1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * DMA driver for NVIDIA Tegra GPC DMA controller.
4  *
5  * Copyright (c) 2014-2022, NVIDIA CORPORATION.  All rights reserved.
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/iommu.h>
13 #include <linux/iopoll.h>
14 #include <linux/minmax.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/of_dma.h>
18 #include <linux/platform_device.h>
19 #include <linux/reset.h>
20 #include <linux/slab.h>
21 #include <dt-bindings/memory/tegra186-mc.h>
22 #include "virt-dma.h"
23 
24 /* CSR register */
25 #define TEGRA_GPCDMA_CHAN_CSR			0x00
26 #define TEGRA_GPCDMA_CSR_ENB			BIT(31)
27 #define TEGRA_GPCDMA_CSR_IE_EOC			BIT(30)
28 #define TEGRA_GPCDMA_CSR_ONCE			BIT(27)
29 
30 #define TEGRA_GPCDMA_CSR_FC_MODE		GENMASK(25, 24)
31 #define TEGRA_GPCDMA_CSR_FC_MODE_NO_MMIO	\
32 		FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 0)
33 #define TEGRA_GPCDMA_CSR_FC_MODE_ONE_MMIO	\
34 		FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 1)
35 #define TEGRA_GPCDMA_CSR_FC_MODE_TWO_MMIO	\
36 		FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 2)
37 #define TEGRA_GPCDMA_CSR_FC_MODE_FOUR_MMIO	\
38 		FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 3)
39 
40 #define TEGRA_GPCDMA_CSR_DMA			GENMASK(23, 21)
41 #define TEGRA_GPCDMA_CSR_DMA_IO2MEM_NO_FC	\
42 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 0)
43 #define TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC		\
44 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 1)
45 #define TEGRA_GPCDMA_CSR_DMA_MEM2IO_NO_FC	\
46 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 2)
47 #define TEGRA_GPCDMA_CSR_DMA_MEM2IO_FC		\
48 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 3)
49 #define TEGRA_GPCDMA_CSR_DMA_MEM2MEM		\
50 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 4)
51 #define TEGRA_GPCDMA_CSR_DMA_FIXED_PAT		\
52 		FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 6)
53 
54 #define TEGRA_GPCDMA_CSR_REQ_SEL_MASK		GENMASK(20, 16)
55 #define TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED		\
56 					FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, 4)
57 #define TEGRA_GPCDMA_CSR_IRQ_MASK		BIT(15)
58 #define TEGRA_GPCDMA_CSR_WEIGHT			GENMASK(13, 10)
59 
60 /* STATUS register */
61 #define TEGRA_GPCDMA_CHAN_STATUS		0x004
62 #define TEGRA_GPCDMA_STATUS_BUSY		BIT(31)
63 #define TEGRA_GPCDMA_STATUS_ISE_EOC		BIT(30)
64 #define TEGRA_GPCDMA_STATUS_PING_PONG		BIT(28)
65 #define TEGRA_GPCDMA_STATUS_DMA_ACTIVITY	BIT(27)
66 #define TEGRA_GPCDMA_STATUS_CHANNEL_PAUSE	BIT(26)
67 #define TEGRA_GPCDMA_STATUS_CHANNEL_RX		BIT(25)
68 #define TEGRA_GPCDMA_STATUS_CHANNEL_TX		BIT(24)
69 #define TEGRA_GPCDMA_STATUS_IRQ_INTR_STA	BIT(23)
70 #define TEGRA_GPCDMA_STATUS_IRQ_STA		BIT(21)
71 #define TEGRA_GPCDMA_STATUS_IRQ_TRIG_STA	BIT(20)
72 
73 #define TEGRA_GPCDMA_CHAN_CSRE			0x008
74 #define TEGRA_GPCDMA_CHAN_CSRE_PAUSE		BIT(31)
75 
76 /* Source address */
77 #define TEGRA_GPCDMA_CHAN_SRC_PTR		0x00C
78 
79 /* Destination address */
80 #define TEGRA_GPCDMA_CHAN_DST_PTR		0x010
81 
82 /* High address pointer */
83 #define TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR		0x014
84 #define TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR		GENMASK(7, 0)
85 #define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR		GENMASK(23, 16)
86 
87 /* MC sequence register */
88 #define TEGRA_GPCDMA_CHAN_MCSEQ			0x18
89 #define TEGRA_GPCDMA_MCSEQ_DATA_SWAP		BIT(31)
90 #define TEGRA_GPCDMA_MCSEQ_REQ_COUNT		GENMASK(30, 25)
91 #define TEGRA_GPCDMA_MCSEQ_BURST		GENMASK(24, 23)
92 #define TEGRA_GPCDMA_MCSEQ_BURST_2		\
93 		FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 0)
94 #define TEGRA_GPCDMA_MCSEQ_BURST_16		\
95 		FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 3)
96 #define TEGRA_GPCDMA_MCSEQ_WRAP1		GENMASK(22, 20)
97 #define TEGRA_GPCDMA_MCSEQ_WRAP0		GENMASK(19, 17)
98 #define TEGRA_GPCDMA_MCSEQ_WRAP_NONE		0
99 
100 #define TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK	GENMASK(13, 7)
101 #define TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK	GENMASK(6, 0)
102 
103 /* MMIO sequence register */
104 #define TEGRA_GPCDMA_CHAN_MMIOSEQ			0x01c
105 #define TEGRA_GPCDMA_MMIOSEQ_DBL_BUF		BIT(31)
106 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH		GENMASK(30, 28)
107 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8	\
108 		FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 0)
109 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16	\
110 		FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 1)
111 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32	\
112 		FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 2)
113 #define TEGRA_GPCDMA_MMIOSEQ_DATA_SWAP		BIT(27)
114 #define TEGRA_GPCDMA_MMIOSEQ_BURST_SHIFT	23
115 #define TEGRA_GPCDMA_MMIOSEQ_BURST_MIN		2U
116 #define TEGRA_GPCDMA_MMIOSEQ_BURST_MAX		32U
117 #define TEGRA_GPCDMA_MMIOSEQ_BURST(bs)	\
118 		(GENMASK((fls(bs) - 2), 0) << TEGRA_GPCDMA_MMIOSEQ_BURST_SHIFT)
119 #define TEGRA_GPCDMA_MMIOSEQ_MASTER_ID		GENMASK(22, 19)
120 #define TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD		GENMASK(18, 16)
121 #define TEGRA_GPCDMA_MMIOSEQ_MMIO_PROT		GENMASK(8, 7)
122 
123 /* Channel WCOUNT */
124 #define TEGRA_GPCDMA_CHAN_WCOUNT		0x20
125 
126 /* Transfer count */
127 #define TEGRA_GPCDMA_CHAN_XFER_COUNT		0x24
128 
129 /* DMA byte count status */
130 #define TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS	0x28
131 
132 /* Error Status Register */
133 #define TEGRA_GPCDMA_CHAN_ERR_STATUS		0x30
134 #define TEGRA_GPCDMA_CHAN_ERR_TYPE_SHIFT	8
135 #define TEGRA_GPCDMA_CHAN_ERR_TYPE_MASK	0xF
136 #define TEGRA_GPCDMA_CHAN_ERR_TYPE(err)	(			\
137 		((err) >> TEGRA_GPCDMA_CHAN_ERR_TYPE_SHIFT) &	\
138 		TEGRA_GPCDMA_CHAN_ERR_TYPE_MASK)
139 #define TEGRA_DMA_BM_FIFO_FULL_ERR		0xF
140 #define TEGRA_DMA_PERIPH_FIFO_FULL_ERR		0xE
141 #define TEGRA_DMA_PERIPH_ID_ERR			0xD
142 #define TEGRA_DMA_STREAM_ID_ERR			0xC
143 #define TEGRA_DMA_MC_SLAVE_ERR			0xB
144 #define TEGRA_DMA_MMIO_SLAVE_ERR		0xA
145 
146 /* Fixed Pattern */
147 #define TEGRA_GPCDMA_CHAN_FIXED_PATTERN		0x34
148 
149 #define TEGRA_GPCDMA_CHAN_TZ			0x38
150 #define TEGRA_GPCDMA_CHAN_TZ_MMIO_PROT_1	BIT(0)
151 #define TEGRA_GPCDMA_CHAN_TZ_MC_PROT_1		BIT(1)
152 
153 #define TEGRA_GPCDMA_CHAN_SPARE			0x3c
154 #define TEGRA_GPCDMA_CHAN_SPARE_EN_LEGACY_FC	BIT(16)
155 
156 /*
157  * If any burst is in flight and DMA paused then this is the time to complete
158  * on-flight burst and update DMA status register.
159  */
160 #define TEGRA_GPCDMA_BURST_COMPLETE_TIME	10
161 #define TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT	5000 /* 5 msec */
162 
163 /* Channel base address offset from GPCDMA base address */
164 #define TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET	0x10000
165 
166 /* Default channel mask reserving channel0 */
167 #define TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK	0xfffffffe
168 
169 struct tegra_dma;
170 struct tegra_dma_channel;
171 
172 /*
173  * tegra_dma_chip_data Tegra chip specific DMA data
174  * @nr_channels: Number of channels available in the controller.
175  * @channel_reg_size: Channel register size.
176  * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
177  * @hw_support_pause: DMA HW engine support pause of the channel.
178  */
179 struct tegra_dma_chip_data {
180 	bool hw_support_pause;
181 	unsigned int nr_channels;
182 	unsigned int channel_reg_size;
183 	unsigned int max_dma_count;
184 	int (*terminate)(struct tegra_dma_channel *tdc);
185 };
186 
187 /* DMA channel registers */
188 struct tegra_dma_channel_regs {
189 	u32 csr;
190 	u32 src_ptr;
191 	u32 dst_ptr;
192 	u32 high_addr_ptr;
193 	u32 mc_seq;
194 	u32 mmio_seq;
195 	u32 wcount;
196 	u32 fixed_pattern;
197 };
198 
199 /*
200  * tegra_dma_sg_req: DMA request details to configure hardware. This
201  * contains the details for one transfer to configure DMA hw.
202  * The client's request for data transfer can be broken into multiple
203  * sub-transfer as per requester details and hw support. This sub transfer
204  * get added as an array in Tegra DMA desc which manages the transfer details.
205  */
206 struct tegra_dma_sg_req {
207 	unsigned int len;
208 	struct tegra_dma_channel_regs ch_regs;
209 };
210 
211 /*
212  * tegra_dma_desc: Tegra DMA descriptors which uses virt_dma_desc to
213  * manage client request and keep track of transfer status, callbacks
214  * and request counts etc.
215  */
216 struct tegra_dma_desc {
217 	bool cyclic;
218 	unsigned int bytes_req;
219 	unsigned int bytes_xfer;
220 	unsigned int sg_idx;
221 	unsigned int sg_count;
222 	struct virt_dma_desc vd;
223 	struct tegra_dma_channel *tdc;
224 	struct tegra_dma_sg_req sg_req[];
225 };
226 
227 /*
228  * tegra_dma_channel: Channel specific information
229  */
230 struct tegra_dma_channel {
231 	bool config_init;
232 	char name[30];
233 	enum dma_transfer_direction sid_dir;
234 	int id;
235 	int irq;
236 	int slave_id;
237 	struct tegra_dma *tdma;
238 	struct virt_dma_chan vc;
239 	struct tegra_dma_desc *dma_desc;
240 	struct dma_slave_config dma_sconfig;
241 	unsigned int stream_id;
242 	unsigned long chan_base_offset;
243 };
244 
245 /*
246  * tegra_dma: Tegra DMA specific information
247  */
248 struct tegra_dma {
249 	const struct tegra_dma_chip_data *chip_data;
250 	unsigned long sid_m2d_reserved;
251 	unsigned long sid_d2m_reserved;
252 	u32 chan_mask;
253 	void __iomem *base_addr;
254 	struct device *dev;
255 	struct dma_device dma_dev;
256 	struct reset_control *rst;
257 	struct tegra_dma_channel channels[];
258 };
259 
260 static inline void tdc_write(struct tegra_dma_channel *tdc,
261 			     u32 reg, u32 val)
262 {
263 	writel_relaxed(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg);
264 }
265 
266 static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
267 {
268 	return readl_relaxed(tdc->tdma->base_addr + tdc->chan_base_offset + reg);
269 }
270 
271 static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc)
272 {
273 	return container_of(dc, struct tegra_dma_channel, vc.chan);
274 }
275 
276 static inline struct tegra_dma_desc *vd_to_tegra_dma_desc(struct virt_dma_desc *vd)
277 {
278 	return container_of(vd, struct tegra_dma_desc, vd);
279 }
280 
281 static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
282 {
283 	return tdc->vc.chan.device->dev;
284 }
285 
286 static void tegra_dma_dump_chan_regs(struct tegra_dma_channel *tdc)
287 {
288 	dev_dbg(tdc2dev(tdc), "DMA Channel %d name %s register dump:\n",
289 		tdc->id, tdc->name);
290 	dev_dbg(tdc2dev(tdc), "CSR %x STA %x CSRE %x SRC %x DST %x\n",
291 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR),
292 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS),
293 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE),
294 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR),
295 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_DST_PTR)
296 	);
297 	dev_dbg(tdc2dev(tdc), "MCSEQ %x IOSEQ %x WCNT %x XFER %x BSTA %x\n",
298 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ),
299 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ),
300 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_WCOUNT),
301 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT),
302 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS)
303 	);
304 	dev_dbg(tdc2dev(tdc), "DMA ERR_STA %x\n",
305 		tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS));
306 }
307 
308 static int tegra_dma_sid_reserve(struct tegra_dma_channel *tdc,
309 				 enum dma_transfer_direction direction)
310 {
311 	struct tegra_dma *tdma = tdc->tdma;
312 	int sid = tdc->slave_id;
313 
314 	if (!is_slave_direction(direction))
315 		return 0;
316 
317 	switch (direction) {
318 	case DMA_MEM_TO_DEV:
319 		if (test_and_set_bit(sid, &tdma->sid_m2d_reserved)) {
320 			dev_err(tdma->dev, "slave id already in use\n");
321 			return -EINVAL;
322 		}
323 		break;
324 	case DMA_DEV_TO_MEM:
325 		if (test_and_set_bit(sid, &tdma->sid_d2m_reserved)) {
326 			dev_err(tdma->dev, "slave id already in use\n");
327 			return -EINVAL;
328 		}
329 		break;
330 	default:
331 		break;
332 	}
333 
334 	tdc->sid_dir = direction;
335 
336 	return 0;
337 }
338 
339 static void tegra_dma_sid_free(struct tegra_dma_channel *tdc)
340 {
341 	struct tegra_dma *tdma = tdc->tdma;
342 	int sid = tdc->slave_id;
343 
344 	switch (tdc->sid_dir) {
345 	case DMA_MEM_TO_DEV:
346 		clear_bit(sid,  &tdma->sid_m2d_reserved);
347 		break;
348 	case DMA_DEV_TO_MEM:
349 		clear_bit(sid,  &tdma->sid_d2m_reserved);
350 		break;
351 	default:
352 		break;
353 	}
354 
355 	tdc->sid_dir = DMA_TRANS_NONE;
356 }
357 
358 static void tegra_dma_desc_free(struct virt_dma_desc *vd)
359 {
360 	kfree(container_of(vd, struct tegra_dma_desc, vd));
361 }
362 
363 static int tegra_dma_slave_config(struct dma_chan *dc,
364 				  struct dma_slave_config *sconfig)
365 {
366 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
367 
368 	memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
369 	tdc->config_init = true;
370 
371 	return 0;
372 }
373 
374 static int tegra_dma_pause(struct tegra_dma_channel *tdc)
375 {
376 	int ret;
377 	u32 val;
378 
379 	val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE);
380 	val |= TEGRA_GPCDMA_CHAN_CSRE_PAUSE;
381 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, val);
382 
383 	/* Wait until busy bit is de-asserted */
384 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
385 			tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS,
386 			val,
387 			!(val & TEGRA_GPCDMA_STATUS_BUSY),
388 			TEGRA_GPCDMA_BURST_COMPLETE_TIME,
389 			TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT);
390 
391 	if (ret) {
392 		dev_err(tdc2dev(tdc), "DMA pause timed out\n");
393 		tegra_dma_dump_chan_regs(tdc);
394 	}
395 
396 	return ret;
397 }
398 
399 static int tegra_dma_device_pause(struct dma_chan *dc)
400 {
401 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
402 	unsigned long flags;
403 	int ret;
404 
405 	if (!tdc->tdma->chip_data->hw_support_pause)
406 		return -ENOSYS;
407 
408 	spin_lock_irqsave(&tdc->vc.lock, flags);
409 	ret = tegra_dma_pause(tdc);
410 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
411 
412 	return ret;
413 }
414 
415 static void tegra_dma_resume(struct tegra_dma_channel *tdc)
416 {
417 	u32 val;
418 
419 	val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE);
420 	val &= ~TEGRA_GPCDMA_CHAN_CSRE_PAUSE;
421 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, val);
422 }
423 
424 static int tegra_dma_device_resume(struct dma_chan *dc)
425 {
426 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
427 	unsigned long flags;
428 
429 	if (!tdc->tdma->chip_data->hw_support_pause)
430 		return -ENOSYS;
431 
432 	spin_lock_irqsave(&tdc->vc.lock, flags);
433 	tegra_dma_resume(tdc);
434 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
435 
436 	return 0;
437 }
438 
439 static inline int tegra_dma_pause_noerr(struct tegra_dma_channel *tdc)
440 {
441 	/* Return 0 irrespective of PAUSE status.
442 	 * This is useful to recover channels that can exit out of flush
443 	 * state when the channel is disabled.
444 	 */
445 
446 	tegra_dma_pause(tdc);
447 	return 0;
448 }
449 
450 static void tegra_dma_disable(struct tegra_dma_channel *tdc)
451 {
452 	u32 csr, status;
453 
454 	csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
455 
456 	/* Disable interrupts */
457 	csr &= ~TEGRA_GPCDMA_CSR_IE_EOC;
458 
459 	/* Disable DMA */
460 	csr &= ~TEGRA_GPCDMA_CSR_ENB;
461 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
462 
463 	/* Clear interrupt status if it is there */
464 	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
465 	if (status & TEGRA_GPCDMA_STATUS_ISE_EOC) {
466 		dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
467 		tdc_write(tdc, TEGRA_GPCDMA_CHAN_STATUS, status);
468 	}
469 }
470 
471 static void tegra_dma_configure_next_sg(struct tegra_dma_channel *tdc)
472 {
473 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
474 	struct tegra_dma_channel_regs *ch_regs;
475 	int ret;
476 	u32 val;
477 
478 	dma_desc->sg_idx++;
479 
480 	/* Reset the sg index for cyclic transfers */
481 	if (dma_desc->sg_idx == dma_desc->sg_count)
482 		dma_desc->sg_idx = 0;
483 
484 	/* Configure next transfer immediately after DMA is busy */
485 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
486 			tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS,
487 			val,
488 			(val & TEGRA_GPCDMA_STATUS_BUSY), 0,
489 			TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT);
490 	if (ret)
491 		return;
492 
493 	ch_regs = &dma_desc->sg_req[dma_desc->sg_idx].ch_regs;
494 
495 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_WCOUNT, ch_regs->wcount);
496 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_regs->src_ptr);
497 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_regs->dst_ptr);
498 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR, ch_regs->high_addr_ptr);
499 
500 	/* Start DMA */
501 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
502 		  ch_regs->csr | TEGRA_GPCDMA_CSR_ENB);
503 }
504 
505 static void tegra_dma_start(struct tegra_dma_channel *tdc)
506 {
507 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
508 	struct tegra_dma_channel_regs *ch_regs;
509 	struct virt_dma_desc *vdesc;
510 
511 	if (!dma_desc) {
512 		vdesc = vchan_next_desc(&tdc->vc);
513 		if (!vdesc)
514 			return;
515 
516 		dma_desc = vd_to_tegra_dma_desc(vdesc);
517 		list_del(&vdesc->node);
518 		dma_desc->tdc = tdc;
519 		tdc->dma_desc = dma_desc;
520 
521 		tegra_dma_resume(tdc);
522 	}
523 
524 	ch_regs = &dma_desc->sg_req[dma_desc->sg_idx].ch_regs;
525 
526 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_WCOUNT, ch_regs->wcount);
527 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, 0);
528 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_regs->src_ptr);
529 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_regs->dst_ptr);
530 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR, ch_regs->high_addr_ptr);
531 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_FIXED_PATTERN, ch_regs->fixed_pattern);
532 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ, ch_regs->mmio_seq);
533 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, ch_regs->mc_seq);
534 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, ch_regs->csr);
535 
536 	/* Start DMA */
537 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
538 		  ch_regs->csr | TEGRA_GPCDMA_CSR_ENB);
539 }
540 
541 static void tegra_dma_xfer_complete(struct tegra_dma_channel *tdc)
542 {
543 	vchan_cookie_complete(&tdc->dma_desc->vd);
544 
545 	tegra_dma_sid_free(tdc);
546 	tdc->dma_desc = NULL;
547 }
548 
549 static void tegra_dma_chan_decode_error(struct tegra_dma_channel *tdc,
550 					unsigned int err_status)
551 {
552 	switch (TEGRA_GPCDMA_CHAN_ERR_TYPE(err_status)) {
553 	case TEGRA_DMA_BM_FIFO_FULL_ERR:
554 		dev_err(tdc->tdma->dev,
555 			"GPCDMA CH%d bm fifo full\n", tdc->id);
556 		break;
557 
558 	case TEGRA_DMA_PERIPH_FIFO_FULL_ERR:
559 		dev_err(tdc->tdma->dev,
560 			"GPCDMA CH%d peripheral fifo full\n", tdc->id);
561 		break;
562 
563 	case TEGRA_DMA_PERIPH_ID_ERR:
564 		dev_err(tdc->tdma->dev,
565 			"GPCDMA CH%d illegal peripheral id\n", tdc->id);
566 		break;
567 
568 	case TEGRA_DMA_STREAM_ID_ERR:
569 		dev_err(tdc->tdma->dev,
570 			"GPCDMA CH%d illegal stream id\n", tdc->id);
571 		break;
572 
573 	case TEGRA_DMA_MC_SLAVE_ERR:
574 		dev_err(tdc->tdma->dev,
575 			"GPCDMA CH%d mc slave error\n", tdc->id);
576 		break;
577 
578 	case TEGRA_DMA_MMIO_SLAVE_ERR:
579 		dev_err(tdc->tdma->dev,
580 			"GPCDMA CH%d mmio slave error\n", tdc->id);
581 		break;
582 
583 	default:
584 		dev_err(tdc->tdma->dev,
585 			"GPCDMA CH%d security violation %x\n", tdc->id,
586 			err_status);
587 	}
588 }
589 
590 static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
591 {
592 	struct tegra_dma_channel *tdc = dev_id;
593 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
594 	struct tegra_dma_sg_req *sg_req;
595 	u32 status;
596 
597 	/* Check channel error status register */
598 	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS);
599 	if (status) {
600 		tegra_dma_chan_decode_error(tdc, status);
601 		tegra_dma_dump_chan_regs(tdc);
602 		tdc_write(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS, 0xFFFFFFFF);
603 	}
604 
605 	spin_lock(&tdc->vc.lock);
606 	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
607 	if (!(status & TEGRA_GPCDMA_STATUS_ISE_EOC))
608 		goto irq_done;
609 
610 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_STATUS,
611 		  TEGRA_GPCDMA_STATUS_ISE_EOC);
612 
613 	if (!dma_desc)
614 		goto irq_done;
615 
616 	sg_req = dma_desc->sg_req;
617 	dma_desc->bytes_xfer += sg_req[dma_desc->sg_idx].len;
618 
619 	if (dma_desc->cyclic) {
620 		vchan_cyclic_callback(&dma_desc->vd);
621 		tegra_dma_configure_next_sg(tdc);
622 	} else {
623 		dma_desc->sg_idx++;
624 		if (dma_desc->sg_idx == dma_desc->sg_count)
625 			tegra_dma_xfer_complete(tdc);
626 		else
627 			tegra_dma_start(tdc);
628 	}
629 
630 irq_done:
631 	spin_unlock(&tdc->vc.lock);
632 	return IRQ_HANDLED;
633 }
634 
635 static void tegra_dma_issue_pending(struct dma_chan *dc)
636 {
637 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
638 	unsigned long flags;
639 
640 	if (tdc->dma_desc)
641 		return;
642 
643 	spin_lock_irqsave(&tdc->vc.lock, flags);
644 	if (vchan_issue_pending(&tdc->vc))
645 		tegra_dma_start(tdc);
646 
647 	/*
648 	 * For cyclic DMA transfers, program the second
649 	 * transfer parameters as soon as the first DMA
650 	 * transfer is started inorder for the DMA
651 	 * controller to trigger the second transfer
652 	 * with the correct parameters.
653 	 */
654 	if (tdc->dma_desc && tdc->dma_desc->cyclic)
655 		tegra_dma_configure_next_sg(tdc);
656 
657 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
658 }
659 
660 static int tegra_dma_stop_client(struct tegra_dma_channel *tdc)
661 {
662 	int ret;
663 	u32 status, csr;
664 
665 	/*
666 	 * Change the client associated with the DMA channel
667 	 * to stop DMA engine from starting any more bursts for
668 	 * the given client and wait for in flight bursts to complete
669 	 */
670 	csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
671 	csr &= ~(TEGRA_GPCDMA_CSR_REQ_SEL_MASK);
672 	csr |= TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED;
673 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
674 
675 	/* Wait for in flight data transfer to finish */
676 	udelay(TEGRA_GPCDMA_BURST_COMPLETE_TIME);
677 
678 	/* If TX/RX path is still active wait till it becomes
679 	 * inactive
680 	 */
681 
682 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
683 				tdc->chan_base_offset +
684 				TEGRA_GPCDMA_CHAN_STATUS,
685 				status,
686 				!(status & (TEGRA_GPCDMA_STATUS_CHANNEL_TX |
687 				TEGRA_GPCDMA_STATUS_CHANNEL_RX)),
688 				5,
689 				TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT);
690 	if (ret) {
691 		dev_err(tdc2dev(tdc), "Timeout waiting for DMA burst completion!\n");
692 		tegra_dma_dump_chan_regs(tdc);
693 	}
694 
695 	return ret;
696 }
697 
698 static int tegra_dma_terminate_all(struct dma_chan *dc)
699 {
700 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
701 	unsigned long flags;
702 	LIST_HEAD(head);
703 	int err;
704 
705 	spin_lock_irqsave(&tdc->vc.lock, flags);
706 
707 	if (tdc->dma_desc) {
708 		err = tdc->tdma->chip_data->terminate(tdc);
709 		if (err) {
710 			spin_unlock_irqrestore(&tdc->vc.lock, flags);
711 			return err;
712 		}
713 
714 		tegra_dma_disable(tdc);
715 		tdc->dma_desc = NULL;
716 	}
717 
718 	tegra_dma_sid_free(tdc);
719 	vchan_get_all_descriptors(&tdc->vc, &head);
720 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
721 
722 	vchan_dma_desc_free_list(&tdc->vc, &head);
723 
724 	return 0;
725 }
726 
727 static int tegra_dma_get_residual(struct tegra_dma_channel *tdc)
728 {
729 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
730 	struct tegra_dma_sg_req *sg_req = dma_desc->sg_req;
731 	unsigned int bytes_xfer, residual;
732 	u32 wcount = 0, status;
733 
734 	wcount = tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT);
735 
736 	/*
737 	 * Set wcount = 0 if EOC bit is set. The transfer would have
738 	 * already completed and the CHAN_XFER_COUNT could have updated
739 	 * for the next transfer, specifically in case of cyclic transfers.
740 	 */
741 	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
742 	if (status & TEGRA_GPCDMA_STATUS_ISE_EOC)
743 		wcount = 0;
744 
745 	bytes_xfer = dma_desc->bytes_xfer +
746 		     sg_req[dma_desc->sg_idx].len - (wcount * 4);
747 
748 	residual = dma_desc->bytes_req - (bytes_xfer % dma_desc->bytes_req);
749 
750 	return residual;
751 }
752 
753 static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
754 					   dma_cookie_t cookie,
755 					   struct dma_tx_state *txstate)
756 {
757 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
758 	struct tegra_dma_desc *dma_desc;
759 	struct virt_dma_desc *vd;
760 	unsigned int residual;
761 	unsigned long flags;
762 	enum dma_status ret;
763 
764 	ret = dma_cookie_status(dc, cookie, txstate);
765 	if (ret == DMA_COMPLETE)
766 		return ret;
767 
768 	spin_lock_irqsave(&tdc->vc.lock, flags);
769 	vd = vchan_find_desc(&tdc->vc, cookie);
770 	if (vd) {
771 		dma_desc = vd_to_tegra_dma_desc(vd);
772 		residual = dma_desc->bytes_req;
773 		dma_set_residue(txstate, residual);
774 	} else if (tdc->dma_desc && tdc->dma_desc->vd.tx.cookie == cookie) {
775 		residual =  tegra_dma_get_residual(tdc);
776 		dma_set_residue(txstate, residual);
777 	} else {
778 		dev_err(tdc2dev(tdc), "cookie %d is not found\n", cookie);
779 	}
780 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
781 
782 	return ret;
783 }
784 
785 static inline int get_bus_width(struct tegra_dma_channel *tdc,
786 				enum dma_slave_buswidth slave_bw)
787 {
788 	switch (slave_bw) {
789 	case DMA_SLAVE_BUSWIDTH_1_BYTE:
790 		return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8;
791 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
792 		return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16;
793 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
794 		return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32;
795 	default:
796 		dev_err(tdc2dev(tdc), "given slave bus width is not supported\n");
797 		return -EINVAL;
798 	}
799 }
800 
801 static unsigned int get_burst_size(struct tegra_dma_channel *tdc,
802 				   u32 burst_size, enum dma_slave_buswidth slave_bw,
803 				   int len)
804 {
805 	unsigned int burst_mmio_width, burst_byte;
806 
807 	/*
808 	 * burst_size from client is in terms of the bus_width.
809 	 * convert that into words.
810 	 * If burst_size is not specified from client, then use
811 	 * len to calculate the optimum burst size
812 	 */
813 	burst_byte = burst_size ? burst_size * slave_bw : len;
814 	burst_mmio_width = burst_byte / 4;
815 
816 	if (burst_mmio_width < TEGRA_GPCDMA_MMIOSEQ_BURST_MIN)
817 		return 0;
818 
819 	burst_mmio_width = min(burst_mmio_width, TEGRA_GPCDMA_MMIOSEQ_BURST_MAX);
820 
821 	return TEGRA_GPCDMA_MMIOSEQ_BURST(burst_mmio_width);
822 }
823 
824 static int get_transfer_param(struct tegra_dma_channel *tdc,
825 			      enum dma_transfer_direction direction,
826 			      u32 *apb_addr,
827 			      u32 *mmio_seq,
828 			      u32 *csr,
829 			      unsigned int *burst_size,
830 			      enum dma_slave_buswidth *slave_bw)
831 {
832 	switch (direction) {
833 	case DMA_MEM_TO_DEV:
834 		*apb_addr = tdc->dma_sconfig.dst_addr;
835 		*mmio_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width);
836 		*burst_size = tdc->dma_sconfig.dst_maxburst;
837 		*slave_bw = tdc->dma_sconfig.dst_addr_width;
838 		*csr = TEGRA_GPCDMA_CSR_DMA_MEM2IO_FC;
839 		return 0;
840 	case DMA_DEV_TO_MEM:
841 		*apb_addr = tdc->dma_sconfig.src_addr;
842 		*mmio_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width);
843 		*burst_size = tdc->dma_sconfig.src_maxburst;
844 		*slave_bw = tdc->dma_sconfig.src_addr_width;
845 		*csr = TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC;
846 		return 0;
847 	default:
848 		dev_err(tdc2dev(tdc), "DMA direction is not supported\n");
849 	}
850 
851 	return -EINVAL;
852 }
853 
854 static struct dma_async_tx_descriptor *
855 tegra_dma_prep_dma_memset(struct dma_chan *dc, dma_addr_t dest, int value,
856 			  size_t len, unsigned long flags)
857 {
858 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
859 	unsigned int max_dma_count = tdc->tdma->chip_data->max_dma_count;
860 	struct tegra_dma_sg_req *sg_req;
861 	struct tegra_dma_desc *dma_desc;
862 	u32 csr, mc_seq;
863 
864 	if ((len & 3) || (dest & 3) || len > max_dma_count) {
865 		dev_err(tdc2dev(tdc),
866 			"DMA length/memory address is not supported\n");
867 		return NULL;
868 	}
869 
870 	/* Set DMA mode to fixed pattern */
871 	csr = TEGRA_GPCDMA_CSR_DMA_FIXED_PAT;
872 	/* Enable once or continuous mode */
873 	csr |= TEGRA_GPCDMA_CSR_ONCE;
874 	/* Enable IRQ mask */
875 	csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
876 	/* Enable the DMA interrupt */
877 	if (flags & DMA_PREP_INTERRUPT)
878 		csr |= TEGRA_GPCDMA_CSR_IE_EOC;
879 	/* Configure default priority weight for the channel */
880 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
881 
882 	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
883 	/* retain stream-id and clean rest */
884 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
885 
886 	/* Set the address wrapping */
887 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0,
888 						TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
889 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1,
890 						TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
891 
892 	/* Program outstanding MC requests */
893 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1);
894 	/* Set burst size */
895 	mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
896 
897 	dma_desc = kzalloc(struct_size(dma_desc, sg_req, 1), GFP_NOWAIT);
898 	if (!dma_desc)
899 		return NULL;
900 
901 	dma_desc->bytes_req = len;
902 	dma_desc->sg_count = 1;
903 	sg_req = dma_desc->sg_req;
904 
905 	sg_req[0].ch_regs.src_ptr = 0;
906 	sg_req[0].ch_regs.dst_ptr = dest;
907 	sg_req[0].ch_regs.high_addr_ptr =
908 			FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32));
909 	sg_req[0].ch_regs.fixed_pattern = value;
910 	/* Word count reg takes value as (N +1) words */
911 	sg_req[0].ch_regs.wcount = ((len - 4) >> 2);
912 	sg_req[0].ch_regs.csr = csr;
913 	sg_req[0].ch_regs.mmio_seq = 0;
914 	sg_req[0].ch_regs.mc_seq = mc_seq;
915 	sg_req[0].len = len;
916 
917 	dma_desc->cyclic = false;
918 	return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
919 }
920 
921 static struct dma_async_tx_descriptor *
922 tegra_dma_prep_dma_memcpy(struct dma_chan *dc, dma_addr_t dest,
923 			  dma_addr_t src, size_t len, unsigned long flags)
924 {
925 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
926 	struct tegra_dma_sg_req *sg_req;
927 	struct tegra_dma_desc *dma_desc;
928 	unsigned int max_dma_count;
929 	u32 csr, mc_seq;
930 
931 	max_dma_count = tdc->tdma->chip_data->max_dma_count;
932 	if ((len & 3) || (src & 3) || (dest & 3) || len > max_dma_count) {
933 		dev_err(tdc2dev(tdc),
934 			"DMA length/memory address is not supported\n");
935 		return NULL;
936 	}
937 
938 	/* Set DMA mode to memory to memory transfer */
939 	csr = TEGRA_GPCDMA_CSR_DMA_MEM2MEM;
940 	/* Enable once or continuous mode */
941 	csr |= TEGRA_GPCDMA_CSR_ONCE;
942 	/* Enable IRQ mask */
943 	csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
944 	/* Enable the DMA interrupt */
945 	if (flags & DMA_PREP_INTERRUPT)
946 		csr |= TEGRA_GPCDMA_CSR_IE_EOC;
947 	/* Configure default priority weight for the channel */
948 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
949 
950 	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
951 	/* retain stream-id and clean rest */
952 	mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK) |
953 		  (TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK);
954 
955 	/* Set the address wrapping */
956 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0,
957 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
958 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1,
959 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
960 
961 	/* Program outstanding MC requests */
962 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1);
963 	/* Set burst size */
964 	mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
965 
966 	dma_desc = kzalloc(struct_size(dma_desc, sg_req, 1), GFP_NOWAIT);
967 	if (!dma_desc)
968 		return NULL;
969 
970 	dma_desc->bytes_req = len;
971 	dma_desc->sg_count = 1;
972 	sg_req = dma_desc->sg_req;
973 
974 	sg_req[0].ch_regs.src_ptr = src;
975 	sg_req[0].ch_regs.dst_ptr = dest;
976 	sg_req[0].ch_regs.high_addr_ptr =
977 		FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (src >> 32));
978 	sg_req[0].ch_regs.high_addr_ptr |=
979 		FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32));
980 	/* Word count reg takes value as (N +1) words */
981 	sg_req[0].ch_regs.wcount = ((len - 4) >> 2);
982 	sg_req[0].ch_regs.csr = csr;
983 	sg_req[0].ch_regs.mmio_seq = 0;
984 	sg_req[0].ch_regs.mc_seq = mc_seq;
985 	sg_req[0].len = len;
986 
987 	dma_desc->cyclic = false;
988 	return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
989 }
990 
991 static struct dma_async_tx_descriptor *
992 tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
993 			unsigned int sg_len, enum dma_transfer_direction direction,
994 			unsigned long flags, void *context)
995 {
996 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
997 	unsigned int max_dma_count = tdc->tdma->chip_data->max_dma_count;
998 	enum dma_slave_buswidth slave_bw = DMA_SLAVE_BUSWIDTH_UNDEFINED;
999 	u32 csr, mc_seq, apb_ptr = 0, mmio_seq = 0;
1000 	struct tegra_dma_sg_req *sg_req;
1001 	struct tegra_dma_desc *dma_desc;
1002 	struct scatterlist *sg;
1003 	u32 burst_size;
1004 	unsigned int i;
1005 	int ret;
1006 
1007 	if (!tdc->config_init) {
1008 		dev_err(tdc2dev(tdc), "DMA channel is not configured\n");
1009 		return NULL;
1010 	}
1011 	if (sg_len < 1) {
1012 		dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len);
1013 		return NULL;
1014 	}
1015 
1016 	ret = tegra_dma_sid_reserve(tdc, direction);
1017 	if (ret)
1018 		return NULL;
1019 
1020 	ret = get_transfer_param(tdc, direction, &apb_ptr, &mmio_seq, &csr,
1021 				 &burst_size, &slave_bw);
1022 	if (ret < 0)
1023 		return NULL;
1024 
1025 	/* Enable once or continuous mode */
1026 	csr |= TEGRA_GPCDMA_CSR_ONCE;
1027 	/* Program the slave id in requestor select */
1028 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, tdc->slave_id);
1029 	/* Enable IRQ mask */
1030 	csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
1031 	/* Configure default priority weight for the channel*/
1032 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
1033 
1034 	/* Enable the DMA interrupt */
1035 	if (flags & DMA_PREP_INTERRUPT)
1036 		csr |= TEGRA_GPCDMA_CSR_IE_EOC;
1037 
1038 	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
1039 	/* retain stream-id and clean rest */
1040 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
1041 
1042 	/* Set the address wrapping on both MC and MMIO side */
1043 
1044 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0,
1045 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
1046 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1,
1047 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
1048 	mmio_seq |= FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD, 1);
1049 
1050 	/* Program 2 MC outstanding requests by default. */
1051 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1);
1052 
1053 	/* Setting MC burst size depending on MMIO burst size */
1054 	if (burst_size == 64)
1055 		mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
1056 	else
1057 		mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_2;
1058 
1059 	dma_desc = kzalloc(struct_size(dma_desc, sg_req, sg_len), GFP_NOWAIT);
1060 	if (!dma_desc)
1061 		return NULL;
1062 
1063 	dma_desc->sg_count = sg_len;
1064 	sg_req = dma_desc->sg_req;
1065 
1066 	/* Make transfer requests */
1067 	for_each_sg(sgl, sg, sg_len, i) {
1068 		u32 len;
1069 		dma_addr_t mem;
1070 
1071 		mem = sg_dma_address(sg);
1072 		len = sg_dma_len(sg);
1073 
1074 		if ((len & 3) || (mem & 3) || len > max_dma_count) {
1075 			dev_err(tdc2dev(tdc),
1076 				"DMA length/memory address is not supported\n");
1077 			kfree(dma_desc);
1078 			return NULL;
1079 		}
1080 
1081 		mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1082 		dma_desc->bytes_req += len;
1083 
1084 		if (direction == DMA_MEM_TO_DEV) {
1085 			sg_req[i].ch_regs.src_ptr = mem;
1086 			sg_req[i].ch_regs.dst_ptr = apb_ptr;
1087 			sg_req[i].ch_regs.high_addr_ptr =
1088 				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32));
1089 		} else if (direction == DMA_DEV_TO_MEM) {
1090 			sg_req[i].ch_regs.src_ptr = apb_ptr;
1091 			sg_req[i].ch_regs.dst_ptr = mem;
1092 			sg_req[i].ch_regs.high_addr_ptr =
1093 				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32));
1094 		}
1095 
1096 		/*
1097 		 * Word count register takes input in words. Writing a value
1098 		 * of N into word count register means a req of (N+1) words.
1099 		 */
1100 		sg_req[i].ch_regs.wcount = ((len - 4) >> 2);
1101 		sg_req[i].ch_regs.csr = csr;
1102 		sg_req[i].ch_regs.mmio_seq = mmio_seq;
1103 		sg_req[i].ch_regs.mc_seq = mc_seq;
1104 		sg_req[i].len = len;
1105 	}
1106 
1107 	dma_desc->cyclic = false;
1108 	return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
1109 }
1110 
1111 static struct dma_async_tx_descriptor *
1112 tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len,
1113 			  size_t period_len, enum dma_transfer_direction direction,
1114 			  unsigned long flags)
1115 {
1116 	enum dma_slave_buswidth slave_bw = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1117 	u32 csr, mc_seq, apb_ptr = 0, mmio_seq = 0, burst_size;
1118 	unsigned int max_dma_count, len, period_count, i;
1119 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1120 	struct tegra_dma_desc *dma_desc;
1121 	struct tegra_dma_sg_req *sg_req;
1122 	dma_addr_t mem = buf_addr;
1123 	int ret;
1124 
1125 	if (!buf_len || !period_len) {
1126 		dev_err(tdc2dev(tdc), "Invalid buffer/period len\n");
1127 		return NULL;
1128 	}
1129 
1130 	if (!tdc->config_init) {
1131 		dev_err(tdc2dev(tdc), "DMA slave is not configured\n");
1132 		return NULL;
1133 	}
1134 
1135 	ret = tegra_dma_sid_reserve(tdc, direction);
1136 	if (ret)
1137 		return NULL;
1138 
1139 	/*
1140 	 * We only support cycle transfer when buf_len is multiple of
1141 	 * period_len.
1142 	 */
1143 	if (buf_len % period_len) {
1144 		dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n");
1145 		return NULL;
1146 	}
1147 
1148 	len = period_len;
1149 	max_dma_count = tdc->tdma->chip_data->max_dma_count;
1150 	if ((len & 3) || (buf_addr & 3) || len > max_dma_count) {
1151 		dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n");
1152 		return NULL;
1153 	}
1154 
1155 	ret = get_transfer_param(tdc, direction, &apb_ptr, &mmio_seq, &csr,
1156 				 &burst_size, &slave_bw);
1157 	if (ret < 0)
1158 		return NULL;
1159 
1160 	/* Enable once or continuous mode */
1161 	csr &= ~TEGRA_GPCDMA_CSR_ONCE;
1162 	/* Program the slave id in requestor select */
1163 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, tdc->slave_id);
1164 	/* Enable IRQ mask */
1165 	csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
1166 	/* Configure default priority weight for the channel*/
1167 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
1168 
1169 	/* Enable the DMA interrupt */
1170 	if (flags & DMA_PREP_INTERRUPT)
1171 		csr |= TEGRA_GPCDMA_CSR_IE_EOC;
1172 
1173 	mmio_seq |= FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD, 1);
1174 
1175 	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
1176 	/* retain stream-id and clean rest */
1177 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
1178 
1179 	/* Set the address wrapping on both MC and MMIO side */
1180 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0,
1181 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
1182 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1,
1183 			     TEGRA_GPCDMA_MCSEQ_WRAP_NONE);
1184 
1185 	/* Program 2 MC outstanding requests by default. */
1186 	mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1);
1187 	/* Setting MC burst size depending on MMIO burst size */
1188 	if (burst_size == 64)
1189 		mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
1190 	else
1191 		mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_2;
1192 
1193 	period_count = buf_len / period_len;
1194 	dma_desc = kzalloc(struct_size(dma_desc, sg_req, period_count),
1195 			   GFP_NOWAIT);
1196 	if (!dma_desc)
1197 		return NULL;
1198 
1199 	dma_desc->bytes_req = buf_len;
1200 	dma_desc->sg_count = period_count;
1201 	sg_req = dma_desc->sg_req;
1202 
1203 	/* Split transfer equal to period size */
1204 	for (i = 0; i < period_count; i++) {
1205 		mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
1206 		if (direction == DMA_MEM_TO_DEV) {
1207 			sg_req[i].ch_regs.src_ptr = mem;
1208 			sg_req[i].ch_regs.dst_ptr = apb_ptr;
1209 			sg_req[i].ch_regs.high_addr_ptr =
1210 				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32));
1211 		} else if (direction == DMA_DEV_TO_MEM) {
1212 			sg_req[i].ch_regs.src_ptr = apb_ptr;
1213 			sg_req[i].ch_regs.dst_ptr = mem;
1214 			sg_req[i].ch_regs.high_addr_ptr =
1215 				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32));
1216 		}
1217 		/*
1218 		 * Word count register takes input in words. Writing a value
1219 		 * of N into word count register means a req of (N+1) words.
1220 		 */
1221 		sg_req[i].ch_regs.wcount = ((len - 4) >> 2);
1222 		sg_req[i].ch_regs.csr = csr;
1223 		sg_req[i].ch_regs.mmio_seq = mmio_seq;
1224 		sg_req[i].ch_regs.mc_seq = mc_seq;
1225 		sg_req[i].len = len;
1226 
1227 		mem += len;
1228 	}
1229 
1230 	dma_desc->cyclic = true;
1231 
1232 	return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
1233 }
1234 
1235 static int tegra_dma_alloc_chan_resources(struct dma_chan *dc)
1236 {
1237 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1238 	int ret;
1239 
1240 	ret = request_irq(tdc->irq, tegra_dma_isr, 0, tdc->name, tdc);
1241 	if (ret) {
1242 		dev_err(tdc2dev(tdc), "request_irq failed for %s\n", tdc->name);
1243 		return ret;
1244 	}
1245 
1246 	dma_cookie_init(&tdc->vc.chan);
1247 	tdc->config_init = false;
1248 	return 0;
1249 }
1250 
1251 static void tegra_dma_chan_synchronize(struct dma_chan *dc)
1252 {
1253 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1254 
1255 	synchronize_irq(tdc->irq);
1256 	vchan_synchronize(&tdc->vc);
1257 }
1258 
1259 static void tegra_dma_free_chan_resources(struct dma_chan *dc)
1260 {
1261 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
1262 
1263 	dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
1264 
1265 	tegra_dma_terminate_all(dc);
1266 	synchronize_irq(tdc->irq);
1267 
1268 	tasklet_kill(&tdc->vc.task);
1269 	tdc->config_init = false;
1270 	tdc->slave_id = -1;
1271 	tdc->sid_dir = DMA_TRANS_NONE;
1272 	free_irq(tdc->irq, tdc);
1273 
1274 	vchan_free_chan_resources(&tdc->vc);
1275 }
1276 
1277 static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
1278 					   struct of_dma *ofdma)
1279 {
1280 	struct tegra_dma *tdma = ofdma->of_dma_data;
1281 	struct tegra_dma_channel *tdc;
1282 	struct dma_chan *chan;
1283 
1284 	chan = dma_get_any_slave_channel(&tdma->dma_dev);
1285 	if (!chan)
1286 		return NULL;
1287 
1288 	tdc = to_tegra_dma_chan(chan);
1289 	tdc->slave_id = dma_spec->args[0];
1290 
1291 	return chan;
1292 }
1293 
1294 static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
1295 	.nr_channels = 32,
1296 	.channel_reg_size = SZ_64K,
1297 	.max_dma_count = SZ_1G,
1298 	.hw_support_pause = false,
1299 	.terminate = tegra_dma_stop_client,
1300 };
1301 
1302 static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
1303 	.nr_channels = 32,
1304 	.channel_reg_size = SZ_64K,
1305 	.max_dma_count = SZ_1G,
1306 	.hw_support_pause = true,
1307 	.terminate = tegra_dma_pause,
1308 };
1309 
1310 static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
1311 	.nr_channels = 32,
1312 	.channel_reg_size = SZ_64K,
1313 	.max_dma_count = SZ_1G,
1314 	.hw_support_pause = true,
1315 	.terminate = tegra_dma_pause_noerr,
1316 };
1317 
1318 static const struct of_device_id tegra_dma_of_match[] = {
1319 	{
1320 		.compatible = "nvidia,tegra186-gpcdma",
1321 		.data = &tegra186_dma_chip_data,
1322 	}, {
1323 		.compatible = "nvidia,tegra194-gpcdma",
1324 		.data = &tegra194_dma_chip_data,
1325 	}, {
1326 		.compatible = "nvidia,tegra234-gpcdma",
1327 		.data = &tegra234_dma_chip_data,
1328 	}, {
1329 	},
1330 };
1331 MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
1332 
1333 static int tegra_dma_program_sid(struct tegra_dma_channel *tdc, int stream_id)
1334 {
1335 	unsigned int reg_val =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
1336 
1337 	reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK);
1338 	reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK);
1339 
1340 	reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK, stream_id);
1341 	reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK, stream_id);
1342 
1343 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, reg_val);
1344 	return 0;
1345 }
1346 
1347 static int tegra_dma_probe(struct platform_device *pdev)
1348 {
1349 	const struct tegra_dma_chip_data *cdata = NULL;
1350 	struct iommu_fwspec *iommu_spec;
1351 	unsigned int stream_id, i;
1352 	struct tegra_dma *tdma;
1353 	int ret;
1354 
1355 	cdata = of_device_get_match_data(&pdev->dev);
1356 
1357 	tdma = devm_kzalloc(&pdev->dev,
1358 			    struct_size(tdma, channels, cdata->nr_channels),
1359 			    GFP_KERNEL);
1360 	if (!tdma)
1361 		return -ENOMEM;
1362 
1363 	tdma->dev = &pdev->dev;
1364 	tdma->chip_data = cdata;
1365 	platform_set_drvdata(pdev, tdma);
1366 
1367 	tdma->base_addr = devm_platform_ioremap_resource(pdev, 0);
1368 	if (IS_ERR(tdma->base_addr))
1369 		return PTR_ERR(tdma->base_addr);
1370 
1371 	tdma->rst = devm_reset_control_get_exclusive(&pdev->dev, "gpcdma");
1372 	if (IS_ERR(tdma->rst)) {
1373 		return dev_err_probe(&pdev->dev, PTR_ERR(tdma->rst),
1374 			      "Missing controller reset\n");
1375 	}
1376 	reset_control_reset(tdma->rst);
1377 
1378 	tdma->dma_dev.dev = &pdev->dev;
1379 
1380 	iommu_spec = dev_iommu_fwspec_get(&pdev->dev);
1381 	if (!iommu_spec) {
1382 		dev_err(&pdev->dev, "Missing iommu stream-id\n");
1383 		return -EINVAL;
1384 	}
1385 	stream_id = iommu_spec->ids[0] & 0xffff;
1386 
1387 	ret = device_property_read_u32(&pdev->dev, "dma-channel-mask",
1388 				       &tdma->chan_mask);
1389 	if (ret) {
1390 		dev_warn(&pdev->dev,
1391 			 "Missing dma-channel-mask property, using default channel mask %#x\n",
1392 			 TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK);
1393 		tdma->chan_mask = TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK;
1394 	}
1395 
1396 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
1397 	for (i = 0; i < cdata->nr_channels; i++) {
1398 		struct tegra_dma_channel *tdc = &tdma->channels[i];
1399 
1400 		/* Check for channel mask */
1401 		if (!(tdma->chan_mask & BIT(i)))
1402 			continue;
1403 
1404 		tdc->irq = platform_get_irq(pdev, i);
1405 		if (tdc->irq < 0)
1406 			return tdc->irq;
1407 
1408 		tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET +
1409 					i * cdata->channel_reg_size;
1410 		snprintf(tdc->name, sizeof(tdc->name), "gpcdma.%d", i);
1411 		tdc->tdma = tdma;
1412 		tdc->id = i;
1413 		tdc->slave_id = -1;
1414 
1415 		vchan_init(&tdc->vc, &tdma->dma_dev);
1416 		tdc->vc.desc_free = tegra_dma_desc_free;
1417 
1418 		/* program stream-id for this channel */
1419 		tegra_dma_program_sid(tdc, stream_id);
1420 		tdc->stream_id = stream_id;
1421 	}
1422 
1423 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
1424 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
1425 	dma_cap_set(DMA_MEMCPY, tdma->dma_dev.cap_mask);
1426 	dma_cap_set(DMA_MEMSET, tdma->dma_dev.cap_mask);
1427 	dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask);
1428 
1429 	/*
1430 	 * Only word aligned transfers are supported. Set the copy
1431 	 * alignment shift.
1432 	 */
1433 	tdma->dma_dev.copy_align = 2;
1434 	tdma->dma_dev.fill_align = 2;
1435 	tdma->dma_dev.device_alloc_chan_resources =
1436 					tegra_dma_alloc_chan_resources;
1437 	tdma->dma_dev.device_free_chan_resources =
1438 					tegra_dma_free_chan_resources;
1439 	tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg;
1440 	tdma->dma_dev.device_prep_dma_memcpy = tegra_dma_prep_dma_memcpy;
1441 	tdma->dma_dev.device_prep_dma_memset = tegra_dma_prep_dma_memset;
1442 	tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic;
1443 	tdma->dma_dev.device_config = tegra_dma_slave_config;
1444 	tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
1445 	tdma->dma_dev.device_tx_status = tegra_dma_tx_status;
1446 	tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending;
1447 	tdma->dma_dev.device_pause = tegra_dma_device_pause;
1448 	tdma->dma_dev.device_resume = tegra_dma_device_resume;
1449 	tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize;
1450 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1451 
1452 	ret = dma_async_device_register(&tdma->dma_dev);
1453 	if (ret < 0) {
1454 		dev_err_probe(&pdev->dev, ret,
1455 			      "GPC DMA driver registration failed\n");
1456 		return ret;
1457 	}
1458 
1459 	ret = of_dma_controller_register(pdev->dev.of_node,
1460 					 tegra_dma_of_xlate, tdma);
1461 	if (ret < 0) {
1462 		dev_err_probe(&pdev->dev, ret,
1463 			      "GPC DMA OF registration failed\n");
1464 
1465 		dma_async_device_unregister(&tdma->dma_dev);
1466 		return ret;
1467 	}
1468 
1469 	dev_info(&pdev->dev, "GPC DMA driver register %lu channels\n",
1470 		 hweight_long(tdma->chan_mask));
1471 
1472 	return 0;
1473 }
1474 
1475 static int tegra_dma_remove(struct platform_device *pdev)
1476 {
1477 	struct tegra_dma *tdma = platform_get_drvdata(pdev);
1478 
1479 	of_dma_controller_free(pdev->dev.of_node);
1480 	dma_async_device_unregister(&tdma->dma_dev);
1481 
1482 	return 0;
1483 }
1484 
1485 static int __maybe_unused tegra_dma_pm_suspend(struct device *dev)
1486 {
1487 	struct tegra_dma *tdma = dev_get_drvdata(dev);
1488 	unsigned int i;
1489 
1490 	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1491 		struct tegra_dma_channel *tdc = &tdma->channels[i];
1492 
1493 		if (!(tdma->chan_mask & BIT(i)))
1494 			continue;
1495 
1496 		if (tdc->dma_desc) {
1497 			dev_err(tdma->dev, "channel %u busy\n", i);
1498 			return -EBUSY;
1499 		}
1500 	}
1501 
1502 	return 0;
1503 }
1504 
1505 static int __maybe_unused tegra_dma_pm_resume(struct device *dev)
1506 {
1507 	struct tegra_dma *tdma = dev_get_drvdata(dev);
1508 	unsigned int i;
1509 
1510 	reset_control_reset(tdma->rst);
1511 
1512 	for (i = 0; i < tdma->chip_data->nr_channels; i++) {
1513 		struct tegra_dma_channel *tdc = &tdma->channels[i];
1514 
1515 		if (!(tdma->chan_mask & BIT(i)))
1516 			continue;
1517 
1518 		tegra_dma_program_sid(tdc, tdc->stream_id);
1519 	}
1520 
1521 	return 0;
1522 }
1523 
1524 static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
1525 	SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume)
1526 };
1527 
1528 static struct platform_driver tegra_dma_driver = {
1529 	.driver = {
1530 		.name	= "tegra-gpcdma",
1531 		.pm	= &tegra_dma_dev_pm_ops,
1532 		.of_match_table = tegra_dma_of_match,
1533 	},
1534 	.probe		= tegra_dma_probe,
1535 	.remove		= tegra_dma_remove,
1536 };
1537 
1538 module_platform_driver(tegra_dma_driver);
1539 
1540 MODULE_DESCRIPTION("NVIDIA Tegra GPC DMA Controller driver");
1541 MODULE_AUTHOR("Pavan Kunapuli <pkunapuli@nvidia.com>");
1542 MODULE_AUTHOR("Rajesh Gumasta <rgumasta@nvidia.com>");
1543 MODULE_LICENSE("GPL");
1544