summaryrefslogtreecommitdiffstats
path: root/drivers/dma/imx-sdma.c
blob: 1eb3f0077403273ad7b1e9843b00f6746edf1cec (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
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
/*
 * drivers/dma/imx-sdma.c
 *
 * This file contains a driver for the Freescale Smart DMA engine
 *
 * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
 *
 * Based on code from Freescale:
 *
 * Copyright 2004-2009 Freescale Semiconductor, Inc. All Rights Reserved.
 *
 * The code contained herein is licensed under the GNU General Public
 * License. You may obtain a copy of the GNU General Public License
 * Version 2 or later at the following locations:
 *
 * http://www.opensource.org/licenses/gpl-license.html
 * http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/init.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/semaphore.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/firmware.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/dmaengine.h>

#include <asm/irq.h>
#include <mach/sdma.h>
#include <mach/dma.h>
#include <mach/hardware.h>

/* SDMA registers */
#define SDMA_H_C0PTR		0x000
#define SDMA_H_INTR		0x004
#define SDMA_H_STATSTOP		0x008
#define SDMA_H_START		0x00c
#define SDMA_H_EVTOVR		0x010
#define SDMA_H_DSPOVR		0x014
#define SDMA_H_HOSTOVR		0x018
#define SDMA_H_EVTPEND		0x01c
#define SDMA_H_DSPENBL		0x020
#define SDMA_H_RESET		0x024
#define SDMA_H_EVTERR		0x028
#define SDMA_H_INTRMSK		0x02c
#define SDMA_H_PSW		0x030
#define SDMA_H_EVTERRDBG	0x034
#define SDMA_H_CONFIG		0x038
#define SDMA_ONCE_ENB		0x040
#define SDMA_ONCE_DATA		0x044
#define SDMA_ONCE_INSTR		0x048
#define SDMA_ONCE_STAT		0x04c
#define SDMA_ONCE_CMD		0x050
#define SDMA_EVT_MIRROR		0x054
#define SDMA_ILLINSTADDR	0x058
#define SDMA_CHN0ADDR		0x05c
#define SDMA_ONCE_RTB		0x060
#define SDMA_XTRIG_CONF1	0x070
#define SDMA_XTRIG_CONF2	0x074
#define SDMA_CHNENBL0_V2	0x200
#define SDMA_CHNENBL0_V1	0x080
#define SDMA_CHNPRI_0		0x100

/*
 * Buffer descriptor status values.
 */
#define BD_DONE  0x01
#define BD_WRAP  0x02
#define BD_CONT  0x04
#define BD_INTR  0x08
#define BD_RROR  0x10
#define BD_LAST  0x20
#define BD_EXTD  0x80

/*
 * Data Node descriptor status values.
 */
#define DND_END_OF_FRAME  0x80
#define DND_END_OF_XFER   0x40
#define DND_DONE          0x20
#define DND_UNUSED        0x01

/*
 * IPCV2 descriptor status values.
 */
#define BD_IPCV2_END_OF_FRAME  0x40

#define IPCV2_MAX_NODES        50
/*
 * Error bit set in the CCB status field by the SDMA,
 * in setbd routine, in case of a transfer error
 */
#define DATA_ERROR  0x10000000

/*
 * Buffer descriptor commands.
 */
#define C0_ADDR             0x01
#define C0_LOAD             0x02
#define C0_DUMP             0x03
#define C0_SETCTX           0x07
#define C0_GETCTX           0x03
#define C0_SETDM            0x01
#define C0_SETPM            0x04
#define C0_GETDM            0x02
#define C0_GETPM            0x08
/*
 * Change endianness indicator in the BD command field
 */
#define CHANGE_ENDIANNESS   0x80

/*
 * Mode/Count of data node descriptors - IPCv2
 */
struct sdma_mode_count {
	u32 count   : 16; /* size of the buffer pointed by this BD */
	u32 status  :  8; /* E,R,I,C,W,D status bits stored here */
	u32 command :  8; /* command mostlky used for channel 0 */
};

/*
 * Buffer descriptor
 */
struct sdma_buffer_descriptor {
	struct sdma_mode_count  mode;
	u32 buffer_addr;	/* address of the buffer described */
	u32 ext_buffer_addr;	/* extended buffer address */
} __attribute__ ((packed));

/**
 * struct sdma_channel_control - Channel control Block
 *
 * @current_bd_ptr	current buffer descriptor processed
 * @base_bd_ptr		first element of buffer descriptor array
 * @unused		padding. The SDMA engine expects an array of 128 byte
 *			control blocks
 */
struct sdma_channel_control {
	u32 current_bd_ptr;
	u32 base_bd_ptr;
	u32 unused[2];
} __attribute__ ((packed));

/**
 * struct sdma_state_registers - SDMA context for a channel
 *
 * @pc:		program counter
 * @t:		test bit: status of arithmetic & test instruction
 * @rpc:	return program counter
 * @sf:		source fault while loading data
 * @spc:	loop start program counter
 * @df:		destination fault while storing data
 * @epc:	loop end program counter
 * @lm:		loop mode
 */
struct sdma_state_registers {
	u32 pc     :14;
	u32 unused1: 1;
	u32 t      : 1;
	u32 rpc    :14;
	u32 unused0: 1;
	u32 sf     : 1;
	u32 spc    :14;
	u32 unused2: 1;
	u32 df     : 1;
	u32 epc    :14;
	u32 lm     : 2;
} __attribute__ ((packed));

/**
 * struct sdma_context_data - sdma context specific to a channel
 *
 * @channel_state:	channel state bits
 * @gReg:		general registers
 * @mda:		burst dma destination address register
 * @msa:		burst dma source address register
 * @ms:			burst dma status register
 * @md:			burst dma data register
 * @pda:		peripheral dma destination address register
 * @psa:		peripheral dma source address register
 * @ps:			peripheral dma status register
 * @pd:			peripheral dma data register
 * @ca:			CRC polynomial register
 * @cs:			CRC accumulator register
 * @dda:		dedicated core destination address register
 * @dsa:		dedicated core source address register
 * @ds:			dedicated core status register
 * @dd:			dedicated core data register
 */
struct sdma_context_data {
	struct sdma_state_registers  channel_state;
	u32  gReg[8];
	u32  mda;
	u32  msa;
	u32  ms;
	u32  md;
	u32  pda;
	u32  psa;
	u32  ps;
	u32  pd;
	u32  ca;
	u32  cs;
	u32  dda;
	u32  dsa;
	u32  ds;
	u32  dd;
	u32  scratch0;
	u32  scratch1;
	u32  scratch2;
	u32  scratch3;
	u32  scratch4;
	u32  scratch5;
	u32  scratch6;
	u32  scratch7;
} __attribute__ ((packed));

#define NUM_BD (int)(PAGE_SIZE / sizeof(struct sdma_buffer_descriptor))

struct sdma_engine;

/**
 * struct sdma_channel - housekeeping for a SDMA channel
 *
 * @sdma		pointer to the SDMA engine for this channel
 * @channel		the channel number, matches dmaengine chan_id + 1
 * @direction		transfer type. Needed for setting SDMA script
 * @peripheral_type	Peripheral type. Needed for setting SDMA script
 * @event_id0		aka dma request line
 * @event_id1		for channels that use 2 events
 * @word_size		peripheral access size
 * @buf_tail		ID of the buffer that was processed
 * @done		channel completion
 * @num_bd		max NUM_BD. number of descriptors currently handling
 */
struct sdma_channel {
	struct sdma_engine		*sdma;
	unsigned int			channel;
	enum dma_data_direction		direction;
	enum sdma_peripheral_type	peripheral_type;
	unsigned int			event_id0;
	unsigned int			event_id1;
	enum dma_slave_buswidth		word_size;
	unsigned int			buf_tail;
	struct completion		done;
	unsigned int			num_bd;
	struct sdma_buffer_descriptor	*bd;
	dma_addr_t			bd_phys;
	unsigned int			pc_from_device, pc_to_device;
	unsigned long			flags;
	dma_addr_t			per_address;
	u32				event_mask0, event_mask1;
	u32				watermark_level;
	u32				shp_addr, per_addr;
	struct dma_chan			chan;
	spinlock_t			lock;
	struct dma_async_tx_descriptor	desc;
	dma_cookie_t			last_completed;
	enum dma_status			status;
};

#define IMX_DMA_SG_LOOP		(1 << 0)

#define MAX_DMA_CHANNELS 32
#define MXC_SDMA_DEFAULT_PRIORITY 1
#define MXC_SDMA_MIN_PRIORITY 1
#define MXC_SDMA_MAX_PRIORITY 7

#define SDMA_FIRMWARE_MAGIC 0x414d4453

/**
 * struct sdma_firmware_header - Layout of the firmware image
 *
 * @magic		"SDMA"
 * @version_major	increased whenever layout of struct sdma_script_start_addrs
 *			changes.
 * @version_minor	firmware minor version (for binary compatible changes)
 * @script_addrs_start	offset of struct sdma_script_start_addrs in this image
 * @num_script_addrs	Number of script addresses in this image
 * @ram_code_start	offset of SDMA ram image in this firmware image
 * @ram_code_size	size of SDMA ram image
 * @script_addrs	Stores the start address of the SDMA scripts
 *			(in SDMA memory space)
 */
struct sdma_firmware_header {
	u32	magic;
	u32	version_major;
	u32	version_minor;
	u32	script_addrs_start;
	u32	num_script_addrs;
	u32	ram_code_start;
	u32	ram_code_size;
};

struct sdma_engine {
	struct device			*dev;
	struct device_dma_parameters	dma_parms;
	struct sdma_channel		channel[MAX_DMA_CHANNELS];
	struct sdma_channel_control	*channel_control;
	void __iomem			*regs;
	unsigned int			version;
	unsigned int			num_events;
	struct sdma_context_data	*context;
	dma_addr_t			context_phys;
	struct dma_device		dma_device;
	struct clk			*clk;
	struct sdma_script_start_addrs	*script_addrs;
};

#define SDMA_H_CONFIG_DSPDMA	(1 << 12) /* indicates if the DSPDMA is used */
#define SDMA_H_CONFIG_RTD_PINS	(1 << 11) /* indicates if Real-Time Debug pins are enabled */
#define SDMA_H_CONFIG_ACR	(1 << 4)  /* indicates if AHB freq /core freq = 2 or 1 */
#define SDMA_H_CONFIG_CSM	(3)       /* indicates which context switch mode is selected*/

static inline u32 chnenbl_ofs(struct sdma_engine *sdma, unsigned int event)
{
	u32 chnenbl0 = (sdma->version == 2 ? SDMA_CHNENBL0_V2 : SDMA_CHNENBL0_V1);

	return chnenbl0 + event * 4;
}

static int sdma_config_ownership(struct sdma_channel *sdmac,
		bool event_override, bool mcu_override, bool dsp_override)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	u32 evt, mcu, dsp;

	if (event_override && mcu_override && dsp_override)
		return -EINVAL;

	evt = __raw_readl(sdma->regs + SDMA_H_EVTOVR);
	mcu = __raw_readl(sdma->regs + SDMA_H_HOSTOVR);
	dsp = __raw_readl(sdma->regs + SDMA_H_DSPOVR);

	if (dsp_override)
		dsp &= ~(1 << channel);
	else
		dsp |= (1 << channel);

	if (event_override)
		evt &= ~(1 << channel);
	else
		evt |= (1 << channel);

	if (mcu_override)
		mcu &= ~(1 << channel);
	else
		mcu |= (1 << channel);

	__raw_writel(evt, sdma->regs + SDMA_H_EVTOVR);
	__raw_writel(mcu, sdma->regs + SDMA_H_HOSTOVR);
	__raw_writel(dsp, sdma->regs + SDMA_H_DSPOVR);

	return 0;
}

/*
 * sdma_run_channel - run a channel and wait till it's done
 */
static int sdma_run_channel(struct sdma_channel *sdmac)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	int ret;

	init_completion(&sdmac->done);

	__raw_writel(1 << channel, sdma->regs + SDMA_H_START);

	ret = wait_for_completion_timeout(&sdmac->done, HZ);

	return ret ? 0 : -ETIMEDOUT;
}

static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
		u32 address)
{
	struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
	void *buf_virt;
	dma_addr_t buf_phys;
	int ret;

	buf_virt = dma_alloc_coherent(NULL,
			size,
			&buf_phys, GFP_KERNEL);
	if (!buf_virt)
		return -ENOMEM;

	bd0->mode.command = C0_SETPM;
	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
	bd0->mode.count = size / 2;
	bd0->buffer_addr = buf_phys;
	bd0->ext_buffer_addr = address;

	memcpy(buf_virt, buf, size);

	ret = sdma_run_channel(&sdma->channel[0]);

	dma_free_coherent(NULL, size, buf_virt, buf_phys);

	return ret;
}

static void sdma_event_enable(struct sdma_channel *sdmac, unsigned int event)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	u32 val;
	u32 chnenbl = chnenbl_ofs(sdma, event);

	val = __raw_readl(sdma->regs + chnenbl);
	val |= (1 << channel);
	__raw_writel(val, sdma->regs + chnenbl);
}

static void sdma_event_disable(struct sdma_channel *sdmac, unsigned int event)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	u32 chnenbl = chnenbl_ofs(sdma, event);
	u32 val;

	val = __raw_readl(sdma->regs + chnenbl);
	val &= ~(1 << channel);
	__raw_writel(val, sdma->regs + chnenbl);
}

static void sdma_handle_channel_loop(struct sdma_channel *sdmac)
{
	struct sdma_buffer_descriptor *bd;

	/*
	 * loop mode. Iterate over descriptors, re-setup them and
	 * call callback function.
	 */
	while (1) {
		bd = &sdmac->bd[sdmac->buf_tail];

		if (bd->mode.status & BD_DONE)
			break;

		if (bd->mode.status & BD_RROR)
			sdmac->status = DMA_ERROR;
		else
			sdmac->status = DMA_SUCCESS;

		bd->mode.status |= BD_DONE;
		sdmac->buf_tail++;
		sdmac->buf_tail %= sdmac->num_bd;

		if (sdmac->desc.callback)
			sdmac->desc.callback(sdmac->desc.callback_param);
	}
}

static void mxc_sdma_handle_channel_normal(struct sdma_channel *sdmac)
{
	struct sdma_buffer_descriptor *bd;
	int i, error = 0;

	/*
	 * non loop mode. Iterate over all descriptors, collect
	 * errors and call callback function
	 */
	for (i = 0; i < sdmac->num_bd; i++) {
		bd = &sdmac->bd[i];

		 if (bd->mode.status & (BD_DONE | BD_RROR))
			error = -EIO;
	}

	if (error)
		sdmac->status = DMA_ERROR;
	else
		sdmac->status = DMA_SUCCESS;

	if (sdmac->desc.callback)
		sdmac->desc.callback(sdmac->desc.callback_param);
	sdmac->last_completed = sdmac->desc.cookie;
}

static void mxc_sdma_handle_channel(struct sdma_channel *sdmac)
{
	complete(&sdmac->done);

	/* not interested in channel 0 interrupts */
	if (sdmac->channel == 0)
		return;

	if (sdmac->flags & IMX_DMA_SG_LOOP)
		sdma_handle_channel_loop(sdmac);
	else
		mxc_sdma_handle_channel_normal(sdmac);
}

static irqreturn_t sdma_int_handler(int irq, void *dev_id)
{
	struct sdma_engine *sdma = dev_id;
	u32 stat;

	stat = __raw_readl(sdma->regs + SDMA_H_INTR);
	__raw_writel(stat, sdma->regs + SDMA_H_INTR);

	while (stat) {
		int channel = fls(stat) - 1;
		struct sdma_channel *sdmac = &sdma->channel[channel];

		mxc_sdma_handle_channel(sdmac);

		stat &= ~(1 << channel);
	}

	return IRQ_HANDLED;
}

/*
 * sets the pc of SDMA script according to the peripheral type
 */
static void sdma_get_pc(struct sdma_channel *sdmac,
		enum sdma_peripheral_type peripheral_type)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int per_2_emi = 0, emi_2_per = 0;
	/*
	 * These are needed once we start to support transfers between
	 * two peripherals or memory-to-memory transfers
	 */
	int per_2_per = 0, emi_2_emi = 0;

	sdmac->pc_from_device = 0;
	sdmac->pc_to_device = 0;

	switch (peripheral_type) {
	case IMX_DMATYPE_MEMORY:
		emi_2_emi = sdma->script_addrs->ap_2_ap_addr;
		break;
	case IMX_DMATYPE_DSP:
		emi_2_per = sdma->script_addrs->bp_2_ap_addr;
		per_2_emi = sdma->script_addrs->ap_2_bp_addr;
		break;
	case IMX_DMATYPE_FIRI:
		per_2_emi = sdma->script_addrs->firi_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_firi_addr;
		break;
	case IMX_DMATYPE_UART:
		per_2_emi = sdma->script_addrs->uart_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_app_addr;
		break;
	case IMX_DMATYPE_UART_SP:
		per_2_emi = sdma->script_addrs->uartsh_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_shp_addr;
		break;
	case IMX_DMATYPE_ATA:
		per_2_emi = sdma->script_addrs->ata_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_ata_addr;
		break;
	case IMX_DMATYPE_CSPI:
	case IMX_DMATYPE_EXT:
	case IMX_DMATYPE_SSI:
		per_2_emi = sdma->script_addrs->app_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_app_addr;
		break;
	case IMX_DMATYPE_SSI_SP:
	case IMX_DMATYPE_MMC:
	case IMX_DMATYPE_SDHC:
	case IMX_DMATYPE_CSPI_SP:
	case IMX_DMATYPE_ESAI:
	case IMX_DMATYPE_MSHC_SP:
		per_2_emi = sdma->script_addrs->shp_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_shp_addr;
		break;
	case IMX_DMATYPE_ASRC:
		per_2_emi = sdma->script_addrs->asrc_2_mcu_addr;
		emi_2_per = sdma->script_addrs->asrc_2_mcu_addr;
		per_2_per = sdma->script_addrs->per_2_per_addr;
		break;
	case IMX_DMATYPE_MSHC:
		per_2_emi = sdma->script_addrs->mshc_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_mshc_addr;
		break;
	case IMX_DMATYPE_CCM:
		per_2_emi = sdma->script_addrs->dptc_dvfs_addr;
		break;
	case IMX_DMATYPE_SPDIF:
		per_2_emi = sdma->script_addrs->spdif_2_mcu_addr;
		emi_2_per = sdma->script_addrs->mcu_2_spdif_addr;
		break;
	case IMX_DMATYPE_IPU_MEMORY:
		emi_2_per = sdma->script_addrs->ext_mem_2_ipu_addr;
		break;
	default:
		break;
	}

	sdmac->pc_from_device = per_2_emi;
	sdmac->pc_to_device = emi_2_per;
}

static int sdma_load_context(struct sdma_channel *sdmac)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	int load_address;
	struct sdma_context_data *context = sdma->context;
	struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
	int ret;

	if (sdmac->direction == DMA_FROM_DEVICE) {
		load_address = sdmac->pc_from_device;
	} else {
		load_address = sdmac->pc_to_device;
	}

	if (load_address < 0)
		return load_address;

	dev_dbg(sdma->dev, "load_address = %d\n", load_address);
	dev_dbg(sdma->dev, "wml = 0x%08x\n", sdmac->watermark_level);
	dev_dbg(sdma->dev, "shp_addr = 0x%08x\n", sdmac->shp_addr);
	dev_dbg(sdma->dev, "per_addr = 0x%08x\n", sdmac->per_addr);
	dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", sdmac->event_mask0);
	dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", sdmac->event_mask1);

	memset(context, 0, sizeof(*context));
	context->channel_state.pc = load_address;

	/* Send by context the event mask,base address for peripheral
	 * and watermark level
	 */
	context->gReg[0] = sdmac->event_mask1;
	context->gReg[1] = sdmac->event_mask0;
	context->gReg[2] = sdmac->per_addr;
	context->gReg[6] = sdmac->shp_addr;
	context->gReg[7] = sdmac->watermark_level;

	bd0->mode.command = C0_SETDM;
	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
	bd0->mode.count = sizeof(*context) / 4;
	bd0->buffer_addr = sdma->context_phys;
	bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * channel;

	ret = sdma_run_channel(&sdma->channel[0]);

	return ret;
}

static void sdma_disable_channel(struct sdma_channel *sdmac)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;

	__raw_writel(1 << channel, sdma->regs + SDMA_H_STATSTOP);
	sdmac->status = DMA_ERROR;
}

static int sdma_config_channel(struct sdma_channel *sdmac)
{
	int ret;

	sdma_disable_channel(sdmac);

	sdmac->event_mask0 = 0;
	sdmac->event_mask1 = 0;
	sdmac->shp_addr = 0;
	sdmac->per_addr = 0;

	if (sdmac->event_id0) {
		if (sdmac->event_id0 > 32)
			return -EINVAL;
		sdma_event_enable(sdmac, sdmac->event_id0);
	}

	switch (sdmac->peripheral_type) {
	case IMX_DMATYPE_DSP:
		sdma_config_ownership(sdmac, false, true, true);
		break;
	case IMX_DMATYPE_MEMORY:
		sdma_config_ownership(sdmac, false, true, false);
		break;
	default:
		sdma_config_ownership(sdmac, true, true, false);
		break;
	}

	sdma_get_pc(sdmac, sdmac->peripheral_type);

	if ((sdmac->peripheral_type != IMX_DMATYPE_MEMORY) &&
			(sdmac->peripheral_type != IMX_DMATYPE_DSP)) {
		/* Handle multiple event channels differently */
		if (sdmac->event_id1) {
			sdmac->event_mask1 = 1 << (sdmac->event_id1 % 32);
			if (sdmac->event_id1 > 31)
				sdmac->watermark_level |= 1 << 31;
			sdmac->event_mask0 = 1 << (sdmac->event_id0 % 32);
			if (sdmac->event_id0 > 31)
				sdmac->watermark_level |= 1 << 30;
		} else {
			sdmac->event_mask0 = 1 << sdmac->event_id0;
			sdmac->event_mask1 = 1 << (sdmac->event_id0 - 32);
		}
		/* Watermark Level */
		sdmac->watermark_level |= sdmac->watermark_level;
		/* Address */
		sdmac->shp_addr = sdmac->per_address;
	} else {
		sdmac->watermark_level = 0; /* FIXME: M3_BASE_ADDRESS */
	}

	ret = sdma_load_context(sdmac);

	return ret;
}

static int sdma_set_channel_priority(struct sdma_channel *sdmac,
		unsigned int priority)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;

	if (priority < MXC_SDMA_MIN_PRIORITY
	    || priority > MXC_SDMA_MAX_PRIORITY) {
		return -EINVAL;
	}

	__raw_writel(priority, sdma->regs + SDMA_CHNPRI_0 + 4 * channel);

	return 0;
}

static int sdma_request_channel(struct sdma_channel *sdmac)
{
	struct sdma_engine *sdma = sdmac->sdma;
	int channel = sdmac->channel;
	int ret = -EBUSY;

	sdmac->bd = dma_alloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys, GFP_KERNEL);
	if (!sdmac->bd) {
		ret = -ENOMEM;
		goto out;
	}

	memset(sdmac->bd, 0, PAGE_SIZE);

	sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
	sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;

	clk_enable(sdma->clk);

	sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);

	init_completion(&sdmac->done);

	sdmac->buf_tail = 0;

	return 0;
out:

	return ret;
}

static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
{
	__raw_writel(1 << channel, sdma->regs + SDMA_H_START);
}

static dma_cookie_t sdma_assign_cookie(struct sdma_channel *sdma)
{
	dma_cookie_t cookie = sdma->chan.cookie;

	if (++cookie < 0)
		cookie = 1;

	sdma->chan.cookie = cookie;
	sdma->desc.cookie = cookie;

	return cookie;
}

static struct sdma_channel *to_sdma_chan(struct dma_chan *chan)
{
	return container_of(chan, struct sdma_channel, chan);
}

static dma_cookie_t sdma_tx_submit(struct dma_async_tx_descriptor *tx)
{
	struct sdma_channel *sdmac = to_sdma_chan(tx->chan);
	struct sdma_engine *sdma = sdmac->sdma;
	dma_cookie_t cookie;

	spin_lock_irq(&sdmac->lock);

	cookie = sdma_assign_cookie(sdmac);

	sdma_enable_channel(sdma, sdmac->channel);

	spin_unlock_irq(&sdmac->lock);

	return cookie;
}

static int sdma_alloc_chan_resources(struct dma_chan *chan)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	struct imx_dma_data *data = chan->private;
	int prio, ret;

	if (!data)
		return -EINVAL;

	switch (data->priority) {
	case DMA_PRIO_HIGH:
		prio = 3;
		break;
	case DMA_PRIO_MEDIUM:
		prio = 2;
		break;
	case DMA_PRIO_LOW:
	default:
		prio = 1;
		break;
	}

	sdmac->peripheral_type = data->peripheral_type;
	sdmac->event_id0 = data->dma_request;
	ret = sdma_set_channel_priority(sdmac, prio);
	if (ret)
		return ret;

	ret = sdma_request_channel(sdmac);
	if (ret)
		return ret;

	dma_async_tx_descriptor_init(&sdmac->desc, chan);
	sdmac->desc.tx_submit = sdma_tx_submit;
	/* txd.flags will be overwritten in prep funcs */
	sdmac->desc.flags = DMA_CTRL_ACK;

	return 0;
}

static void sdma_free_chan_resources(struct dma_chan *chan)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	struct sdma_engine *sdma = sdmac->sdma;

	sdma_disable_channel(sdmac);

	if (sdmac->event_id0)
		sdma_event_disable(sdmac, sdmac->event_id0);
	if (sdmac->event_id1)
		sdma_event_disable(sdmac, sdmac->event_id1);

	sdmac->event_id0 = 0;
	sdmac->event_id1 = 0;

	sdma_set_channel_priority(sdmac, 0);

	dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);

	clk_disable(sdma->clk);
}

static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
		struct dma_chan *chan, struct scatterlist *sgl,
		unsigned int sg_len, enum dma_data_direction direction,
		unsigned long flags)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	struct sdma_engine *sdma = sdmac->sdma;
	int ret, i, count;
	int channel = sdmac->channel;
	struct scatterlist *sg;

	if (sdmac->status == DMA_IN_PROGRESS)
		return NULL;
	sdmac->status = DMA_IN_PROGRESS;

	sdmac->flags = 0;

	dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
			sg_len, channel);

	sdmac->direction = direction;
	ret = sdma_load_context(sdmac);
	if (ret)
		goto err_out;

	if (sg_len > NUM_BD) {
		dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
				channel, sg_len, NUM_BD);
		ret = -EINVAL;
		goto err_out;
	}

	for_each_sg(sgl, sg, sg_len, i) {
		struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
		int param;

		bd->buffer_addr = sg->dma_address;

		count = sg->length;

		if (count > 0xffff) {
			dev_err(sdma->dev, "SDMA channel %d: maximum bytes for sg entry exceeded: %d > %d\n",
					channel, count, 0xffff);
			ret = -EINVAL;
			goto err_out;
		}

		bd->mode.count = count;

		if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
			ret =  -EINVAL;
			goto err_out;
		}

		switch (sdmac->word_size) {
		case DMA_SLAVE_BUSWIDTH_4_BYTES:
			bd->mode.command = 0;
			if (count & 3 || sg->dma_address & 3)
				return NULL;
			break;
		case DMA_SLAVE_BUSWIDTH_2_BYTES:
			bd->mode.command = 2;
			if (count & 1 || sg->dma_address & 1)
				return NULL;
			break;
		case DMA_SLAVE_BUSWIDTH_1_BYTE:
			bd->mode.command = 1;
			break;
		default:
			return NULL;
		}

		param = BD_DONE | BD_EXTD | BD_CONT;

		if (sdmac->flags & IMX_DMA_SG_LOOP) {
			param |= BD_INTR;
			if (i + 1 == sg_len)
				param |= BD_WRAP;
		}

		if (i + 1 == sg_len)
			param |= BD_INTR;

		dev_dbg(sdma->dev, "entry %d: count: %d dma: 0x%08x %s%s\n",
				i, count, sg->dma_address,
				param & BD_WRAP ? "wrap" : "",
				param & BD_INTR ? " intr" : "");

		bd->mode.status = param;
	}

	sdmac->num_bd = sg_len;
	sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;

	return &sdmac->desc;
err_out:
	return NULL;
}

static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
		size_t period_len, enum dma_data_direction direction)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	struct sdma_engine *sdma = sdmac->sdma;
	int num_periods = buf_len / period_len;
	int channel = sdmac->channel;
	int ret, i = 0, buf = 0;

	dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);

	if (sdmac->status == DMA_IN_PROGRESS)
		return NULL;

	sdmac->status = DMA_IN_PROGRESS;

	sdmac->flags |= IMX_DMA_SG_LOOP;
	sdmac->direction = direction;
	ret = sdma_load_context(sdmac);
	if (ret)
		goto err_out;

	if (num_periods > NUM_BD) {
		dev_err(sdma->dev, "SDMA channel %d: maximum number of sg exceeded: %d > %d\n",
				channel, num_periods, NUM_BD);
		goto err_out;
	}

	if (period_len > 0xffff) {
		dev_err(sdma->dev, "SDMA channel %d: maximum period size exceeded: %d > %d\n",
				channel, period_len, 0xffff);
		goto err_out;
	}

	while (buf < buf_len) {
		struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
		int param;

		bd->buffer_addr = dma_addr;

		bd->mode.count = period_len;

		if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES)
			goto err_out;
		if (sdmac->word_size == DMA_SLAVE_BUSWIDTH_4_BYTES)
			bd->mode.command = 0;
		else
			bd->mode.command = sdmac->word_size;

		param = BD_DONE | BD_EXTD | BD_CONT | BD_INTR;
		if (i + 1 == num_periods)
			param |= BD_WRAP;

		dev_dbg(sdma->dev, "entry %d: count: %d dma: 0x%08x %s%s\n",
				i, period_len, dma_addr,
				param & BD_WRAP ? "wrap" : "",
				param & BD_INTR ? " intr" : "");

		bd->mode.status = param;

		dma_addr += period_len;
		buf += period_len;

		i++;
	}

	sdmac->num_bd = num_periods;
	sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;

	return &sdmac->desc;
err_out:
	sdmac->status = DMA_ERROR;
	return NULL;
}

static int sdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
		unsigned long arg)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	struct dma_slave_config *dmaengine_cfg = (void *)arg;

	switch (cmd) {
	case DMA_TERMINATE_ALL:
		sdma_disable_channel(sdmac);
		return 0;
	case DMA_SLAVE_CONFIG:
		if (dmaengine_cfg->direction == DMA_FROM_DEVICE) {
			sdmac->per_address = dmaengine_cfg->src_addr;
			sdmac->watermark_level = dmaengine_cfg->src_maxburst;
			sdmac->word_size = dmaengine_cfg->src_addr_width;
		} else {
			sdmac->per_address = dmaengine_cfg->dst_addr;
			sdmac->watermark_level = dmaengine_cfg->dst_maxburst;
			sdmac->word_size = dmaengine_cfg->dst_addr_width;
		}
		return sdma_config_channel(sdmac);
	default:
		return -ENOSYS;
	}

	return -EINVAL;
}

static enum dma_status sdma_tx_status(struct dma_chan *chan,
					    dma_cookie_t cookie,
					    struct dma_tx_state *txstate)
{
	struct sdma_channel *sdmac = to_sdma_chan(chan);
	dma_cookie_t last_used;
	enum dma_status ret;

	last_used = chan->cookie;

	ret = dma_async_is_complete(cookie, sdmac->last_completed, last_used);
	dma_set_tx_state(txstate, sdmac->last_completed, last_used, 0);

	return ret;
}

static void sdma_issue_pending(struct dma_chan *chan)
{
	/*
	 * Nothing to do. We only have a single descriptor
	 */
}

#define SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1	34

static void sdma_add_scripts(struct sdma_engine *sdma,
		const struct sdma_script_start_addrs *addr)
{
	s32 *addr_arr = (u32 *)addr;
	s32 *saddr_arr = (u32 *)sdma->script_addrs;
	int i;

	for (i = 0; i < SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1; i++)
		if (addr_arr[i] > 0)
			saddr_arr[i] = addr_arr[i];
}

static int __init sdma_get_firmware(struct sdma_engine *sdma,
		const char *cpu_name, int to_version)
{
	const struct firmware *fw;
	char *fwname;
	const struct sdma_firmware_header *header;
	int ret;
	const struct sdma_script_start_addrs *addr;
	unsigned short *ram_code;

	fwname = kasprintf(GFP_KERNEL, "sdma-%s-to%d.bin", cpu_name, to_version);
	if (!fwname)
		return -ENOMEM;

	ret = request_firmware(&fw, fwname, sdma->dev);
	if (ret) {
		kfree(fwname);
		return ret;
	}
	kfree(fwname);

	if (fw->size < sizeof(*header))
		goto err_firmware;

	header = (struct sdma_firmware_header *)fw->data;

	if (header->magic != SDMA_FIRMWARE_MAGIC)
		goto err_firmware;
	if (header->ram_code_start + header->ram_code_size > fw->size)
		goto err_firmware;

	addr = (void *)header + header->script_addrs_start;
	ram_code = (void *)header + header->ram_code_start;

	clk_enable(sdma->clk);
	/* download the RAM image for SDMA */
	sdma_load_script(sdma, ram_code,
			header->ram_code_size,
			sdma->script_addrs->ram_code_start_addr);
	clk_disable(sdma->clk);

	sdma_add_scripts(sdma, addr);

	dev_info(sdma->dev, "loaded firmware %d.%d\n",
			header->version_major,
			header->version_minor);

err_firmware:
	release_firmware(fw);

	return ret;
}

static int __init sdma_init(struct sdma_engine *sdma)
{
	int i, ret;
	dma_addr_t ccb_phys;

	switch (sdma->version) {
	case 1:
		sdma->num_events = 32;
		break;
	case 2:
		sdma->num_events = 48;
		break;
	default:
		dev_err(sdma->dev, "Unknown version %d. aborting\n", sdma->version);
		return -ENODEV;
	}

	clk_enable(sdma->clk);

	/* Be sure SDMA has not started yet */
	__raw_writel(0, sdma->regs + SDMA_H_C0PTR);

	sdma->channel_control = dma_alloc_coherent(NULL,
			MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control) +
			sizeof(struct sdma_context_data),
			&ccb_phys, GFP_KERNEL);

	if (!sdma->channel_control) {
		ret = -ENOMEM;
		goto err_dma_alloc;
	}

	sdma->context = (void *)sdma->channel_control +
		MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control);
	sdma->context_phys = ccb_phys +
		MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control);

	/* Zero-out the CCB structures array just allocated */
	memset(sdma->channel_control, 0,
			MAX_DMA_CHANNELS * sizeof (struct sdma_channel_control));

	/* disable all channels */
	for (i = 0; i < sdma->num_events; i++)
		__raw_writel(0, sdma->regs + chnenbl_ofs(sdma, i));

	/* All channels have priority 0 */
	for (i = 0; i < MAX_DMA_CHANNELS; i++)
		__raw_writel(0, sdma->regs + SDMA_CHNPRI_0 + i * 4);

	ret = sdma_request_channel(&sdma->channel[0]);
	if (ret)
		goto err_dma_alloc;

	sdma_config_ownership(&sdma->channel[0], false, true, false);

	/* Set Command Channel (Channel Zero) */
	__raw_writel(0x4050, sdma->regs + SDMA_CHN0ADDR);

	/* Set bits of CONFIG register but with static context switching */
	/* FIXME: Check whether to set ACR bit depending on clock ratios */
	__raw_writel(0, sdma->regs + SDMA_H_CONFIG);

	__raw_writel(ccb_phys, sdma->regs + SDMA_H_C0PTR);

	/* Set bits of CONFIG register with given context switching mode */
	__raw_writel(SDMA_H_CONFIG_CSM, sdma->regs + SDMA_H_CONFIG);

	/* Initializes channel's priorities */
	sdma_set_channel_priority(&sdma->channel[0], 7);

	clk_disable(sdma->clk);

	return 0;

err_dma_alloc:
	clk_disable(sdma->clk);
	dev_err(sdma->dev, "initialisation failed with %d\n", ret);
	return ret;
}

static int __init sdma_probe(struct platform_device *pdev)
{
	int ret;
	int irq;
	struct resource *iores;
	struct sdma_platform_data *pdata = pdev->dev.platform_data;
	int i;
	struct sdma_engine *sdma;

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

	sdma->dev = &pdev->dev;

	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
	if (!iores || irq < 0 || !pdata) {
		ret = -EINVAL;
		goto err_irq;
	}

	if (!request_mem_region(iores->start, resource_size(iores), pdev->name)) {
		ret = -EBUSY;
		goto err_request_region;
	}

	sdma->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(sdma->clk)) {
		ret = PTR_ERR(sdma->clk);
		goto err_clk;
	}

	sdma->regs = ioremap(iores->start, resource_size(iores));
	if (!sdma->regs) {
		ret = -ENOMEM;
		goto err_ioremap;
	}

	ret = request_irq(irq, sdma_int_handler, 0, "sdma", sdma);
	if (ret)
		goto err_request_irq;

	sdma->script_addrs = kzalloc(sizeof(*sdma->script_addrs), GFP_KERNEL);
	if (!sdma->script_addrs)
		goto err_alloc;

	sdma->version = pdata->sdma_version;

	dma_cap_set(DMA_SLAVE, sdma->dma_device.cap_mask);
	dma_cap_set(DMA_CYCLIC, sdma->dma_device.cap_mask);

	INIT_LIST_HEAD(&sdma->dma_device.channels);
	/* Initialize channel parameters */
	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
		struct sdma_channel *sdmac = &sdma->channel[i];

		sdmac->sdma = sdma;
		spin_lock_init(&sdmac->lock);

		sdmac->chan.device = &sdma->dma_device;
		sdmac->channel = i;

		/*
		 * Add the channel to the DMAC list. Do not add channel 0 though
		 * because we need it internally in the SDMA driver. This also means
		 * that channel 0 in dmaengine counting matches sdma channel 1.
		 */
		if (i)
			list_add_tail(&sdmac->chan.device_node,
					&sdma->dma_device.channels);
	}

	ret = sdma_init(sdma);
	if (ret)
		goto err_init;

	if (pdata->script_addrs)
		sdma_add_scripts(sdma, pdata->script_addrs);

	sdma_get_firmware(sdma, pdata->cpu_name, pdata->to_version);

	sdma->dma_device.dev = &pdev->dev;

	sdma->dma_device.device_alloc_chan_resources = sdma_alloc_chan_resources;
	sdma->dma_device.device_free_chan_resources = sdma_free_chan_resources;
	sdma->dma_device.device_tx_status = sdma_tx_status;
	sdma->dma_device.device_prep_slave_sg = sdma_prep_slave_sg;
	sdma->dma_device.device_prep_dma_cyclic = sdma_prep_dma_cyclic;
	sdma->dma_device.device_control = sdma_control;
	sdma->dma_device.device_issue_pending = sdma_issue_pending;
	sdma->dma_device.dev->dma_parms = &sdma->dma_parms;
	dma_set_max_seg_size(sdma->dma_device.dev, 65535);

	ret = dma_async_device_register(&sdma->dma_device);
	if (ret) {
		dev_err(&pdev->dev, "unable to register\n");
		goto err_init;
	}

	dev_info(sdma->dev, "initialized\n");

	return 0;

err_init:
	kfree(sdma->script_addrs);
err_alloc:
	free_irq(irq, sdma);
err_request_irq:
	iounmap(sdma->regs);
err_ioremap:
	clk_put(sdma->clk);
err_clk:
	release_mem_region(iores->start, resource_size(iores));
err_request_region:
err_irq:
	kfree(sdma);
	return 0;
}

static int __exit sdma_remove(struct platform_device *pdev)
{
	return -EBUSY;
}

static struct platform_driver sdma_driver = {
	.driver		= {
		.name	= "imx-sdma",
	},
	.remove		= __exit_p(sdma_remove),
};

static int __init sdma_module_init(void)
{
	return platform_driver_probe(&sdma_driver, sdma_probe);
}
module_init(sdma_module_init);

MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
MODULE_DESCRIPTION("i.MX SDMA driver");
MODULE_LICENSE("GPL");