summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
blob: cb5ce73f72694ad2d7547527f8581c9f9b786a50 (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
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
/*
 * DMM IOMMU driver support functions for TI OMAP processors.
 *
 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
 * Author: Rob Clark <rob@ti.com>
 *         Andy Gross <andy.gross@ti.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h> /* platform_device() */
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>

#include "omap_dmm_tiler.h"
#include "omap_dmm_priv.h"

#define DMM_DRIVER_NAME "dmm"

/* mappings for associating views to luts */
static struct tcm *containers[TILFMT_NFORMATS];
static struct dmm *omap_dmm;

#if defined(CONFIG_OF)
static const struct of_device_id dmm_of_match[];
#endif

/* global spinlock for protecting lists */
static DEFINE_SPINLOCK(list_lock);

/* Geometry table */
#define GEOM(xshift, yshift, bytes_per_pixel) { \
		.x_shft = (xshift), \
		.y_shft = (yshift), \
		.cpp    = (bytes_per_pixel), \
		.slot_w = 1 << (SLOT_WIDTH_BITS - (xshift)), \
		.slot_h = 1 << (SLOT_HEIGHT_BITS - (yshift)), \
	}

static const struct {
	u32 x_shft;	/* unused X-bits (as part of bpp) */
	u32 y_shft;	/* unused Y-bits (as part of bpp) */
	u32 cpp;		/* bytes/chars per pixel */
	u32 slot_w;	/* width of each slot (in pixels) */
	u32 slot_h;	/* height of each slot (in pixels) */
} geom[TILFMT_NFORMATS] = {
	[TILFMT_8BIT]  = GEOM(0, 0, 1),
	[TILFMT_16BIT] = GEOM(0, 1, 2),
	[TILFMT_32BIT] = GEOM(1, 1, 4),
	[TILFMT_PAGE]  = GEOM(SLOT_WIDTH_BITS, SLOT_HEIGHT_BITS, 1),
};


/* lookup table for registers w/ per-engine instances */
static const u32 reg[][4] = {
	[PAT_STATUS] = {DMM_PAT_STATUS__0, DMM_PAT_STATUS__1,
			DMM_PAT_STATUS__2, DMM_PAT_STATUS__3},
	[PAT_DESCR]  = {DMM_PAT_DESCR__0, DMM_PAT_DESCR__1,
			DMM_PAT_DESCR__2, DMM_PAT_DESCR__3},
};

static u32 dmm_read(struct dmm *dmm, u32 reg)
{
	return readl(dmm->base + reg);
}

static void dmm_write(struct dmm *dmm, u32 val, u32 reg)
{
	writel(val, dmm->base + reg);
}

/* simple allocator to grab next 16 byte aligned memory from txn */
static void *alloc_dma(struct dmm_txn *txn, size_t sz, dma_addr_t *pa)
{
	void *ptr;
	struct refill_engine *engine = txn->engine_handle;

	/* dmm programming requires 16 byte aligned addresses */
	txn->current_pa = round_up(txn->current_pa, 16);
	txn->current_va = (void *)round_up((long)txn->current_va, 16);

	ptr = txn->current_va;
	*pa = txn->current_pa;

	txn->current_pa += sz;
	txn->current_va += sz;

	BUG_ON((txn->current_va - engine->refill_va) > REFILL_BUFFER_SIZE);

	return ptr;
}

/* check status and spin until wait_mask comes true */
static int wait_status(struct refill_engine *engine, u32 wait_mask)
{
	struct dmm *dmm = engine->dmm;
	u32 r = 0, err, i;

	i = DMM_FIXED_RETRY_COUNT;
	while (true) {
		r = dmm_read(dmm, reg[PAT_STATUS][engine->id]);
		err = r & DMM_PATSTATUS_ERR;
		if (err) {
			dev_err(dmm->dev,
				"%s: error (engine%d). PAT_STATUS: 0x%08x\n",
				__func__, engine->id, r);
			return -EFAULT;
		}

		if ((r & wait_mask) == wait_mask)
			break;

		if (--i == 0) {
			dev_err(dmm->dev,
				"%s: timeout (engine%d). PAT_STATUS: 0x%08x\n",
				__func__, engine->id, r);
			return -ETIMEDOUT;
		}

		udelay(1);
	}

	return 0;
}

static void release_engine(struct refill_engine *engine)
{
	unsigned long flags;

	spin_lock_irqsave(&list_lock, flags);
	list_add(&engine->idle_node, &omap_dmm->idle_head);
	spin_unlock_irqrestore(&list_lock, flags);

	atomic_inc(&omap_dmm->engine_counter);
	wake_up_interruptible(&omap_dmm->engine_queue);
}

static irqreturn_t omap_dmm_irq_handler(int irq, void *arg)
{
	struct dmm *dmm = arg;
	u32 status = dmm_read(dmm, DMM_PAT_IRQSTATUS);
	int i;

	/* ack IRQ */
	dmm_write(dmm, status, DMM_PAT_IRQSTATUS);

	for (i = 0; i < dmm->num_engines; i++) {
		if (status & DMM_IRQSTAT_ERR_MASK)
			dev_err(dmm->dev,
				"irq error(engine%d): IRQSTAT 0x%02x\n",
				i, status & 0xff);

		if (status & DMM_IRQSTAT_LST) {
			if (dmm->engines[i].async)
				release_engine(&dmm->engines[i]);

			complete(&dmm->engines[i].compl);
		}

		status >>= 8;
	}

	return IRQ_HANDLED;
}

/**
 * Get a handle for a DMM transaction
 */
static struct dmm_txn *dmm_txn_init(struct dmm *dmm, struct tcm *tcm)
{
	struct dmm_txn *txn = NULL;
	struct refill_engine *engine = NULL;
	int ret;
	unsigned long flags;


	/* wait until an engine is available */
	ret = wait_event_interruptible(omap_dmm->engine_queue,
		atomic_add_unless(&omap_dmm->engine_counter, -1, 0));
	if (ret)
		return ERR_PTR(ret);

	/* grab an idle engine */
	spin_lock_irqsave(&list_lock, flags);
	if (!list_empty(&dmm->idle_head)) {
		engine = list_entry(dmm->idle_head.next, struct refill_engine,
					idle_node);
		list_del(&engine->idle_node);
	}
	spin_unlock_irqrestore(&list_lock, flags);

	BUG_ON(!engine);

	txn = &engine->txn;
	engine->tcm = tcm;
	txn->engine_handle = engine;
	txn->last_pat = NULL;
	txn->current_va = engine->refill_va;
	txn->current_pa = engine->refill_pa;

	return txn;
}

/**
 * Add region to DMM transaction.  If pages or pages[i] is NULL, then the
 * corresponding slot is cleared (ie. dummy_pa is programmed)
 */
static void dmm_txn_append(struct dmm_txn *txn, struct pat_area *area,
		struct page **pages, u32 npages, u32 roll)
{
	dma_addr_t pat_pa = 0, data_pa = 0;
	u32 *data;
	struct pat *pat;
	struct refill_engine *engine = txn->engine_handle;
	int columns = (1 + area->x1 - area->x0);
	int rows = (1 + area->y1 - area->y0);
	int i = columns*rows;

	pat = alloc_dma(txn, sizeof(*pat), &pat_pa);

	if (txn->last_pat)
		txn->last_pat->next_pa = (u32)pat_pa;

	pat->area = *area;

	/* adjust Y coordinates based off of container parameters */
	pat->area.y0 += engine->tcm->y_offset;
	pat->area.y1 += engine->tcm->y_offset;

	pat->ctrl = (struct pat_ctrl){
			.start = 1,
			.lut_id = engine->tcm->lut_id,
		};

	data = alloc_dma(txn, 4*i, &data_pa);
	/* FIXME: what if data_pa is more than 32-bit ? */
	pat->data_pa = data_pa;

	while (i--) {
		int n = i + roll;
		if (n >= npages)
			n -= npages;
		data[i] = (pages && pages[n]) ?
			page_to_phys(pages[n]) : engine->dmm->dummy_pa;
	}

	txn->last_pat = pat;

	return;
}

/**
 * Commit the DMM transaction.
 */
static int dmm_txn_commit(struct dmm_txn *txn, bool wait)
{
	int ret = 0;
	struct refill_engine *engine = txn->engine_handle;
	struct dmm *dmm = engine->dmm;

	if (!txn->last_pat) {
		dev_err(engine->dmm->dev, "need at least one txn\n");
		ret = -EINVAL;
		goto cleanup;
	}

	txn->last_pat->next_pa = 0;
	/* ensure that the written descriptors are visible to DMM */
	wmb();

	/*
	 * NOTE: the wmb() above should be enough, but there seems to be a bug
	 * in OMAP's memory barrier implementation, which in some rare cases may
	 * cause the writes not to be observable after wmb().
	 */

	/* read back to ensure the data is in RAM */
	readl(&txn->last_pat->next_pa);

	/* write to PAT_DESCR to clear out any pending transaction */
	dmm_write(dmm, 0x0, reg[PAT_DESCR][engine->id]);

	/* wait for engine ready: */
	ret = wait_status(engine, DMM_PATSTATUS_READY);
	if (ret) {
		ret = -EFAULT;
		goto cleanup;
	}

	/* mark whether it is async to denote list management in IRQ handler */
	engine->async = wait ? false : true;
	reinit_completion(&engine->compl);
	/* verify that the irq handler sees the 'async' and completion value */
	smp_mb();

	/* kick reload */
	dmm_write(dmm, engine->refill_pa, reg[PAT_DESCR][engine->id]);

	if (wait) {
		if (!wait_for_completion_timeout(&engine->compl,
				msecs_to_jiffies(100))) {
			dev_err(dmm->dev, "timed out waiting for done\n");
			ret = -ETIMEDOUT;
			goto cleanup;
		}

		/* Check the engine status before continue */
		ret = wait_status(engine, DMM_PATSTATUS_READY |
				  DMM_PATSTATUS_VALID | DMM_PATSTATUS_DONE);
	}

cleanup:
	/* only place engine back on list if we are done with it */
	if (ret || wait)
		release_engine(engine);

	return ret;
}

/*
 * DMM programming
 */
static int fill(struct tcm_area *area, struct page **pages,
		u32 npages, u32 roll, bool wait)
{
	int ret = 0;
	struct tcm_area slice, area_s;
	struct dmm_txn *txn;

	/*
	 * FIXME
	 *
	 * Asynchronous fill does not work reliably, as the driver does not
	 * handle errors in the async code paths. The fill operation may
	 * silently fail, leading to leaking DMM engines, which may eventually
	 * lead to deadlock if we run out of DMM engines.
	 *
	 * For now, always set 'wait' so that we only use sync fills. Async
	 * fills should be fixed, or alternatively we could decide to only
	 * support sync fills and so the whole async code path could be removed.
	 */

	wait = true;

	txn = dmm_txn_init(omap_dmm, area->tcm);
	if (IS_ERR_OR_NULL(txn))
		return -ENOMEM;

	tcm_for_each_slice(slice, *area, area_s) {
		struct pat_area p_area = {
				.x0 = slice.p0.x,  .y0 = slice.p0.y,
				.x1 = slice.p1.x,  .y1 = slice.p1.y,
		};

		dmm_txn_append(txn, &p_area, pages, npages, roll);

		roll += tcm_sizeof(slice);
	}

	ret = dmm_txn_commit(txn, wait);

	return ret;
}

/*
 * Pin/unpin
 */

/* note: slots for which pages[i] == NULL are filled w/ dummy page
 */
int tiler_pin(struct tiler_block *block, struct page **pages,
		u32 npages, u32 roll, bool wait)
{
	int ret;

	ret = fill(&block->area, pages, npages, roll, wait);

	if (ret)
		tiler_unpin(block);

	return ret;
}

int tiler_unpin(struct tiler_block *block)
{
	return fill(&block->area, NULL, 0, 0, false);
}

/*
 * Reserve/release
 */
struct tiler_block *tiler_reserve_2d(enum tiler_fmt fmt, u16 w,
		u16 h, u16 align)
{
	struct tiler_block *block;
	u32 min_align = 128;
	int ret;
	unsigned long flags;
	u32 slot_bytes;

	block = kzalloc(sizeof(*block), GFP_KERNEL);
	if (!block)
		return ERR_PTR(-ENOMEM);

	BUG_ON(!validfmt(fmt));

	/* convert width/height to slots */
	w = DIV_ROUND_UP(w, geom[fmt].slot_w);
	h = DIV_ROUND_UP(h, geom[fmt].slot_h);

	/* convert alignment to slots */
	slot_bytes = geom[fmt].slot_w * geom[fmt].cpp;
	min_align = max(min_align, slot_bytes);
	align = (align > min_align) ? ALIGN(align, min_align) : min_align;
	align /= slot_bytes;

	block->fmt = fmt;

	ret = tcm_reserve_2d(containers[fmt], w, h, align, -1, slot_bytes,
			&block->area);
	if (ret) {
		kfree(block);
		return ERR_PTR(-ENOMEM);
	}

	/* add to allocation list */
	spin_lock_irqsave(&list_lock, flags);
	list_add(&block->alloc_node, &omap_dmm->alloc_head);
	spin_unlock_irqrestore(&list_lock, flags);

	return block;
}

struct tiler_block *tiler_reserve_1d(size_t size)
{
	struct tiler_block *block = kzalloc(sizeof(*block), GFP_KERNEL);
	int num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
	unsigned long flags;

	if (!block)
		return ERR_PTR(-ENOMEM);

	block->fmt = TILFMT_PAGE;

	if (tcm_reserve_1d(containers[TILFMT_PAGE], num_pages,
				&block->area)) {
		kfree(block);
		return ERR_PTR(-ENOMEM);
	}

	spin_lock_irqsave(&list_lock, flags);
	list_add(&block->alloc_node, &omap_dmm->alloc_head);
	spin_unlock_irqrestore(&list_lock, flags);

	return block;
}

/* note: if you have pin'd pages, you should have already unpin'd first! */
int tiler_release(struct tiler_block *block)
{
	int ret = tcm_free(&block->area);
	unsigned long flags;

	if (block->area.tcm)
		dev_err(omap_dmm->dev, "failed to release block\n");

	spin_lock_irqsave(&list_lock, flags);
	list_del(&block->alloc_node);
	spin_unlock_irqrestore(&list_lock, flags);

	kfree(block);
	return ret;
}

/*
 * Utils
 */

/* calculate the tiler space address of a pixel in a view orientation...
 * below description copied from the display subsystem section of TRM:
 *
 * When the TILER is addressed, the bits:
 *   [28:27] = 0x0 for 8-bit tiled
 *             0x1 for 16-bit tiled
 *             0x2 for 32-bit tiled
 *             0x3 for page mode
 *   [31:29] = 0x0 for 0-degree view
 *             0x1 for 180-degree view + mirroring
 *             0x2 for 0-degree view + mirroring
 *             0x3 for 180-degree view
 *             0x4 for 270-degree view + mirroring
 *             0x5 for 270-degree view
 *             0x6 for 90-degree view
 *             0x7 for 90-degree view + mirroring
 * Otherwise the bits indicated the corresponding bit address to access
 * the SDRAM.
 */
static u32 tiler_get_address(enum tiler_fmt fmt, u32 orient, u32 x, u32 y)
{
	u32 x_bits, y_bits, tmp, x_mask, y_mask, alignment;

	x_bits = CONT_WIDTH_BITS - geom[fmt].x_shft;
	y_bits = CONT_HEIGHT_BITS - geom[fmt].y_shft;
	alignment = geom[fmt].x_shft + geom[fmt].y_shft;

	/* validate coordinate */
	x_mask = MASK(x_bits);
	y_mask = MASK(y_bits);

	if (x < 0 || x > x_mask || y < 0 || y > y_mask) {
		DBG("invalid coords: %u < 0 || %u > %u || %u < 0 || %u > %u",
				x, x, x_mask, y, y, y_mask);
		return 0;
	}

	/* account for mirroring */
	if (orient & MASK_X_INVERT)
		x ^= x_mask;
	if (orient & MASK_Y_INVERT)
		y ^= y_mask;

	/* get coordinate address */
	if (orient & MASK_XY_FLIP)
		tmp = ((x << y_bits) + y);
	else
		tmp = ((y << x_bits) + x);

	return TIL_ADDR((tmp << alignment), orient, fmt);
}

dma_addr_t tiler_ssptr(struct tiler_block *block)
{
	BUG_ON(!validfmt(block->fmt));

	return TILVIEW_8BIT + tiler_get_address(block->fmt, 0,
			block->area.p0.x * geom[block->fmt].slot_w,
			block->area.p0.y * geom[block->fmt].slot_h);
}

dma_addr_t tiler_tsptr(struct tiler_block *block, u32 orient,
		u32 x, u32 y)
{
	struct tcm_pt *p = &block->area.p0;
	BUG_ON(!validfmt(block->fmt));

	return tiler_get_address(block->fmt, orient,
			(p->x * geom[block->fmt].slot_w) + x,
			(p->y * geom[block->fmt].slot_h) + y);
}

void tiler_align(enum tiler_fmt fmt, u16 *w, u16 *h)
{
	BUG_ON(!validfmt(fmt));
	*w = round_up(*w, geom[fmt].slot_w);
	*h = round_up(*h, geom[fmt].slot_h);
}

u32 tiler_stride(enum tiler_fmt fmt, u32 orient)
{
	BUG_ON(!validfmt(fmt));

	if (orient & MASK_XY_FLIP)
		return 1 << (CONT_HEIGHT_BITS + geom[fmt].x_shft);
	else
		return 1 << (CONT_WIDTH_BITS + geom[fmt].y_shft);
}

size_t tiler_size(enum tiler_fmt fmt, u16 w, u16 h)
{
	tiler_align(fmt, &w, &h);
	return geom[fmt].cpp * w * h;
}

size_t tiler_vsize(enum tiler_fmt fmt, u16 w, u16 h)
{
	BUG_ON(!validfmt(fmt));
	return round_up(geom[fmt].cpp * w, PAGE_SIZE) * h;
}

u32 tiler_get_cpu_cache_flags(void)
{
	return omap_dmm->plat_data->cpu_cache_flags;
}

bool dmm_is_available(void)
{
	return omap_dmm ? true : false;
}

static int omap_dmm_remove(struct platform_device *dev)
{
	struct tiler_block *block, *_block;
	int i;
	unsigned long flags;

	if (omap_dmm) {
		/* free all area regions */
		spin_lock_irqsave(&list_lock, flags);
		list_for_each_entry_safe(block, _block, &omap_dmm->alloc_head,
					alloc_node) {
			list_del(&block->alloc_node);
			kfree(block);
		}
		spin_unlock_irqrestore(&list_lock, flags);

		for (i = 0; i < omap_dmm->num_lut; i++)
			if (omap_dmm->tcm && omap_dmm->tcm[i])
				omap_dmm->tcm[i]->deinit(omap_dmm->tcm[i]);
		kfree(omap_dmm->tcm);

		kfree(omap_dmm->engines);
		if (omap_dmm->refill_va)
			dma_free_wc(omap_dmm->dev,
				    REFILL_BUFFER_SIZE * omap_dmm->num_engines,
				    omap_dmm->refill_va, omap_dmm->refill_pa);
		if (omap_dmm->dummy_page)
			__free_page(omap_dmm->dummy_page);

		if (omap_dmm->irq > 0)
			free_irq(omap_dmm->irq, omap_dmm);

		iounmap(omap_dmm->base);
		kfree(omap_dmm);
		omap_dmm = NULL;
	}

	return 0;
}

static int omap_dmm_probe(struct platform_device *dev)
{
	int ret = -EFAULT, i;
	struct tcm_area area = {0};
	u32 hwinfo, pat_geom;
	struct resource *mem;

	omap_dmm = kzalloc(sizeof(*omap_dmm), GFP_KERNEL);
	if (!omap_dmm)
		goto fail;

	/* initialize lists */
	INIT_LIST_HEAD(&omap_dmm->alloc_head);
	INIT_LIST_HEAD(&omap_dmm->idle_head);

	init_waitqueue_head(&omap_dmm->engine_queue);

	if (dev->dev.of_node) {
		const struct of_device_id *match;

		match = of_match_node(dmm_of_match, dev->dev.of_node);
		if (!match) {
			dev_err(&dev->dev, "failed to find matching device node\n");
			ret = -ENODEV;
			goto fail;
		}

		omap_dmm->plat_data = match->data;
	}

	/* lookup hwmod data - base address and irq */
	mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
	if (!mem) {
		dev_err(&dev->dev, "failed to get base address resource\n");
		goto fail;
	}

	omap_dmm->base = ioremap(mem->start, SZ_2K);

	if (!omap_dmm->base) {
		dev_err(&dev->dev, "failed to get dmm base address\n");
		goto fail;
	}

	omap_dmm->irq = platform_get_irq(dev, 0);
	if (omap_dmm->irq < 0) {
		dev_err(&dev->dev, "failed to get IRQ resource\n");
		goto fail;
	}

	omap_dmm->dev = &dev->dev;

	hwinfo = dmm_read(omap_dmm, DMM_PAT_HWINFO);
	omap_dmm->num_engines = (hwinfo >> 24) & 0x1F;
	omap_dmm->num_lut = (hwinfo >> 16) & 0x1F;
	omap_dmm->container_width = 256;
	omap_dmm->container_height = 128;

	atomic_set(&omap_dmm->engine_counter, omap_dmm->num_engines);

	/* read out actual LUT width and height */
	pat_geom = dmm_read(omap_dmm, DMM_PAT_GEOMETRY);
	omap_dmm->lut_width = ((pat_geom >> 16) & 0xF) << 5;
	omap_dmm->lut_height = ((pat_geom >> 24) & 0xF) << 5;

	/* increment LUT by one if on OMAP5 */
	/* LUT has twice the height, and is split into a separate container */
	if (omap_dmm->lut_height != omap_dmm->container_height)
		omap_dmm->num_lut++;

	/* initialize DMM registers */
	dmm_write(omap_dmm, 0x88888888, DMM_PAT_VIEW__0);
	dmm_write(omap_dmm, 0x88888888, DMM_PAT_VIEW__1);
	dmm_write(omap_dmm, 0x80808080, DMM_PAT_VIEW_MAP__0);
	dmm_write(omap_dmm, 0x80000000, DMM_PAT_VIEW_MAP_BASE);
	dmm_write(omap_dmm, 0x88888888, DMM_TILER_OR__0);
	dmm_write(omap_dmm, 0x88888888, DMM_TILER_OR__1);

	ret = request_irq(omap_dmm->irq, omap_dmm_irq_handler, IRQF_SHARED,
				"omap_dmm_irq_handler", omap_dmm);

	if (ret) {
		dev_err(&dev->dev, "couldn't register IRQ %d, error %d\n",
			omap_dmm->irq, ret);
		omap_dmm->irq = -1;
		goto fail;
	}

	/* Enable all interrupts for each refill engine except
	 * ERR_LUT_MISS<n> (which is just advisory, and we don't care
	 * about because we want to be able to refill live scanout
	 * buffers for accelerated pan/scroll) and FILL_DSC<n> which
	 * we just generally don't care about.
	 */
	dmm_write(omap_dmm, 0x7e7e7e7e, DMM_PAT_IRQENABLE_SET);

	omap_dmm->dummy_page = alloc_page(GFP_KERNEL | __GFP_DMA32);
	if (!omap_dmm->dummy_page) {
		dev_err(&dev->dev, "could not allocate dummy page\n");
		ret = -ENOMEM;
		goto fail;
	}

	/* set dma mask for device */
	ret = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32));
	if (ret)
		goto fail;

	omap_dmm->dummy_pa = page_to_phys(omap_dmm->dummy_page);

	/* alloc refill memory */
	omap_dmm->refill_va = dma_alloc_wc(&dev->dev,
					   REFILL_BUFFER_SIZE * omap_dmm->num_engines,
					   &omap_dmm->refill_pa, GFP_KERNEL);
	if (!omap_dmm->refill_va) {
		dev_err(&dev->dev, "could not allocate refill memory\n");
		ret = -ENOMEM;
		goto fail;
	}

	/* alloc engines */
	omap_dmm->engines = kcalloc(omap_dmm->num_engines,
				    sizeof(*omap_dmm->engines), GFP_KERNEL);
	if (!omap_dmm->engines) {
		ret = -ENOMEM;
		goto fail;
	}

	for (i = 0; i < omap_dmm->num_engines; i++) {
		omap_dmm->engines[i].id = i;
		omap_dmm->engines[i].dmm = omap_dmm;
		omap_dmm->engines[i].refill_va = omap_dmm->refill_va +
						(REFILL_BUFFER_SIZE * i);
		omap_dmm->engines[i].refill_pa = omap_dmm->refill_pa +
						(REFILL_BUFFER_SIZE * i);
		init_completion(&omap_dmm->engines[i].compl);

		list_add(&omap_dmm->engines[i].idle_node, &omap_dmm->idle_head);
	}

	omap_dmm->tcm = kcalloc(omap_dmm->num_lut, sizeof(*omap_dmm->tcm),
				GFP_KERNEL);
	if (!omap_dmm->tcm) {
		ret = -ENOMEM;
		goto fail;
	}

	/* init containers */
	/* Each LUT is associated with a TCM (container manager).  We use the
	   lut_id to denote the lut_id used to identify the correct LUT for
	   programming during reill operations */
	for (i = 0; i < omap_dmm->num_lut; i++) {
		omap_dmm->tcm[i] = sita_init(omap_dmm->container_width,
						omap_dmm->container_height);

		if (!omap_dmm->tcm[i]) {
			dev_err(&dev->dev, "failed to allocate container\n");
			ret = -ENOMEM;
			goto fail;
		}

		omap_dmm->tcm[i]->lut_id = i;
	}

	/* assign access mode containers to applicable tcm container */
	/* OMAP 4 has 1 container for all 4 views */
	/* OMAP 5 has 2 containers, 1 for 2D and 1 for 1D */
	containers[TILFMT_8BIT] = omap_dmm->tcm[0];
	containers[TILFMT_16BIT] = omap_dmm->tcm[0];
	containers[TILFMT_32BIT] = omap_dmm->tcm[0];

	if (omap_dmm->container_height != omap_dmm->lut_height) {
		/* second LUT is used for PAGE mode.  Programming must use
		   y offset that is added to all y coordinates.  LUT id is still
		   0, because it is the same LUT, just the upper 128 lines */
		containers[TILFMT_PAGE] = omap_dmm->tcm[1];
		omap_dmm->tcm[1]->y_offset = OMAP5_LUT_OFFSET;
		omap_dmm->tcm[1]->lut_id = 0;
	} else {
		containers[TILFMT_PAGE] = omap_dmm->tcm[0];
	}

	area = (struct tcm_area) {
		.tcm = NULL,
		.p1.x = omap_dmm->container_width - 1,
		.p1.y = omap_dmm->container_height - 1,
	};

	/* initialize all LUTs to dummy page entries */
	for (i = 0; i < omap_dmm->num_lut; i++) {
		area.tcm = omap_dmm->tcm[i];
		if (fill(&area, NULL, 0, 0, true))
			dev_err(omap_dmm->dev, "refill failed");
	}

	dev_info(omap_dmm->dev, "initialized all PAT entries\n");

	return 0;

fail:
	if (omap_dmm_remove(dev))
		dev_err(&dev->dev, "cleanup failed\n");
	return ret;
}

/*
 * debugfs support
 */

#ifdef CONFIG_DEBUG_FS

static const char *alphabet = "abcdefghijklmnopqrstuvwxyz"
				"ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
static const char *special = ".,:;'\"`~!^-+";

static void fill_map(char **map, int xdiv, int ydiv, struct tcm_area *a,
							char c, bool ovw)
{
	int x, y;
	for (y = a->p0.y / ydiv; y <= a->p1.y / ydiv; y++)
		for (x = a->p0.x / xdiv; x <= a->p1.x / xdiv; x++)
			if (map[y][x] == ' ' || ovw)
				map[y][x] = c;
}

static void fill_map_pt(char **map, int xdiv, int ydiv, struct tcm_pt *p,
									char c)
{
	map[p->y / ydiv][p->x / xdiv] = c;
}

static char read_map_pt(char **map, int xdiv, int ydiv, struct tcm_pt *p)
{
	return map[p->y / ydiv][p->x / xdiv];
}

static int map_width(int xdiv, int x0, int x1)
{
	return (x1 / xdiv) - (x0 / xdiv) + 1;
}

static void text_map(char **map, int xdiv, char *nice, int yd, int x0, int x1)
{
	char *p = map[yd] + (x0 / xdiv);
	int w = (map_width(xdiv, x0, x1) - strlen(nice)) / 2;
	if (w >= 0) {
		p += w;
		while (*nice)
			*p++ = *nice++;
	}
}

static void map_1d_info(char **map, int xdiv, int ydiv, char *nice,
							struct tcm_area *a)
{
	sprintf(nice, "%dK", tcm_sizeof(*a) * 4);
	if (a->p0.y + 1 < a->p1.y) {
		text_map(map, xdiv, nice, (a->p0.y + a->p1.y) / 2 / ydiv, 0,
							256 - 1);
	} else if (a->p0.y < a->p1.y) {
		if (strlen(nice) < map_width(xdiv, a->p0.x, 256 - 1))
			text_map(map, xdiv, nice, a->p0.y / ydiv,
					a->p0.x + xdiv,	256 - 1);
		else if (strlen(nice) < map_width(xdiv, 0, a->p1.x))
			text_map(map, xdiv, nice, a->p1.y / ydiv,
					0, a->p1.y - xdiv);
	} else if (strlen(nice) + 1 < map_width(xdiv, a->p0.x, a->p1.x)) {
		text_map(map, xdiv, nice, a->p0.y / ydiv, a->p0.x, a->p1.x);
	}
}

static void map_2d_info(char **map, int xdiv, int ydiv, char *nice,
							struct tcm_area *a)
{
	sprintf(nice, "(%d*%d)", tcm_awidth(*a), tcm_aheight(*a));
	if (strlen(nice) + 1 < map_width(xdiv, a->p0.x, a->p1.x))
		text_map(map, xdiv, nice, (a->p0.y + a->p1.y) / 2 / ydiv,
							a->p0.x, a->p1.x);
}

int tiler_map_show(struct seq_file *s, void *arg)
{
	int xdiv = 2, ydiv = 1;
	char **map = NULL, *global_map;
	struct tiler_block *block;
	struct tcm_area a, p;
	int i;
	const char *m2d = alphabet;
	const char *a2d = special;
	const char *m2dp = m2d, *a2dp = a2d;
	char nice[128];
	int h_adj;
	int w_adj;
	unsigned long flags;
	int lut_idx;


	if (!omap_dmm) {
		/* early return if dmm/tiler device is not initialized */
		return 0;
	}

	h_adj = omap_dmm->container_height / ydiv;
	w_adj = omap_dmm->container_width / xdiv;

	map = kmalloc_array(h_adj, sizeof(*map), GFP_KERNEL);
	global_map = kmalloc_array(w_adj + 1, h_adj, GFP_KERNEL);

	if (!map || !global_map)
		goto error;

	for (lut_idx = 0; lut_idx < omap_dmm->num_lut; lut_idx++) {
		memset(map, 0, h_adj * sizeof(*map));
		memset(global_map, ' ', (w_adj + 1) * h_adj);

		for (i = 0; i < omap_dmm->container_height; i++) {
			map[i] = global_map + i * (w_adj + 1);
			map[i][w_adj] = 0;
		}

		spin_lock_irqsave(&list_lock, flags);

		list_for_each_entry(block, &omap_dmm->alloc_head, alloc_node) {
			if (block->area.tcm == omap_dmm->tcm[lut_idx]) {
				if (block->fmt != TILFMT_PAGE) {
					fill_map(map, xdiv, ydiv, &block->area,
						*m2dp, true);
					if (!*++a2dp)
						a2dp = a2d;
					if (!*++m2dp)
						m2dp = m2d;
					map_2d_info(map, xdiv, ydiv, nice,
							&block->area);
				} else {
					bool start = read_map_pt(map, xdiv,
						ydiv, &block->area.p0) == ' ';
					bool end = read_map_pt(map, xdiv, ydiv,
							&block->area.p1) == ' ';

					tcm_for_each_slice(a, block->area, p)
						fill_map(map, xdiv, ydiv, &a,
							'=', true);
					fill_map_pt(map, xdiv, ydiv,
							&block->area.p0,
							start ? '<' : 'X');
					fill_map_pt(map, xdiv, ydiv,
							&block->area.p1,
							end ? '>' : 'X');
					map_1d_info(map, xdiv, ydiv, nice,
							&block->area);
				}
			}
		}

		spin_unlock_irqrestore(&list_lock, flags);

		if (s) {
			seq_printf(s, "CONTAINER %d DUMP BEGIN\n", lut_idx);
			for (i = 0; i < 128; i++)
				seq_printf(s, "%03d:%s\n", i, map[i]);
			seq_printf(s, "CONTAINER %d DUMP END\n", lut_idx);
		} else {
			dev_dbg(omap_dmm->dev, "CONTAINER %d DUMP BEGIN\n",
				lut_idx);
			for (i = 0; i < 128; i++)
				dev_dbg(omap_dmm->dev, "%03d:%s\n", i, map[i]);
			dev_dbg(omap_dmm->dev, "CONTAINER %d DUMP END\n",
				lut_idx);
		}
	}

error:
	kfree(map);
	kfree(global_map);

	return 0;
}
#endif

#ifdef CONFIG_PM_SLEEP
static int omap_dmm_resume(struct device *dev)
{
	struct tcm_area area;
	int i;

	if (!omap_dmm)
		return -ENODEV;

	area = (struct tcm_area) {
		.tcm = NULL,
		.p1.x = omap_dmm->container_width - 1,
		.p1.y = omap_dmm->container_height - 1,
	};

	/* initialize all LUTs to dummy page entries */
	for (i = 0; i < omap_dmm->num_lut; i++) {
		area.tcm = omap_dmm->tcm[i];
		if (fill(&area, NULL, 0, 0, true))
			dev_err(dev, "refill failed");
	}

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(omap_dmm_pm_ops, NULL, omap_dmm_resume);

#if defined(CONFIG_OF)
static const struct dmm_platform_data dmm_omap4_platform_data = {
	.cpu_cache_flags = OMAP_BO_WC,
};

static const struct dmm_platform_data dmm_omap5_platform_data = {
	.cpu_cache_flags = OMAP_BO_UNCACHED,
};

static const struct of_device_id dmm_of_match[] = {
	{
		.compatible = "ti,omap4-dmm",
		.data = &dmm_omap4_platform_data,
	},
	{
		.compatible = "ti,omap5-dmm",
		.data = &dmm_omap5_platform_data,
	},
	{},
};
#endif

struct platform_driver omap_dmm_driver = {
	.probe = omap_dmm_probe,
	.remove = omap_dmm_remove,
	.driver = {
		.owner = THIS_MODULE,
		.name = DMM_DRIVER_NAME,
		.of_match_table = of_match_ptr(dmm_of_match),
		.pm = &omap_dmm_pm_ops,
	},
};

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Andy Gross <andy.gross@ti.com>");
MODULE_DESCRIPTION("OMAP DMM/Tiler Driver");