xref: /openbmc/linux/drivers/dma/tegra210-adma.c (revision 2a81ada3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ADMA driver for Nvidia's Tegra210 ADMA controller.
4  *
5  * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/iopoll.h>
10 #include <linux/module.h>
11 #include <linux/of_device.h>
12 #include <linux/of_dma.h>
13 #include <linux/of_irq.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/slab.h>
16 
17 #include "virt-dma.h"
18 
19 #define ADMA_CH_CMD					0x00
20 #define ADMA_CH_STATUS					0x0c
21 #define ADMA_CH_STATUS_XFER_EN				BIT(0)
22 #define ADMA_CH_STATUS_XFER_PAUSED			BIT(1)
23 
24 #define ADMA_CH_INT_STATUS				0x10
25 #define ADMA_CH_INT_STATUS_XFER_DONE			BIT(0)
26 
27 #define ADMA_CH_INT_CLEAR				0x1c
28 #define ADMA_CH_CTRL					0x24
29 #define ADMA_CH_CTRL_DIR(val)				(((val) & 0xf) << 12)
30 #define ADMA_CH_CTRL_DIR_AHUB2MEM			2
31 #define ADMA_CH_CTRL_DIR_MEM2AHUB			4
32 #define ADMA_CH_CTRL_MODE_CONTINUOUS			(2 << 8)
33 #define ADMA_CH_CTRL_FLOWCTRL_EN			BIT(1)
34 #define ADMA_CH_CTRL_XFER_PAUSE_SHIFT			0
35 
36 #define ADMA_CH_CONFIG					0x28
37 #define ADMA_CH_CONFIG_SRC_BUF(val)			(((val) & 0x7) << 28)
38 #define ADMA_CH_CONFIG_TRG_BUF(val)			(((val) & 0x7) << 24)
39 #define ADMA_CH_CONFIG_BURST_SIZE_SHIFT			20
40 #define ADMA_CH_CONFIG_MAX_BURST_SIZE                   16
41 #define ADMA_CH_CONFIG_WEIGHT_FOR_WRR(val)		((val) & 0xf)
42 #define ADMA_CH_CONFIG_MAX_BUFS				8
43 #define TEGRA186_ADMA_CH_CONFIG_OUTSTANDING_REQS(reqs)	(reqs << 4)
44 
45 #define ADMA_CH_FIFO_CTRL				0x2c
46 #define ADMA_CH_TX_FIFO_SIZE_SHIFT			8
47 #define ADMA_CH_RX_FIFO_SIZE_SHIFT			0
48 
49 #define ADMA_CH_LOWER_SRC_ADDR				0x34
50 #define ADMA_CH_LOWER_TRG_ADDR				0x3c
51 #define ADMA_CH_TC					0x44
52 #define ADMA_CH_TC_COUNT_MASK				0x3ffffffc
53 
54 #define ADMA_CH_XFER_STATUS				0x54
55 #define ADMA_CH_XFER_STATUS_COUNT_MASK			0xffff
56 
57 #define ADMA_GLOBAL_CMD					0x00
58 #define ADMA_GLOBAL_SOFT_RESET				0x04
59 
60 #define TEGRA_ADMA_BURST_COMPLETE_TIME			20
61 
62 #define ADMA_CH_REG_FIELD_VAL(val, mask, shift)	(((val) & mask) << shift)
63 
64 struct tegra_adma;
65 
66 /*
67  * struct tegra_adma_chip_data - Tegra chip specific data
68  * @adma_get_burst_config: Function callback used to set DMA burst size.
69  * @global_reg_offset: Register offset of DMA global register.
70  * @global_int_clear: Register offset of DMA global interrupt clear.
71  * @ch_req_tx_shift: Register offset for AHUB transmit channel select.
72  * @ch_req_rx_shift: Register offset for AHUB receive channel select.
73  * @ch_base_offset: Register offset of DMA channel registers.
74  * @ch_fifo_ctrl: Default value for channel FIFO CTRL register.
75  * @ch_req_mask: Mask for Tx or Rx channel select.
76  * @ch_req_max: Maximum number of Tx or Rx channels available.
77  * @ch_reg_size: Size of DMA channel register space.
78  * @nr_channels: Number of DMA channels available.
79  * @ch_fifo_size_mask: Mask for FIFO size field.
80  * @sreq_index_offset: Slave channel index offset.
81  * @has_outstanding_reqs: If DMA channel can have outstanding requests.
82  */
83 struct tegra_adma_chip_data {
84 	unsigned int (*adma_get_burst_config)(unsigned int burst_size);
85 	unsigned int global_reg_offset;
86 	unsigned int global_int_clear;
87 	unsigned int ch_req_tx_shift;
88 	unsigned int ch_req_rx_shift;
89 	unsigned int ch_base_offset;
90 	unsigned int ch_fifo_ctrl;
91 	unsigned int ch_req_mask;
92 	unsigned int ch_req_max;
93 	unsigned int ch_reg_size;
94 	unsigned int nr_channels;
95 	unsigned int ch_fifo_size_mask;
96 	unsigned int sreq_index_offset;
97 	bool has_outstanding_reqs;
98 };
99 
100 /*
101  * struct tegra_adma_chan_regs - Tegra ADMA channel registers
102  */
103 struct tegra_adma_chan_regs {
104 	unsigned int ctrl;
105 	unsigned int config;
106 	unsigned int src_addr;
107 	unsigned int trg_addr;
108 	unsigned int fifo_ctrl;
109 	unsigned int cmd;
110 	unsigned int tc;
111 };
112 
113 /*
114  * struct tegra_adma_desc - Tegra ADMA descriptor to manage transfer requests.
115  */
116 struct tegra_adma_desc {
117 	struct virt_dma_desc		vd;
118 	struct tegra_adma_chan_regs	ch_regs;
119 	size_t				buf_len;
120 	size_t				period_len;
121 	size_t				num_periods;
122 };
123 
124 /*
125  * struct tegra_adma_chan - Tegra ADMA channel information
126  */
127 struct tegra_adma_chan {
128 	struct virt_dma_chan		vc;
129 	struct tegra_adma_desc		*desc;
130 	struct tegra_adma		*tdma;
131 	int				irq;
132 	void __iomem			*chan_addr;
133 
134 	/* Slave channel configuration info */
135 	struct dma_slave_config		sconfig;
136 	enum dma_transfer_direction	sreq_dir;
137 	unsigned int			sreq_index;
138 	bool				sreq_reserved;
139 	struct tegra_adma_chan_regs	ch_regs;
140 
141 	/* Transfer count and position info */
142 	unsigned int			tx_buf_count;
143 	unsigned int			tx_buf_pos;
144 };
145 
146 /*
147  * struct tegra_adma - Tegra ADMA controller information
148  */
149 struct tegra_adma {
150 	struct dma_device		dma_dev;
151 	struct device			*dev;
152 	void __iomem			*base_addr;
153 	struct clk			*ahub_clk;
154 	unsigned int			nr_channels;
155 	unsigned long			rx_requests_reserved;
156 	unsigned long			tx_requests_reserved;
157 
158 	/* Used to store global command register state when suspending */
159 	unsigned int			global_cmd;
160 
161 	const struct tegra_adma_chip_data *cdata;
162 
163 	/* Last member of the structure */
164 	struct tegra_adma_chan		channels[];
165 };
166 
167 static inline void tdma_write(struct tegra_adma *tdma, u32 reg, u32 val)
168 {
169 	writel(val, tdma->base_addr + tdma->cdata->global_reg_offset + reg);
170 }
171 
172 static inline u32 tdma_read(struct tegra_adma *tdma, u32 reg)
173 {
174 	return readl(tdma->base_addr + tdma->cdata->global_reg_offset + reg);
175 }
176 
177 static inline void tdma_ch_write(struct tegra_adma_chan *tdc, u32 reg, u32 val)
178 {
179 	writel(val, tdc->chan_addr + reg);
180 }
181 
182 static inline u32 tdma_ch_read(struct tegra_adma_chan *tdc, u32 reg)
183 {
184 	return readl(tdc->chan_addr + reg);
185 }
186 
187 static inline struct tegra_adma_chan *to_tegra_adma_chan(struct dma_chan *dc)
188 {
189 	return container_of(dc, struct tegra_adma_chan, vc.chan);
190 }
191 
192 static inline struct tegra_adma_desc *to_tegra_adma_desc(
193 		struct dma_async_tx_descriptor *td)
194 {
195 	return container_of(td, struct tegra_adma_desc, vd.tx);
196 }
197 
198 static inline struct device *tdc2dev(struct tegra_adma_chan *tdc)
199 {
200 	return tdc->tdma->dev;
201 }
202 
203 static void tegra_adma_desc_free(struct virt_dma_desc *vd)
204 {
205 	kfree(container_of(vd, struct tegra_adma_desc, vd));
206 }
207 
208 static int tegra_adma_slave_config(struct dma_chan *dc,
209 				   struct dma_slave_config *sconfig)
210 {
211 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
212 
213 	memcpy(&tdc->sconfig, sconfig, sizeof(*sconfig));
214 
215 	return 0;
216 }
217 
218 static int tegra_adma_init(struct tegra_adma *tdma)
219 {
220 	u32 status;
221 	int ret;
222 
223 	/* Clear any interrupts */
224 	tdma_write(tdma, tdma->cdata->ch_base_offset + tdma->cdata->global_int_clear, 0x1);
225 
226 	/* Assert soft reset */
227 	tdma_write(tdma, ADMA_GLOBAL_SOFT_RESET, 0x1);
228 
229 	/* Wait for reset to clear */
230 	ret = readx_poll_timeout(readl,
231 				 tdma->base_addr +
232 				 tdma->cdata->global_reg_offset +
233 				 ADMA_GLOBAL_SOFT_RESET,
234 				 status, status == 0, 20, 10000);
235 	if (ret)
236 		return ret;
237 
238 	/* Enable global ADMA registers */
239 	tdma_write(tdma, ADMA_GLOBAL_CMD, 1);
240 
241 	return 0;
242 }
243 
244 static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
245 				    enum dma_transfer_direction direction)
246 {
247 	struct tegra_adma *tdma = tdc->tdma;
248 	unsigned int sreq_index = tdc->sreq_index;
249 
250 	if (tdc->sreq_reserved)
251 		return tdc->sreq_dir == direction ? 0 : -EINVAL;
252 
253 	if (sreq_index > tdma->cdata->ch_req_max) {
254 		dev_err(tdma->dev, "invalid DMA request\n");
255 		return -EINVAL;
256 	}
257 
258 	switch (direction) {
259 	case DMA_MEM_TO_DEV:
260 		if (test_and_set_bit(sreq_index, &tdma->tx_requests_reserved)) {
261 			dev_err(tdma->dev, "DMA request reserved\n");
262 			return -EINVAL;
263 		}
264 		break;
265 
266 	case DMA_DEV_TO_MEM:
267 		if (test_and_set_bit(sreq_index, &tdma->rx_requests_reserved)) {
268 			dev_err(tdma->dev, "DMA request reserved\n");
269 			return -EINVAL;
270 		}
271 		break;
272 
273 	default:
274 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
275 			 dma_chan_name(&tdc->vc.chan));
276 		return -EINVAL;
277 	}
278 
279 	tdc->sreq_dir = direction;
280 	tdc->sreq_reserved = true;
281 
282 	return 0;
283 }
284 
285 static void tegra_adma_request_free(struct tegra_adma_chan *tdc)
286 {
287 	struct tegra_adma *tdma = tdc->tdma;
288 
289 	if (!tdc->sreq_reserved)
290 		return;
291 
292 	switch (tdc->sreq_dir) {
293 	case DMA_MEM_TO_DEV:
294 		clear_bit(tdc->sreq_index, &tdma->tx_requests_reserved);
295 		break;
296 
297 	case DMA_DEV_TO_MEM:
298 		clear_bit(tdc->sreq_index, &tdma->rx_requests_reserved);
299 		break;
300 
301 	default:
302 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
303 			 dma_chan_name(&tdc->vc.chan));
304 		return;
305 	}
306 
307 	tdc->sreq_reserved = false;
308 }
309 
310 static u32 tegra_adma_irq_status(struct tegra_adma_chan *tdc)
311 {
312 	u32 status = tdma_ch_read(tdc, ADMA_CH_INT_STATUS);
313 
314 	return status & ADMA_CH_INT_STATUS_XFER_DONE;
315 }
316 
317 static u32 tegra_adma_irq_clear(struct tegra_adma_chan *tdc)
318 {
319 	u32 status = tegra_adma_irq_status(tdc);
320 
321 	if (status)
322 		tdma_ch_write(tdc, ADMA_CH_INT_CLEAR, status);
323 
324 	return status;
325 }
326 
327 static void tegra_adma_stop(struct tegra_adma_chan *tdc)
328 {
329 	unsigned int status;
330 
331 	/* Disable ADMA */
332 	tdma_ch_write(tdc, ADMA_CH_CMD, 0);
333 
334 	/* Clear interrupt status */
335 	tegra_adma_irq_clear(tdc);
336 
337 	if (readx_poll_timeout_atomic(readl, tdc->chan_addr + ADMA_CH_STATUS,
338 			status, !(status & ADMA_CH_STATUS_XFER_EN),
339 			20, 10000)) {
340 		dev_err(tdc2dev(tdc), "unable to stop DMA channel\n");
341 		return;
342 	}
343 
344 	kfree(tdc->desc);
345 	tdc->desc = NULL;
346 }
347 
348 static void tegra_adma_start(struct tegra_adma_chan *tdc)
349 {
350 	struct virt_dma_desc *vd = vchan_next_desc(&tdc->vc);
351 	struct tegra_adma_chan_regs *ch_regs;
352 	struct tegra_adma_desc *desc;
353 
354 	if (!vd)
355 		return;
356 
357 	list_del(&vd->node);
358 
359 	desc = to_tegra_adma_desc(&vd->tx);
360 
361 	if (!desc) {
362 		dev_warn(tdc2dev(tdc), "unable to start DMA, no descriptor\n");
363 		return;
364 	}
365 
366 	ch_regs = &desc->ch_regs;
367 
368 	tdc->tx_buf_pos = 0;
369 	tdc->tx_buf_count = 0;
370 	tdma_ch_write(tdc, ADMA_CH_TC, ch_regs->tc);
371 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
372 	tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_regs->src_addr);
373 	tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_regs->trg_addr);
374 	tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_regs->fifo_ctrl);
375 	tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_regs->config);
376 
377 	/* Start ADMA */
378 	tdma_ch_write(tdc, ADMA_CH_CMD, 1);
379 
380 	tdc->desc = desc;
381 }
382 
383 static unsigned int tegra_adma_get_residue(struct tegra_adma_chan *tdc)
384 {
385 	struct tegra_adma_desc *desc = tdc->desc;
386 	unsigned int max = ADMA_CH_XFER_STATUS_COUNT_MASK + 1;
387 	unsigned int pos = tdma_ch_read(tdc, ADMA_CH_XFER_STATUS);
388 	unsigned int periods_remaining;
389 
390 	/*
391 	 * Handle wrap around of buffer count register
392 	 */
393 	if (pos < tdc->tx_buf_pos)
394 		tdc->tx_buf_count += pos + (max - tdc->tx_buf_pos);
395 	else
396 		tdc->tx_buf_count += pos - tdc->tx_buf_pos;
397 
398 	periods_remaining = tdc->tx_buf_count % desc->num_periods;
399 	tdc->tx_buf_pos = pos;
400 
401 	return desc->buf_len - (periods_remaining * desc->period_len);
402 }
403 
404 static irqreturn_t tegra_adma_isr(int irq, void *dev_id)
405 {
406 	struct tegra_adma_chan *tdc = dev_id;
407 	unsigned long status;
408 
409 	spin_lock(&tdc->vc.lock);
410 
411 	status = tegra_adma_irq_clear(tdc);
412 	if (status == 0 || !tdc->desc) {
413 		spin_unlock(&tdc->vc.lock);
414 		return IRQ_NONE;
415 	}
416 
417 	vchan_cyclic_callback(&tdc->desc->vd);
418 
419 	spin_unlock(&tdc->vc.lock);
420 
421 	return IRQ_HANDLED;
422 }
423 
424 static void tegra_adma_issue_pending(struct dma_chan *dc)
425 {
426 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
427 	unsigned long flags;
428 
429 	spin_lock_irqsave(&tdc->vc.lock, flags);
430 
431 	if (vchan_issue_pending(&tdc->vc)) {
432 		if (!tdc->desc)
433 			tegra_adma_start(tdc);
434 	}
435 
436 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
437 }
438 
439 static bool tegra_adma_is_paused(struct tegra_adma_chan *tdc)
440 {
441 	u32 csts;
442 
443 	csts = tdma_ch_read(tdc, ADMA_CH_STATUS);
444 	csts &= ADMA_CH_STATUS_XFER_PAUSED;
445 
446 	return csts ? true : false;
447 }
448 
449 static int tegra_adma_pause(struct dma_chan *dc)
450 {
451 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
452 	struct tegra_adma_desc *desc = tdc->desc;
453 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
454 	int dcnt = 10;
455 
456 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
457 	ch_regs->ctrl |= (1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
458 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
459 
460 	while (dcnt-- && !tegra_adma_is_paused(tdc))
461 		udelay(TEGRA_ADMA_BURST_COMPLETE_TIME);
462 
463 	if (dcnt < 0) {
464 		dev_err(tdc2dev(tdc), "unable to pause DMA channel\n");
465 		return -EBUSY;
466 	}
467 
468 	return 0;
469 }
470 
471 static int tegra_adma_resume(struct dma_chan *dc)
472 {
473 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
474 	struct tegra_adma_desc *desc = tdc->desc;
475 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
476 
477 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
478 	ch_regs->ctrl &= ~(1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
479 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
480 
481 	return 0;
482 }
483 
484 static int tegra_adma_terminate_all(struct dma_chan *dc)
485 {
486 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
487 	unsigned long flags;
488 	LIST_HEAD(head);
489 
490 	spin_lock_irqsave(&tdc->vc.lock, flags);
491 
492 	if (tdc->desc)
493 		tegra_adma_stop(tdc);
494 
495 	tegra_adma_request_free(tdc);
496 	vchan_get_all_descriptors(&tdc->vc, &head);
497 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
498 	vchan_dma_desc_free_list(&tdc->vc, &head);
499 
500 	return 0;
501 }
502 
503 static enum dma_status tegra_adma_tx_status(struct dma_chan *dc,
504 					    dma_cookie_t cookie,
505 					    struct dma_tx_state *txstate)
506 {
507 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
508 	struct tegra_adma_desc *desc;
509 	struct virt_dma_desc *vd;
510 	enum dma_status ret;
511 	unsigned long flags;
512 	unsigned int residual;
513 
514 	ret = dma_cookie_status(dc, cookie, txstate);
515 	if (ret == DMA_COMPLETE || !txstate)
516 		return ret;
517 
518 	spin_lock_irqsave(&tdc->vc.lock, flags);
519 
520 	vd = vchan_find_desc(&tdc->vc, cookie);
521 	if (vd) {
522 		desc = to_tegra_adma_desc(&vd->tx);
523 		residual = desc->ch_regs.tc;
524 	} else if (tdc->desc && tdc->desc->vd.tx.cookie == cookie) {
525 		residual = tegra_adma_get_residue(tdc);
526 	} else {
527 		residual = 0;
528 	}
529 
530 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
531 
532 	dma_set_residue(txstate, residual);
533 
534 	return ret;
535 }
536 
537 static unsigned int tegra210_adma_get_burst_config(unsigned int burst_size)
538 {
539 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
540 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
541 
542 	return fls(burst_size) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
543 }
544 
545 static unsigned int tegra186_adma_get_burst_config(unsigned int burst_size)
546 {
547 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
548 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
549 
550 	return (burst_size - 1) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
551 }
552 
553 static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
554 				      struct tegra_adma_desc *desc,
555 				      dma_addr_t buf_addr,
556 				      enum dma_transfer_direction direction)
557 {
558 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
559 	const struct tegra_adma_chip_data *cdata = tdc->tdma->cdata;
560 	unsigned int burst_size, adma_dir, fifo_size_shift;
561 
562 	if (desc->num_periods > ADMA_CH_CONFIG_MAX_BUFS)
563 		return -EINVAL;
564 
565 	switch (direction) {
566 	case DMA_MEM_TO_DEV:
567 		fifo_size_shift = ADMA_CH_TX_FIFO_SIZE_SHIFT;
568 		adma_dir = ADMA_CH_CTRL_DIR_MEM2AHUB;
569 		burst_size = tdc->sconfig.dst_maxburst;
570 		ch_regs->config = ADMA_CH_CONFIG_SRC_BUF(desc->num_periods - 1);
571 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
572 						      cdata->ch_req_mask,
573 						      cdata->ch_req_tx_shift);
574 		ch_regs->src_addr = buf_addr;
575 		break;
576 
577 	case DMA_DEV_TO_MEM:
578 		fifo_size_shift = ADMA_CH_RX_FIFO_SIZE_SHIFT;
579 		adma_dir = ADMA_CH_CTRL_DIR_AHUB2MEM;
580 		burst_size = tdc->sconfig.src_maxburst;
581 		ch_regs->config = ADMA_CH_CONFIG_TRG_BUF(desc->num_periods - 1);
582 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
583 						      cdata->ch_req_mask,
584 						      cdata->ch_req_rx_shift);
585 		ch_regs->trg_addr = buf_addr;
586 		break;
587 
588 	default:
589 		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
590 		return -EINVAL;
591 	}
592 
593 	ch_regs->ctrl |= ADMA_CH_CTRL_DIR(adma_dir) |
594 			 ADMA_CH_CTRL_MODE_CONTINUOUS |
595 			 ADMA_CH_CTRL_FLOWCTRL_EN;
596 	ch_regs->config |= cdata->adma_get_burst_config(burst_size);
597 	ch_regs->config |= ADMA_CH_CONFIG_WEIGHT_FOR_WRR(1);
598 	if (cdata->has_outstanding_reqs)
599 		ch_regs->config |= TEGRA186_ADMA_CH_CONFIG_OUTSTANDING_REQS(8);
600 
601 	/*
602 	 * 'sreq_index' represents the current ADMAIF channel number and as per
603 	 * HW recommendation its FIFO size should match with the corresponding
604 	 * ADMA channel.
605 	 *
606 	 * ADMA FIFO size is set as per below (based on default ADMAIF channel
607 	 * FIFO sizes):
608 	 *    fifo_size = 0x2 (sreq_index > sreq_index_offset)
609 	 *    fifo_size = 0x3 (sreq_index <= sreq_index_offset)
610 	 *
611 	 */
612 	if (tdc->sreq_index > cdata->sreq_index_offset)
613 		ch_regs->fifo_ctrl =
614 			ADMA_CH_REG_FIELD_VAL(2, cdata->ch_fifo_size_mask,
615 					      fifo_size_shift);
616 	else
617 		ch_regs->fifo_ctrl =
618 			ADMA_CH_REG_FIELD_VAL(3, cdata->ch_fifo_size_mask,
619 					      fifo_size_shift);
620 
621 	ch_regs->tc = desc->period_len & ADMA_CH_TC_COUNT_MASK;
622 
623 	return tegra_adma_request_alloc(tdc, direction);
624 }
625 
626 static struct dma_async_tx_descriptor *tegra_adma_prep_dma_cyclic(
627 	struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
628 	size_t period_len, enum dma_transfer_direction direction,
629 	unsigned long flags)
630 {
631 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
632 	struct tegra_adma_desc *desc = NULL;
633 
634 	if (!buf_len || !period_len || period_len > ADMA_CH_TC_COUNT_MASK) {
635 		dev_err(tdc2dev(tdc), "invalid buffer/period len\n");
636 		return NULL;
637 	}
638 
639 	if (buf_len % period_len) {
640 		dev_err(tdc2dev(tdc), "buf_len not a multiple of period_len\n");
641 		return NULL;
642 	}
643 
644 	if (!IS_ALIGNED(buf_addr, 4)) {
645 		dev_err(tdc2dev(tdc), "invalid buffer alignment\n");
646 		return NULL;
647 	}
648 
649 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
650 	if (!desc)
651 		return NULL;
652 
653 	desc->buf_len = buf_len;
654 	desc->period_len = period_len;
655 	desc->num_periods = buf_len / period_len;
656 
657 	if (tegra_adma_set_xfer_params(tdc, desc, buf_addr, direction)) {
658 		kfree(desc);
659 		return NULL;
660 	}
661 
662 	return vchan_tx_prep(&tdc->vc, &desc->vd, flags);
663 }
664 
665 static int tegra_adma_alloc_chan_resources(struct dma_chan *dc)
666 {
667 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
668 	int ret;
669 
670 	ret = request_irq(tdc->irq, tegra_adma_isr, 0, dma_chan_name(dc), tdc);
671 	if (ret) {
672 		dev_err(tdc2dev(tdc), "failed to get interrupt for %s\n",
673 			dma_chan_name(dc));
674 		return ret;
675 	}
676 
677 	ret = pm_runtime_resume_and_get(tdc2dev(tdc));
678 	if (ret < 0) {
679 		free_irq(tdc->irq, tdc);
680 		return ret;
681 	}
682 
683 	dma_cookie_init(&tdc->vc.chan);
684 
685 	return 0;
686 }
687 
688 static void tegra_adma_free_chan_resources(struct dma_chan *dc)
689 {
690 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
691 
692 	tegra_adma_terminate_all(dc);
693 	vchan_free_chan_resources(&tdc->vc);
694 	tasklet_kill(&tdc->vc.task);
695 	free_irq(tdc->irq, tdc);
696 	pm_runtime_put(tdc2dev(tdc));
697 
698 	tdc->sreq_index = 0;
699 	tdc->sreq_dir = DMA_TRANS_NONE;
700 }
701 
702 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
703 					   struct of_dma *ofdma)
704 {
705 	struct tegra_adma *tdma = ofdma->of_dma_data;
706 	struct tegra_adma_chan *tdc;
707 	struct dma_chan *chan;
708 	unsigned int sreq_index;
709 
710 	if (dma_spec->args_count != 1)
711 		return NULL;
712 
713 	sreq_index = dma_spec->args[0];
714 
715 	if (sreq_index == 0) {
716 		dev_err(tdma->dev, "DMA request must not be 0\n");
717 		return NULL;
718 	}
719 
720 	chan = dma_get_any_slave_channel(&tdma->dma_dev);
721 	if (!chan)
722 		return NULL;
723 
724 	tdc = to_tegra_adma_chan(chan);
725 	tdc->sreq_index = sreq_index;
726 
727 	return chan;
728 }
729 
730 static int __maybe_unused tegra_adma_runtime_suspend(struct device *dev)
731 {
732 	struct tegra_adma *tdma = dev_get_drvdata(dev);
733 	struct tegra_adma_chan_regs *ch_reg;
734 	struct tegra_adma_chan *tdc;
735 	int i;
736 
737 	tdma->global_cmd = tdma_read(tdma, ADMA_GLOBAL_CMD);
738 	if (!tdma->global_cmd)
739 		goto clk_disable;
740 
741 	for (i = 0; i < tdma->nr_channels; i++) {
742 		tdc = &tdma->channels[i];
743 		ch_reg = &tdc->ch_regs;
744 		ch_reg->cmd = tdma_ch_read(tdc, ADMA_CH_CMD);
745 		/* skip if channel is not active */
746 		if (!ch_reg->cmd)
747 			continue;
748 		ch_reg->tc = tdma_ch_read(tdc, ADMA_CH_TC);
749 		ch_reg->src_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_SRC_ADDR);
750 		ch_reg->trg_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_TRG_ADDR);
751 		ch_reg->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
752 		ch_reg->fifo_ctrl = tdma_ch_read(tdc, ADMA_CH_FIFO_CTRL);
753 		ch_reg->config = tdma_ch_read(tdc, ADMA_CH_CONFIG);
754 	}
755 
756 clk_disable:
757 	clk_disable_unprepare(tdma->ahub_clk);
758 
759 	return 0;
760 }
761 
762 static int __maybe_unused tegra_adma_runtime_resume(struct device *dev)
763 {
764 	struct tegra_adma *tdma = dev_get_drvdata(dev);
765 	struct tegra_adma_chan_regs *ch_reg;
766 	struct tegra_adma_chan *tdc;
767 	int ret, i;
768 
769 	ret = clk_prepare_enable(tdma->ahub_clk);
770 	if (ret) {
771 		dev_err(dev, "ahub clk_enable failed: %d\n", ret);
772 		return ret;
773 	}
774 	tdma_write(tdma, ADMA_GLOBAL_CMD, tdma->global_cmd);
775 
776 	if (!tdma->global_cmd)
777 		return 0;
778 
779 	for (i = 0; i < tdma->nr_channels; i++) {
780 		tdc = &tdma->channels[i];
781 		ch_reg = &tdc->ch_regs;
782 		/* skip if channel was not active earlier */
783 		if (!ch_reg->cmd)
784 			continue;
785 		tdma_ch_write(tdc, ADMA_CH_TC, ch_reg->tc);
786 		tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_reg->src_addr);
787 		tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_reg->trg_addr);
788 		tdma_ch_write(tdc, ADMA_CH_CTRL, ch_reg->ctrl);
789 		tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_reg->fifo_ctrl);
790 		tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_reg->config);
791 		tdma_ch_write(tdc, ADMA_CH_CMD, ch_reg->cmd);
792 	}
793 
794 	return 0;
795 }
796 
797 static const struct tegra_adma_chip_data tegra210_chip_data = {
798 	.adma_get_burst_config  = tegra210_adma_get_burst_config,
799 	.global_reg_offset	= 0xc00,
800 	.global_int_clear	= 0x20,
801 	.ch_req_tx_shift	= 28,
802 	.ch_req_rx_shift	= 24,
803 	.ch_base_offset		= 0,
804 	.ch_req_mask		= 0xf,
805 	.ch_req_max		= 10,
806 	.ch_reg_size		= 0x80,
807 	.nr_channels		= 22,
808 	.ch_fifo_size_mask	= 0xf,
809 	.sreq_index_offset	= 2,
810 	.has_outstanding_reqs	= false,
811 };
812 
813 static const struct tegra_adma_chip_data tegra186_chip_data = {
814 	.adma_get_burst_config  = tegra186_adma_get_burst_config,
815 	.global_reg_offset	= 0,
816 	.global_int_clear	= 0x402c,
817 	.ch_req_tx_shift	= 27,
818 	.ch_req_rx_shift	= 22,
819 	.ch_base_offset		= 0x10000,
820 	.ch_req_mask		= 0x1f,
821 	.ch_req_max		= 20,
822 	.ch_reg_size		= 0x100,
823 	.nr_channels		= 32,
824 	.ch_fifo_size_mask	= 0x1f,
825 	.sreq_index_offset	= 4,
826 	.has_outstanding_reqs	= true,
827 };
828 
829 static const struct of_device_id tegra_adma_of_match[] = {
830 	{ .compatible = "nvidia,tegra210-adma", .data = &tegra210_chip_data },
831 	{ .compatible = "nvidia,tegra186-adma", .data = &tegra186_chip_data },
832 	{ },
833 };
834 MODULE_DEVICE_TABLE(of, tegra_adma_of_match);
835 
836 static int tegra_adma_probe(struct platform_device *pdev)
837 {
838 	const struct tegra_adma_chip_data *cdata;
839 	struct tegra_adma *tdma;
840 	struct resource	*res;
841 	int ret, i;
842 
843 	cdata = of_device_get_match_data(&pdev->dev);
844 	if (!cdata) {
845 		dev_err(&pdev->dev, "device match data not found\n");
846 		return -ENODEV;
847 	}
848 
849 	tdma = devm_kzalloc(&pdev->dev,
850 			    struct_size(tdma, channels, cdata->nr_channels),
851 			    GFP_KERNEL);
852 	if (!tdma)
853 		return -ENOMEM;
854 
855 	tdma->dev = &pdev->dev;
856 	tdma->cdata = cdata;
857 	tdma->nr_channels = cdata->nr_channels;
858 	platform_set_drvdata(pdev, tdma);
859 
860 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
861 	tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
862 	if (IS_ERR(tdma->base_addr))
863 		return PTR_ERR(tdma->base_addr);
864 
865 	tdma->ahub_clk = devm_clk_get(&pdev->dev, "d_audio");
866 	if (IS_ERR(tdma->ahub_clk)) {
867 		dev_err(&pdev->dev, "Error: Missing ahub controller clock\n");
868 		return PTR_ERR(tdma->ahub_clk);
869 	}
870 
871 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
872 	for (i = 0; i < tdma->nr_channels; i++) {
873 		struct tegra_adma_chan *tdc = &tdma->channels[i];
874 
875 		tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
876 				 + (cdata->ch_reg_size * i);
877 
878 		tdc->irq = of_irq_get(pdev->dev.of_node, i);
879 		if (tdc->irq <= 0) {
880 			ret = tdc->irq ?: -ENXIO;
881 			goto irq_dispose;
882 		}
883 
884 		vchan_init(&tdc->vc, &tdma->dma_dev);
885 		tdc->vc.desc_free = tegra_adma_desc_free;
886 		tdc->tdma = tdma;
887 	}
888 
889 	pm_runtime_enable(&pdev->dev);
890 
891 	ret = pm_runtime_resume_and_get(&pdev->dev);
892 	if (ret < 0)
893 		goto rpm_disable;
894 
895 	ret = tegra_adma_init(tdma);
896 	if (ret)
897 		goto rpm_put;
898 
899 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
900 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
901 	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
902 
903 	tdma->dma_dev.dev = &pdev->dev;
904 	tdma->dma_dev.device_alloc_chan_resources =
905 					tegra_adma_alloc_chan_resources;
906 	tdma->dma_dev.device_free_chan_resources =
907 					tegra_adma_free_chan_resources;
908 	tdma->dma_dev.device_issue_pending = tegra_adma_issue_pending;
909 	tdma->dma_dev.device_prep_dma_cyclic = tegra_adma_prep_dma_cyclic;
910 	tdma->dma_dev.device_config = tegra_adma_slave_config;
911 	tdma->dma_dev.device_tx_status = tegra_adma_tx_status;
912 	tdma->dma_dev.device_terminate_all = tegra_adma_terminate_all;
913 	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
914 	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
915 	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
916 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
917 	tdma->dma_dev.device_pause = tegra_adma_pause;
918 	tdma->dma_dev.device_resume = tegra_adma_resume;
919 
920 	ret = dma_async_device_register(&tdma->dma_dev);
921 	if (ret < 0) {
922 		dev_err(&pdev->dev, "ADMA registration failed: %d\n", ret);
923 		goto rpm_put;
924 	}
925 
926 	ret = of_dma_controller_register(pdev->dev.of_node,
927 					 tegra_dma_of_xlate, tdma);
928 	if (ret < 0) {
929 		dev_err(&pdev->dev, "ADMA OF registration failed %d\n", ret);
930 		goto dma_remove;
931 	}
932 
933 	pm_runtime_put(&pdev->dev);
934 
935 	dev_info(&pdev->dev, "Tegra210 ADMA driver registered %d channels\n",
936 		 tdma->nr_channels);
937 
938 	return 0;
939 
940 dma_remove:
941 	dma_async_device_unregister(&tdma->dma_dev);
942 rpm_put:
943 	pm_runtime_put_sync(&pdev->dev);
944 rpm_disable:
945 	pm_runtime_disable(&pdev->dev);
946 irq_dispose:
947 	while (--i >= 0)
948 		irq_dispose_mapping(tdma->channels[i].irq);
949 
950 	return ret;
951 }
952 
953 static int tegra_adma_remove(struct platform_device *pdev)
954 {
955 	struct tegra_adma *tdma = platform_get_drvdata(pdev);
956 	int i;
957 
958 	of_dma_controller_free(pdev->dev.of_node);
959 	dma_async_device_unregister(&tdma->dma_dev);
960 
961 	for (i = 0; i < tdma->nr_channels; ++i)
962 		irq_dispose_mapping(tdma->channels[i].irq);
963 
964 	pm_runtime_disable(&pdev->dev);
965 
966 	return 0;
967 }
968 
969 static const struct dev_pm_ops tegra_adma_dev_pm_ops = {
970 	SET_RUNTIME_PM_OPS(tegra_adma_runtime_suspend,
971 			   tegra_adma_runtime_resume, NULL)
972 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
973 				     pm_runtime_force_resume)
974 };
975 
976 static struct platform_driver tegra_admac_driver = {
977 	.driver = {
978 		.name	= "tegra-adma",
979 		.pm	= &tegra_adma_dev_pm_ops,
980 		.of_match_table = tegra_adma_of_match,
981 	},
982 	.probe		= tegra_adma_probe,
983 	.remove		= tegra_adma_remove,
984 };
985 
986 module_platform_driver(tegra_admac_driver);
987 
988 MODULE_ALIAS("platform:tegra210-adma");
989 MODULE_DESCRIPTION("NVIDIA Tegra ADMA driver");
990 MODULE_AUTHOR("Dara Ramesh <dramesh@nvidia.com>");
991 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
992 MODULE_LICENSE("GPL v2");
993