pdev);
 876
 877	scpi_info = NULL; /* stop exporting SCPI ops through get_scpi_ops */
 878
 879	for (i = 0; i < MAX_DVFS_DOMAINS && info->dvfs[i]; i++) {
 880		kfree(info->dvfs[i]->opps);
 881		kfree(info->dvfs[i]);
 882	}
 883
 884	return 0;
 885}
 886
 887#define MAX_SCPI_XFERS		10
 888static int scpi_alloc_xfer_list(struct device *dev, struct scpi_chan *ch)
 889{
 890	int i;
 891	struct scpi_xfer *xfers;
 892
 893	xfers = devm_kzalloc(dev, MAX_SCPI_XFERS * sizeof(*xfers), GFP_KERNEL);
 894	if (!xfers)
 895		return -ENOMEM;
 896
 897	ch->xfers = xfers;
 898	for (i = 0; i < MAX_SCPI_XFERS; i++, xfers++) {
 899		init_completion(&xfers->done);
 900		list_add_tail(&xfers->node, &ch->xfers_list);
 901	}
 902
 903	return 0;
 904}
 905
 906static const struct of_device_id legacy_scpi_of_match[] = {
 907	{.compatible = "arm,scpi-pre-1.0"},
 908	{},
 
 
 
 909};
 910
 911static int scpi_probe(struct platform_device *pdev)
 912{
 913	int count, idx, ret;
 914	struct resource res;
 915	struct device *dev = &pdev->dev;
 916	struct device_node *np = dev->of_node;
 
 917
 918	scpi_info = devm_kzalloc(dev, sizeof(*scpi_info), GFP_KERNEL);
 919	if (!scpi_info)
 920		return -ENOMEM;
 921
 922	if (of_match_device(legacy_scpi_of_match, &pdev->dev))
 923		scpi_info->is_legacy = true;
 924
 925	count = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");
 926	if (count < 0) {
 927		dev_err(dev, "no mboxes property in '%pOF'\n", np);
 928		return -ENODEV;
 929	}
 930
 931	scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
 932					   GFP_KERNEL);
 933	if (!scpi_info->channels)
 934		return -ENOMEM;
 935
 936	ret = devm_add_action(dev, scpi_free_channels, scpi_info);
 937	if (ret)
 938		return ret;
 939
 940	for (; scpi_info->num_chans < count; scpi_info->num_chans++) {
 941		resource_size_t size;
 942		int idx = scpi_info->num_chans;
 943		struct scpi_chan *pchan = scpi_info->channels + idx;
 944		struct mbox_client *cl = &pchan->cl;
 945		struct device_node *shmem = of_parse_phandle(np, "shmem", idx);
 946
 
 
 
 947		ret = of_address_to_resource(shmem, 0, &res);
 948		of_node_put(shmem);
 949		if (ret) {
 950			dev_err(dev, "failed to get SCPI payload mem resource\n");
 951			return ret;
 952		}
 953
 954		size = resource_size(&res);
 955		pchan->rx_payload = devm_ioremap(dev, res.start, size);
 956		if (!pchan->rx_payload) {
 957			dev_err(dev, "failed to ioremap SCPI payload\n");
 958			return -EADDRNOTAVAIL;
 959		}
 960		pchan->tx_payload = pchan->rx_payload + (size >> 1);
 961
 962		cl->dev = dev;
 963		cl->rx_callback = scpi_handle_remote_msg;
 964		cl->tx_prepare = scpi_tx_prepare;
 965		cl->tx_block = true;
 966		cl->tx_tout = 20;
 967		cl->knows_txdone = false; /* controller can't ack */
 968
 969		INIT_LIST_HEAD(&pchan->rx_pending);
 970		INIT_LIST_HEAD(&pchan->xfers_list);
 971		spin_lock_init(&pchan->rx_lock);
 972		mutex_init(&pchan->xfers_lock);
 973
 974		ret = scpi_alloc_xfer_list(dev, pchan);
 975		if (!ret) {
 976			pchan->chan = mbox_request_channel(cl, idx);
 977			if (!IS_ERR(pchan->chan))
 978				continue;
 979			ret = PTR_ERR(pchan->chan);
 980			if (ret != -EPROBE_DEFER)
 981				dev_err(dev, "failed to get channel%d err %d\n",
 982					idx, ret);
 983		}
 984		return ret;
 985	}
 986
 987	scpi_info->commands = scpi_std_commands;
 988
 989	platform_set_drvdata(pdev, scpi_info);
 990
 991	if (scpi_info->is_legacy) {
 992		/* Replace with legacy variants */
 993		scpi_ops.clk_set_val = legacy_scpi_clk_set_val;
 994		scpi_info->commands = scpi_legacy_commands;
 995
 996		/* Fill priority bitmap */
 997		for (idx = 0; idx < ARRAY_SIZE(legacy_hpriority_cmds); idx++)
 998			set_bit(legacy_hpriority_cmds[idx],
 999				scpi_info->cmd_priority);
1000	}
1001
1002	ret = scpi_init_versions(scpi_info);
 
 
1003	if (ret) {
1004		dev_err(dev, "incorrect or no SCP firmware found\n");
 
1005		return ret;
1006	}
1007
1008	if (scpi_info->is_legacy && !scpi_info->protocol_version &&
1009	    !scpi_info->firmware_version)
1010		dev_info(dev, "SCP Protocol legacy pre-1.0 firmware\n");
1011	else
1012		dev_info(dev, "SCP Protocol %lu.%lu Firmware %lu.%lu.%lu version\n",
1013			 FIELD_GET(PROTO_REV_MAJOR_MASK,
1014				   scpi_info->protocol_version),
1015			 FIELD_GET(PROTO_REV_MINOR_MASK,
1016				   scpi_info->protocol_version),
1017			 FIELD_GET(FW_REV_MAJOR_MASK,
1018				   scpi_info->firmware_version),
1019			 FIELD_GET(FW_REV_MINOR_MASK,
1020				   scpi_info->firmware_version),
1021			 FIELD_GET(FW_REV_PATCH_MASK,
1022				   scpi_info->firmware_version));
1023	scpi_info->scpi_ops = &scpi_ops;
 
1024
1025	ret = devm_device_add_groups(dev, versions_groups);
1026	if (ret)
1027		dev_err(dev, "unable to create sysfs version group\n");
1028
1029	return devm_of_platform_populate(dev);
1030}
1031
1032static const struct of_device_id scpi_of_match[] = {
1033	{.compatible = "arm,scpi"},
1034	{.compatible = "arm,scpi-pre-1.0"},
1035	{},
1036};
1037
1038MODULE_DEVICE_TABLE(of, scpi_of_match);
1039
1040static struct platform_driver scpi_driver = {
1041	.driver = {
1042		.name = "scpi_protocol",
1043		.of_match_table = scpi_of_match,
 
1044	},
1045	.probe = scpi_probe,
1046	.remove = scpi_remove,
1047};
1048module_platform_driver(scpi_driver);
1049
1050MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
1051MODULE_DESCRIPTION("ARM SCPI mailbox protocol driver");
1052MODULE_LICENSE("GPL v2");