Free Electrons

Embedded Linux Experts

  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
/*
 * OMAP2+ DMA driver
 *
 * Copyright (C) 2003 - 2008 Nokia Corporation
 * Author: Juha Yrjölä <juha.yrjola@nokia.com>
 * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
 * Graphics DMA and LCD DMA graphics tranformations
 * by Imre Deak <imre.deak@nokia.com>
 * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
 * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
 *
 * Copyright (C) 2009 Texas Instruments
 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 *
 * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
 * Converted DMA library into platform driver
 *	- G, Manjunath Kondaiah <manjugk@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/of.h>
#include <linux/omap-dma.h>

#include "soc.h"
#include "omap_hwmod.h"
#include "omap_device.h"

static enum omap_reg_offsets dma_common_ch_end;

static const struct omap_dma_reg reg_map[] = {
	[REVISION]	= { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
	[GCR]		= { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
	[IRQSTATUS_L0]	= { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
	[IRQSTATUS_L1]	= { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
	[IRQSTATUS_L2]	= { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
	[IRQSTATUS_L3]	= { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
	[IRQENABLE_L0]	= { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
	[IRQENABLE_L1]	= { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
	[IRQENABLE_L2]	= { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
	[IRQENABLE_L3]	= { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
	[SYSSTATUS]	= { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
	[OCP_SYSCONFIG]	= { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
	[CAPS_0]	= { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
	[CAPS_2]	= { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
	[CAPS_3]	= { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
	[CAPS_4]	= { 0x0074, 0x00, OMAP_DMA_REG_32BIT },

	/* Common register offsets */
	[CCR]		= { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
	[CLNK_CTRL]	= { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
	[CICR]		= { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
	[CSR]		= { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
	[CSDP]		= { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
	[CEN]		= { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
	[CFN]		= { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
	[CSEI]		= { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
	[CSFI]		= { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
	[CDEI]		= { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
	[CDFI]		= { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
	[CSAC]		= { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
	[CDAC]		= { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },

	/* Channel specific register offsets */
	[CSSA]		= { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
	[CDSA]		= { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
	[CCEN]		= { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
	[CCFN]		= { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
	[COLOR]		= { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },

	/* OMAP4 specific registers */
	[CDP]		= { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
	[CNDP]		= { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
	[CCDN]		= { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
};

static void __iomem *dma_base;
static inline void dma_write(u32 val, int reg, int lch)
{
	void __iomem *addr = dma_base;

	addr += reg_map[reg].offset;
	addr += reg_map[reg].stride * lch;

	writel_relaxed(val, addr);
}

static inline u32 dma_read(int reg, int lch)
{
	void __iomem *addr = dma_base;

	addr += reg_map[reg].offset;
	addr += reg_map[reg].stride * lch;

	return readl_relaxed(addr);
}

static void omap2_clear_dma(int lch)
{
	int i;

	for (i = CSDP; i <= dma_common_ch_end; i += 1)
		dma_write(0, i, lch);
}

static void omap2_show_dma_caps(void)
{
	u8 revision = dma_read(REVISION, 0) & 0xff;
	printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
				revision >> 4, revision & 0xf);
}

static unsigned configure_dma_errata(void)
{
	unsigned errata = 0;

	/*
	 * Errata applicable for OMAP2430ES1.0 and all omap2420
	 *
	 * I.
	 * Erratum ID: Not Available
	 * Inter Frame DMA buffering issue DMA will wrongly
	 * buffer elements if packing and bursting is enabled. This might
	 * result in data gets stalled in FIFO at the end of the block.
	 * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
	 * guarantee no data will stay in the DMA FIFO in case inter frame
	 * buffering occurs
	 *
	 * II.
	 * Erratum ID: Not Available
	 * DMA may hang when several channels are used in parallel
	 * In the following configuration, DMA channel hanging can occur:
	 * a. Channel i, hardware synchronized, is enabled
	 * b. Another channel (Channel x), software synchronized, is enabled.
	 * c. Channel i is disabled before end of transfer
	 * d. Channel i is reenabled.
	 * e. Steps 1 to 4 are repeated a certain number of times.
	 * f. A third channel (Channel y), software synchronized, is enabled.
	 * Channel x and Channel y may hang immediately after step 'f'.
	 * Workaround:
	 * For any channel used - make sure NextLCH_ID is set to the value j.
	 */
	if (cpu_is_omap2420() || (cpu_is_omap2430() &&
				(omap_type() == OMAP2430_REV_ES1_0))) {

		SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
		SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
	}

	/*
	 * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
	 * after a transaction error.
	 * Workaround: SW should explicitely disable the channel.
	 */
	if (cpu_class_is_omap2())
		SET_DMA_ERRATA(DMA_ERRATA_i378);

	/*
	 * Erratum ID: i541: sDMA FIFO draining does not finish
	 * If sDMA channel is disabled on the fly, sDMA enters standby even
	 * through FIFO Drain is still in progress
	 * Workaround: Put sDMA in NoStandby more before a logical channel is
	 * disabled, then put it back to SmartStandby right after the channel
	 * finishes FIFO draining.
	 */
	if (cpu_is_omap34xx())
		SET_DMA_ERRATA(DMA_ERRATA_i541);

	/*
	 * Erratum ID: i88 : Special programming model needed to disable DMA
	 * before end of block.
	 * Workaround: software must ensure that the DMA is configured in No
	 * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
	 */
	if (omap_type() == OMAP3430_REV_ES1_0)
		SET_DMA_ERRATA(DMA_ERRATA_i88);

	/*
	 * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
	 * read before the DMA controller finished disabling the channel.
	 */
	SET_DMA_ERRATA(DMA_ERRATA_3_3);

	/*
	 * Erratum ID: Not Available
	 * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
	 * after secure sram context save and restore.
	 * Work around: Hence we need to manually clear those IRQs to avoid
	 * spurious interrupts. This affects only secure devices.
	 */
	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
		SET_DMA_ERRATA(DMA_ROMCODE_BUG);

	return errata;
}

static const struct dma_slave_map omap24xx_sdma_map[] = {
	{ "omap-gpmc", "rxtx", SDMA_FILTER_PARAM(4) },
	{ "omap-aes", "tx", SDMA_FILTER_PARAM(9) },
	{ "omap-aes", "rx", SDMA_FILTER_PARAM(10) },
	{ "omap-sham", "rx", SDMA_FILTER_PARAM(13) },
	{ "omap2_mcspi.2", "tx0", SDMA_FILTER_PARAM(15) },
	{ "omap2_mcspi.2", "rx0", SDMA_FILTER_PARAM(16) },
	{ "omap-mcbsp.3", "tx", SDMA_FILTER_PARAM(17) },
	{ "omap-mcbsp.3", "rx", SDMA_FILTER_PARAM(18) },
	{ "omap-mcbsp.4", "tx", SDMA_FILTER_PARAM(19) },
	{ "omap-mcbsp.4", "rx", SDMA_FILTER_PARAM(20) },
	{ "omap-mcbsp.5", "tx", SDMA_FILTER_PARAM(21) },
	{ "omap-mcbsp.5", "rx", SDMA_FILTER_PARAM(22) },
	{ "omap2_mcspi.2", "tx1", SDMA_FILTER_PARAM(23) },
	{ "omap2_mcspi.2", "rx1", SDMA_FILTER_PARAM(24) },
	{ "omap_i2c.1", "tx", SDMA_FILTER_PARAM(27) },
	{ "omap_i2c.1", "rx", SDMA_FILTER_PARAM(28) },
	{ "omap_i2c.2", "tx", SDMA_FILTER_PARAM(29) },
	{ "omap_i2c.2", "rx", SDMA_FILTER_PARAM(30) },
	{ "omap-mcbsp.1", "tx", SDMA_FILTER_PARAM(31) },
	{ "omap-mcbsp.1", "rx", SDMA_FILTER_PARAM(32) },
	{ "omap-mcbsp.2", "tx", SDMA_FILTER_PARAM(33) },
	{ "omap-mcbsp.2", "rx", SDMA_FILTER_PARAM(34) },
	{ "omap2_mcspi.0", "tx0", SDMA_FILTER_PARAM(35) },
	{ "omap2_mcspi.0", "rx0", SDMA_FILTER_PARAM(36) },
	{ "omap2_mcspi.0", "tx1", SDMA_FILTER_PARAM(37) },
	{ "omap2_mcspi.0", "rx1", SDMA_FILTER_PARAM(38) },
	{ "omap2_mcspi.0", "tx2", SDMA_FILTER_PARAM(39) },
	{ "omap2_mcspi.0", "rx2", SDMA_FILTER_PARAM(40) },
	{ "omap2_mcspi.0", "tx3", SDMA_FILTER_PARAM(41) },
	{ "omap2_mcspi.0", "rx3", SDMA_FILTER_PARAM(42) },
	{ "omap2_mcspi.1", "tx0", SDMA_FILTER_PARAM(43) },
	{ "omap2_mcspi.1", "rx0", SDMA_FILTER_PARAM(44) },
	{ "omap2_mcspi.1", "tx1", SDMA_FILTER_PARAM(45) },
	{ "omap2_mcspi.1", "rx1", SDMA_FILTER_PARAM(46) },
	{ "omap_hsmmc.1", "tx", SDMA_FILTER_PARAM(47) },
	{ "omap_hsmmc.1", "rx", SDMA_FILTER_PARAM(48) },
	{ "omap_uart.0", "tx", SDMA_FILTER_PARAM(49) },
	{ "omap_uart.0", "rx", SDMA_FILTER_PARAM(50) },
	{ "omap_uart.1", "tx", SDMA_FILTER_PARAM(51) },
	{ "omap_uart.1", "rx", SDMA_FILTER_PARAM(52) },
	{ "omap_uart.2", "tx", SDMA_FILTER_PARAM(53) },
	{ "omap_uart.2", "rx", SDMA_FILTER_PARAM(54) },
	{ "omap_hsmmc.0", "tx", SDMA_FILTER_PARAM(61) },
	{ "omap_hsmmc.0", "rx", SDMA_FILTER_PARAM(62) },

	/* external DMA requests when tusb6010 is used */
	{ "musb-tusb", "dmareq0", SDMA_FILTER_PARAM(2) },
	{ "musb-tusb", "dmareq1", SDMA_FILTER_PARAM(3) },
	{ "musb-tusb", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
	{ "musb-tusb", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
	{ "musb-tusb", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
	{ "musb-tusb", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
};

static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
	/* external DMA requests when tusb6010 is used */
	{ "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
	{ "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
	{ "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
	{ "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
	{ "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
	{ "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
};

static const struct dma_slave_map omap3xxx_sdma_map[] = {
	{ "omap-gpmc", "rxtx", SDMA_FILTER_PARAM(4) },
	{ "omap2_mcspi.2", "tx0", SDMA_FILTER_PARAM(15) },
	{ "omap2_mcspi.2", "rx0", SDMA_FILTER_PARAM(16) },
	{ "omap-mcbsp.3", "tx", SDMA_FILTER_PARAM(17) },
	{ "omap-mcbsp.3", "rx", SDMA_FILTER_PARAM(18) },
	{ "omap-mcbsp.4", "tx", SDMA_FILTER_PARAM(19) },
	{ "omap-mcbsp.4", "rx", SDMA_FILTER_PARAM(20) },
	{ "omap-mcbsp.5", "tx", SDMA_FILTER_PARAM(21) },
	{ "omap-mcbsp.5", "rx", SDMA_FILTER_PARAM(22) },
	{ "omap2_mcspi.2", "tx1", SDMA_FILTER_PARAM(23) },
	{ "omap2_mcspi.2", "rx1", SDMA_FILTER_PARAM(24) },
	{ "omap_i2c.3", "tx", SDMA_FILTER_PARAM(25) },
	{ "omap_i2c.3", "rx", SDMA_FILTER_PARAM(26) },
	{ "omap_i2c.1", "tx", SDMA_FILTER_PARAM(27) },
	{ "omap_i2c.1", "rx", SDMA_FILTER_PARAM(28) },
	{ "omap_i2c.2", "tx", SDMA_FILTER_PARAM(29) },
	{ "omap_i2c.2", "rx", SDMA_FILTER_PARAM(30) },
	{ "omap-mcbsp.1", "tx", SDMA_FILTER_PARAM(31) },
	{ "omap-mcbsp.1", "rx", SDMA_FILTER_PARAM(32) },
	{ "omap-mcbsp.2", "tx", SDMA_FILTER_PARAM(33) },
	{ "omap-mcbsp.2", "rx", SDMA_FILTER_PARAM(34) },
	{ "omap2_mcspi.0", "tx0", SDMA_FILTER_PARAM(35) },
	{ "omap2_mcspi.0", "rx0", SDMA_FILTER_PARAM(36) },
	{ "omap2_mcspi.0", "tx1", SDMA_FILTER_PARAM(37) },
	{ "omap2_mcspi.0", "rx1", SDMA_FILTER_PARAM(38) },
	{ "omap2_mcspi.0", "tx2", SDMA_FILTER_PARAM(39) },
	{ "omap2_mcspi.0", "rx2", SDMA_FILTER_PARAM(40) },
	{ "omap2_mcspi.0", "tx3", SDMA_FILTER_PARAM(41) },
	{ "omap2_mcspi.0", "rx3", SDMA_FILTER_PARAM(42) },
	{ "omap2_mcspi.1", "tx0", SDMA_FILTER_PARAM(43) },
	{ "omap2_mcspi.1", "rx0", SDMA_FILTER_PARAM(44) },
	{ "omap2_mcspi.1", "tx1", SDMA_FILTER_PARAM(45) },
	{ "omap2_mcspi.1", "rx1", SDMA_FILTER_PARAM(46) },
	{ "omap_hsmmc.1", "tx", SDMA_FILTER_PARAM(47) },
	{ "omap_hsmmc.1", "rx", SDMA_FILTER_PARAM(48) },
	{ "omap_uart.0", "tx", SDMA_FILTER_PARAM(49) },
	{ "omap_uart.0", "rx", SDMA_FILTER_PARAM(50) },
	{ "omap_uart.1", "tx", SDMA_FILTER_PARAM(51) },
	{ "omap_uart.1", "rx", SDMA_FILTER_PARAM(52) },
	{ "omap_uart.2", "tx", SDMA_FILTER_PARAM(53) },
	{ "omap_uart.2", "rx", SDMA_FILTER_PARAM(54) },
	{ "omap_hsmmc.0", "tx", SDMA_FILTER_PARAM(61) },
	{ "omap_hsmmc.0", "rx", SDMA_FILTER_PARAM(62) },
	{ "omap-aes", "tx", SDMA_FILTER_PARAM(65) },
	{ "omap-aes", "rx", SDMA_FILTER_PARAM(66) },
	{ "omap-sham", "rx", SDMA_FILTER_PARAM(69) },
	{ "omap2_mcspi.3", "tx0", SDMA_FILTER_PARAM(70) },
	{ "omap2_mcspi.3", "rx0", SDMA_FILTER_PARAM(71) },
	{ "omap_hsmmc.2", "tx", SDMA_FILTER_PARAM(77) },
	{ "omap_hsmmc.2", "rx", SDMA_FILTER_PARAM(78) },
	{ "omap_uart.3", "tx", SDMA_FILTER_PARAM(81) },
	{ "omap_uart.3", "rx", SDMA_FILTER_PARAM(82) },
};

static struct omap_system_dma_plat_info dma_plat_info __initdata = {
	.reg_map	= reg_map,
	.channel_stride	= 0x60,
	.show_dma_caps	= omap2_show_dma_caps,
	.clear_dma	= omap2_clear_dma,
	.dma_write	= dma_write,
	.dma_read	= dma_read,
};

static struct platform_device_info omap_dma_dev_info = {
	.name = "omap-dma-engine",
	.id = -1,
	.dma_mask = DMA_BIT_MASK(32),
};

/* One time initializations */
static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
{
	struct platform_device			*pdev;
	struct omap_system_dma_plat_info	p;
	struct omap_dma_dev_attr		*d;
	struct resource				*mem;
	char					*name = "omap_dma_system";

	p = dma_plat_info;
	p.dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
	p.errata = configure_dma_errata();

	if (!of_have_populated_dt()) {
		if (soc_is_omap24xx()) {
			p.slave_map = omap24xx_sdma_map;
			p.slavecnt = ARRAY_SIZE(omap24xx_sdma_map);
		} else if (soc_is_omap34xx() || soc_is_omap3630()) {
			p.slave_map = omap3xxx_sdma_map;
			p.slavecnt = ARRAY_SIZE(omap3xxx_sdma_map);
		} else {
			pr_err("%s: The legacy DMA map is not provided!\n",
			       __func__);
			return -ENODEV;
		}
	} else {
		if (soc_is_omap24xx()) {
			/* DMA slave map for drivers not yet converted to DT */
			p.slave_map = omap24xx_sdma_dt_map;
			p.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
		}
	}

	pdev = omap_device_build(name, 0, oh, &p, sizeof(p));
	if (IS_ERR(pdev)) {
		pr_err("%s: Can't build omap_device for %s:%s.\n",
			__func__, name, oh->name);
		return PTR_ERR(pdev);
	}

	omap_dma_dev_info.res = pdev->resource;
	omap_dma_dev_info.num_res = pdev->num_resources;

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem) {
		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
		return -EINVAL;
	}

	dma_base = ioremap(mem->start, resource_size(mem));
	if (!dma_base) {
		dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
		return -ENOMEM;
	}

	d = oh->dev_attr;

	if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
		d->dev_caps |= HS_CHANNELS_RESERVED;

	if (platform_get_irq_byname(pdev, "0") < 0)
		d->dev_caps |= DMA_ENGINE_HANDLE_IRQ;

	/* Check the capabilities register for descriptor loading feature */
	if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS)
		dma_common_ch_end = CCDN;
	else
		dma_common_ch_end = CCFN;

	return 0;
}

static int __init omap2_system_dma_init(void)
{
	struct platform_device *pdev;
	int res;

	res = omap_hwmod_for_each_by_class("dma",
			omap2_system_dma_init_dev, NULL);
	if (res)
		return res;

	if (of_have_populated_dt())
		return res;

	pdev = platform_device_register_full(&omap_dma_dev_info);
	if (IS_ERR(pdev))
		return PTR_ERR(pdev);

	return res;
}
omap_arch_initcall(omap2_system_dma_init);