1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AMx3 Wkup M3 IPC driver
4 *
5 * Copyright (C) 2015 Texas Instruments, Inc.
6 *
7 * Dave Gerlach <d-gerlach@ti.com>
8 */
9
10#include <linux/debugfs.h>
11#include <linux/err.h>
12#include <linux/firmware.h>
13#include <linux/kernel.h>
14#include <linux/kthread.h>
15#include <linux/interrupt.h>
16#include <linux/irq.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/omap-mailbox.h>
20#include <linux/platform_device.h>
21#include <linux/remoteproc.h>
22#include <linux/suspend.h>
23#include <linux/wkup_m3_ipc.h>
24
25#define AM33XX_CTRL_IPC_REG_COUNT	0x8
26#define AM33XX_CTRL_IPC_REG_OFFSET(m)	(0x4 + 4 * (m))
27
28/* AM33XX M3_TXEV_EOI register */
29#define AM33XX_CONTROL_M3_TXEV_EOI	0x00
30
31#define AM33XX_M3_TXEV_ACK		(0x1 << 0)
32#define AM33XX_M3_TXEV_ENABLE		(0x0 << 0)
33
34#define IPC_CMD_DS0			0x4
35#define IPC_CMD_STANDBY			0xc
36#define IPC_CMD_IDLE			0x10
37#define IPC_CMD_RESET			0xe
38#define DS_IPC_DEFAULT			0xffffffff
39#define M3_VERSION_UNKNOWN		0x0000ffff
40#define M3_BASELINE_VERSION		0x191
41#define M3_STATUS_RESP_MASK		(0xffff << 16)
42#define M3_FW_VERSION_MASK		0xffff
43#define M3_WAKE_SRC_MASK		0xff
44
45#define IPC_MEM_TYPE_SHIFT		(0x0)
46#define IPC_MEM_TYPE_MASK		(0x7 << 0)
47#define IPC_VTT_STAT_SHIFT		(0x3)
48#define IPC_VTT_STAT_MASK		(0x1 << 3)
49#define IPC_VTT_GPIO_PIN_SHIFT		(0x4)
50#define IPC_VTT_GPIO_PIN_MASK		(0x3f << 4)
51#define IPC_IO_ISOLATION_STAT_SHIFT	(10)
52#define IPC_IO_ISOLATION_STAT_MASK	(0x1 << 10)
53
54#define IPC_DBG_HALT_SHIFT		(11)
55#define IPC_DBG_HALT_MASK		(0x1 << 11)
56
57#define M3_STATE_UNKNOWN		0
58#define M3_STATE_RESET			1
59#define M3_STATE_INITED			2
60#define M3_STATE_MSG_FOR_LP		3
61#define M3_STATE_MSG_FOR_RESET		4
62
63#define WKUP_M3_SD_FW_MAGIC		0x570C
64
65#define WKUP_M3_DMEM_START		0x80000
66#define WKUP_M3_AUXDATA_OFFSET		0x1000
67#define WKUP_M3_AUXDATA_SIZE		0xFF
68
69static struct wkup_m3_ipc *m3_ipc_state;
70
71static const struct wkup_m3_wakeup_src wakeups[] = {
72	{.irq_nr = 16,	.src = "PRCM"},
73	{.irq_nr = 35,	.src = "USB0_PHY"},
74	{.irq_nr = 36,	.src = "USB1_PHY"},
75	{.irq_nr = 40,	.src = "I2C0"},
76	{.irq_nr = 41,	.src = "RTC Timer"},
77	{.irq_nr = 42,	.src = "RTC Alarm"},
78	{.irq_nr = 43,	.src = "Timer0"},
79	{.irq_nr = 44,	.src = "Timer1"},
80	{.irq_nr = 45,	.src = "UART"},
81	{.irq_nr = 46,	.src = "GPIO0"},
82	{.irq_nr = 48,	.src = "MPU_WAKE"},
83	{.irq_nr = 49,	.src = "WDT0"},
84	{.irq_nr = 50,	.src = "WDT1"},
85	{.irq_nr = 51,	.src = "ADC_TSC"},
86	{.irq_nr = 0,	.src = "Unknown"},
87};
88
89/**
90 * wkup_m3_copy_aux_data - Copy auxiliary data to special region of m3 dmem
91 * @data - pointer to data
92 * @sz - size of data to copy (limit 256 bytes)
93 *
94 * Copies any additional blob of data to the wkup_m3 dmem to be used by the
95 * firmware
96 */
97static unsigned long wkup_m3_copy_aux_data(struct wkup_m3_ipc *m3_ipc,
98					   const void *data, int sz)
99{
100	unsigned long aux_data_dev_addr;
101	void *aux_data_addr;
102
103	aux_data_dev_addr = WKUP_M3_DMEM_START + WKUP_M3_AUXDATA_OFFSET;
104	aux_data_addr = rproc_da_to_va(m3_ipc->rproc,
105				       aux_data_dev_addr,
106				       WKUP_M3_AUXDATA_SIZE,
107				       NULL);
108	memcpy(aux_data_addr, data, sz);
109
110	return WKUP_M3_AUXDATA_OFFSET;
111}
112
113static void wkup_m3_scale_data_fw_cb(const struct firmware *fw, void *context)
114{
115	unsigned long val, aux_base;
116	struct wkup_m3_scale_data_header hdr;
117	struct wkup_m3_ipc *m3_ipc = context;
118	struct device *dev = m3_ipc->dev;
119
120	if (!fw) {
121		dev_err(dev, "Voltage scale fw name given but file missing.\n");
122		return;
123	}
124
125	memcpy(&hdr, fw->data, sizeof(hdr));
126
127	if (hdr.magic != WKUP_M3_SD_FW_MAGIC) {
128		dev_err(dev, "PM: Voltage Scale Data binary does not appear valid.\n");
129		goto release_sd_fw;
130	}
131
132	aux_base = wkup_m3_copy_aux_data(m3_ipc, fw->data + sizeof(hdr),
133					 fw->size - sizeof(hdr));
134
135	val = (aux_base + hdr.sleep_offset);
136	val |= ((aux_base + hdr.wake_offset) << 16);
137
138	m3_ipc->volt_scale_offsets = val;
139
140release_sd_fw:
141	release_firmware(fw);
142};
143
144static int wkup_m3_init_scale_data(struct wkup_m3_ipc *m3_ipc,
145				   struct device *dev)
146{
147	int ret = 0;
148
149	/*
150	 * If no name is provided, user has already been warned, pm will
151	 * still work so return 0
152	 */
153
154	if (!m3_ipc->sd_fw_name)
155		return ret;
156
157	ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT,
158				      m3_ipc->sd_fw_name, dev, GFP_ATOMIC,
159				      m3_ipc, wkup_m3_scale_data_fw_cb);
160
161	return ret;
162}
163
164#ifdef CONFIG_DEBUG_FS
165static void wkup_m3_set_halt_late(bool enabled)
166{
167	if (enabled)
168		m3_ipc_state->halt = (1 << IPC_DBG_HALT_SHIFT);
169	else
170		m3_ipc_state->halt = 0;
171}
172
173static int option_get(void *data, u64 *val)
174{
175	u32 *option = data;
176
177	*val = *option;
178
179	return 0;
180}
181
182static int option_set(void *data, u64 val)
183{
184	u32 *option = data;
185
186	*option = val;
187
188	if (option == &m3_ipc_state->halt) {
189		if (val)
190			wkup_m3_set_halt_late(true);
191		else
192			wkup_m3_set_halt_late(false);
193	}
194
195	return 0;
196}
197
198DEFINE_SIMPLE_ATTRIBUTE(wkup_m3_ipc_option_fops, option_get, option_set,
199			"%llu\n");
200
201static int wkup_m3_ipc_dbg_init(struct wkup_m3_ipc *m3_ipc)
202{
203	m3_ipc->dbg_path = debugfs_create_dir("wkup_m3_ipc", NULL);
204
205	if (IS_ERR(m3_ipc->dbg_path))
206		return -EINVAL;
207
208	(void)debugfs_create_file("enable_late_halt", 0644,
209				  m3_ipc->dbg_path,
210				  &m3_ipc->halt,
211				  &wkup_m3_ipc_option_fops);
212
213	return 0;
214}
215
216static inline void wkup_m3_ipc_dbg_destroy(struct wkup_m3_ipc *m3_ipc)
217{
218	debugfs_remove_recursive(m3_ipc->dbg_path);
219}
220#else
221static inline int wkup_m3_ipc_dbg_init(struct wkup_m3_ipc *m3_ipc)
222{
223	return 0;
224}
225
226static inline void wkup_m3_ipc_dbg_destroy(struct wkup_m3_ipc *m3_ipc)
227{
228}
229#endif /* CONFIG_DEBUG_FS */
230
231static void am33xx_txev_eoi(struct wkup_m3_ipc *m3_ipc)
232{
233	writel(AM33XX_M3_TXEV_ACK,
234	       m3_ipc->ipc_mem_base + AM33XX_CONTROL_M3_TXEV_EOI);
235}
236
237static void am33xx_txev_enable(struct wkup_m3_ipc *m3_ipc)
238{
239	writel(AM33XX_M3_TXEV_ENABLE,
240	       m3_ipc->ipc_mem_base + AM33XX_CONTROL_M3_TXEV_EOI);
241}
242
243static void wkup_m3_ctrl_ipc_write(struct wkup_m3_ipc *m3_ipc,
244				   u32 val, int ipc_reg_num)
245{
246	if (WARN(ipc_reg_num < 0 || ipc_reg_num > AM33XX_CTRL_IPC_REG_COUNT,
247		 "ipc register operation out of range"))
248		return;
249
250	writel(val, m3_ipc->ipc_mem_base +
251	       AM33XX_CTRL_IPC_REG_OFFSET(ipc_reg_num));
252}
253
254static unsigned int wkup_m3_ctrl_ipc_read(struct wkup_m3_ipc *m3_ipc,
255					  int ipc_reg_num)
256{
257	if (WARN(ipc_reg_num < 0 || ipc_reg_num > AM33XX_CTRL_IPC_REG_COUNT,
258		 "ipc register operation out of range"))
259		return 0;
260
261	return readl(m3_ipc->ipc_mem_base +
262		     AM33XX_CTRL_IPC_REG_OFFSET(ipc_reg_num));
263}
264
265static int wkup_m3_fw_version_read(struct wkup_m3_ipc *m3_ipc)
266{
267	int val;
268
269	val = wkup_m3_ctrl_ipc_read(m3_ipc, 2);
270
271	return val & M3_FW_VERSION_MASK;
272}
273
274static irqreturn_t wkup_m3_txev_handler(int irq, void *ipc_data)
275{
276	struct wkup_m3_ipc *m3_ipc = ipc_data;
277	struct device *dev = m3_ipc->dev;
278	int ver = 0;
279
280	am33xx_txev_eoi(m3_ipc);
281
282	switch (m3_ipc->state) {
283	case M3_STATE_RESET:
284		ver = wkup_m3_fw_version_read(m3_ipc);
285
286		if (ver == M3_VERSION_UNKNOWN ||
287		    ver < M3_BASELINE_VERSION) {
288			dev_warn(dev, "CM3 Firmware Version %x not supported\n",
289				 ver);
290		} else {
291			dev_info(dev, "CM3 Firmware Version = 0x%x\n", ver);
292		}
293
294		m3_ipc->state = M3_STATE_INITED;
295		wkup_m3_init_scale_data(m3_ipc, dev);
296		complete(&m3_ipc->sync_complete);
297		break;
298	case M3_STATE_MSG_FOR_RESET:
299		m3_ipc->state = M3_STATE_INITED;
300		complete(&m3_ipc->sync_complete);
301		break;
302	case M3_STATE_MSG_FOR_LP:
303		complete(&m3_ipc->sync_complete);
304		break;
305	case M3_STATE_UNKNOWN:
306		dev_warn(dev, "Unknown CM3 State\n");
307	}
308
309	am33xx_txev_enable(m3_ipc);
310
311	return IRQ_HANDLED;
312}
313
314static int wkup_m3_ping(struct wkup_m3_ipc *m3_ipc)
315{
316	struct device *dev = m3_ipc->dev;
317	mbox_msg_t dummy_msg = 0;
318	int ret;
319
320	if (!m3_ipc->mbox) {
321		dev_err(dev,
322			"No IPC channel to communicate with wkup_m3!\n");
323		return -EIO;
324	}
325
326	/*
327	 * Write a dummy message to the mailbox in order to trigger the RX
328	 * interrupt to alert the M3 that data is available in the IPC
329	 * registers. We must enable the IRQ here and disable it after in
330	 * the RX callback to avoid multiple interrupts being received
331	 * by the CM3.
332	 */
333	ret = mbox_send_message(m3_ipc->mbox, &dummy_msg);
334	if (ret < 0) {
335		dev_err(dev, "%s: mbox_send_message() failed: %d\n",
336			__func__, ret);
337		return ret;
338	}
339
340	ret = wait_for_completion_timeout(&m3_ipc->sync_complete,
341					  msecs_to_jiffies(500));
342	if (!ret) {
343		dev_err(dev, "MPU<->CM3 sync failure\n");
344		m3_ipc->state = M3_STATE_UNKNOWN;
345		return -EIO;
346	}
347
348	mbox_client_txdone(m3_ipc->mbox, 0);
349	return 0;
350}
351
352static int wkup_m3_ping_noirq(struct wkup_m3_ipc *m3_ipc)
353{
354	struct device *dev = m3_ipc->dev;
355	mbox_msg_t dummy_msg = 0;
356	int ret;
357
358	if (!m3_ipc->mbox) {
359		dev_err(dev,
360			"No IPC channel to communicate with wkup_m3!\n");
361		return -EIO;
362	}
363
364	ret = mbox_send_message(m3_ipc->mbox, &dummy_msg);
365	if (ret < 0) {
366		dev_err(dev, "%s: mbox_send_message() failed: %d\n",
367			__func__, ret);
368		return ret;
369	}
370
371	mbox_client_txdone(m3_ipc->mbox, 0);
372	return 0;
373}
374
375static int wkup_m3_is_available(struct wkup_m3_ipc *m3_ipc)
376{
377	return ((m3_ipc->state != M3_STATE_RESET) &&
378		(m3_ipc->state != M3_STATE_UNKNOWN));
379}
380
381static void wkup_m3_set_vtt_gpio(struct wkup_m3_ipc *m3_ipc, int gpio)
382{
383	m3_ipc->vtt_conf = (1 << IPC_VTT_STAT_SHIFT) |
384			    (gpio << IPC_VTT_GPIO_PIN_SHIFT);
385}
386
387static void wkup_m3_set_io_isolation(struct wkup_m3_ipc *m3_ipc)
388{
389	m3_ipc->isolation_conf = (1 << IPC_IO_ISOLATION_STAT_SHIFT);
390}
391
392/* Public functions */
393/**
394 * wkup_m3_set_mem_type - Pass wkup_m3 which type of memory is in use
395 * @m3_ipc: Pointer to wkup_m3_ipc context
396 * @mem_type: memory type value read directly from emif
397 *
398 * wkup_m3 must know what memory type is in use to properly suspend
399 * and resume.
400 */
401static void wkup_m3_set_mem_type(struct wkup_m3_ipc *m3_ipc, int mem_type)
402{
403	m3_ipc->mem_type = mem_type;
404}
405
406/**
407 * wkup_m3_set_resume_address - Pass wkup_m3 resume address
408 * @m3_ipc: Pointer to wkup_m3_ipc context
409 * @addr: Physical address from which resume code should execute
410 */
411static void wkup_m3_set_resume_address(struct wkup_m3_ipc *m3_ipc, void *addr)
412{
413	m3_ipc->resume_addr = (unsigned long)addr;
414}
415
416/**
417 * wkup_m3_request_pm_status - Retrieve wkup_m3 status code after suspend
418 * @m3_ipc: Pointer to wkup_m3_ipc context
419 *
420 * Returns code representing the status of a low power mode transition.
421 *	0 - Successful transition
422 *	1 - Failure to transition to low power state
423 */
424static int wkup_m3_request_pm_status(struct wkup_m3_ipc *m3_ipc)
425{
426	unsigned int i;
427	int val;
428
429	val = wkup_m3_ctrl_ipc_read(m3_ipc, 1);
430
431	i = M3_STATUS_RESP_MASK & val;
432	i >>= __ffs(M3_STATUS_RESP_MASK);
433
434	return i;
435}
436
437/**
438 * wkup_m3_prepare_low_power - Request preparation for transition to
439 *			       low power state
440 * @m3_ipc: Pointer to wkup_m3_ipc context
441 * @state: A kernel suspend state to enter, either MEM or STANDBY
442 *
443 * Returns 0 if preparation was successful, otherwise returns error code
444 */
445static int wkup_m3_prepare_low_power(struct wkup_m3_ipc *m3_ipc, int state)
446{
447	struct device *dev = m3_ipc->dev;
448	int m3_power_state;
449	int ret = 0;
450
451	if (!wkup_m3_is_available(m3_ipc))
452		return -ENODEV;
453
454	switch (state) {
455	case WKUP_M3_DEEPSLEEP:
456		m3_power_state = IPC_CMD_DS0;
457		wkup_m3_ctrl_ipc_write(m3_ipc, m3_ipc->volt_scale_offsets, 5);
458		break;
459	case WKUP_M3_STANDBY:
460		m3_power_state = IPC_CMD_STANDBY;
461		wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 5);
462		break;
463	case WKUP_M3_IDLE:
464		m3_power_state = IPC_CMD_IDLE;
465		wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 5);
466		break;
467	default:
468		return 1;
469	}
470
471	/* Program each required IPC register then write defaults to others */
472	wkup_m3_ctrl_ipc_write(m3_ipc, m3_ipc->resume_addr, 0);
473	wkup_m3_ctrl_ipc_write(m3_ipc, m3_power_state, 1);
474	wkup_m3_ctrl_ipc_write(m3_ipc, m3_ipc->mem_type |
475			       m3_ipc->vtt_conf |
476			       m3_ipc->isolation_conf |
477			       m3_ipc->halt, 4);
478
479	wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 2);
480	wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 3);
481	wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 6);
482	wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 7);
483
484	m3_ipc->state = M3_STATE_MSG_FOR_LP;
485
486	if (state == WKUP_M3_IDLE)
487		ret = wkup_m3_ping_noirq(m3_ipc);
488	else
489		ret = wkup_m3_ping(m3_ipc);
490
491	if (ret) {
492		dev_err(dev, "Unable to ping CM3\n");
493		return ret;
494	}
495
496	return 0;
497}
498
499/**
500 * wkup_m3_finish_low_power - Return m3 to reset state
501 * @m3_ipc: Pointer to wkup_m3_ipc context
502 *
503 * Returns 0 if reset was successful, otherwise returns error code
504 */
505static int wkup_m3_finish_low_power(struct wkup_m3_ipc *m3_ipc)
506{
507	struct device *dev = m3_ipc->dev;
508	int ret = 0;
509
510	if (!wkup_m3_is_available(m3_ipc))
511		return -ENODEV;
512
513	wkup_m3_ctrl_ipc_write(m3_ipc, IPC_CMD_RESET, 1);
514	wkup_m3_ctrl_ipc_write(m3_ipc, DS_IPC_DEFAULT, 2);
515
516	m3_ipc->state = M3_STATE_MSG_FOR_RESET;
517
518	ret = wkup_m3_ping(m3_ipc);
519	if (ret) {
520		dev_err(dev, "Unable to ping CM3\n");
521		return ret;
522	}
523
524	return 0;
525}
526
527/**
528 * wkup_m3_request_wake_src - Get the wakeup source info passed from wkup_m3
529 * @m3_ipc: Pointer to wkup_m3_ipc context
530 */
531static const char *wkup_m3_request_wake_src(struct wkup_m3_ipc *m3_ipc)
532{
533	unsigned int wakeup_src_idx;
534	int j, val;
535
536	val = wkup_m3_ctrl_ipc_read(m3_ipc, 6);
537
538	wakeup_src_idx = val & M3_WAKE_SRC_MASK;
539
540	for (j = 0; j < ARRAY_SIZE(wakeups) - 1; j++) {
541		if (wakeups[j].irq_nr == wakeup_src_idx)
542			return wakeups[j].src;
543	}
544	return wakeups[j].src;
545}
546
547/**
548 * wkup_m3_set_rtc_only - Set the rtc_only flag
549 * @m3_ipc: Pointer to wkup_m3_ipc context
550 */
551static void wkup_m3_set_rtc_only(struct wkup_m3_ipc *m3_ipc)
552{
553	if (m3_ipc_state)
554		m3_ipc_state->is_rtc_only = true;
555}
556
557static struct wkup_m3_ipc_ops ipc_ops = {
558	.set_mem_type = wkup_m3_set_mem_type,
559	.set_resume_address = wkup_m3_set_resume_address,
560	.prepare_low_power = wkup_m3_prepare_low_power,
561	.finish_low_power = wkup_m3_finish_low_power,
562	.request_pm_status = wkup_m3_request_pm_status,
563	.request_wake_src = wkup_m3_request_wake_src,
564	.set_rtc_only = wkup_m3_set_rtc_only,
565};
566
567/**
568 * wkup_m3_ipc_get - Return handle to wkup_m3_ipc
569 *
570 * Returns NULL if the wkup_m3 is not yet available, otherwise returns
571 * pointer to wkup_m3_ipc struct.
572 */
573struct wkup_m3_ipc *wkup_m3_ipc_get(void)
574{
575	if (m3_ipc_state)
576		get_device(m3_ipc_state->dev);
577	else
578		return NULL;
579
580	return m3_ipc_state;
581}
582EXPORT_SYMBOL_GPL(wkup_m3_ipc_get);
583
584/**
585 * wkup_m3_ipc_put - Free handle to wkup_m3_ipc returned from wkup_m3_ipc_get
586 * @m3_ipc: A pointer to wkup_m3_ipc struct returned by wkup_m3_ipc_get
587 */
588void wkup_m3_ipc_put(struct wkup_m3_ipc *m3_ipc)
589{
590	if (m3_ipc_state)
591		put_device(m3_ipc_state->dev);
592}
593EXPORT_SYMBOL_GPL(wkup_m3_ipc_put);
594
595static int wkup_m3_rproc_boot_thread(void *arg)
596{
597	struct wkup_m3_ipc *m3_ipc = arg;
598	struct device *dev = m3_ipc->dev;
599	int ret;
600
601	init_completion(&m3_ipc->sync_complete);
602
603	ret = rproc_boot(m3_ipc->rproc);
604	if (ret)
605		dev_err(dev, "rproc_boot failed\n");
606	else
607		m3_ipc_state = m3_ipc;
608
609	return 0;
610}
611
612static int wkup_m3_ipc_probe(struct platform_device *pdev)
613{
614	struct device *dev = &pdev->dev;
615	int irq, ret, temp;
616	phandle rproc_phandle;
617	struct rproc *m3_rproc;
618	struct task_struct *task;
619	struct wkup_m3_ipc *m3_ipc;
620	struct device_node *np = dev->of_node;
621
622	m3_ipc = devm_kzalloc(dev, sizeof(*m3_ipc), GFP_KERNEL);
623	if (!m3_ipc)
624		return -ENOMEM;
625
626	m3_ipc->ipc_mem_base = devm_platform_ioremap_resource(pdev, 0);
627	if (IS_ERR(m3_ipc->ipc_mem_base))
628		return PTR_ERR(m3_ipc->ipc_mem_base);
629
630	irq = platform_get_irq(pdev, 0);
631	if (irq < 0)
632		return irq;
633
634	ret = devm_request_irq(dev, irq, wkup_m3_txev_handler,
635			       0, "wkup_m3_txev", m3_ipc);
636	if (ret) {
637		dev_err(dev, "request_irq failed\n");
638		return ret;
639	}
640
641	m3_ipc->mbox_client.dev = dev;
642	m3_ipc->mbox_client.tx_done = NULL;
643	m3_ipc->mbox_client.tx_prepare = NULL;
644	m3_ipc->mbox_client.rx_callback = NULL;
645	m3_ipc->mbox_client.tx_block = false;
646	m3_ipc->mbox_client.knows_txdone = false;
647
648	m3_ipc->mbox = mbox_request_channel(&m3_ipc->mbox_client, 0);
649
650	if (IS_ERR(m3_ipc->mbox)) {
651		dev_err(dev, "IPC Request for A8->M3 Channel failed! %ld\n",
652			PTR_ERR(m3_ipc->mbox));
653		return PTR_ERR(m3_ipc->mbox);
654	}
655
656	if (of_property_read_u32(dev->of_node, "ti,rproc", &rproc_phandle)) {
657		dev_err(&pdev->dev, "could not get rproc phandle\n");
658		ret = -ENODEV;
659		goto err_free_mbox;
660	}
661
662	m3_rproc = rproc_get_by_phandle(rproc_phandle);
663	if (!m3_rproc) {
664		dev_err(&pdev->dev, "could not get rproc handle\n");
665		ret = -EPROBE_DEFER;
666		goto err_free_mbox;
667	}
668
669	m3_ipc->rproc = m3_rproc;
670	m3_ipc->dev = dev;
671	m3_ipc->state = M3_STATE_RESET;
672
673	m3_ipc->ops = &ipc_ops;
674
675	if (!of_property_read_u32(np, "ti,vtt-gpio-pin", &temp)) {
676		if (temp >= 0 && temp <= 31)
677			wkup_m3_set_vtt_gpio(m3_ipc, temp);
678		else
679			dev_warn(dev, "Invalid VTT GPIO(%d) pin\n", temp);
680	}
681
682	if (of_property_read_bool(np, "ti,set-io-isolation"))
683		wkup_m3_set_io_isolation(m3_ipc);
684
685	ret = of_property_read_string(np, "firmware-name",
686				      &m3_ipc->sd_fw_name);
687	if (ret) {
688		dev_dbg(dev, "Voltage scaling data blob not provided from DT.\n");
689	}
690
691	/*
692	 * Wait for firmware loading completion in a thread so we
693	 * can boot the wkup_m3 as soon as it's ready without holding
694	 * up kernel boot
695	 */
696	task = kthread_run(wkup_m3_rproc_boot_thread, m3_ipc,
697			   "wkup_m3_rproc_loader");
698
699	if (IS_ERR(task)) {
700		dev_err(dev, "can't create rproc_boot thread\n");
701		ret = PTR_ERR(task);
702		goto err_put_rproc;
703	}
704
705	wkup_m3_ipc_dbg_init(m3_ipc);
706
707	return 0;
708
709err_put_rproc:
710	rproc_put(m3_rproc);
711err_free_mbox:
712	mbox_free_channel(m3_ipc->mbox);
713	return ret;
714}
715
716static int wkup_m3_ipc_remove(struct platform_device *pdev)
717{
718	wkup_m3_ipc_dbg_destroy(m3_ipc_state);
719
720	mbox_free_channel(m3_ipc_state->mbox);
721
722	rproc_shutdown(m3_ipc_state->rproc);
723	rproc_put(m3_ipc_state->rproc);
724
725	m3_ipc_state = NULL;
726
727	return 0;
728}
729
730static int __maybe_unused wkup_m3_ipc_suspend(struct device *dev)
731{
732	/*
733	 * Nothing needs to be done on suspend even with rtc_only flag set
734	 */
735	return 0;
736}
737
738static int __maybe_unused wkup_m3_ipc_resume(struct device *dev)
739{
740	if (m3_ipc_state->is_rtc_only) {
741		rproc_shutdown(m3_ipc_state->rproc);
742		rproc_boot(m3_ipc_state->rproc);
743	}
744
745	m3_ipc_state->is_rtc_only = false;
746
747	return 0;
748}
749
750static const struct dev_pm_ops wkup_m3_ipc_pm_ops = {
751	SET_SYSTEM_SLEEP_PM_OPS(wkup_m3_ipc_suspend, wkup_m3_ipc_resume)
752};
753
754static const struct of_device_id wkup_m3_ipc_of_match[] = {
755	{ .compatible = "ti,am3352-wkup-m3-ipc", },
756	{ .compatible = "ti,am4372-wkup-m3-ipc", },
757	{},
758};
759MODULE_DEVICE_TABLE(of, wkup_m3_ipc_of_match);
760
761static struct platform_driver wkup_m3_ipc_driver = {
762	.probe = wkup_m3_ipc_probe,
763	.remove = wkup_m3_ipc_remove,
764	.driver = {
765		.name = "wkup_m3_ipc",
766		.of_match_table = wkup_m3_ipc_of_match,
767		.pm = &wkup_m3_ipc_pm_ops,
768	},
769};
770
771module_platform_driver(wkup_m3_ipc_driver);
772
773MODULE_LICENSE("GPL v2");
774MODULE_DESCRIPTION("wkup m3 remote processor ipc driver");
775MODULE_AUTHOR("Dave Gerlach <d-gerlach@ti.com>");
776