summaryrefslogtreecommitdiffstats
path: root/drivers/net/wwan/t7xx/t7xx_state_monitor.c
blob: 80edb8e75a6ad7b0207e069ec96b34ebfa507699 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2021, MediaTek Inc.
 * Copyright (c) 2021-2022, Intel Corporation.
 *
 * Authors:
 *  Haijun Liu <haijun.liu@mediatek.com>
 *  Eliot Lee <eliot.lee@intel.com>
 *  Moises Veleta <moises.veleta@intel.com>
 *  Ricardo Martinez <ricardo.martinez@linux.intel.com>
 *
 * Contributors:
 *  Amir Hanania <amir.hanania@intel.com>
 *  Sreehari Kancharla <sreehari.kancharla@intel.com>
 */

#include <linux/bits.h>
#include <linux/bitfield.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gfp.h>
#include <linux/iopoll.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/wait.h>

#include "t7xx_hif_cldma.h"
#include "t7xx_mhccif.h"
#include "t7xx_modem_ops.h"
#include "t7xx_pci.h"
#include "t7xx_pcie_mac.h"
#include "t7xx_port_proxy.h"
#include "t7xx_reg.h"
#include "t7xx_state_monitor.h"

#define FSM_DRM_DISABLE_DELAY_MS		200
#define FSM_EVENT_POLL_INTERVAL_MS		20
#define FSM_MD_EX_REC_OK_TIMEOUT_MS		10000
#define FSM_MD_EX_PASS_TIMEOUT_MS		45000
#define FSM_CMD_TIMEOUT_MS			2000

void t7xx_fsm_notifier_register(struct t7xx_modem *md, struct t7xx_fsm_notifier *notifier)
{
	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
	unsigned long flags;

	spin_lock_irqsave(&ctl->notifier_lock, flags);
	list_add_tail(&notifier->entry, &ctl->notifier_list);
	spin_unlock_irqrestore(&ctl->notifier_lock, flags);
}

void t7xx_fsm_notifier_unregister(struct t7xx_modem *md, struct t7xx_fsm_notifier *notifier)
{
	struct t7xx_fsm_notifier *notifier_cur, *notifier_next;
	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
	unsigned long flags;

	spin_lock_irqsave(&ctl->notifier_lock, flags);
	list_for_each_entry_safe(notifier_cur, notifier_next, &ctl->notifier_list, entry) {
		if (notifier_cur == notifier)
			list_del(&notifier->entry);
	}
	spin_unlock_irqrestore(&ctl->notifier_lock, flags);
}

static void fsm_state_notify(struct t7xx_modem *md, enum md_state state)
{
	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;
	struct t7xx_fsm_notifier *notifier;
	unsigned long flags;

	spin_lock_irqsave(&ctl->notifier_lock, flags);
	list_for_each_entry(notifier, &ctl->notifier_list, entry) {
		spin_unlock_irqrestore(&ctl->notifier_lock, flags);
		if (notifier->notifier_fn)
			notifier->notifier_fn(state, notifier->data);

		spin_lock_irqsave(&ctl->notifier_lock, flags);
	}
	spin_unlock_irqrestore(&ctl->notifier_lock, flags);
}

void t7xx_fsm_broadcast_state(struct t7xx_fsm_ctl *ctl, enum md_state state)
{
	ctl->md_state = state;

	/* Update to port first, otherwise sending message on HS2 may fail */
	t7xx_port_proxy_md_status_notify(ctl->md->port_prox, state);
	fsm_state_notify(ctl->md, state);
}

static void fsm_finish_command(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd, int result)
{
	if (cmd->flag & FSM_CMD_FLAG_WAIT_FOR_COMPLETION) {
		*cmd->ret = result;
		complete_all(cmd->done);
	}

	kfree(cmd);
}

static void fsm_del_kf_event(struct t7xx_fsm_event *event)
{
	list_del(&event->entry);
	kfree(event);
}

static void fsm_flush_event_cmd_qs(struct t7xx_fsm_ctl *ctl)
{
	struct device *dev = &ctl->md->t7xx_dev->pdev->dev;
	struct t7xx_fsm_event *event, *evt_next;
	struct t7xx_fsm_command *cmd, *cmd_next;
	unsigned long flags;

	spin_lock_irqsave(&ctl->command_lock, flags);
	list_for_each_entry_safe(cmd, cmd_next, &ctl->command_queue, entry) {
		dev_warn(dev, "Unhandled command %d\n", cmd->cmd_id);
		list_del(&cmd->entry);
		fsm_finish_command(ctl, cmd, -EINVAL);
	}
	spin_unlock_irqrestore(&ctl->command_lock, flags);

	spin_lock_irqsave(&ctl->event_lock, flags);
	list_for_each_entry_safe(event, evt_next, &ctl->event_queue, entry) {
		dev_warn(dev, "Unhandled event %d\n", event->event_id);
		fsm_del_kf_event(event);
	}
	spin_unlock_irqrestore(&ctl->event_lock, flags);
}

static void fsm_wait_for_event(struct t7xx_fsm_ctl *ctl, enum t7xx_fsm_event_state event_expected,
			       enum t7xx_fsm_event_state event_ignore, int retries)
{
	struct t7xx_fsm_event *event;
	bool event_received = false;
	unsigned long flags;
	int cnt = 0;

	while (cnt++ < retries && !event_received) {
		bool sleep_required = true;

		if (kthread_should_stop())
			return;

		spin_lock_irqsave(&ctl->event_lock, flags);
		event = list_first_entry_or_null(&ctl->event_queue, struct t7xx_fsm_event, entry);
		if (event) {
			event_received = event->event_id == event_expected;
			if (event_received || event->event_id == event_ignore) {
				fsm_del_kf_event(event);
				sleep_required = false;
			}
		}
		spin_unlock_irqrestore(&ctl->event_lock, flags);

		if (sleep_required)
			msleep(FSM_EVENT_POLL_INTERVAL_MS);
	}
}

static void fsm_routine_exception(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd,
				  enum t7xx_ex_reason reason)
{
	struct device *dev = &ctl->md->t7xx_dev->pdev->dev;

	if (ctl->curr_state != FSM_STATE_READY && ctl->curr_state != FSM_STATE_STARTING) {
		if (cmd)
			fsm_finish_command(ctl, cmd, -EINVAL);

		return;
	}

	ctl->curr_state = FSM_STATE_EXCEPTION;

	switch (reason) {
	case EXCEPTION_HS_TIMEOUT:
		dev_err(dev, "Boot Handshake failure\n");
		break;

	case EXCEPTION_EVENT:
		dev_err(dev, "Exception event\n");
		t7xx_fsm_broadcast_state(ctl, MD_STATE_EXCEPTION);
		t7xx_pci_pm_exp_detected(ctl->md->t7xx_dev);
		t7xx_md_exception_handshake(ctl->md);

		fsm_wait_for_event(ctl, FSM_EVENT_MD_EX_REC_OK, FSM_EVENT_MD_EX,
				   FSM_MD_EX_REC_OK_TIMEOUT_MS / FSM_EVENT_POLL_INTERVAL_MS);
		fsm_wait_for_event(ctl, FSM_EVENT_MD_EX_PASS, FSM_EVENT_INVALID,
				   FSM_MD_EX_PASS_TIMEOUT_MS / FSM_EVENT_POLL_INTERVAL_MS);
		break;

	default:
		dev_err(dev, "Exception %d\n", reason);
		break;
	}

	if (cmd)
		fsm_finish_command(ctl, cmd, 0);
}

static int fsm_stopped_handler(struct t7xx_fsm_ctl *ctl)
{
	ctl->curr_state = FSM_STATE_STOPPED;

	t7xx_fsm_broadcast_state(ctl, MD_STATE_STOPPED);
	return t7xx_md_reset(ctl->md->t7xx_dev);
}

static void fsm_routine_stopped(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd)
{
	if (ctl->curr_state == FSM_STATE_STOPPED) {
		fsm_finish_command(ctl, cmd, -EINVAL);
		return;
	}

	fsm_finish_command(ctl, cmd, fsm_stopped_handler(ctl));
}

static void fsm_routine_stopping(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd)
{
	struct t7xx_pci_dev *t7xx_dev;
	struct cldma_ctrl *md_ctrl;
	int err;

	if (ctl->curr_state == FSM_STATE_STOPPED || ctl->curr_state == FSM_STATE_STOPPING) {
		fsm_finish_command(ctl, cmd, -EINVAL);
		return;
	}

	md_ctrl = ctl->md->md_ctrl[CLDMA_ID_MD];
	t7xx_dev = ctl->md->t7xx_dev;

	ctl->curr_state = FSM_STATE_STOPPING;
	t7xx_fsm_broadcast_state(ctl, MD_STATE_WAITING_TO_STOP);
	t7xx_cldma_stop(md_ctrl);

	if (!ctl->md->rgu_irq_asserted) {
		t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_DRM_DISABLE_AP);
		/* Wait for the DRM disable to take effect */
		msleep(FSM_DRM_DISABLE_DELAY_MS);

		err = t7xx_acpi_fldr_func(t7xx_dev);
		if (err)
			t7xx_mhccif_h2d_swint_trigger(t7xx_dev, H2D_CH_DEVICE_RESET);
	}

	fsm_finish_command(ctl, cmd, fsm_stopped_handler(ctl));
}

static void t7xx_fsm_broadcast_ready_state(struct t7xx_fsm_ctl *ctl)
{
	if (ctl->md_state != MD_STATE_WAITING_FOR_HS2)
		return;

	ctl->md_state = MD_STATE_READY;

	fsm_state_notify(ctl->md, MD_STATE_READY);
	t7xx_port_proxy_md_status_notify(ctl->md->port_prox, MD_STATE_READY);
}

static void fsm_routine_ready(struct t7xx_fsm_ctl *ctl)
{
	struct t7xx_modem *md = ctl->md;

	ctl->curr_state = FSM_STATE_READY;
	t7xx_fsm_broadcast_ready_state(ctl);
	t7xx_md_event_notify(md, FSM_READY);
}

static int fsm_routine_starting(struct t7xx_fsm_ctl *ctl)
{
	struct t7xx_modem *md = ctl->md;
	struct device *dev;

	ctl->curr_state = FSM_STATE_STARTING;

	t7xx_fsm_broadcast_state(ctl, MD_STATE_WAITING_FOR_HS1);
	t7xx_md_event_notify(md, FSM_START);

	wait_event_interruptible_timeout(ctl->async_hk_wq,
					 (md->core_md.ready && md->core_ap.ready) ||
					  ctl->exp_flg, HZ * 60);
	dev = &md->t7xx_dev->pdev->dev;

	if (ctl->exp_flg)
		dev_err(dev, "MD exception is captured during handshake\n");

	if (!md->core_md.ready) {
		dev_err(dev, "MD handshake timeout\n");
		if (md->core_md.handshake_ongoing)
			t7xx_fsm_append_event(ctl, FSM_EVENT_MD_HS2_EXIT, NULL, 0);

		fsm_routine_exception(ctl, NULL, EXCEPTION_HS_TIMEOUT);
		return -ETIMEDOUT;
	} else if (!md->core_ap.ready) {
		dev_err(dev, "AP handshake timeout\n");
		if (md->core_ap.handshake_ongoing)
			t7xx_fsm_append_event(ctl, FSM_EVENT_AP_HS2_EXIT, NULL, 0);

		fsm_routine_exception(ctl, NULL, EXCEPTION_HS_TIMEOUT);
		return -ETIMEDOUT;
	}

	t7xx_pci_pm_init_late(md->t7xx_dev);
	fsm_routine_ready(ctl);
	return 0;
}

static void fsm_routine_start(struct t7xx_fsm_ctl *ctl, struct t7xx_fsm_command *cmd)
{
	struct t7xx_modem *md = ctl->md;
	u32 dev_status;
	int ret;

	if (!md)
		return;

	if (ctl->curr_state != FSM_STATE_INIT && ctl->curr_state != FSM_STATE_PRE_START &&
	    ctl->curr_state != FSM_STATE_STOPPED) {
		fsm_finish_command(ctl, cmd, -EINVAL);
		return;
	}

	ctl->curr_state = FSM_STATE_PRE_START;
	t7xx_md_event_notify(md, FSM_PRE_START);

	ret = read_poll_timeout(ioread32, dev_status,
				(dev_status & MISC_STAGE_MASK) == LINUX_STAGE, 20000, 2000000,
				false, IREG_BASE(md->t7xx_dev) + T7XX_PCIE_MISC_DEV_STATUS);
	if (ret) {
		struct device *dev = &md->t7xx_dev->pdev->dev;

		fsm_finish_command(ctl, cmd, -ETIMEDOUT);
		dev_err(dev, "Invalid device status 0x%lx\n", dev_status & MISC_STAGE_MASK);
		return;
	}

	t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_AP]);
	t7xx_cldma_hif_hw_init(md->md_ctrl[CLDMA_ID_MD]);
	fsm_finish_command(ctl, cmd, fsm_routine_starting(ctl));
}

static int fsm_main_thread(void *data)
{
	struct t7xx_fsm_ctl *ctl = data;
	struct t7xx_fsm_command *cmd;
	unsigned long flags;

	while (!kthread_should_stop()) {
		if (wait_event_interruptible(ctl->command_wq, !list_empty(&ctl->command_queue) ||
					     kthread_should_stop()))
			continue;

		if (kthread_should_stop())
			break;

		spin_lock_irqsave(&ctl->command_lock, flags);
		cmd = list_first_entry(&ctl->command_queue, struct t7xx_fsm_command, entry);
		list_del(&cmd->entry);
		spin_unlock_irqrestore(&ctl->command_lock, flags);

		switch (cmd->cmd_id) {
		case FSM_CMD_START:
			fsm_routine_start(ctl, cmd);
			break;

		case FSM_CMD_EXCEPTION:
			fsm_routine_exception(ctl, cmd, FIELD_GET(FSM_CMD_EX_REASON, cmd->flag));
			break;

		case FSM_CMD_PRE_STOP:
			fsm_routine_stopping(ctl, cmd);
			break;

		case FSM_CMD_STOP:
			fsm_routine_stopped(ctl, cmd);
			break;

		default:
			fsm_finish_command(ctl, cmd, -EINVAL);
			fsm_flush_event_cmd_qs(ctl);
			break;
		}
	}

	return 0;
}

int t7xx_fsm_append_cmd(struct t7xx_fsm_ctl *ctl, enum t7xx_fsm_cmd_state cmd_id, unsigned int flag)
{
	DECLARE_COMPLETION_ONSTACK(done);
	struct t7xx_fsm_command *cmd;
	unsigned long flags;
	int ret;

	cmd = kzalloc(sizeof(*cmd), flag & FSM_CMD_FLAG_IN_INTERRUPT ? GFP_ATOMIC : GFP_KERNEL);
	if (!cmd)
		return -ENOMEM;

	INIT_LIST_HEAD(&cmd->entry);
	cmd->cmd_id = cmd_id;
	cmd->flag = flag;
	if (flag & FSM_CMD_FLAG_WAIT_FOR_COMPLETION) {
		cmd->done = &done;
		cmd->ret = &ret;
	}

	spin_lock_irqsave(&ctl->command_lock, flags);
	list_add_tail(&cmd->entry, &ctl->command_queue);
	spin_unlock_irqrestore(&ctl->command_lock, flags);

	wake_up(&ctl->command_wq);

	if (flag & FSM_CMD_FLAG_WAIT_FOR_COMPLETION) {
		unsigned long wait_ret;

		wait_ret = wait_for_completion_timeout(&done,
						       msecs_to_jiffies(FSM_CMD_TIMEOUT_MS));
		if (!wait_ret)
			return -ETIMEDOUT;

		return ret;
	}

	return 0;
}

int t7xx_fsm_append_event(struct t7xx_fsm_ctl *ctl, enum t7xx_fsm_event_state event_id,
			  unsigned char *data, unsigned int length)
{
	struct device *dev = &ctl->md->t7xx_dev->pdev->dev;
	struct t7xx_fsm_event *event;
	unsigned long flags;

	if (event_id <= FSM_EVENT_INVALID || event_id >= FSM_EVENT_MAX) {
		dev_err(dev, "Invalid event %d\n", event_id);
		return -EINVAL;
	}

	event = kmalloc(sizeof(*event) + length, in_interrupt() ? GFP_ATOMIC : GFP_KERNEL);
	if (!event)
		return -ENOMEM;

	INIT_LIST_HEAD(&event->entry);
	event->event_id = event_id;
	event->length = length;

	if (data && length)
		memcpy(event->data, data, length);

	spin_lock_irqsave(&ctl->event_lock, flags);
	list_add_tail(&event->entry, &ctl->event_queue);
	spin_unlock_irqrestore(&ctl->event_lock, flags);

	wake_up_all(&ctl->event_wq);
	return 0;
}

void t7xx_fsm_clr_event(struct t7xx_fsm_ctl *ctl, enum t7xx_fsm_event_state event_id)
{
	struct t7xx_fsm_event *event, *evt_next;
	unsigned long flags;

	spin_lock_irqsave(&ctl->event_lock, flags);
	list_for_each_entry_safe(event, evt_next, &ctl->event_queue, entry) {
		if (event->event_id == event_id)
			fsm_del_kf_event(event);
	}
	spin_unlock_irqrestore(&ctl->event_lock, flags);
}

enum md_state t7xx_fsm_get_md_state(struct t7xx_fsm_ctl *ctl)
{
	if (ctl)
		return ctl->md_state;

	return MD_STATE_INVALID;
}

unsigned int t7xx_fsm_get_ctl_state(struct t7xx_fsm_ctl *ctl)
{
	if (ctl)
		return ctl->curr_state;

	return FSM_STATE_STOPPED;
}

int t7xx_fsm_recv_md_intr(struct t7xx_fsm_ctl *ctl, enum t7xx_md_irq_type type)
{
	unsigned int cmd_flags = FSM_CMD_FLAG_IN_INTERRUPT;

	if (type == MD_IRQ_PORT_ENUM) {
		return t7xx_fsm_append_cmd(ctl, FSM_CMD_START, cmd_flags);
	} else if (type == MD_IRQ_CCIF_EX) {
		ctl->exp_flg = true;
		wake_up(&ctl->async_hk_wq);
		cmd_flags |= FIELD_PREP(FSM_CMD_EX_REASON, EXCEPTION_EVENT);
		return t7xx_fsm_append_cmd(ctl, FSM_CMD_EXCEPTION, cmd_flags);
	}

	return -EINVAL;
}

void t7xx_fsm_reset(struct t7xx_modem *md)
{
	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;

	fsm_flush_event_cmd_qs(ctl);
	ctl->curr_state = FSM_STATE_STOPPED;
	ctl->exp_flg = false;
}

int t7xx_fsm_init(struct t7xx_modem *md)
{
	struct device *dev = &md->t7xx_dev->pdev->dev;
	struct t7xx_fsm_ctl *ctl;

	ctl = devm_kzalloc(dev, sizeof(*ctl), GFP_KERNEL);
	if (!ctl)
		return -ENOMEM;

	md->fsm_ctl = ctl;
	ctl->md = md;
	ctl->curr_state = FSM_STATE_INIT;
	INIT_LIST_HEAD(&ctl->command_queue);
	INIT_LIST_HEAD(&ctl->event_queue);
	init_waitqueue_head(&ctl->async_hk_wq);
	init_waitqueue_head(&ctl->event_wq);
	INIT_LIST_HEAD(&ctl->notifier_list);
	init_waitqueue_head(&ctl->command_wq);
	spin_lock_init(&ctl->event_lock);
	spin_lock_init(&ctl->command_lock);
	ctl->exp_flg = false;
	spin_lock_init(&ctl->notifier_lock);

	ctl->fsm_thread = kthread_run(fsm_main_thread, ctl, "t7xx_fsm");
	return PTR_ERR_OR_ZERO(ctl->fsm_thread);
}

void t7xx_fsm_uninit(struct t7xx_modem *md)
{
	struct t7xx_fsm_ctl *ctl = md->fsm_ctl;

	if (!ctl)
		return;

	if (ctl->fsm_thread)
		kthread_stop(ctl->fsm_thread);

	fsm_flush_event_cmd_qs(ctl);
}