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Merge remote-tracking branch 'lightnvm/for-next'
[deliverable/linux.git] / drivers / dma / pch_dma.c
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
16 #include <linux/dmaengine.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/init.h>
19 #include <linux/pci.h>
20 #include <linux/slab.h>
21 #include <linux/interrupt.h>
22 #include <linux/module.h>
23 #include <linux/pch_dma.h>
24
25 #include "dmaengine.h"
26
27 #define DRV_NAME "pch-dma"
28
29 #define DMA_CTL0_DISABLE 0x0
30 #define DMA_CTL0_SG 0x1
31 #define DMA_CTL0_ONESHOT 0x2
32 #define DMA_CTL0_MODE_MASK_BITS 0x3
33 #define DMA_CTL0_DIR_SHIFT_BITS 2
34 #define DMA_CTL0_BITS_PER_CH 4
35
36 #define DMA_CTL2_START_SHIFT_BITS 8
37 #define DMA_CTL2_IRQ_ENABLE_MASK ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)
38
39 #define DMA_STATUS_IDLE 0x0
40 #define DMA_STATUS_DESC_READ 0x1
41 #define DMA_STATUS_WAIT 0x2
42 #define DMA_STATUS_ACCESS 0x3
43 #define DMA_STATUS_BITS_PER_CH 2
44 #define DMA_STATUS_MASK_BITS 0x3
45 #define DMA_STATUS_SHIFT_BITS 16
46 #define DMA_STATUS_IRQ(x) (0x1 << (x))
47 #define DMA_STATUS0_ERR(x) (0x1 << ((x) + 8))
48 #define DMA_STATUS2_ERR(x) (0x1 << (x))
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 12
63
64 #define DMA_MASK_CTL0_MODE 0x33333333
65 #define DMA_MASK_CTL2_MODE 0x00003333
66
67 static unsigned int init_nr_desc_per_channel = 64;
68 module_param(init_nr_desc_per_channel, uint, 0644);
69 MODULE_PARM_DESC(init_nr_desc_per_channel,
70 "initial descriptors per channel (default: 64)");
71
72 struct pch_dma_desc_regs {
73 u32 dev_addr;
74 u32 mem_addr;
75 u32 size;
76 u32 next;
77 };
78
79 struct pch_dma_regs {
80 u32 dma_ctl0;
81 u32 dma_ctl1;
82 u32 dma_ctl2;
83 u32 dma_ctl3;
84 u32 dma_sts0;
85 u32 dma_sts1;
86 u32 dma_sts2;
87 u32 reserved3;
88 struct pch_dma_desc_regs desc[MAX_CHAN_NR];
89 };
90
91 struct pch_dma_desc {
92 struct pch_dma_desc_regs regs;
93 struct dma_async_tx_descriptor txd;
94 struct list_head desc_node;
95 struct list_head tx_list;
96 };
97
98 struct pch_dma_chan {
99 struct dma_chan chan;
100 void __iomem *membase;
101 enum dma_transfer_direction dir;
102 struct tasklet_struct tasklet;
103 unsigned long err_status;
104
105 spinlock_t lock;
106
107 struct list_head active_list;
108 struct list_head queue;
109 struct list_head free_list;
110 unsigned int descs_allocated;
111 };
112
113 #define PDC_DEV_ADDR 0x00
114 #define PDC_MEM_ADDR 0x04
115 #define PDC_SIZE 0x08
116 #define PDC_NEXT 0x0C
117
118 #define channel_readl(pdc, name) \
119 readl((pdc)->membase + PDC_##name)
120 #define channel_writel(pdc, name, val) \
121 writel((val), (pdc)->membase + PDC_##name)
122
123 struct pch_dma {
124 struct dma_device dma;
125 void __iomem *membase;
126 struct pci_pool *pool;
127 struct pch_dma_regs regs;
128 struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
129 struct pch_dma_chan channels[MAX_CHAN_NR];
130 };
131
132 #define PCH_DMA_CTL0 0x00
133 #define PCH_DMA_CTL1 0x04
134 #define PCH_DMA_CTL2 0x08
135 #define PCH_DMA_CTL3 0x0C
136 #define PCH_DMA_STS0 0x10
137 #define PCH_DMA_STS1 0x14
138 #define PCH_DMA_STS2 0x18
139
140 #define dma_readl(pd, name) \
141 readl((pd)->membase + PCH_DMA_##name)
142 #define dma_writel(pd, name, val) \
143 writel((val), (pd)->membase + PCH_DMA_##name)
144
145 static inline
146 struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
147 {
148 return container_of(txd, struct pch_dma_desc, txd);
149 }
150
151 static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
152 {
153 return container_of(chan, struct pch_dma_chan, chan);
154 }
155
156 static inline struct pch_dma *to_pd(struct dma_device *ddev)
157 {
158 return container_of(ddev, struct pch_dma, dma);
159 }
160
161 static inline struct device *chan2dev(struct dma_chan *chan)
162 {
163 return &chan->dev->device;
164 }
165
166 static inline struct device *chan2parent(struct dma_chan *chan)
167 {
168 return chan->dev->device.parent;
169 }
170
171 static inline
172 struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
173 {
174 return list_first_entry(&pd_chan->active_list,
175 struct pch_dma_desc, desc_node);
176 }
177
178 static inline
179 struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
180 {
181 return list_first_entry(&pd_chan->queue,
182 struct pch_dma_desc, desc_node);
183 }
184
185 static void pdc_enable_irq(struct dma_chan *chan, int enable)
186 {
187 struct pch_dma *pd = to_pd(chan->device);
188 u32 val;
189 int pos;
190
191 if (chan->chan_id < 8)
192 pos = chan->chan_id;
193 else
194 pos = chan->chan_id + 8;
195
196 val = dma_readl(pd, CTL2);
197
198 if (enable)
199 val |= 0x1 << pos;
200 else
201 val &= ~(0x1 << pos);
202
203 dma_writel(pd, CTL2, val);
204
205 dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
206 chan->chan_id, val);
207 }
208
209 static void pdc_set_dir(struct dma_chan *chan)
210 {
211 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
212 struct pch_dma *pd = to_pd(chan->device);
213 u32 val;
214 u32 mask_mode;
215 u32 mask_ctl;
216
217 if (chan->chan_id < 8) {
218 val = dma_readl(pd, CTL0);
219
220 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
221 (DMA_CTL0_BITS_PER_CH * chan->chan_id);
222 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
223 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
224 val &= mask_mode;
225 if (pd_chan->dir == DMA_MEM_TO_DEV)
226 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
227 DMA_CTL0_DIR_SHIFT_BITS);
228 else
229 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
230 DMA_CTL0_DIR_SHIFT_BITS));
231
232 val |= mask_ctl;
233 dma_writel(pd, CTL0, val);
234 } else {
235 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
236 val = dma_readl(pd, CTL3);
237
238 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
239 (DMA_CTL0_BITS_PER_CH * ch);
240 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
241 (DMA_CTL0_BITS_PER_CH * ch));
242 val &= mask_mode;
243 if (pd_chan->dir == DMA_MEM_TO_DEV)
244 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +
245 DMA_CTL0_DIR_SHIFT_BITS);
246 else
247 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +
248 DMA_CTL0_DIR_SHIFT_BITS));
249 val |= mask_ctl;
250 dma_writel(pd, CTL3, val);
251 }
252
253 dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
254 chan->chan_id, val);
255 }
256
257 static void pdc_set_mode(struct dma_chan *chan, u32 mode)
258 {
259 struct pch_dma *pd = to_pd(chan->device);
260 u32 val;
261 u32 mask_ctl;
262 u32 mask_dir;
263
264 if (chan->chan_id < 8) {
265 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
266 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
267 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\
268 DMA_CTL0_DIR_SHIFT_BITS);
269 val = dma_readl(pd, CTL0);
270 val &= mask_dir;
271 val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
272 val |= mask_ctl;
273 dma_writel(pd, CTL0, val);
274 } else {
275 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
276 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
277 (DMA_CTL0_BITS_PER_CH * ch));
278 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\
279 DMA_CTL0_DIR_SHIFT_BITS);
280 val = dma_readl(pd, CTL3);
281 val &= mask_dir;
282 val |= mode << (DMA_CTL0_BITS_PER_CH * ch);
283 val |= mask_ctl;
284 dma_writel(pd, CTL3, val);
285 }
286
287 dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
288 chan->chan_id, val);
289 }
290
291 static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)
292 {
293 struct pch_dma *pd = to_pd(pd_chan->chan.device);
294 u32 val;
295
296 val = dma_readl(pd, STS0);
297 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
298 DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
299 }
300
301 static u32 pdc_get_status2(struct pch_dma_chan *pd_chan)
302 {
303 struct pch_dma *pd = to_pd(pd_chan->chan.device);
304 u32 val;
305
306 val = dma_readl(pd, STS2);
307 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
308 DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));
309 }
310
311 static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
312 {
313 u32 sts;
314
315 if (pd_chan->chan.chan_id < 8)
316 sts = pdc_get_status0(pd_chan);
317 else
318 sts = pdc_get_status2(pd_chan);
319
320
321 if (sts == DMA_STATUS_IDLE)
322 return true;
323 else
324 return false;
325 }
326
327 static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
328 {
329 if (!pdc_is_idle(pd_chan)) {
330 dev_err(chan2dev(&pd_chan->chan),
331 "BUG: Attempt to start non-idle channel\n");
332 return;
333 }
334
335 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
336 pd_chan->chan.chan_id, desc->regs.dev_addr);
337 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
338 pd_chan->chan.chan_id, desc->regs.mem_addr);
339 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
340 pd_chan->chan.chan_id, desc->regs.size);
341 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
342 pd_chan->chan.chan_id, desc->regs.next);
343
344 if (list_empty(&desc->tx_list)) {
345 channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
346 channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
347 channel_writel(pd_chan, SIZE, desc->regs.size);
348 channel_writel(pd_chan, NEXT, desc->regs.next);
349 pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
350 } else {
351 channel_writel(pd_chan, NEXT, desc->txd.phys);
352 pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
353 }
354 }
355
356 static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
357 struct pch_dma_desc *desc)
358 {
359 struct dma_async_tx_descriptor *txd = &desc->txd;
360 struct dmaengine_desc_callback cb;
361
362 dmaengine_desc_get_callback(txd, &cb);
363 list_splice_init(&desc->tx_list, &pd_chan->free_list);
364 list_move(&desc->desc_node, &pd_chan->free_list);
365
366 dmaengine_desc_callback_invoke(&cb, NULL);
367 }
368
369 static void pdc_complete_all(struct pch_dma_chan *pd_chan)
370 {
371 struct pch_dma_desc *desc, *_d;
372 LIST_HEAD(list);
373
374 BUG_ON(!pdc_is_idle(pd_chan));
375
376 if (!list_empty(&pd_chan->queue))
377 pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
378
379 list_splice_init(&pd_chan->active_list, &list);
380 list_splice_init(&pd_chan->queue, &pd_chan->active_list);
381
382 list_for_each_entry_safe(desc, _d, &list, desc_node)
383 pdc_chain_complete(pd_chan, desc);
384 }
385
386 static void pdc_handle_error(struct pch_dma_chan *pd_chan)
387 {
388 struct pch_dma_desc *bad_desc;
389
390 bad_desc = pdc_first_active(pd_chan);
391 list_del(&bad_desc->desc_node);
392
393 list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
394
395 if (!list_empty(&pd_chan->active_list))
396 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
397
398 dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
399 dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
400 bad_desc->txd.cookie);
401
402 pdc_chain_complete(pd_chan, bad_desc);
403 }
404
405 static void pdc_advance_work(struct pch_dma_chan *pd_chan)
406 {
407 if (list_empty(&pd_chan->active_list) ||
408 list_is_singular(&pd_chan->active_list)) {
409 pdc_complete_all(pd_chan);
410 } else {
411 pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
412 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
413 }
414 }
415
416 static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
417 {
418 struct pch_dma_desc *desc = to_pd_desc(txd);
419 struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
420 dma_cookie_t cookie;
421
422 spin_lock(&pd_chan->lock);
423 cookie = dma_cookie_assign(txd);
424
425 if (list_empty(&pd_chan->active_list)) {
426 list_add_tail(&desc->desc_node, &pd_chan->active_list);
427 pdc_dostart(pd_chan, desc);
428 } else {
429 list_add_tail(&desc->desc_node, &pd_chan->queue);
430 }
431
432 spin_unlock(&pd_chan->lock);
433 return 0;
434 }
435
436 static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
437 {
438 struct pch_dma_desc *desc = NULL;
439 struct pch_dma *pd = to_pd(chan->device);
440 dma_addr_t addr;
441
442 desc = pci_pool_alloc(pd->pool, flags, &addr);
443 if (desc) {
444 memset(desc, 0, sizeof(struct pch_dma_desc));
445 INIT_LIST_HEAD(&desc->tx_list);
446 dma_async_tx_descriptor_init(&desc->txd, chan);
447 desc->txd.tx_submit = pd_tx_submit;
448 desc->txd.flags = DMA_CTRL_ACK;
449 desc->txd.phys = addr;
450 }
451
452 return desc;
453 }
454
455 static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
456 {
457 struct pch_dma_desc *desc, *_d;
458 struct pch_dma_desc *ret = NULL;
459 int i = 0;
460
461 spin_lock(&pd_chan->lock);
462 list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
463 i++;
464 if (async_tx_test_ack(&desc->txd)) {
465 list_del(&desc->desc_node);
466 ret = desc;
467 break;
468 }
469 dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
470 }
471 spin_unlock(&pd_chan->lock);
472 dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
473
474 if (!ret) {
475 ret = pdc_alloc_desc(&pd_chan->chan, GFP_ATOMIC);
476 if (ret) {
477 spin_lock(&pd_chan->lock);
478 pd_chan->descs_allocated++;
479 spin_unlock(&pd_chan->lock);
480 } else {
481 dev_err(chan2dev(&pd_chan->chan),
482 "failed to alloc desc\n");
483 }
484 }
485
486 return ret;
487 }
488
489 static void pdc_desc_put(struct pch_dma_chan *pd_chan,
490 struct pch_dma_desc *desc)
491 {
492 if (desc) {
493 spin_lock(&pd_chan->lock);
494 list_splice_init(&desc->tx_list, &pd_chan->free_list);
495 list_add(&desc->desc_node, &pd_chan->free_list);
496 spin_unlock(&pd_chan->lock);
497 }
498 }
499
500 static int pd_alloc_chan_resources(struct dma_chan *chan)
501 {
502 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
503 struct pch_dma_desc *desc;
504 LIST_HEAD(tmp_list);
505 int i;
506
507 if (!pdc_is_idle(pd_chan)) {
508 dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
509 return -EIO;
510 }
511
512 if (!list_empty(&pd_chan->free_list))
513 return pd_chan->descs_allocated;
514
515 for (i = 0; i < init_nr_desc_per_channel; i++) {
516 desc = pdc_alloc_desc(chan, GFP_KERNEL);
517
518 if (!desc) {
519 dev_warn(chan2dev(chan),
520 "Only allocated %d initial descriptors\n", i);
521 break;
522 }
523
524 list_add_tail(&desc->desc_node, &tmp_list);
525 }
526
527 spin_lock_irq(&pd_chan->lock);
528 list_splice(&tmp_list, &pd_chan->free_list);
529 pd_chan->descs_allocated = i;
530 dma_cookie_init(chan);
531 spin_unlock_irq(&pd_chan->lock);
532
533 pdc_enable_irq(chan, 1);
534
535 return pd_chan->descs_allocated;
536 }
537
538 static void pd_free_chan_resources(struct dma_chan *chan)
539 {
540 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
541 struct pch_dma *pd = to_pd(chan->device);
542 struct pch_dma_desc *desc, *_d;
543 LIST_HEAD(tmp_list);
544
545 BUG_ON(!pdc_is_idle(pd_chan));
546 BUG_ON(!list_empty(&pd_chan->active_list));
547 BUG_ON(!list_empty(&pd_chan->queue));
548
549 spin_lock_irq(&pd_chan->lock);
550 list_splice_init(&pd_chan->free_list, &tmp_list);
551 pd_chan->descs_allocated = 0;
552 spin_unlock_irq(&pd_chan->lock);
553
554 list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
555 pci_pool_free(pd->pool, desc, desc->txd.phys);
556
557 pdc_enable_irq(chan, 0);
558 }
559
560 static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
561 struct dma_tx_state *txstate)
562 {
563 return dma_cookie_status(chan, cookie, txstate);
564 }
565
566 static void pd_issue_pending(struct dma_chan *chan)
567 {
568 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
569
570 if (pdc_is_idle(pd_chan)) {
571 spin_lock(&pd_chan->lock);
572 pdc_advance_work(pd_chan);
573 spin_unlock(&pd_chan->lock);
574 }
575 }
576
577 static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,
578 struct scatterlist *sgl, unsigned int sg_len,
579 enum dma_transfer_direction direction, unsigned long flags,
580 void *context)
581 {
582 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
583 struct pch_dma_slave *pd_slave = chan->private;
584 struct pch_dma_desc *first = NULL;
585 struct pch_dma_desc *prev = NULL;
586 struct pch_dma_desc *desc = NULL;
587 struct scatterlist *sg;
588 dma_addr_t reg;
589 int i;
590
591 if (unlikely(!sg_len)) {
592 dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
593 return NULL;
594 }
595
596 if (direction == DMA_DEV_TO_MEM)
597 reg = pd_slave->rx_reg;
598 else if (direction == DMA_MEM_TO_DEV)
599 reg = pd_slave->tx_reg;
600 else
601 return NULL;
602
603 pd_chan->dir = direction;
604 pdc_set_dir(chan);
605
606 for_each_sg(sgl, sg, sg_len, i) {
607 desc = pdc_desc_get(pd_chan);
608
609 if (!desc)
610 goto err_desc_get;
611
612 desc->regs.dev_addr = reg;
613 desc->regs.mem_addr = sg_dma_address(sg);
614 desc->regs.size = sg_dma_len(sg);
615 desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
616
617 switch (pd_slave->width) {
618 case PCH_DMA_WIDTH_1_BYTE:
619 if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
620 goto err_desc_get;
621 desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
622 break;
623 case PCH_DMA_WIDTH_2_BYTES:
624 if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
625 goto err_desc_get;
626 desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
627 break;
628 case PCH_DMA_WIDTH_4_BYTES:
629 if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
630 goto err_desc_get;
631 desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
632 break;
633 default:
634 goto err_desc_get;
635 }
636
637 if (!first) {
638 first = desc;
639 } else {
640 prev->regs.next |= desc->txd.phys;
641 list_add_tail(&desc->desc_node, &first->tx_list);
642 }
643
644 prev = desc;
645 }
646
647 if (flags & DMA_PREP_INTERRUPT)
648 desc->regs.next = DMA_DESC_END_WITH_IRQ;
649 else
650 desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
651
652 first->txd.cookie = -EBUSY;
653 desc->txd.flags = flags;
654
655 return &first->txd;
656
657 err_desc_get:
658 dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
659 pdc_desc_put(pd_chan, first);
660 return NULL;
661 }
662
663 static int pd_device_terminate_all(struct dma_chan *chan)
664 {
665 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
666 struct pch_dma_desc *desc, *_d;
667 LIST_HEAD(list);
668
669 spin_lock_irq(&pd_chan->lock);
670
671 pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
672
673 list_splice_init(&pd_chan->active_list, &list);
674 list_splice_init(&pd_chan->queue, &list);
675
676 list_for_each_entry_safe(desc, _d, &list, desc_node)
677 pdc_chain_complete(pd_chan, desc);
678
679 spin_unlock_irq(&pd_chan->lock);
680
681 return 0;
682 }
683
684 static void pdc_tasklet(unsigned long data)
685 {
686 struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
687 unsigned long flags;
688
689 if (!pdc_is_idle(pd_chan)) {
690 dev_err(chan2dev(&pd_chan->chan),
691 "BUG: handle non-idle channel in tasklet\n");
692 return;
693 }
694
695 spin_lock_irqsave(&pd_chan->lock, flags);
696 if (test_and_clear_bit(0, &pd_chan->err_status))
697 pdc_handle_error(pd_chan);
698 else
699 pdc_advance_work(pd_chan);
700 spin_unlock_irqrestore(&pd_chan->lock, flags);
701 }
702
703 static irqreturn_t pd_irq(int irq, void *devid)
704 {
705 struct pch_dma *pd = (struct pch_dma *)devid;
706 struct pch_dma_chan *pd_chan;
707 u32 sts0;
708 u32 sts2;
709 int i;
710 int ret0 = IRQ_NONE;
711 int ret2 = IRQ_NONE;
712
713 sts0 = dma_readl(pd, STS0);
714 sts2 = dma_readl(pd, STS2);
715
716 dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
717
718 for (i = 0; i < pd->dma.chancnt; i++) {
719 pd_chan = &pd->channels[i];
720
721 if (i < 8) {
722 if (sts0 & DMA_STATUS_IRQ(i)) {
723 if (sts0 & DMA_STATUS0_ERR(i))
724 set_bit(0, &pd_chan->err_status);
725
726 tasklet_schedule(&pd_chan->tasklet);
727 ret0 = IRQ_HANDLED;
728 }
729 } else {
730 if (sts2 & DMA_STATUS_IRQ(i - 8)) {
731 if (sts2 & DMA_STATUS2_ERR(i))
732 set_bit(0, &pd_chan->err_status);
733
734 tasklet_schedule(&pd_chan->tasklet);
735 ret2 = IRQ_HANDLED;
736 }
737 }
738 }
739
740 /* clear interrupt bits in status register */
741 if (ret0)
742 dma_writel(pd, STS0, sts0);
743 if (ret2)
744 dma_writel(pd, STS2, sts2);
745
746 return ret0 | ret2;
747 }
748
749 #ifdef CONFIG_PM
750 static void pch_dma_save_regs(struct pch_dma *pd)
751 {
752 struct pch_dma_chan *pd_chan;
753 struct dma_chan *chan, *_c;
754 int i = 0;
755
756 pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
757 pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
758 pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
759 pd->regs.dma_ctl3 = dma_readl(pd, CTL3);
760
761 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
762 pd_chan = to_pd_chan(chan);
763
764 pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
765 pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
766 pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
767 pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
768
769 i++;
770 }
771 }
772
773 static void pch_dma_restore_regs(struct pch_dma *pd)
774 {
775 struct pch_dma_chan *pd_chan;
776 struct dma_chan *chan, *_c;
777 int i = 0;
778
779 dma_writel(pd, CTL0, pd->regs.dma_ctl0);
780 dma_writel(pd, CTL1, pd->regs.dma_ctl1);
781 dma_writel(pd, CTL2, pd->regs.dma_ctl2);
782 dma_writel(pd, CTL3, pd->regs.dma_ctl3);
783
784 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
785 pd_chan = to_pd_chan(chan);
786
787 channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
788 channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
789 channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
790 channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
791
792 i++;
793 }
794 }
795
796 static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
797 {
798 struct pch_dma *pd = pci_get_drvdata(pdev);
799
800 if (pd)
801 pch_dma_save_regs(pd);
802
803 pci_save_state(pdev);
804 pci_disable_device(pdev);
805 pci_set_power_state(pdev, pci_choose_state(pdev, state));
806
807 return 0;
808 }
809
810 static int pch_dma_resume(struct pci_dev *pdev)
811 {
812 struct pch_dma *pd = pci_get_drvdata(pdev);
813 int err;
814
815 pci_set_power_state(pdev, PCI_D0);
816 pci_restore_state(pdev);
817
818 err = pci_enable_device(pdev);
819 if (err) {
820 dev_dbg(&pdev->dev, "failed to enable device\n");
821 return err;
822 }
823
824 if (pd)
825 pch_dma_restore_regs(pd);
826
827 return 0;
828 }
829 #endif
830
831 static int pch_dma_probe(struct pci_dev *pdev,
832 const struct pci_device_id *id)
833 {
834 struct pch_dma *pd;
835 struct pch_dma_regs *regs;
836 unsigned int nr_channels;
837 int err;
838 int i;
839
840 nr_channels = id->driver_data;
841 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
842 if (!pd)
843 return -ENOMEM;
844
845 pci_set_drvdata(pdev, pd);
846
847 err = pci_enable_device(pdev);
848 if (err) {
849 dev_err(&pdev->dev, "Cannot enable PCI device\n");
850 goto err_free_mem;
851 }
852
853 if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
854 dev_err(&pdev->dev, "Cannot find proper base address\n");
855 err = -ENODEV;
856 goto err_disable_pdev;
857 }
858
859 err = pci_request_regions(pdev, DRV_NAME);
860 if (err) {
861 dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
862 goto err_disable_pdev;
863 }
864
865 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
866 if (err) {
867 dev_err(&pdev->dev, "Cannot set proper DMA config\n");
868 goto err_free_res;
869 }
870
871 regs = pd->membase = pci_iomap(pdev, 1, 0);
872 if (!pd->membase) {
873 dev_err(&pdev->dev, "Cannot map MMIO registers\n");
874 err = -ENOMEM;
875 goto err_free_res;
876 }
877
878 pci_set_master(pdev);
879
880 err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
881 if (err) {
882 dev_err(&pdev->dev, "Failed to request IRQ\n");
883 goto err_iounmap;
884 }
885
886 pd->pool = pci_pool_create("pch_dma_desc_pool", pdev,
887 sizeof(struct pch_dma_desc), 4, 0);
888 if (!pd->pool) {
889 dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
890 err = -ENOMEM;
891 goto err_free_irq;
892 }
893
894 pd->dma.dev = &pdev->dev;
895
896 INIT_LIST_HEAD(&pd->dma.channels);
897
898 for (i = 0; i < nr_channels; i++) {
899 struct pch_dma_chan *pd_chan = &pd->channels[i];
900
901 pd_chan->chan.device = &pd->dma;
902 dma_cookie_init(&pd_chan->chan);
903
904 pd_chan->membase = &regs->desc[i];
905
906 spin_lock_init(&pd_chan->lock);
907
908 INIT_LIST_HEAD(&pd_chan->active_list);
909 INIT_LIST_HEAD(&pd_chan->queue);
910 INIT_LIST_HEAD(&pd_chan->free_list);
911
912 tasklet_init(&pd_chan->tasklet, pdc_tasklet,
913 (unsigned long)pd_chan);
914 list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
915 }
916
917 dma_cap_zero(pd->dma.cap_mask);
918 dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
919 dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
920
921 pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
922 pd->dma.device_free_chan_resources = pd_free_chan_resources;
923 pd->dma.device_tx_status = pd_tx_status;
924 pd->dma.device_issue_pending = pd_issue_pending;
925 pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
926 pd->dma.device_terminate_all = pd_device_terminate_all;
927
928 err = dma_async_device_register(&pd->dma);
929 if (err) {
930 dev_err(&pdev->dev, "Failed to register DMA device\n");
931 goto err_free_pool;
932 }
933
934 return 0;
935
936 err_free_pool:
937 pci_pool_destroy(pd->pool);
938 err_free_irq:
939 free_irq(pdev->irq, pd);
940 err_iounmap:
941 pci_iounmap(pdev, pd->membase);
942 err_free_res:
943 pci_release_regions(pdev);
944 err_disable_pdev:
945 pci_disable_device(pdev);
946 err_free_mem:
947 kfree(pd);
948 return err;
949 }
950
951 static void pch_dma_remove(struct pci_dev *pdev)
952 {
953 struct pch_dma *pd = pci_get_drvdata(pdev);
954 struct pch_dma_chan *pd_chan;
955 struct dma_chan *chan, *_c;
956
957 if (pd) {
958 dma_async_device_unregister(&pd->dma);
959
960 free_irq(pdev->irq, pd);
961
962 list_for_each_entry_safe(chan, _c, &pd->dma.channels,
963 device_node) {
964 pd_chan = to_pd_chan(chan);
965
966 tasklet_kill(&pd_chan->tasklet);
967 }
968
969 pci_pool_destroy(pd->pool);
970 pci_iounmap(pdev, pd->membase);
971 pci_release_regions(pdev);
972 pci_disable_device(pdev);
973 kfree(pd);
974 }
975 }
976
977 /* PCI Device ID of DMA device */
978 #define PCI_VENDOR_ID_ROHM 0x10DB
979 #define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810
980 #define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815
981 #define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026
982 #define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B
983 #define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034
984 #define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032
985 #define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B
986 #define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E
987 #define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017
988 #define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B
989 #define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810
990 #define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815
991
992 static const struct pci_device_id pch_dma_id_table[] = {
993 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
994 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
995 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
996 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
997 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
998 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */
999 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */
1000 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */
1001 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */
1002 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */
1003 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */
1004 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */
1005 { 0, },
1006 };
1007
1008 static struct pci_driver pch_dma_driver = {
1009 .name = DRV_NAME,
1010 .id_table = pch_dma_id_table,
1011 .probe = pch_dma_probe,
1012 .remove = pch_dma_remove,
1013 #ifdef CONFIG_PM
1014 .suspend = pch_dma_suspend,
1015 .resume = pch_dma_resume,
1016 #endif
1017 };
1018
1019 module_pci_driver(pch_dma_driver);
1020
1021 MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
1022 "DMA controller driver");
1023 MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
1024 MODULE_LICENSE("GPL v2");
1025 MODULE_DEVICE_TABLE(pci, pch_dma_id_table);
Linux kernel - Deliverables
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