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Linux 3.3-rc6
[linux/fpc-iii.git] / drivers / dma / pch_dma.c
blob823f58179f9d46a8a169dbbaf7551b1d91ec5f28
1 /*
2 * Topcliff PCH DMA controller driver
3 * Copyright (c) 2010 Intel Corporation
4 * Copyright (C) 2011 LAPIS 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_STATUS0_ERR(x) (0x1 << ((x) + 8))
49 #define DMA_STATUS2_ERR(x) (0x1 << (x))
50
51 #define DMA_DESC_WIDTH_SHIFT_BITS 12
52 #define DMA_DESC_WIDTH_1_BYTE (0x3 << DMA_DESC_WIDTH_SHIFT_BITS)
53 #define DMA_DESC_WIDTH_2_BYTES (0x2 << DMA_DESC_WIDTH_SHIFT_BITS)
54 #define DMA_DESC_WIDTH_4_BYTES (0x0 << DMA_DESC_WIDTH_SHIFT_BITS)
55 #define DMA_DESC_MAX_COUNT_1_BYTE 0x3FF
56 #define DMA_DESC_MAX_COUNT_2_BYTES 0x3FF
57 #define DMA_DESC_MAX_COUNT_4_BYTES 0x7FF
58 #define DMA_DESC_END_WITHOUT_IRQ 0x0
59 #define DMA_DESC_END_WITH_IRQ 0x1
60 #define DMA_DESC_FOLLOW_WITHOUT_IRQ 0x2
61 #define DMA_DESC_FOLLOW_WITH_IRQ 0x3
62
63 #define MAX_CHAN_NR 12
64
65 #define DMA_MASK_CTL0_MODE 0x33333333
66 #define DMA_MASK_CTL2_MODE 0x00003333
67
68 static unsigned int init_nr_desc_per_channel = 64;
69 module_param(init_nr_desc_per_channel, uint, 0644);
70 MODULE_PARM_DESC(init_nr_desc_per_channel,
71 "initial descriptors per channel (default: 64)");
72
73 struct pch_dma_desc_regs {
74 u32 dev_addr;
75 u32 mem_addr;
76 u32 size;
77 u32 next;
78 };
79
80 struct pch_dma_regs {
81 u32 dma_ctl0;
82 u32 dma_ctl1;
83 u32 dma_ctl2;
84 u32 dma_ctl3;
85 u32 dma_sts0;
86 u32 dma_sts1;
87 u32 dma_sts2;
88 u32 reserved3;
89 struct pch_dma_desc_regs desc[MAX_CHAN_NR];
90 };
91
92 struct pch_dma_desc {
93 struct pch_dma_desc_regs regs;
94 struct dma_async_tx_descriptor txd;
95 struct list_head desc_node;
96 struct list_head tx_list;
97 };
98
99 struct pch_dma_chan {
100 struct dma_chan chan;
101 void __iomem *membase;
102 enum dma_transfer_direction dir;
103 struct tasklet_struct tasklet;
104 unsigned long err_status;
105
106 spinlock_t lock;
107
108 dma_cookie_t completed_cookie;
109 struct list_head active_list;
110 struct list_head queue;
111 struct list_head free_list;
112 unsigned int descs_allocated;
113 };
114
115 #define PDC_DEV_ADDR 0x00
116 #define PDC_MEM_ADDR 0x04
117 #define PDC_SIZE 0x08
118 #define PDC_NEXT 0x0C
119
120 #define channel_readl(pdc, name) \
121 readl((pdc)->membase + PDC_##name)
122 #define channel_writel(pdc, name, val) \
123 writel((val), (pdc)->membase + PDC_##name)
124
125 struct pch_dma {
126 struct dma_device dma;
127 void __iomem *membase;
128 struct pci_pool *pool;
129 struct pch_dma_regs regs;
130 struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
131 struct pch_dma_chan channels[MAX_CHAN_NR];
132 };
133
134 #define PCH_DMA_CTL0 0x00
135 #define PCH_DMA_CTL1 0x04
136 #define PCH_DMA_CTL2 0x08
137 #define PCH_DMA_CTL3 0x0C
138 #define PCH_DMA_STS0 0x10
139 #define PCH_DMA_STS1 0x14
140 #define PCH_DMA_STS2 0x18
141
142 #define dma_readl(pd, name) \
143 readl((pd)->membase + PCH_DMA_##name)
144 #define dma_writel(pd, name, val) \
145 writel((val), (pd)->membase + PCH_DMA_##name)
146
147 static inline
148 struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
149 {
150 return container_of(txd, struct pch_dma_desc, txd);
151 }
152
153 static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
154 {
155 return container_of(chan, struct pch_dma_chan, chan);
156 }
157
158 static inline struct pch_dma *to_pd(struct dma_device *ddev)
159 {
160 return container_of(ddev, struct pch_dma, dma);
161 }
162
163 static inline struct device *chan2dev(struct dma_chan *chan)
164 {
165 return &chan->dev->device;
166 }
167
168 static inline struct device *chan2parent(struct dma_chan *chan)
169 {
170 return chan->dev->device.parent;
171 }
172
173 static inline
174 struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
175 {
176 return list_first_entry(&pd_chan->active_list,
177 struct pch_dma_desc, desc_node);
178 }
179
180 static inline
181 struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
182 {
183 return list_first_entry(&pd_chan->queue,
184 struct pch_dma_desc, desc_node);
185 }
186
187 static void pdc_enable_irq(struct dma_chan *chan, int enable)
188 {
189 struct pch_dma *pd = to_pd(chan->device);
190 u32 val;
191 int pos;
192
193 if (chan->chan_id < 8)
194 pos = chan->chan_id;
195 else
196 pos = chan->chan_id + 8;
197
198 val = dma_readl(pd, CTL2);
199
200 if (enable)
201 val |= 0x1 << pos;
202 else
203 val &= ~(0x1 << pos);
204
205 dma_writel(pd, CTL2, val);
206
207 dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
208 chan->chan_id, val);
209 }
210
211 static void pdc_set_dir(struct dma_chan *chan)
212 {
213 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
214 struct pch_dma *pd = to_pd(chan->device);
215 u32 val;
216 u32 mask_mode;
217 u32 mask_ctl;
218
219 if (chan->chan_id < 8) {
220 val = dma_readl(pd, CTL0);
221
222 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
223 (DMA_CTL0_BITS_PER_CH * chan->chan_id);
224 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
225 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
226 val &= mask_mode;
227 if (pd_chan->dir == DMA_MEM_TO_DEV)
228 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
229 DMA_CTL0_DIR_SHIFT_BITS);
230 else
231 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
232 DMA_CTL0_DIR_SHIFT_BITS));
233
234 val |= mask_ctl;
235 dma_writel(pd, CTL0, val);
236 } else {
237 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
238 val = dma_readl(pd, CTL3);
239
240 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
241 (DMA_CTL0_BITS_PER_CH * ch);
242 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
243 (DMA_CTL0_BITS_PER_CH * ch));
244 val &= mask_mode;
245 if (pd_chan->dir == DMA_MEM_TO_DEV)
246 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +
247 DMA_CTL0_DIR_SHIFT_BITS);
248 else
249 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +
250 DMA_CTL0_DIR_SHIFT_BITS));
251 val |= mask_ctl;
252 dma_writel(pd, CTL3, val);
253 }
254
255 dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
256 chan->chan_id, val);
257 }
258
259 static void pdc_set_mode(struct dma_chan *chan, u32 mode)
260 {
261 struct pch_dma *pd = to_pd(chan->device);
262 u32 val;
263 u32 mask_ctl;
264 u32 mask_dir;
265
266 if (chan->chan_id < 8) {
267 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
268 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
269 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\
270 DMA_CTL0_DIR_SHIFT_BITS);
271 val = dma_readl(pd, CTL0);
272 val &= mask_dir;
273 val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
274 val |= mask_ctl;
275 dma_writel(pd, CTL0, val);
276 } else {
277 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
278 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
279 (DMA_CTL0_BITS_PER_CH * ch));
280 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\
281 DMA_CTL0_DIR_SHIFT_BITS);
282 val = dma_readl(pd, CTL3);
283 val &= mask_dir;
284 val |= mode << (DMA_CTL0_BITS_PER_CH * ch);
285 val |= mask_ctl;
286 dma_writel(pd, CTL3, val);
287 }
288
289 dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
290 chan->chan_id, val);
291 }
292
293 static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)
294 {
295 struct pch_dma *pd = to_pd(pd_chan->chan.device);
296 u32 val;
297
298 val = dma_readl(pd, STS0);
299 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
300 DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
301 }
302
303 static u32 pdc_get_status2(struct pch_dma_chan *pd_chan)
304 {
305 struct pch_dma *pd = to_pd(pd_chan->chan.device);
306 u32 val;
307
308 val = dma_readl(pd, STS2);
309 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
310 DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));
311 }
312
313 static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
314 {
315 u32 sts;
316
317 if (pd_chan->chan.chan_id < 8)
318 sts = pdc_get_status0(pd_chan);
319 else
320 sts = pdc_get_status2(pd_chan);
321
322
323 if (sts == DMA_STATUS_IDLE)
324 return true;
325 else
326 return false;
327 }
328
329 static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
330 {
331 if (!pdc_is_idle(pd_chan)) {
332 dev_err(chan2dev(&pd_chan->chan),
333 "BUG: Attempt to start non-idle channel\n");
334 return;
335 }
336
337 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
338 pd_chan->chan.chan_id, desc->regs.dev_addr);
339 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
340 pd_chan->chan.chan_id, desc->regs.mem_addr);
341 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
342 pd_chan->chan.chan_id, desc->regs.size);
343 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
344 pd_chan->chan.chan_id, desc->regs.next);
345
346 if (list_empty(&desc->tx_list)) {
347 channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
348 channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
349 channel_writel(pd_chan, SIZE, desc->regs.size);
350 channel_writel(pd_chan, NEXT, desc->regs.next);
351 pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
352 } else {
353 channel_writel(pd_chan, NEXT, desc->txd.phys);
354 pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
355 }
356 }
357
358 static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
359 struct pch_dma_desc *desc)
360 {
361 struct dma_async_tx_descriptor *txd = &desc->txd;
362 dma_async_tx_callback callback = txd->callback;
363 void *param = txd->callback_param;
364
365 list_splice_init(&desc->tx_list, &pd_chan->free_list);
366 list_move(&desc->desc_node, &pd_chan->free_list);
367
368 if (callback)
369 callback(param);
370 }
371
372 static void pdc_complete_all(struct pch_dma_chan *pd_chan)
373 {
374 struct pch_dma_desc *desc, *_d;
375 LIST_HEAD(list);
376
377 BUG_ON(!pdc_is_idle(pd_chan));
378
379 if (!list_empty(&pd_chan->queue))
380 pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
381
382 list_splice_init(&pd_chan->active_list, &list);
383 list_splice_init(&pd_chan->queue, &pd_chan->active_list);
384
385 list_for_each_entry_safe(desc, _d, &list, desc_node)
386 pdc_chain_complete(pd_chan, desc);
387 }
388
389 static void pdc_handle_error(struct pch_dma_chan *pd_chan)
390 {
391 struct pch_dma_desc *bad_desc;
392
393 bad_desc = pdc_first_active(pd_chan);
394 list_del(&bad_desc->desc_node);
395
396 list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
397
398 if (!list_empty(&pd_chan->active_list))
399 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
400
401 dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
402 dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
403 bad_desc->txd.cookie);
404
405 pdc_chain_complete(pd_chan, bad_desc);
406 }
407
408 static void pdc_advance_work(struct pch_dma_chan *pd_chan)
409 {
410 if (list_empty(&pd_chan->active_list) ||
411 list_is_singular(&pd_chan->active_list)) {
412 pdc_complete_all(pd_chan);
413 } else {
414 pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
415 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
416 }
417 }
418
419 static dma_cookie_t pdc_assign_cookie(struct pch_dma_chan *pd_chan,
420 struct pch_dma_desc *desc)
421 {
422 dma_cookie_t cookie = pd_chan->chan.cookie;
423
424 if (++cookie < 0)
425 cookie = 1;
426
427 pd_chan->chan.cookie = cookie;
428 desc->txd.cookie = cookie;
429
430 return cookie;
431 }
432
433 static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
434 {
435 struct pch_dma_desc *desc = to_pd_desc(txd);
436 struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
437 dma_cookie_t cookie;
438
439 spin_lock(&pd_chan->lock);
440 cookie = pdc_assign_cookie(pd_chan, desc);
441
442 if (list_empty(&pd_chan->active_list)) {
443 list_add_tail(&desc->desc_node, &pd_chan->active_list);
444 pdc_dostart(pd_chan, desc);
445 } else {
446 list_add_tail(&desc->desc_node, &pd_chan->queue);
447 }
448
449 spin_unlock(&pd_chan->lock);
450 return 0;
451 }
452
453 static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
454 {
455 struct pch_dma_desc *desc = NULL;
456 struct pch_dma *pd = to_pd(chan->device);
457 dma_addr_t addr;
458
459 desc = pci_pool_alloc(pd->pool, flags, &addr);
460 if (desc) {
461 memset(desc, 0, sizeof(struct pch_dma_desc));
462 INIT_LIST_HEAD(&desc->tx_list);
463 dma_async_tx_descriptor_init(&desc->txd, chan);
464 desc->txd.tx_submit = pd_tx_submit;
465 desc->txd.flags = DMA_CTRL_ACK;
466 desc->txd.phys = addr;
467 }
468
469 return desc;
470 }
471
472 static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
473 {
474 struct pch_dma_desc *desc, *_d;
475 struct pch_dma_desc *ret = NULL;
476 int i = 0;
477
478 spin_lock(&pd_chan->lock);
479 list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
480 i++;
481 if (async_tx_test_ack(&desc->txd)) {
482 list_del(&desc->desc_node);
483 ret = desc;
484 break;
485 }
486 dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
487 }
488 spin_unlock(&pd_chan->lock);
489 dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
490
491 if (!ret) {
492 ret = pdc_alloc_desc(&pd_chan->chan, GFP_NOIO);
493 if (ret) {
494 spin_lock(&pd_chan->lock);
495 pd_chan->descs_allocated++;
496 spin_unlock(&pd_chan->lock);
497 } else {
498 dev_err(chan2dev(&pd_chan->chan),
499 "failed to alloc desc\n");
500 }
501 }
502
503 return ret;
504 }
505
506 static void pdc_desc_put(struct pch_dma_chan *pd_chan,
507 struct pch_dma_desc *desc)
508 {
509 if (desc) {
510 spin_lock(&pd_chan->lock);
511 list_splice_init(&desc->tx_list, &pd_chan->free_list);
512 list_add(&desc->desc_node, &pd_chan->free_list);
513 spin_unlock(&pd_chan->lock);
514 }
515 }
516
517 static int pd_alloc_chan_resources(struct dma_chan *chan)
518 {
519 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
520 struct pch_dma_desc *desc;
521 LIST_HEAD(tmp_list);
522 int i;
523
524 if (!pdc_is_idle(pd_chan)) {
525 dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
526 return -EIO;
527 }
528
529 if (!list_empty(&pd_chan->free_list))
530 return pd_chan->descs_allocated;
531
532 for (i = 0; i < init_nr_desc_per_channel; i++) {
533 desc = pdc_alloc_desc(chan, GFP_KERNEL);
534
535 if (!desc) {
536 dev_warn(chan2dev(chan),
537 "Only allocated %d initial descriptors\n", i);
538 break;
539 }
540
541 list_add_tail(&desc->desc_node, &tmp_list);
542 }
543
544 spin_lock_irq(&pd_chan->lock);
545 list_splice(&tmp_list, &pd_chan->free_list);
546 pd_chan->descs_allocated = i;
547 pd_chan->completed_cookie = chan->cookie = 1;
548 spin_unlock_irq(&pd_chan->lock);
549
550 pdc_enable_irq(chan, 1);
551
552 return pd_chan->descs_allocated;
553 }
554
555 static void pd_free_chan_resources(struct dma_chan *chan)
556 {
557 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
558 struct pch_dma *pd = to_pd(chan->device);
559 struct pch_dma_desc *desc, *_d;
560 LIST_HEAD(tmp_list);
561
562 BUG_ON(!pdc_is_idle(pd_chan));
563 BUG_ON(!list_empty(&pd_chan->active_list));
564 BUG_ON(!list_empty(&pd_chan->queue));
565
566 spin_lock_irq(&pd_chan->lock);
567 list_splice_init(&pd_chan->free_list, &tmp_list);
568 pd_chan->descs_allocated = 0;
569 spin_unlock_irq(&pd_chan->lock);
570
571 list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
572 pci_pool_free(pd->pool, desc, desc->txd.phys);
573
574 pdc_enable_irq(chan, 0);
575 }
576
577 static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
578 struct dma_tx_state *txstate)
579 {
580 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
581 dma_cookie_t last_used;
582 dma_cookie_t last_completed;
583 int ret;
584
585 spin_lock_irq(&pd_chan->lock);
586 last_completed = pd_chan->completed_cookie;
587 last_used = chan->cookie;
588 spin_unlock_irq(&pd_chan->lock);
589
590 ret = dma_async_is_complete(cookie, last_completed, last_used);
591
592 dma_set_tx_state(txstate, last_completed, last_used, 0);
593
594 return ret;
595 }
596
597 static void pd_issue_pending(struct dma_chan *chan)
598 {
599 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
600
601 if (pdc_is_idle(pd_chan)) {
602 spin_lock(&pd_chan->lock);
603 pdc_advance_work(pd_chan);
604 spin_unlock(&pd_chan->lock);
605 }
606 }
607
608 static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,
609 struct scatterlist *sgl, unsigned int sg_len,
610 enum dma_transfer_direction direction, unsigned long flags)
611 {
612 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
613 struct pch_dma_slave *pd_slave = chan->private;
614 struct pch_dma_desc *first = NULL;
615 struct pch_dma_desc *prev = NULL;
616 struct pch_dma_desc *desc = NULL;
617 struct scatterlist *sg;
618 dma_addr_t reg;
619 int i;
620
621 if (unlikely(!sg_len)) {
622 dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
623 return NULL;
624 }
625
626 if (direction == DMA_DEV_TO_MEM)
627 reg = pd_slave->rx_reg;
628 else if (direction == DMA_MEM_TO_DEV)
629 reg = pd_slave->tx_reg;
630 else
631 return NULL;
632
633 pd_chan->dir = direction;
634 pdc_set_dir(chan);
635
636 for_each_sg(sgl, sg, sg_len, i) {
637 desc = pdc_desc_get(pd_chan);
638
639 if (!desc)
640 goto err_desc_get;
641
642 desc->regs.dev_addr = reg;
643 desc->regs.mem_addr = sg_phys(sg);
644 desc->regs.size = sg_dma_len(sg);
645 desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
646
647 switch (pd_slave->width) {
648 case PCH_DMA_WIDTH_1_BYTE:
649 if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
650 goto err_desc_get;
651 desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
652 break;
653 case PCH_DMA_WIDTH_2_BYTES:
654 if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
655 goto err_desc_get;
656 desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
657 break;
658 case PCH_DMA_WIDTH_4_BYTES:
659 if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
660 goto err_desc_get;
661 desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
662 break;
663 default:
664 goto err_desc_get;
665 }
666
667 if (!first) {
668 first = desc;
669 } else {
670 prev->regs.next |= desc->txd.phys;
671 list_add_tail(&desc->desc_node, &first->tx_list);
672 }
673
674 prev = desc;
675 }
676
677 if (flags & DMA_PREP_INTERRUPT)
678 desc->regs.next = DMA_DESC_END_WITH_IRQ;
679 else
680 desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
681
682 first->txd.cookie = -EBUSY;
683 desc->txd.flags = flags;
684
685 return &first->txd;
686
687 err_desc_get:
688 dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
689 pdc_desc_put(pd_chan, first);
690 return NULL;
691 }
692
693 static int pd_device_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
694 unsigned long arg)
695 {
696 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
697 struct pch_dma_desc *desc, *_d;
698 LIST_HEAD(list);
699
700 if (cmd != DMA_TERMINATE_ALL)
701 return -ENXIO;
702
703 spin_lock_irq(&pd_chan->lock);
704
705 pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
706
707 list_splice_init(&pd_chan->active_list, &list);
708 list_splice_init(&pd_chan->queue, &list);
709
710 list_for_each_entry_safe(desc, _d, &list, desc_node)
711 pdc_chain_complete(pd_chan, desc);
712
713 spin_unlock_irq(&pd_chan->lock);
714
715 return 0;
716 }
717
718 static void pdc_tasklet(unsigned long data)
719 {
720 struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
721 unsigned long flags;
722
723 if (!pdc_is_idle(pd_chan)) {
724 dev_err(chan2dev(&pd_chan->chan),
725 "BUG: handle non-idle channel in tasklet\n");
726 return;
727 }
728
729 spin_lock_irqsave(&pd_chan->lock, flags);
730 if (test_and_clear_bit(0, &pd_chan->err_status))
731 pdc_handle_error(pd_chan);
732 else
733 pdc_advance_work(pd_chan);
734 spin_unlock_irqrestore(&pd_chan->lock, flags);
735 }
736
737 static irqreturn_t pd_irq(int irq, void *devid)
738 {
739 struct pch_dma *pd = (struct pch_dma *)devid;
740 struct pch_dma_chan *pd_chan;
741 u32 sts0;
742 u32 sts2;
743 int i;
744 int ret0 = IRQ_NONE;
745 int ret2 = IRQ_NONE;
746
747 sts0 = dma_readl(pd, STS0);
748 sts2 = dma_readl(pd, STS2);
749
750 dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
751
752 for (i = 0; i < pd->dma.chancnt; i++) {
753 pd_chan = &pd->channels[i];
754
755 if (i < 8) {
756 if (sts0 & DMA_STATUS_IRQ(i)) {
757 if (sts0 & DMA_STATUS0_ERR(i))
758 set_bit(0, &pd_chan->err_status);
759
760 tasklet_schedule(&pd_chan->tasklet);
761 ret0 = IRQ_HANDLED;
762 }
763 } else {
764 if (sts2 & DMA_STATUS_IRQ(i - 8)) {
765 if (sts2 & DMA_STATUS2_ERR(i))
766 set_bit(0, &pd_chan->err_status);
767
768 tasklet_schedule(&pd_chan->tasklet);
769 ret2 = IRQ_HANDLED;
770 }
771 }
772 }
773
774 /* clear interrupt bits in status register */
775 if (ret0)
776 dma_writel(pd, STS0, sts0);
777 if (ret2)
778 dma_writel(pd, STS2, sts2);
779
780 return ret0 | ret2;
781 }
782
783 #ifdef CONFIG_PM
784 static void pch_dma_save_regs(struct pch_dma *pd)
785 {
786 struct pch_dma_chan *pd_chan;
787 struct dma_chan *chan, *_c;
788 int i = 0;
789
790 pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
791 pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
792 pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
793 pd->regs.dma_ctl3 = dma_readl(pd, CTL3);
794
795 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
796 pd_chan = to_pd_chan(chan);
797
798 pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
799 pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
800 pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
801 pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
802
803 i++;
804 }
805 }
806
807 static void pch_dma_restore_regs(struct pch_dma *pd)
808 {
809 struct pch_dma_chan *pd_chan;
810 struct dma_chan *chan, *_c;
811 int i = 0;
812
813 dma_writel(pd, CTL0, pd->regs.dma_ctl0);
814 dma_writel(pd, CTL1, pd->regs.dma_ctl1);
815 dma_writel(pd, CTL2, pd->regs.dma_ctl2);
816 dma_writel(pd, CTL3, pd->regs.dma_ctl3);
817
818 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
819 pd_chan = to_pd_chan(chan);
820
821 channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
822 channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
823 channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
824 channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
825
826 i++;
827 }
828 }
829
830 static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
831 {
832 struct pch_dma *pd = pci_get_drvdata(pdev);
833
834 if (pd)
835 pch_dma_save_regs(pd);
836
837 pci_save_state(pdev);
838 pci_disable_device(pdev);
839 pci_set_power_state(pdev, pci_choose_state(pdev, state));
840
841 return 0;
842 }
843
844 static int pch_dma_resume(struct pci_dev *pdev)
845 {
846 struct pch_dma *pd = pci_get_drvdata(pdev);
847 int err;
848
849 pci_set_power_state(pdev, PCI_D0);
850 pci_restore_state(pdev);
851
852 err = pci_enable_device(pdev);
853 if (err) {
854 dev_dbg(&pdev->dev, "failed to enable device\n");
855 return err;
856 }
857
858 if (pd)
859 pch_dma_restore_regs(pd);
860
861 return 0;
862 }
863 #endif
864
865 static int __devinit pch_dma_probe(struct pci_dev *pdev,
866 const struct pci_device_id *id)
867 {
868 struct pch_dma *pd;
869 struct pch_dma_regs *regs;
870 unsigned int nr_channels;
871 int err;
872 int i;
873
874 nr_channels = id->driver_data;
875 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
876 if (!pd)
877 return -ENOMEM;
878
879 pci_set_drvdata(pdev, pd);
880
881 err = pci_enable_device(pdev);
882 if (err) {
883 dev_err(&pdev->dev, "Cannot enable PCI device\n");
884 goto err_free_mem;
885 }
886
887 if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
888 dev_err(&pdev->dev, "Cannot find proper base address\n");
889 goto err_disable_pdev;
890 }
891
892 err = pci_request_regions(pdev, DRV_NAME);
893 if (err) {
894 dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
895 goto err_disable_pdev;
896 }
897
898 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
899 if (err) {
900 dev_err(&pdev->dev, "Cannot set proper DMA config\n");
901 goto err_free_res;
902 }
903
904 regs = pd->membase = pci_iomap(pdev, 1, 0);
905 if (!pd->membase) {
906 dev_err(&pdev->dev, "Cannot map MMIO registers\n");
907 err = -ENOMEM;
908 goto err_free_res;
909 }
910
911 pci_set_master(pdev);
912
913 err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
914 if (err) {
915 dev_err(&pdev->dev, "Failed to request IRQ\n");
916 goto err_iounmap;
917 }
918
919 pd->pool = pci_pool_create("pch_dma_desc_pool", pdev,
920 sizeof(struct pch_dma_desc), 4, 0);
921 if (!pd->pool) {
922 dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
923 err = -ENOMEM;
924 goto err_free_irq;
925 }
926
927 pd->dma.dev = &pdev->dev;
928
929 INIT_LIST_HEAD(&pd->dma.channels);
930
931 for (i = 0; i < nr_channels; i++) {
932 struct pch_dma_chan *pd_chan = &pd->channels[i];
933
934 pd_chan->chan.device = &pd->dma;
935 pd_chan->chan.cookie = 1;
936
937 pd_chan->membase = &regs->desc[i];
938
939 spin_lock_init(&pd_chan->lock);
940
941 INIT_LIST_HEAD(&pd_chan->active_list);
942 INIT_LIST_HEAD(&pd_chan->queue);
943 INIT_LIST_HEAD(&pd_chan->free_list);
944
945 tasklet_init(&pd_chan->tasklet, pdc_tasklet,
946 (unsigned long)pd_chan);
947 list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
948 }
949
950 dma_cap_zero(pd->dma.cap_mask);
951 dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
952 dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
953
954 pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
955 pd->dma.device_free_chan_resources = pd_free_chan_resources;
956 pd->dma.device_tx_status = pd_tx_status;
957 pd->dma.device_issue_pending = pd_issue_pending;
958 pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
959 pd->dma.device_control = pd_device_control;
960
961 err = dma_async_device_register(&pd->dma);
962 if (err) {
963 dev_err(&pdev->dev, "Failed to register DMA device\n");
964 goto err_free_pool;
965 }
966
967 return 0;
968
969 err_free_pool:
970 pci_pool_destroy(pd->pool);
971 err_free_irq:
972 free_irq(pdev->irq, pd);
973 err_iounmap:
974 pci_iounmap(pdev, pd->membase);
975 err_free_res:
976 pci_release_regions(pdev);
977 err_disable_pdev:
978 pci_disable_device(pdev);
979 err_free_mem:
980 return err;
981 }
982
983 static void __devexit pch_dma_remove(struct pci_dev *pdev)
984 {
985 struct pch_dma *pd = pci_get_drvdata(pdev);
986 struct pch_dma_chan *pd_chan;
987 struct dma_chan *chan, *_c;
988
989 if (pd) {
990 dma_async_device_unregister(&pd->dma);
991
992 list_for_each_entry_safe(chan, _c, &pd->dma.channels,
993 device_node) {
994 pd_chan = to_pd_chan(chan);
995
996 tasklet_disable(&pd_chan->tasklet);
997 tasklet_kill(&pd_chan->tasklet);
998 }
999
1000 pci_pool_destroy(pd->pool);
1001 free_irq(pdev->irq, pd);
1002 pci_iounmap(pdev, pd->membase);
1003 pci_release_regions(pdev);
1004 pci_disable_device(pdev);
1005 kfree(pd);
1006 }
1007 }
1008
1009 /* PCI Device ID of DMA device */
1010 #define PCI_VENDOR_ID_ROHM 0x10DB
1011 #define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810
1012 #define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815
1013 #define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026
1014 #define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B
1015 #define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034
1016 #define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032
1017 #define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B
1018 #define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E
1019 #define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017
1020 #define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B
1021 #define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810
1022 #define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815
1023
1024 DEFINE_PCI_DEVICE_TABLE(pch_dma_id_table) = {
1025 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
1026 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
1027 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
1028 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
1029 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
1030 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */
1031 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */
1032 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */
1033 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */
1034 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */
1035 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */
1036 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */
1037 { 0, },
1038 };
1039
1040 static struct pci_driver pch_dma_driver = {
1041 .name = DRV_NAME,
1042 .id_table = pch_dma_id_table,
1043 .probe = pch_dma_probe,
1044 .remove = __devexit_p(pch_dma_remove),
1045 #ifdef CONFIG_PM
1046 .suspend = pch_dma_suspend,
1047 .resume = pch_dma_resume,
1048 #endif
1049 };
1050
1051 static int __init pch_dma_init(void)
1052 {
1053 return pci_register_driver(&pch_dma_driver);
1054 }
1055
1056 static void __exit pch_dma_exit(void)
1057 {
1058 pci_unregister_driver(&pch_dma_driver);
1059 }
1060
1061 module_init(pch_dma_init);
1062 module_exit(pch_dma_exit);
1063
1064 MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
1065 "DMA controller driver");
1066 MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
1067 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support