summaryrefslogtreecommitdiffstats
path: root/driver/hdm-dim2/dim2_hdm.c
blob: 35aee9fbbf02e0a1693dd7ffccdb32ff484206ce (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
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
/*
 * dim2_hdm.c - MediaLB DIM2 Hardware Dependent Module
 *
 * Copyright (C) 2015-2016, Microchip Technology Germany II GmbH & Co. KG
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * This file is licensed under GPLv2.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/printk.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/dma-mapping.h>
#include <linux/sched.h>
#include <linux/kthread.h>

#include <mostcore.h>
#include <networking.h>
#include "dim2_hal.h"
#include "dim2_hdm.h"
#include "dim2_errors.h"
#include "dim2_sysfs.h"

#define DMA_CHANNELS (32 - 1)  /* channel 0 is a system channel */

#define MAX_BUFFERS_PACKET      32
#define MAX_BUFFERS_STREAMING   32
#define MAX_BUF_SIZE_PACKET     2048
#define MAX_BUF_SIZE_STREAMING  (8 * 1024)

/* command line parameter to select clock speed */
static char *clock_speed;
module_param(clock_speed, charp, 0);
MODULE_PARM_DESC(clock_speed, "MediaLB Clock Speed");

/*
 * The parameter representing the number of frames per sub-buffer for
 * synchronous channels.  Valid values: [0 .. 6].
 *
 * The values 0, 1, 2, 3, 4, 5, 6 represent corresponding number of frames per
 * sub-buffer 1, 2, 4, 8, 16, 32, 64.
 */
static u8 fcnt = 4;  /* (1 << fcnt) frames per subbuffer */
module_param(fcnt, byte, 0);
MODULE_PARM_DESC(fcnt, "Num of frames per sub-buffer for sync channels as a power of 2");

static DEFINE_SPINLOCK(dim_lock);

static void dim2_tasklet_fn(unsigned long data);
static DECLARE_TASKLET(dim2_tasklet, dim2_tasklet_fn, 0);

/**
 * struct hdm_channel - private structure to keep channel specific data
 * @is_initialized: identifier to know whether the channel is initialized
 * @ch: HAL specific channel data
 * @pending_list: list to keep MBO's before starting transfer
 * @started_list: list to keep MBO's after starting transfer
 * @direction: channel direction (TX or RX)
 * @data_type: channel data type
 */
struct hdm_channel {
	char name[sizeof "caNNN"];
	bool is_initialized;
	struct dim_channel ch;
	struct list_head pending_list;	/* before dim_enqueue_buffer() */
	struct list_head started_list;	/* after dim_enqueue_buffer() */
	enum most_channel_direction direction;
	enum most_channel_data_type data_type;
};

/**
 * struct dim2_hdm - private structure to keep interface specific data
 * @hch: an array of channel specific data
 * @most_iface: most interface structure
 * @capabilities: an array of channel capability data
 * @io_base: I/O register base address
 * @clk_speed: user selectable (through command line parameter) clock speed
 * @netinfo_task: thread to deliver network status
 * @netinfo_waitq: waitq for the thread to sleep
 * @deliver_netinfo: to identify whether network status received
 * @mac_addrs: INIC mac address
 * @link_state: network link state
 * @atx_idx: index of async tx channel
 */
struct dim2_hdm {
	struct hdm_channel hch[DMA_CHANNELS];
	struct most_channel_capability capabilities[DMA_CHANNELS];
	struct most_interface most_iface;
	char name[16 + sizeof "dim2-"];
	void __iomem *io_base;
	int clk_speed;
	struct task_struct *netinfo_task;
	wait_queue_head_t netinfo_waitq;
	int deliver_netinfo;
	unsigned char mac_addrs[6];
	unsigned char link_state;
	int atx_idx;
	struct medialb_bus bus;
};

#define iface_to_hdm(iface) container_of(iface, struct dim2_hdm, most_iface)

/* Macro to identify a network status message */
#define PACKET_IS_NET_INFO(p)  \
	(((p)[1] == 0x18) && ((p)[2] == 0x05) && ((p)[3] == 0x0C) && \
	 ((p)[13] == 0x3C) && ((p)[14] == 0x00) && ((p)[15] == 0x0A))

bool dim2_sysfs_get_state_cb(void)
{
	bool state;
	unsigned long flags;

	spin_lock_irqsave(&dim_lock, flags);
	state = dim_get_lock_state();
	spin_unlock_irqrestore(&dim_lock, flags);

	return state;
}

/**
 * dimcb_io_read - callback from HAL to read an I/O register
 * @ptr32: register address
 */
u32 dimcb_io_read(u32 __iomem *ptr32)
{
	return readl(ptr32);
}

/**
 * dimcb_io_write - callback from HAL to write value to an I/O register
 * @ptr32: register address
 * @value: value to write
 */
void dimcb_io_write(u32 __iomem *ptr32, u32 value)
{
	writel(value, ptr32);
}

/**
 * dimcb_on_error - callback from HAL to report miscommunication between
 * HDM and HAL
 * @error_id: Error ID
 * @error_message: Error message. Some text in a free format
 */
void dimcb_on_error(u8 error_id, const char *error_message)
{
	pr_err("dimcb_on_error: error_id - %d, error_message - %s\n", error_id,
	       error_message);
}

/**
 * startup_dim - initialize the dim2 interface
 * @pdev: platform device
 *
 * Get the value of command line parameter "clock_speed" if given or use the
 * default value, enable the clock and PLL, and initialize the dim2 interface.
 */
static int startup_dim(struct platform_device *pdev)
{
	struct dim2_hdm *dev = platform_get_drvdata(pdev);
	struct dim2_platform_data *pdata = pdev->dev.platform_data;
	u8 hal_ret;

	dev->clk_speed = -1;

	if (clock_speed) {
		if (!strcmp(clock_speed, "256fs"))
			dev->clk_speed = CLK_256FS;
		else if (!strcmp(clock_speed, "512fs"))
			dev->clk_speed = CLK_512FS;
		else if (!strcmp(clock_speed, "1024fs"))
			dev->clk_speed = CLK_1024FS;
		else if (!strcmp(clock_speed, "2048fs"))
			dev->clk_speed = CLK_2048FS;
		else if (!strcmp(clock_speed, "3072fs"))
			dev->clk_speed = CLK_3072FS;
		else if (!strcmp(clock_speed, "4096fs"))
			dev->clk_speed = CLK_4096FS;
		else if (!strcmp(clock_speed, "6144fs"))
			dev->clk_speed = CLK_6144FS;
		else if (!strcmp(clock_speed, "8192fs"))
			dev->clk_speed = CLK_8192FS;
	}

	if (dev->clk_speed == -1) {
		pr_info("Bad or missing clock speed parameter, using default value: 3072fs\n");
		dev->clk_speed = CLK_3072FS;
	} else {
		pr_info("Selected clock speed: %s\n", clock_speed);
	}
	if (pdata && pdata->init) {
		int ret = pdata->init(pdata, dev->io_base, dev->clk_speed);

		if (ret)
			return ret;
	}

	pr_info("sync: num of frames per sub-buffer: %u\n", fcnt);
	hal_ret = dim_startup(dev->io_base, dev->clk_speed, fcnt);
	if (hal_ret != DIM_NO_ERROR) {
		pr_err("dim_startup failed: %d\n", hal_ret);
		if (pdata && pdata->destroy)
			pdata->destroy(pdata);
		return -ENODEV;
	}

	return 0;
}

/**
 * try_start_dim_transfer - try to transfer a buffer on a channel
 * @hdm_ch: channel specific data
 *
 * Transfer a buffer from pending_list if the channel is ready
 */
static int try_start_dim_transfer(struct hdm_channel *hdm_ch)
{
	u16 buf_size;
	struct list_head *head = &hdm_ch->pending_list;
	struct mbo *mbo;
	unsigned long flags;
	struct dim_ch_state_t st;

	BUG_ON(!hdm_ch);
	BUG_ON(!hdm_ch->is_initialized);

	spin_lock_irqsave(&dim_lock, flags);
	if (list_empty(head)) {
		spin_unlock_irqrestore(&dim_lock, flags);
		return -EAGAIN;
	}

	if (!dim_get_channel_state(&hdm_ch->ch, &st)->ready) {
		spin_unlock_irqrestore(&dim_lock, flags);
		return -EAGAIN;
	}

	mbo = list_first_entry(head, struct mbo, list);
	buf_size = mbo->buffer_length;

	if (dim_dbr_space(&hdm_ch->ch) < buf_size) {
		spin_unlock_irqrestore(&dim_lock, flags);
		return -EAGAIN;
	}

	BUG_ON(mbo->bus_address == 0);
	if (!dim_enqueue_buffer(&hdm_ch->ch, mbo->bus_address, buf_size)) {
		list_del(head->next);
		spin_unlock_irqrestore(&dim_lock, flags);
		mbo->processed_length = 0;
		mbo->status = MBO_E_INVAL;
		mbo->complete(mbo);
		return -EFAULT;
	}

	list_move_tail(head->next, &hdm_ch->started_list);
	spin_unlock_irqrestore(&dim_lock, flags);

	return 0;
}

/**
 * deliver_netinfo_thread - thread to deliver network status to mostcore
 * @data: private data
 *
 * Wait for network status and deliver it to mostcore once it is received
 */
static int deliver_netinfo_thread(void *data)
{
	struct dim2_hdm *dev = data;

	while (!kthread_should_stop()) {
		wait_event_interruptible(dev->netinfo_waitq,
					 dev->deliver_netinfo ||
					 kthread_should_stop());

		if (dev->deliver_netinfo) {
			dev->deliver_netinfo--;
			most_deliver_netinfo(&dev->most_iface, dev->link_state,
					     dev->mac_addrs);
		}
	}

	return 0;
}

/**
 * retrieve_netinfo - retrieve network status from received buffer
 * @dev: private data
 * @mbo: received MBO
 *
 * Parse the message in buffer and get node address, link state, MAC address.
 * Wake up a thread to deliver this status to mostcore
 */
static void retrieve_netinfo(struct dim2_hdm *dev, struct mbo *mbo)
{
	u8 *data = mbo->virt_address;

	pr_info("Node Address: 0x%03x\n", (u16)data[16] << 8 | data[17]);
	dev->link_state = data[18];
	pr_info("NIState: %d\n", dev->link_state);
	memcpy(dev->mac_addrs, data + 19, 6);
	dev->deliver_netinfo++;
	wake_up_interruptible(&dev->netinfo_waitq);
}

/**
 * service_done_flag - handle completed buffers
 * @dev: private data
 * @ch_idx: channel index
 *
 * Return back the completed buffers to mostcore, using completion callback
 */
static void service_done_flag(struct dim2_hdm *dev, int ch_idx)
{
	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
	struct dim_ch_state_t st;
	struct list_head *head;
	struct mbo *mbo;
	int done_buffers;
	unsigned long flags;
	u8 *data;

	BUG_ON(!hdm_ch);
	BUG_ON(!hdm_ch->is_initialized);

	spin_lock_irqsave(&dim_lock, flags);

	done_buffers = dim_get_channel_state(&hdm_ch->ch, &st)->done_buffers;
	if (!done_buffers) {
		spin_unlock_irqrestore(&dim_lock, flags);
		return;
	}

	if (!dim_detach_buffers(&hdm_ch->ch, done_buffers)) {
		spin_unlock_irqrestore(&dim_lock, flags);
		return;
	}
	spin_unlock_irqrestore(&dim_lock, flags);

	head = &hdm_ch->started_list;

	while (done_buffers) {
		spin_lock_irqsave(&dim_lock, flags);
		if (list_empty(head)) {
			spin_unlock_irqrestore(&dim_lock, flags);
			pr_crit("hard error: started_mbo list is empty whereas DIM2 has sent buffers\n");
			break;
		}

		mbo = list_first_entry(head, struct mbo, list);
		list_del(head->next);
		spin_unlock_irqrestore(&dim_lock, flags);

		data = mbo->virt_address;

		if (hdm_ch->data_type == MOST_CH_ASYNC &&
		    hdm_ch->direction == MOST_CH_RX &&
		    PACKET_IS_NET_INFO(data)) {
			retrieve_netinfo(dev, mbo);

			spin_lock_irqsave(&dim_lock, flags);
			list_add_tail(&mbo->list, &hdm_ch->pending_list);
			spin_unlock_irqrestore(&dim_lock, flags);
		} else {
			if (hdm_ch->data_type == MOST_CH_CONTROL ||
			    hdm_ch->data_type == MOST_CH_ASYNC) {
				u32 const data_size =
					(u32)data[0] * 256 + data[1] + 2;

				mbo->processed_length =
					min_t(u32, data_size,
					      mbo->buffer_length);
			} else {
				mbo->processed_length = mbo->buffer_length;
			}
			mbo->status = MBO_SUCCESS;
			mbo->complete(mbo);
		}

		done_buffers--;
	}
}

static struct dim_channel **get_active_channels(struct dim2_hdm *dev,
						struct dim_channel **buffer)
{
	int idx = 0;
	int ch_idx;

	for (ch_idx = 0; ch_idx < DMA_CHANNELS; ch_idx++) {
		if (dev->hch[ch_idx].is_initialized)
			buffer[idx++] = &dev->hch[ch_idx].ch;
	}
	buffer[idx++] = NULL;

	return buffer;
}

static irqreturn_t dim2_mlb_isr(int irq, void *_dev)
{
	struct dim2_hdm *dev = _dev;
	unsigned long flags;

	spin_lock_irqsave(&dim_lock, flags);
	dim_service_mlb_int_irq();
	spin_unlock_irqrestore(&dim_lock, flags);

	if (dev->atx_idx >= 0 && dev->hch[dev->atx_idx].is_initialized)
		while (!try_start_dim_transfer(dev->hch + dev->atx_idx))
			continue;

	return IRQ_HANDLED;
}

/**
 * dim2_tasklet_fn - tasklet function
 * @data: private data
 *
 * Service each initialized channel, if needed
 */
static void dim2_tasklet_fn(unsigned long data)
{
	struct dim2_hdm *dev = (struct dim2_hdm *)data;
	unsigned long flags;
	int ch_idx;

	for (ch_idx = 0; ch_idx < DMA_CHANNELS; ch_idx++) {
		if (!dev->hch[ch_idx].is_initialized)
			continue;

		spin_lock_irqsave(&dim_lock, flags);
		dim_service_channel(&dev->hch[ch_idx].ch);
		spin_unlock_irqrestore(&dim_lock, flags);

		service_done_flag(dev, ch_idx);
		while (!try_start_dim_transfer(dev->hch + ch_idx))
			continue;
	}
}

/**
 * dim2_ahb_isr - interrupt service routine
 * @irq: irq number
 * @_dev: private data
 *
 * Acknowledge the interrupt and schedule a tasklet to service channels.
 * Return IRQ_HANDLED.
 */
static irqreturn_t dim2_ahb_isr(int irq, void *_dev)
{
	struct dim2_hdm *dev = _dev;
	struct dim_channel *buffer[DMA_CHANNELS + 1];
	unsigned long flags;

	spin_lock_irqsave(&dim_lock, flags);
	dim_service_ahb_int_irq(get_active_channels(dev, buffer));
	spin_unlock_irqrestore(&dim_lock, flags);

	dim2_tasklet.data = (unsigned long)dev;
	tasklet_schedule(&dim2_tasklet);
	return IRQ_HANDLED;
}

/**
 * complete_all_mbos - complete MBO's in a list
 * @head: list head
 *
 * Delete all the entries in list and return back MBO's to mostcore using
 * completion call back.
 */
static void complete_all_mbos(struct list_head *head)
{
	unsigned long flags;
	struct mbo *mbo;

	for (;;) {
		spin_lock_irqsave(&dim_lock, flags);
		if (list_empty(head)) {
			spin_unlock_irqrestore(&dim_lock, flags);
			break;
		}

		mbo = list_first_entry(head, struct mbo, list);
		list_del(head->next);
		spin_unlock_irqrestore(&dim_lock, flags);

		mbo->processed_length = 0;
		mbo->status = MBO_E_CLOSE;
		mbo->complete(mbo);
	}
}

/**
 * configure_channel - initialize a channel
 * @iface: interface the channel belongs to
 * @channel: channel to be configured
 * @channel_config: structure that holds the configuration information
 *
 * Receives configuration information from mostcore and initialize
 * the corresponding channel. Return 0 on success, negative on failure.
 */
static int configure_channel(struct most_interface *most_iface, int ch_idx,
			     struct most_channel_config *ccfg)
{
	struct dim2_hdm *dev = iface_to_hdm(most_iface);
	bool const is_tx = ccfg->direction == MOST_CH_TX;
	u16 const sub_size = ccfg->subbuffer_size;
	u16 const buf_size = ccfg->buffer_size;
	u16 new_size;
	unsigned long flags;
	u8 hal_ret;
	int const ch_addr = ch_idx * 2 + 2;
	struct hdm_channel *const hdm_ch = dev->hch + ch_idx;

	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);

	if (hdm_ch->is_initialized)
		return -EPERM;

	switch (ccfg->data_type) {
	case MOST_CH_CONTROL:
		new_size = dim_norm_ctrl_async_buffer_size(buf_size);
		if (new_size == 0) {
			pr_err("%s: too small buffer size\n", hdm_ch->name);
			return -EINVAL;
		}
		ccfg->buffer_size = new_size;
		if (new_size != buf_size)
			pr_warn("%s: fixed buffer size (%d -> %d)\n",
				hdm_ch->name, buf_size, new_size);
		spin_lock_irqsave(&dim_lock, flags);
		hal_ret = dim_init_control(&hdm_ch->ch, is_tx, ch_addr,
					   is_tx ? new_size * 2 : new_size);
		break;
	case MOST_CH_ASYNC:
		new_size = dim_norm_ctrl_async_buffer_size(buf_size);
		if (new_size == 0) {
			pr_err("%s: too small buffer size\n", hdm_ch->name);
			return -EINVAL;
		}
		ccfg->buffer_size = new_size;
		if (new_size != buf_size)
			pr_warn("%s: fixed buffer size (%d -> %d)\n",
				hdm_ch->name, buf_size, new_size);
		spin_lock_irqsave(&dim_lock, flags);
		hal_ret = dim_init_async(&hdm_ch->ch, is_tx, ch_addr,
					 is_tx ? new_size * 2 : new_size);
		break;
	case MOST_CH_ISOC:
		new_size = dim_norm_isoc_buffer_size(buf_size, sub_size);
		if (new_size == 0) {
			pr_err("%s: invalid sub-buffer size or too small buffer size\n",
			       hdm_ch->name);
			return -EINVAL;
		}
		ccfg->buffer_size = new_size;
		if (new_size != buf_size)
			pr_warn("%s: fixed buffer size (%d -> %d)\n",
				hdm_ch->name, buf_size, new_size);
		spin_lock_irqsave(&dim_lock, flags);
		hal_ret = dim_init_isoc(&hdm_ch->ch, is_tx, ch_addr, sub_size);
		break;
	case MOST_CH_SYNC:
		new_size = dim_norm_sync_buffer_size(buf_size, sub_size);
		if (new_size == 0) {
			pr_err("%s: invalid sub-buffer size or too small buffer size\n",
			       hdm_ch->name);
			return -EINVAL;
		}
		ccfg->buffer_size = new_size;
		if (new_size != buf_size)
			pr_warn("%s: fixed buffer size (%d -> %d)\n",
				hdm_ch->name, buf_size, new_size);
		spin_lock_irqsave(&dim_lock, flags);
		hal_ret = dim_init_sync(&hdm_ch->ch, is_tx, ch_addr, sub_size);
		break;
	default:
		pr_err("%s: configure failed, bad channel type: %d\n",
		       hdm_ch->name, ccfg->data_type);
		return -EINVAL;
	}

	if (hal_ret != DIM_NO_ERROR) {
		spin_unlock_irqrestore(&dim_lock, flags);
		pr_err("%s: configure failed (%d), type: %d, is_tx: %d\n",
		       hdm_ch->name, hal_ret, ccfg->data_type, (int)is_tx);
		return -ENODEV;
	}

	hdm_ch->data_type = ccfg->data_type;
	hdm_ch->direction = ccfg->direction;
	hdm_ch->is_initialized = true;

	if (hdm_ch->data_type == MOST_CH_ASYNC &&
	    hdm_ch->direction == MOST_CH_TX &&
	    dev->atx_idx < 0)
		dev->atx_idx = ch_idx;

	spin_unlock_irqrestore(&dim_lock, flags);

	return 0;
}

/**
 * enqueue - enqueue a buffer for data transfer
 * @iface: intended interface
 * @channel: ID of the channel the buffer is intended for
 * @mbo: pointer to the buffer object
 *
 * Push the buffer into pending_list and try to transfer one buffer from
 * pending_list. Return 0 on success, negative on failure.
 */
static int enqueue(struct most_interface *most_iface, int ch_idx,
		   struct mbo *mbo)
{
	struct dim2_hdm *dev = iface_to_hdm(most_iface);
	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
	unsigned long flags;

	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);

	if (!hdm_ch->is_initialized)
		return -EPERM;

	if (mbo->bus_address == 0)
		return -EFAULT;

	spin_lock_irqsave(&dim_lock, flags);
	list_add_tail(&mbo->list, &hdm_ch->pending_list);
	spin_unlock_irqrestore(&dim_lock, flags);

	(void)try_start_dim_transfer(hdm_ch);

	return 0;
}

/**
 * request_netinfo - triggers retrieving of network info
 * @iface: pointer to the interface
 * @channel_id: corresponding channel ID
 *
 * Send a command to INIC which triggers retrieving of network info by means of
 * "Message exchange over MDP/MEP". Return 0 on success, negative on failure.
 */
static void request_netinfo(struct most_interface *most_iface, int ch_idx)
{
	struct dim2_hdm *dev = iface_to_hdm(most_iface);
	struct mbo *mbo;
	u8 *data;

	if (dev->atx_idx < 0) {
		pr_err("Async Tx Not initialized\n");
		return;
	}

	mbo = most_get_mbo(&dev->most_iface, dev->atx_idx, NULL);
	if (!mbo)
		return;

	mbo->buffer_length = 5;

	data = mbo->virt_address;

	data[0] = 0x00; /* PML High byte */
	data[1] = 0x03; /* PML Low byte */
	data[2] = 0x02; /* PMHL */
	data[3] = 0x08; /* FPH */
	data[4] = 0x40; /* FMF (FIFO cmd msg - Triggers NAOverMDP) */

	most_submit_mbo(mbo);
}

/**
 * poison_channel - poison buffers of a channel
 * @iface: pointer to the interface the channel to be poisoned belongs to
 * @channel_id: corresponding channel ID
 *
 * Destroy a channel and complete all the buffers in both started_list &
 * pending_list. Return 0 on success, negative on failure.
 */
static int poison_channel(struct most_interface *most_iface, int ch_idx)
{
	struct dim2_hdm *dev = iface_to_hdm(most_iface);
	struct hdm_channel *hdm_ch = dev->hch + ch_idx;
	unsigned long flags;
	u8 hal_ret;
	int ret = 0;

	BUG_ON(ch_idx < 0 || ch_idx >= DMA_CHANNELS);

	if (!hdm_ch->is_initialized)
		return -EPERM;

	tasklet_disable(&dim2_tasklet);
	spin_lock_irqsave(&dim_lock, flags);
	hal_ret = dim_destroy_channel(&hdm_ch->ch);
	hdm_ch->is_initialized = false;
	if (ch_idx == dev->atx_idx)
		dev->atx_idx = -1;
	spin_unlock_irqrestore(&dim_lock, flags);
	tasklet_enable(&dim2_tasklet);
	if (hal_ret != DIM_NO_ERROR) {
		pr_err("HAL Failed to close channel %s\n", hdm_ch->name);
		ret = -EFAULT;
	}

	complete_all_mbos(&hdm_ch->started_list);
	complete_all_mbos(&hdm_ch->pending_list);

	return ret;
}

/*
 * dim2_probe - dim2 probe handler
 * @pdev: platform device structure
 *
 * Register the dim2 interface with mostcore and initialize it.
 * Return 0 on success, negative on failure.
 */
static int dim2_probe(struct platform_device *pdev)
{
	struct dim2_hdm *dev;
	struct resource *res;
	int ret, i;
	struct kobject *kobj;
	int irq;

	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	dev->atx_idx = -1;

	platform_set_drvdata(pdev, dev);
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	dev->io_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(dev->io_base))
		return PTR_ERR(dev->io_base);

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "failed to get ahb0_int irq\n");
		return -ENODEV;
	}

	ret = devm_request_irq(&pdev->dev, irq, dim2_ahb_isr, 0,
			       "dim2_ahb0_int", dev);
	if (ret) {
		dev_err(&pdev->dev, "failed to request ahb0_int irq %d\n", irq);
		return ret;
	}

	irq = platform_get_irq(pdev, 1);
	if (irq < 0) {
		dev_err(&pdev->dev, "failed to get mlb_int irq\n");
		return -ENODEV;
	}

	ret = devm_request_irq(&pdev->dev, irq, dim2_mlb_isr, 0,
			       "dim2_mlb_int", dev);
	if (ret) {
		dev_err(&pdev->dev, "failed to request mlb_int irq %d\n", irq);
		return ret;
	}

	init_waitqueue_head(&dev->netinfo_waitq);
	dev->deliver_netinfo = 0;
	dev->netinfo_task = kthread_run(&deliver_netinfo_thread, (void *)dev,
					"dim2_netinfo");
	if (IS_ERR(dev->netinfo_task))
		return PTR_ERR(dev->netinfo_task);

	for (i = 0; i < DMA_CHANNELS; i++) {
		struct most_channel_capability *cap = dev->capabilities + i;
		struct hdm_channel *hdm_ch = dev->hch + i;

		INIT_LIST_HEAD(&hdm_ch->pending_list);
		INIT_LIST_HEAD(&hdm_ch->started_list);
		hdm_ch->is_initialized = false;
		snprintf(hdm_ch->name, sizeof(hdm_ch->name), "ca%d", i * 2 + 2);

		cap->name_suffix = hdm_ch->name;
		cap->direction = MOST_CH_RX | MOST_CH_TX;
		cap->data_type = MOST_CH_CONTROL | MOST_CH_ASYNC |
				 MOST_CH_ISOC | MOST_CH_SYNC;
		cap->num_buffers_packet = MAX_BUFFERS_PACKET;
		cap->buffer_size_packet = MAX_BUF_SIZE_PACKET;
		cap->num_buffers_streaming = MAX_BUFFERS_STREAMING;
		cap->buffer_size_streaming = MAX_BUF_SIZE_STREAMING;
	}

	{
		const char *fmt;

		if (sizeof(res->start) == sizeof(long long))
			fmt = "dim2-%016llx";
		else if (sizeof(res->start) == sizeof(long))
			fmt = "dim2-%016lx";
		else
			fmt = "dim2-%016x";

		snprintf(dev->name, sizeof(dev->name), fmt, res->start);
	}

	dev->most_iface.interface = ITYPE_MEDIALB_DIM2;
	dev->most_iface.description = dev->name;
	dev->most_iface.num_channels = DMA_CHANNELS;
	dev->most_iface.channel_vector = dev->capabilities;
	dev->most_iface.configure = configure_channel;
	dev->most_iface.enqueue = enqueue;
	dev->most_iface.poison_channel = poison_channel;
	dev->most_iface.request_netinfo = request_netinfo;

	kobj = most_register_interface(&dev->most_iface);
	if (IS_ERR(kobj)) {
		ret = PTR_ERR(kobj);
		dev_err(&pdev->dev, "failed to register MOST interface\n");
		goto err_stop_thread;
	}

	ret = dim2_sysfs_probe(&dev->bus, kobj);
	if (ret)
		goto err_unreg_iface;

	ret = startup_dim(pdev);
	if (ret) {
		dev_err(&pdev->dev, "failed to initialize DIM2\n");
		goto err_destroy_bus;
	}

	return 0;

err_destroy_bus:
	dim2_sysfs_destroy(&dev->bus);
err_unreg_iface:
	most_deregister_interface(&dev->most_iface);
err_stop_thread:
	kthread_stop(dev->netinfo_task);

	return ret;
}

/**
 * dim2_remove - dim2 remove handler
 * @pdev: platform device structure
 *
 * Unregister the interface from mostcore
 */
static int dim2_remove(struct platform_device *pdev)
{
	struct dim2_hdm *dev = platform_get_drvdata(pdev);
	struct dim2_platform_data *pdata = pdev->dev.platform_data;
	unsigned long flags;

	spin_lock_irqsave(&dim_lock, flags);
	dim_shutdown();
	spin_unlock_irqrestore(&dim_lock, flags);

	if (pdata && pdata->destroy)
		pdata->destroy(pdata);

	dim2_sysfs_destroy(&dev->bus);
	most_deregister_interface(&dev->most_iface);
	kthread_stop(dev->netinfo_task);

	/*
	 * break link to local platform_device_id struct
	 * to prevent crash by unload platform device module
	 */
	pdev->id_entry = NULL;

	return 0;
}

static struct platform_device_id dim2_id[] = {
	{ "medialb_dim2" },
	{ }, /* Terminating entry */
};

MODULE_DEVICE_TABLE(platform, dim2_id);

static struct platform_driver dim2_driver = {
	.probe = dim2_probe,
	.remove = dim2_remove,
	.id_table = dim2_id,
	.driver = {
		.name = "hdm_dim2",
	},
};

module_platform_driver(dim2_driver);

MODULE_AUTHOR("Jain Roy Ambi <JainRoy.Ambi@microchip.com>");
MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
MODULE_DESCRIPTION("MediaLB DIM2 Hardware Dependent Module");
MODULE_LICENSE("GPL");