pch_dma: set the number of array correctly
[linux-2.6.git] / drivers / dma / pch_dma.c
1 /*
2  * Topcliff PCH DMA controller driver
3  * Copyright (c) 2010 Intel Corporation
4  * Copyright (C) 2011 OKI SEMICONDUCTOR CO., LTD.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19
20 #include <linux/dmaengine.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/init.h>
23 #include <linux/pci.h>
24 #include <linux/interrupt.h>
25 #include <linux/module.h>
26 #include <linux/pch_dma.h>
27
28 #define DRV_NAME "pch-dma"
29
30 #define DMA_CTL0_DISABLE                0x0
31 #define DMA_CTL0_SG                     0x1
32 #define DMA_CTL0_ONESHOT                0x2
33 #define DMA_CTL0_MODE_MASK_BITS         0x3
34 #define DMA_CTL0_DIR_SHIFT_BITS         2
35 #define DMA_CTL0_BITS_PER_CH            4
36
37 #define DMA_CTL2_START_SHIFT_BITS       8
38 #define DMA_CTL2_IRQ_ENABLE_MASK        ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)
39
40 #define DMA_STATUS_IDLE                 0x0
41 #define DMA_STATUS_DESC_READ            0x1
42 #define DMA_STATUS_WAIT                 0x2
43 #define DMA_STATUS_ACCESS               0x3
44 #define DMA_STATUS_BITS_PER_CH          2
45 #define DMA_STATUS_MASK_BITS            0x3
46 #define DMA_STATUS_SHIFT_BITS           16
47 #define DMA_STATUS_IRQ(x)               (0x1 << (x))
48 #define DMA_STATUS_ERR(x)               (0x1 << ((x) + 8))
49
50 #define DMA_DESC_WIDTH_SHIFT_BITS       12
51 #define DMA_DESC_WIDTH_1_BYTE           (0x3 << DMA_DESC_WIDTH_SHIFT_BITS)
52 #define DMA_DESC_WIDTH_2_BYTES          (0x2 << DMA_DESC_WIDTH_SHIFT_BITS)
53 #define DMA_DESC_WIDTH_4_BYTES          (0x0 << DMA_DESC_WIDTH_SHIFT_BITS)
54 #define DMA_DESC_MAX_COUNT_1_BYTE       0x3FF
55 #define DMA_DESC_MAX_COUNT_2_BYTES      0x3FF
56 #define DMA_DESC_MAX_COUNT_4_BYTES      0x7FF
57 #define DMA_DESC_END_WITHOUT_IRQ        0x0
58 #define DMA_DESC_END_WITH_IRQ           0x1
59 #define DMA_DESC_FOLLOW_WITHOUT_IRQ     0x2
60 #define DMA_DESC_FOLLOW_WITH_IRQ        0x3
61
62 #define MAX_CHAN_NR                     8
63
64 static unsigned int init_nr_desc_per_channel = 64;
65 module_param(init_nr_desc_per_channel, uint, 0644);
66 MODULE_PARM_DESC(init_nr_desc_per_channel,
67                  "initial descriptors per channel (default: 64)");
68
69 struct pch_dma_desc_regs {
70         u32     dev_addr;
71         u32     mem_addr;
72         u32     size;
73         u32     next;
74 };
75
76 struct pch_dma_regs {
77         u32     dma_ctl0;
78         u32     dma_ctl1;
79         u32     dma_ctl2;
80         u32     reserved1;
81         u32     dma_sts0;
82         u32     dma_sts1;
83         u32     reserved2;
84         u32     reserved3;
85         struct pch_dma_desc_regs desc[MAX_CHAN_NR];
86 };
87
88 struct pch_dma_desc {
89         struct pch_dma_desc_regs regs;
90         struct dma_async_tx_descriptor txd;
91         struct list_head        desc_node;
92         struct list_head        tx_list;
93 };
94
95 struct pch_dma_chan {
96         struct dma_chan         chan;
97         void __iomem *membase;
98         enum dma_data_direction dir;
99         struct tasklet_struct   tasklet;
100         unsigned long           err_status;
101
102         spinlock_t              lock;
103
104         dma_cookie_t            completed_cookie;
105         struct list_head        active_list;
106         struct list_head        queue;
107         struct list_head        free_list;
108         unsigned int            descs_allocated;
109 };
110
111 #define PDC_DEV_ADDR    0x00
112 #define PDC_MEM_ADDR    0x04
113 #define PDC_SIZE        0x08
114 #define PDC_NEXT        0x0C
115
116 #define channel_readl(pdc, name) \
117         readl((pdc)->membase + PDC_##name)
118 #define channel_writel(pdc, name, val) \
119         writel((val), (pdc)->membase + PDC_##name)
120
121 struct pch_dma {
122         struct dma_device       dma;
123         void __iomem *membase;
124         struct pci_pool         *pool;
125         struct pch_dma_regs     regs;
126         struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
127         struct pch_dma_chan     channels[MAX_CHAN_NR];
128 };
129
130 #define PCH_DMA_CTL0    0x00
131 #define PCH_DMA_CTL1    0x04
132 #define PCH_DMA_CTL2    0x08
133 #define PCH_DMA_STS0    0x10
134 #define PCH_DMA_STS1    0x14
135
136 #define dma_readl(pd, name) \
137         readl((pd)->membase + PCH_DMA_##name)
138 #define dma_writel(pd, name, val) \
139         writel((val), (pd)->membase + PCH_DMA_##name)
140
141 static inline struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
142 {
143         return container_of(txd, struct pch_dma_desc, txd);
144 }
145
146 static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
147 {
148         return container_of(chan, struct pch_dma_chan, chan);
149 }
150
151 static inline struct pch_dma *to_pd(struct dma_device *ddev)
152 {
153         return container_of(ddev, struct pch_dma, dma);
154 }
155
156 static inline struct device *chan2dev(struct dma_chan *chan)
157 {
158         return &chan->dev->device;
159 }
160
161 static inline struct device *chan2parent(struct dma_chan *chan)
162 {
163         return chan->dev->device.parent;
164 }
165
166 static inline struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
167 {
168         return list_first_entry(&pd_chan->active_list,
169                                 struct pch_dma_desc, desc_node);
170 }
171
172 static inline struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
173 {
174         return list_first_entry(&pd_chan->queue,
175                                 struct pch_dma_desc, desc_node);
176 }
177
178 static void pdc_enable_irq(struct dma_chan *chan, int enable)
179 {
180         struct pch_dma *pd = to_pd(chan->device);
181         u32 val;
182
183         val = dma_readl(pd, CTL2);
184
185         if (enable)
186                 val |= 0x1 << chan->chan_id;
187         else
188                 val &= ~(0x1 << chan->chan_id);
189
190         dma_writel(pd, CTL2, val);
191
192         dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
193                 chan->chan_id, val);
194 }
195
196 static void pdc_set_dir(struct dma_chan *chan)
197 {
198         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
199         struct pch_dma *pd = to_pd(chan->device);
200         u32 val;
201
202         val = dma_readl(pd, CTL0);
203
204         if (pd_chan->dir == DMA_TO_DEVICE)
205                 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
206                                DMA_CTL0_DIR_SHIFT_BITS);
207         else
208                 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
209                                  DMA_CTL0_DIR_SHIFT_BITS));
210
211         dma_writel(pd, CTL0, val);
212
213         dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
214                 chan->chan_id, val);
215 }
216
217 static void pdc_set_mode(struct dma_chan *chan, u32 mode)
218 {
219         struct pch_dma *pd = to_pd(chan->device);
220         u32 val;
221
222         val = dma_readl(pd, CTL0);
223
224         val &= ~(DMA_CTL0_MODE_MASK_BITS <<
225                 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
226         val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
227
228         dma_writel(pd, CTL0, val);
229
230         dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
231                 chan->chan_id, val);
232 }
233
234 static u32 pdc_get_status(struct pch_dma_chan *pd_chan)
235 {
236         struct pch_dma *pd = to_pd(pd_chan->chan.device);
237         u32 val;
238
239         val = dma_readl(pd, STS0);
240         return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
241                         DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
242 }
243
244 static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
245 {
246         if (pdc_get_status(pd_chan) == DMA_STATUS_IDLE)
247                 return true;
248         else
249                 return false;
250 }
251
252 static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
253 {
254         struct pch_dma *pd = to_pd(pd_chan->chan.device);
255         u32 val;
256
257         if (!pdc_is_idle(pd_chan)) {
258                 dev_err(chan2dev(&pd_chan->chan),
259                         "BUG: Attempt to start non-idle channel\n");
260                 return;
261         }
262
263         dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
264                 pd_chan->chan.chan_id, desc->regs.dev_addr);
265         dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
266                 pd_chan->chan.chan_id, desc->regs.mem_addr);
267         dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
268                 pd_chan->chan.chan_id, desc->regs.size);
269         dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
270                 pd_chan->chan.chan_id, desc->regs.next);
271
272         if (list_empty(&desc->tx_list)) {
273                 channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
274                 channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
275                 channel_writel(pd_chan, SIZE, desc->regs.size);
276                 channel_writel(pd_chan, NEXT, desc->regs.next);
277                 pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
278         } else {
279                 channel_writel(pd_chan, NEXT, desc->txd.phys);
280                 pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
281         }
282
283         val = dma_readl(pd, CTL2);
284         val |= 1 << (DMA_CTL2_START_SHIFT_BITS + pd_chan->chan.chan_id);
285         dma_writel(pd, CTL2, val);
286 }
287
288 static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
289                                struct pch_dma_desc *desc)
290 {
291         struct dma_async_tx_descriptor *txd = &desc->txd;
292         dma_async_tx_callback callback = txd->callback;
293         void *param = txd->callback_param;
294
295         list_splice_init(&desc->tx_list, &pd_chan->free_list);
296         list_move(&desc->desc_node, &pd_chan->free_list);
297
298         if (callback)
299                 callback(param);
300 }
301
302 static void pdc_complete_all(struct pch_dma_chan *pd_chan)
303 {
304         struct pch_dma_desc *desc, *_d;
305         LIST_HEAD(list);
306
307         BUG_ON(!pdc_is_idle(pd_chan));
308
309         if (!list_empty(&pd_chan->queue))
310                 pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
311
312         list_splice_init(&pd_chan->active_list, &list);
313         list_splice_init(&pd_chan->queue, &pd_chan->active_list);
314
315         list_for_each_entry_safe(desc, _d, &list, desc_node)
316                 pdc_chain_complete(pd_chan, desc);
317 }
318
319 static void pdc_handle_error(struct pch_dma_chan *pd_chan)
320 {
321         struct pch_dma_desc *bad_desc;
322
323         bad_desc = pdc_first_active(pd_chan);
324         list_del(&bad_desc->desc_node);
325
326         list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
327
328         if (!list_empty(&pd_chan->active_list))
329                 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
330
331         dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
332         dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
333                  bad_desc->txd.cookie);
334
335         pdc_chain_complete(pd_chan, bad_desc);
336 }
337
338 static void pdc_advance_work(struct pch_dma_chan *pd_chan)
339 {
340         if (list_empty(&pd_chan->active_list) ||
341                 list_is_singular(&pd_chan->active_list)) {
342                 pdc_complete_all(pd_chan);
343         } else {
344                 pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
345                 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
346         }
347 }
348
349 static dma_cookie_t pdc_assign_cookie(struct pch_dma_chan *pd_chan,
350                                       struct pch_dma_desc *desc)
351 {
352         dma_cookie_t cookie = pd_chan->chan.cookie;
353
354         if (++cookie < 0)
355                 cookie = 1;
356
357         pd_chan->chan.cookie = cookie;
358         desc->txd.cookie = cookie;
359
360         return cookie;
361 }
362
363 static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
364 {
365         struct pch_dma_desc *desc = to_pd_desc(txd);
366         struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
367         dma_cookie_t cookie;
368
369         spin_lock(&pd_chan->lock);
370         cookie = pdc_assign_cookie(pd_chan, desc);
371
372         if (list_empty(&pd_chan->active_list)) {
373                 list_add_tail(&desc->desc_node, &pd_chan->active_list);
374                 pdc_dostart(pd_chan, desc);
375         } else {
376                 list_add_tail(&desc->desc_node, &pd_chan->queue);
377         }
378
379         spin_unlock(&pd_chan->lock);
380         return 0;
381 }
382
383 static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
384 {
385         struct pch_dma_desc *desc = NULL;
386         struct pch_dma *pd = to_pd(chan->device);
387         dma_addr_t addr;
388
389         desc = pci_pool_alloc(pd->pool, flags, &addr);
390         if (desc) {
391                 memset(desc, 0, sizeof(struct pch_dma_desc));
392                 INIT_LIST_HEAD(&desc->tx_list);
393                 dma_async_tx_descriptor_init(&desc->txd, chan);
394                 desc->txd.tx_submit = pd_tx_submit;
395                 desc->txd.flags = DMA_CTRL_ACK;
396                 desc->txd.phys = addr;
397         }
398
399         return desc;
400 }
401
402 static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
403 {
404         struct pch_dma_desc *desc, *_d;
405         struct pch_dma_desc *ret = NULL;
406         int i;
407
408         spin_lock(&pd_chan->lock);
409         list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
410                 i++;
411                 if (async_tx_test_ack(&desc->txd)) {
412                         list_del(&desc->desc_node);
413                         ret = desc;
414                         break;
415                 }
416                 dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
417         }
418         spin_unlock(&pd_chan->lock);
419         dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
420
421         if (!ret) {
422                 ret = pdc_alloc_desc(&pd_chan->chan, GFP_NOIO);
423                 if (ret) {
424                         spin_lock(&pd_chan->lock);
425                         pd_chan->descs_allocated++;
426                         spin_unlock(&pd_chan->lock);
427                 } else {
428                         dev_err(chan2dev(&pd_chan->chan),
429                                 "failed to alloc desc\n");
430                 }
431         }
432
433         return ret;
434 }
435
436 static void pdc_desc_put(struct pch_dma_chan *pd_chan,
437                          struct pch_dma_desc *desc)
438 {
439         if (desc) {
440                 spin_lock(&pd_chan->lock);
441                 list_splice_init(&desc->tx_list, &pd_chan->free_list);
442                 list_add(&desc->desc_node, &pd_chan->free_list);
443                 spin_unlock(&pd_chan->lock);
444         }
445 }
446
447 static int pd_alloc_chan_resources(struct dma_chan *chan)
448 {
449         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
450         struct pch_dma_desc *desc;
451         LIST_HEAD(tmp_list);
452         int i;
453
454         if (!pdc_is_idle(pd_chan)) {
455                 dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
456                 return -EIO;
457         }
458
459         if (!list_empty(&pd_chan->free_list))
460                 return pd_chan->descs_allocated;
461
462         for (i = 0; i < init_nr_desc_per_channel; i++) {
463                 desc = pdc_alloc_desc(chan, GFP_KERNEL);
464
465                 if (!desc) {
466                         dev_warn(chan2dev(chan),
467                                 "Only allocated %d initial descriptors\n", i);
468                         break;
469                 }
470
471                 list_add_tail(&desc->desc_node, &tmp_list);
472         }
473
474         spin_lock_bh(&pd_chan->lock);
475         list_splice(&tmp_list, &pd_chan->free_list);
476         pd_chan->descs_allocated = i;
477         pd_chan->completed_cookie = chan->cookie = 1;
478         spin_unlock_bh(&pd_chan->lock);
479
480         pdc_enable_irq(chan, 1);
481         pdc_set_dir(chan);
482
483         return pd_chan->descs_allocated;
484 }
485
486 static void pd_free_chan_resources(struct dma_chan *chan)
487 {
488         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
489         struct pch_dma *pd = to_pd(chan->device);
490         struct pch_dma_desc *desc, *_d;
491         LIST_HEAD(tmp_list);
492
493         BUG_ON(!pdc_is_idle(pd_chan));
494         BUG_ON(!list_empty(&pd_chan->active_list));
495         BUG_ON(!list_empty(&pd_chan->queue));
496
497         spin_lock_bh(&pd_chan->lock);
498         list_splice_init(&pd_chan->free_list, &tmp_list);
499         pd_chan->descs_allocated = 0;
500         spin_unlock_bh(&pd_chan->lock);
501
502         list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
503                 pci_pool_free(pd->pool, desc, desc->txd.phys);
504
505         pdc_enable_irq(chan, 0);
506 }
507
508 static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
509                                     struct dma_tx_state *txstate)
510 {
511         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
512         dma_cookie_t last_used;
513         dma_cookie_t last_completed;
514         int ret;
515
516         spin_lock_bh(&pd_chan->lock);
517         last_completed = pd_chan->completed_cookie;
518         last_used = chan->cookie;
519         spin_unlock_bh(&pd_chan->lock);
520
521         ret = dma_async_is_complete(cookie, last_completed, last_used);
522
523         dma_set_tx_state(txstate, last_completed, last_used, 0);
524
525         return ret;
526 }
527
528 static void pd_issue_pending(struct dma_chan *chan)
529 {
530         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
531
532         if (pdc_is_idle(pd_chan)) {
533                 spin_lock(&pd_chan->lock);
534                 pdc_advance_work(pd_chan);
535                 spin_unlock(&pd_chan->lock);
536         }
537 }
538
539 static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,
540                         struct scatterlist *sgl, unsigned int sg_len,
541                         enum dma_data_direction direction, unsigned long flags)
542 {
543         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
544         struct pch_dma_slave *pd_slave = chan->private;
545         struct pch_dma_desc *first = NULL;
546         struct pch_dma_desc *prev = NULL;
547         struct pch_dma_desc *desc = NULL;
548         struct scatterlist *sg;
549         dma_addr_t reg;
550         int i;
551
552         if (unlikely(!sg_len)) {
553                 dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
554                 return NULL;
555         }
556
557         if (direction == DMA_FROM_DEVICE)
558                 reg = pd_slave->rx_reg;
559         else if (direction == DMA_TO_DEVICE)
560                 reg = pd_slave->tx_reg;
561         else
562                 return NULL;
563
564         for_each_sg(sgl, sg, sg_len, i) {
565                 desc = pdc_desc_get(pd_chan);
566
567                 if (!desc)
568                         goto err_desc_get;
569
570                 desc->regs.dev_addr = reg;
571                 desc->regs.mem_addr = sg_phys(sg);
572                 desc->regs.size = sg_dma_len(sg);
573                 desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
574
575                 switch (pd_slave->width) {
576                 case PCH_DMA_WIDTH_1_BYTE:
577                         if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
578                                 goto err_desc_get;
579                         desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
580                         break;
581                 case PCH_DMA_WIDTH_2_BYTES:
582                         if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
583                                 goto err_desc_get;
584                         desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
585                         break;
586                 case PCH_DMA_WIDTH_4_BYTES:
587                         if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
588                                 goto err_desc_get;
589                         desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
590                         break;
591                 default:
592                         goto err_desc_get;
593                 }
594
595                 if (!first) {
596                         first = desc;
597                 } else {
598                         prev->regs.next |= desc->txd.phys;
599                         list_add_tail(&desc->desc_node, &first->tx_list);
600                 }
601
602                 prev = desc;
603         }
604
605         if (flags & DMA_PREP_INTERRUPT)
606                 desc->regs.next = DMA_DESC_END_WITH_IRQ;
607         else
608                 desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
609
610         first->txd.cookie = -EBUSY;
611         desc->txd.flags = flags;
612
613         return &first->txd;
614
615 err_desc_get:
616         dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
617         pdc_desc_put(pd_chan, first);
618         return NULL;
619 }
620
621 static int pd_device_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
622                              unsigned long arg)
623 {
624         struct pch_dma_chan *pd_chan = to_pd_chan(chan);
625         struct pch_dma_desc *desc, *_d;
626         LIST_HEAD(list);
627
628         if (cmd != DMA_TERMINATE_ALL)
629                 return -ENXIO;
630
631         spin_lock_bh(&pd_chan->lock);
632
633         pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
634
635         list_splice_init(&pd_chan->active_list, &list);
636         list_splice_init(&pd_chan->queue, &list);
637
638         list_for_each_entry_safe(desc, _d, &list, desc_node)
639                 pdc_chain_complete(pd_chan, desc);
640
641         spin_unlock_bh(&pd_chan->lock);
642
643         return 0;
644 }
645
646 static void pdc_tasklet(unsigned long data)
647 {
648         struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
649         unsigned long flags;
650
651         if (!pdc_is_idle(pd_chan)) {
652                 dev_err(chan2dev(&pd_chan->chan),
653                         "BUG: handle non-idle channel in tasklet\n");
654                 return;
655         }
656
657         spin_lock_irqsave(&pd_chan->lock, flags);
658         if (test_and_clear_bit(0, &pd_chan->err_status))
659                 pdc_handle_error(pd_chan);
660         else
661                 pdc_advance_work(pd_chan);
662         spin_unlock_irqrestore(&pd_chan->lock, flags);
663 }
664
665 static irqreturn_t pd_irq(int irq, void *devid)
666 {
667         struct pch_dma *pd = (struct pch_dma *)devid;
668         struct pch_dma_chan *pd_chan;
669         u32 sts0;
670         int i;
671         int ret = IRQ_NONE;
672
673         sts0 = dma_readl(pd, STS0);
674
675         dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
676
677         for (i = 0; i < pd->dma.chancnt; i++) {
678                 pd_chan = &pd->channels[i];
679
680                 if (sts0 & DMA_STATUS_IRQ(i)) {
681                         if (sts0 & DMA_STATUS_ERR(i))
682                                 set_bit(0, &pd_chan->err_status);
683
684                         tasklet_schedule(&pd_chan->tasklet);
685                         ret = IRQ_HANDLED;
686                 }
687
688         }
689
690         /* clear interrupt bits in status register */
691         dma_writel(pd, STS0, sts0);
692
693         return ret;
694 }
695
696 static void pch_dma_save_regs(struct pch_dma *pd)
697 {
698         struct pch_dma_chan *pd_chan;
699         struct dma_chan *chan, *_c;
700         int i = 0;
701
702         pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
703         pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
704         pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
705
706         list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
707                 pd_chan = to_pd_chan(chan);
708
709                 pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
710                 pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
711                 pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
712                 pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
713
714                 i++;
715         }
716 }
717
718 static void pch_dma_restore_regs(struct pch_dma *pd)
719 {
720         struct pch_dma_chan *pd_chan;
721         struct dma_chan *chan, *_c;
722         int i = 0;
723
724         dma_writel(pd, CTL0, pd->regs.dma_ctl0);
725         dma_writel(pd, CTL1, pd->regs.dma_ctl1);
726         dma_writel(pd, CTL2, pd->regs.dma_ctl2);
727
728         list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
729                 pd_chan = to_pd_chan(chan);
730
731                 channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
732                 channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
733                 channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
734                 channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
735
736                 i++;
737         }
738 }
739
740 static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
741 {
742         struct pch_dma *pd = pci_get_drvdata(pdev);
743
744         if (pd)
745                 pch_dma_save_regs(pd);
746
747         pci_save_state(pdev);
748         pci_disable_device(pdev);
749         pci_set_power_state(pdev, pci_choose_state(pdev, state));
750
751         return 0;
752 }
753
754 static int pch_dma_resume(struct pci_dev *pdev)
755 {
756         struct pch_dma *pd = pci_get_drvdata(pdev);
757         int err;
758
759         pci_set_power_state(pdev, PCI_D0);
760         pci_restore_state(pdev);
761
762         err = pci_enable_device(pdev);
763         if (err) {
764                 dev_dbg(&pdev->dev, "failed to enable device\n");
765                 return err;
766         }
767
768         if (pd)
769                 pch_dma_restore_regs(pd);
770
771         return 0;
772 }
773
774 static int __devinit pch_dma_probe(struct pci_dev *pdev,
775                                    const struct pci_device_id *id)
776 {
777         struct pch_dma *pd;
778         struct pch_dma_regs *regs;
779         unsigned int nr_channels;
780         int err;
781         int i;
782
783         nr_channels = id->driver_data;
784         pd = kzalloc(sizeof(struct pch_dma)+
785                 sizeof(struct pch_dma_chan) * nr_channels, GFP_KERNEL);
786         if (!pd)
787                 return -ENOMEM;
788
789         pci_set_drvdata(pdev, pd);
790
791         err = pci_enable_device(pdev);
792         if (err) {
793                 dev_err(&pdev->dev, "Cannot enable PCI device\n");
794                 goto err_free_mem;
795         }
796
797         if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
798                 dev_err(&pdev->dev, "Cannot find proper base address\n");
799                 goto err_disable_pdev;
800         }
801
802         err = pci_request_regions(pdev, DRV_NAME);
803         if (err) {
804                 dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
805                 goto err_disable_pdev;
806         }
807
808         err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
809         if (err) {
810                 dev_err(&pdev->dev, "Cannot set proper DMA config\n");
811                 goto err_free_res;
812         }
813
814         regs = pd->membase = pci_iomap(pdev, 1, 0);
815         if (!pd->membase) {
816                 dev_err(&pdev->dev, "Cannot map MMIO registers\n");
817                 err = -ENOMEM;
818                 goto err_free_res;
819         }
820
821         pci_set_master(pdev);
822
823         err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
824         if (err) {
825                 dev_err(&pdev->dev, "Failed to request IRQ\n");
826                 goto err_iounmap;
827         }
828
829         pd->pool = pci_pool_create("pch_dma_desc_pool", pdev,
830                                    sizeof(struct pch_dma_desc), 4, 0);
831         if (!pd->pool) {
832                 dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
833                 err = -ENOMEM;
834                 goto err_free_irq;
835         }
836
837         pd->dma.dev = &pdev->dev;
838         pd->dma.chancnt = nr_channels;
839
840         INIT_LIST_HEAD(&pd->dma.channels);
841
842         for (i = 0; i < nr_channels; i++) {
843                 struct pch_dma_chan *pd_chan = &pd->channels[i];
844
845                 pd_chan->chan.device = &pd->dma;
846                 pd_chan->chan.cookie = 1;
847                 pd_chan->chan.chan_id = i;
848
849                 pd_chan->membase = &regs->desc[i];
850
851                 pd_chan->dir = (i % 2) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
852
853                 spin_lock_init(&pd_chan->lock);
854
855                 INIT_LIST_HEAD(&pd_chan->active_list);
856                 INIT_LIST_HEAD(&pd_chan->queue);
857                 INIT_LIST_HEAD(&pd_chan->free_list);
858
859                 tasklet_init(&pd_chan->tasklet, pdc_tasklet,
860                              (unsigned long)pd_chan);
861                 list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
862         }
863
864         dma_cap_zero(pd->dma.cap_mask);
865         dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
866         dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
867
868         pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
869         pd->dma.device_free_chan_resources = pd_free_chan_resources;
870         pd->dma.device_tx_status = pd_tx_status;
871         pd->dma.device_issue_pending = pd_issue_pending;
872         pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
873         pd->dma.device_control = pd_device_control;
874
875         err = dma_async_device_register(&pd->dma);
876         if (err) {
877                 dev_err(&pdev->dev, "Failed to register DMA device\n");
878                 goto err_free_pool;
879         }
880
881         return 0;
882
883 err_free_pool:
884         pci_pool_destroy(pd->pool);
885 err_free_irq:
886         free_irq(pdev->irq, pd);
887 err_iounmap:
888         pci_iounmap(pdev, pd->membase);
889 err_free_res:
890         pci_release_regions(pdev);
891 err_disable_pdev:
892         pci_disable_device(pdev);
893 err_free_mem:
894         return err;
895 }
896
897 static void __devexit pch_dma_remove(struct pci_dev *pdev)
898 {
899         struct pch_dma *pd = pci_get_drvdata(pdev);
900         struct pch_dma_chan *pd_chan;
901         struct dma_chan *chan, *_c;
902
903         if (pd) {
904                 dma_async_device_unregister(&pd->dma);
905
906                 list_for_each_entry_safe(chan, _c, &pd->dma.channels,
907                                          device_node) {
908                         pd_chan = to_pd_chan(chan);
909
910                         tasklet_disable(&pd_chan->tasklet);
911                         tasklet_kill(&pd_chan->tasklet);
912                 }
913
914                 pci_pool_destroy(pd->pool);
915                 free_irq(pdev->irq, pd);
916                 pci_iounmap(pdev, pd->membase);
917                 pci_release_regions(pdev);
918                 pci_disable_device(pdev);
919                 kfree(pd);
920         }
921 }
922
923 /* PCI Device ID of DMA device */
924 #define PCI_VENDOR_ID_ROHM             0x10DB
925 #define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH        0x8810
926 #define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH        0x8815
927 #define PCI_DEVICE_ID_ML7213_DMA1_8CH   0x8026
928 #define PCI_DEVICE_ID_ML7213_DMA2_8CH   0x802B
929 #define PCI_DEVICE_ID_ML7213_DMA3_4CH   0x8034
930
931 static const struct pci_device_id pch_dma_id_table[] = {
932         { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
933         { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
934         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
935         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
936         { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
937         { 0, },
938 };
939
940 static struct pci_driver pch_dma_driver = {
941         .name           = DRV_NAME,
942         .id_table       = pch_dma_id_table,
943         .probe          = pch_dma_probe,
944         .remove         = __devexit_p(pch_dma_remove),
945 #ifdef CONFIG_PM
946         .suspend        = pch_dma_suspend,
947         .resume         = pch_dma_resume,
948 #endif
949 };
950
951 static int __init pch_dma_init(void)
952 {
953         return pci_register_driver(&pch_dma_driver);
954 }
955
956 static void __exit pch_dma_exit(void)
957 {
958         pci_unregister_driver(&pch_dma_driver);
959 }
960
961 module_init(pch_dma_init);
962 module_exit(pch_dma_exit);
963
964 MODULE_DESCRIPTION("Intel EG20T PCH / OKI SEMICONDUCTOR ML7213 IOH "
965                    "DMA controller driver");
966 MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
967 MODULE_LICENSE("GPL v2");