Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/bwh/sfc...
[platform/adaptation/renesas_rcar/renesas_kernel.git] / arch / arm / mach-s3c64xx / dma.c
1 /* linux/arch/arm/plat-s3c64xx/dma.c
2  *
3  * Copyright 2009 Openmoko, Inc.
4  * Copyright 2009 Simtec Electronics
5  *      Ben Dooks <ben@simtec.co.uk>
6  *      http://armlinux.simtec.co.uk/
7  *
8  * S3C64XX DMA core
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/dmapool.h>
19 #include <linux/device.h>
20 #include <linux/errno.h>
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/clk.h>
24 #include <linux/err.h>
25 #include <linux/io.h>
26
27 #include <mach/dma.h>
28 #include <mach/map.h>
29 #include <mach/irqs.h>
30
31 #include <mach/regs-sys.h>
32
33 #include <asm/hardware/pl080.h>
34
35 /* dma channel state information */
36
37 struct s3c64xx_dmac {
38         struct device           dev;
39         struct clk              *clk;
40         void __iomem            *regs;
41         struct s3c2410_dma_chan *channels;
42         enum dma_ch              chanbase;
43 };
44
45 /* pool to provide LLI buffers */
46 static struct dma_pool *dma_pool;
47
48 /* Debug configuration and code */
49
50 static unsigned char debug_show_buffs = 0;
51
52 static void dbg_showchan(struct s3c2410_dma_chan *chan)
53 {
54         pr_debug("DMA%d: %08x->%08x L %08x C %08x,%08x S %08x\n",
55                  chan->number,
56                  readl(chan->regs + PL080_CH_SRC_ADDR),
57                  readl(chan->regs + PL080_CH_DST_ADDR),
58                  readl(chan->regs + PL080_CH_LLI),
59                  readl(chan->regs + PL080_CH_CONTROL),
60                  readl(chan->regs + PL080S_CH_CONTROL2),
61                  readl(chan->regs + PL080S_CH_CONFIG));
62 }
63
64 static void show_lli(struct pl080s_lli *lli)
65 {
66         pr_debug("LLI[%p] %08x->%08x, NL %08x C %08x,%08x\n",
67                  lli, lli->src_addr, lli->dst_addr, lli->next_lli,
68                  lli->control0, lli->control1);
69 }
70
71 static void dbg_showbuffs(struct s3c2410_dma_chan *chan)
72 {
73         struct s3c64xx_dma_buff *ptr;
74         struct s3c64xx_dma_buff *end;
75
76         pr_debug("DMA%d: buffs next %p, curr %p, end %p\n",
77                  chan->number, chan->next, chan->curr, chan->end);
78
79         ptr = chan->next;
80         end = chan->end;
81
82         if (debug_show_buffs) {
83                 for (; ptr != NULL; ptr = ptr->next) {
84                         pr_debug("DMA%d: %08x ",
85                                  chan->number, ptr->lli_dma);
86                         show_lli(ptr->lli);
87                 }
88         }
89 }
90
91 /* End of Debug */
92
93 static struct s3c2410_dma_chan *s3c64xx_dma_map_channel(unsigned int channel)
94 {
95         struct s3c2410_dma_chan *chan;
96         unsigned int start, offs;
97
98         start = 0;
99
100         if (channel >= DMACH_PCM1_TX)
101                 start = 8;
102
103         for (offs = 0; offs < 8; offs++) {
104                 chan = &s3c2410_chans[start + offs];
105                 if (!chan->in_use)
106                         goto found;
107         }
108
109         return NULL;
110
111 found:
112         s3c_dma_chan_map[channel] = chan;
113         return chan;
114 }
115
116 int s3c2410_dma_config(enum dma_ch channel, int xferunit)
117 {
118         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
119
120         if (chan == NULL)
121                 return -EINVAL;
122
123         switch (xferunit) {
124         case 1:
125                 chan->hw_width = 0;
126                 break;
127         case 2:
128                 chan->hw_width = 1;
129                 break;
130         case 4:
131                 chan->hw_width = 2;
132                 break;
133         default:
134                 printk(KERN_ERR "%s: illegal width %d\n", __func__, xferunit);
135                 return -EINVAL;
136         }
137
138         return 0;
139 }
140 EXPORT_SYMBOL(s3c2410_dma_config);
141
142 static void s3c64xx_dma_fill_lli(struct s3c2410_dma_chan *chan,
143                                  struct pl080s_lli *lli,
144                                  dma_addr_t data, int size)
145 {
146         dma_addr_t src, dst;
147         u32 control0, control1;
148
149         switch (chan->source) {
150         case DMA_FROM_DEVICE:
151                 src = chan->dev_addr;
152                 dst = data;
153                 control0 = PL080_CONTROL_SRC_AHB2;
154                 control0 |= PL080_CONTROL_DST_INCR;
155                 break;
156
157         case DMA_TO_DEVICE:
158                 src = data;
159                 dst = chan->dev_addr;
160                 control0 = PL080_CONTROL_DST_AHB2;
161                 control0 |= PL080_CONTROL_SRC_INCR;
162                 break;
163         default:
164                 BUG();
165         }
166
167         /* note, we do not currently setup any of the burst controls */
168
169         control1 = size >> chan->hw_width;      /* size in no of xfers */
170         control0 |= PL080_CONTROL_PROT_SYS;     /* always in priv. mode */
171         control0 |= PL080_CONTROL_TC_IRQ_EN;    /* always fire IRQ */
172         control0 |= (u32)chan->hw_width << PL080_CONTROL_DWIDTH_SHIFT;
173         control0 |= (u32)chan->hw_width << PL080_CONTROL_SWIDTH_SHIFT;
174
175         lli->src_addr = src;
176         lli->dst_addr = dst;
177         lli->next_lli = 0;
178         lli->control0 = control0;
179         lli->control1 = control1;
180 }
181
182 static void s3c64xx_lli_to_regs(struct s3c2410_dma_chan *chan,
183                                 struct pl080s_lli *lli)
184 {
185         void __iomem *regs = chan->regs;
186
187         pr_debug("%s: LLI %p => regs\n", __func__, lli);
188         show_lli(lli);
189
190         writel(lli->src_addr, regs + PL080_CH_SRC_ADDR);
191         writel(lli->dst_addr, regs + PL080_CH_DST_ADDR);
192         writel(lli->next_lli, regs + PL080_CH_LLI);
193         writel(lli->control0, regs + PL080_CH_CONTROL);
194         writel(lli->control1, regs + PL080S_CH_CONTROL2);
195 }
196
197 static int s3c64xx_dma_start(struct s3c2410_dma_chan *chan)
198 {
199         struct s3c64xx_dmac *dmac = chan->dmac;
200         u32 config;
201         u32 bit = chan->bit;
202
203         dbg_showchan(chan);
204
205         pr_debug("%s: clearing interrupts\n", __func__);
206
207         /* clear interrupts */
208         writel(bit, dmac->regs + PL080_TC_CLEAR);
209         writel(bit, dmac->regs + PL080_ERR_CLEAR);
210
211         pr_debug("%s: starting channel\n", __func__);
212
213         config = readl(chan->regs + PL080S_CH_CONFIG);
214         config |= PL080_CONFIG_ENABLE;
215         config &= ~PL080_CONFIG_HALT;
216
217         pr_debug("%s: writing config %08x\n", __func__, config);
218         writel(config, chan->regs + PL080S_CH_CONFIG);
219
220         return 0;
221 }
222
223 static int s3c64xx_dma_stop(struct s3c2410_dma_chan *chan)
224 {
225         u32 config;
226         int timeout;
227
228         pr_debug("%s: stopping channel\n", __func__);
229
230         dbg_showchan(chan);
231
232         config = readl(chan->regs + PL080S_CH_CONFIG);
233         config |= PL080_CONFIG_HALT;
234         writel(config, chan->regs + PL080S_CH_CONFIG);
235
236         timeout = 1000;
237         do {
238                 config = readl(chan->regs + PL080S_CH_CONFIG);
239                 pr_debug("%s: %d - config %08x\n", __func__, timeout, config);
240                 if (config & PL080_CONFIG_ACTIVE)
241                         udelay(10);
242                 else
243                         break;
244                 } while (--timeout > 0);
245
246         if (config & PL080_CONFIG_ACTIVE) {
247                 printk(KERN_ERR "%s: channel still active\n", __func__);
248                 return -EFAULT;
249         }
250
251         config = readl(chan->regs + PL080S_CH_CONFIG);
252         config &= ~PL080_CONFIG_ENABLE;
253         writel(config, chan->regs + PL080S_CH_CONFIG);
254
255         return 0;
256 }
257
258 static inline void s3c64xx_dma_bufffdone(struct s3c2410_dma_chan *chan,
259                                          struct s3c64xx_dma_buff *buf,
260                                          enum s3c2410_dma_buffresult result)
261 {
262         if (chan->callback_fn != NULL)
263                 (chan->callback_fn)(chan, buf->pw, 0, result);
264 }
265
266 static void s3c64xx_dma_freebuff(struct s3c64xx_dma_buff *buff)
267 {
268         dma_pool_free(dma_pool, buff->lli, buff->lli_dma);
269         kfree(buff);
270 }
271
272 static int s3c64xx_dma_flush(struct s3c2410_dma_chan *chan)
273 {
274         struct s3c64xx_dma_buff *buff, *next;
275         u32 config;
276
277         dbg_showchan(chan);
278
279         pr_debug("%s: flushing channel\n", __func__);
280
281         config = readl(chan->regs + PL080S_CH_CONFIG);
282         config &= ~PL080_CONFIG_ENABLE;
283         writel(config, chan->regs + PL080S_CH_CONFIG);
284
285         /* dump all the buffers associated with this channel */
286
287         for (buff = chan->curr; buff != NULL; buff = next) {
288                 next = buff->next;
289                 pr_debug("%s: buff %p (next %p)\n", __func__, buff, buff->next);
290
291                 s3c64xx_dma_bufffdone(chan, buff, S3C2410_RES_ABORT);
292                 s3c64xx_dma_freebuff(buff);
293         }
294
295         chan->curr = chan->next = chan->end = NULL;
296
297         return 0;
298 }
299
300 int s3c2410_dma_ctrl(enum dma_ch channel, enum s3c2410_chan_op op)
301 {
302         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
303
304         WARN_ON(!chan);
305         if (!chan)
306                 return -EINVAL;
307
308         switch (op) {
309         case S3C2410_DMAOP_START:
310                 return s3c64xx_dma_start(chan);
311
312         case S3C2410_DMAOP_STOP:
313                 return s3c64xx_dma_stop(chan);
314
315         case S3C2410_DMAOP_FLUSH:
316                 return s3c64xx_dma_flush(chan);
317
318         /* believe PAUSE/RESUME are no-ops */
319         case S3C2410_DMAOP_PAUSE:
320         case S3C2410_DMAOP_RESUME:
321         case S3C2410_DMAOP_STARTED:
322         case S3C2410_DMAOP_TIMEOUT:
323                 return 0;
324         }
325
326         return -ENOENT;
327 }
328 EXPORT_SYMBOL(s3c2410_dma_ctrl);
329
330 /* s3c2410_dma_enque
331  *
332  */
333
334 int s3c2410_dma_enqueue(enum dma_ch channel, void *id,
335                         dma_addr_t data, int size)
336 {
337         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
338         struct s3c64xx_dma_buff *next;
339         struct s3c64xx_dma_buff *buff;
340         struct pl080s_lli *lli;
341         unsigned long flags;
342         int ret;
343
344         WARN_ON(!chan);
345         if (!chan)
346                 return -EINVAL;
347
348         buff = kzalloc(sizeof(struct s3c64xx_dma_buff), GFP_ATOMIC);
349         if (!buff) {
350                 printk(KERN_ERR "%s: no memory for buffer\n", __func__);
351                 return -ENOMEM;
352         }
353
354         lli = dma_pool_alloc(dma_pool, GFP_ATOMIC, &buff->lli_dma);
355         if (!lli) {
356                 printk(KERN_ERR "%s: no memory for lli\n", __func__);
357                 ret = -ENOMEM;
358                 goto err_buff;
359         }
360
361         pr_debug("%s: buff %p, dp %08x lli (%p, %08x) %d\n",
362                  __func__, buff, data, lli, (u32)buff->lli_dma, size);
363
364         buff->lli = lli;
365         buff->pw = id;
366
367         s3c64xx_dma_fill_lli(chan, lli, data, size);
368
369         local_irq_save(flags);
370
371         if ((next = chan->next) != NULL) {
372                 struct s3c64xx_dma_buff *end = chan->end;
373                 struct pl080s_lli *endlli = end->lli;
374
375                 pr_debug("enquing onto channel\n");
376
377                 end->next = buff;
378                 endlli->next_lli = buff->lli_dma;
379
380                 if (chan->flags & S3C2410_DMAF_CIRCULAR) {
381                         struct s3c64xx_dma_buff *curr = chan->curr;
382                         lli->next_lli = curr->lli_dma;
383                 }
384
385                 if (next == chan->curr) {
386                         writel(buff->lli_dma, chan->regs + PL080_CH_LLI);
387                         chan->next = buff;
388                 }
389
390                 show_lli(endlli);
391                 chan->end = buff;
392         } else {
393                 pr_debug("enquing onto empty channel\n");
394
395                 chan->curr = buff;
396                 chan->next = buff;
397                 chan->end = buff;
398
399                 s3c64xx_lli_to_regs(chan, lli);
400         }
401
402         local_irq_restore(flags);
403
404         show_lli(lli);
405
406         dbg_showchan(chan);
407         dbg_showbuffs(chan);
408         return 0;
409
410 err_buff:
411         kfree(buff);
412         return ret;
413 }
414
415 EXPORT_SYMBOL(s3c2410_dma_enqueue);
416
417
418 int s3c2410_dma_devconfig(enum dma_ch channel,
419                           enum dma_data_direction source,
420                           unsigned long devaddr)
421 {
422         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
423         u32 peripheral;
424         u32 config = 0;
425
426         pr_debug("%s: channel %d, source %d, dev %08lx, chan %p\n",
427                  __func__, channel, source, devaddr, chan);
428
429         WARN_ON(!chan);
430         if (!chan)
431                 return -EINVAL;
432
433         peripheral = (chan->peripheral & 0xf);
434         chan->source = source;
435         chan->dev_addr = devaddr;
436
437         pr_debug("%s: peripheral %d\n", __func__, peripheral);
438
439         switch (source) {
440         case DMA_FROM_DEVICE:
441                 config = 2 << PL080_CONFIG_FLOW_CONTROL_SHIFT;
442                 config |= peripheral << PL080_CONFIG_SRC_SEL_SHIFT;
443                 break;
444         case DMA_TO_DEVICE:
445                 config = 1 << PL080_CONFIG_FLOW_CONTROL_SHIFT;
446                 config |= peripheral << PL080_CONFIG_DST_SEL_SHIFT;
447                 break;
448         default:
449                 printk(KERN_ERR "%s: bad source\n", __func__);
450                 return -EINVAL;
451         }
452
453         /* allow TC and ERR interrupts */
454         config |= PL080_CONFIG_TC_IRQ_MASK;
455         config |= PL080_CONFIG_ERR_IRQ_MASK;
456
457         pr_debug("%s: config %08x\n", __func__, config);
458
459         writel(config, chan->regs + PL080S_CH_CONFIG);
460
461         return 0;
462 }
463 EXPORT_SYMBOL(s3c2410_dma_devconfig);
464
465
466 int s3c2410_dma_getposition(enum dma_ch channel,
467                             dma_addr_t *src, dma_addr_t *dst)
468 {
469         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
470
471         WARN_ON(!chan);
472         if (!chan)
473                 return -EINVAL;
474
475         if (src != NULL)
476                 *src = readl(chan->regs + PL080_CH_SRC_ADDR);
477
478         if (dst != NULL)
479                 *dst = readl(chan->regs + PL080_CH_DST_ADDR);
480
481         return 0;
482 }
483 EXPORT_SYMBOL(s3c2410_dma_getposition);
484
485 /* s3c2410_request_dma
486  *
487  * get control of an dma channel
488 */
489
490 int s3c2410_dma_request(enum dma_ch channel,
491                         struct s3c2410_dma_client *client,
492                         void *dev)
493 {
494         struct s3c2410_dma_chan *chan;
495         unsigned long flags;
496
497         pr_debug("dma%d: s3c2410_request_dma: client=%s, dev=%p\n",
498                  channel, client->name, dev);
499
500         local_irq_save(flags);
501
502         chan = s3c64xx_dma_map_channel(channel);
503         if (chan == NULL) {
504                 local_irq_restore(flags);
505                 return -EBUSY;
506         }
507
508         dbg_showchan(chan);
509
510         chan->client = client;
511         chan->in_use = 1;
512         chan->peripheral = channel;
513
514         local_irq_restore(flags);
515
516         /* need to setup */
517
518         pr_debug("%s: channel initialised, %p\n", __func__, chan);
519
520         return chan->number | DMACH_LOW_LEVEL;
521 }
522
523 EXPORT_SYMBOL(s3c2410_dma_request);
524
525 /* s3c2410_dma_free
526  *
527  * release the given channel back to the system, will stop and flush
528  * any outstanding transfers, and ensure the channel is ready for the
529  * next claimant.
530  *
531  * Note, although a warning is currently printed if the freeing client
532  * info is not the same as the registrant's client info, the free is still
533  * allowed to go through.
534 */
535
536 int s3c2410_dma_free(enum dma_ch channel, struct s3c2410_dma_client *client)
537 {
538         struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
539         unsigned long flags;
540
541         if (chan == NULL)
542                 return -EINVAL;
543
544         local_irq_save(flags);
545
546         if (chan->client != client) {
547                 printk(KERN_WARNING "dma%d: possible free from different client (channel %p, passed %p)\n",
548                        channel, chan->client, client);
549         }
550
551         /* sort out stopping and freeing the channel */
552
553
554         chan->client = NULL;
555         chan->in_use = 0;
556
557         if (!(channel & DMACH_LOW_LEVEL))
558                 s3c_dma_chan_map[channel] = NULL;
559
560         local_irq_restore(flags);
561
562         return 0;
563 }
564
565 EXPORT_SYMBOL(s3c2410_dma_free);
566
567 static irqreturn_t s3c64xx_dma_irq(int irq, void *pw)
568 {
569         struct s3c64xx_dmac *dmac = pw;
570         struct s3c2410_dma_chan *chan;
571         enum s3c2410_dma_buffresult res;
572         u32 tcstat, errstat;
573         u32 bit;
574         int offs;
575
576         tcstat = readl(dmac->regs + PL080_TC_STATUS);
577         errstat = readl(dmac->regs + PL080_ERR_STATUS);
578
579         for (offs = 0, bit = 1; offs < 8; offs++, bit <<= 1) {
580                 struct s3c64xx_dma_buff *buff;
581
582                 if (!(errstat & bit) && !(tcstat & bit))
583                         continue;
584
585                 chan = dmac->channels + offs;
586                 res = S3C2410_RES_ERR;
587
588                 if (tcstat & bit) {
589                         writel(bit, dmac->regs + PL080_TC_CLEAR);
590                         res = S3C2410_RES_OK;
591                 }
592
593                 if (errstat & bit)
594                         writel(bit, dmac->regs + PL080_ERR_CLEAR);
595
596                 /* 'next' points to the buffer that is next to the
597                  * currently active buffer.
598                  * For CIRCULAR queues, 'next' will be same as 'curr'
599                  * when 'end' is the active buffer.
600                  */
601                 buff = chan->curr;
602                 while (buff && buff != chan->next
603                                 && buff->next != chan->next)
604                         buff = buff->next;
605
606                 if (!buff)
607                         BUG();
608
609                 if (buff == chan->next)
610                         buff = chan->end;
611
612                 s3c64xx_dma_bufffdone(chan, buff, res);
613
614                 /* Free the node and update curr, if non-circular queue */
615                 if (!(chan->flags & S3C2410_DMAF_CIRCULAR)) {
616                         chan->curr = buff->next;
617                         s3c64xx_dma_freebuff(buff);
618                 }
619
620                 /* Update 'next' */
621                 buff = chan->next;
622                 if (chan->next == chan->end) {
623                         chan->next = chan->curr;
624                         if (!(chan->flags & S3C2410_DMAF_CIRCULAR))
625                                 chan->end = NULL;
626                 } else {
627                         chan->next = buff->next;
628                 }
629         }
630
631         return IRQ_HANDLED;
632 }
633
634 static struct bus_type dma_subsys = {
635         .name           = "s3c64xx-dma",
636         .dev_name       = "s3c64xx-dma",
637 };
638
639 static int s3c64xx_dma_init1(int chno, enum dma_ch chbase,
640                              int irq, unsigned int base)
641 {
642         struct s3c2410_dma_chan *chptr = &s3c2410_chans[chno];
643         struct s3c64xx_dmac *dmac;
644         char clkname[16];
645         void __iomem *regs;
646         void __iomem *regptr;
647         int err, ch;
648
649         dmac = kzalloc(sizeof(struct s3c64xx_dmac), GFP_KERNEL);
650         if (!dmac) {
651                 printk(KERN_ERR "%s: failed to alloc mem\n", __func__);
652                 return -ENOMEM;
653         }
654
655         dmac->dev.id = chno / 8;
656         dmac->dev.bus = &dma_subsys;
657
658         err = device_register(&dmac->dev);
659         if (err) {
660                 printk(KERN_ERR "%s: failed to register device\n", __func__);
661                 goto err_alloc;
662         }
663
664         regs = ioremap(base, 0x200);
665         if (!regs) {
666                 printk(KERN_ERR "%s: failed to ioremap()\n", __func__);
667                 err = -ENXIO;
668                 goto err_dev;
669         }
670
671         snprintf(clkname, sizeof(clkname), "dma%d", dmac->dev.id);
672
673         dmac->clk = clk_get(NULL, clkname);
674         if (IS_ERR(dmac->clk)) {
675                 printk(KERN_ERR "%s: failed to get clock %s\n", __func__, clkname);
676                 err = PTR_ERR(dmac->clk);
677                 goto err_map;
678         }
679
680         clk_enable(dmac->clk);
681
682         dmac->regs = regs;
683         dmac->chanbase = chbase;
684         dmac->channels = chptr;
685
686         err = request_irq(irq, s3c64xx_dma_irq, 0, "DMA", dmac);
687         if (err < 0) {
688                 printk(KERN_ERR "%s: failed to get irq\n", __func__);
689                 goto err_clk;
690         }
691
692         regptr = regs + PL080_Cx_BASE(0);
693
694         for (ch = 0; ch < 8; ch++, chptr++) {
695                 pr_debug("%s: registering DMA %d (%p)\n",
696                          __func__, chno + ch, regptr);
697
698                 chptr->bit = 1 << ch;
699                 chptr->number = chno + ch;
700                 chptr->dmac = dmac;
701                 chptr->regs = regptr;
702                 regptr += PL080_Cx_STRIDE;
703         }
704
705         /* for the moment, permanently enable the controller */
706         writel(PL080_CONFIG_ENABLE, regs + PL080_CONFIG);
707
708         printk(KERN_INFO "PL080: IRQ %d, at %p, channels %d..%d\n",
709                irq, regs, chno, chno+8);
710
711         return 0;
712
713 err_clk:
714         clk_disable(dmac->clk);
715         clk_put(dmac->clk);
716 err_map:
717         iounmap(regs);
718 err_dev:
719         device_unregister(&dmac->dev);
720 err_alloc:
721         kfree(dmac);
722         return err;
723 }
724
725 static int __init s3c64xx_dma_init(void)
726 {
727         int ret;
728
729         printk(KERN_INFO "%s: Registering DMA channels\n", __func__);
730
731         dma_pool = dma_pool_create("DMA-LLI", NULL, sizeof(struct pl080s_lli), 16, 0);
732         if (!dma_pool) {
733                 printk(KERN_ERR "%s: failed to create pool\n", __func__);
734                 return -ENOMEM;
735         }
736
737         ret = subsys_system_register(&dma_subsys, NULL);
738         if (ret) {
739                 printk(KERN_ERR "%s: failed to create subsys\n", __func__);
740                 return -ENOMEM;
741         }
742
743         /* Set all DMA configuration to be DMA, not SDMA */
744         writel(0xffffff, S3C64XX_SDMA_SEL);
745
746         /* Register standard DMA controllers */
747         s3c64xx_dma_init1(0, DMACH_UART0, IRQ_DMA0, 0x75000000);
748         s3c64xx_dma_init1(8, DMACH_PCM1_TX, IRQ_DMA1, 0x75100000);
749
750         return 0;
751 }
752
753 arch_initcall(s3c64xx_dma_init);