xref: /openbmc/linux/drivers/dma/qcom/qcom_adm.c (revision 20e8ef5c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/device.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/dma/qcom_adm.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_dma.h>
21 #include <linux/platform_device.h>
22 #include <linux/reset.h>
23 #include <linux/scatterlist.h>
24 #include <linux/slab.h>
25 
26 #include "../dmaengine.h"
27 #include "../virt-dma.h"
28 
29 /* ADM registers - calculated from channel number and security domain */
30 #define ADM_CHAN_MULTI			0x4
31 #define ADM_CI_MULTI			0x4
32 #define ADM_CRCI_MULTI			0x4
33 #define ADM_EE_MULTI			0x800
34 #define ADM_CHAN_OFFS(chan)		(ADM_CHAN_MULTI * (chan))
35 #define ADM_EE_OFFS(ee)			(ADM_EE_MULTI * (ee))
36 #define ADM_CHAN_EE_OFFS(chan, ee)	(ADM_CHAN_OFFS(chan) + ADM_EE_OFFS(ee))
37 #define ADM_CHAN_OFFS(chan)		(ADM_CHAN_MULTI * (chan))
38 #define ADM_CI_OFFS(ci)			(ADM_CHAN_OFF(ci))
39 #define ADM_CH_CMD_PTR(chan, ee)	(ADM_CHAN_EE_OFFS(chan, ee))
40 #define ADM_CH_RSLT(chan, ee)		(0x40 + ADM_CHAN_EE_OFFS(chan, ee))
41 #define ADM_CH_FLUSH_STATE0(chan, ee)	(0x80 + ADM_CHAN_EE_OFFS(chan, ee))
42 #define ADM_CH_STATUS_SD(chan, ee)	(0x200 + ADM_CHAN_EE_OFFS(chan, ee))
43 #define ADM_CH_CONF(chan)		(0x240 + ADM_CHAN_OFFS(chan))
44 #define ADM_CH_RSLT_CONF(chan, ee)	(0x300 + ADM_CHAN_EE_OFFS(chan, ee))
45 #define ADM_SEC_DOMAIN_IRQ_STATUS(ee)	(0x380 + ADM_EE_OFFS(ee))
46 #define ADM_CI_CONF(ci)			(0x390 + (ci) * ADM_CI_MULTI)
47 #define ADM_GP_CTL			0x3d8
48 #define ADM_CRCI_CTL(crci, ee)		(0x400 + (crci) * ADM_CRCI_MULTI + \
49 						ADM_EE_OFFS(ee))
50 
51 /* channel status */
52 #define ADM_CH_STATUS_VALID		BIT(1)
53 
54 /* channel result */
55 #define ADM_CH_RSLT_VALID		BIT(31)
56 #define ADM_CH_RSLT_ERR			BIT(3)
57 #define ADM_CH_RSLT_FLUSH		BIT(2)
58 #define ADM_CH_RSLT_TPD			BIT(1)
59 
60 /* channel conf */
61 #define ADM_CH_CONF_SHADOW_EN		BIT(12)
62 #define ADM_CH_CONF_MPU_DISABLE		BIT(11)
63 #define ADM_CH_CONF_PERM_MPU_CONF	BIT(9)
64 #define ADM_CH_CONF_FORCE_RSLT_EN	BIT(7)
65 #define ADM_CH_CONF_SEC_DOMAIN(ee)	((((ee) & 0x3) << 4) | (((ee) & 0x4) << 11))
66 
67 /* channel result conf */
68 #define ADM_CH_RSLT_CONF_FLUSH_EN	BIT(1)
69 #define ADM_CH_RSLT_CONF_IRQ_EN		BIT(0)
70 
71 /* CRCI CTL */
72 #define ADM_CRCI_CTL_MUX_SEL		BIT(18)
73 #define ADM_CRCI_CTL_RST		BIT(17)
74 
75 /* CI configuration */
76 #define ADM_CI_RANGE_END(x)		((x) << 24)
77 #define ADM_CI_RANGE_START(x)		((x) << 16)
78 #define ADM_CI_BURST_4_WORDS		BIT(2)
79 #define ADM_CI_BURST_8_WORDS		BIT(3)
80 
81 /* GP CTL */
82 #define ADM_GP_CTL_LP_EN		BIT(12)
83 #define ADM_GP_CTL_LP_CNT(x)		((x) << 8)
84 
85 /* Command pointer list entry */
86 #define ADM_CPLE_LP			BIT(31)
87 #define ADM_CPLE_CMD_PTR_LIST		BIT(29)
88 
89 /* Command list entry */
90 #define ADM_CMD_LC			BIT(31)
91 #define ADM_CMD_DST_CRCI(n)		(((n) & 0xf) << 7)
92 #define ADM_CMD_SRC_CRCI(n)		(((n) & 0xf) << 3)
93 
94 #define ADM_CMD_TYPE_SINGLE		0x0
95 #define ADM_CMD_TYPE_BOX		0x3
96 
97 #define ADM_CRCI_MUX_SEL		BIT(4)
98 #define ADM_DESC_ALIGN			8
99 #define ADM_MAX_XFER			(SZ_64K - 1)
100 #define ADM_MAX_ROWS			(SZ_64K - 1)
101 #define ADM_MAX_CHANNELS		16
102 
103 struct adm_desc_hw_box {
104 	u32 cmd;
105 	u32 src_addr;
106 	u32 dst_addr;
107 	u32 row_len;
108 	u32 num_rows;
109 	u32 row_offset;
110 };
111 
112 struct adm_desc_hw_single {
113 	u32 cmd;
114 	u32 src_addr;
115 	u32 dst_addr;
116 	u32 len;
117 };
118 
119 struct adm_async_desc {
120 	struct virt_dma_desc vd;
121 	struct adm_device *adev;
122 
123 	size_t length;
124 	enum dma_transfer_direction dir;
125 	dma_addr_t dma_addr;
126 	size_t dma_len;
127 
128 	void *cpl;
129 	dma_addr_t cp_addr;
130 	u32 crci;
131 	u32 mux;
132 	u32 blk_size;
133 };
134 
135 struct adm_chan {
136 	struct virt_dma_chan vc;
137 	struct adm_device *adev;
138 
139 	/* parsed from DT */
140 	u32 id;			/* channel id */
141 
142 	struct adm_async_desc *curr_txd;
143 	struct dma_slave_config slave;
144 	u32 crci;
145 	u32 mux;
146 	struct list_head node;
147 
148 	int error;
149 	int initialized;
150 };
151 
152 static inline struct adm_chan *to_adm_chan(struct dma_chan *common)
153 {
154 	return container_of(common, struct adm_chan, vc.chan);
155 }
156 
157 struct adm_device {
158 	void __iomem *regs;
159 	struct device *dev;
160 	struct dma_device common;
161 	struct device_dma_parameters dma_parms;
162 	struct adm_chan *channels;
163 
164 	u32 ee;
165 
166 	struct clk *core_clk;
167 	struct clk *iface_clk;
168 
169 	struct reset_control *clk_reset;
170 	struct reset_control *c0_reset;
171 	struct reset_control *c1_reset;
172 	struct reset_control *c2_reset;
173 	int irq;
174 };
175 
176 /**
177  * adm_free_chan - Frees dma resources associated with the specific channel
178  *
179  * @chan: dma channel
180  *
181  * Free all allocated descriptors associated with this channel
182  */
183 static void adm_free_chan(struct dma_chan *chan)
184 {
185 	/* free all queued descriptors */
186 	vchan_free_chan_resources(to_virt_chan(chan));
187 }
188 
189 /**
190  * adm_get_blksize - Get block size from burst value
191  *
192  * @burst: Burst size of transaction
193  */
194 static int adm_get_blksize(unsigned int burst)
195 {
196 	int ret;
197 
198 	switch (burst) {
199 	case 16:
200 	case 32:
201 	case 64:
202 	case 128:
203 		ret = ffs(burst >> 4) - 1;
204 		break;
205 	case 192:
206 		ret = 4;
207 		break;
208 	case 256:
209 		ret = 5;
210 		break;
211 	default:
212 		ret = -EINVAL;
213 		break;
214 	}
215 
216 	return ret;
217 }
218 
219 /**
220  * adm_process_fc_descriptors - Process descriptors for flow controlled xfers
221  *
222  * @achan: ADM channel
223  * @desc: Descriptor memory pointer
224  * @sg: Scatterlist entry
225  * @crci: CRCI value
226  * @burst: Burst size of transaction
227  * @direction: DMA transfer direction
228  */
229 static void *adm_process_fc_descriptors(struct adm_chan *achan, void *desc,
230 					struct scatterlist *sg, u32 crci,
231 					u32 burst,
232 					enum dma_transfer_direction direction)
233 {
234 	struct adm_desc_hw_box *box_desc = NULL;
235 	struct adm_desc_hw_single *single_desc;
236 	u32 remainder = sg_dma_len(sg);
237 	u32 rows, row_offset, crci_cmd;
238 	u32 mem_addr = sg_dma_address(sg);
239 	u32 *incr_addr = &mem_addr;
240 	u32 *src, *dst;
241 
242 	if (direction == DMA_DEV_TO_MEM) {
243 		crci_cmd = ADM_CMD_SRC_CRCI(crci);
244 		row_offset = burst;
245 		src = &achan->slave.src_addr;
246 		dst = &mem_addr;
247 	} else {
248 		crci_cmd = ADM_CMD_DST_CRCI(crci);
249 		row_offset = burst << 16;
250 		src = &mem_addr;
251 		dst = &achan->slave.dst_addr;
252 	}
253 
254 	while (remainder >= burst) {
255 		box_desc = desc;
256 		box_desc->cmd = ADM_CMD_TYPE_BOX | crci_cmd;
257 		box_desc->row_offset = row_offset;
258 		box_desc->src_addr = *src;
259 		box_desc->dst_addr = *dst;
260 
261 		rows = remainder / burst;
262 		rows = min_t(u32, rows, ADM_MAX_ROWS);
263 		box_desc->num_rows = rows << 16 | rows;
264 		box_desc->row_len = burst << 16 | burst;
265 
266 		*incr_addr += burst * rows;
267 		remainder -= burst * rows;
268 		desc += sizeof(*box_desc);
269 	}
270 
271 	/* if leftover bytes, do one single descriptor */
272 	if (remainder) {
273 		single_desc = desc;
274 		single_desc->cmd = ADM_CMD_TYPE_SINGLE | crci_cmd;
275 		single_desc->len = remainder;
276 		single_desc->src_addr = *src;
277 		single_desc->dst_addr = *dst;
278 		desc += sizeof(*single_desc);
279 
280 		if (sg_is_last(sg))
281 			single_desc->cmd |= ADM_CMD_LC;
282 	} else {
283 		if (box_desc && sg_is_last(sg))
284 			box_desc->cmd |= ADM_CMD_LC;
285 	}
286 
287 	return desc;
288 }
289 
290 /**
291  * adm_process_non_fc_descriptors - Process descriptors for non-fc xfers
292  *
293  * @achan: ADM channel
294  * @desc: Descriptor memory pointer
295  * @sg: Scatterlist entry
296  * @direction: DMA transfer direction
297  */
298 static void *adm_process_non_fc_descriptors(struct adm_chan *achan, void *desc,
299 					    struct scatterlist *sg,
300 					    enum dma_transfer_direction direction)
301 {
302 	struct adm_desc_hw_single *single_desc;
303 	u32 remainder = sg_dma_len(sg);
304 	u32 mem_addr = sg_dma_address(sg);
305 	u32 *incr_addr = &mem_addr;
306 	u32 *src, *dst;
307 
308 	if (direction == DMA_DEV_TO_MEM) {
309 		src = &achan->slave.src_addr;
310 		dst = &mem_addr;
311 	} else {
312 		src = &mem_addr;
313 		dst = &achan->slave.dst_addr;
314 	}
315 
316 	do {
317 		single_desc = desc;
318 		single_desc->cmd = ADM_CMD_TYPE_SINGLE;
319 		single_desc->src_addr = *src;
320 		single_desc->dst_addr = *dst;
321 		single_desc->len = (remainder > ADM_MAX_XFER) ?
322 				ADM_MAX_XFER : remainder;
323 
324 		remainder -= single_desc->len;
325 		*incr_addr += single_desc->len;
326 		desc += sizeof(*single_desc);
327 	} while (remainder);
328 
329 	/* set last command if this is the end of the whole transaction */
330 	if (sg_is_last(sg))
331 		single_desc->cmd |= ADM_CMD_LC;
332 
333 	return desc;
334 }
335 
336 /**
337  * adm_prep_slave_sg - Prep slave sg transaction
338  *
339  * @chan: dma channel
340  * @sgl: scatter gather list
341  * @sg_len: length of sg
342  * @direction: DMA transfer direction
343  * @flags: DMA flags
344  * @context: transfer context (unused)
345  */
346 static struct dma_async_tx_descriptor *adm_prep_slave_sg(struct dma_chan *chan,
347 							 struct scatterlist *sgl,
348 							 unsigned int sg_len,
349 							 enum dma_transfer_direction direction,
350 							 unsigned long flags,
351 							 void *context)
352 {
353 	struct adm_chan *achan = to_adm_chan(chan);
354 	struct adm_device *adev = achan->adev;
355 	struct adm_async_desc *async_desc;
356 	struct scatterlist *sg;
357 	dma_addr_t cple_addr;
358 	u32 i, burst;
359 	u32 single_count = 0, box_count = 0, crci = 0;
360 	void *desc;
361 	u32 *cple;
362 	int blk_size = 0;
363 
364 	if (!is_slave_direction(direction)) {
365 		dev_err(adev->dev, "invalid dma direction\n");
366 		return NULL;
367 	}
368 
369 	/*
370 	 * get burst value from slave configuration
371 	 */
372 	burst = (direction == DMA_MEM_TO_DEV) ?
373 		achan->slave.dst_maxburst :
374 		achan->slave.src_maxburst;
375 
376 	/* if using flow control, validate burst and crci values */
377 	if (achan->slave.device_fc) {
378 		blk_size = adm_get_blksize(burst);
379 		if (blk_size < 0) {
380 			dev_err(adev->dev, "invalid burst value: %d\n",
381 				burst);
382 			return ERR_PTR(-EINVAL);
383 		}
384 
385 		crci = achan->crci & 0xf;
386 		if (!crci || achan->crci > 0x1f) {
387 			dev_err(adev->dev, "invalid crci value\n");
388 			return ERR_PTR(-EINVAL);
389 		}
390 	}
391 
392 	/* iterate through sgs and compute allocation size of structures */
393 	for_each_sg(sgl, sg, sg_len, i) {
394 		if (achan->slave.device_fc) {
395 			box_count += DIV_ROUND_UP(sg_dma_len(sg) / burst,
396 						  ADM_MAX_ROWS);
397 			if (sg_dma_len(sg) % burst)
398 				single_count++;
399 		} else {
400 			single_count += DIV_ROUND_UP(sg_dma_len(sg),
401 						     ADM_MAX_XFER);
402 		}
403 	}
404 
405 	async_desc = kzalloc(sizeof(*async_desc), GFP_NOWAIT);
406 	if (!async_desc)
407 		return ERR_PTR(-ENOMEM);
408 
409 	async_desc->mux = achan->mux ? ADM_CRCI_CTL_MUX_SEL : 0;
410 	async_desc->crci = crci;
411 	async_desc->blk_size = blk_size;
412 	async_desc->dma_len = single_count * sizeof(struct adm_desc_hw_single) +
413 				box_count * sizeof(struct adm_desc_hw_box) +
414 				sizeof(*cple) + 2 * ADM_DESC_ALIGN;
415 
416 	async_desc->cpl = kzalloc(async_desc->dma_len, GFP_NOWAIT);
417 	if (!async_desc->cpl)
418 		goto free;
419 
420 	async_desc->adev = adev;
421 
422 	/* both command list entry and descriptors must be 8 byte aligned */
423 	cple = PTR_ALIGN(async_desc->cpl, ADM_DESC_ALIGN);
424 	desc = PTR_ALIGN(cple + 1, ADM_DESC_ALIGN);
425 
426 	for_each_sg(sgl, sg, sg_len, i) {
427 		async_desc->length += sg_dma_len(sg);
428 
429 		if (achan->slave.device_fc)
430 			desc = adm_process_fc_descriptors(achan, desc, sg, crci,
431 							  burst, direction);
432 		else
433 			desc = adm_process_non_fc_descriptors(achan, desc, sg,
434 							      direction);
435 	}
436 
437 	async_desc->dma_addr = dma_map_single(adev->dev, async_desc->cpl,
438 					      async_desc->dma_len,
439 					      DMA_TO_DEVICE);
440 	if (dma_mapping_error(adev->dev, async_desc->dma_addr))
441 		goto free;
442 
443 	cple_addr = async_desc->dma_addr + ((void *)cple - async_desc->cpl);
444 
445 	/* init cmd list */
446 	dma_sync_single_for_cpu(adev->dev, cple_addr, sizeof(*cple),
447 				DMA_TO_DEVICE);
448 	*cple = ADM_CPLE_LP;
449 	*cple |= (async_desc->dma_addr + ADM_DESC_ALIGN) >> 3;
450 	dma_sync_single_for_device(adev->dev, cple_addr, sizeof(*cple),
451 				   DMA_TO_DEVICE);
452 
453 	return vchan_tx_prep(&achan->vc, &async_desc->vd, flags);
454 
455 free:
456 	kfree(async_desc);
457 	return ERR_PTR(-ENOMEM);
458 }
459 
460 /**
461  * adm_terminate_all - terminate all transactions on a channel
462  * @chan: dma channel
463  *
464  * Dequeues and frees all transactions, aborts current transaction
465  * No callbacks are done
466  *
467  */
468 static int adm_terminate_all(struct dma_chan *chan)
469 {
470 	struct adm_chan *achan = to_adm_chan(chan);
471 	struct adm_device *adev = achan->adev;
472 	unsigned long flags;
473 	LIST_HEAD(head);
474 
475 	spin_lock_irqsave(&achan->vc.lock, flags);
476 	vchan_get_all_descriptors(&achan->vc, &head);
477 
478 	/* send flush command to terminate current transaction */
479 	writel_relaxed(0x0,
480 		       adev->regs + ADM_CH_FLUSH_STATE0(achan->id, adev->ee));
481 
482 	spin_unlock_irqrestore(&achan->vc.lock, flags);
483 
484 	vchan_dma_desc_free_list(&achan->vc, &head);
485 
486 	return 0;
487 }
488 
489 static int adm_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg)
490 {
491 	struct adm_chan *achan = to_adm_chan(chan);
492 	struct qcom_adm_peripheral_config *config = cfg->peripheral_config;
493 	unsigned long flag;
494 
495 	spin_lock_irqsave(&achan->vc.lock, flag);
496 	memcpy(&achan->slave, cfg, sizeof(struct dma_slave_config));
497 	if (cfg->peripheral_size == sizeof(config))
498 		achan->crci = config->crci;
499 	spin_unlock_irqrestore(&achan->vc.lock, flag);
500 
501 	return 0;
502 }
503 
504 /**
505  * adm_start_dma - start next transaction
506  * @achan: ADM dma channel
507  */
508 static void adm_start_dma(struct adm_chan *achan)
509 {
510 	struct virt_dma_desc *vd = vchan_next_desc(&achan->vc);
511 	struct adm_device *adev = achan->adev;
512 	struct adm_async_desc *async_desc;
513 
514 	lockdep_assert_held(&achan->vc.lock);
515 
516 	if (!vd)
517 		return;
518 
519 	list_del(&vd->node);
520 
521 	/* write next command list out to the CMD FIFO */
522 	async_desc = container_of(vd, struct adm_async_desc, vd);
523 	achan->curr_txd = async_desc;
524 
525 	/* reset channel error */
526 	achan->error = 0;
527 
528 	if (!achan->initialized) {
529 		/* enable interrupts */
530 		writel(ADM_CH_CONF_SHADOW_EN |
531 		       ADM_CH_CONF_PERM_MPU_CONF |
532 		       ADM_CH_CONF_MPU_DISABLE |
533 		       ADM_CH_CONF_SEC_DOMAIN(adev->ee),
534 		       adev->regs + ADM_CH_CONF(achan->id));
535 
536 		writel(ADM_CH_RSLT_CONF_IRQ_EN | ADM_CH_RSLT_CONF_FLUSH_EN,
537 		       adev->regs + ADM_CH_RSLT_CONF(achan->id, adev->ee));
538 
539 		achan->initialized = 1;
540 	}
541 
542 	/* set the crci block size if this transaction requires CRCI */
543 	if (async_desc->crci) {
544 		writel(async_desc->mux | async_desc->blk_size,
545 		       adev->regs + ADM_CRCI_CTL(async_desc->crci, adev->ee));
546 	}
547 
548 	/* make sure IRQ enable doesn't get reordered */
549 	wmb();
550 
551 	/* write next command list out to the CMD FIFO */
552 	writel(ALIGN(async_desc->dma_addr, ADM_DESC_ALIGN) >> 3,
553 	       adev->regs + ADM_CH_CMD_PTR(achan->id, adev->ee));
554 }
555 
556 /**
557  * adm_dma_irq - irq handler for ADM controller
558  * @irq: IRQ of interrupt
559  * @data: callback data
560  *
561  * IRQ handler for the bam controller
562  */
563 static irqreturn_t adm_dma_irq(int irq, void *data)
564 {
565 	struct adm_device *adev = data;
566 	u32 srcs, i;
567 	struct adm_async_desc *async_desc;
568 	unsigned long flags;
569 
570 	srcs = readl_relaxed(adev->regs +
571 			ADM_SEC_DOMAIN_IRQ_STATUS(adev->ee));
572 
573 	for (i = 0; i < ADM_MAX_CHANNELS; i++) {
574 		struct adm_chan *achan = &adev->channels[i];
575 		u32 status, result;
576 
577 		if (srcs & BIT(i)) {
578 			status = readl_relaxed(adev->regs +
579 					       ADM_CH_STATUS_SD(i, adev->ee));
580 
581 			/* if no result present, skip */
582 			if (!(status & ADM_CH_STATUS_VALID))
583 				continue;
584 
585 			result = readl_relaxed(adev->regs +
586 				ADM_CH_RSLT(i, adev->ee));
587 
588 			/* no valid results, skip */
589 			if (!(result & ADM_CH_RSLT_VALID))
590 				continue;
591 
592 			/* flag error if transaction was flushed or failed */
593 			if (result & (ADM_CH_RSLT_ERR | ADM_CH_RSLT_FLUSH))
594 				achan->error = 1;
595 
596 			spin_lock_irqsave(&achan->vc.lock, flags);
597 			async_desc = achan->curr_txd;
598 
599 			achan->curr_txd = NULL;
600 
601 			if (async_desc) {
602 				vchan_cookie_complete(&async_desc->vd);
603 
604 				/* kick off next DMA */
605 				adm_start_dma(achan);
606 			}
607 
608 			spin_unlock_irqrestore(&achan->vc.lock, flags);
609 		}
610 	}
611 
612 	return IRQ_HANDLED;
613 }
614 
615 /**
616  * adm_tx_status - returns status of transaction
617  * @chan: dma channel
618  * @cookie: transaction cookie
619  * @txstate: DMA transaction state
620  *
621  * Return status of dma transaction
622  */
623 static enum dma_status adm_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
624 				     struct dma_tx_state *txstate)
625 {
626 	struct adm_chan *achan = to_adm_chan(chan);
627 	struct virt_dma_desc *vd;
628 	enum dma_status ret;
629 	unsigned long flags;
630 	size_t residue = 0;
631 
632 	ret = dma_cookie_status(chan, cookie, txstate);
633 	if (ret == DMA_COMPLETE || !txstate)
634 		return ret;
635 
636 	spin_lock_irqsave(&achan->vc.lock, flags);
637 
638 	vd = vchan_find_desc(&achan->vc, cookie);
639 	if (vd)
640 		residue = container_of(vd, struct adm_async_desc, vd)->length;
641 
642 	spin_unlock_irqrestore(&achan->vc.lock, flags);
643 
644 	/*
645 	 * residue is either the full length if it is in the issued list, or 0
646 	 * if it is in progress.  We have no reliable way of determining
647 	 * anything inbetween
648 	 */
649 	dma_set_residue(txstate, residue);
650 
651 	if (achan->error)
652 		return DMA_ERROR;
653 
654 	return ret;
655 }
656 
657 /**
658  * adm_issue_pending - starts pending transactions
659  * @chan: dma channel
660  *
661  * Issues all pending transactions and starts DMA
662  */
663 static void adm_issue_pending(struct dma_chan *chan)
664 {
665 	struct adm_chan *achan = to_adm_chan(chan);
666 	unsigned long flags;
667 
668 	spin_lock_irqsave(&achan->vc.lock, flags);
669 
670 	if (vchan_issue_pending(&achan->vc) && !achan->curr_txd)
671 		adm_start_dma(achan);
672 	spin_unlock_irqrestore(&achan->vc.lock, flags);
673 }
674 
675 /**
676  * adm_dma_free_desc - free descriptor memory
677  * @vd: virtual descriptor
678  *
679  */
680 static void adm_dma_free_desc(struct virt_dma_desc *vd)
681 {
682 	struct adm_async_desc *async_desc = container_of(vd,
683 			struct adm_async_desc, vd);
684 
685 	dma_unmap_single(async_desc->adev->dev, async_desc->dma_addr,
686 			 async_desc->dma_len, DMA_TO_DEVICE);
687 	kfree(async_desc->cpl);
688 	kfree(async_desc);
689 }
690 
691 static void adm_channel_init(struct adm_device *adev, struct adm_chan *achan,
692 			     u32 index)
693 {
694 	achan->id = index;
695 	achan->adev = adev;
696 
697 	vchan_init(&achan->vc, &adev->common);
698 	achan->vc.desc_free = adm_dma_free_desc;
699 }
700 
701 /**
702  * adm_dma_xlate
703  * @dma_spec:	pointer to DMA specifier as found in the device tree
704  * @ofdma:	pointer to DMA controller data
705  *
706  * This can use either 1-cell or 2-cell formats, the first cell
707  * identifies the slave device, while the optional second cell
708  * contains the crci value.
709  *
710  * Returns pointer to appropriate dma channel on success or NULL on error.
711  */
712 static struct dma_chan *adm_dma_xlate(struct of_phandle_args *dma_spec,
713 			       struct of_dma *ofdma)
714 {
715 	struct dma_device *dev = ofdma->of_dma_data;
716 	struct dma_chan *chan, *candidate = NULL;
717 	struct adm_chan *achan;
718 
719 	if (!dev || dma_spec->args_count > 2)
720 		return NULL;
721 
722 	list_for_each_entry(chan, &dev->channels, device_node)
723 		if (chan->chan_id == dma_spec->args[0]) {
724 			candidate = chan;
725 			break;
726 		}
727 
728 	if (!candidate)
729 		return NULL;
730 
731 	achan = to_adm_chan(candidate);
732 	if (dma_spec->args_count == 2)
733 		achan->crci = dma_spec->args[1];
734 	else
735 		achan->crci = 0;
736 
737 	return dma_get_slave_channel(candidate);
738 }
739 
740 static int adm_dma_probe(struct platform_device *pdev)
741 {
742 	struct adm_device *adev;
743 	int ret;
744 	u32 i;
745 
746 	adev = devm_kzalloc(&pdev->dev, sizeof(*adev), GFP_KERNEL);
747 	if (!adev)
748 		return -ENOMEM;
749 
750 	adev->dev = &pdev->dev;
751 
752 	adev->regs = devm_platform_ioremap_resource(pdev, 0);
753 	if (IS_ERR(adev->regs))
754 		return PTR_ERR(adev->regs);
755 
756 	adev->irq = platform_get_irq(pdev, 0);
757 	if (adev->irq < 0)
758 		return adev->irq;
759 
760 	ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &adev->ee);
761 	if (ret) {
762 		dev_err(adev->dev, "Execution environment unspecified\n");
763 		return ret;
764 	}
765 
766 	adev->core_clk = devm_clk_get(adev->dev, "core");
767 	if (IS_ERR(adev->core_clk))
768 		return PTR_ERR(adev->core_clk);
769 
770 	adev->iface_clk = devm_clk_get(adev->dev, "iface");
771 	if (IS_ERR(adev->iface_clk))
772 		return PTR_ERR(adev->iface_clk);
773 
774 	adev->clk_reset = devm_reset_control_get_exclusive(&pdev->dev, "clk");
775 	if (IS_ERR(adev->clk_reset)) {
776 		dev_err(adev->dev, "failed to get ADM0 reset\n");
777 		return PTR_ERR(adev->clk_reset);
778 	}
779 
780 	adev->c0_reset = devm_reset_control_get_exclusive(&pdev->dev, "c0");
781 	if (IS_ERR(adev->c0_reset)) {
782 		dev_err(adev->dev, "failed to get ADM0 C0 reset\n");
783 		return PTR_ERR(adev->c0_reset);
784 	}
785 
786 	adev->c1_reset = devm_reset_control_get_exclusive(&pdev->dev, "c1");
787 	if (IS_ERR(adev->c1_reset)) {
788 		dev_err(adev->dev, "failed to get ADM0 C1 reset\n");
789 		return PTR_ERR(adev->c1_reset);
790 	}
791 
792 	adev->c2_reset = devm_reset_control_get_exclusive(&pdev->dev, "c2");
793 	if (IS_ERR(adev->c2_reset)) {
794 		dev_err(adev->dev, "failed to get ADM0 C2 reset\n");
795 		return PTR_ERR(adev->c2_reset);
796 	}
797 
798 	ret = clk_prepare_enable(adev->core_clk);
799 	if (ret) {
800 		dev_err(adev->dev, "failed to prepare/enable core clock\n");
801 		return ret;
802 	}
803 
804 	ret = clk_prepare_enable(adev->iface_clk);
805 	if (ret) {
806 		dev_err(adev->dev, "failed to prepare/enable iface clock\n");
807 		goto err_disable_core_clk;
808 	}
809 
810 	reset_control_assert(adev->clk_reset);
811 	reset_control_assert(adev->c0_reset);
812 	reset_control_assert(adev->c1_reset);
813 	reset_control_assert(adev->c2_reset);
814 
815 	udelay(2);
816 
817 	reset_control_deassert(adev->clk_reset);
818 	reset_control_deassert(adev->c0_reset);
819 	reset_control_deassert(adev->c1_reset);
820 	reset_control_deassert(adev->c2_reset);
821 
822 	adev->channels = devm_kcalloc(adev->dev, ADM_MAX_CHANNELS,
823 				      sizeof(*adev->channels), GFP_KERNEL);
824 
825 	if (!adev->channels) {
826 		ret = -ENOMEM;
827 		goto err_disable_clks;
828 	}
829 
830 	/* allocate and initialize channels */
831 	INIT_LIST_HEAD(&adev->common.channels);
832 
833 	for (i = 0; i < ADM_MAX_CHANNELS; i++)
834 		adm_channel_init(adev, &adev->channels[i], i);
835 
836 	/* reset CRCIs */
837 	for (i = 0; i < 16; i++)
838 		writel(ADM_CRCI_CTL_RST, adev->regs +
839 			ADM_CRCI_CTL(i, adev->ee));
840 
841 	/* configure client interfaces */
842 	writel(ADM_CI_RANGE_START(0x40) | ADM_CI_RANGE_END(0xb0) |
843 	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(0));
844 	writel(ADM_CI_RANGE_START(0x2a) | ADM_CI_RANGE_END(0x2c) |
845 	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(1));
846 	writel(ADM_CI_RANGE_START(0x12) | ADM_CI_RANGE_END(0x28) |
847 	       ADM_CI_BURST_8_WORDS, adev->regs + ADM_CI_CONF(2));
848 	writel(ADM_GP_CTL_LP_EN | ADM_GP_CTL_LP_CNT(0xf),
849 	       adev->regs + ADM_GP_CTL);
850 
851 	ret = devm_request_irq(adev->dev, adev->irq, adm_dma_irq,
852 			       0, "adm_dma", adev);
853 	if (ret)
854 		goto err_disable_clks;
855 
856 	platform_set_drvdata(pdev, adev);
857 
858 	adev->common.dev = adev->dev;
859 	adev->common.dev->dma_parms = &adev->dma_parms;
860 
861 	/* set capabilities */
862 	dma_cap_zero(adev->common.cap_mask);
863 	dma_cap_set(DMA_SLAVE, adev->common.cap_mask);
864 	dma_cap_set(DMA_PRIVATE, adev->common.cap_mask);
865 
866 	/* initialize dmaengine apis */
867 	adev->common.directions = BIT(DMA_DEV_TO_MEM | DMA_MEM_TO_DEV);
868 	adev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
869 	adev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
870 	adev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
871 	adev->common.device_free_chan_resources = adm_free_chan;
872 	adev->common.device_prep_slave_sg = adm_prep_slave_sg;
873 	adev->common.device_issue_pending = adm_issue_pending;
874 	adev->common.device_tx_status = adm_tx_status;
875 	adev->common.device_terminate_all = adm_terminate_all;
876 	adev->common.device_config = adm_slave_config;
877 
878 	ret = dma_async_device_register(&adev->common);
879 	if (ret) {
880 		dev_err(adev->dev, "failed to register dma async device\n");
881 		goto err_disable_clks;
882 	}
883 
884 	ret = of_dma_controller_register(pdev->dev.of_node, adm_dma_xlate,
885 					 &adev->common);
886 	if (ret)
887 		goto err_unregister_dma;
888 
889 	return 0;
890 
891 err_unregister_dma:
892 	dma_async_device_unregister(&adev->common);
893 err_disable_clks:
894 	clk_disable_unprepare(adev->iface_clk);
895 err_disable_core_clk:
896 	clk_disable_unprepare(adev->core_clk);
897 
898 	return ret;
899 }
900 
901 static int adm_dma_remove(struct platform_device *pdev)
902 {
903 	struct adm_device *adev = platform_get_drvdata(pdev);
904 	struct adm_chan *achan;
905 	u32 i;
906 
907 	of_dma_controller_free(pdev->dev.of_node);
908 	dma_async_device_unregister(&adev->common);
909 
910 	for (i = 0; i < ADM_MAX_CHANNELS; i++) {
911 		achan = &adev->channels[i];
912 
913 		/* mask IRQs for this channel/EE pair */
914 		writel(0, adev->regs + ADM_CH_RSLT_CONF(achan->id, adev->ee));
915 
916 		tasklet_kill(&adev->channels[i].vc.task);
917 		adm_terminate_all(&adev->channels[i].vc.chan);
918 	}
919 
920 	devm_free_irq(adev->dev, adev->irq, adev);
921 
922 	clk_disable_unprepare(adev->core_clk);
923 	clk_disable_unprepare(adev->iface_clk);
924 
925 	return 0;
926 }
927 
928 static const struct of_device_id adm_of_match[] = {
929 	{ .compatible = "qcom,adm", },
930 	{}
931 };
932 MODULE_DEVICE_TABLE(of, adm_of_match);
933 
934 static struct platform_driver adm_dma_driver = {
935 	.probe = adm_dma_probe,
936 	.remove = adm_dma_remove,
937 	.driver = {
938 		.name = "adm-dma-engine",
939 		.of_match_table = adm_of_match,
940 	},
941 };
942 
943 module_platform_driver(adm_dma_driver);
944 
945 MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
946 MODULE_DESCRIPTION("QCOM ADM DMA engine driver");
947 MODULE_LICENSE("GPL v2");
948