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.h>
12 #include <linux/of_dma.h>
13 #include <linux/of_irq.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/slab.h>
17 
18 #include "virt-dma.h"
19 
20 #define ADMA_CH_CMD					0x00
21 #define ADMA_CH_STATUS					0x0c
22 #define ADMA_CH_STATUS_XFER_EN				BIT(0)
23 #define ADMA_CH_STATUS_XFER_PAUSED			BIT(1)
24 
25 #define ADMA_CH_INT_STATUS				0x10
26 #define ADMA_CH_INT_STATUS_XFER_DONE			BIT(0)
27 
28 #define ADMA_CH_INT_CLEAR				0x1c
29 #define ADMA_CH_CTRL					0x24
30 #define ADMA_CH_CTRL_DIR(val)				(((val) & 0xf) << 12)
31 #define ADMA_CH_CTRL_DIR_AHUB2MEM			2
32 #define ADMA_CH_CTRL_DIR_MEM2AHUB			4
33 #define ADMA_CH_CTRL_MODE_CONTINUOUS			(2 << 8)
34 #define ADMA_CH_CTRL_FLOWCTRL_EN			BIT(1)
35 #define ADMA_CH_CTRL_XFER_PAUSE_SHIFT			0
36 
37 #define ADMA_CH_CONFIG					0x28
38 #define ADMA_CH_CONFIG_SRC_BUF(val)			(((val) & 0x7) << 28)
39 #define ADMA_CH_CONFIG_TRG_BUF(val)			(((val) & 0x7) << 24)
40 #define ADMA_CH_CONFIG_BURST_SIZE_SHIFT			20
41 #define ADMA_CH_CONFIG_MAX_BURST_SIZE                   16
42 #define ADMA_CH_CONFIG_WEIGHT_FOR_WRR(val)		((val) & 0xf)
43 #define ADMA_CH_CONFIG_MAX_BUFS				8
44 #define TEGRA186_ADMA_CH_CONFIG_OUTSTANDING_REQS(reqs)	(reqs << 4)
45 
46 #define ADMA_CH_FIFO_CTRL				0x2c
47 #define ADMA_CH_TX_FIFO_SIZE_SHIFT			8
48 #define ADMA_CH_RX_FIFO_SIZE_SHIFT			0
49 
50 #define ADMA_CH_LOWER_SRC_ADDR				0x34
51 #define ADMA_CH_LOWER_TRG_ADDR				0x3c
52 #define ADMA_CH_TC					0x44
53 #define ADMA_CH_TC_COUNT_MASK				0x3ffffffc
54 
55 #define ADMA_CH_XFER_STATUS				0x54
56 #define ADMA_CH_XFER_STATUS_COUNT_MASK			0xffff
57 
58 #define ADMA_GLOBAL_CMD					0x00
59 #define ADMA_GLOBAL_SOFT_RESET				0x04
60 
61 #define TEGRA_ADMA_BURST_COMPLETE_TIME			20
62 
63 #define ADMA_CH_REG_FIELD_VAL(val, mask, shift)	(((val) & mask) << shift)
64 
65 struct tegra_adma;
66 
67 /*
68  * struct tegra_adma_chip_data - Tegra chip specific data
69  * @adma_get_burst_config: Function callback used to set DMA burst size.
70  * @global_reg_offset: Register offset of DMA global register.
71  * @global_int_clear: Register offset of DMA global interrupt clear.
72  * @ch_req_tx_shift: Register offset for AHUB transmit channel select.
73  * @ch_req_rx_shift: Register offset for AHUB receive channel select.
74  * @ch_base_offset: Register offset of DMA channel registers.
75  * @ch_fifo_ctrl: Default value for channel FIFO CTRL register.
76  * @ch_req_mask: Mask for Tx or Rx channel select.
77  * @ch_req_max: Maximum number of Tx or Rx channels available.
78  * @ch_reg_size: Size of DMA channel register space.
79  * @nr_channels: Number of DMA channels available.
80  * @ch_fifo_size_mask: Mask for FIFO size field.
81  * @sreq_index_offset: Slave channel index offset.
82  * @has_outstanding_reqs: If DMA channel can have outstanding requests.
83  */
84 struct tegra_adma_chip_data {
85 	unsigned int (*adma_get_burst_config)(unsigned int burst_size);
86 	unsigned int global_reg_offset;
87 	unsigned int global_int_clear;
88 	unsigned int ch_req_tx_shift;
89 	unsigned int ch_req_rx_shift;
90 	unsigned int ch_base_offset;
91 	unsigned int ch_fifo_ctrl;
92 	unsigned int ch_req_mask;
93 	unsigned int ch_req_max;
94 	unsigned int ch_reg_size;
95 	unsigned int nr_channels;
96 	unsigned int ch_fifo_size_mask;
97 	unsigned int sreq_index_offset;
98 	bool has_outstanding_reqs;
99 };
100 
101 /*
102  * struct tegra_adma_chan_regs - Tegra ADMA channel registers
103  */
104 struct tegra_adma_chan_regs {
105 	unsigned int ctrl;
106 	unsigned int config;
107 	unsigned int src_addr;
108 	unsigned int trg_addr;
109 	unsigned int fifo_ctrl;
110 	unsigned int cmd;
111 	unsigned int tc;
112 };
113 
114 /*
115  * struct tegra_adma_desc - Tegra ADMA descriptor to manage transfer requests.
116  */
117 struct tegra_adma_desc {
118 	struct virt_dma_desc		vd;
119 	struct tegra_adma_chan_regs	ch_regs;
120 	size_t				buf_len;
121 	size_t				period_len;
122 	size_t				num_periods;
123 };
124 
125 /*
126  * struct tegra_adma_chan - Tegra ADMA channel information
127  */
128 struct tegra_adma_chan {
129 	struct virt_dma_chan		vc;
130 	struct tegra_adma_desc		*desc;
131 	struct tegra_adma		*tdma;
132 	int				irq;
133 	void __iomem			*chan_addr;
134 
135 	/* Slave channel configuration info */
136 	struct dma_slave_config		sconfig;
137 	enum dma_transfer_direction	sreq_dir;
138 	unsigned int			sreq_index;
139 	bool				sreq_reserved;
140 	struct tegra_adma_chan_regs	ch_regs;
141 
142 	/* Transfer count and position info */
143 	unsigned int			tx_buf_count;
144 	unsigned int			tx_buf_pos;
145 };
146 
147 /*
148  * struct tegra_adma - Tegra ADMA controller information
149  */
150 struct tegra_adma {
151 	struct dma_device		dma_dev;
152 	struct device			*dev;
153 	void __iomem			*base_addr;
154 	struct clk			*ahub_clk;
155 	unsigned int			nr_channels;
156 	unsigned long			rx_requests_reserved;
157 	unsigned long			tx_requests_reserved;
158 
159 	/* Used to store global command register state when suspending */
160 	unsigned int			global_cmd;
161 
162 	const struct tegra_adma_chip_data *cdata;
163 
164 	/* Last member of the structure */
165 	struct tegra_adma_chan		channels[];
166 };
167 
tdma_write(struct tegra_adma * tdma,u32 reg,u32 val)168 static inline void tdma_write(struct tegra_adma *tdma, u32 reg, u32 val)
169 {
170 	writel(val, tdma->base_addr + tdma->cdata->global_reg_offset + reg);
171 }
172 
tdma_read(struct tegra_adma * tdma,u32 reg)173 static inline u32 tdma_read(struct tegra_adma *tdma, u32 reg)
174 {
175 	return readl(tdma->base_addr + tdma->cdata->global_reg_offset + reg);
176 }
177 
tdma_ch_write(struct tegra_adma_chan * tdc,u32 reg,u32 val)178 static inline void tdma_ch_write(struct tegra_adma_chan *tdc, u32 reg, u32 val)
179 {
180 	writel(val, tdc->chan_addr + reg);
181 }
182 
tdma_ch_read(struct tegra_adma_chan * tdc,u32 reg)183 static inline u32 tdma_ch_read(struct tegra_adma_chan *tdc, u32 reg)
184 {
185 	return readl(tdc->chan_addr + reg);
186 }
187 
to_tegra_adma_chan(struct dma_chan * dc)188 static inline struct tegra_adma_chan *to_tegra_adma_chan(struct dma_chan *dc)
189 {
190 	return container_of(dc, struct tegra_adma_chan, vc.chan);
191 }
192 
to_tegra_adma_desc(struct dma_async_tx_descriptor * td)193 static inline struct tegra_adma_desc *to_tegra_adma_desc(
194 		struct dma_async_tx_descriptor *td)
195 {
196 	return container_of(td, struct tegra_adma_desc, vd.tx);
197 }
198 
tdc2dev(struct tegra_adma_chan * tdc)199 static inline struct device *tdc2dev(struct tegra_adma_chan *tdc)
200 {
201 	return tdc->tdma->dev;
202 }
203 
tegra_adma_desc_free(struct virt_dma_desc * vd)204 static void tegra_adma_desc_free(struct virt_dma_desc *vd)
205 {
206 	kfree(container_of(vd, struct tegra_adma_desc, vd));
207 }
208 
tegra_adma_slave_config(struct dma_chan * dc,struct dma_slave_config * sconfig)209 static int tegra_adma_slave_config(struct dma_chan *dc,
210 				   struct dma_slave_config *sconfig)
211 {
212 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
213 
214 	memcpy(&tdc->sconfig, sconfig, sizeof(*sconfig));
215 
216 	return 0;
217 }
218 
tegra_adma_init(struct tegra_adma * tdma)219 static int tegra_adma_init(struct tegra_adma *tdma)
220 {
221 	u32 status;
222 	int ret;
223 
224 	/* Clear any interrupts */
225 	tdma_write(tdma, tdma->cdata->ch_base_offset + tdma->cdata->global_int_clear, 0x1);
226 
227 	/* Assert soft reset */
228 	tdma_write(tdma, ADMA_GLOBAL_SOFT_RESET, 0x1);
229 
230 	/* Wait for reset to clear */
231 	ret = readx_poll_timeout(readl,
232 				 tdma->base_addr +
233 				 tdma->cdata->global_reg_offset +
234 				 ADMA_GLOBAL_SOFT_RESET,
235 				 status, status == 0, 20, 10000);
236 	if (ret)
237 		return ret;
238 
239 	/* Enable global ADMA registers */
240 	tdma_write(tdma, ADMA_GLOBAL_CMD, 1);
241 
242 	return 0;
243 }
244 
tegra_adma_request_alloc(struct tegra_adma_chan * tdc,enum dma_transfer_direction direction)245 static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
246 				    enum dma_transfer_direction direction)
247 {
248 	struct tegra_adma *tdma = tdc->tdma;
249 	unsigned int sreq_index = tdc->sreq_index;
250 
251 	if (tdc->sreq_reserved)
252 		return tdc->sreq_dir == direction ? 0 : -EINVAL;
253 
254 	if (sreq_index > tdma->cdata->ch_req_max) {
255 		dev_err(tdma->dev, "invalid DMA request\n");
256 		return -EINVAL;
257 	}
258 
259 	switch (direction) {
260 	case DMA_MEM_TO_DEV:
261 		if (test_and_set_bit(sreq_index, &tdma->tx_requests_reserved)) {
262 			dev_err(tdma->dev, "DMA request reserved\n");
263 			return -EINVAL;
264 		}
265 		break;
266 
267 	case DMA_DEV_TO_MEM:
268 		if (test_and_set_bit(sreq_index, &tdma->rx_requests_reserved)) {
269 			dev_err(tdma->dev, "DMA request reserved\n");
270 			return -EINVAL;
271 		}
272 		break;
273 
274 	default:
275 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
276 			 dma_chan_name(&tdc->vc.chan));
277 		return -EINVAL;
278 	}
279 
280 	tdc->sreq_dir = direction;
281 	tdc->sreq_reserved = true;
282 
283 	return 0;
284 }
285 
tegra_adma_request_free(struct tegra_adma_chan * tdc)286 static void tegra_adma_request_free(struct tegra_adma_chan *tdc)
287 {
288 	struct tegra_adma *tdma = tdc->tdma;
289 
290 	if (!tdc->sreq_reserved)
291 		return;
292 
293 	switch (tdc->sreq_dir) {
294 	case DMA_MEM_TO_DEV:
295 		clear_bit(tdc->sreq_index, &tdma->tx_requests_reserved);
296 		break;
297 
298 	case DMA_DEV_TO_MEM:
299 		clear_bit(tdc->sreq_index, &tdma->rx_requests_reserved);
300 		break;
301 
302 	default:
303 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
304 			 dma_chan_name(&tdc->vc.chan));
305 		return;
306 	}
307 
308 	tdc->sreq_reserved = false;
309 }
310 
tegra_adma_irq_status(struct tegra_adma_chan * tdc)311 static u32 tegra_adma_irq_status(struct tegra_adma_chan *tdc)
312 {
313 	u32 status = tdma_ch_read(tdc, ADMA_CH_INT_STATUS);
314 
315 	return status & ADMA_CH_INT_STATUS_XFER_DONE;
316 }
317 
tegra_adma_irq_clear(struct tegra_adma_chan * tdc)318 static u32 tegra_adma_irq_clear(struct tegra_adma_chan *tdc)
319 {
320 	u32 status = tegra_adma_irq_status(tdc);
321 
322 	if (status)
323 		tdma_ch_write(tdc, ADMA_CH_INT_CLEAR, status);
324 
325 	return status;
326 }
327 
tegra_adma_stop(struct tegra_adma_chan * tdc)328 static void tegra_adma_stop(struct tegra_adma_chan *tdc)
329 {
330 	unsigned int status;
331 
332 	/* Disable ADMA */
333 	tdma_ch_write(tdc, ADMA_CH_CMD, 0);
334 
335 	/* Clear interrupt status */
336 	tegra_adma_irq_clear(tdc);
337 
338 	if (readx_poll_timeout_atomic(readl, tdc->chan_addr + ADMA_CH_STATUS,
339 			status, !(status & ADMA_CH_STATUS_XFER_EN),
340 			20, 10000)) {
341 		dev_err(tdc2dev(tdc), "unable to stop DMA channel\n");
342 		return;
343 	}
344 
345 	kfree(tdc->desc);
346 	tdc->desc = NULL;
347 }
348 
tegra_adma_start(struct tegra_adma_chan * tdc)349 static void tegra_adma_start(struct tegra_adma_chan *tdc)
350 {
351 	struct virt_dma_desc *vd = vchan_next_desc(&tdc->vc);
352 	struct tegra_adma_chan_regs *ch_regs;
353 	struct tegra_adma_desc *desc;
354 
355 	if (!vd)
356 		return;
357 
358 	list_del(&vd->node);
359 
360 	desc = to_tegra_adma_desc(&vd->tx);
361 
362 	if (!desc) {
363 		dev_warn(tdc2dev(tdc), "unable to start DMA, no descriptor\n");
364 		return;
365 	}
366 
367 	ch_regs = &desc->ch_regs;
368 
369 	tdc->tx_buf_pos = 0;
370 	tdc->tx_buf_count = 0;
371 	tdma_ch_write(tdc, ADMA_CH_TC, ch_regs->tc);
372 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
373 	tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_regs->src_addr);
374 	tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_regs->trg_addr);
375 	tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_regs->fifo_ctrl);
376 	tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_regs->config);
377 
378 	/* Start ADMA */
379 	tdma_ch_write(tdc, ADMA_CH_CMD, 1);
380 
381 	tdc->desc = desc;
382 }
383 
tegra_adma_get_residue(struct tegra_adma_chan * tdc)384 static unsigned int tegra_adma_get_residue(struct tegra_adma_chan *tdc)
385 {
386 	struct tegra_adma_desc *desc = tdc->desc;
387 	unsigned int max = ADMA_CH_XFER_STATUS_COUNT_MASK + 1;
388 	unsigned int pos = tdma_ch_read(tdc, ADMA_CH_XFER_STATUS);
389 	unsigned int periods_remaining;
390 
391 	/*
392 	 * Handle wrap around of buffer count register
393 	 */
394 	if (pos < tdc->tx_buf_pos)
395 		tdc->tx_buf_count += pos + (max - tdc->tx_buf_pos);
396 	else
397 		tdc->tx_buf_count += pos - tdc->tx_buf_pos;
398 
399 	periods_remaining = tdc->tx_buf_count % desc->num_periods;
400 	tdc->tx_buf_pos = pos;
401 
402 	return desc->buf_len - (periods_remaining * desc->period_len);
403 }
404 
tegra_adma_isr(int irq,void * dev_id)405 static irqreturn_t tegra_adma_isr(int irq, void *dev_id)
406 {
407 	struct tegra_adma_chan *tdc = dev_id;
408 	unsigned long status;
409 
410 	spin_lock(&tdc->vc.lock);
411 
412 	status = tegra_adma_irq_clear(tdc);
413 	if (status == 0 || !tdc->desc) {
414 		spin_unlock(&tdc->vc.lock);
415 		return IRQ_NONE;
416 	}
417 
418 	vchan_cyclic_callback(&tdc->desc->vd);
419 
420 	spin_unlock(&tdc->vc.lock);
421 
422 	return IRQ_HANDLED;
423 }
424 
tegra_adma_issue_pending(struct dma_chan * dc)425 static void tegra_adma_issue_pending(struct dma_chan *dc)
426 {
427 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
428 	unsigned long flags;
429 
430 	spin_lock_irqsave(&tdc->vc.lock, flags);
431 
432 	if (vchan_issue_pending(&tdc->vc)) {
433 		if (!tdc->desc)
434 			tegra_adma_start(tdc);
435 	}
436 
437 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
438 }
439 
tegra_adma_is_paused(struct tegra_adma_chan * tdc)440 static bool tegra_adma_is_paused(struct tegra_adma_chan *tdc)
441 {
442 	u32 csts;
443 
444 	csts = tdma_ch_read(tdc, ADMA_CH_STATUS);
445 	csts &= ADMA_CH_STATUS_XFER_PAUSED;
446 
447 	return csts ? true : false;
448 }
449 
tegra_adma_pause(struct dma_chan * dc)450 static int tegra_adma_pause(struct dma_chan *dc)
451 {
452 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
453 	struct tegra_adma_desc *desc = tdc->desc;
454 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
455 	int dcnt = 10;
456 
457 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
458 	ch_regs->ctrl |= (1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
459 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
460 
461 	while (dcnt-- && !tegra_adma_is_paused(tdc))
462 		udelay(TEGRA_ADMA_BURST_COMPLETE_TIME);
463 
464 	if (dcnt < 0) {
465 		dev_err(tdc2dev(tdc), "unable to pause DMA channel\n");
466 		return -EBUSY;
467 	}
468 
469 	return 0;
470 }
471 
tegra_adma_resume(struct dma_chan * dc)472 static int tegra_adma_resume(struct dma_chan *dc)
473 {
474 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
475 	struct tegra_adma_desc *desc = tdc->desc;
476 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
477 
478 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
479 	ch_regs->ctrl &= ~(1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
480 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
481 
482 	return 0;
483 }
484 
tegra_adma_terminate_all(struct dma_chan * dc)485 static int tegra_adma_terminate_all(struct dma_chan *dc)
486 {
487 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
488 	unsigned long flags;
489 	LIST_HEAD(head);
490 
491 	spin_lock_irqsave(&tdc->vc.lock, flags);
492 
493 	if (tdc->desc)
494 		tegra_adma_stop(tdc);
495 
496 	tegra_adma_request_free(tdc);
497 	vchan_get_all_descriptors(&tdc->vc, &head);
498 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
499 	vchan_dma_desc_free_list(&tdc->vc, &head);
500 
501 	return 0;
502 }
503 
tegra_adma_tx_status(struct dma_chan * dc,dma_cookie_t cookie,struct dma_tx_state * txstate)504 static enum dma_status tegra_adma_tx_status(struct dma_chan *dc,
505 					    dma_cookie_t cookie,
506 					    struct dma_tx_state *txstate)
507 {
508 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
509 	struct tegra_adma_desc *desc;
510 	struct virt_dma_desc *vd;
511 	enum dma_status ret;
512 	unsigned long flags;
513 	unsigned int residual;
514 
515 	ret = dma_cookie_status(dc, cookie, txstate);
516 	if (ret == DMA_COMPLETE || !txstate)
517 		return ret;
518 
519 	spin_lock_irqsave(&tdc->vc.lock, flags);
520 
521 	vd = vchan_find_desc(&tdc->vc, cookie);
522 	if (vd) {
523 		desc = to_tegra_adma_desc(&vd->tx);
524 		residual = desc->ch_regs.tc;
525 	} else if (tdc->desc && tdc->desc->vd.tx.cookie == cookie) {
526 		residual = tegra_adma_get_residue(tdc);
527 	} else {
528 		residual = 0;
529 	}
530 
531 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
532 
533 	dma_set_residue(txstate, residual);
534 
535 	return ret;
536 }
537 
tegra210_adma_get_burst_config(unsigned int burst_size)538 static unsigned int tegra210_adma_get_burst_config(unsigned int burst_size)
539 {
540 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
541 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
542 
543 	return fls(burst_size) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
544 }
545 
tegra186_adma_get_burst_config(unsigned int burst_size)546 static unsigned int tegra186_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 (burst_size - 1) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
552 }
553 
tegra_adma_set_xfer_params(struct tegra_adma_chan * tdc,struct tegra_adma_desc * desc,dma_addr_t buf_addr,enum dma_transfer_direction direction)554 static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
555 				      struct tegra_adma_desc *desc,
556 				      dma_addr_t buf_addr,
557 				      enum dma_transfer_direction direction)
558 {
559 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
560 	const struct tegra_adma_chip_data *cdata = tdc->tdma->cdata;
561 	unsigned int burst_size, adma_dir, fifo_size_shift;
562 
563 	if (desc->num_periods > ADMA_CH_CONFIG_MAX_BUFS)
564 		return -EINVAL;
565 
566 	switch (direction) {
567 	case DMA_MEM_TO_DEV:
568 		fifo_size_shift = ADMA_CH_TX_FIFO_SIZE_SHIFT;
569 		adma_dir = ADMA_CH_CTRL_DIR_MEM2AHUB;
570 		burst_size = tdc->sconfig.dst_maxburst;
571 		ch_regs->config = ADMA_CH_CONFIG_SRC_BUF(desc->num_periods - 1);
572 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
573 						      cdata->ch_req_mask,
574 						      cdata->ch_req_tx_shift);
575 		ch_regs->src_addr = buf_addr;
576 		break;
577 
578 	case DMA_DEV_TO_MEM:
579 		fifo_size_shift = ADMA_CH_RX_FIFO_SIZE_SHIFT;
580 		adma_dir = ADMA_CH_CTRL_DIR_AHUB2MEM;
581 		burst_size = tdc->sconfig.src_maxburst;
582 		ch_regs->config = ADMA_CH_CONFIG_TRG_BUF(desc->num_periods - 1);
583 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
584 						      cdata->ch_req_mask,
585 						      cdata->ch_req_rx_shift);
586 		ch_regs->trg_addr = buf_addr;
587 		break;
588 
589 	default:
590 		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
591 		return -EINVAL;
592 	}
593 
594 	ch_regs->ctrl |= ADMA_CH_CTRL_DIR(adma_dir) |
595 			 ADMA_CH_CTRL_MODE_CONTINUOUS |
596 			 ADMA_CH_CTRL_FLOWCTRL_EN;
597 	ch_regs->config |= cdata->adma_get_burst_config(burst_size);
598 	ch_regs->config |= ADMA_CH_CONFIG_WEIGHT_FOR_WRR(1);
599 	if (cdata->has_outstanding_reqs)
600 		ch_regs->config |= TEGRA186_ADMA_CH_CONFIG_OUTSTANDING_REQS(8);
601 
602 	/*
603 	 * 'sreq_index' represents the current ADMAIF channel number and as per
604 	 * HW recommendation its FIFO size should match with the corresponding
605 	 * ADMA channel.
606 	 *
607 	 * ADMA FIFO size is set as per below (based on default ADMAIF channel
608 	 * FIFO sizes):
609 	 *    fifo_size = 0x2 (sreq_index > sreq_index_offset)
610 	 *    fifo_size = 0x3 (sreq_index <= sreq_index_offset)
611 	 *
612 	 */
613 	if (tdc->sreq_index > cdata->sreq_index_offset)
614 		ch_regs->fifo_ctrl =
615 			ADMA_CH_REG_FIELD_VAL(2, cdata->ch_fifo_size_mask,
616 					      fifo_size_shift);
617 	else
618 		ch_regs->fifo_ctrl =
619 			ADMA_CH_REG_FIELD_VAL(3, cdata->ch_fifo_size_mask,
620 					      fifo_size_shift);
621 
622 	ch_regs->tc = desc->period_len & ADMA_CH_TC_COUNT_MASK;
623 
624 	return tegra_adma_request_alloc(tdc, direction);
625 }
626 
tegra_adma_prep_dma_cyclic(struct dma_chan * dc,dma_addr_t buf_addr,size_t buf_len,size_t period_len,enum dma_transfer_direction direction,unsigned long flags)627 static struct dma_async_tx_descriptor *tegra_adma_prep_dma_cyclic(
628 	struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
629 	size_t period_len, enum dma_transfer_direction direction,
630 	unsigned long flags)
631 {
632 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
633 	struct tegra_adma_desc *desc = NULL;
634 
635 	if (!buf_len || !period_len || period_len > ADMA_CH_TC_COUNT_MASK) {
636 		dev_err(tdc2dev(tdc), "invalid buffer/period len\n");
637 		return NULL;
638 	}
639 
640 	if (buf_len % period_len) {
641 		dev_err(tdc2dev(tdc), "buf_len not a multiple of period_len\n");
642 		return NULL;
643 	}
644 
645 	if (!IS_ALIGNED(buf_addr, 4)) {
646 		dev_err(tdc2dev(tdc), "invalid buffer alignment\n");
647 		return NULL;
648 	}
649 
650 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
651 	if (!desc)
652 		return NULL;
653 
654 	desc->buf_len = buf_len;
655 	desc->period_len = period_len;
656 	desc->num_periods = buf_len / period_len;
657 
658 	if (tegra_adma_set_xfer_params(tdc, desc, buf_addr, direction)) {
659 		kfree(desc);
660 		return NULL;
661 	}
662 
663 	return vchan_tx_prep(&tdc->vc, &desc->vd, flags);
664 }
665 
tegra_adma_alloc_chan_resources(struct dma_chan * dc)666 static int tegra_adma_alloc_chan_resources(struct dma_chan *dc)
667 {
668 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
669 	int ret;
670 
671 	ret = request_irq(tdc->irq, tegra_adma_isr, 0, dma_chan_name(dc), tdc);
672 	if (ret) {
673 		dev_err(tdc2dev(tdc), "failed to get interrupt for %s\n",
674 			dma_chan_name(dc));
675 		return ret;
676 	}
677 
678 	ret = pm_runtime_resume_and_get(tdc2dev(tdc));
679 	if (ret < 0) {
680 		free_irq(tdc->irq, tdc);
681 		return ret;
682 	}
683 
684 	dma_cookie_init(&tdc->vc.chan);
685 
686 	return 0;
687 }
688 
tegra_adma_free_chan_resources(struct dma_chan * dc)689 static void tegra_adma_free_chan_resources(struct dma_chan *dc)
690 {
691 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
692 
693 	tegra_adma_terminate_all(dc);
694 	vchan_free_chan_resources(&tdc->vc);
695 	tasklet_kill(&tdc->vc.task);
696 	free_irq(tdc->irq, tdc);
697 	pm_runtime_put(tdc2dev(tdc));
698 
699 	tdc->sreq_index = 0;
700 	tdc->sreq_dir = DMA_TRANS_NONE;
701 }
702 
tegra_dma_of_xlate(struct of_phandle_args * dma_spec,struct of_dma * ofdma)703 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
704 					   struct of_dma *ofdma)
705 {
706 	struct tegra_adma *tdma = ofdma->of_dma_data;
707 	struct tegra_adma_chan *tdc;
708 	struct dma_chan *chan;
709 	unsigned int sreq_index;
710 
711 	if (dma_spec->args_count != 1)
712 		return NULL;
713 
714 	sreq_index = dma_spec->args[0];
715 
716 	if (sreq_index == 0) {
717 		dev_err(tdma->dev, "DMA request must not be 0\n");
718 		return NULL;
719 	}
720 
721 	chan = dma_get_any_slave_channel(&tdma->dma_dev);
722 	if (!chan)
723 		return NULL;
724 
725 	tdc = to_tegra_adma_chan(chan);
726 	tdc->sreq_index = sreq_index;
727 
728 	return chan;
729 }
730 
tegra_adma_runtime_suspend(struct device * dev)731 static int __maybe_unused tegra_adma_runtime_suspend(struct device *dev)
732 {
733 	struct tegra_adma *tdma = dev_get_drvdata(dev);
734 	struct tegra_adma_chan_regs *ch_reg;
735 	struct tegra_adma_chan *tdc;
736 	int i;
737 
738 	tdma->global_cmd = tdma_read(tdma, ADMA_GLOBAL_CMD);
739 	if (!tdma->global_cmd)
740 		goto clk_disable;
741 
742 	for (i = 0; i < tdma->nr_channels; i++) {
743 		tdc = &tdma->channels[i];
744 		ch_reg = &tdc->ch_regs;
745 		ch_reg->cmd = tdma_ch_read(tdc, ADMA_CH_CMD);
746 		/* skip if channel is not active */
747 		if (!ch_reg->cmd)
748 			continue;
749 		ch_reg->tc = tdma_ch_read(tdc, ADMA_CH_TC);
750 		ch_reg->src_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_SRC_ADDR);
751 		ch_reg->trg_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_TRG_ADDR);
752 		ch_reg->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
753 		ch_reg->fifo_ctrl = tdma_ch_read(tdc, ADMA_CH_FIFO_CTRL);
754 		ch_reg->config = tdma_ch_read(tdc, ADMA_CH_CONFIG);
755 	}
756 
757 clk_disable:
758 	clk_disable_unprepare(tdma->ahub_clk);
759 
760 	return 0;
761 }
762 
tegra_adma_runtime_resume(struct device * dev)763 static int __maybe_unused tegra_adma_runtime_resume(struct device *dev)
764 {
765 	struct tegra_adma *tdma = dev_get_drvdata(dev);
766 	struct tegra_adma_chan_regs *ch_reg;
767 	struct tegra_adma_chan *tdc;
768 	int ret, i;
769 
770 	ret = clk_prepare_enable(tdma->ahub_clk);
771 	if (ret) {
772 		dev_err(dev, "ahub clk_enable failed: %d\n", ret);
773 		return ret;
774 	}
775 	tdma_write(tdma, ADMA_GLOBAL_CMD, tdma->global_cmd);
776 
777 	if (!tdma->global_cmd)
778 		return 0;
779 
780 	for (i = 0; i < tdma->nr_channels; i++) {
781 		tdc = &tdma->channels[i];
782 		ch_reg = &tdc->ch_regs;
783 		/* skip if channel was not active earlier */
784 		if (!ch_reg->cmd)
785 			continue;
786 		tdma_ch_write(tdc, ADMA_CH_TC, ch_reg->tc);
787 		tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_reg->src_addr);
788 		tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_reg->trg_addr);
789 		tdma_ch_write(tdc, ADMA_CH_CTRL, ch_reg->ctrl);
790 		tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_reg->fifo_ctrl);
791 		tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_reg->config);
792 		tdma_ch_write(tdc, ADMA_CH_CMD, ch_reg->cmd);
793 	}
794 
795 	return 0;
796 }
797 
798 static const struct tegra_adma_chip_data tegra210_chip_data = {
799 	.adma_get_burst_config  = tegra210_adma_get_burst_config,
800 	.global_reg_offset	= 0xc00,
801 	.global_int_clear	= 0x20,
802 	.ch_req_tx_shift	= 28,
803 	.ch_req_rx_shift	= 24,
804 	.ch_base_offset		= 0,
805 	.ch_req_mask		= 0xf,
806 	.ch_req_max		= 10,
807 	.ch_reg_size		= 0x80,
808 	.nr_channels		= 22,
809 	.ch_fifo_size_mask	= 0xf,
810 	.sreq_index_offset	= 2,
811 	.has_outstanding_reqs	= false,
812 };
813 
814 static const struct tegra_adma_chip_data tegra186_chip_data = {
815 	.adma_get_burst_config  = tegra186_adma_get_burst_config,
816 	.global_reg_offset	= 0,
817 	.global_int_clear	= 0x402c,
818 	.ch_req_tx_shift	= 27,
819 	.ch_req_rx_shift	= 22,
820 	.ch_base_offset		= 0x10000,
821 	.ch_req_mask		= 0x1f,
822 	.ch_req_max		= 20,
823 	.ch_reg_size		= 0x100,
824 	.nr_channels		= 32,
825 	.ch_fifo_size_mask	= 0x1f,
826 	.sreq_index_offset	= 4,
827 	.has_outstanding_reqs	= true,
828 };
829 
830 static const struct of_device_id tegra_adma_of_match[] = {
831 	{ .compatible = "nvidia,tegra210-adma", .data = &tegra210_chip_data },
832 	{ .compatible = "nvidia,tegra186-adma", .data = &tegra186_chip_data },
833 	{ },
834 };
835 MODULE_DEVICE_TABLE(of, tegra_adma_of_match);
836 
tegra_adma_probe(struct platform_device * pdev)837 static int tegra_adma_probe(struct platform_device *pdev)
838 {
839 	const struct tegra_adma_chip_data *cdata;
840 	struct tegra_adma *tdma;
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 	tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
861 	if (IS_ERR(tdma->base_addr))
862 		return PTR_ERR(tdma->base_addr);
863 
864 	tdma->ahub_clk = devm_clk_get(&pdev->dev, "d_audio");
865 	if (IS_ERR(tdma->ahub_clk)) {
866 		dev_err(&pdev->dev, "Error: Missing ahub controller clock\n");
867 		return PTR_ERR(tdma->ahub_clk);
868 	}
869 
870 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
871 	for (i = 0; i < tdma->nr_channels; i++) {
872 		struct tegra_adma_chan *tdc = &tdma->channels[i];
873 
874 		tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
875 				 + (cdata->ch_reg_size * i);
876 
877 		tdc->irq = of_irq_get(pdev->dev.of_node, i);
878 		if (tdc->irq <= 0) {
879 			ret = tdc->irq ?: -ENXIO;
880 			goto irq_dispose;
881 		}
882 
883 		vchan_init(&tdc->vc, &tdma->dma_dev);
884 		tdc->vc.desc_free = tegra_adma_desc_free;
885 		tdc->tdma = tdma;
886 	}
887 
888 	pm_runtime_enable(&pdev->dev);
889 
890 	ret = pm_runtime_resume_and_get(&pdev->dev);
891 	if (ret < 0)
892 		goto rpm_disable;
893 
894 	ret = tegra_adma_init(tdma);
895 	if (ret)
896 		goto rpm_put;
897 
898 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
899 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
900 	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
901 
902 	tdma->dma_dev.dev = &pdev->dev;
903 	tdma->dma_dev.device_alloc_chan_resources =
904 					tegra_adma_alloc_chan_resources;
905 	tdma->dma_dev.device_free_chan_resources =
906 					tegra_adma_free_chan_resources;
907 	tdma->dma_dev.device_issue_pending = tegra_adma_issue_pending;
908 	tdma->dma_dev.device_prep_dma_cyclic = tegra_adma_prep_dma_cyclic;
909 	tdma->dma_dev.device_config = tegra_adma_slave_config;
910 	tdma->dma_dev.device_tx_status = tegra_adma_tx_status;
911 	tdma->dma_dev.device_terminate_all = tegra_adma_terminate_all;
912 	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
913 	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
914 	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
915 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
916 	tdma->dma_dev.device_pause = tegra_adma_pause;
917 	tdma->dma_dev.device_resume = tegra_adma_resume;
918 
919 	ret = dma_async_device_register(&tdma->dma_dev);
920 	if (ret < 0) {
921 		dev_err(&pdev->dev, "ADMA registration failed: %d\n", ret);
922 		goto rpm_put;
923 	}
924 
925 	ret = of_dma_controller_register(pdev->dev.of_node,
926 					 tegra_dma_of_xlate, tdma);
927 	if (ret < 0) {
928 		dev_err(&pdev->dev, "ADMA OF registration failed %d\n", ret);
929 		goto dma_remove;
930 	}
931 
932 	pm_runtime_put(&pdev->dev);
933 
934 	dev_info(&pdev->dev, "Tegra210 ADMA driver registered %d channels\n",
935 		 tdma->nr_channels);
936 
937 	return 0;
938 
939 dma_remove:
940 	dma_async_device_unregister(&tdma->dma_dev);
941 rpm_put:
942 	pm_runtime_put_sync(&pdev->dev);
943 rpm_disable:
944 	pm_runtime_disable(&pdev->dev);
945 irq_dispose:
946 	while (--i >= 0)
947 		irq_dispose_mapping(tdma->channels[i].irq);
948 
949 	return ret;
950 }
951 
tegra_adma_remove(struct platform_device * pdev)952 static int tegra_adma_remove(struct platform_device *pdev)
953 {
954 	struct tegra_adma *tdma = platform_get_drvdata(pdev);
955 	int i;
956 
957 	of_dma_controller_free(pdev->dev.of_node);
958 	dma_async_device_unregister(&tdma->dma_dev);
959 
960 	for (i = 0; i < tdma->nr_channels; ++i)
961 		irq_dispose_mapping(tdma->channels[i].irq);
962 
963 	pm_runtime_disable(&pdev->dev);
964 
965 	return 0;
966 }
967 
968 static const struct dev_pm_ops tegra_adma_dev_pm_ops = {
969 	SET_RUNTIME_PM_OPS(tegra_adma_runtime_suspend,
970 			   tegra_adma_runtime_resume, NULL)
971 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
972 				     pm_runtime_force_resume)
973 };
974 
975 static struct platform_driver tegra_admac_driver = {
976 	.driver = {
977 		.name	= "tegra-adma",
978 		.pm	= &tegra_adma_dev_pm_ops,
979 		.of_match_table = tegra_adma_of_match,
980 	},
981 	.probe		= tegra_adma_probe,
982 	.remove		= tegra_adma_remove,
983 };
984 
985 module_platform_driver(tegra_admac_driver);
986 
987 MODULE_ALIAS("platform:tegra210-adma");
988 MODULE_DESCRIPTION("NVIDIA Tegra ADMA driver");
989 MODULE_AUTHOR("Dara Ramesh <dramesh@nvidia.com>");
990 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
991 MODULE_LICENSE("GPL v2");
992