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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / dma / pch_dma.c
blob581e7a290d98e1856cb1d0428c53b4aaee6ce518
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Topcliff PCH DMA controller driver
4 * Copyright (c) 2010 Intel Corporation
5 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
6 */
7
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/init.h>
11 #include <linux/pci.h>
12 #include <linux/slab.h>
13 #include <linux/interrupt.h>
14 #include <linux/module.h>
15 #include <linux/pch_dma.h>
16
17 #include "dmaengine.h"
18
19 #define DRV_NAME "pch-dma"
20
21 #define DMA_CTL0_DISABLE 0x0
22 #define DMA_CTL0_SG 0x1
23 #define DMA_CTL0_ONESHOT 0x2
24 #define DMA_CTL0_MODE_MASK_BITS 0x3
25 #define DMA_CTL0_DIR_SHIFT_BITS 2
26 #define DMA_CTL0_BITS_PER_CH 4
27
28 #define DMA_CTL2_START_SHIFT_BITS 8
29 #define DMA_CTL2_IRQ_ENABLE_MASK ((1UL << DMA_CTL2_START_SHIFT_BITS) - 1)
30
31 #define DMA_STATUS_IDLE 0x0
32 #define DMA_STATUS_DESC_READ 0x1
33 #define DMA_STATUS_WAIT 0x2
34 #define DMA_STATUS_ACCESS 0x3
35 #define DMA_STATUS_BITS_PER_CH 2
36 #define DMA_STATUS_MASK_BITS 0x3
37 #define DMA_STATUS_SHIFT_BITS 16
38 #define DMA_STATUS_IRQ(x) (0x1 << (x))
39 #define DMA_STATUS0_ERR(x) (0x1 << ((x) + 8))
40 #define DMA_STATUS2_ERR(x) (0x1 << (x))
41
42 #define DMA_DESC_WIDTH_SHIFT_BITS 12
43 #define DMA_DESC_WIDTH_1_BYTE (0x3 << DMA_DESC_WIDTH_SHIFT_BITS)
44 #define DMA_DESC_WIDTH_2_BYTES (0x2 << DMA_DESC_WIDTH_SHIFT_BITS)
45 #define DMA_DESC_WIDTH_4_BYTES (0x0 << DMA_DESC_WIDTH_SHIFT_BITS)
46 #define DMA_DESC_MAX_COUNT_1_BYTE 0x3FF
47 #define DMA_DESC_MAX_COUNT_2_BYTES 0x3FF
48 #define DMA_DESC_MAX_COUNT_4_BYTES 0x7FF
49 #define DMA_DESC_END_WITHOUT_IRQ 0x0
50 #define DMA_DESC_END_WITH_IRQ 0x1
51 #define DMA_DESC_FOLLOW_WITHOUT_IRQ 0x2
52 #define DMA_DESC_FOLLOW_WITH_IRQ 0x3
53
54 #define MAX_CHAN_NR 12
55
56 #define DMA_MASK_CTL0_MODE 0x33333333
57 #define DMA_MASK_CTL2_MODE 0x00003333
58
59 static unsigned int init_nr_desc_per_channel = 64;
60 module_param(init_nr_desc_per_channel, uint, 0644);
61 MODULE_PARM_DESC(init_nr_desc_per_channel,
62 "initial descriptors per channel (default: 64)");
63
64 struct pch_dma_desc_regs {
65 u32 dev_addr;
66 u32 mem_addr;
67 u32 size;
68 u32 next;
69 };
70
71 struct pch_dma_regs {
72 u32 dma_ctl0;
73 u32 dma_ctl1;
74 u32 dma_ctl2;
75 u32 dma_ctl3;
76 u32 dma_sts0;
77 u32 dma_sts1;
78 u32 dma_sts2;
79 u32 reserved3;
80 struct pch_dma_desc_regs desc[MAX_CHAN_NR];
81 };
82
83 struct pch_dma_desc {
84 struct pch_dma_desc_regs regs;
85 struct dma_async_tx_descriptor txd;
86 struct list_head desc_node;
87 struct list_head tx_list;
88 };
89
90 struct pch_dma_chan {
91 struct dma_chan chan;
92 void __iomem *membase;
93 enum dma_transfer_direction dir;
94 struct tasklet_struct tasklet;
95 unsigned long err_status;
96
97 spinlock_t lock;
98
99 struct list_head active_list;
100 struct list_head queue;
101 struct list_head free_list;
102 unsigned int descs_allocated;
103 };
104
105 #define PDC_DEV_ADDR 0x00
106 #define PDC_MEM_ADDR 0x04
107 #define PDC_SIZE 0x08
108 #define PDC_NEXT 0x0C
109
110 #define channel_readl(pdc, name) \
111 readl((pdc)->membase + PDC_##name)
112 #define channel_writel(pdc, name, val) \
113 writel((val), (pdc)->membase + PDC_##name)
114
115 struct pch_dma {
116 struct dma_device dma;
117 void __iomem *membase;
118 struct dma_pool *pool;
119 struct pch_dma_regs regs;
120 struct pch_dma_desc_regs ch_regs[MAX_CHAN_NR];
121 struct pch_dma_chan channels[MAX_CHAN_NR];
122 };
123
124 #define PCH_DMA_CTL0 0x00
125 #define PCH_DMA_CTL1 0x04
126 #define PCH_DMA_CTL2 0x08
127 #define PCH_DMA_CTL3 0x0C
128 #define PCH_DMA_STS0 0x10
129 #define PCH_DMA_STS1 0x14
130 #define PCH_DMA_STS2 0x18
131
132 #define dma_readl(pd, name) \
133 readl((pd)->membase + PCH_DMA_##name)
134 #define dma_writel(pd, name, val) \
135 writel((val), (pd)->membase + PCH_DMA_##name)
136
137 static inline
138 struct pch_dma_desc *to_pd_desc(struct dma_async_tx_descriptor *txd)
139 {
140 return container_of(txd, struct pch_dma_desc, txd);
141 }
142
143 static inline struct pch_dma_chan *to_pd_chan(struct dma_chan *chan)
144 {
145 return container_of(chan, struct pch_dma_chan, chan);
146 }
147
148 static inline struct pch_dma *to_pd(struct dma_device *ddev)
149 {
150 return container_of(ddev, struct pch_dma, dma);
151 }
152
153 static inline struct device *chan2dev(struct dma_chan *chan)
154 {
155 return &chan->dev->device;
156 }
157
158 static inline struct device *chan2parent(struct dma_chan *chan)
159 {
160 return chan->dev->device.parent;
161 }
162
163 static inline
164 struct pch_dma_desc *pdc_first_active(struct pch_dma_chan *pd_chan)
165 {
166 return list_first_entry(&pd_chan->active_list,
167 struct pch_dma_desc, desc_node);
168 }
169
170 static inline
171 struct pch_dma_desc *pdc_first_queued(struct pch_dma_chan *pd_chan)
172 {
173 return list_first_entry(&pd_chan->queue,
174 struct pch_dma_desc, desc_node);
175 }
176
177 static void pdc_enable_irq(struct dma_chan *chan, int enable)
178 {
179 struct pch_dma *pd = to_pd(chan->device);
180 u32 val;
181 int pos;
182
183 if (chan->chan_id < 8)
184 pos = chan->chan_id;
185 else
186 pos = chan->chan_id + 8;
187
188 val = dma_readl(pd, CTL2);
189
190 if (enable)
191 val |= 0x1 << pos;
192 else
193 val &= ~(0x1 << pos);
194
195 dma_writel(pd, CTL2, val);
196
197 dev_dbg(chan2dev(chan), "pdc_enable_irq: chan %d -> %x\n",
198 chan->chan_id, val);
199 }
200
201 static void pdc_set_dir(struct dma_chan *chan)
202 {
203 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
204 struct pch_dma *pd = to_pd(chan->device);
205 u32 val;
206 u32 mask_mode;
207 u32 mask_ctl;
208
209 if (chan->chan_id < 8) {
210 val = dma_readl(pd, CTL0);
211
212 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
213 (DMA_CTL0_BITS_PER_CH * chan->chan_id);
214 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
215 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
216 val &= mask_mode;
217 if (pd_chan->dir == DMA_MEM_TO_DEV)
218 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
219 DMA_CTL0_DIR_SHIFT_BITS);
220 else
221 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +
222 DMA_CTL0_DIR_SHIFT_BITS));
223
224 val |= mask_ctl;
225 dma_writel(pd, CTL0, val);
226 } else {
227 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
228 val = dma_readl(pd, CTL3);
229
230 mask_mode = DMA_CTL0_MODE_MASK_BITS <<
231 (DMA_CTL0_BITS_PER_CH * ch);
232 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
233 (DMA_CTL0_BITS_PER_CH * ch));
234 val &= mask_mode;
235 if (pd_chan->dir == DMA_MEM_TO_DEV)
236 val |= 0x1 << (DMA_CTL0_BITS_PER_CH * ch +
237 DMA_CTL0_DIR_SHIFT_BITS);
238 else
239 val &= ~(0x1 << (DMA_CTL0_BITS_PER_CH * ch +
240 DMA_CTL0_DIR_SHIFT_BITS));
241 val |= mask_ctl;
242 dma_writel(pd, CTL3, val);
243 }
244
245 dev_dbg(chan2dev(chan), "pdc_set_dir: chan %d -> %x\n",
246 chan->chan_id, val);
247 }
248
249 static void pdc_set_mode(struct dma_chan *chan, u32 mode)
250 {
251 struct pch_dma *pd = to_pd(chan->device);
252 u32 val;
253 u32 mask_ctl;
254 u32 mask_dir;
255
256 if (chan->chan_id < 8) {
257 mask_ctl = DMA_MASK_CTL0_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
258 (DMA_CTL0_BITS_PER_CH * chan->chan_id));
259 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * chan->chan_id +\
260 DMA_CTL0_DIR_SHIFT_BITS);
261 val = dma_readl(pd, CTL0);
262 val &= mask_dir;
263 val |= mode << (DMA_CTL0_BITS_PER_CH * chan->chan_id);
264 val |= mask_ctl;
265 dma_writel(pd, CTL0, val);
266 } else {
267 int ch = chan->chan_id - 8; /* ch8-->0 ch9-->1 ... ch11->3 */
268 mask_ctl = DMA_MASK_CTL2_MODE & ~(DMA_CTL0_MODE_MASK_BITS <<
269 (DMA_CTL0_BITS_PER_CH * ch));
270 mask_dir = 1 << (DMA_CTL0_BITS_PER_CH * ch +\
271 DMA_CTL0_DIR_SHIFT_BITS);
272 val = dma_readl(pd, CTL3);
273 val &= mask_dir;
274 val |= mode << (DMA_CTL0_BITS_PER_CH * ch);
275 val |= mask_ctl;
276 dma_writel(pd, CTL3, val);
277 }
278
279 dev_dbg(chan2dev(chan), "pdc_set_mode: chan %d -> %x\n",
280 chan->chan_id, val);
281 }
282
283 static u32 pdc_get_status0(struct pch_dma_chan *pd_chan)
284 {
285 struct pch_dma *pd = to_pd(pd_chan->chan.device);
286 u32 val;
287
288 val = dma_readl(pd, STS0);
289 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
290 DMA_STATUS_BITS_PER_CH * pd_chan->chan.chan_id));
291 }
292
293 static u32 pdc_get_status2(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, STS2);
299 return DMA_STATUS_MASK_BITS & (val >> (DMA_STATUS_SHIFT_BITS +
300 DMA_STATUS_BITS_PER_CH * (pd_chan->chan.chan_id - 8)));
301 }
302
303 static bool pdc_is_idle(struct pch_dma_chan *pd_chan)
304 {
305 u32 sts;
306
307 if (pd_chan->chan.chan_id < 8)
308 sts = pdc_get_status0(pd_chan);
309 else
310 sts = pdc_get_status2(pd_chan);
311
312
313 if (sts == DMA_STATUS_IDLE)
314 return true;
315 else
316 return false;
317 }
318
319 static void pdc_dostart(struct pch_dma_chan *pd_chan, struct pch_dma_desc* desc)
320 {
321 if (!pdc_is_idle(pd_chan)) {
322 dev_err(chan2dev(&pd_chan->chan),
323 "BUG: Attempt to start non-idle channel\n");
324 return;
325 }
326
327 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> dev_addr: %x\n",
328 pd_chan->chan.chan_id, desc->regs.dev_addr);
329 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> mem_addr: %x\n",
330 pd_chan->chan.chan_id, desc->regs.mem_addr);
331 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> size: %x\n",
332 pd_chan->chan.chan_id, desc->regs.size);
333 dev_dbg(chan2dev(&pd_chan->chan), "chan %d -> next: %x\n",
334 pd_chan->chan.chan_id, desc->regs.next);
335
336 if (list_empty(&desc->tx_list)) {
337 channel_writel(pd_chan, DEV_ADDR, desc->regs.dev_addr);
338 channel_writel(pd_chan, MEM_ADDR, desc->regs.mem_addr);
339 channel_writel(pd_chan, SIZE, desc->regs.size);
340 channel_writel(pd_chan, NEXT, desc->regs.next);
341 pdc_set_mode(&pd_chan->chan, DMA_CTL0_ONESHOT);
342 } else {
343 channel_writel(pd_chan, NEXT, desc->txd.phys);
344 pdc_set_mode(&pd_chan->chan, DMA_CTL0_SG);
345 }
346 }
347
348 static void pdc_chain_complete(struct pch_dma_chan *pd_chan,
349 struct pch_dma_desc *desc)
350 {
351 struct dma_async_tx_descriptor *txd = &desc->txd;
352 struct dmaengine_desc_callback cb;
353
354 dmaengine_desc_get_callback(txd, &cb);
355 list_splice_init(&desc->tx_list, &pd_chan->free_list);
356 list_move(&desc->desc_node, &pd_chan->free_list);
357
358 dmaengine_desc_callback_invoke(&cb, NULL);
359 }
360
361 static void pdc_complete_all(struct pch_dma_chan *pd_chan)
362 {
363 struct pch_dma_desc *desc, *_d;
364 LIST_HEAD(list);
365
366 BUG_ON(!pdc_is_idle(pd_chan));
367
368 if (!list_empty(&pd_chan->queue))
369 pdc_dostart(pd_chan, pdc_first_queued(pd_chan));
370
371 list_splice_init(&pd_chan->active_list, &list);
372 list_splice_init(&pd_chan->queue, &pd_chan->active_list);
373
374 list_for_each_entry_safe(desc, _d, &list, desc_node)
375 pdc_chain_complete(pd_chan, desc);
376 }
377
378 static void pdc_handle_error(struct pch_dma_chan *pd_chan)
379 {
380 struct pch_dma_desc *bad_desc;
381
382 bad_desc = pdc_first_active(pd_chan);
383 list_del(&bad_desc->desc_node);
384
385 list_splice_init(&pd_chan->queue, pd_chan->active_list.prev);
386
387 if (!list_empty(&pd_chan->active_list))
388 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
389
390 dev_crit(chan2dev(&pd_chan->chan), "Bad descriptor submitted\n");
391 dev_crit(chan2dev(&pd_chan->chan), "descriptor cookie: %d\n",
392 bad_desc->txd.cookie);
393
394 pdc_chain_complete(pd_chan, bad_desc);
395 }
396
397 static void pdc_advance_work(struct pch_dma_chan *pd_chan)
398 {
399 if (list_empty(&pd_chan->active_list) ||
400 list_is_singular(&pd_chan->active_list)) {
401 pdc_complete_all(pd_chan);
402 } else {
403 pdc_chain_complete(pd_chan, pdc_first_active(pd_chan));
404 pdc_dostart(pd_chan, pdc_first_active(pd_chan));
405 }
406 }
407
408 static dma_cookie_t pd_tx_submit(struct dma_async_tx_descriptor *txd)
409 {
410 struct pch_dma_desc *desc = to_pd_desc(txd);
411 struct pch_dma_chan *pd_chan = to_pd_chan(txd->chan);
412
413 spin_lock(&pd_chan->lock);
414
415 if (list_empty(&pd_chan->active_list)) {
416 list_add_tail(&desc->desc_node, &pd_chan->active_list);
417 pdc_dostart(pd_chan, desc);
418 } else {
419 list_add_tail(&desc->desc_node, &pd_chan->queue);
420 }
421
422 spin_unlock(&pd_chan->lock);
423 return 0;
424 }
425
426 static struct pch_dma_desc *pdc_alloc_desc(struct dma_chan *chan, gfp_t flags)
427 {
428 struct pch_dma_desc *desc = NULL;
429 struct pch_dma *pd = to_pd(chan->device);
430 dma_addr_t addr;
431
432 desc = dma_pool_zalloc(pd->pool, flags, &addr);
433 if (desc) {
434 INIT_LIST_HEAD(&desc->tx_list);
435 dma_async_tx_descriptor_init(&desc->txd, chan);
436 desc->txd.tx_submit = pd_tx_submit;
437 desc->txd.flags = DMA_CTRL_ACK;
438 desc->txd.phys = addr;
439 }
440
441 return desc;
442 }
443
444 static struct pch_dma_desc *pdc_desc_get(struct pch_dma_chan *pd_chan)
445 {
446 struct pch_dma_desc *desc, *_d;
447 struct pch_dma_desc *ret = NULL;
448 int i = 0;
449
450 spin_lock(&pd_chan->lock);
451 list_for_each_entry_safe(desc, _d, &pd_chan->free_list, desc_node) {
452 i++;
453 if (async_tx_test_ack(&desc->txd)) {
454 list_del(&desc->desc_node);
455 ret = desc;
456 break;
457 }
458 dev_dbg(chan2dev(&pd_chan->chan), "desc %p not ACKed\n", desc);
459 }
460 spin_unlock(&pd_chan->lock);
461 dev_dbg(chan2dev(&pd_chan->chan), "scanned %d descriptors\n", i);
462
463 if (!ret) {
464 ret = pdc_alloc_desc(&pd_chan->chan, GFP_ATOMIC);
465 if (ret) {
466 spin_lock(&pd_chan->lock);
467 pd_chan->descs_allocated++;
468 spin_unlock(&pd_chan->lock);
469 } else {
470 dev_err(chan2dev(&pd_chan->chan),
471 "failed to alloc desc\n");
472 }
473 }
474
475 return ret;
476 }
477
478 static void pdc_desc_put(struct pch_dma_chan *pd_chan,
479 struct pch_dma_desc *desc)
480 {
481 if (desc) {
482 spin_lock(&pd_chan->lock);
483 list_splice_init(&desc->tx_list, &pd_chan->free_list);
484 list_add(&desc->desc_node, &pd_chan->free_list);
485 spin_unlock(&pd_chan->lock);
486 }
487 }
488
489 static int pd_alloc_chan_resources(struct dma_chan *chan)
490 {
491 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
492 struct pch_dma_desc *desc;
493 LIST_HEAD(tmp_list);
494 int i;
495
496 if (!pdc_is_idle(pd_chan)) {
497 dev_dbg(chan2dev(chan), "DMA channel not idle ?\n");
498 return -EIO;
499 }
500
501 if (!list_empty(&pd_chan->free_list))
502 return pd_chan->descs_allocated;
503
504 for (i = 0; i < init_nr_desc_per_channel; i++) {
505 desc = pdc_alloc_desc(chan, GFP_KERNEL);
506
507 if (!desc) {
508 dev_warn(chan2dev(chan),
509 "Only allocated %d initial descriptors\n", i);
510 break;
511 }
512
513 list_add_tail(&desc->desc_node, &tmp_list);
514 }
515
516 spin_lock_irq(&pd_chan->lock);
517 list_splice(&tmp_list, &pd_chan->free_list);
518 pd_chan->descs_allocated = i;
519 dma_cookie_init(chan);
520 spin_unlock_irq(&pd_chan->lock);
521
522 pdc_enable_irq(chan, 1);
523
524 return pd_chan->descs_allocated;
525 }
526
527 static void pd_free_chan_resources(struct dma_chan *chan)
528 {
529 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
530 struct pch_dma *pd = to_pd(chan->device);
531 struct pch_dma_desc *desc, *_d;
532 LIST_HEAD(tmp_list);
533
534 BUG_ON(!pdc_is_idle(pd_chan));
535 BUG_ON(!list_empty(&pd_chan->active_list));
536 BUG_ON(!list_empty(&pd_chan->queue));
537
538 spin_lock_irq(&pd_chan->lock);
539 list_splice_init(&pd_chan->free_list, &tmp_list);
540 pd_chan->descs_allocated = 0;
541 spin_unlock_irq(&pd_chan->lock);
542
543 list_for_each_entry_safe(desc, _d, &tmp_list, desc_node)
544 dma_pool_free(pd->pool, desc, desc->txd.phys);
545
546 pdc_enable_irq(chan, 0);
547 }
548
549 static enum dma_status pd_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
550 struct dma_tx_state *txstate)
551 {
552 return dma_cookie_status(chan, cookie, txstate);
553 }
554
555 static void pd_issue_pending(struct dma_chan *chan)
556 {
557 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
558
559 if (pdc_is_idle(pd_chan)) {
560 spin_lock(&pd_chan->lock);
561 pdc_advance_work(pd_chan);
562 spin_unlock(&pd_chan->lock);
563 }
564 }
565
566 static struct dma_async_tx_descriptor *pd_prep_slave_sg(struct dma_chan *chan,
567 struct scatterlist *sgl, unsigned int sg_len,
568 enum dma_transfer_direction direction, unsigned long flags,
569 void *context)
570 {
571 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
572 struct pch_dma_slave *pd_slave = chan->private;
573 struct pch_dma_desc *first = NULL;
574 struct pch_dma_desc *prev = NULL;
575 struct pch_dma_desc *desc = NULL;
576 struct scatterlist *sg;
577 dma_addr_t reg;
578 int i;
579
580 if (unlikely(!sg_len)) {
581 dev_info(chan2dev(chan), "prep_slave_sg: length is zero!\n");
582 return NULL;
583 }
584
585 if (direction == DMA_DEV_TO_MEM)
586 reg = pd_slave->rx_reg;
587 else if (direction == DMA_MEM_TO_DEV)
588 reg = pd_slave->tx_reg;
589 else
590 return NULL;
591
592 pd_chan->dir = direction;
593 pdc_set_dir(chan);
594
595 for_each_sg(sgl, sg, sg_len, i) {
596 desc = pdc_desc_get(pd_chan);
597
598 if (!desc)
599 goto err_desc_get;
600
601 desc->regs.dev_addr = reg;
602 desc->regs.mem_addr = sg_dma_address(sg);
603 desc->regs.size = sg_dma_len(sg);
604 desc->regs.next = DMA_DESC_FOLLOW_WITHOUT_IRQ;
605
606 switch (pd_slave->width) {
607 case PCH_DMA_WIDTH_1_BYTE:
608 if (desc->regs.size > DMA_DESC_MAX_COUNT_1_BYTE)
609 goto err_desc_get;
610 desc->regs.size |= DMA_DESC_WIDTH_1_BYTE;
611 break;
612 case PCH_DMA_WIDTH_2_BYTES:
613 if (desc->regs.size > DMA_DESC_MAX_COUNT_2_BYTES)
614 goto err_desc_get;
615 desc->regs.size |= DMA_DESC_WIDTH_2_BYTES;
616 break;
617 case PCH_DMA_WIDTH_4_BYTES:
618 if (desc->regs.size > DMA_DESC_MAX_COUNT_4_BYTES)
619 goto err_desc_get;
620 desc->regs.size |= DMA_DESC_WIDTH_4_BYTES;
621 break;
622 default:
623 goto err_desc_get;
624 }
625
626 if (!first) {
627 first = desc;
628 } else {
629 prev->regs.next |= desc->txd.phys;
630 list_add_tail(&desc->desc_node, &first->tx_list);
631 }
632
633 prev = desc;
634 }
635
636 if (flags & DMA_PREP_INTERRUPT)
637 desc->regs.next = DMA_DESC_END_WITH_IRQ;
638 else
639 desc->regs.next = DMA_DESC_END_WITHOUT_IRQ;
640
641 first->txd.cookie = -EBUSY;
642 desc->txd.flags = flags;
643
644 return &first->txd;
645
646 err_desc_get:
647 dev_err(chan2dev(chan), "failed to get desc or wrong parameters\n");
648 pdc_desc_put(pd_chan, first);
649 return NULL;
650 }
651
652 static int pd_device_terminate_all(struct dma_chan *chan)
653 {
654 struct pch_dma_chan *pd_chan = to_pd_chan(chan);
655 struct pch_dma_desc *desc, *_d;
656 LIST_HEAD(list);
657
658 spin_lock_irq(&pd_chan->lock);
659
660 pdc_set_mode(&pd_chan->chan, DMA_CTL0_DISABLE);
661
662 list_splice_init(&pd_chan->active_list, &list);
663 list_splice_init(&pd_chan->queue, &list);
664
665 list_for_each_entry_safe(desc, _d, &list, desc_node)
666 pdc_chain_complete(pd_chan, desc);
667
668 spin_unlock_irq(&pd_chan->lock);
669
670 return 0;
671 }
672
673 static void pdc_tasklet(unsigned long data)
674 {
675 struct pch_dma_chan *pd_chan = (struct pch_dma_chan *)data;
676 unsigned long flags;
677
678 if (!pdc_is_idle(pd_chan)) {
679 dev_err(chan2dev(&pd_chan->chan),
680 "BUG: handle non-idle channel in tasklet\n");
681 return;
682 }
683
684 spin_lock_irqsave(&pd_chan->lock, flags);
685 if (test_and_clear_bit(0, &pd_chan->err_status))
686 pdc_handle_error(pd_chan);
687 else
688 pdc_advance_work(pd_chan);
689 spin_unlock_irqrestore(&pd_chan->lock, flags);
690 }
691
692 static irqreturn_t pd_irq(int irq, void *devid)
693 {
694 struct pch_dma *pd = (struct pch_dma *)devid;
695 struct pch_dma_chan *pd_chan;
696 u32 sts0;
697 u32 sts2;
698 int i;
699 int ret0 = IRQ_NONE;
700 int ret2 = IRQ_NONE;
701
702 sts0 = dma_readl(pd, STS0);
703 sts2 = dma_readl(pd, STS2);
704
705 dev_dbg(pd->dma.dev, "pd_irq sts0: %x\n", sts0);
706
707 for (i = 0; i < pd->dma.chancnt; i++) {
708 pd_chan = &pd->channels[i];
709
710 if (i < 8) {
711 if (sts0 & DMA_STATUS_IRQ(i)) {
712 if (sts0 & DMA_STATUS0_ERR(i))
713 set_bit(0, &pd_chan->err_status);
714
715 tasklet_schedule(&pd_chan->tasklet);
716 ret0 = IRQ_HANDLED;
717 }
718 } else {
719 if (sts2 & DMA_STATUS_IRQ(i - 8)) {
720 if (sts2 & DMA_STATUS2_ERR(i))
721 set_bit(0, &pd_chan->err_status);
722
723 tasklet_schedule(&pd_chan->tasklet);
724 ret2 = IRQ_HANDLED;
725 }
726 }
727 }
728
729 /* clear interrupt bits in status register */
730 if (ret0)
731 dma_writel(pd, STS0, sts0);
732 if (ret2)
733 dma_writel(pd, STS2, sts2);
734
735 return ret0 | ret2;
736 }
737
738 #ifdef CONFIG_PM
739 static void pch_dma_save_regs(struct pch_dma *pd)
740 {
741 struct pch_dma_chan *pd_chan;
742 struct dma_chan *chan, *_c;
743 int i = 0;
744
745 pd->regs.dma_ctl0 = dma_readl(pd, CTL0);
746 pd->regs.dma_ctl1 = dma_readl(pd, CTL1);
747 pd->regs.dma_ctl2 = dma_readl(pd, CTL2);
748 pd->regs.dma_ctl3 = dma_readl(pd, CTL3);
749
750 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
751 pd_chan = to_pd_chan(chan);
752
753 pd->ch_regs[i].dev_addr = channel_readl(pd_chan, DEV_ADDR);
754 pd->ch_regs[i].mem_addr = channel_readl(pd_chan, MEM_ADDR);
755 pd->ch_regs[i].size = channel_readl(pd_chan, SIZE);
756 pd->ch_regs[i].next = channel_readl(pd_chan, NEXT);
757
758 i++;
759 }
760 }
761
762 static void pch_dma_restore_regs(struct pch_dma *pd)
763 {
764 struct pch_dma_chan *pd_chan;
765 struct dma_chan *chan, *_c;
766 int i = 0;
767
768 dma_writel(pd, CTL0, pd->regs.dma_ctl0);
769 dma_writel(pd, CTL1, pd->regs.dma_ctl1);
770 dma_writel(pd, CTL2, pd->regs.dma_ctl2);
771 dma_writel(pd, CTL3, pd->regs.dma_ctl3);
772
773 list_for_each_entry_safe(chan, _c, &pd->dma.channels, device_node) {
774 pd_chan = to_pd_chan(chan);
775
776 channel_writel(pd_chan, DEV_ADDR, pd->ch_regs[i].dev_addr);
777 channel_writel(pd_chan, MEM_ADDR, pd->ch_regs[i].mem_addr);
778 channel_writel(pd_chan, SIZE, pd->ch_regs[i].size);
779 channel_writel(pd_chan, NEXT, pd->ch_regs[i].next);
780
781 i++;
782 }
783 }
784
785 static int pch_dma_suspend(struct pci_dev *pdev, pm_message_t state)
786 {
787 struct pch_dma *pd = pci_get_drvdata(pdev);
788
789 if (pd)
790 pch_dma_save_regs(pd);
791
792 pci_save_state(pdev);
793 pci_disable_device(pdev);
794 pci_set_power_state(pdev, pci_choose_state(pdev, state));
795
796 return 0;
797 }
798
799 static int pch_dma_resume(struct pci_dev *pdev)
800 {
801 struct pch_dma *pd = pci_get_drvdata(pdev);
802 int err;
803
804 pci_set_power_state(pdev, PCI_D0);
805 pci_restore_state(pdev);
806
807 err = pci_enable_device(pdev);
808 if (err) {
809 dev_dbg(&pdev->dev, "failed to enable device\n");
810 return err;
811 }
812
813 if (pd)
814 pch_dma_restore_regs(pd);
815
816 return 0;
817 }
818 #endif
819
820 static int pch_dma_probe(struct pci_dev *pdev,
821 const struct pci_device_id *id)
822 {
823 struct pch_dma *pd;
824 struct pch_dma_regs *regs;
825 unsigned int nr_channels;
826 int err;
827 int i;
828
829 nr_channels = id->driver_data;
830 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
831 if (!pd)
832 return -ENOMEM;
833
834 pci_set_drvdata(pdev, pd);
835
836 err = pci_enable_device(pdev);
837 if (err) {
838 dev_err(&pdev->dev, "Cannot enable PCI device\n");
839 goto err_free_mem;
840 }
841
842 if (!(pci_resource_flags(pdev, 1) & IORESOURCE_MEM)) {
843 dev_err(&pdev->dev, "Cannot find proper base address\n");
844 err = -ENODEV;
845 goto err_disable_pdev;
846 }
847
848 err = pci_request_regions(pdev, DRV_NAME);
849 if (err) {
850 dev_err(&pdev->dev, "Cannot obtain PCI resources\n");
851 goto err_disable_pdev;
852 }
853
854 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
855 if (err) {
856 dev_err(&pdev->dev, "Cannot set proper DMA config\n");
857 goto err_free_res;
858 }
859
860 regs = pd->membase = pci_iomap(pdev, 1, 0);
861 if (!pd->membase) {
862 dev_err(&pdev->dev, "Cannot map MMIO registers\n");
863 err = -ENOMEM;
864 goto err_free_res;
865 }
866
867 pci_set_master(pdev);
868
869 err = request_irq(pdev->irq, pd_irq, IRQF_SHARED, DRV_NAME, pd);
870 if (err) {
871 dev_err(&pdev->dev, "Failed to request IRQ\n");
872 goto err_iounmap;
873 }
874
875 pd->pool = dma_pool_create("pch_dma_desc_pool", &pdev->dev,
876 sizeof(struct pch_dma_desc), 4, 0);
877 if (!pd->pool) {
878 dev_err(&pdev->dev, "Failed to alloc DMA descriptors\n");
879 err = -ENOMEM;
880 goto err_free_irq;
881 }
882
883 pd->dma.dev = &pdev->dev;
884
885 INIT_LIST_HEAD(&pd->dma.channels);
886
887 for (i = 0; i < nr_channels; i++) {
888 struct pch_dma_chan *pd_chan = &pd->channels[i];
889
890 pd_chan->chan.device = &pd->dma;
891 dma_cookie_init(&pd_chan->chan);
892
893 pd_chan->membase = &regs->desc[i];
894
895 spin_lock_init(&pd_chan->lock);
896
897 INIT_LIST_HEAD(&pd_chan->active_list);
898 INIT_LIST_HEAD(&pd_chan->queue);
899 INIT_LIST_HEAD(&pd_chan->free_list);
900
901 tasklet_init(&pd_chan->tasklet, pdc_tasklet,
902 (unsigned long)pd_chan);
903 list_add_tail(&pd_chan->chan.device_node, &pd->dma.channels);
904 }
905
906 dma_cap_zero(pd->dma.cap_mask);
907 dma_cap_set(DMA_PRIVATE, pd->dma.cap_mask);
908 dma_cap_set(DMA_SLAVE, pd->dma.cap_mask);
909
910 pd->dma.device_alloc_chan_resources = pd_alloc_chan_resources;
911 pd->dma.device_free_chan_resources = pd_free_chan_resources;
912 pd->dma.device_tx_status = pd_tx_status;
913 pd->dma.device_issue_pending = pd_issue_pending;
914 pd->dma.device_prep_slave_sg = pd_prep_slave_sg;
915 pd->dma.device_terminate_all = pd_device_terminate_all;
916
917 err = dma_async_device_register(&pd->dma);
918 if (err) {
919 dev_err(&pdev->dev, "Failed to register DMA device\n");
920 goto err_free_pool;
921 }
922
923 return 0;
924
925 err_free_pool:
926 dma_pool_destroy(pd->pool);
927 err_free_irq:
928 free_irq(pdev->irq, pd);
929 err_iounmap:
930 pci_iounmap(pdev, pd->membase);
931 err_free_res:
932 pci_release_regions(pdev);
933 err_disable_pdev:
934 pci_disable_device(pdev);
935 err_free_mem:
936 kfree(pd);
937 return err;
938 }
939
940 static void pch_dma_remove(struct pci_dev *pdev)
941 {
942 struct pch_dma *pd = pci_get_drvdata(pdev);
943 struct pch_dma_chan *pd_chan;
944 struct dma_chan *chan, *_c;
945
946 if (pd) {
947 dma_async_device_unregister(&pd->dma);
948
949 free_irq(pdev->irq, pd);
950
951 list_for_each_entry_safe(chan, _c, &pd->dma.channels,
952 device_node) {
953 pd_chan = to_pd_chan(chan);
954
955 tasklet_kill(&pd_chan->tasklet);
956 }
957
958 dma_pool_destroy(pd->pool);
959 pci_iounmap(pdev, pd->membase);
960 pci_release_regions(pdev);
961 pci_disable_device(pdev);
962 kfree(pd);
963 }
964 }
965
966 /* PCI Device ID of DMA device */
967 #define PCI_DEVICE_ID_EG20T_PCH_DMA_8CH 0x8810
968 #define PCI_DEVICE_ID_EG20T_PCH_DMA_4CH 0x8815
969 #define PCI_DEVICE_ID_ML7213_DMA1_8CH 0x8026
970 #define PCI_DEVICE_ID_ML7213_DMA2_8CH 0x802B
971 #define PCI_DEVICE_ID_ML7213_DMA3_4CH 0x8034
972 #define PCI_DEVICE_ID_ML7213_DMA4_12CH 0x8032
973 #define PCI_DEVICE_ID_ML7223_DMA1_4CH 0x800B
974 #define PCI_DEVICE_ID_ML7223_DMA2_4CH 0x800E
975 #define PCI_DEVICE_ID_ML7223_DMA3_4CH 0x8017
976 #define PCI_DEVICE_ID_ML7223_DMA4_4CH 0x803B
977 #define PCI_DEVICE_ID_ML7831_DMA1_8CH 0x8810
978 #define PCI_DEVICE_ID_ML7831_DMA2_4CH 0x8815
979
980 static const struct pci_device_id pch_dma_id_table[] = {
981 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_8CH), 8 },
982 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_EG20T_PCH_DMA_4CH), 4 },
983 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA1_8CH), 8}, /* UART Video */
984 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA2_8CH), 8}, /* PCMIF SPI */
985 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA3_4CH), 4}, /* FPGA */
986 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_DMA4_12CH), 12}, /* I2S */
987 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA1_4CH), 4}, /* UART */
988 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA2_4CH), 4}, /* Video SPI */
989 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA3_4CH), 4}, /* Security */
990 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_DMA4_4CH), 4}, /* FPGA */
991 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA1_8CH), 8}, /* UART */
992 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_DMA2_4CH), 4}, /* SPI */
993 { 0, },
994 };
995
996 static struct pci_driver pch_dma_driver = {
997 .name = DRV_NAME,
998 .id_table = pch_dma_id_table,
999 .probe = pch_dma_probe,
1000 .remove = pch_dma_remove,
1001 #ifdef CONFIG_PM
1002 .suspend = pch_dma_suspend,
1003 .resume = pch_dma_resume,
1004 #endif
1005 };
1006
1007 module_pci_driver(pch_dma_driver);
1008
1009 MODULE_DESCRIPTION("Intel EG20T PCH / LAPIS Semicon ML7213/ML7223/ML7831 IOH "
1010 "DMA controller driver");
1011 MODULE_AUTHOR("Yong Wang <yong.y.wang@intel.com>");
1012 MODULE_LICENSE("GPL v2");
1013 MODULE_DEVICE_TABLE(pci, pch_dma_id_table);
Linux with added FPC-III support