1/*
2 * Intel MIC Platform Software Stack (MPSS)
3 *
4 * Copyright(c) 2014 Intel Corporation.
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, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * The full GNU General Public License is included in this distribution in
16 * the file called "COPYING".
17 *
18 * Intel MIC X100 DMA Driver.
19 *
20 * Adapted from IOAT dma driver.
21 */
22#include <linux/module.h>
23#include <linux/io.h>
24#include <linux/seq_file.h>
25#include <linux/vmalloc.h>
26
27#include "mic_x100_dma.h"
28
29#define MIC_DMA_MAX_XFER_SIZE_CARD (1 * 1024 * 1024 -\
30 MIC_DMA_ALIGN_BYTES)
31#define MIC_DMA_MAX_XFER_SIZE_HOST (1 * 1024 * 1024 >> 1)
32#define MIC_DMA_DESC_TYPE_SHIFT 60
33#define MIC_DMA_MEMCPY_LEN_SHIFT 46
34#define MIC_DMA_STAT_INTR_SHIFT 59
35
36/* high-water mark for pushing dma descriptors */
37static int mic_dma_pending_level = 4;
38
39/* Status descriptor is used to write a 64 bit value to a memory location */
40enum mic_dma_desc_format_type {
41 MIC_DMA_MEMCPY = 1,
42 MIC_DMA_STATUS,
43};
44
45static inline u32 mic_dma_hw_ring_inc(u32 val)
46{
47 return (val + 1) % MIC_DMA_DESC_RX_SIZE;
48}
49
50static inline u32 mic_dma_hw_ring_dec(u32 val)
51{
52 return val ? val - 1 : MIC_DMA_DESC_RX_SIZE - 1;
53}
54
55static inline void mic_dma_hw_ring_inc_head(struct mic_dma_chan *ch)
56{
57 ch->head = mic_dma_hw_ring_inc(ch->head);
58}
59
60/* Prepare a memcpy desc */
61static inline void mic_dma_memcpy_desc(struct mic_dma_desc *desc,
62 dma_addr_t src_phys, dma_addr_t dst_phys, u64 size)
63{
64 u64 qw0, qw1;
65
66 qw0 = src_phys;
67 qw0 |= (size >> MIC_DMA_ALIGN_SHIFT) << MIC_DMA_MEMCPY_LEN_SHIFT;
68 qw1 = MIC_DMA_MEMCPY;
69 qw1 <<= MIC_DMA_DESC_TYPE_SHIFT;
70 qw1 |= dst_phys;
71 desc->qw0 = qw0;
72 desc->qw1 = qw1;
73}
74
75/* Prepare a status desc. with @data to be written at @dst_phys */
76static inline void mic_dma_prep_status_desc(struct mic_dma_desc *desc, u64 data,
77 dma_addr_t dst_phys, bool generate_intr)
78{
79 u64 qw0, qw1;
80
81 qw0 = data;
82 qw1 = (u64) MIC_DMA_STATUS << MIC_DMA_DESC_TYPE_SHIFT | dst_phys;
83 if (generate_intr)
84 qw1 |= (1ULL << MIC_DMA_STAT_INTR_SHIFT);
85 desc->qw0 = qw0;
86 desc->qw1 = qw1;
87}
88
89static void mic_dma_cleanup(struct mic_dma_chan *ch)
90{
91 struct dma_async_tx_descriptor *tx;
92 u32 tail;
93 u32 last_tail;
94
95 spin_lock(&ch->cleanup_lock);
96 tail = mic_dma_read_cmp_cnt(ch);
97 /*
98 * This is the barrier pair for smp_wmb() in fn.
99 * mic_dma_tx_submit_unlock. It's required so that we read the
100 * updated cookie value from tx->cookie.
101 */
102 smp_rmb();
103 for (last_tail = ch->last_tail; tail != last_tail;) {
104 tx = &ch->tx_array[last_tail];
105 if (tx->cookie) {
106 dma_cookie_complete(tx);
107 dmaengine_desc_get_callback_invoke(tx, NULL);
108 tx->callback = NULL;
109 }
110 last_tail = mic_dma_hw_ring_inc(last_tail);
111 }
112 /* finish all completion callbacks before incrementing tail */
113 smp_mb();
114 ch->last_tail = last_tail;
115 spin_unlock(&ch->cleanup_lock);
116}
117
118static u32 mic_dma_ring_count(u32 head, u32 tail)
119{
120 u32 count;
121
122 if (head >= tail)
123 count = (tail - 0) + (MIC_DMA_DESC_RX_SIZE - head);
124 else
125 count = tail - head;
126 return count - 1;
127}
128
129/* Returns the num. of free descriptors on success, -ENOMEM on failure */
130static int mic_dma_avail_desc_ring_space(struct mic_dma_chan *ch, int required)
131{
132 struct device *dev = mic_dma_ch_to_device(ch);
133 u32 count;
134
135 count = mic_dma_ring_count(ch->head, ch->last_tail);
136 if (count < required) {
137 mic_dma_cleanup(ch);
138 count = mic_dma_ring_count(ch->head, ch->last_tail);
139 }
140
141 if (count < required) {
142 dev_dbg(dev, "Not enough desc space");
143 dev_dbg(dev, "%s %d required=%u, avail=%u\n",
144 __func__, __LINE__, required, count);
145 return -ENOMEM;
146 } else {
147 return count;
148 }
149}
150
151/* Program memcpy descriptors into the descriptor ring and update s/w head ptr*/
152static int mic_dma_prog_memcpy_desc(struct mic_dma_chan *ch, dma_addr_t src,
153 dma_addr_t dst, size_t len)
154{
155 size_t current_transfer_len;
156 size_t max_xfer_size = to_mic_dma_dev(ch)->max_xfer_size;
157 /* 3 is added to make sure we have enough space for status desc */
158 int num_desc = len / max_xfer_size + 3;
159 int ret;
160
161 if (len % max_xfer_size)
162 num_desc++;
163
164 ret = mic_dma_avail_desc_ring_space(ch, num_desc);
165 if (ret < 0)
166 return ret;
167 do {
168 current_transfer_len = min(len, max_xfer_size);
169 mic_dma_memcpy_desc(&ch->desc_ring[ch->head],
170 src, dst, current_transfer_len);
171 mic_dma_hw_ring_inc_head(ch);
172 len -= current_transfer_len;
173 dst = dst + current_transfer_len;
174 src = src + current_transfer_len;
175 } while (len > 0);
176 return 0;
177}
178
179/* It's a h/w quirk and h/w needs 2 status descriptors for every status desc */
180static void mic_dma_prog_intr(struct mic_dma_chan *ch)
181{
182 mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
183 ch->status_dest_micpa, false);
184 mic_dma_hw_ring_inc_head(ch);
185 mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
186 ch->status_dest_micpa, true);
187 mic_dma_hw_ring_inc_head(ch);
188}
189
190/* Wrapper function to program memcpy descriptors/status descriptors */
191static int mic_dma_do_dma(struct mic_dma_chan *ch, int flags, dma_addr_t src,
192 dma_addr_t dst, size_t len)
193{
194 if (len && -ENOMEM == mic_dma_prog_memcpy_desc(ch, src, dst, len)) {
195 return -ENOMEM;
196 } else {
197 /* 3 is the maximum number of status descriptors */
198 int ret = mic_dma_avail_desc_ring_space(ch, 3);
199
200 if (ret < 0)
201 return ret;
202 }
203
204 /* Above mic_dma_prog_memcpy_desc() makes sure we have enough space */
205 if (flags & DMA_PREP_FENCE) {
206 mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
207 ch->status_dest_micpa, false);
208 mic_dma_hw_ring_inc_head(ch);
209 }
210
211 if (flags & DMA_PREP_INTERRUPT)
212 mic_dma_prog_intr(ch);
213
214 return 0;
215}
216
217static inline void mic_dma_issue_pending(struct dma_chan *ch)
218{
219 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
220
221 spin_lock(&mic_ch->issue_lock);
222 /*
223 * Write to head triggers h/w to act on the descriptors.
224 * On MIC, writing the same head value twice causes
225 * a h/w error. On second write, h/w assumes we filled
226 * the entire ring & overwrote some of the descriptors.
227 */
228 if (mic_ch->issued == mic_ch->submitted)
229 goto out;
230 mic_ch->issued = mic_ch->submitted;
231 /*
232 * make descriptor updates visible before advancing head,
233 * this is purposefully not smp_wmb() since we are also
234 * publishing the descriptor updates to a dma device
235 */
236 wmb();
237 mic_dma_write_reg(mic_ch, MIC_DMA_REG_DHPR, mic_ch->issued);
238out:
239 spin_unlock(&mic_ch->issue_lock);
240}
241
242static inline void mic_dma_update_pending(struct mic_dma_chan *ch)
243{
244 if (mic_dma_ring_count(ch->issued, ch->submitted)
245 > mic_dma_pending_level)
246 mic_dma_issue_pending(&ch->api_ch);
247}
248
249static dma_cookie_t mic_dma_tx_submit_unlock(struct dma_async_tx_descriptor *tx)
250{
251 struct mic_dma_chan *mic_ch = to_mic_dma_chan(tx->chan);
252 dma_cookie_t cookie;
253
254 dma_cookie_assign(tx);
255 cookie = tx->cookie;
256 /*
257 * We need an smp write barrier here because another CPU might see
258 * an update to submitted and update h/w head even before we
259 * assigned a cookie to this tx.
260 */
261 smp_wmb();
262 mic_ch->submitted = mic_ch->head;
263 spin_unlock(&mic_ch->prep_lock);
264 mic_dma_update_pending(mic_ch);
265 return cookie;
266}
267
268static inline struct dma_async_tx_descriptor *
269allocate_tx(struct mic_dma_chan *ch)
270{
271 u32 idx = mic_dma_hw_ring_dec(ch->head);
272 struct dma_async_tx_descriptor *tx = &ch->tx_array[idx];
273
274 dma_async_tx_descriptor_init(tx, &ch->api_ch);
275 tx->tx_submit = mic_dma_tx_submit_unlock;
276 return tx;
277}
278
279/* Program a status descriptor with dst as address and value to be written */
280static struct dma_async_tx_descriptor *
281mic_dma_prep_status_lock(struct dma_chan *ch, dma_addr_t dst, u64 src_val,
282 unsigned long flags)
283{
284 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
285 int result;
286
287 spin_lock(&mic_ch->prep_lock);
288 result = mic_dma_avail_desc_ring_space(mic_ch, 4);
289 if (result < 0)
290 goto error;
291 mic_dma_prep_status_desc(&mic_ch->desc_ring[mic_ch->head], src_val, dst,
292 false);
293 mic_dma_hw_ring_inc_head(mic_ch);
294 result = mic_dma_do_dma(mic_ch, flags, 0, 0, 0);
295 if (result < 0)
296 goto error;
297
298 return allocate_tx(mic_ch);
299error:
300 dev_err(mic_dma_ch_to_device(mic_ch),
301 "Error enqueueing dma status descriptor, error=%d\n", result);
302 spin_unlock(&mic_ch->prep_lock);
303 return NULL;
304}
305
306/*
307 * Prepare a memcpy descriptor to be added to the ring.
308 * Note that the temporary descriptor adds an extra overhead of copying the
309 * descriptor to ring. So, we copy directly to the descriptor ring
310 */
311static struct dma_async_tx_descriptor *
312mic_dma_prep_memcpy_lock(struct dma_chan *ch, dma_addr_t dma_dest,
313 dma_addr_t dma_src, size_t len, unsigned long flags)
314{
315 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
316 struct device *dev = mic_dma_ch_to_device(mic_ch);
317 int result;
318
319 if (!len && !flags)
320 return NULL;
321
322 spin_lock(&mic_ch->prep_lock);
323 result = mic_dma_do_dma(mic_ch, flags, dma_src, dma_dest, len);
324 if (result >= 0)
325 return allocate_tx(mic_ch);
326 dev_err(dev, "Error enqueueing dma, error=%d\n", result);
327 spin_unlock(&mic_ch->prep_lock);
328 return NULL;
329}
330
331static struct dma_async_tx_descriptor *
332mic_dma_prep_interrupt_lock(struct dma_chan *ch, unsigned long flags)
333{
334 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
335 int ret;
336
337 spin_lock(&mic_ch->prep_lock);
338 ret = mic_dma_do_dma(mic_ch, flags, 0, 0, 0);
339 if (!ret)
340 return allocate_tx(mic_ch);
341 spin_unlock(&mic_ch->prep_lock);
342 return NULL;
343}
344
345/* Return the status of the transaction */
346static enum dma_status
347mic_dma_tx_status(struct dma_chan *ch, dma_cookie_t cookie,
348 struct dma_tx_state *txstate)
349{
350 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
351
352 if (DMA_COMPLETE != dma_cookie_status(ch, cookie, txstate))
353 mic_dma_cleanup(mic_ch);
354
355 return dma_cookie_status(ch, cookie, txstate);
356}
357
358static irqreturn_t mic_dma_thread_fn(int irq, void *data)
359{
360 mic_dma_cleanup((struct mic_dma_chan *)data);
361 return IRQ_HANDLED;
362}
363
364static irqreturn_t mic_dma_intr_handler(int irq, void *data)
365{
366 struct mic_dma_chan *ch = ((struct mic_dma_chan *)data);
367
368 mic_dma_ack_interrupt(ch);
369 return IRQ_WAKE_THREAD;
370}
371
372static int mic_dma_alloc_desc_ring(struct mic_dma_chan *ch)
373{
374 u64 desc_ring_size = MIC_DMA_DESC_RX_SIZE * sizeof(*ch->desc_ring);
375 struct device *dev = &to_mbus_device(ch)->dev;
376
377 desc_ring_size = ALIGN(desc_ring_size, MIC_DMA_ALIGN_BYTES);
378 ch->desc_ring = kzalloc(desc_ring_size, GFP_KERNEL);
379
380 if (!ch->desc_ring)
381 return -ENOMEM;
382
383 ch->desc_ring_micpa = dma_map_single(dev, ch->desc_ring,
384 desc_ring_size, DMA_BIDIRECTIONAL);
385 if (dma_mapping_error(dev, ch->desc_ring_micpa))
386 goto map_error;
387
388 ch->tx_array = vzalloc(array_size(MIC_DMA_DESC_RX_SIZE,
389 sizeof(*ch->tx_array)));
390 if (!ch->tx_array)
391 goto tx_error;
392 return 0;
393tx_error:
394 dma_unmap_single(dev, ch->desc_ring_micpa, desc_ring_size,
395 DMA_BIDIRECTIONAL);
396map_error:
397 kfree(ch->desc_ring);
398 return -ENOMEM;
399}
400
401static void mic_dma_free_desc_ring(struct mic_dma_chan *ch)
402{
403 u64 desc_ring_size = MIC_DMA_DESC_RX_SIZE * sizeof(*ch->desc_ring);
404
405 vfree(ch->tx_array);
406 desc_ring_size = ALIGN(desc_ring_size, MIC_DMA_ALIGN_BYTES);
407 dma_unmap_single(&to_mbus_device(ch)->dev, ch->desc_ring_micpa,
408 desc_ring_size, DMA_BIDIRECTIONAL);
409 kfree(ch->desc_ring);
410 ch->desc_ring = NULL;
411}
412
413static void mic_dma_free_status_dest(struct mic_dma_chan *ch)
414{
415 dma_unmap_single(&to_mbus_device(ch)->dev, ch->status_dest_micpa,
416 L1_CACHE_BYTES, DMA_BIDIRECTIONAL);
417 kfree(ch->status_dest);
418}
419
420static int mic_dma_alloc_status_dest(struct mic_dma_chan *ch)
421{
422 struct device *dev = &to_mbus_device(ch)->dev;
423
424 ch->status_dest = kzalloc(L1_CACHE_BYTES, GFP_KERNEL);
425 if (!ch->status_dest)
426 return -ENOMEM;
427 ch->status_dest_micpa = dma_map_single(dev, ch->status_dest,
428 L1_CACHE_BYTES, DMA_BIDIRECTIONAL);
429 if (dma_mapping_error(dev, ch->status_dest_micpa)) {
430 kfree(ch->status_dest);
431 ch->status_dest = NULL;
432 return -ENOMEM;
433 }
434 return 0;
435}
436
437static int mic_dma_check_chan(struct mic_dma_chan *ch)
438{
439 if (mic_dma_read_reg(ch, MIC_DMA_REG_DCHERR) ||
440 mic_dma_read_reg(ch, MIC_DMA_REG_DSTAT) & MIC_DMA_CHAN_QUIESCE) {
441 mic_dma_disable_chan(ch);
442 mic_dma_chan_mask_intr(ch);
443 dev_err(mic_dma_ch_to_device(ch),
444 "%s %d error setting up mic dma chan %d\n",
445 __func__, __LINE__, ch->ch_num);
446 return -EBUSY;
447 }
448 return 0;
449}
450
451static int mic_dma_chan_setup(struct mic_dma_chan *ch)
452{
453 if (MIC_DMA_CHAN_MIC == ch->owner)
454 mic_dma_chan_set_owner(ch);
455 mic_dma_disable_chan(ch);
456 mic_dma_chan_mask_intr(ch);
457 mic_dma_write_reg(ch, MIC_DMA_REG_DCHERRMSK, 0);
458 mic_dma_chan_set_desc_ring(ch);
459 ch->last_tail = mic_dma_read_reg(ch, MIC_DMA_REG_DTPR);
460 ch->head = ch->last_tail;
461 ch->issued = 0;
462 mic_dma_chan_unmask_intr(ch);
463 mic_dma_enable_chan(ch);
464 return mic_dma_check_chan(ch);
465}
466
467static void mic_dma_chan_destroy(struct mic_dma_chan *ch)
468{
469 mic_dma_disable_chan(ch);
470 mic_dma_chan_mask_intr(ch);
471}
472
473static int mic_dma_setup_irq(struct mic_dma_chan *ch)
474{
475 ch->cookie =
476 to_mbus_hw_ops(ch)->request_threaded_irq(to_mbus_device(ch),
477 mic_dma_intr_handler, mic_dma_thread_fn,
478 "mic dma_channel", ch, ch->ch_num);
479 return PTR_ERR_OR_ZERO(ch->cookie);
480}
481
482static inline void mic_dma_free_irq(struct mic_dma_chan *ch)
483{
484 to_mbus_hw_ops(ch)->free_irq(to_mbus_device(ch), ch->cookie, ch);
485}
486
487static int mic_dma_chan_init(struct mic_dma_chan *ch)
488{
489 int ret = mic_dma_alloc_desc_ring(ch);
490
491 if (ret)
492 goto ring_error;
493 ret = mic_dma_alloc_status_dest(ch);
494 if (ret)
495 goto status_error;
496 ret = mic_dma_chan_setup(ch);
497 if (ret)
498 goto chan_error;
499 return ret;
500chan_error:
501 mic_dma_free_status_dest(ch);
502status_error:
503 mic_dma_free_desc_ring(ch);
504ring_error:
505 return ret;
506}
507
508static int mic_dma_drain_chan(struct mic_dma_chan *ch)
509{
510 struct dma_async_tx_descriptor *tx;
511 int err = 0;
512 dma_cookie_t cookie;
513
514 tx = mic_dma_prep_memcpy_lock(&ch->api_ch, 0, 0, 0, DMA_PREP_FENCE);
515 if (!tx) {
516 err = -ENOMEM;
517 goto error;
518 }
519
520 cookie = tx->tx_submit(tx);
521 if (dma_submit_error(cookie))
522 err = -ENOMEM;
523 else
524 err = dma_sync_wait(&ch->api_ch, cookie);
525 if (err) {
526 dev_err(mic_dma_ch_to_device(ch), "%s %d TO chan 0x%x\n",
527 __func__, __LINE__, ch->ch_num);
528 err = -EIO;
529 }
530error:
531 mic_dma_cleanup(ch);
532 return err;
533}
534
535static inline void mic_dma_chan_uninit(struct mic_dma_chan *ch)
536{
537 mic_dma_chan_destroy(ch);
538 mic_dma_cleanup(ch);
539 mic_dma_free_status_dest(ch);
540 mic_dma_free_desc_ring(ch);
541}
542
543static int mic_dma_init(struct mic_dma_device *mic_dma_dev,
544 enum mic_dma_chan_owner owner)
545{
546 int i, first_chan = mic_dma_dev->start_ch;
547 struct mic_dma_chan *ch;
548 int ret;
549
550 for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
551 ch = &mic_dma_dev->mic_ch[i];
552 ch->ch_num = i;
553 ch->owner = owner;
554 spin_lock_init(&ch->cleanup_lock);
555 spin_lock_init(&ch->prep_lock);
556 spin_lock_init(&ch->issue_lock);
557 ret = mic_dma_setup_irq(ch);
558 if (ret)
559 goto error;
560 }
561 return 0;
562error:
563 for (i = i - 1; i >= first_chan; i--)
564 mic_dma_free_irq(ch);
565 return ret;
566}
567
568static void mic_dma_uninit(struct mic_dma_device *mic_dma_dev)
569{
570 int i, first_chan = mic_dma_dev->start_ch;
571 struct mic_dma_chan *ch;
572
573 for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
574 ch = &mic_dma_dev->mic_ch[i];
575 mic_dma_free_irq(ch);
576 }
577}
578
579static int mic_dma_alloc_chan_resources(struct dma_chan *ch)
580{
581 int ret = mic_dma_chan_init(to_mic_dma_chan(ch));
582 if (ret)
583 return ret;
584 return MIC_DMA_DESC_RX_SIZE;
585}
586
587static void mic_dma_free_chan_resources(struct dma_chan *ch)
588{
589 struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
590 mic_dma_drain_chan(mic_ch);
591 mic_dma_chan_uninit(mic_ch);
592}
593
594/* Set the fn. handlers and register the dma device with dma api */
595static int mic_dma_register_dma_device(struct mic_dma_device *mic_dma_dev,
596 enum mic_dma_chan_owner owner)
597{
598 int i, first_chan = mic_dma_dev->start_ch;
599
600 dma_cap_zero(mic_dma_dev->dma_dev.cap_mask);
601 /*
602 * This dma engine is not capable of host memory to host memory
603 * transfers
604 */
605 dma_cap_set(DMA_MEMCPY, mic_dma_dev->dma_dev.cap_mask);
606
607 if (MIC_DMA_CHAN_HOST == owner)
608 dma_cap_set(DMA_PRIVATE, mic_dma_dev->dma_dev.cap_mask);
609 mic_dma_dev->dma_dev.device_alloc_chan_resources =
610 mic_dma_alloc_chan_resources;
611 mic_dma_dev->dma_dev.device_free_chan_resources =
612 mic_dma_free_chan_resources;
613 mic_dma_dev->dma_dev.device_tx_status = mic_dma_tx_status;
614 mic_dma_dev->dma_dev.device_prep_dma_memcpy = mic_dma_prep_memcpy_lock;
615 mic_dma_dev->dma_dev.device_prep_dma_imm_data =
616 mic_dma_prep_status_lock;
617 mic_dma_dev->dma_dev.device_prep_dma_interrupt =
618 mic_dma_prep_interrupt_lock;
619 mic_dma_dev->dma_dev.device_issue_pending = mic_dma_issue_pending;
620 mic_dma_dev->dma_dev.copy_align = MIC_DMA_ALIGN_SHIFT;
621 INIT_LIST_HEAD(&mic_dma_dev->dma_dev.channels);
622 for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
623 mic_dma_dev->mic_ch[i].api_ch.device = &mic_dma_dev->dma_dev;
624 dma_cookie_init(&mic_dma_dev->mic_ch[i].api_ch);
625 list_add_tail(&mic_dma_dev->mic_ch[i].api_ch.device_node,
626 &mic_dma_dev->dma_dev.channels);
627 }
628 return dmaenginem_async_device_register(&mic_dma_dev->dma_dev);
629}
630
631/*
632 * Initializes dma channels and registers the dma device with the
633 * dma engine api.
634 */
635static struct mic_dma_device *mic_dma_dev_reg(struct mbus_device *mbdev,
636 enum mic_dma_chan_owner owner)
637{
638 struct mic_dma_device *mic_dma_dev;
639 int ret;
640 struct device *dev = &mbdev->dev;
641
642 mic_dma_dev = devm_kzalloc(dev, sizeof(*mic_dma_dev), GFP_KERNEL);
643 if (!mic_dma_dev) {
644 ret = -ENOMEM;
645 goto alloc_error;
646 }
647 mic_dma_dev->mbdev = mbdev;
648 mic_dma_dev->dma_dev.dev = dev;
649 mic_dma_dev->mmio = mbdev->mmio_va;
650 if (MIC_DMA_CHAN_HOST == owner) {
651 mic_dma_dev->start_ch = 0;
652 mic_dma_dev->max_xfer_size = MIC_DMA_MAX_XFER_SIZE_HOST;
653 } else {
654 mic_dma_dev->start_ch = 4;
655 mic_dma_dev->max_xfer_size = MIC_DMA_MAX_XFER_SIZE_CARD;
656 }
657 ret = mic_dma_init(mic_dma_dev, owner);
658 if (ret)
659 goto init_error;
660 ret = mic_dma_register_dma_device(mic_dma_dev, owner);
661 if (ret)
662 goto reg_error;
663 return mic_dma_dev;
664reg_error:
665 mic_dma_uninit(mic_dma_dev);
666init_error:
667 mic_dma_dev = NULL;
668alloc_error:
669 dev_err(dev, "Error at %s %d ret=%d\n", __func__, __LINE__, ret);
670 return mic_dma_dev;
671}
672
673static void mic_dma_dev_unreg(struct mic_dma_device *mic_dma_dev)
674{
675 mic_dma_uninit(mic_dma_dev);
676}
677
678/* DEBUGFS CODE */
679static int mic_dma_reg_show(struct seq_file *s, void *pos)
680{
681 struct mic_dma_device *mic_dma_dev = s->private;
682 int i, chan_num, first_chan = mic_dma_dev->start_ch;
683 struct mic_dma_chan *ch;
684
685 seq_printf(s, "SBOX_DCR: %#x\n",
686 mic_dma_mmio_read(&mic_dma_dev->mic_ch[first_chan],
687 MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR));
688 seq_puts(s, "DMA Channel Registers\n");
689 seq_printf(s, "%-10s| %-10s %-10s %-10s %-10s %-10s",
690 "Channel", "DCAR", "DTPR", "DHPR", "DRAR_HI", "DRAR_LO");
691 seq_printf(s, " %-11s %-14s %-10s\n", "DCHERR", "DCHERRMSK", "DSTAT");
692 for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
693 ch = &mic_dma_dev->mic_ch[i];
694 chan_num = ch->ch_num;
695 seq_printf(s, "%-10i| %-#10x %-#10x %-#10x %-#10x",
696 chan_num,
697 mic_dma_read_reg(ch, MIC_DMA_REG_DCAR),
698 mic_dma_read_reg(ch, MIC_DMA_REG_DTPR),
699 mic_dma_read_reg(ch, MIC_DMA_REG_DHPR),
700 mic_dma_read_reg(ch, MIC_DMA_REG_DRAR_HI));
701 seq_printf(s, " %-#10x %-#10x %-#14x %-#10x\n",
702 mic_dma_read_reg(ch, MIC_DMA_REG_DRAR_LO),
703 mic_dma_read_reg(ch, MIC_DMA_REG_DCHERR),
704 mic_dma_read_reg(ch, MIC_DMA_REG_DCHERRMSK),
705 mic_dma_read_reg(ch, MIC_DMA_REG_DSTAT));
706 }
707 return 0;
708}
709
710DEFINE_SHOW_ATTRIBUTE(mic_dma_reg);
711
712/* Debugfs parent dir */
713static struct dentry *mic_dma_dbg;
714
715static int mic_dma_driver_probe(struct mbus_device *mbdev)
716{
717 struct mic_dma_device *mic_dma_dev;
718 enum mic_dma_chan_owner owner;
719
720 if (MBUS_DEV_DMA_MIC == mbdev->id.device)
721 owner = MIC_DMA_CHAN_MIC;
722 else
723 owner = MIC_DMA_CHAN_HOST;
724
725 mic_dma_dev = mic_dma_dev_reg(mbdev, owner);
726 dev_set_drvdata(&mbdev->dev, mic_dma_dev);
727
728 if (mic_dma_dbg) {
729 mic_dma_dev->dbg_dir = debugfs_create_dir(dev_name(&mbdev->dev),
730 mic_dma_dbg);
731 if (mic_dma_dev->dbg_dir)
732 debugfs_create_file("mic_dma_reg", 0444,
733 mic_dma_dev->dbg_dir, mic_dma_dev,
734 &mic_dma_reg_fops);
735 }
736 return 0;
737}
738
739static void mic_dma_driver_remove(struct mbus_device *mbdev)
740{
741 struct mic_dma_device *mic_dma_dev;
742
743 mic_dma_dev = dev_get_drvdata(&mbdev->dev);
744 debugfs_remove_recursive(mic_dma_dev->dbg_dir);
745 mic_dma_dev_unreg(mic_dma_dev);
746}
747
748static struct mbus_device_id id_table[] = {
749 {MBUS_DEV_DMA_MIC, MBUS_DEV_ANY_ID},
750 {MBUS_DEV_DMA_HOST, MBUS_DEV_ANY_ID},
751 {0},
752};
753
754static struct mbus_driver mic_dma_driver = {
755 .driver.name = KBUILD_MODNAME,
756 .driver.owner = THIS_MODULE,
757 .id_table = id_table,
758 .probe = mic_dma_driver_probe,
759 .remove = mic_dma_driver_remove,
760};
761
762static int __init mic_x100_dma_init(void)
763{
764 int rc = mbus_register_driver(&mic_dma_driver);
765 if (rc)
766 return rc;
767 mic_dma_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
768 return 0;
769}
770
771static void __exit mic_x100_dma_exit(void)
772{
773 debugfs_remove_recursive(mic_dma_dbg);
774 mbus_unregister_driver(&mic_dma_driver);
775}
776
777module_init(mic_x100_dma_init);
778module_exit(mic_x100_dma_exit);
779
780MODULE_DEVICE_TABLE(mbus, id_table);
781MODULE_AUTHOR("Intel Corporation");
782MODULE_DESCRIPTION("Intel(R) MIC X100 DMA Driver");
783MODULE_LICENSE("GPL v2");
784