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			*dma_chan_mask;
157 	unsigned long			rx_requests_reserved;
158 	unsigned long			tx_requests_reserved;
159 
160 	/* Used to store global command register state when suspending */
161 	unsigned int			global_cmd;
162 
163 	const struct tegra_adma_chip_data *cdata;
164 
165 	/* Last member of the structure */
166 	struct tegra_adma_chan		channels[] __counted_by(nr_channels);
167 };
168 
tdma_write(struct tegra_adma * tdma,u32 reg,u32 val)169 static inline void tdma_write(struct tegra_adma *tdma, u32 reg, u32 val)
170 {
171 	writel(val, tdma->base_addr + tdma->cdata->global_reg_offset + reg);
172 }
173 
tdma_read(struct tegra_adma * tdma,u32 reg)174 static inline u32 tdma_read(struct tegra_adma *tdma, u32 reg)
175 {
176 	return readl(tdma->base_addr + tdma->cdata->global_reg_offset + reg);
177 }
178 
tdma_ch_write(struct tegra_adma_chan * tdc,u32 reg,u32 val)179 static inline void tdma_ch_write(struct tegra_adma_chan *tdc, u32 reg, u32 val)
180 {
181 	writel(val, tdc->chan_addr + reg);
182 }
183 
tdma_ch_read(struct tegra_adma_chan * tdc,u32 reg)184 static inline u32 tdma_ch_read(struct tegra_adma_chan *tdc, u32 reg)
185 {
186 	return readl(tdc->chan_addr + reg);
187 }
188 
to_tegra_adma_chan(struct dma_chan * dc)189 static inline struct tegra_adma_chan *to_tegra_adma_chan(struct dma_chan *dc)
190 {
191 	return container_of(dc, struct tegra_adma_chan, vc.chan);
192 }
193 
to_tegra_adma_desc(struct dma_async_tx_descriptor * td)194 static inline struct tegra_adma_desc *to_tegra_adma_desc(
195 		struct dma_async_tx_descriptor *td)
196 {
197 	return container_of(td, struct tegra_adma_desc, vd.tx);
198 }
199 
tdc2dev(struct tegra_adma_chan * tdc)200 static inline struct device *tdc2dev(struct tegra_adma_chan *tdc)
201 {
202 	return tdc->tdma->dev;
203 }
204 
tegra_adma_desc_free(struct virt_dma_desc * vd)205 static void tegra_adma_desc_free(struct virt_dma_desc *vd)
206 {
207 	kfree(container_of(vd, struct tegra_adma_desc, vd));
208 }
209 
tegra_adma_slave_config(struct dma_chan * dc,struct dma_slave_config * sconfig)210 static int tegra_adma_slave_config(struct dma_chan *dc,
211 				   struct dma_slave_config *sconfig)
212 {
213 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
214 
215 	memcpy(&tdc->sconfig, sconfig, sizeof(*sconfig));
216 
217 	return 0;
218 }
219 
tegra_adma_init(struct tegra_adma * tdma)220 static int tegra_adma_init(struct tegra_adma *tdma)
221 {
222 	u32 status;
223 	int ret;
224 
225 	/* Clear any interrupts */
226 	tdma_write(tdma, tdma->cdata->ch_base_offset + tdma->cdata->global_int_clear, 0x1);
227 
228 	/* Assert soft reset */
229 	tdma_write(tdma, ADMA_GLOBAL_SOFT_RESET, 0x1);
230 
231 	/* Wait for reset to clear */
232 	ret = readx_poll_timeout(readl,
233 				 tdma->base_addr +
234 				 tdma->cdata->global_reg_offset +
235 				 ADMA_GLOBAL_SOFT_RESET,
236 				 status, status == 0, 20, 10000);
237 	if (ret)
238 		return ret;
239 
240 	/* Enable global ADMA registers */
241 	tdma_write(tdma, ADMA_GLOBAL_CMD, 1);
242 
243 	return 0;
244 }
245 
tegra_adma_request_alloc(struct tegra_adma_chan * tdc,enum dma_transfer_direction direction)246 static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
247 				    enum dma_transfer_direction direction)
248 {
249 	struct tegra_adma *tdma = tdc->tdma;
250 	unsigned int sreq_index = tdc->sreq_index;
251 
252 	if (tdc->sreq_reserved)
253 		return tdc->sreq_dir == direction ? 0 : -EINVAL;
254 
255 	if (sreq_index > tdma->cdata->ch_req_max) {
256 		dev_err(tdma->dev, "invalid DMA request\n");
257 		return -EINVAL;
258 	}
259 
260 	switch (direction) {
261 	case DMA_MEM_TO_DEV:
262 		if (test_and_set_bit(sreq_index, &tdma->tx_requests_reserved)) {
263 			dev_err(tdma->dev, "DMA request reserved\n");
264 			return -EINVAL;
265 		}
266 		break;
267 
268 	case DMA_DEV_TO_MEM:
269 		if (test_and_set_bit(sreq_index, &tdma->rx_requests_reserved)) {
270 			dev_err(tdma->dev, "DMA request reserved\n");
271 			return -EINVAL;
272 		}
273 		break;
274 
275 	default:
276 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
277 			 dma_chan_name(&tdc->vc.chan));
278 		return -EINVAL;
279 	}
280 
281 	tdc->sreq_dir = direction;
282 	tdc->sreq_reserved = true;
283 
284 	return 0;
285 }
286 
tegra_adma_request_free(struct tegra_adma_chan * tdc)287 static void tegra_adma_request_free(struct tegra_adma_chan *tdc)
288 {
289 	struct tegra_adma *tdma = tdc->tdma;
290 
291 	if (!tdc->sreq_reserved)
292 		return;
293 
294 	switch (tdc->sreq_dir) {
295 	case DMA_MEM_TO_DEV:
296 		clear_bit(tdc->sreq_index, &tdma->tx_requests_reserved);
297 		break;
298 
299 	case DMA_DEV_TO_MEM:
300 		clear_bit(tdc->sreq_index, &tdma->rx_requests_reserved);
301 		break;
302 
303 	default:
304 		dev_WARN(tdma->dev, "channel %s has invalid transfer type\n",
305 			 dma_chan_name(&tdc->vc.chan));
306 		return;
307 	}
308 
309 	tdc->sreq_reserved = false;
310 }
311 
tegra_adma_irq_status(struct tegra_adma_chan * tdc)312 static u32 tegra_adma_irq_status(struct tegra_adma_chan *tdc)
313 {
314 	u32 status = tdma_ch_read(tdc, ADMA_CH_INT_STATUS);
315 
316 	return status & ADMA_CH_INT_STATUS_XFER_DONE;
317 }
318 
tegra_adma_irq_clear(struct tegra_adma_chan * tdc)319 static u32 tegra_adma_irq_clear(struct tegra_adma_chan *tdc)
320 {
321 	u32 status = tegra_adma_irq_status(tdc);
322 
323 	if (status)
324 		tdma_ch_write(tdc, ADMA_CH_INT_CLEAR, status);
325 
326 	return status;
327 }
328 
tegra_adma_stop(struct tegra_adma_chan * tdc)329 static void tegra_adma_stop(struct tegra_adma_chan *tdc)
330 {
331 	unsigned int status;
332 
333 	/* Disable ADMA */
334 	tdma_ch_write(tdc, ADMA_CH_CMD, 0);
335 
336 	/* Clear interrupt status */
337 	tegra_adma_irq_clear(tdc);
338 
339 	if (readx_poll_timeout_atomic(readl, tdc->chan_addr + ADMA_CH_STATUS,
340 			status, !(status & ADMA_CH_STATUS_XFER_EN),
341 			20, 10000)) {
342 		dev_err(tdc2dev(tdc), "unable to stop DMA channel\n");
343 		return;
344 	}
345 
346 	kfree(tdc->desc);
347 	tdc->desc = NULL;
348 }
349 
tegra_adma_start(struct tegra_adma_chan * tdc)350 static void tegra_adma_start(struct tegra_adma_chan *tdc)
351 {
352 	struct virt_dma_desc *vd = vchan_next_desc(&tdc->vc);
353 	struct tegra_adma_chan_regs *ch_regs;
354 	struct tegra_adma_desc *desc;
355 
356 	if (!vd)
357 		return;
358 
359 	list_del(&vd->node);
360 
361 	desc = to_tegra_adma_desc(&vd->tx);
362 
363 	if (!desc) {
364 		dev_warn(tdc2dev(tdc), "unable to start DMA, no descriptor\n");
365 		return;
366 	}
367 
368 	ch_regs = &desc->ch_regs;
369 
370 	tdc->tx_buf_pos = 0;
371 	tdc->tx_buf_count = 0;
372 	tdma_ch_write(tdc, ADMA_CH_TC, ch_regs->tc);
373 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
374 	tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_regs->src_addr);
375 	tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_regs->trg_addr);
376 	tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_regs->fifo_ctrl);
377 	tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_regs->config);
378 
379 	/* Start ADMA */
380 	tdma_ch_write(tdc, ADMA_CH_CMD, 1);
381 
382 	tdc->desc = desc;
383 }
384 
tegra_adma_get_residue(struct tegra_adma_chan * tdc)385 static unsigned int tegra_adma_get_residue(struct tegra_adma_chan *tdc)
386 {
387 	struct tegra_adma_desc *desc = tdc->desc;
388 	unsigned int max = ADMA_CH_XFER_STATUS_COUNT_MASK + 1;
389 	unsigned int pos = tdma_ch_read(tdc, ADMA_CH_XFER_STATUS);
390 	unsigned int periods_remaining;
391 
392 	/*
393 	 * Handle wrap around of buffer count register
394 	 */
395 	if (pos < tdc->tx_buf_pos)
396 		tdc->tx_buf_count += pos + (max - tdc->tx_buf_pos);
397 	else
398 		tdc->tx_buf_count += pos - tdc->tx_buf_pos;
399 
400 	periods_remaining = tdc->tx_buf_count % desc->num_periods;
401 	tdc->tx_buf_pos = pos;
402 
403 	return desc->buf_len - (periods_remaining * desc->period_len);
404 }
405 
tegra_adma_isr(int irq,void * dev_id)406 static irqreturn_t tegra_adma_isr(int irq, void *dev_id)
407 {
408 	struct tegra_adma_chan *tdc = dev_id;
409 	unsigned long status;
410 
411 	spin_lock(&tdc->vc.lock);
412 
413 	status = tegra_adma_irq_clear(tdc);
414 	if (status == 0 || !tdc->desc) {
415 		spin_unlock(&tdc->vc.lock);
416 		return IRQ_NONE;
417 	}
418 
419 	vchan_cyclic_callback(&tdc->desc->vd);
420 
421 	spin_unlock(&tdc->vc.lock);
422 
423 	return IRQ_HANDLED;
424 }
425 
tegra_adma_issue_pending(struct dma_chan * dc)426 static void tegra_adma_issue_pending(struct dma_chan *dc)
427 {
428 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
429 	unsigned long flags;
430 
431 	spin_lock_irqsave(&tdc->vc.lock, flags);
432 
433 	if (vchan_issue_pending(&tdc->vc)) {
434 		if (!tdc->desc)
435 			tegra_adma_start(tdc);
436 	}
437 
438 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
439 }
440 
tegra_adma_is_paused(struct tegra_adma_chan * tdc)441 static bool tegra_adma_is_paused(struct tegra_adma_chan *tdc)
442 {
443 	u32 csts;
444 
445 	csts = tdma_ch_read(tdc, ADMA_CH_STATUS);
446 	csts &= ADMA_CH_STATUS_XFER_PAUSED;
447 
448 	return csts ? true : false;
449 }
450 
tegra_adma_pause(struct dma_chan * dc)451 static int tegra_adma_pause(struct dma_chan *dc)
452 {
453 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
454 	struct tegra_adma_desc *desc = tdc->desc;
455 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
456 	int dcnt = 10;
457 
458 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
459 	ch_regs->ctrl |= (1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
460 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
461 
462 	while (dcnt-- && !tegra_adma_is_paused(tdc))
463 		udelay(TEGRA_ADMA_BURST_COMPLETE_TIME);
464 
465 	if (dcnt < 0) {
466 		dev_err(tdc2dev(tdc), "unable to pause DMA channel\n");
467 		return -EBUSY;
468 	}
469 
470 	return 0;
471 }
472 
tegra_adma_resume(struct dma_chan * dc)473 static int tegra_adma_resume(struct dma_chan *dc)
474 {
475 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
476 	struct tegra_adma_desc *desc = tdc->desc;
477 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
478 
479 	ch_regs->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
480 	ch_regs->ctrl &= ~(1 << ADMA_CH_CTRL_XFER_PAUSE_SHIFT);
481 	tdma_ch_write(tdc, ADMA_CH_CTRL, ch_regs->ctrl);
482 
483 	return 0;
484 }
485 
tegra_adma_terminate_all(struct dma_chan * dc)486 static int tegra_adma_terminate_all(struct dma_chan *dc)
487 {
488 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
489 	unsigned long flags;
490 	LIST_HEAD(head);
491 
492 	spin_lock_irqsave(&tdc->vc.lock, flags);
493 
494 	if (tdc->desc)
495 		tegra_adma_stop(tdc);
496 
497 	tegra_adma_request_free(tdc);
498 	vchan_get_all_descriptors(&tdc->vc, &head);
499 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
500 	vchan_dma_desc_free_list(&tdc->vc, &head);
501 
502 	return 0;
503 }
504 
tegra_adma_tx_status(struct dma_chan * dc,dma_cookie_t cookie,struct dma_tx_state * txstate)505 static enum dma_status tegra_adma_tx_status(struct dma_chan *dc,
506 					    dma_cookie_t cookie,
507 					    struct dma_tx_state *txstate)
508 {
509 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
510 	struct tegra_adma_desc *desc;
511 	struct virt_dma_desc *vd;
512 	enum dma_status ret;
513 	unsigned long flags;
514 	unsigned int residual;
515 
516 	ret = dma_cookie_status(dc, cookie, txstate);
517 	if (ret == DMA_COMPLETE || !txstate)
518 		return ret;
519 
520 	spin_lock_irqsave(&tdc->vc.lock, flags);
521 
522 	vd = vchan_find_desc(&tdc->vc, cookie);
523 	if (vd) {
524 		desc = to_tegra_adma_desc(&vd->tx);
525 		residual = desc->ch_regs.tc;
526 	} else if (tdc->desc && tdc->desc->vd.tx.cookie == cookie) {
527 		residual = tegra_adma_get_residue(tdc);
528 	} else {
529 		residual = 0;
530 	}
531 
532 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
533 
534 	dma_set_residue(txstate, residual);
535 
536 	return ret;
537 }
538 
tegra210_adma_get_burst_config(unsigned int burst_size)539 static unsigned int tegra210_adma_get_burst_config(unsigned int burst_size)
540 {
541 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
542 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
543 
544 	return fls(burst_size) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
545 }
546 
tegra186_adma_get_burst_config(unsigned int burst_size)547 static unsigned int tegra186_adma_get_burst_config(unsigned int burst_size)
548 {
549 	if (!burst_size || burst_size > ADMA_CH_CONFIG_MAX_BURST_SIZE)
550 		burst_size = ADMA_CH_CONFIG_MAX_BURST_SIZE;
551 
552 	return (burst_size - 1) << ADMA_CH_CONFIG_BURST_SIZE_SHIFT;
553 }
554 
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)555 static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
556 				      struct tegra_adma_desc *desc,
557 				      dma_addr_t buf_addr,
558 				      enum dma_transfer_direction direction)
559 {
560 	struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
561 	const struct tegra_adma_chip_data *cdata = tdc->tdma->cdata;
562 	unsigned int burst_size, adma_dir, fifo_size_shift;
563 
564 	if (desc->num_periods > ADMA_CH_CONFIG_MAX_BUFS)
565 		return -EINVAL;
566 
567 	switch (direction) {
568 	case DMA_MEM_TO_DEV:
569 		fifo_size_shift = ADMA_CH_TX_FIFO_SIZE_SHIFT;
570 		adma_dir = ADMA_CH_CTRL_DIR_MEM2AHUB;
571 		burst_size = tdc->sconfig.dst_maxburst;
572 		ch_regs->config = ADMA_CH_CONFIG_SRC_BUF(desc->num_periods - 1);
573 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
574 						      cdata->ch_req_mask,
575 						      cdata->ch_req_tx_shift);
576 		ch_regs->src_addr = buf_addr;
577 		break;
578 
579 	case DMA_DEV_TO_MEM:
580 		fifo_size_shift = ADMA_CH_RX_FIFO_SIZE_SHIFT;
581 		adma_dir = ADMA_CH_CTRL_DIR_AHUB2MEM;
582 		burst_size = tdc->sconfig.src_maxburst;
583 		ch_regs->config = ADMA_CH_CONFIG_TRG_BUF(desc->num_periods - 1);
584 		ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
585 						      cdata->ch_req_mask,
586 						      cdata->ch_req_rx_shift);
587 		ch_regs->trg_addr = buf_addr;
588 		break;
589 
590 	default:
591 		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
592 		return -EINVAL;
593 	}
594 
595 	ch_regs->ctrl |= ADMA_CH_CTRL_DIR(adma_dir) |
596 			 ADMA_CH_CTRL_MODE_CONTINUOUS |
597 			 ADMA_CH_CTRL_FLOWCTRL_EN;
598 	ch_regs->config |= cdata->adma_get_burst_config(burst_size);
599 	ch_regs->config |= ADMA_CH_CONFIG_WEIGHT_FOR_WRR(1);
600 	if (cdata->has_outstanding_reqs)
601 		ch_regs->config |= TEGRA186_ADMA_CH_CONFIG_OUTSTANDING_REQS(8);
602 
603 	/*
604 	 * 'sreq_index' represents the current ADMAIF channel number and as per
605 	 * HW recommendation its FIFO size should match with the corresponding
606 	 * ADMA channel.
607 	 *
608 	 * ADMA FIFO size is set as per below (based on default ADMAIF channel
609 	 * FIFO sizes):
610 	 *    fifo_size = 0x2 (sreq_index > sreq_index_offset)
611 	 *    fifo_size = 0x3 (sreq_index <= sreq_index_offset)
612 	 *
613 	 */
614 	if (tdc->sreq_index > cdata->sreq_index_offset)
615 		ch_regs->fifo_ctrl =
616 			ADMA_CH_REG_FIELD_VAL(2, cdata->ch_fifo_size_mask,
617 					      fifo_size_shift);
618 	else
619 		ch_regs->fifo_ctrl =
620 			ADMA_CH_REG_FIELD_VAL(3, cdata->ch_fifo_size_mask,
621 					      fifo_size_shift);
622 
623 	ch_regs->tc = desc->period_len & ADMA_CH_TC_COUNT_MASK;
624 
625 	return tegra_adma_request_alloc(tdc, direction);
626 }
627 
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)628 static struct dma_async_tx_descriptor *tegra_adma_prep_dma_cyclic(
629 	struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
630 	size_t period_len, enum dma_transfer_direction direction,
631 	unsigned long flags)
632 {
633 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
634 	struct tegra_adma_desc *desc = NULL;
635 
636 	if (!buf_len || !period_len || period_len > ADMA_CH_TC_COUNT_MASK) {
637 		dev_err(tdc2dev(tdc), "invalid buffer/period len\n");
638 		return NULL;
639 	}
640 
641 	if (buf_len % period_len) {
642 		dev_err(tdc2dev(tdc), "buf_len not a multiple of period_len\n");
643 		return NULL;
644 	}
645 
646 	if (!IS_ALIGNED(buf_addr, 4)) {
647 		dev_err(tdc2dev(tdc), "invalid buffer alignment\n");
648 		return NULL;
649 	}
650 
651 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
652 	if (!desc)
653 		return NULL;
654 
655 	desc->buf_len = buf_len;
656 	desc->period_len = period_len;
657 	desc->num_periods = buf_len / period_len;
658 
659 	if (tegra_adma_set_xfer_params(tdc, desc, buf_addr, direction)) {
660 		kfree(desc);
661 		return NULL;
662 	}
663 
664 	return vchan_tx_prep(&tdc->vc, &desc->vd, flags);
665 }
666 
tegra_adma_alloc_chan_resources(struct dma_chan * dc)667 static int tegra_adma_alloc_chan_resources(struct dma_chan *dc)
668 {
669 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
670 	int ret;
671 
672 	ret = request_irq(tdc->irq, tegra_adma_isr, 0, dma_chan_name(dc), tdc);
673 	if (ret) {
674 		dev_err(tdc2dev(tdc), "failed to get interrupt for %s\n",
675 			dma_chan_name(dc));
676 		return ret;
677 	}
678 
679 	ret = pm_runtime_resume_and_get(tdc2dev(tdc));
680 	if (ret < 0) {
681 		free_irq(tdc->irq, tdc);
682 		return ret;
683 	}
684 
685 	dma_cookie_init(&tdc->vc.chan);
686 
687 	return 0;
688 }
689 
tegra_adma_free_chan_resources(struct dma_chan * dc)690 static void tegra_adma_free_chan_resources(struct dma_chan *dc)
691 {
692 	struct tegra_adma_chan *tdc = to_tegra_adma_chan(dc);
693 
694 	tegra_adma_terminate_all(dc);
695 	vchan_free_chan_resources(&tdc->vc);
696 	tasklet_kill(&tdc->vc.task);
697 	free_irq(tdc->irq, tdc);
698 	pm_runtime_put(tdc2dev(tdc));
699 
700 	tdc->sreq_index = 0;
701 	tdc->sreq_dir = DMA_TRANS_NONE;
702 }
703 
tegra_dma_of_xlate(struct of_phandle_args * dma_spec,struct of_dma * ofdma)704 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
705 					   struct of_dma *ofdma)
706 {
707 	struct tegra_adma *tdma = ofdma->of_dma_data;
708 	struct tegra_adma_chan *tdc;
709 	struct dma_chan *chan;
710 	unsigned int sreq_index;
711 
712 	if (dma_spec->args_count != 1)
713 		return NULL;
714 
715 	sreq_index = dma_spec->args[0];
716 
717 	if (sreq_index == 0) {
718 		dev_err(tdma->dev, "DMA request must not be 0\n");
719 		return NULL;
720 	}
721 
722 	chan = dma_get_any_slave_channel(&tdma->dma_dev);
723 	if (!chan)
724 		return NULL;
725 
726 	tdc = to_tegra_adma_chan(chan);
727 	tdc->sreq_index = sreq_index;
728 
729 	return chan;
730 }
731 
tegra_adma_runtime_suspend(struct device * dev)732 static int __maybe_unused tegra_adma_runtime_suspend(struct device *dev)
733 {
734 	struct tegra_adma *tdma = dev_get_drvdata(dev);
735 	struct tegra_adma_chan_regs *ch_reg;
736 	struct tegra_adma_chan *tdc;
737 	int i;
738 
739 	tdma->global_cmd = tdma_read(tdma, ADMA_GLOBAL_CMD);
740 	if (!tdma->global_cmd)
741 		goto clk_disable;
742 
743 	for (i = 0; i < tdma->nr_channels; i++) {
744 		tdc = &tdma->channels[i];
745 		/* skip for reserved channels */
746 		if (!tdc->tdma)
747 			continue;
748 
749 		ch_reg = &tdc->ch_regs;
750 		ch_reg->cmd = tdma_ch_read(tdc, ADMA_CH_CMD);
751 		/* skip if channel is not active */
752 		if (!ch_reg->cmd)
753 			continue;
754 		ch_reg->tc = tdma_ch_read(tdc, ADMA_CH_TC);
755 		ch_reg->src_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_SRC_ADDR);
756 		ch_reg->trg_addr = tdma_ch_read(tdc, ADMA_CH_LOWER_TRG_ADDR);
757 		ch_reg->ctrl = tdma_ch_read(tdc, ADMA_CH_CTRL);
758 		ch_reg->fifo_ctrl = tdma_ch_read(tdc, ADMA_CH_FIFO_CTRL);
759 		ch_reg->config = tdma_ch_read(tdc, ADMA_CH_CONFIG);
760 	}
761 
762 clk_disable:
763 	clk_disable_unprepare(tdma->ahub_clk);
764 
765 	return 0;
766 }
767 
tegra_adma_runtime_resume(struct device * dev)768 static int __maybe_unused tegra_adma_runtime_resume(struct device *dev)
769 {
770 	struct tegra_adma *tdma = dev_get_drvdata(dev);
771 	struct tegra_adma_chan_regs *ch_reg;
772 	struct tegra_adma_chan *tdc;
773 	int ret, i;
774 
775 	ret = clk_prepare_enable(tdma->ahub_clk);
776 	if (ret) {
777 		dev_err(dev, "ahub clk_enable failed: %d\n", ret);
778 		return ret;
779 	}
780 	tdma_write(tdma, ADMA_GLOBAL_CMD, tdma->global_cmd);
781 
782 	if (!tdma->global_cmd)
783 		return 0;
784 
785 	for (i = 0; i < tdma->nr_channels; i++) {
786 		tdc = &tdma->channels[i];
787 		/* skip for reserved channels */
788 		if (!tdc->tdma)
789 			continue;
790 		ch_reg = &tdc->ch_regs;
791 		/* skip if channel was not active earlier */
792 		if (!ch_reg->cmd)
793 			continue;
794 		tdma_ch_write(tdc, ADMA_CH_TC, ch_reg->tc);
795 		tdma_ch_write(tdc, ADMA_CH_LOWER_SRC_ADDR, ch_reg->src_addr);
796 		tdma_ch_write(tdc, ADMA_CH_LOWER_TRG_ADDR, ch_reg->trg_addr);
797 		tdma_ch_write(tdc, ADMA_CH_CTRL, ch_reg->ctrl);
798 		tdma_ch_write(tdc, ADMA_CH_FIFO_CTRL, ch_reg->fifo_ctrl);
799 		tdma_ch_write(tdc, ADMA_CH_CONFIG, ch_reg->config);
800 		tdma_ch_write(tdc, ADMA_CH_CMD, ch_reg->cmd);
801 	}
802 
803 	return 0;
804 }
805 
806 static const struct tegra_adma_chip_data tegra210_chip_data = {
807 	.adma_get_burst_config  = tegra210_adma_get_burst_config,
808 	.global_reg_offset	= 0xc00,
809 	.global_int_clear	= 0x20,
810 	.ch_req_tx_shift	= 28,
811 	.ch_req_rx_shift	= 24,
812 	.ch_base_offset		= 0,
813 	.ch_req_mask		= 0xf,
814 	.ch_req_max		= 10,
815 	.ch_reg_size		= 0x80,
816 	.nr_channels		= 22,
817 	.ch_fifo_size_mask	= 0xf,
818 	.sreq_index_offset	= 2,
819 	.has_outstanding_reqs	= false,
820 };
821 
822 static const struct tegra_adma_chip_data tegra186_chip_data = {
823 	.adma_get_burst_config  = tegra186_adma_get_burst_config,
824 	.global_reg_offset	= 0,
825 	.global_int_clear	= 0x402c,
826 	.ch_req_tx_shift	= 27,
827 	.ch_req_rx_shift	= 22,
828 	.ch_base_offset		= 0x10000,
829 	.ch_req_mask		= 0x1f,
830 	.ch_req_max		= 20,
831 	.ch_reg_size		= 0x100,
832 	.nr_channels		= 32,
833 	.ch_fifo_size_mask	= 0x1f,
834 	.sreq_index_offset	= 4,
835 	.has_outstanding_reqs	= true,
836 };
837 
838 static const struct of_device_id tegra_adma_of_match[] = {
839 	{ .compatible = "nvidia,tegra210-adma", .data = &tegra210_chip_data },
840 	{ .compatible = "nvidia,tegra186-adma", .data = &tegra186_chip_data },
841 	{ },
842 };
843 MODULE_DEVICE_TABLE(of, tegra_adma_of_match);
844 
tegra_adma_probe(struct platform_device * pdev)845 static int tegra_adma_probe(struct platform_device *pdev)
846 {
847 	const struct tegra_adma_chip_data *cdata;
848 	struct tegra_adma *tdma;
849 	int ret, i;
850 
851 	cdata = of_device_get_match_data(&pdev->dev);
852 	if (!cdata) {
853 		dev_err(&pdev->dev, "device match data not found\n");
854 		return -ENODEV;
855 	}
856 
857 	tdma = devm_kzalloc(&pdev->dev,
858 			    struct_size(tdma, channels, cdata->nr_channels),
859 			    GFP_KERNEL);
860 	if (!tdma)
861 		return -ENOMEM;
862 
863 	tdma->dev = &pdev->dev;
864 	tdma->cdata = cdata;
865 	tdma->nr_channels = cdata->nr_channels;
866 	platform_set_drvdata(pdev, tdma);
867 
868 	tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
869 	if (IS_ERR(tdma->base_addr))
870 		return PTR_ERR(tdma->base_addr);
871 
872 	tdma->ahub_clk = devm_clk_get(&pdev->dev, "d_audio");
873 	if (IS_ERR(tdma->ahub_clk)) {
874 		dev_err(&pdev->dev, "Error: Missing ahub controller clock\n");
875 		return PTR_ERR(tdma->ahub_clk);
876 	}
877 
878 	tdma->dma_chan_mask = devm_kzalloc(&pdev->dev,
879 					   BITS_TO_LONGS(tdma->nr_channels) * sizeof(unsigned long),
880 					   GFP_KERNEL);
881 	if (!tdma->dma_chan_mask)
882 		return -ENOMEM;
883 
884 	/* Enable all channels by default */
885 	bitmap_fill(tdma->dma_chan_mask, tdma->nr_channels);
886 
887 	ret = of_property_read_u32_array(pdev->dev.of_node, "dma-channel-mask",
888 					 (u32 *)tdma->dma_chan_mask,
889 					 BITS_TO_U32(tdma->nr_channels));
890 	if (ret < 0 && (ret != -EINVAL)) {
891 		dev_err(&pdev->dev, "dma-channel-mask is not complete.\n");
892 		return ret;
893 	}
894 
895 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
896 	for (i = 0; i < tdma->nr_channels; i++) {
897 		struct tegra_adma_chan *tdc = &tdma->channels[i];
898 
899 		/* skip for reserved channels */
900 		if (!test_bit(i, tdma->dma_chan_mask))
901 			continue;
902 
903 		tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
904 				 + (cdata->ch_reg_size * i);
905 
906 		tdc->irq = of_irq_get(pdev->dev.of_node, i);
907 		if (tdc->irq <= 0) {
908 			ret = tdc->irq ?: -ENXIO;
909 			goto irq_dispose;
910 		}
911 
912 		vchan_init(&tdc->vc, &tdma->dma_dev);
913 		tdc->vc.desc_free = tegra_adma_desc_free;
914 		tdc->tdma = tdma;
915 	}
916 
917 	pm_runtime_enable(&pdev->dev);
918 
919 	ret = pm_runtime_resume_and_get(&pdev->dev);
920 	if (ret < 0)
921 		goto rpm_disable;
922 
923 	ret = tegra_adma_init(tdma);
924 	if (ret)
925 		goto rpm_put;
926 
927 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
928 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
929 	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
930 
931 	tdma->dma_dev.dev = &pdev->dev;
932 	tdma->dma_dev.device_alloc_chan_resources =
933 					tegra_adma_alloc_chan_resources;
934 	tdma->dma_dev.device_free_chan_resources =
935 					tegra_adma_free_chan_resources;
936 	tdma->dma_dev.device_issue_pending = tegra_adma_issue_pending;
937 	tdma->dma_dev.device_prep_dma_cyclic = tegra_adma_prep_dma_cyclic;
938 	tdma->dma_dev.device_config = tegra_adma_slave_config;
939 	tdma->dma_dev.device_tx_status = tegra_adma_tx_status;
940 	tdma->dma_dev.device_terminate_all = tegra_adma_terminate_all;
941 	tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
942 	tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
943 	tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
944 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
945 	tdma->dma_dev.device_pause = tegra_adma_pause;
946 	tdma->dma_dev.device_resume = tegra_adma_resume;
947 
948 	ret = dma_async_device_register(&tdma->dma_dev);
949 	if (ret < 0) {
950 		dev_err(&pdev->dev, "ADMA registration failed: %d\n", ret);
951 		goto rpm_put;
952 	}
953 
954 	ret = of_dma_controller_register(pdev->dev.of_node,
955 					 tegra_dma_of_xlate, tdma);
956 	if (ret < 0) {
957 		dev_err(&pdev->dev, "ADMA OF registration failed %d\n", ret);
958 		goto dma_remove;
959 	}
960 
961 	pm_runtime_put(&pdev->dev);
962 
963 	dev_info(&pdev->dev, "Tegra210 ADMA driver registered %d channels\n",
964 		 tdma->nr_channels);
965 
966 	return 0;
967 
968 dma_remove:
969 	dma_async_device_unregister(&tdma->dma_dev);
970 rpm_put:
971 	pm_runtime_put_sync(&pdev->dev);
972 rpm_disable:
973 	pm_runtime_disable(&pdev->dev);
974 irq_dispose:
975 	while (--i >= 0)
976 		irq_dispose_mapping(tdma->channels[i].irq);
977 
978 	return ret;
979 }
980 
tegra_adma_remove(struct platform_device * pdev)981 static void tegra_adma_remove(struct platform_device *pdev)
982 {
983 	struct tegra_adma *tdma = platform_get_drvdata(pdev);
984 	int i;
985 
986 	of_dma_controller_free(pdev->dev.of_node);
987 	dma_async_device_unregister(&tdma->dma_dev);
988 
989 	for (i = 0; i < tdma->nr_channels; ++i) {
990 		if (tdma->channels[i].irq)
991 			irq_dispose_mapping(tdma->channels[i].irq);
992 	}
993 
994 	pm_runtime_disable(&pdev->dev);
995 }
996 
997 static const struct dev_pm_ops tegra_adma_dev_pm_ops = {
998 	SET_RUNTIME_PM_OPS(tegra_adma_runtime_suspend,
999 			   tegra_adma_runtime_resume, NULL)
1000 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1001 				     pm_runtime_force_resume)
1002 };
1003 
1004 static struct platform_driver tegra_admac_driver = {
1005 	.driver = {
1006 		.name	= "tegra-adma",
1007 		.pm	= &tegra_adma_dev_pm_ops,
1008 		.of_match_table = tegra_adma_of_match,
1009 	},
1010 	.probe		= tegra_adma_probe,
1011 	.remove_new	= tegra_adma_remove,
1012 };
1013 
1014 module_platform_driver(tegra_admac_driver);
1015 
1016 MODULE_ALIAS("platform:tegra210-adma");
1017 MODULE_DESCRIPTION("NVIDIA Tegra ADMA driver");
1018 MODULE_AUTHOR("Dara Ramesh <dramesh@nvidia.com>");
1019 MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
1020 MODULE_LICENSE("GPL v2");
1021