xref: /openbmc/linux/drivers/dma/tegra210-adma.c (revision 4419617e)
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 
44 #define ADMA_CH_FIFO_CTRL				0x2c
45 #define TEGRA210_ADMA_CH_FIFO_CTRL_OFLWTHRES(val)	(((val) & 0xf) << 24)
46 #define TEGRA210_ADMA_CH_FIFO_CTRL_STRVTHRES(val)	(((val) & 0xf) << 16)
47 #define TEGRA210_ADMA_CH_FIFO_CTRL_TXSIZE(val)		(((val) & 0xf) << 8)
48 #define TEGRA210_ADMA_CH_FIFO_CTRL_RXSIZE(val)		((val) & 0xf)
49 #define TEGRA186_ADMA_CH_FIFO_CTRL_OFLWTHRES(val)	(((val) & 0x1f) << 24)
50 #define TEGRA186_ADMA_CH_FIFO_CTRL_STRVTHRES(val)	(((val) & 0x1f) << 16)
51 #define TEGRA186_ADMA_CH_FIFO_CTRL_TXSIZE(val)		(((val) & 0x1f) << 8)
52 #define TEGRA186_ADMA_CH_FIFO_CTRL_RXSIZE(val)		((val) & 0x1f)
53 
54 #define ADMA_CH_LOWER_SRC_ADDR				0x34
55 #define ADMA_CH_LOWER_TRG_ADDR				0x3c
56 #define ADMA_CH_TC					0x44
57 #define ADMA_CH_TC_COUNT_MASK				0x3ffffffc
58 
59 #define ADMA_CH_XFER_STATUS				0x54
60 #define ADMA_CH_XFER_STATUS_COUNT_MASK			0xffff
61 
62 #define ADMA_GLOBAL_CMD					0x00
63 #define ADMA_GLOBAL_SOFT_RESET				0x04
64 
65 #define TEGRA_ADMA_BURST_COMPLETE_TIME			20
66 
67 #define TEGRA210_FIFO_CTRL_DEFAULT (TEGRA210_ADMA_CH_FIFO_CTRL_OFLWTHRES(1) | \
68 				    TEGRA210_ADMA_CH_FIFO_CTRL_STRVTHRES(1) | \
69 				    TEGRA210_ADMA_CH_FIFO_CTRL_TXSIZE(3)    | \
70 				    TEGRA210_ADMA_CH_FIFO_CTRL_RXSIZE(3))
71 
72 #define TEGRA186_FIFO_CTRL_DEFAULT (TEGRA186_ADMA_CH_FIFO_CTRL_OFLWTHRES(1) | \
73 				    TEGRA186_ADMA_CH_FIFO_CTRL_STRVTHRES(1) | \
74 				    TEGRA186_ADMA_CH_FIFO_CTRL_TXSIZE(3)    | \
75 				    TEGRA186_ADMA_CH_FIFO_CTRL_RXSIZE(3))
76 
77 #define ADMA_CH_REG_FIELD_VAL(val, mask, shift)	(((val) & mask) << shift)
78 
79 struct tegra_adma;
80 
81 /*
82  * struct tegra_adma_chip_data - Tegra chip specific data
83  * @global_reg_offset: Register offset of DMA global register.
84  * @global_int_clear: Register offset of DMA global interrupt clear.
85  * @ch_req_tx_shift: Register offset for AHUB transmit channel select.
86  * @ch_req_rx_shift: Register offset for AHUB receive channel select.
87  * @ch_base_offset: Register offset of DMA channel registers.
88  * @ch_fifo_ctrl: Default value for channel FIFO CTRL register.
89  * @ch_req_mask: Mask for Tx or Rx channel select.
90  * @ch_req_max: Maximum number of Tx or Rx channels available.
91  * @ch_reg_size: Size of DMA channel register space.
92  * @nr_channels: Number of DMA channels available.
93  */
94 struct tegra_adma_chip_data {
95 	unsigned int (*adma_get_burst_config)(unsigned int burst_size);
96 	unsigned int global_reg_offset;
97 	unsigned int global_int_clear;
98 	unsigned int ch_req_tx_shift;
99 	unsigned int ch_req_rx_shift;
100 	unsigned int ch_base_offset;
101 	unsigned int ch_fifo_ctrl;
102 	unsigned int ch_req_mask;
103 	unsigned int ch_req_max;
104 	unsigned int ch_reg_size;
105 	unsigned int nr_channels;
106 };
107 
108 /*
109  * struct tegra_adma_chan_regs - Tegra ADMA channel registers
110  */
111 struct tegra_adma_chan_regs {
112 	unsigned int ctrl;
113 	unsigned int config;
114 	unsigned int src_addr;
115 	unsigned int trg_addr;
116 	unsigned int fifo_ctrl;
117 	unsigned int cmd;
118 	unsigned int tc;
119 };
120 
121 /*
122  * struct tegra_adma_desc - Tegra ADMA descriptor to manage transfer requests.
123  */
124 struct tegra_adma_desc {
125 	struct virt_dma_desc		vd;
126 	struct tegra_adma_chan_regs	ch_regs;
127 	size_t				buf_len;
128 	size_t				period_len;
129 	size_t				num_periods;
130 };
131 
132 /*
133  * struct tegra_adma_chan - Tegra ADMA channel information
134  */
135 struct tegra_adma_chan {
136 	struct virt_dma_chan		vc;
137 	struct tegra_adma_desc		*desc;
138 	struct tegra_adma		*tdma;
139 	int				irq;
140 	void __iomem			*chan_addr;
141 
142 	/* Slave channel configuration info */
143 	struct dma_slave_config		sconfig;
144 	enum dma_transfer_direction	sreq_dir;
145 	unsigned int			sreq_index;
146 	bool				sreq_reserved;
147 	struct tegra_adma_chan_regs	ch_regs;
148 
149 	/* Transfer count and position info */
150 	unsigned int			tx_buf_count;
151 	unsigned int			tx_buf_pos;
152 };
153 
154 /*
155  * struct tegra_adma - Tegra ADMA controller information
156  */
157 struct tegra_adma {
158 	struct dma_device		dma_dev;
159 	struct device			*dev;
160 	void __iomem			*base_addr;
161 	struct clk			*ahub_clk;
162 	unsigned int			nr_channels;
163 	unsigned long			rx_requests_reserved;
164 	unsigned long			tx_requests_reserved;
165 
166 	/* Used to store global command register state when suspending */
167 	unsigned int			global_cmd;
168 
169 	const struct tegra_adma_chip_data *cdata;
170 
171 	/* Last member of the structure */
172 	struct tegra_adma_chan		channels[0];
173 };
174 
175 static inline void tdma_write(struct tegra_adma *tdma, u32 reg, u32 val)
176 {
177 	writel(val, tdma->base_addr + tdma->cdata->global_reg_offset + reg);
178 }
179 
180 static inline u32 tdma_read(struct tegra_adma *tdma, u32 reg)
181 {
182 	return readl(tdma->base_addr + tdma->cdata->global_reg_offset + reg);
183 }
184 
185 static inline void tdma_ch_write(struct tegra_adma_chan *tdc, u32 reg, u32 val)
186 {
187 	writel(val, tdc->chan_addr + reg);
188 }
189 
190 static inline u32 tdma_ch_read(struct tegra_adma_chan *tdc, u32 reg)
191 {
192 	return readl(tdc->chan_addr + reg);
193 }
194 
195 static inline struct tegra_adma_chan *to_tegra_adma_chan(struct dma_chan *dc)
196 {
197 	return container_of(dc, struct tegra_adma_chan, vc.chan);
198 }
199 
200 static inline struct tegra_adma_desc *to_tegra_adma_desc(
201 		struct dma_async_tx_descriptor *td)
202 {
203 	return container_of(td, struct tegra_adma_desc, vd.tx);
204 }
205 
206 static inline struct device *tdc2dev(struct tegra_adma_chan *tdc)
207 {
208 	return tdc->tdma->dev;
209 }
210 
211 static void tegra_adma_desc_free(struct virt_dma_desc *vd)
212 {
213 	kfree(container_of(vd, struct tegra_adma_desc, vd));
214 }
215 
216 static int tegra_adma_slave_config(struct dma_chan *dc,
217 				   struct dma_slave_config *sconfig)
218 {
219 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
220 
221 	memcpy(&tdc->sconfig, sconfig, sizeof(*sconfig));
222 
223 	return 0;
224 }
225 
226 static int tegra_adma_init(struct tegra_adma *tdma)
227 {
228 	u32 status;
229 	int ret;
230 
231 	/* Clear any interrupts */
232 	tdma_write(tdma, tdma->cdata->global_int_clear, 0x1);
233 
234 	/* Assert soft reset */
235 	tdma_write(tdma, ADMA_GLOBAL_SOFT_RESET, 0x1);
236 
237 	/* Wait for reset to clear */
238 	ret = readx_poll_timeout(readl,
239 				 tdma->base_addr +
240 				 tdma->cdata->global_reg_offset +
241 				 ADMA_GLOBAL_SOFT_RESET,
242 				 status, status == 0, 20, 10000);
243 	if (ret)
244 		return ret;
245 
246 	/* Enable global ADMA registers */
247 	tdma_write(tdma, ADMA_GLOBAL_CMD, 1);
248 
249 	return 0;
250 }
251 
252 static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
253 				    enum dma_transfer_direction direction)
254 {
255 	struct tegra_adma *tdma = tdc->tdma;
256 	unsigned int sreq_index = tdc->sreq_index;
257 
258 	if (tdc->sreq_reserved)
259 		return tdc->sreq_dir == direction ? 0 : -EINVAL;
260 
261 	if (sreq_index > tdma->cdata->ch_req_max) {
262 		dev_err(tdma->dev, "invalid DMA request\n");
263 		return -EINVAL;
264 	}
265 
266 	switch (direction) {
267 	case DMA_MEM_TO_DEV:
268 		if (test_and_set_bit(sreq_index, &tdma->tx_requests_reserved)) {
269 			dev_err(tdma->dev, "DMA request reserved\n");
270 			return -EINVAL;
271 		}
272 		break;
273 
274 	case DMA_DEV_TO_MEM:
275 		if (test_and_set_bit(sreq_index, &tdma->rx_requests_reserved)) {
276 			dev_err(tdma->dev, "DMA request reserved\n");
277 			return -EINVAL;
278 		}
279 		break;
280 
281 	default:
282 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
283 			 dma_chan_name(&tdc->vc.chan));
284 		return -EINVAL;
285 	}
286 
287 	tdc->sreq_dir = direction;
288 	tdc->sreq_reserved = true;
289 
290 	return 0;
291 }
292 
293 static void tegra_adma_request_free(struct tegra_adma_chan *tdc)
294 {
295 	struct tegra_adma *tdma = tdc->tdma;
296 
297 	if (!tdc->sreq_reserved)
298 		return;
299 
300 	switch (tdc->sreq_dir) {
301 	case DMA_MEM_TO_DEV:
302 		clear_bit(tdc->sreq_index, &tdma->tx_requests_reserved);
303 		break;
304 
305 	case DMA_DEV_TO_MEM:
306 		clear_bit(tdc->sreq_index, &tdma->rx_requests_reserved);
307 		break;
308 
309 	default:
310 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
311 			 dma_chan_name(&tdc->vc.chan));
312 		return;
313 	}
314 
315 	tdc->sreq_reserved = false;
316 }
317 
318 static u32 tegra_adma_irq_status(struct tegra_adma_chan *tdc)
319 {
320 	u32 status = tdma_ch_read(tdc, ADMA_CH_INT_STATUS);
321 
322 	return status & ADMA_CH_INT_STATUS_XFER_DONE;
323 }
324 
325 static u32 tegra_adma_irq_clear(struct tegra_adma_chan *tdc)
326 {
327 	u32 status = tegra_adma_irq_status(tdc);
328 
329 	if (status)
330 		tdma_ch_write(tdc, ADMA_CH_INT_CLEAR, status);
331 
332 	return status;
333 }
334 
335 static void tegra_adma_stop(struct tegra_adma_chan *tdc)
336 {
337 	unsigned int status;
338 
339 	/* Disable ADMA */
340 	tdma_ch_write(tdc, ADMA_CH_CMD, 0);
341 
342 	/* Clear interrupt status */
343 	tegra_adma_irq_clear(tdc);
344 
345 	if (readx_poll_timeout_atomic(readl, tdc->chan_addr + ADMA_CH_STATUS,
346 			status, !(status & ADMA_CH_STATUS_XFER_EN),
347 			20, 10000)) {
348 		dev_err(tdc2dev(tdc), "unable to stop DMA channel\n");
349 		return;
350 	}
351 
352 	kfree(tdc->desc);
353 	tdc->desc = NULL;
354 }
355 
356 static void tegra_adma_start(struct tegra_adma_chan *tdc)
357 {
358 	struct virt_dma_desc *vd = vchan_next_desc(&tdc->vc);
359 	struct tegra_adma_chan_regs *ch_regs;
360 	struct tegra_adma_desc *desc;
361 
362 	if (!vd)
363 		return;
364 
365 	list_del(&vd->node);
366 
367 	desc = to_tegra_adma_desc(&vd->tx);
368 
369 	if (!desc) {
370 		dev_warn(tdc2dev(tdc), "unable to start DMA, no descriptor\n");
371 		return;
372 	}
373 
374 	ch_regs = &desc->ch_regs;
375 
376 	tdc->tx_buf_pos = 0;
377 	tdc->tx_buf_count = 0;
378 	tdma_ch_write(tdc, ADMA_CH_TC, ch_regs->tc);
379 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
380 	tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_regs->src_addr);
381 	tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_regs->trg_addr);
382 	tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_regs->fifo_ctrl);
383 	tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_regs->config);
384 
385 	/* Start ADMA */
386 	tdma_ch_write(tdc, ADMA_CH_CMD, 1);
387 
388 	tdc->desc = desc;
389 }
390 
391 static unsigned int tegra_adma_get_residue(struct tegra_adma_chan *tdc)
392 {
393 	struct tegra_adma_desc *desc = tdc->desc;
394 	unsigned int max = ADMA_CH_XFER_STATUS_COUNT_MASK + 1;
395 	unsigned int pos = tdma_ch_read(tdc, ADMA_CH_XFER_STATUS);
396 	unsigned int periods_remaining;
397 
398 	/*
399 	 * Handle wrap around of buffer count register
400 	 */
401 	if (pos < tdc->tx_buf_pos)
402 		tdc->tx_buf_count += pos + (max - tdc->tx_buf_pos);
403 	else
404 		tdc->tx_buf_count += pos - tdc->tx_buf_pos;
405 
406 	periods_remaining = tdc->tx_buf_count % desc->num_periods;
407 	tdc->tx_buf_pos = pos;
408 
409 	return desc->buf_len - (periods_remaining * desc->period_len);
410 }
411 
412 static irqreturn_t tegra_adma_isr(int irq, void *dev_id)
413 {
414 	struct tegra_adma_chan *tdc = dev_id;
415 	unsigned long status;
416 	unsigned long flags;
417 
418 	spin_lock_irqsave(&tdc->vc.lock, flags);
419 
420 	status = tegra_adma_irq_clear(tdc);
421 	if (status == 0 || !tdc->desc) {
422 		spin_unlock_irqrestore(&tdc->vc.lock, flags);
423 		return IRQ_NONE;
424 	}
425 
426 	vchan_cyclic_callback(&tdc->desc->vd);
427 
428 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
429 
430 	return IRQ_HANDLED;
431 }
432 
433 static void tegra_adma_issue_pending(struct dma_chan *dc)
434 {
435 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
436 	unsigned long flags;
437 
438 	spin_lock_irqsave(&tdc->vc.lock, flags);
439 
440 	if (vchan_issue_pending(&tdc->vc)) {
441 		if (!tdc->desc)
442 			tegra_adma_start(tdc);
443 	}
444 
445 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
446 }
447 
448 static bool tegra_adma_is_paused(struct tegra_adma_chan *tdc)
449 {
450 	u32 csts;
451 
452 	csts = tdma_ch_read(tdc, ADMA_CH_STATUS);
453 	csts &= ADMA_CH_STATUS_XFER_PAUSED;
454 
455 	return csts ? true : false;
456 }
457 
458 static int tegra_adma_pause(struct dma_chan *dc)
459 {
460 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
461 	struct tegra_adma_desc *desc = tdc->desc;
462 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
463 	int dcnt = 10;
464 
465 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
466 	ch_regs->ctrl |= (1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
467 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
468 
469 	while (dcnt-- && !tegra_adma_is_paused(tdc))
470 		udelay(TEGRA_ADMA_BURST_COMPLETE_TIME);
471 
472 	if (dcnt < 0) {
473 		dev_err(tdc2dev(tdc), "unable to pause DMA channel\n");
474 		return -EBUSY;
475 	}
476 
477 	return 0;
478 }
479 
480 static int tegra_adma_resume(struct dma_chan *dc)
481 {
482 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
483 	struct tegra_adma_desc *desc = tdc->desc;
484 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
485 
486 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
487 	ch_regs->ctrl &= ~(1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
488 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
489 
490 	return 0;
491 }
492 
493 static int tegra_adma_terminate_all(struct dma_chan *dc)
494 {
495 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
496 	unsigned long flags;
497 	LIST_HEAD(head);
498 
499 	spin_lock_irqsave(&tdc->vc.lock, flags);
500 
501 	if (tdc->desc)
502 		tegra_adma_stop(tdc);
503 
504 	tegra_adma_request_free(tdc);
505 	vchan_get_all_descriptors(&tdc->vc, &head);
506 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
507 	vchan_dma_desc_free_list(&tdc->vc, &head);
508 
509 	return 0;
510 }
511 
512 static enum dma_status tegra_adma_tx_status(struct dma_chan *dc,
513 					    dma_cookie_t cookie,
514 					    struct dma_tx_state *txstate)
515 {
516 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
517 	struct tegra_adma_desc *desc;
518 	struct virt_dma_desc *vd;
519 	enum dma_status ret;
520 	unsigned long flags;
521 	unsigned int residual;
522 
523 	ret = dma_cookie_status(dc, cookie, txstate);
524 	if (ret == DMA_COMPLETE || !txstate)
525 		return ret;
526 
527 	spin_lock_irqsave(&tdc->vc.lock, flags);
528 
529 	vd = vchan_find_desc(&tdc->vc, cookie);
530 	if (vd) {
531 		desc = to_tegra_adma_desc(&vd->tx);
532 		residual = desc->ch_regs.tc;
533 	} else if (tdc->desc && tdc->desc->vd.tx.cookie == cookie) {
534 		residual = tegra_adma_get_residue(tdc);
535 	} else {
536 		residual = 0;
537 	}
538 
539 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
540 
541 	dma_set_residue(txstate, residual);
542 
543 	return ret;
544 }
545 
546 static unsigned int tegra210_adma_get_burst_config(unsigned int burst_size)
547 {
548 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
549 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
550 
551 	return fls(burst_size) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
552 }
553 
554 static unsigned int tegra186_adma_get_burst_config(unsigned int burst_size)
555 {
556 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
557 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
558 
559 	return (burst_size - 1) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
560 }
561 
562 static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
563 				      struct tegra_adma_desc *desc,
564 				      dma_addr_t buf_addr,
565 				      enum dma_transfer_direction direction)
566 {
567 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
568 	const struct tegra_adma_chip_data *cdata = tdc->tdma->cdata;
569 	unsigned int burst_size, adma_dir;
570 
571 	if (desc->num_periods > ADMA_CH_CONFIG_MAX_BUFS)
572 		return -EINVAL;
573 
574 	switch (direction) {
575 	case DMA_MEM_TO_DEV:
576 		adma_dir = ADMA_CH_CTRL_DIR_MEM2AHUB;
577 		burst_size = tdc->sconfig.dst_maxburst;
578 		ch_regs->config = ADMA_CH_CONFIG_SRC_BUF(desc->num_periods - 1);
579 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
580 						      cdata->ch_req_mask,
581 						      cdata->ch_req_tx_shift);
582 		ch_regs->src_addr = buf_addr;
583 		break;
584 
585 	case DMA_DEV_TO_MEM:
586 		adma_dir = ADMA_CH_CTRL_DIR_AHUB2MEM;
587 		burst_size = tdc->sconfig.src_maxburst;
588 		ch_regs->config = ADMA_CH_CONFIG_TRG_BUF(desc->num_periods - 1);
589 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
590 						      cdata->ch_req_mask,
591 						      cdata->ch_req_rx_shift);
592 		ch_regs->trg_addr = buf_addr;
593 		break;
594 
595 	default:
596 		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
597 		return -EINVAL;
598 	}
599 
600 	ch_regs->ctrl |= ADMA_CH_CTRL_DIR(adma_dir) |
601 			 ADMA_CH_CTRL_MODE_CONTINUOUS |
602 			 ADMA_CH_CTRL_FLOWCTRL_EN;
603 	ch_regs->config |= cdata->adma_get_burst_config(burst_size);
604 	ch_regs->config |= ADMA_CH_CONFIG_WEIGHT_FOR_WRR(1);
605 	ch_regs->fifo_ctrl = cdata->ch_fifo_ctrl;
606 	ch_regs->tc = desc->period_len & ADMA_CH_TC_COUNT_MASK;
607 
608 	return tegra_adma_request_alloc(tdc, direction);
609 }
610 
611 static struct dma_async_tx_descriptor *tegra_adma_prep_dma_cyclic(
612 	struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
613 	size_t period_len, enum dma_transfer_direction direction,
614 	unsigned long flags)
615 {
616 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
617 	struct tegra_adma_desc *desc = NULL;
618 
619 	if (!buf_len || !period_len || period_len > ADMA_CH_TC_COUNT_MASK) {
620 		dev_err(tdc2dev(tdc), "invalid buffer/period len\n");
621 		return NULL;
622 	}
623 
624 	if (buf_len % period_len) {
625 		dev_err(tdc2dev(tdc), "buf_len not a multiple of period_len\n");
626 		return NULL;
627 	}
628 
629 	if (!IS_ALIGNED(buf_addr, 4)) {
630 		dev_err(tdc2dev(tdc), "invalid buffer alignment\n");
631 		return NULL;
632 	}
633 
634 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
635 	if (!desc)
636 		return NULL;
637 
638 	desc->buf_len = buf_len;
639 	desc->period_len = period_len;
640 	desc->num_periods = buf_len / period_len;
641 
642 	if (tegra_adma_set_xfer_params(tdc, desc, buf_addr, direction)) {
643 		kfree(desc);
644 		return NULL;
645 	}
646 
647 	return vchan_tx_prep(&tdc->vc, &desc->vd, flags);
648 }
649 
650 static int tegra_adma_alloc_chan_resources(struct dma_chan *dc)
651 {
652 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
653 	int ret;
654 
655 	ret = request_irq(tdc->irq, tegra_adma_isr, 0, dma_chan_name(dc), tdc);
656 	if (ret) {
657 		dev_err(tdc2dev(tdc), "failed to get interrupt for %s\n",
658 			dma_chan_name(dc));
659 		return ret;
660 	}
661 
662 	ret = pm_runtime_get_sync(tdc2dev(tdc));
663 	if (ret < 0) {
664 		free_irq(tdc->irq, tdc);
665 		return ret;
666 	}
667 
668 	dma_cookie_init(&tdc->vc.chan);
669 
670 	return 0;
671 }
672 
673 static void tegra_adma_free_chan_resources(struct dma_chan *dc)
674 {
675 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
676 
677 	tegra_adma_terminate_all(dc);
678 	vchan_free_chan_resources(&tdc->vc);
679 	tasklet_kill(&tdc->vc.task);
680 	free_irq(tdc->irq, tdc);
681 	pm_runtime_put(tdc2dev(tdc));
682 
683 	tdc->sreq_index = 0;
684 	tdc->sreq_dir = DMA_TRANS_NONE;
685 }
686 
687 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
688 					   struct of_dma *ofdma)
689 {
690 	struct tegra_adma *tdma = ofdma->of_dma_data;
691 	struct tegra_adma_chan *tdc;
692 	struct dma_chan *chan;
693 	unsigned int sreq_index;
694 
695 	if (dma_spec->args_count != 1)
696 		return NULL;
697 
698 	sreq_index = dma_spec->args[0];
699 
700 	if (sreq_index == 0) {
701 		dev_err(tdma->dev, "DMA request must not be 0\n");
702 		return NULL;
703 	}
704 
705 	chan = dma_get_any_slave_channel(&tdma->dma_dev);
706 	if (!chan)
707 		return NULL;
708 
709 	tdc = to_tegra_adma_chan(chan);
710 	tdc->sreq_index = sreq_index;
711 
712 	return chan;
713 }
714 
715 static int tegra_adma_runtime_suspend(struct device *dev)
716 {
717 	struct tegra_adma *tdma = dev_get_drvdata(dev);
718 	struct tegra_adma_chan_regs *ch_reg;
719 	struct tegra_adma_chan *tdc;
720 	int i;
721 
722 	tdma->global_cmd = tdma_read(tdma, ADMA_GLOBAL_CMD);
723 	if (!tdma->global_cmd)
724 		goto clk_disable;
725 
726 	for (i = 0; i < tdma->nr_channels; i++) {
727 		tdc = &tdma->channels[i];
728 		ch_reg = &tdc->ch_regs;
729 		ch_reg->cmd = tdma_ch_read(tdc, ADMA_CH_CMD);
730 		/* skip if channel is not active */
731 		if (!ch_reg->cmd)
732 			continue;
733 		ch_reg->tc = tdma_ch_read(tdc, ADMA_CH_TC);
734 		ch_reg->src_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_SRC_ADDR);
735 		ch_reg->trg_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_TRG_ADDR);
736 		ch_reg->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
737 		ch_reg->fifo_ctrl = tdma_ch_read(tdc, ADMA_CH_FIFO_CTRL);
738 		ch_reg->config = tdma_ch_read(tdc, ADMA_CH_CONFIG);
739 	}
740 
741 clk_disable:
742 	clk_disable_unprepare(tdma->ahub_clk);
743 
744 	return 0;
745 }
746 
747 static int tegra_adma_runtime_resume(struct device *dev)
748 {
749 	struct tegra_adma *tdma = dev_get_drvdata(dev);
750 	struct tegra_adma_chan_regs *ch_reg;
751 	struct tegra_adma_chan *tdc;
752 	int ret, i;
753 
754 	ret = clk_prepare_enable(tdma->ahub_clk);
755 	if (ret) {
756 		dev_err(dev, "ahub clk_enable failed: %d\n", ret);
757 		return ret;
758 	}
759 	tdma_write(tdma, ADMA_GLOBAL_CMD, tdma->global_cmd);
760 
761 	if (!tdma->global_cmd)
762 		return 0;
763 
764 	for (i = 0; i < tdma->nr_channels; i++) {
765 		tdc = &tdma->channels[i];
766 		ch_reg = &tdc->ch_regs;
767 		/* skip if channel was not active earlier */
768 		if (!ch_reg->cmd)
769 			continue;
770 		tdma_ch_write(tdc, ADMA_CH_TC, ch_reg->tc);
771 		tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_reg->src_addr);
772 		tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_reg->trg_addr);
773 		tdma_ch_write(tdc, ADMA_CH_CTRL, ch_reg->ctrl);
774 		tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_reg->fifo_ctrl);
775 		tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_reg->config);
776 		tdma_ch_write(tdc, ADMA_CH_CMD, ch_reg->cmd);
777 	}
778 
779 	return 0;
780 }
781 
782 static const struct tegra_adma_chip_data tegra210_chip_data = {
783 	.adma_get_burst_config  = tegra210_adma_get_burst_config,
784 	.global_reg_offset	= 0xc00,
785 	.global_int_clear	= 0x20,
786 	.ch_req_tx_shift	= 28,
787 	.ch_req_rx_shift	= 24,
788 	.ch_base_offset		= 0,
789 	.ch_fifo_ctrl		= TEGRA210_FIFO_CTRL_DEFAULT,
790 	.ch_req_mask		= 0xf,
791 	.ch_req_max		= 10,
792 	.ch_reg_size		= 0x80,
793 	.nr_channels		= 22,
794 };
795 
796 static const struct tegra_adma_chip_data tegra186_chip_data = {
797 	.adma_get_burst_config  = tegra186_adma_get_burst_config,
798 	.global_reg_offset	= 0,
799 	.global_int_clear	= 0x402c,
800 	.ch_req_tx_shift	= 27,
801 	.ch_req_rx_shift	= 22,
802 	.ch_base_offset		= 0x10000,
803 	.ch_fifo_ctrl		= TEGRA186_FIFO_CTRL_DEFAULT,
804 	.ch_req_mask		= 0x1f,
805 	.ch_req_max		= 20,
806 	.ch_reg_size		= 0x100,
807 	.nr_channels		= 32,
808 };
809 
810 static const struct of_device_id tegra_adma_of_match[] = {
811 	{ .compatible = "nvidia,tegra210-adma", .data = &tegra210_chip_data },
812 	{ .compatible = "nvidia,tegra186-adma", .data = &tegra186_chip_data },
813 	{ },
814 };
815 MODULE_DEVICE_TABLE(of, tegra_adma_of_match);
816 
817 static int tegra_adma_probe(struct platform_device *pdev)
818 {
819 	const struct tegra_adma_chip_data *cdata;
820 	struct tegra_adma *tdma;
821 	struct resource	*res;
822 	int ret, i;
823 
824 	cdata = of_device_get_match_data(&pdev->dev);
825 	if (!cdata) {
826 		dev_err(&pdev->dev, "device match data not found\n");
827 		return -ENODEV;
828 	}
829 
830 	tdma = devm_kzalloc(&pdev->dev,
831 			    struct_size(tdma, channels, cdata->nr_channels),
832 			    GFP_KERNEL);
833 	if (!tdma)
834 		return -ENOMEM;
835 
836 	tdma->dev = &pdev->dev;
837 	tdma->cdata = cdata;
838 	tdma->nr_channels = cdata->nr_channels;
839 	platform_set_drvdata(pdev, tdma);
840 
841 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
842 	tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
843 	if (IS_ERR(tdma->base_addr))
844 		return PTR_ERR(tdma->base_addr);
845 
846 	tdma->ahub_clk = devm_clk_get(&pdev->dev, "d_audio");
847 	if (IS_ERR(tdma->ahub_clk)) {
848 		dev_err(&pdev->dev, "Error: Missing ahub controller clock\n");
849 		return PTR_ERR(tdma->ahub_clk);
850 	}
851 
852 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
853 	for (i = 0; i < tdma->nr_channels; i++) {
854 		struct tegra_adma_chan *tdc = &tdma->channels[i];
855 
856 		tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
857 				 + (cdata->ch_reg_size * i);
858 
859 		tdc->irq = of_irq_get(pdev->dev.of_node, i);
860 		if (tdc->irq <= 0) {
861 			ret = tdc->irq ?: -ENXIO;
862 			goto irq_dispose;
863 		}
864 
865 		vchan_init(&tdc->vc, &tdma->dma_dev);
866 		tdc->vc.desc_free = tegra_adma_desc_free;
867 		tdc->tdma = tdma;
868 	}
869 
870 	pm_runtime_enable(&pdev->dev);
871 
872 	ret = pm_runtime_get_sync(&pdev->dev);
873 	if (ret < 0)
874 		goto rpm_disable;
875 
876 	ret = tegra_adma_init(tdma);
877 	if (ret)
878 		goto rpm_put;
879 
880 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
881 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
882 	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
883 
884 	tdma->dma_dev.dev = &pdev->dev;
885 	tdma->dma_dev.device_alloc_chan_resources =
886 					tegra_adma_alloc_chan_resources;
887 	tdma->dma_dev.device_free_chan_resources =
888 					tegra_adma_free_chan_resources;
889 	tdma->dma_dev.device_issue_pending = tegra_adma_issue_pending;
890 	tdma->dma_dev.device_prep_dma_cyclic = tegra_adma_prep_dma_cyclic;
891 	tdma->dma_dev.device_config = tegra_adma_slave_config;
892 	tdma->dma_dev.device_tx_status = tegra_adma_tx_status;
893 	tdma->dma_dev.device_terminate_all = tegra_adma_terminate_all;
894 	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
895 	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
896 	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
897 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
898 	tdma->dma_dev.device_pause = tegra_adma_pause;
899 	tdma->dma_dev.device_resume = tegra_adma_resume;
900 
901 	ret = dma_async_device_register(&tdma->dma_dev);
902 	if (ret < 0) {
903 		dev_err(&pdev->dev, "ADMA registration failed: %d\n", ret);
904 		goto irq_dispose;
905 	}
906 
907 	ret = of_dma_controller_register(pdev->dev.of_node,
908 					 tegra_dma_of_xlate, tdma);
909 	if (ret < 0) {
910 		dev_err(&pdev->dev, "ADMA OF registration failed %d\n", ret);
911 		goto dma_remove;
912 	}
913 
914 	pm_runtime_put(&pdev->dev);
915 
916 	dev_info(&pdev->dev, "Tegra210 ADMA driver registered %d channels\n",
917 		 tdma->nr_channels);
918 
919 	return 0;
920 
921 dma_remove:
922 	dma_async_device_unregister(&tdma->dma_dev);
923 rpm_put:
924 	pm_runtime_put_sync(&pdev->dev);
925 rpm_disable:
926 	pm_runtime_disable(&pdev->dev);
927 irq_dispose:
928 	while (--i >= 0)
929 		irq_dispose_mapping(tdma->channels[i].irq);
930 
931 	return ret;
932 }
933 
934 static int tegra_adma_remove(struct platform_device *pdev)
935 {
936 	struct tegra_adma *tdma = platform_get_drvdata(pdev);
937 	int i;
938 
939 	of_dma_controller_free(pdev->dev.of_node);
940 	dma_async_device_unregister(&tdma->dma_dev);
941 
942 	for (i = 0; i < tdma->nr_channels; ++i)
943 		irq_dispose_mapping(tdma->channels[i].irq);
944 
945 	pm_runtime_put_sync(&pdev->dev);
946 	pm_runtime_disable(&pdev->dev);
947 
948 	return 0;
949 }
950 
951 static const struct dev_pm_ops tegra_adma_dev_pm_ops = {
952 	SET_RUNTIME_PM_OPS(tegra_adma_runtime_suspend,
953 			   tegra_adma_runtime_resume, NULL)
954 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
955 				     pm_runtime_force_resume)
956 };
957 
958 static struct platform_driver tegra_admac_driver = {
959 	.driver = {
960 		.name	= "tegra-adma",
961 		.pm	= &tegra_adma_dev_pm_ops,
962 		.of_match_table = tegra_adma_of_match,
963 	},
964 	.probe		= tegra_adma_probe,
965 	.remove		= tegra_adma_remove,
966 };
967 
968 module_platform_driver(tegra_admac_driver);
969 
970 MODULE_ALIAS("platform:tegra210-adma");
971 MODULE_DESCRIPTION("NVIDIA Tegra ADMA driver");
972 MODULE_AUTHOR("Dara Ramesh <dramesh@nvidia.com>");
973 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
974 MODULE_LICENSE("GPL v2");
975