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of: MSI: Simplify irqdomain lookup
[linux/fpc-iii.git] / drivers / dma / sun6i-dma.c
blob2db12e493c530ccc369582b46d7943cd92eac31d
1 /*
2 * Copyright (C) 2013-2014 Allwinner Tech Co., Ltd
3 * Author: Sugar <shuge@allwinnertech.com>
4 *
5 * Copyright (C) 2014 Maxime Ripard
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/dmaengine.h>
17 #include <linux/dmapool.h>
18 #include <linux/interrupt.h>
19 #include <linux/module.h>
20 #include <linux/of_dma.h>
21 #include <linux/of_device.h>
22 #include <linux/platform_device.h>
23 #include <linux/reset.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26
27 #include "virt-dma.h"
28
29 /*
30 * Common registers
31 */
32 #define DMA_IRQ_EN(x) ((x) * 0x04)
33 #define DMA_IRQ_HALF BIT(0)
34 #define DMA_IRQ_PKG BIT(1)
35 #define DMA_IRQ_QUEUE BIT(2)
36
37 #define DMA_IRQ_CHAN_NR 8
38 #define DMA_IRQ_CHAN_WIDTH 4
39
40
41 #define DMA_IRQ_STAT(x) ((x) * 0x04 + 0x10)
42
43 #define DMA_STAT 0x30
44
45 /*
46 * sun8i specific registers
47 */
48 #define SUN8I_DMA_GATE 0x20
49 #define SUN8I_DMA_GATE_ENABLE 0x4
50
51 /*
52 * Channels specific registers
53 */
54 #define DMA_CHAN_ENABLE 0x00
55 #define DMA_CHAN_ENABLE_START BIT(0)
56 #define DMA_CHAN_ENABLE_STOP 0
57
58 #define DMA_CHAN_PAUSE 0x04
59 #define DMA_CHAN_PAUSE_PAUSE BIT(1)
60 #define DMA_CHAN_PAUSE_RESUME 0
61
62 #define DMA_CHAN_LLI_ADDR 0x08
63
64 #define DMA_CHAN_CUR_CFG 0x0c
65 #define DMA_CHAN_CFG_SRC_DRQ(x) ((x) & 0x1f)
66 #define DMA_CHAN_CFG_SRC_IO_MODE BIT(5)
67 #define DMA_CHAN_CFG_SRC_LINEAR_MODE (0 << 5)
68 #define DMA_CHAN_CFG_SRC_BURST(x) (((x) & 0x3) << 7)
69 #define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9)
70
71 #define DMA_CHAN_CFG_DST_DRQ(x) (DMA_CHAN_CFG_SRC_DRQ(x) << 16)
72 #define DMA_CHAN_CFG_DST_IO_MODE (DMA_CHAN_CFG_SRC_IO_MODE << 16)
73 #define DMA_CHAN_CFG_DST_LINEAR_MODE (DMA_CHAN_CFG_SRC_LINEAR_MODE << 16)
74 #define DMA_CHAN_CFG_DST_BURST(x) (DMA_CHAN_CFG_SRC_BURST(x) << 16)
75 #define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16)
76
77 #define DMA_CHAN_CUR_SRC 0x10
78
79 #define DMA_CHAN_CUR_DST 0x14
80
81 #define DMA_CHAN_CUR_CNT 0x18
82
83 #define DMA_CHAN_CUR_PARA 0x1c
84
85
86 /*
87 * Various hardware related defines
88 */
89 #define LLI_LAST_ITEM 0xfffff800
90 #define NORMAL_WAIT 8
91 #define DRQ_SDRAM 1
92
93 /*
94 * Hardware channels / ports representation
95 *
96 * The hardware is used in several SoCs, with differing numbers
97 * of channels and endpoints. This structure ties those numbers
98 * to a certain compatible string.
99 */
100 struct sun6i_dma_config {
101 u32 nr_max_channels;
102 u32 nr_max_requests;
103 u32 nr_max_vchans;
104 };
105
106 /*
107 * Hardware representation of the LLI
108 *
109 * The hardware will be fed the physical address of this structure,
110 * and read its content in order to start the transfer.
111 */
112 struct sun6i_dma_lli {
113 u32 cfg;
114 u32 src;
115 u32 dst;
116 u32 len;
117 u32 para;
118 u32 p_lli_next;
119
120 /*
121 * This field is not used by the DMA controller, but will be
122 * used by the CPU to go through the list (mostly for dumping
123 * or freeing it).
124 */
125 struct sun6i_dma_lli *v_lli_next;
126 };
127
128
129 struct sun6i_desc {
130 struct virt_dma_desc vd;
131 dma_addr_t p_lli;
132 struct sun6i_dma_lli *v_lli;
133 };
134
135 struct sun6i_pchan {
136 u32 idx;
137 void __iomem *base;
138 struct sun6i_vchan *vchan;
139 struct sun6i_desc *desc;
140 struct sun6i_desc *done;
141 };
142
143 struct sun6i_vchan {
144 struct virt_dma_chan vc;
145 struct list_head node;
146 struct dma_slave_config cfg;
147 struct sun6i_pchan *phy;
148 u8 port;
149 };
150
151 struct sun6i_dma_dev {
152 struct dma_device slave;
153 void __iomem *base;
154 struct clk *clk;
155 int irq;
156 spinlock_t lock;
157 struct reset_control *rstc;
158 struct tasklet_struct task;
159 atomic_t tasklet_shutdown;
160 struct list_head pending;
161 struct dma_pool *pool;
162 struct sun6i_pchan *pchans;
163 struct sun6i_vchan *vchans;
164 const struct sun6i_dma_config *cfg;
165 };
166
167 static struct device *chan2dev(struct dma_chan *chan)
168 {
169 return &chan->dev->device;
170 }
171
172 static inline struct sun6i_dma_dev *to_sun6i_dma_dev(struct dma_device *d)
173 {
174 return container_of(d, struct sun6i_dma_dev, slave);
175 }
176
177 static inline struct sun6i_vchan *to_sun6i_vchan(struct dma_chan *chan)
178 {
179 return container_of(chan, struct sun6i_vchan, vc.chan);
180 }
181
182 static inline struct sun6i_desc *
183 to_sun6i_desc(struct dma_async_tx_descriptor *tx)
184 {
185 return container_of(tx, struct sun6i_desc, vd.tx);
186 }
187
188 static inline void sun6i_dma_dump_com_regs(struct sun6i_dma_dev *sdev)
189 {
190 dev_dbg(sdev->slave.dev, "Common register:\n"
191 "\tmask0(%04x): 0x%08x\n"
192 "\tmask1(%04x): 0x%08x\n"
193 "\tpend0(%04x): 0x%08x\n"
194 "\tpend1(%04x): 0x%08x\n"
195 "\tstats(%04x): 0x%08x\n",
196 DMA_IRQ_EN(0), readl(sdev->base + DMA_IRQ_EN(0)),
197 DMA_IRQ_EN(1), readl(sdev->base + DMA_IRQ_EN(1)),
198 DMA_IRQ_STAT(0), readl(sdev->base + DMA_IRQ_STAT(0)),
199 DMA_IRQ_STAT(1), readl(sdev->base + DMA_IRQ_STAT(1)),
200 DMA_STAT, readl(sdev->base + DMA_STAT));
201 }
202
203 static inline void sun6i_dma_dump_chan_regs(struct sun6i_dma_dev *sdev,
204 struct sun6i_pchan *pchan)
205 {
206 phys_addr_t reg = virt_to_phys(pchan->base);
207
208 dev_dbg(sdev->slave.dev, "Chan %d reg: %pa\n"
209 "\t___en(%04x): \t0x%08x\n"
210 "\tpause(%04x): \t0x%08x\n"
211 "\tstart(%04x): \t0x%08x\n"
212 "\t__cfg(%04x): \t0x%08x\n"
213 "\t__src(%04x): \t0x%08x\n"
214 "\t__dst(%04x): \t0x%08x\n"
215 "\tcount(%04x): \t0x%08x\n"
216 "\t_para(%04x): \t0x%08x\n\n",
217 pchan->idx, &reg,
218 DMA_CHAN_ENABLE,
219 readl(pchan->base + DMA_CHAN_ENABLE),
220 DMA_CHAN_PAUSE,
221 readl(pchan->base + DMA_CHAN_PAUSE),
222 DMA_CHAN_LLI_ADDR,
223 readl(pchan->base + DMA_CHAN_LLI_ADDR),
224 DMA_CHAN_CUR_CFG,
225 readl(pchan->base + DMA_CHAN_CUR_CFG),
226 DMA_CHAN_CUR_SRC,
227 readl(pchan->base + DMA_CHAN_CUR_SRC),
228 DMA_CHAN_CUR_DST,
229 readl(pchan->base + DMA_CHAN_CUR_DST),
230 DMA_CHAN_CUR_CNT,
231 readl(pchan->base + DMA_CHAN_CUR_CNT),
232 DMA_CHAN_CUR_PARA,
233 readl(pchan->base + DMA_CHAN_CUR_PARA));
234 }
235
236 static inline s8 convert_burst(u32 maxburst)
237 {
238 switch (maxburst) {
239 case 1:
240 return 0;
241 case 8:
242 return 2;
243 default:
244 return -EINVAL;
245 }
246 }
247
248 static inline s8 convert_buswidth(enum dma_slave_buswidth addr_width)
249 {
250 if ((addr_width < DMA_SLAVE_BUSWIDTH_1_BYTE) ||
251 (addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES))
252 return -EINVAL;
253
254 return addr_width >> 1;
255 }
256
257 static void *sun6i_dma_lli_add(struct sun6i_dma_lli *prev,
258 struct sun6i_dma_lli *next,
259 dma_addr_t next_phy,
260 struct sun6i_desc *txd)
261 {
262 if ((!prev && !txd) || !next)
263 return NULL;
264
265 if (!prev) {
266 txd->p_lli = next_phy;
267 txd->v_lli = next;
268 } else {
269 prev->p_lli_next = next_phy;
270 prev->v_lli_next = next;
271 }
272
273 next->p_lli_next = LLI_LAST_ITEM;
274 next->v_lli_next = NULL;
275
276 return next;
277 }
278
279 static inline int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli,
280 dma_addr_t src,
281 dma_addr_t dst, u32 len,
282 struct dma_slave_config *config)
283 {
284 u8 src_width, dst_width, src_burst, dst_burst;
285
286 if (!config)
287 return -EINVAL;
288
289 src_burst = convert_burst(config->src_maxburst);
290 if (src_burst)
291 return src_burst;
292
293 dst_burst = convert_burst(config->dst_maxburst);
294 if (dst_burst)
295 return dst_burst;
296
297 src_width = convert_buswidth(config->src_addr_width);
298 if (src_width)
299 return src_width;
300
301 dst_width = convert_buswidth(config->dst_addr_width);
302 if (dst_width)
303 return dst_width;
304
305 lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) |
306 DMA_CHAN_CFG_SRC_WIDTH(src_width) |
307 DMA_CHAN_CFG_DST_BURST(dst_burst) |
308 DMA_CHAN_CFG_DST_WIDTH(dst_width);
309
310 lli->src = src;
311 lli->dst = dst;
312 lli->len = len;
313 lli->para = NORMAL_WAIT;
314
315 return 0;
316 }
317
318 static inline void sun6i_dma_dump_lli(struct sun6i_vchan *vchan,
319 struct sun6i_dma_lli *lli)
320 {
321 phys_addr_t p_lli = virt_to_phys(lli);
322
323 dev_dbg(chan2dev(&vchan->vc.chan),
324 "\n\tdesc: p - %pa v - 0x%p\n"
325 "\t\tc - 0x%08x s - 0x%08x d - 0x%08x\n"
326 "\t\tl - 0x%08x p - 0x%08x n - 0x%08x\n",
327 &p_lli, lli,
328 lli->cfg, lli->src, lli->dst,
329 lli->len, lli->para, lli->p_lli_next);
330 }
331
332 static void sun6i_dma_free_desc(struct virt_dma_desc *vd)
333 {
334 struct sun6i_desc *txd = to_sun6i_desc(&vd->tx);
335 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vd->tx.chan->device);
336 struct sun6i_dma_lli *v_lli, *v_next;
337 dma_addr_t p_lli, p_next;
338
339 if (unlikely(!txd))
340 return;
341
342 p_lli = txd->p_lli;
343 v_lli = txd->v_lli;
344
345 while (v_lli) {
346 v_next = v_lli->v_lli_next;
347 p_next = v_lli->p_lli_next;
348
349 dma_pool_free(sdev->pool, v_lli, p_lli);
350
351 v_lli = v_next;
352 p_lli = p_next;
353 }
354
355 kfree(txd);
356 }
357
358 static int sun6i_dma_start_desc(struct sun6i_vchan *vchan)
359 {
360 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(vchan->vc.chan.device);
361 struct virt_dma_desc *desc = vchan_next_desc(&vchan->vc);
362 struct sun6i_pchan *pchan = vchan->phy;
363 u32 irq_val, irq_reg, irq_offset;
364
365 if (!pchan)
366 return -EAGAIN;
367
368 if (!desc) {
369 pchan->desc = NULL;
370 pchan->done = NULL;
371 return -EAGAIN;
372 }
373
374 list_del(&desc->node);
375
376 pchan->desc = to_sun6i_desc(&desc->tx);
377 pchan->done = NULL;
378
379 sun6i_dma_dump_lli(vchan, pchan->desc->v_lli);
380
381 irq_reg = pchan->idx / DMA_IRQ_CHAN_NR;
382 irq_offset = pchan->idx % DMA_IRQ_CHAN_NR;
383
384 irq_val = readl(sdev->base + DMA_IRQ_EN(irq_offset));
385 irq_val |= DMA_IRQ_QUEUE << (irq_offset * DMA_IRQ_CHAN_WIDTH);
386 writel(irq_val, sdev->base + DMA_IRQ_EN(irq_offset));
387
388 writel(pchan->desc->p_lli, pchan->base + DMA_CHAN_LLI_ADDR);
389 writel(DMA_CHAN_ENABLE_START, pchan->base + DMA_CHAN_ENABLE);
390
391 sun6i_dma_dump_com_regs(sdev);
392 sun6i_dma_dump_chan_regs(sdev, pchan);
393
394 return 0;
395 }
396
397 static void sun6i_dma_tasklet(unsigned long data)
398 {
399 struct sun6i_dma_dev *sdev = (struct sun6i_dma_dev *)data;
400 const struct sun6i_dma_config *cfg = sdev->cfg;
401 struct sun6i_vchan *vchan;
402 struct sun6i_pchan *pchan;
403 unsigned int pchan_alloc = 0;
404 unsigned int pchan_idx;
405
406 list_for_each_entry(vchan, &sdev->slave.channels, vc.chan.device_node) {
407 spin_lock_irq(&vchan->vc.lock);
408
409 pchan = vchan->phy;
410
411 if (pchan && pchan->done) {
412 if (sun6i_dma_start_desc(vchan)) {
413 /*
414 * No current txd associated with this channel
415 */
416 dev_dbg(sdev->slave.dev, "pchan %u: free\n",
417 pchan->idx);
418
419 /* Mark this channel free */
420 vchan->phy = NULL;
421 pchan->vchan = NULL;
422 }
423 }
424 spin_unlock_irq(&vchan->vc.lock);
425 }
426
427 spin_lock_irq(&sdev->lock);
428 for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) {
429 pchan = &sdev->pchans[pchan_idx];
430
431 if (pchan->vchan || list_empty(&sdev->pending))
432 continue;
433
434 vchan = list_first_entry(&sdev->pending,
435 struct sun6i_vchan, node);
436
437 /* Remove from pending channels */
438 list_del_init(&vchan->node);
439 pchan_alloc |= BIT(pchan_idx);
440
441 /* Mark this channel allocated */
442 pchan->vchan = vchan;
443 vchan->phy = pchan;
444 dev_dbg(sdev->slave.dev, "pchan %u: alloc vchan %p\n",
445 pchan->idx, &vchan->vc);
446 }
447 spin_unlock_irq(&sdev->lock);
448
449 for (pchan_idx = 0; pchan_idx < cfg->nr_max_channels; pchan_idx++) {
450 if (!(pchan_alloc & BIT(pchan_idx)))
451 continue;
452
453 pchan = sdev->pchans + pchan_idx;
454 vchan = pchan->vchan;
455 if (vchan) {
456 spin_lock_irq(&vchan->vc.lock);
457 sun6i_dma_start_desc(vchan);
458 spin_unlock_irq(&vchan->vc.lock);
459 }
460 }
461 }
462
463 static irqreturn_t sun6i_dma_interrupt(int irq, void *dev_id)
464 {
465 struct sun6i_dma_dev *sdev = dev_id;
466 struct sun6i_vchan *vchan;
467 struct sun6i_pchan *pchan;
468 int i, j, ret = IRQ_NONE;
469 u32 status;
470
471 for (i = 0; i < sdev->cfg->nr_max_channels / DMA_IRQ_CHAN_NR; i++) {
472 status = readl(sdev->base + DMA_IRQ_STAT(i));
473 if (!status)
474 continue;
475
476 dev_dbg(sdev->slave.dev, "DMA irq status %s: 0x%x\n",
477 i ? "high" : "low", status);
478
479 writel(status, sdev->base + DMA_IRQ_STAT(i));
480
481 for (j = 0; (j < DMA_IRQ_CHAN_NR) && status; j++) {
482 if (status & DMA_IRQ_QUEUE) {
483 pchan = sdev->pchans + j;
484 vchan = pchan->vchan;
485
486 if (vchan) {
487 spin_lock(&vchan->vc.lock);
488 vchan_cookie_complete(&pchan->desc->vd);
489 pchan->done = pchan->desc;
490 spin_unlock(&vchan->vc.lock);
491 }
492 }
493
494 status = status >> DMA_IRQ_CHAN_WIDTH;
495 }
496
497 if (!atomic_read(&sdev->tasklet_shutdown))
498 tasklet_schedule(&sdev->task);
499 ret = IRQ_HANDLED;
500 }
501
502 return ret;
503 }
504
505 static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy(
506 struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
507 size_t len, unsigned long flags)
508 {
509 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
510 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
511 struct sun6i_dma_lli *v_lli;
512 struct sun6i_desc *txd;
513 dma_addr_t p_lli;
514 s8 burst, width;
515
516 dev_dbg(chan2dev(chan),
517 "%s; chan: %d, dest: %pad, src: %pad, len: %zu. flags: 0x%08lx\n",
518 __func__, vchan->vc.chan.chan_id, &dest, &src, len, flags);
519
520 if (!len)
521 return NULL;
522
523 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
524 if (!txd)
525 return NULL;
526
527 v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
528 if (!v_lli) {
529 dev_err(sdev->slave.dev, "Failed to alloc lli memory\n");
530 goto err_txd_free;
531 }
532
533 v_lli->src = src;
534 v_lli->dst = dest;
535 v_lli->len = len;
536 v_lli->para = NORMAL_WAIT;
537
538 burst = convert_burst(8);
539 width = convert_buswidth(DMA_SLAVE_BUSWIDTH_4_BYTES);
540 v_lli->cfg |= DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
541 DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
542 DMA_CHAN_CFG_DST_LINEAR_MODE |
543 DMA_CHAN_CFG_SRC_LINEAR_MODE |
544 DMA_CHAN_CFG_SRC_BURST(burst) |
545 DMA_CHAN_CFG_SRC_WIDTH(width) |
546 DMA_CHAN_CFG_DST_BURST(burst) |
547 DMA_CHAN_CFG_DST_WIDTH(width);
548
549 sun6i_dma_lli_add(NULL, v_lli, p_lli, txd);
550
551 sun6i_dma_dump_lli(vchan, v_lli);
552
553 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
554
555 err_txd_free:
556 kfree(txd);
557 return NULL;
558 }
559
560 static struct dma_async_tx_descriptor *sun6i_dma_prep_slave_sg(
561 struct dma_chan *chan, struct scatterlist *sgl,
562 unsigned int sg_len, enum dma_transfer_direction dir,
563 unsigned long flags, void *context)
564 {
565 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
566 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
567 struct dma_slave_config *sconfig = &vchan->cfg;
568 struct sun6i_dma_lli *v_lli, *prev = NULL;
569 struct sun6i_desc *txd;
570 struct scatterlist *sg;
571 dma_addr_t p_lli;
572 int i, ret;
573
574 if (!sgl)
575 return NULL;
576
577 if (!is_slave_direction(dir)) {
578 dev_err(chan2dev(chan), "Invalid DMA direction\n");
579 return NULL;
580 }
581
582 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
583 if (!txd)
584 return NULL;
585
586 for_each_sg(sgl, sg, sg_len, i) {
587 v_lli = dma_pool_alloc(sdev->pool, GFP_NOWAIT, &p_lli);
588 if (!v_lli)
589 goto err_lli_free;
590
591 if (dir == DMA_MEM_TO_DEV) {
592 ret = sun6i_dma_cfg_lli(v_lli, sg_dma_address(sg),
593 sconfig->dst_addr, sg_dma_len(sg),
594 sconfig);
595 if (ret)
596 goto err_cur_lli_free;
597
598 v_lli->cfg |= DMA_CHAN_CFG_DST_IO_MODE |
599 DMA_CHAN_CFG_SRC_LINEAR_MODE |
600 DMA_CHAN_CFG_SRC_DRQ(DRQ_SDRAM) |
601 DMA_CHAN_CFG_DST_DRQ(vchan->port);
602
603 dev_dbg(chan2dev(chan),
604 "%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
605 __func__, vchan->vc.chan.chan_id,
606 &sconfig->dst_addr, &sg_dma_address(sg),
607 sg_dma_len(sg), flags);
608
609 } else {
610 ret = sun6i_dma_cfg_lli(v_lli, sconfig->src_addr,
611 sg_dma_address(sg), sg_dma_len(sg),
612 sconfig);
613 if (ret)
614 goto err_cur_lli_free;
615
616 v_lli->cfg |= DMA_CHAN_CFG_DST_LINEAR_MODE |
617 DMA_CHAN_CFG_SRC_IO_MODE |
618 DMA_CHAN_CFG_DST_DRQ(DRQ_SDRAM) |
619 DMA_CHAN_CFG_SRC_DRQ(vchan->port);
620
621 dev_dbg(chan2dev(chan),
622 "%s; chan: %d, dest: %pad, src: %pad, len: %u. flags: 0x%08lx\n",
623 __func__, vchan->vc.chan.chan_id,
624 &sg_dma_address(sg), &sconfig->src_addr,
625 sg_dma_len(sg), flags);
626 }
627
628 prev = sun6i_dma_lli_add(prev, v_lli, p_lli, txd);
629 }
630
631 dev_dbg(chan2dev(chan), "First: %pad\n", &txd->p_lli);
632 for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
633 sun6i_dma_dump_lli(vchan, prev);
634
635 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
636
637 err_cur_lli_free:
638 dma_pool_free(sdev->pool, v_lli, p_lli);
639 err_lli_free:
640 for (prev = txd->v_lli; prev; prev = prev->v_lli_next)
641 dma_pool_free(sdev->pool, prev, virt_to_phys(prev));
642 kfree(txd);
643 return NULL;
644 }
645
646 static int sun6i_dma_config(struct dma_chan *chan,
647 struct dma_slave_config *config)
648 {
649 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
650
651 memcpy(&vchan->cfg, config, sizeof(*config));
652
653 return 0;
654 }
655
656 static int sun6i_dma_pause(struct dma_chan *chan)
657 {
658 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
659 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
660 struct sun6i_pchan *pchan = vchan->phy;
661
662 dev_dbg(chan2dev(chan), "vchan %p: pause\n", &vchan->vc);
663
664 if (pchan) {
665 writel(DMA_CHAN_PAUSE_PAUSE,
666 pchan->base + DMA_CHAN_PAUSE);
667 } else {
668 spin_lock(&sdev->lock);
669 list_del_init(&vchan->node);
670 spin_unlock(&sdev->lock);
671 }
672
673 return 0;
674 }
675
676 static int sun6i_dma_resume(struct dma_chan *chan)
677 {
678 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
679 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
680 struct sun6i_pchan *pchan = vchan->phy;
681 unsigned long flags;
682
683 dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
684
685 spin_lock_irqsave(&vchan->vc.lock, flags);
686
687 if (pchan) {
688 writel(DMA_CHAN_PAUSE_RESUME,
689 pchan->base + DMA_CHAN_PAUSE);
690 } else if (!list_empty(&vchan->vc.desc_issued)) {
691 spin_lock(&sdev->lock);
692 list_add_tail(&vchan->node, &sdev->pending);
693 spin_unlock(&sdev->lock);
694 }
695
696 spin_unlock_irqrestore(&vchan->vc.lock, flags);
697
698 return 0;
699 }
700
701 static int sun6i_dma_terminate_all(struct dma_chan *chan)
702 {
703 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
704 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
705 struct sun6i_pchan *pchan = vchan->phy;
706 unsigned long flags;
707 LIST_HEAD(head);
708
709 spin_lock(&sdev->lock);
710 list_del_init(&vchan->node);
711 spin_unlock(&sdev->lock);
712
713 spin_lock_irqsave(&vchan->vc.lock, flags);
714
715 vchan_get_all_descriptors(&vchan->vc, &head);
716
717 if (pchan) {
718 writel(DMA_CHAN_ENABLE_STOP, pchan->base + DMA_CHAN_ENABLE);
719 writel(DMA_CHAN_PAUSE_RESUME, pchan->base + DMA_CHAN_PAUSE);
720
721 vchan->phy = NULL;
722 pchan->vchan = NULL;
723 pchan->desc = NULL;
724 pchan->done = NULL;
725 }
726
727 spin_unlock_irqrestore(&vchan->vc.lock, flags);
728
729 vchan_dma_desc_free_list(&vchan->vc, &head);
730
731 return 0;
732 }
733
734 static enum dma_status sun6i_dma_tx_status(struct dma_chan *chan,
735 dma_cookie_t cookie,
736 struct dma_tx_state *state)
737 {
738 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
739 struct sun6i_pchan *pchan = vchan->phy;
740 struct sun6i_dma_lli *lli;
741 struct virt_dma_desc *vd;
742 struct sun6i_desc *txd;
743 enum dma_status ret;
744 unsigned long flags;
745 size_t bytes = 0;
746
747 ret = dma_cookie_status(chan, cookie, state);
748 if (ret == DMA_COMPLETE)
749 return ret;
750
751 spin_lock_irqsave(&vchan->vc.lock, flags);
752
753 vd = vchan_find_desc(&vchan->vc, cookie);
754 txd = to_sun6i_desc(&vd->tx);
755
756 if (vd) {
757 for (lli = txd->v_lli; lli != NULL; lli = lli->v_lli_next)
758 bytes += lli->len;
759 } else if (!pchan || !pchan->desc) {
760 bytes = 0;
761 } else {
762 bytes = readl(pchan->base + DMA_CHAN_CUR_CNT);
763 }
764
765 spin_unlock_irqrestore(&vchan->vc.lock, flags);
766
767 dma_set_residue(state, bytes);
768
769 return ret;
770 }
771
772 static void sun6i_dma_issue_pending(struct dma_chan *chan)
773 {
774 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
775 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
776 unsigned long flags;
777
778 spin_lock_irqsave(&vchan->vc.lock, flags);
779
780 if (vchan_issue_pending(&vchan->vc)) {
781 spin_lock(&sdev->lock);
782
783 if (!vchan->phy && list_empty(&vchan->node)) {
784 list_add_tail(&vchan->node, &sdev->pending);
785 tasklet_schedule(&sdev->task);
786 dev_dbg(chan2dev(chan), "vchan %p: issued\n",
787 &vchan->vc);
788 }
789
790 spin_unlock(&sdev->lock);
791 } else {
792 dev_dbg(chan2dev(chan), "vchan %p: nothing to issue\n",
793 &vchan->vc);
794 }
795
796 spin_unlock_irqrestore(&vchan->vc.lock, flags);
797 }
798
799 static void sun6i_dma_free_chan_resources(struct dma_chan *chan)
800 {
801 struct sun6i_dma_dev *sdev = to_sun6i_dma_dev(chan->device);
802 struct sun6i_vchan *vchan = to_sun6i_vchan(chan);
803 unsigned long flags;
804
805 spin_lock_irqsave(&sdev->lock, flags);
806 list_del_init(&vchan->node);
807 spin_unlock_irqrestore(&sdev->lock, flags);
808
809 vchan_free_chan_resources(&vchan->vc);
810 }
811
812 static struct dma_chan *sun6i_dma_of_xlate(struct of_phandle_args *dma_spec,
813 struct of_dma *ofdma)
814 {
815 struct sun6i_dma_dev *sdev = ofdma->of_dma_data;
816 struct sun6i_vchan *vchan;
817 struct dma_chan *chan;
818 u8 port = dma_spec->args[0];
819
820 if (port > sdev->cfg->nr_max_requests)
821 return NULL;
822
823 chan = dma_get_any_slave_channel(&sdev->slave);
824 if (!chan)
825 return NULL;
826
827 vchan = to_sun6i_vchan(chan);
828 vchan->port = port;
829
830 return chan;
831 }
832
833 static inline void sun6i_kill_tasklet(struct sun6i_dma_dev *sdev)
834 {
835 /* Disable all interrupts from DMA */
836 writel(0, sdev->base + DMA_IRQ_EN(0));
837 writel(0, sdev->base + DMA_IRQ_EN(1));
838
839 /* Prevent spurious interrupts from scheduling the tasklet */
840 atomic_inc(&sdev->tasklet_shutdown);
841
842 /* Make sure we won't have any further interrupts */
843 devm_free_irq(sdev->slave.dev, sdev->irq, sdev);
844
845 /* Actually prevent the tasklet from being scheduled */
846 tasklet_kill(&sdev->task);
847 }
848
849 static inline void sun6i_dma_free(struct sun6i_dma_dev *sdev)
850 {
851 int i;
852
853 for (i = 0; i < sdev->cfg->nr_max_vchans; i++) {
854 struct sun6i_vchan *vchan = &sdev->vchans[i];
855
856 list_del(&vchan->vc.chan.device_node);
857 tasklet_kill(&vchan->vc.task);
858 }
859 }
860
861 /*
862 * For A31:
863 *
864 * There's 16 physical channels that can work in parallel.
865 *
866 * However we have 30 different endpoints for our requests.
867 *
868 * Since the channels are able to handle only an unidirectional
869 * transfer, we need to allocate more virtual channels so that
870 * everyone can grab one channel.
871 *
872 * Some devices can't work in both direction (mostly because it
873 * wouldn't make sense), so we have a bit fewer virtual channels than
874 * 2 channels per endpoints.
875 */
876
877 static struct sun6i_dma_config sun6i_a31_dma_cfg = {
878 .nr_max_channels = 16,
879 .nr_max_requests = 30,
880 .nr_max_vchans = 53,
881 };
882
883 /*
884 * The A23 only has 8 physical channels, a maximum DRQ port id of 24,
885 * and a total of 37 usable source and destination endpoints.
886 */
887
888 static struct sun6i_dma_config sun8i_a23_dma_cfg = {
889 .nr_max_channels = 8,
890 .nr_max_requests = 24,
891 .nr_max_vchans = 37,
892 };
893
894 /*
895 * The H3 has 12 physical channels, a maximum DRQ port id of 27,
896 * and a total of 34 usable source and destination endpoints.
897 */
898
899 static struct sun6i_dma_config sun8i_h3_dma_cfg = {
900 .nr_max_channels = 12,
901 .nr_max_requests = 27,
902 .nr_max_vchans = 34,
903 };
904
905 static const struct of_device_id sun6i_dma_match[] = {
906 { .compatible = "allwinner,sun6i-a31-dma", .data = &sun6i_a31_dma_cfg },
907 { .compatible = "allwinner,sun8i-a23-dma", .data = &sun8i_a23_dma_cfg },
908 { .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
909 { /* sentinel */ }
910 };
911 MODULE_DEVICE_TABLE(of, sun6i_dma_match);
912
913 static int sun6i_dma_probe(struct platform_device *pdev)
914 {
915 const struct of_device_id *device;
916 struct sun6i_dma_dev *sdc;
917 struct resource *res;
918 int ret, i;
919
920 sdc = devm_kzalloc(&pdev->dev, sizeof(*sdc), GFP_KERNEL);
921 if (!sdc)
922 return -ENOMEM;
923
924 device = of_match_device(sun6i_dma_match, &pdev->dev);
925 if (!device)
926 return -ENODEV;
927 sdc->cfg = device->data;
928
929 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
930 sdc->base = devm_ioremap_resource(&pdev->dev, res);
931 if (IS_ERR(sdc->base))
932 return PTR_ERR(sdc->base);
933
934 sdc->irq = platform_get_irq(pdev, 0);
935 if (sdc->irq < 0) {
936 dev_err(&pdev->dev, "Cannot claim IRQ\n");
937 return sdc->irq;
938 }
939
940 sdc->clk = devm_clk_get(&pdev->dev, NULL);
941 if (IS_ERR(sdc->clk)) {
942 dev_err(&pdev->dev, "No clock specified\n");
943 return PTR_ERR(sdc->clk);
944 }
945
946 sdc->rstc = devm_reset_control_get(&pdev->dev, NULL);
947 if (IS_ERR(sdc->rstc)) {
948 dev_err(&pdev->dev, "No reset controller specified\n");
949 return PTR_ERR(sdc->rstc);
950 }
951
952 sdc->pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
953 sizeof(struct sun6i_dma_lli), 4, 0);
954 if (!sdc->pool) {
955 dev_err(&pdev->dev, "No memory for descriptors dma pool\n");
956 return -ENOMEM;
957 }
958
959 platform_set_drvdata(pdev, sdc);
960 INIT_LIST_HEAD(&sdc->pending);
961 spin_lock_init(&sdc->lock);
962
963 dma_cap_set(DMA_PRIVATE, sdc->slave.cap_mask);
964 dma_cap_set(DMA_MEMCPY, sdc->slave.cap_mask);
965 dma_cap_set(DMA_SLAVE, sdc->slave.cap_mask);
966
967 INIT_LIST_HEAD(&sdc->slave.channels);
968 sdc->slave.device_free_chan_resources = sun6i_dma_free_chan_resources;
969 sdc->slave.device_tx_status = sun6i_dma_tx_status;
970 sdc->slave.device_issue_pending = sun6i_dma_issue_pending;
971 sdc->slave.device_prep_slave_sg = sun6i_dma_prep_slave_sg;
972 sdc->slave.device_prep_dma_memcpy = sun6i_dma_prep_dma_memcpy;
973 sdc->slave.copy_align = DMAENGINE_ALIGN_4_BYTES;
974 sdc->slave.device_config = sun6i_dma_config;
975 sdc->slave.device_pause = sun6i_dma_pause;
976 sdc->slave.device_resume = sun6i_dma_resume;
977 sdc->slave.device_terminate_all = sun6i_dma_terminate_all;
978 sdc->slave.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
979 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
980 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
981 sdc->slave.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
982 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
983 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
984 sdc->slave.directions = BIT(DMA_DEV_TO_MEM) |
985 BIT(DMA_MEM_TO_DEV);
986 sdc->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
987 sdc->slave.dev = &pdev->dev;
988
989 sdc->pchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_channels,
990 sizeof(struct sun6i_pchan), GFP_KERNEL);
991 if (!sdc->pchans)
992 return -ENOMEM;
993
994 sdc->vchans = devm_kcalloc(&pdev->dev, sdc->cfg->nr_max_vchans,
995 sizeof(struct sun6i_vchan), GFP_KERNEL);
996 if (!sdc->vchans)
997 return -ENOMEM;
998
999 tasklet_init(&sdc->task, sun6i_dma_tasklet, (unsigned long)sdc);
1000
1001 for (i = 0; i < sdc->cfg->nr_max_channels; i++) {
1002 struct sun6i_pchan *pchan = &sdc->pchans[i];
1003
1004 pchan->idx = i;
1005 pchan->base = sdc->base + 0x100 + i * 0x40;
1006 }
1007
1008 for (i = 0; i < sdc->cfg->nr_max_vchans; i++) {
1009 struct sun6i_vchan *vchan = &sdc->vchans[i];
1010
1011 INIT_LIST_HEAD(&vchan->node);
1012 vchan->vc.desc_free = sun6i_dma_free_desc;
1013 vchan_init(&vchan->vc, &sdc->slave);
1014 }
1015
1016 ret = reset_control_deassert(sdc->rstc);
1017 if (ret) {
1018 dev_err(&pdev->dev, "Couldn't deassert the device from reset\n");
1019 goto err_chan_free;
1020 }
1021
1022 ret = clk_prepare_enable(sdc->clk);
1023 if (ret) {
1024 dev_err(&pdev->dev, "Couldn't enable the clock\n");
1025 goto err_reset_assert;
1026 }
1027
1028 ret = devm_request_irq(&pdev->dev, sdc->irq, sun6i_dma_interrupt, 0,
1029 dev_name(&pdev->dev), sdc);
1030 if (ret) {
1031 dev_err(&pdev->dev, "Cannot request IRQ\n");
1032 goto err_clk_disable;
1033 }
1034
1035 ret = dma_async_device_register(&sdc->slave);
1036 if (ret) {
1037 dev_warn(&pdev->dev, "Failed to register DMA engine device\n");
1038 goto err_irq_disable;
1039 }
1040
1041 ret = of_dma_controller_register(pdev->dev.of_node, sun6i_dma_of_xlate,
1042 sdc);
1043 if (ret) {
1044 dev_err(&pdev->dev, "of_dma_controller_register failed\n");
1045 goto err_dma_unregister;
1046 }
1047
1048 /*
1049 * sun8i variant requires us to toggle a dma gating register,
1050 * as seen in Allwinner's SDK. This register is not documented
1051 * in the A23 user manual.
1052 */
1053 if (of_device_is_compatible(pdev->dev.of_node,
1054 "allwinner,sun8i-a23-dma"))
1055 writel(SUN8I_DMA_GATE_ENABLE, sdc->base + SUN8I_DMA_GATE);
1056
1057 return 0;
1058
1059 err_dma_unregister:
1060 dma_async_device_unregister(&sdc->slave);
1061 err_irq_disable:
1062 sun6i_kill_tasklet(sdc);
1063 err_clk_disable:
1064 clk_disable_unprepare(sdc->clk);
1065 err_reset_assert:
1066 reset_control_assert(sdc->rstc);
1067 err_chan_free:
1068 sun6i_dma_free(sdc);
1069 return ret;
1070 }
1071
1072 static int sun6i_dma_remove(struct platform_device *pdev)
1073 {
1074 struct sun6i_dma_dev *sdc = platform_get_drvdata(pdev);
1075
1076 of_dma_controller_free(pdev->dev.of_node);
1077 dma_async_device_unregister(&sdc->slave);
1078
1079 sun6i_kill_tasklet(sdc);
1080
1081 clk_disable_unprepare(sdc->clk);
1082 reset_control_assert(sdc->rstc);
1083
1084 sun6i_dma_free(sdc);
1085
1086 return 0;
1087 }
1088
1089 static struct platform_driver sun6i_dma_driver = {
1090 .probe = sun6i_dma_probe,
1091 .remove = sun6i_dma_remove,
1092 .driver = {
1093 .name = "sun6i-dma",
1094 .of_match_table = sun6i_dma_match,
1095 },
1096 };
1097 module_platform_driver(sun6i_dma_driver);
1098
1099 MODULE_DESCRIPTION("Allwinner A31 DMA Controller Driver");
1100 MODULE_AUTHOR("Sugar <shuge@allwinnertech.com>");
1101 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1102 MODULE_LICENSE("GPL");
Linux with added FPC-III support