xref: /linux/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 // (C) 2017-2018 Synopsys, Inc. (www.synopsys.com)
3 
4 /*
5  * Synopsys DesignWare AXI DMA Controller driver.
6  *
7  * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
8  */
9 
10 #include <linux/bitops.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/dmaengine.h>
14 #include <linux/dmapool.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/err.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/iopoll.h>
20 #include <linux/io-64-nonatomic-lo-hi.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/of.h>
24 #include <linux/of_dma.h>
25 #include <linux/platform_device.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/property.h>
28 #include <linux/reset.h>
29 #include <linux/slab.h>
30 #include <linux/types.h>
31 
32 #include "dw-axi-dmac.h"
33 #include "../dmaengine.h"
34 #include "../virt-dma.h"
35 
36 /*
37  * The set of bus widths supported by the DMA controller. DW AXI DMAC supports
38  * master data bus width up to 512 bits (for both AXI master interfaces), but
39  * it depends on IP block configuration.
40  */
41 #define AXI_DMA_BUSWIDTHS		  \
42 	(DMA_SLAVE_BUSWIDTH_1_BYTE	| \
43 	DMA_SLAVE_BUSWIDTH_2_BYTES	| \
44 	DMA_SLAVE_BUSWIDTH_4_BYTES	| \
45 	DMA_SLAVE_BUSWIDTH_8_BYTES	| \
46 	DMA_SLAVE_BUSWIDTH_16_BYTES	| \
47 	DMA_SLAVE_BUSWIDTH_32_BYTES	| \
48 	DMA_SLAVE_BUSWIDTH_64_BYTES)
49 
50 #define AXI_DMA_FLAG_HAS_APB_REGS	BIT(0)
51 #define AXI_DMA_FLAG_HAS_RESETS		BIT(1)
52 #define AXI_DMA_FLAG_USE_CFG2		BIT(2)
53 
54 static inline void
55 axi_dma_iowrite32(struct axi_dma_chip *chip, u32 reg, u32 val)
56 {
57 	iowrite32(val, chip->regs + reg);
58 }
59 
60 static inline u32 axi_dma_ioread32(struct axi_dma_chip *chip, u32 reg)
61 {
62 	return ioread32(chip->regs + reg);
63 }
64 
65 static inline void
66 axi_dma_iowrite64(struct axi_dma_chip *chip, u32 reg, u64 val)
67 {
68 	iowrite64(val, chip->regs + reg);
69 }
70 
71 static inline u64 axi_dma_ioread64(struct axi_dma_chip *chip, u32 reg)
72 {
73 	return ioread64(chip->regs + reg);
74 }
75 
76 static inline void
77 axi_chan_iowrite32(struct axi_dma_chan *chan, u32 reg, u32 val)
78 {
79 	iowrite32(val, chan->chan_regs + reg);
80 }
81 
82 static inline u32 axi_chan_ioread32(struct axi_dma_chan *chan, u32 reg)
83 {
84 	return ioread32(chan->chan_regs + reg);
85 }
86 
87 static inline void
88 axi_chan_iowrite64(struct axi_dma_chan *chan, u32 reg, u64 val)
89 {
90 	/*
91 	 * We split one 64 bit write for two 32 bit write as some HW doesn't
92 	 * support 64 bit access.
93 	 */
94 	iowrite32(lower_32_bits(val), chan->chan_regs + reg);
95 	iowrite32(upper_32_bits(val), chan->chan_regs + reg + 4);
96 }
97 
98 static inline void axi_chan_config_write(struct axi_dma_chan *chan,
99 					 struct axi_dma_chan_config *config)
100 {
101 	u32 cfg_lo, cfg_hi;
102 
103 	cfg_lo = (config->dst_multblk_type << CH_CFG_L_DST_MULTBLK_TYPE_POS |
104 		  config->src_multblk_type << CH_CFG_L_SRC_MULTBLK_TYPE_POS);
105 	if (chan->chip->dw->hdata->reg_map_8_channels &&
106 	    !chan->chip->dw->hdata->use_cfg2) {
107 		cfg_hi = config->tt_fc << CH_CFG_H_TT_FC_POS |
108 			 config->hs_sel_src << CH_CFG_H_HS_SEL_SRC_POS |
109 			 config->hs_sel_dst << CH_CFG_H_HS_SEL_DST_POS |
110 			 config->src_per << CH_CFG_H_SRC_PER_POS |
111 			 config->dst_per << CH_CFG_H_DST_PER_POS |
112 			 config->prior << CH_CFG_H_PRIORITY_POS;
113 	} else {
114 		cfg_lo |= config->src_per << CH_CFG2_L_SRC_PER_POS |
115 			  config->dst_per << CH_CFG2_L_DST_PER_POS;
116 		cfg_hi = config->tt_fc << CH_CFG2_H_TT_FC_POS |
117 			 config->hs_sel_src << CH_CFG2_H_HS_SEL_SRC_POS |
118 			 config->hs_sel_dst << CH_CFG2_H_HS_SEL_DST_POS |
119 			 config->prior << CH_CFG2_H_PRIORITY_POS;
120 	}
121 	axi_chan_iowrite32(chan, CH_CFG_L, cfg_lo);
122 	axi_chan_iowrite32(chan, CH_CFG_H, cfg_hi);
123 }
124 
125 static inline void axi_dma_disable(struct axi_dma_chip *chip)
126 {
127 	u32 val;
128 
129 	val = axi_dma_ioread32(chip, DMAC_CFG);
130 	val &= ~DMAC_EN_MASK;
131 	axi_dma_iowrite32(chip, DMAC_CFG, val);
132 }
133 
134 static inline void axi_dma_enable(struct axi_dma_chip *chip)
135 {
136 	u32 val;
137 
138 	val = axi_dma_ioread32(chip, DMAC_CFG);
139 	val |= DMAC_EN_MASK;
140 	axi_dma_iowrite32(chip, DMAC_CFG, val);
141 }
142 
143 static inline void axi_dma_irq_disable(struct axi_dma_chip *chip)
144 {
145 	u32 val;
146 
147 	val = axi_dma_ioread32(chip, DMAC_CFG);
148 	val &= ~INT_EN_MASK;
149 	axi_dma_iowrite32(chip, DMAC_CFG, val);
150 }
151 
152 static inline void axi_dma_irq_enable(struct axi_dma_chip *chip)
153 {
154 	u32 val;
155 
156 	val = axi_dma_ioread32(chip, DMAC_CFG);
157 	val |= INT_EN_MASK;
158 	axi_dma_iowrite32(chip, DMAC_CFG, val);
159 }
160 
161 static inline void axi_chan_irq_disable(struct axi_dma_chan *chan, u32 irq_mask)
162 {
163 	u32 val;
164 
165 	if (likely(irq_mask == DWAXIDMAC_IRQ_ALL)) {
166 		axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, DWAXIDMAC_IRQ_NONE);
167 	} else {
168 		val = axi_chan_ioread32(chan, CH_INTSTATUS_ENA);
169 		val &= ~irq_mask;
170 		axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, val);
171 	}
172 }
173 
174 static inline void axi_chan_irq_set(struct axi_dma_chan *chan, u32 irq_mask)
175 {
176 	axi_chan_iowrite32(chan, CH_INTSTATUS_ENA, irq_mask);
177 }
178 
179 static inline void axi_chan_irq_sig_set(struct axi_dma_chan *chan, u32 irq_mask)
180 {
181 	axi_chan_iowrite32(chan, CH_INTSIGNAL_ENA, irq_mask);
182 }
183 
184 static inline void axi_chan_irq_clear(struct axi_dma_chan *chan, u32 irq_mask)
185 {
186 	axi_chan_iowrite32(chan, CH_INTCLEAR, irq_mask);
187 }
188 
189 static inline u32 axi_chan_irq_read(struct axi_dma_chan *chan)
190 {
191 	return axi_chan_ioread32(chan, CH_INTSTATUS);
192 }
193 
194 static inline void axi_chan_disable(struct axi_dma_chan *chan)
195 {
196 	u64 val;
197 
198 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
199 		val = axi_dma_ioread64(chan->chip, DMAC_CHEN);
200 		if (chan->id >= DMAC_CHAN_16) {
201 			val &= ~((u64)(BIT(chan->id) >> DMAC_CHAN_16)
202 				<< (DMAC_CHAN_EN_SHIFT + DMAC_CHAN_BLOCK_SHIFT));
203 			val |=   (u64)(BIT(chan->id) >> DMAC_CHAN_16)
204 				<< (DMAC_CHAN_EN2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT);
205 		} else {
206 			val &= ~(BIT(chan->id) << DMAC_CHAN_EN_SHIFT);
207 			val |=   BIT(chan->id) << DMAC_CHAN_EN2_WE_SHIFT;
208 		}
209 		axi_dma_iowrite64(chan->chip, DMAC_CHEN, val);
210 	} else {
211 		val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
212 		val &= ~(BIT(chan->id) << DMAC_CHAN_EN_SHIFT);
213 		if (chan->chip->dw->hdata->reg_map_8_channels)
214 			val |=   BIT(chan->id) << DMAC_CHAN_EN_WE_SHIFT;
215 		else
216 			val |=   BIT(chan->id) << DMAC_CHAN_EN2_WE_SHIFT;
217 		axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
218 	}
219 }
220 
221 static inline void axi_chan_enable(struct axi_dma_chan *chan)
222 {
223 	u64 val;
224 
225 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
226 		val = axi_dma_ioread64(chan->chip, DMAC_CHEN);
227 		if (chan->id >= DMAC_CHAN_16) {
228 			val |= (u64)(BIT(chan->id) >> DMAC_CHAN_16)
229 				<< (DMAC_CHAN_EN_SHIFT + DMAC_CHAN_BLOCK_SHIFT) |
230 				(u64)(BIT(chan->id) >> DMAC_CHAN_16)
231 				<< (DMAC_CHAN_EN2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT);
232 		} else {
233 			val |= BIT(chan->id) << DMAC_CHAN_EN_SHIFT |
234 			BIT(chan->id) << DMAC_CHAN_EN2_WE_SHIFT;
235 		}
236 		axi_dma_iowrite64(chan->chip, DMAC_CHEN, val);
237 	} else {
238 		val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
239 		if (chan->chip->dw->hdata->reg_map_8_channels) {
240 			val |= BIT(chan->id) << DMAC_CHAN_EN_SHIFT |
241 			BIT(chan->id) << DMAC_CHAN_EN_WE_SHIFT;
242 		} else {
243 			val |= BIT(chan->id) << DMAC_CHAN_EN_SHIFT |
244 				BIT(chan->id) << DMAC_CHAN_EN2_WE_SHIFT;
245 		}
246 		axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
247 	}
248 }
249 
250 static inline bool axi_chan_is_hw_enable(struct axi_dma_chan *chan)
251 {
252 	u64 val;
253 
254 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16)
255 		val = axi_dma_ioread64(chan->chip, DMAC_CHEN);
256 	else
257 		val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
258 
259 	if (chan->id >= DMAC_CHAN_16)
260 		return !!(val & ((u64)(BIT(chan->id) >> DMAC_CHAN_16) << DMAC_CHAN_BLOCK_SHIFT));
261 	else
262 		return !!(val & (BIT(chan->id) << DMAC_CHAN_EN_SHIFT));
263 }
264 
265 static void axi_dma_hw_init(struct axi_dma_chip *chip)
266 {
267 	int ret;
268 	u32 i;
269 
270 	for (i = 0; i < chip->dw->hdata->nr_channels; i++) {
271 		axi_chan_irq_disable(&chip->dw->chan[i], DWAXIDMAC_IRQ_ALL);
272 		axi_chan_disable(&chip->dw->chan[i]);
273 	}
274 	ret = dma_set_mask_and_coherent(chip->dev, DMA_BIT_MASK(64));
275 	if (ret)
276 		dev_warn(chip->dev, "Unable to set coherent mask\n");
277 }
278 
279 static u32 axi_chan_get_xfer_width(struct axi_dma_chan *chan, dma_addr_t src,
280 				   dma_addr_t dst, size_t len)
281 {
282 	u32 max_width = chan->chip->dw->hdata->m_data_width;
283 
284 	return __ffs(src | dst | len | BIT(max_width));
285 }
286 
287 static inline const char *axi_chan_name(struct axi_dma_chan *chan)
288 {
289 	return dma_chan_name(&chan->vc.chan);
290 }
291 
292 static struct axi_dma_desc *axi_desc_alloc(u32 num)
293 {
294 	struct axi_dma_desc *desc;
295 
296 	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
297 	if (!desc)
298 		return NULL;
299 
300 	desc->hw_desc = kcalloc(num, sizeof(*desc->hw_desc), GFP_NOWAIT);
301 	if (!desc->hw_desc) {
302 		kfree(desc);
303 		return NULL;
304 	}
305 	desc->nr_hw_descs = num;
306 
307 	return desc;
308 }
309 
310 static struct axi_dma_lli *axi_desc_get(struct axi_dma_chan *chan,
311 					dma_addr_t *addr)
312 {
313 	struct axi_dma_lli *lli;
314 	dma_addr_t phys;
315 
316 	lli = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
317 	if (unlikely(!lli)) {
318 		dev_err(chan2dev(chan), "%s: not enough descriptors available\n",
319 			axi_chan_name(chan));
320 		return NULL;
321 	}
322 
323 	atomic_inc(&chan->descs_allocated);
324 	*addr = phys;
325 
326 	return lli;
327 }
328 
329 static void axi_desc_put(struct axi_dma_desc *desc)
330 {
331 	struct axi_dma_chan *chan = desc->chan;
332 	int count = desc->nr_hw_descs;
333 	struct axi_dma_hw_desc *hw_desc;
334 	int descs_put;
335 
336 	for (descs_put = 0; descs_put < count; descs_put++) {
337 		hw_desc = &desc->hw_desc[descs_put];
338 		dma_pool_free(chan->desc_pool, hw_desc->lli, hw_desc->llp);
339 	}
340 
341 	kfree(desc->hw_desc);
342 	kfree(desc);
343 	atomic_sub(descs_put, &chan->descs_allocated);
344 	dev_vdbg(chan2dev(chan), "%s: %d descs put, %d still allocated\n",
345 		axi_chan_name(chan), descs_put,
346 		atomic_read(&chan->descs_allocated));
347 }
348 
349 static void vchan_desc_put(struct virt_dma_desc *vdesc)
350 {
351 	axi_desc_put(vd_to_axi_desc(vdesc));
352 }
353 
354 static enum dma_status
355 dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
356 		  struct dma_tx_state *txstate)
357 {
358 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
359 	struct virt_dma_desc *vdesc;
360 	enum dma_status status;
361 	u32 completed_length;
362 	unsigned long flags;
363 	u32 completed_blocks;
364 	size_t bytes = 0;
365 	u32 length;
366 	u32 len;
367 
368 	status = dma_cookie_status(dchan, cookie, txstate);
369 	if (status == DMA_COMPLETE || !txstate)
370 		return status;
371 
372 	spin_lock_irqsave(&chan->vc.lock, flags);
373 
374 	vdesc = vchan_find_desc(&chan->vc, cookie);
375 	if (vdesc) {
376 		length = vd_to_axi_desc(vdesc)->length;
377 		completed_blocks = vd_to_axi_desc(vdesc)->completed_blocks;
378 		len = vd_to_axi_desc(vdesc)->hw_desc[0].len;
379 		completed_length = completed_blocks * len;
380 		bytes = length - completed_length;
381 	}
382 
383 	spin_unlock_irqrestore(&chan->vc.lock, flags);
384 	dma_set_residue(txstate, bytes);
385 
386 	return status;
387 }
388 
389 static void write_desc_llp(struct axi_dma_hw_desc *desc, dma_addr_t adr)
390 {
391 	desc->lli->llp = cpu_to_le64(adr);
392 }
393 
394 static void write_chan_llp(struct axi_dma_chan *chan, dma_addr_t adr)
395 {
396 	axi_chan_iowrite64(chan, CH_LLP, adr);
397 }
398 
399 static void dw_axi_dma_set_byte_halfword(struct axi_dma_chan *chan, bool set)
400 {
401 	u32 offset = DMAC_APB_BYTE_WR_CH_EN;
402 	u32 reg_width, val;
403 
404 	if (!chan->chip->apb_regs) {
405 		dev_dbg(chan->chip->dev, "apb_regs not initialized\n");
406 		return;
407 	}
408 
409 	reg_width = __ffs(chan->config.dst_addr_width);
410 	if (reg_width == DWAXIDMAC_TRANS_WIDTH_16)
411 		offset = DMAC_APB_HALFWORD_WR_CH_EN;
412 
413 	val = ioread32(chan->chip->apb_regs + offset);
414 
415 	if (set)
416 		val |= BIT(chan->id);
417 	else
418 		val &= ~BIT(chan->id);
419 
420 	iowrite32(val, chan->chip->apb_regs + offset);
421 }
422 /* Called in chan locked context */
423 static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
424 				      struct axi_dma_desc *first)
425 {
426 	u32 priority = chan->chip->dw->hdata->priority[chan->id];
427 	struct axi_dma_chan_config config = {};
428 	u32 irq_mask;
429 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
430 
431 	if (unlikely(axi_chan_is_hw_enable(chan))) {
432 		dev_err(chan2dev(chan), "%s is non-idle!\n",
433 			axi_chan_name(chan));
434 
435 		return;
436 	}
437 
438 	axi_dma_enable(chan->chip);
439 
440 	config.dst_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
441 	config.src_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
442 	config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
443 	config.prior = priority;
444 	config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
445 	config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
446 	switch (chan->direction) {
447 	case DMA_MEM_TO_DEV:
448 		dw_axi_dma_set_byte_halfword(chan, true);
449 		config.tt_fc = chan->config.device_fc ?
450 				DWAXIDMAC_TT_FC_MEM_TO_PER_DST :
451 				DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC;
452 		if (chan->chip->apb_regs)
453 			config.dst_per = chan->id;
454 		else
455 			config.dst_per = chan->hw_handshake_num;
456 		break;
457 	case DMA_DEV_TO_MEM:
458 		config.tt_fc = chan->config.device_fc ?
459 				DWAXIDMAC_TT_FC_PER_TO_MEM_SRC :
460 				DWAXIDMAC_TT_FC_PER_TO_MEM_DMAC;
461 		if (chan->chip->apb_regs)
462 			config.src_per = chan->id;
463 		else
464 			config.src_per = chan->hw_handshake_num;
465 		break;
466 	default:
467 		break;
468 	}
469 	axi_chan_config_write(chan, &config);
470 
471 	write_chan_llp(chan, first->hw_desc[0].llp | lms);
472 
473 	irq_mask = DWAXIDMAC_IRQ_DMA_TRF | DWAXIDMAC_IRQ_ALL_ERR;
474 	axi_chan_irq_sig_set(chan, irq_mask);
475 
476 	/* Generate 'suspend' status but don't generate interrupt */
477 	irq_mask |= DWAXIDMAC_IRQ_SUSPENDED;
478 	axi_chan_irq_set(chan, irq_mask);
479 
480 	axi_chan_enable(chan);
481 }
482 
483 static void axi_chan_start_first_queued(struct axi_dma_chan *chan)
484 {
485 	struct axi_dma_desc *desc;
486 	struct virt_dma_desc *vd;
487 
488 	vd = vchan_next_desc(&chan->vc);
489 	if (!vd)
490 		return;
491 
492 	desc = vd_to_axi_desc(vd);
493 	dev_vdbg(chan2dev(chan), "%s: started %u\n", axi_chan_name(chan),
494 		vd->tx.cookie);
495 	axi_chan_block_xfer_start(chan, desc);
496 }
497 
498 static void dma_chan_issue_pending(struct dma_chan *dchan)
499 {
500 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
501 	unsigned long flags;
502 
503 	spin_lock_irqsave(&chan->vc.lock, flags);
504 	if (vchan_issue_pending(&chan->vc))
505 		axi_chan_start_first_queued(chan);
506 	spin_unlock_irqrestore(&chan->vc.lock, flags);
507 }
508 
509 static void dw_axi_dma_synchronize(struct dma_chan *dchan)
510 {
511 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
512 
513 	vchan_synchronize(&chan->vc);
514 }
515 
516 static int dma_chan_alloc_chan_resources(struct dma_chan *dchan)
517 {
518 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
519 
520 	/* ASSERT: channel is idle */
521 	if (axi_chan_is_hw_enable(chan)) {
522 		dev_err(chan2dev(chan), "%s is non-idle!\n",
523 			axi_chan_name(chan));
524 		return -EBUSY;
525 	}
526 
527 	/* LLI address must be aligned to a 64-byte boundary */
528 	chan->desc_pool = dma_pool_create(dev_name(chan2dev(chan)),
529 					  chan->chip->dev,
530 					  sizeof(struct axi_dma_lli),
531 					  64, 0);
532 	if (!chan->desc_pool) {
533 		dev_err(chan2dev(chan), "No memory for descriptors\n");
534 		return -ENOMEM;
535 	}
536 	dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan));
537 
538 	pm_runtime_get(chan->chip->dev);
539 
540 	return 0;
541 }
542 
543 static void dma_chan_free_chan_resources(struct dma_chan *dchan)
544 {
545 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
546 
547 	/* ASSERT: channel is idle */
548 	if (axi_chan_is_hw_enable(chan))
549 		dev_err(dchan2dev(dchan), "%s is non-idle!\n",
550 			axi_chan_name(chan));
551 
552 	axi_chan_disable(chan);
553 	axi_chan_irq_disable(chan, DWAXIDMAC_IRQ_ALL);
554 
555 	vchan_free_chan_resources(&chan->vc);
556 
557 	dma_pool_destroy(chan->desc_pool);
558 	chan->desc_pool = NULL;
559 	dev_vdbg(dchan2dev(dchan),
560 		 "%s: free resources, descriptor still allocated: %u\n",
561 		 axi_chan_name(chan), atomic_read(&chan->descs_allocated));
562 
563 	pm_runtime_put(chan->chip->dev);
564 }
565 
566 static void dw_axi_dma_set_hw_channel(struct axi_dma_chan *chan, bool set)
567 {
568 	struct axi_dma_chip *chip = chan->chip;
569 	unsigned long reg_value, val;
570 
571 	if (!chip->apb_regs) {
572 		dev_err(chip->dev, "apb_regs not initialized\n");
573 		return;
574 	}
575 
576 	/*
577 	 * An unused DMA channel has a default value of 0x3F.
578 	 * Lock the DMA channel by assign a handshake number to the channel.
579 	 * Unlock the DMA channel by assign 0x3F to the channel.
580 	 */
581 	if (set)
582 		val = chan->hw_handshake_num;
583 	else
584 		val = UNUSED_CHANNEL;
585 
586 	reg_value = lo_hi_readq(chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
587 
588 	/* Channel is already allocated, set handshake as per channel ID */
589 	/* 64 bit write should handle for 8 channels */
590 
591 	reg_value &= ~(DMA_APB_HS_SEL_MASK <<
592 			(chan->id * DMA_APB_HS_SEL_BIT_SIZE));
593 	reg_value |= (val << (chan->id * DMA_APB_HS_SEL_BIT_SIZE));
594 	lo_hi_writeq(reg_value, chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
595 
596 	return;
597 }
598 
599 /*
600  * If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of the fetched LLI
601  * as 1, it understands that the current block is the final block in the
602  * transfer and completes the DMA transfer operation at the end of current
603  * block transfer.
604  */
605 static void set_desc_last(struct axi_dma_hw_desc *desc)
606 {
607 	u32 val;
608 
609 	val = le32_to_cpu(desc->lli->ctl_hi);
610 	val |= CH_CTL_H_LLI_LAST;
611 	desc->lli->ctl_hi = cpu_to_le32(val);
612 }
613 
614 static void write_desc_sar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
615 {
616 	desc->lli->sar = cpu_to_le64(adr);
617 }
618 
619 static void write_desc_dar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
620 {
621 	desc->lli->dar = cpu_to_le64(adr);
622 }
623 
624 static void set_desc_src_master(struct axi_dma_hw_desc *desc)
625 {
626 	u32 val;
627 
628 	/* Select AXI0 for source master */
629 	val = le32_to_cpu(desc->lli->ctl_lo);
630 	val &= ~CH_CTL_L_SRC_MAST;
631 	desc->lli->ctl_lo = cpu_to_le32(val);
632 }
633 
634 static void set_desc_dest_master(struct axi_dma_hw_desc *hw_desc,
635 				 struct axi_dma_desc *desc)
636 {
637 	u32 val;
638 
639 	/* Select AXI1 for source master if available */
640 	val = le32_to_cpu(hw_desc->lli->ctl_lo);
641 	if (desc->chan->chip->dw->hdata->nr_masters > 1)
642 		val |= CH_CTL_L_DST_MAST;
643 	else
644 		val &= ~CH_CTL_L_DST_MAST;
645 
646 	hw_desc->lli->ctl_lo = cpu_to_le32(val);
647 }
648 
649 static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
650 				  struct axi_dma_hw_desc *hw_desc,
651 				  dma_addr_t mem_addr, size_t len)
652 {
653 	unsigned int data_width = BIT(chan->chip->dw->hdata->m_data_width);
654 	unsigned int reg_width;
655 	unsigned int mem_width;
656 	dma_addr_t device_addr;
657 	size_t axi_block_ts;
658 	size_t block_ts;
659 	u32 ctllo, ctlhi;
660 	u32 burst_len;
661 
662 	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
663 
664 	mem_width = __ffs(data_width | mem_addr | len);
665 	if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
666 		mem_width = DWAXIDMAC_TRANS_WIDTH_32;
667 
668 	if (!IS_ALIGNED(mem_addr, 4)) {
669 		dev_err(chan->chip->dev, "invalid buffer alignment\n");
670 		return -EINVAL;
671 	}
672 
673 	switch (chan->direction) {
674 	case DMA_MEM_TO_DEV:
675 		reg_width = __ffs(chan->config.dst_addr_width);
676 		device_addr = chan->config.dst_addr;
677 		ctllo = reg_width << CH_CTL_L_DST_WIDTH_POS |
678 			mem_width << CH_CTL_L_SRC_WIDTH_POS |
679 			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_DST_INC_POS |
680 			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS;
681 		block_ts = len >> mem_width;
682 		break;
683 	case DMA_DEV_TO_MEM:
684 		reg_width = __ffs(chan->config.src_addr_width);
685 		device_addr = chan->config.src_addr;
686 		ctllo = reg_width << CH_CTL_L_SRC_WIDTH_POS |
687 			mem_width << CH_CTL_L_DST_WIDTH_POS |
688 			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
689 			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_SRC_INC_POS;
690 		block_ts = len >> reg_width;
691 		break;
692 	default:
693 		return -EINVAL;
694 	}
695 
696 	if (block_ts > axi_block_ts)
697 		return -EINVAL;
698 
699 	hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
700 	if (unlikely(!hw_desc->lli))
701 		return -ENOMEM;
702 
703 	ctlhi = CH_CTL_H_LLI_VALID;
704 
705 	if (chan->chip->dw->hdata->restrict_axi_burst_len) {
706 		burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
707 		ctlhi |= CH_CTL_H_ARLEN_EN | CH_CTL_H_AWLEN_EN |
708 			 burst_len << CH_CTL_H_ARLEN_POS |
709 			 burst_len << CH_CTL_H_AWLEN_POS;
710 	}
711 
712 	hw_desc->lli->ctl_hi = cpu_to_le32(ctlhi);
713 
714 	if (chan->direction == DMA_MEM_TO_DEV) {
715 		write_desc_sar(hw_desc, mem_addr);
716 		write_desc_dar(hw_desc, device_addr);
717 	} else {
718 		write_desc_sar(hw_desc, device_addr);
719 		write_desc_dar(hw_desc, mem_addr);
720 	}
721 
722 	hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
723 
724 	ctllo |= DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
725 		 DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS;
726 	hw_desc->lli->ctl_lo = cpu_to_le32(ctllo);
727 
728 	set_desc_src_master(hw_desc);
729 
730 	hw_desc->len = len;
731 	return 0;
732 }
733 
734 static size_t calculate_block_len(struct axi_dma_chan *chan,
735 				  dma_addr_t dma_addr, size_t buf_len,
736 				  enum dma_transfer_direction direction)
737 {
738 	u32 data_width, reg_width, mem_width;
739 	size_t axi_block_ts, block_len;
740 
741 	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
742 
743 	switch (direction) {
744 	case DMA_MEM_TO_DEV:
745 		data_width = BIT(chan->chip->dw->hdata->m_data_width);
746 		mem_width = __ffs(data_width | dma_addr | buf_len);
747 		if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
748 			mem_width = DWAXIDMAC_TRANS_WIDTH_32;
749 
750 		block_len = axi_block_ts << mem_width;
751 		break;
752 	case DMA_DEV_TO_MEM:
753 		reg_width = __ffs(chan->config.src_addr_width);
754 		block_len = axi_block_ts << reg_width;
755 		break;
756 	default:
757 		block_len = 0;
758 	}
759 
760 	return block_len;
761 }
762 
763 static struct dma_async_tx_descriptor *
764 dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
765 			    size_t buf_len, size_t period_len,
766 			    enum dma_transfer_direction direction,
767 			    unsigned long flags)
768 {
769 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
770 	struct axi_dma_hw_desc *hw_desc = NULL;
771 	struct axi_dma_desc *desc = NULL;
772 	dma_addr_t src_addr = dma_addr;
773 	u32 num_periods, num_segments;
774 	size_t axi_block_len;
775 	u32 total_segments;
776 	u32 segment_len;
777 	unsigned int i;
778 	int status;
779 	u64 llp = 0;
780 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
781 
782 	num_periods = buf_len / period_len;
783 
784 	axi_block_len = calculate_block_len(chan, dma_addr, buf_len, direction);
785 	if (axi_block_len == 0)
786 		return NULL;
787 
788 	num_segments = DIV_ROUND_UP(period_len, axi_block_len);
789 	segment_len = DIV_ROUND_UP(period_len, num_segments);
790 
791 	total_segments = num_periods * num_segments;
792 
793 	desc = axi_desc_alloc(total_segments);
794 	if (unlikely(!desc))
795 		goto err_desc_get;
796 
797 	chan->direction = direction;
798 	desc->chan = chan;
799 	chan->cyclic = true;
800 	desc->length = 0;
801 	desc->period_len = period_len;
802 
803 	for (i = 0; i < total_segments; i++) {
804 		hw_desc = &desc->hw_desc[i];
805 
806 		status = dw_axi_dma_set_hw_desc(chan, hw_desc, src_addr,
807 						segment_len);
808 		if (status < 0)
809 			goto err_desc_get;
810 
811 		desc->length += hw_desc->len;
812 		/* Set end-of-link to the linked descriptor, so that cyclic
813 		 * callback function can be triggered during interrupt.
814 		 */
815 		set_desc_last(hw_desc);
816 
817 		src_addr += segment_len;
818 	}
819 
820 	llp = desc->hw_desc[0].llp;
821 
822 	/* Managed transfer list */
823 	do {
824 		hw_desc = &desc->hw_desc[--total_segments];
825 		write_desc_llp(hw_desc, llp | lms);
826 		llp = hw_desc->llp;
827 	} while (total_segments);
828 
829 	dw_axi_dma_set_hw_channel(chan, true);
830 
831 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
832 
833 err_desc_get:
834 	if (desc)
835 		axi_desc_put(desc);
836 
837 	return NULL;
838 }
839 
840 static struct dma_async_tx_descriptor *
841 dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
842 			      unsigned int sg_len,
843 			      enum dma_transfer_direction direction,
844 			      unsigned long flags, void *context)
845 {
846 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
847 	struct axi_dma_hw_desc *hw_desc = NULL;
848 	struct axi_dma_desc *desc = NULL;
849 	u32 num_segments, segment_len;
850 	unsigned int loop = 0;
851 	struct scatterlist *sg;
852 	size_t axi_block_len;
853 	u32 len, num_sgs = 0;
854 	unsigned int i;
855 	dma_addr_t mem;
856 	int status;
857 	u64 llp = 0;
858 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
859 
860 	if (unlikely(!is_slave_direction(direction) || !sg_len))
861 		return NULL;
862 
863 	mem = sg_dma_address(sgl);
864 	len = sg_dma_len(sgl);
865 
866 	axi_block_len = calculate_block_len(chan, mem, len, direction);
867 	if (axi_block_len == 0)
868 		return NULL;
869 
870 	for_each_sg(sgl, sg, sg_len, i)
871 		num_sgs += DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
872 
873 	desc = axi_desc_alloc(num_sgs);
874 	if (unlikely(!desc))
875 		goto err_desc_get;
876 
877 	desc->chan = chan;
878 	desc->length = 0;
879 	chan->direction = direction;
880 
881 	for_each_sg(sgl, sg, sg_len, i) {
882 		mem = sg_dma_address(sg);
883 		len = sg_dma_len(sg);
884 		num_segments = DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
885 		segment_len = DIV_ROUND_UP(sg_dma_len(sg), num_segments);
886 
887 		do {
888 			hw_desc = &desc->hw_desc[loop++];
889 			status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, segment_len);
890 			if (status < 0)
891 				goto err_desc_get;
892 
893 			desc->length += hw_desc->len;
894 			len -= segment_len;
895 			mem += segment_len;
896 		} while (len >= segment_len);
897 	}
898 
899 	/* Set end-of-link to the last link descriptor of list */
900 	set_desc_last(&desc->hw_desc[num_sgs - 1]);
901 
902 	/* Managed transfer list */
903 	do {
904 		hw_desc = &desc->hw_desc[--num_sgs];
905 		write_desc_llp(hw_desc, llp | lms);
906 		llp = hw_desc->llp;
907 	} while (num_sgs);
908 
909 	dw_axi_dma_set_hw_channel(chan, true);
910 
911 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
912 
913 err_desc_get:
914 	if (desc)
915 		axi_desc_put(desc);
916 
917 	return NULL;
918 }
919 
920 static struct dma_async_tx_descriptor *
921 dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
922 			 dma_addr_t src_adr, size_t len, unsigned long flags)
923 {
924 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
925 	size_t block_ts, max_block_ts, xfer_len;
926 	struct axi_dma_hw_desc *hw_desc = NULL;
927 	struct axi_dma_desc *desc = NULL;
928 	u32 xfer_width, reg, num;
929 	u64 llp = 0;
930 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
931 
932 	dev_dbg(chan2dev(chan), "%s: memcpy: src: %pad dst: %pad length: %zd flags: %#lx",
933 		axi_chan_name(chan), &src_adr, &dst_adr, len, flags);
934 
935 	max_block_ts = chan->chip->dw->hdata->block_size[chan->id];
936 	xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, len);
937 	num = DIV_ROUND_UP(len, max_block_ts << xfer_width);
938 	desc = axi_desc_alloc(num);
939 	if (unlikely(!desc))
940 		goto err_desc_get;
941 
942 	desc->chan = chan;
943 	num = 0;
944 	desc->length = 0;
945 	while (len) {
946 		xfer_len = len;
947 
948 		hw_desc = &desc->hw_desc[num];
949 		/*
950 		 * Take care for the alignment.
951 		 * Actually source and destination widths can be different, but
952 		 * make them same to be simpler.
953 		 */
954 		xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, xfer_len);
955 
956 		/*
957 		 * block_ts indicates the total number of data of width
958 		 * to be transferred in a DMA block transfer.
959 		 * BLOCK_TS register should be set to block_ts - 1
960 		 */
961 		block_ts = xfer_len >> xfer_width;
962 		if (block_ts > max_block_ts) {
963 			block_ts = max_block_ts;
964 			xfer_len = max_block_ts << xfer_width;
965 		}
966 
967 		hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
968 		if (unlikely(!hw_desc->lli))
969 			goto err_desc_get;
970 
971 		write_desc_sar(hw_desc, src_adr);
972 		write_desc_dar(hw_desc, dst_adr);
973 		hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
974 
975 		reg = CH_CTL_H_LLI_VALID;
976 		if (chan->chip->dw->hdata->restrict_axi_burst_len) {
977 			u32 burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
978 
979 			reg |= (CH_CTL_H_ARLEN_EN |
980 				burst_len << CH_CTL_H_ARLEN_POS |
981 				CH_CTL_H_AWLEN_EN |
982 				burst_len << CH_CTL_H_AWLEN_POS);
983 		}
984 		hw_desc->lli->ctl_hi = cpu_to_le32(reg);
985 
986 		reg = (DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
987 		       DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS |
988 		       xfer_width << CH_CTL_L_DST_WIDTH_POS |
989 		       xfer_width << CH_CTL_L_SRC_WIDTH_POS |
990 		       DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
991 		       DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS);
992 		hw_desc->lli->ctl_lo = cpu_to_le32(reg);
993 
994 		set_desc_src_master(hw_desc);
995 		set_desc_dest_master(hw_desc, desc);
996 
997 		hw_desc->len = xfer_len;
998 		desc->length += hw_desc->len;
999 		/* update the length and addresses for the next loop cycle */
1000 		len -= xfer_len;
1001 		dst_adr += xfer_len;
1002 		src_adr += xfer_len;
1003 		num++;
1004 	}
1005 
1006 	/* Set end-of-link to the last link descriptor of list */
1007 	set_desc_last(&desc->hw_desc[num - 1]);
1008 	/* Managed transfer list */
1009 	do {
1010 		hw_desc = &desc->hw_desc[--num];
1011 		write_desc_llp(hw_desc, llp | lms);
1012 		llp = hw_desc->llp;
1013 	} while (num);
1014 
1015 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
1016 
1017 err_desc_get:
1018 	if (desc)
1019 		axi_desc_put(desc);
1020 	return NULL;
1021 }
1022 
1023 static int dw_axi_dma_chan_slave_config(struct dma_chan *dchan,
1024 					struct dma_slave_config *config)
1025 {
1026 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1027 
1028 	memcpy(&chan->config, config, sizeof(*config));
1029 
1030 	return 0;
1031 }
1032 
1033 static void axi_chan_dump_lli(struct axi_dma_chan *chan,
1034 			      struct axi_dma_hw_desc *desc)
1035 {
1036 	if (!desc->lli) {
1037 		dev_err(dchan2dev(&chan->vc.chan), "NULL LLI\n");
1038 		return;
1039 	}
1040 
1041 	dev_err(dchan2dev(&chan->vc.chan),
1042 		"SAR: 0x%llx DAR: 0x%llx LLP: 0x%llx BTS 0x%x CTL: 0x%x:%08x",
1043 		le64_to_cpu(desc->lli->sar),
1044 		le64_to_cpu(desc->lli->dar),
1045 		le64_to_cpu(desc->lli->llp),
1046 		le32_to_cpu(desc->lli->block_ts_lo),
1047 		le32_to_cpu(desc->lli->ctl_hi),
1048 		le32_to_cpu(desc->lli->ctl_lo));
1049 }
1050 
1051 static void axi_chan_list_dump_lli(struct axi_dma_chan *chan,
1052 				   struct axi_dma_desc *desc_head)
1053 {
1054 	int count = atomic_read(&chan->descs_allocated);
1055 	int i;
1056 
1057 	for (i = 0; i < count; i++)
1058 		axi_chan_dump_lli(chan, &desc_head->hw_desc[i]);
1059 }
1060 
1061 static noinline void axi_chan_handle_err(struct axi_dma_chan *chan, u32 status)
1062 {
1063 	struct virt_dma_desc *vd;
1064 	unsigned long flags;
1065 
1066 	spin_lock_irqsave(&chan->vc.lock, flags);
1067 
1068 	axi_chan_disable(chan);
1069 
1070 	/* The bad descriptor currently is in the head of vc list */
1071 	vd = vchan_next_desc(&chan->vc);
1072 	if (!vd) {
1073 		dev_err(chan2dev(chan), "BUG: %s, IRQ with no descriptors\n",
1074 			axi_chan_name(chan));
1075 		goto out;
1076 	}
1077 	/* Remove the completed descriptor from issued list */
1078 	list_del(&vd->node);
1079 
1080 	/* WARN about bad descriptor */
1081 	dev_err(chan2dev(chan),
1082 		"Bad descriptor submitted for %s, cookie: %d, irq: 0x%08x\n",
1083 		axi_chan_name(chan), vd->tx.cookie, status);
1084 	axi_chan_list_dump_lli(chan, vd_to_axi_desc(vd));
1085 
1086 	vchan_cookie_complete(vd);
1087 
1088 	/* Try to restart the controller */
1089 	axi_chan_start_first_queued(chan);
1090 
1091 out:
1092 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1093 }
1094 
1095 static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
1096 {
1097 	int count = atomic_read(&chan->descs_allocated);
1098 	struct axi_dma_hw_desc *hw_desc;
1099 	struct axi_dma_desc *desc;
1100 	struct virt_dma_desc *vd;
1101 	unsigned long flags;
1102 	u64 llp;
1103 	int i;
1104 
1105 	spin_lock_irqsave(&chan->vc.lock, flags);
1106 	if (unlikely(axi_chan_is_hw_enable(chan))) {
1107 		dev_err(chan2dev(chan), "BUG: %s caught DWAXIDMAC_IRQ_DMA_TRF, but channel not idle!\n",
1108 			axi_chan_name(chan));
1109 		axi_chan_disable(chan);
1110 	}
1111 
1112 	/* The completed descriptor currently is in the head of vc list */
1113 	vd = vchan_next_desc(&chan->vc);
1114 	if (!vd) {
1115 		dev_err(chan2dev(chan), "BUG: %s, IRQ with no descriptors\n",
1116 			axi_chan_name(chan));
1117 		goto out;
1118 	}
1119 
1120 	if (chan->cyclic) {
1121 		desc = vd_to_axi_desc(vd);
1122 		if (desc) {
1123 			llp = lo_hi_readq(chan->chan_regs + CH_LLP);
1124 			for (i = 0; i < count; i++) {
1125 				hw_desc = &desc->hw_desc[i];
1126 				if (hw_desc->llp == llp) {
1127 					axi_chan_irq_clear(chan, hw_desc->lli->status_lo);
1128 					hw_desc->lli->ctl_hi |= CH_CTL_H_LLI_VALID;
1129 					desc->completed_blocks = i;
1130 
1131 					if (((hw_desc->len * (i + 1)) % desc->period_len) == 0)
1132 						vchan_cyclic_callback(vd);
1133 					break;
1134 				}
1135 			}
1136 
1137 			axi_chan_enable(chan);
1138 		}
1139 	} else {
1140 		/* Remove the completed descriptor from issued list before completing */
1141 		list_del(&vd->node);
1142 		vchan_cookie_complete(vd);
1143 	}
1144 
1145 out:
1146 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1147 }
1148 
1149 static irqreturn_t dw_axi_dma_interrupt(int irq, void *dev_id)
1150 {
1151 	struct axi_dma_chip *chip = dev_id;
1152 	struct dw_axi_dma *dw = chip->dw;
1153 	struct axi_dma_chan *chan;
1154 
1155 	u32 status, i;
1156 
1157 	/* Disable DMAC interrupts. We'll enable them after processing channels */
1158 	axi_dma_irq_disable(chip);
1159 
1160 	/* Poll, clear and process every channel interrupt status */
1161 	for (i = 0; i < dw->hdata->nr_channels; i++) {
1162 		chan = &dw->chan[i];
1163 		status = axi_chan_irq_read(chan);
1164 		axi_chan_irq_clear(chan, status);
1165 
1166 		dev_vdbg(chip->dev, "%s %u IRQ status: 0x%08x\n",
1167 			axi_chan_name(chan), i, status);
1168 
1169 		if (status & DWAXIDMAC_IRQ_ALL_ERR)
1170 			axi_chan_handle_err(chan, status);
1171 		else if (status & DWAXIDMAC_IRQ_DMA_TRF)
1172 			axi_chan_block_xfer_complete(chan);
1173 	}
1174 
1175 	/* Re-enable interrupts */
1176 	axi_dma_irq_enable(chip);
1177 
1178 	return IRQ_HANDLED;
1179 }
1180 
1181 static int dma_chan_terminate_all(struct dma_chan *dchan)
1182 {
1183 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1184 	u32 chan_active = BIT(chan->id) << DMAC_CHAN_EN_SHIFT;
1185 	unsigned long flags;
1186 	u32 val;
1187 	int ret;
1188 	LIST_HEAD(head);
1189 
1190 	axi_chan_disable(chan);
1191 
1192 	ret = readl_poll_timeout_atomic(chan->chip->regs + DMAC_CHEN, val,
1193 					!(val & chan_active), 1000, 50000);
1194 	if (ret == -ETIMEDOUT)
1195 		dev_warn(dchan2dev(dchan),
1196 			 "%s failed to stop\n", axi_chan_name(chan));
1197 
1198 	if (chan->direction != DMA_MEM_TO_MEM)
1199 		dw_axi_dma_set_hw_channel(chan, false);
1200 	if (chan->direction == DMA_MEM_TO_DEV)
1201 		dw_axi_dma_set_byte_halfword(chan, false);
1202 
1203 	spin_lock_irqsave(&chan->vc.lock, flags);
1204 
1205 	vchan_get_all_descriptors(&chan->vc, &head);
1206 
1207 	chan->cyclic = false;
1208 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1209 
1210 	vchan_dma_desc_free_list(&chan->vc, &head);
1211 
1212 	dev_vdbg(dchan2dev(dchan), "terminated: %s\n", axi_chan_name(chan));
1213 
1214 	return 0;
1215 }
1216 
1217 static int dma_chan_pause(struct dma_chan *dchan)
1218 {
1219 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1220 	unsigned long flags;
1221 	unsigned int timeout = 20; /* timeout iterations */
1222 	u64 val;
1223 
1224 	spin_lock_irqsave(&chan->vc.lock, flags);
1225 
1226 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
1227 		val = axi_dma_ioread64(chan->chip, DMAC_CHSUSPREG);
1228 		if (chan->id >= DMAC_CHAN_16) {
1229 			val |= (u64)(BIT(chan->id) >> DMAC_CHAN_16)
1230 				<< (DMAC_CHAN_SUSP2_SHIFT + DMAC_CHAN_BLOCK_SHIFT) |
1231 				(u64)(BIT(chan->id) >> DMAC_CHAN_16)
1232 				<< (DMAC_CHAN_SUSP2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT);
1233 		} else {
1234 			val |= BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT |
1235 			       BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT;
1236 			}
1237 			axi_dma_iowrite64(chan->chip, DMAC_CHSUSPREG, val);
1238 	} else {
1239 		if (chan->chip->dw->hdata->reg_map_8_channels) {
1240 			val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
1241 			val |= BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT |
1242 			BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT;
1243 			axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
1244 		} else {
1245 			val = axi_dma_ioread32(chan->chip, DMAC_CHSUSPREG);
1246 			val |= BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT |
1247 			BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT;
1248 			axi_dma_iowrite32(chan->chip, DMAC_CHSUSPREG, (u32)val);
1249 		}
1250 	}
1251 
1252 	do  {
1253 		if (axi_chan_irq_read(chan) & DWAXIDMAC_IRQ_SUSPENDED)
1254 			break;
1255 
1256 		udelay(2);
1257 	} while (--timeout);
1258 
1259 	axi_chan_irq_clear(chan, DWAXIDMAC_IRQ_SUSPENDED);
1260 
1261 	chan->is_paused = true;
1262 
1263 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1264 
1265 	return timeout ? 0 : -EAGAIN;
1266 }
1267 
1268 /* Called in chan locked context */
1269 static inline void axi_chan_resume(struct axi_dma_chan *chan)
1270 {
1271 	u64 val;
1272 
1273 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
1274 		val = axi_dma_ioread64(chan->chip, DMAC_CHSUSPREG);
1275 		if (chan->id >= DMAC_CHAN_16) {
1276 			val &= ~((u64)(BIT(chan->id) >> DMAC_CHAN_16)
1277 				<< (DMAC_CHAN_SUSP2_SHIFT + DMAC_CHAN_BLOCK_SHIFT));
1278 			val |=  ((u64)(BIT(chan->id) >> DMAC_CHAN_16)
1279 				<< (DMAC_CHAN_SUSP2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT));
1280 		} else {
1281 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT);
1282 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT);
1283 		}
1284 			axi_dma_iowrite64(chan->chip, DMAC_CHSUSPREG, val);
1285 	} else {
1286 		if (chan->chip->dw->hdata->reg_map_8_channels) {
1287 			val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
1288 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT);
1289 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT);
1290 			axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
1291 		} else {
1292 			val = axi_dma_ioread32(chan->chip, DMAC_CHSUSPREG);
1293 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT);
1294 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT);
1295 			axi_dma_iowrite32(chan->chip, DMAC_CHSUSPREG, (u32)val);
1296 		}
1297 	}
1298 
1299 	chan->is_paused = false;
1300 }
1301 
1302 static int dma_chan_resume(struct dma_chan *dchan)
1303 {
1304 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1305 	unsigned long flags;
1306 
1307 	spin_lock_irqsave(&chan->vc.lock, flags);
1308 
1309 	if (chan->is_paused)
1310 		axi_chan_resume(chan);
1311 
1312 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1313 
1314 	return 0;
1315 }
1316 
1317 static int axi_dma_suspend(struct axi_dma_chip *chip)
1318 {
1319 	axi_dma_irq_disable(chip);
1320 	axi_dma_disable(chip);
1321 
1322 	clk_disable_unprepare(chip->core_clk);
1323 	clk_disable_unprepare(chip->cfgr_clk);
1324 
1325 	return 0;
1326 }
1327 
1328 static int axi_dma_resume(struct axi_dma_chip *chip)
1329 {
1330 	int ret;
1331 
1332 	ret = clk_prepare_enable(chip->cfgr_clk);
1333 	if (ret < 0)
1334 		return ret;
1335 
1336 	ret = clk_prepare_enable(chip->core_clk);
1337 	if (ret < 0)
1338 		return ret;
1339 
1340 	axi_dma_enable(chip);
1341 	axi_dma_irq_enable(chip);
1342 
1343 	return 0;
1344 }
1345 
1346 static int __maybe_unused axi_dma_runtime_suspend(struct device *dev)
1347 {
1348 	struct axi_dma_chip *chip = dev_get_drvdata(dev);
1349 
1350 	return axi_dma_suspend(chip);
1351 }
1352 
1353 static int __maybe_unused axi_dma_runtime_resume(struct device *dev)
1354 {
1355 	struct axi_dma_chip *chip = dev_get_drvdata(dev);
1356 
1357 	return axi_dma_resume(chip);
1358 }
1359 
1360 static struct dma_chan *dw_axi_dma_of_xlate(struct of_phandle_args *dma_spec,
1361 					    struct of_dma *ofdma)
1362 {
1363 	struct dw_axi_dma *dw = ofdma->of_dma_data;
1364 	struct axi_dma_chan *chan;
1365 	struct dma_chan *dchan;
1366 
1367 	dchan = dma_get_any_slave_channel(&dw->dma);
1368 	if (!dchan)
1369 		return NULL;
1370 
1371 	chan = dchan_to_axi_dma_chan(dchan);
1372 	chan->hw_handshake_num = dma_spec->args[0];
1373 	return dchan;
1374 }
1375 
1376 static int parse_device_properties(struct axi_dma_chip *chip)
1377 {
1378 	struct device *dev = chip->dev;
1379 	u32 tmp, carr[DMAC_MAX_CHANNELS];
1380 	int ret;
1381 
1382 	ret = device_property_read_u32(dev, "dma-channels", &tmp);
1383 	if (ret)
1384 		return ret;
1385 	if (tmp == 0 || tmp > DMAC_MAX_CHANNELS)
1386 		return -EINVAL;
1387 
1388 	chip->dw->hdata->nr_channels = tmp;
1389 	if (tmp <= DMA_REG_MAP_CH_REF)
1390 		chip->dw->hdata->reg_map_8_channels = true;
1391 
1392 	ret = device_property_read_u32(dev, "snps,dma-masters", &tmp);
1393 	if (ret)
1394 		return ret;
1395 	if (tmp == 0 || tmp > DMAC_MAX_MASTERS)
1396 		return -EINVAL;
1397 
1398 	chip->dw->hdata->nr_masters = tmp;
1399 
1400 	ret = device_property_read_u32(dev, "snps,data-width", &tmp);
1401 	if (ret)
1402 		return ret;
1403 	if (tmp > DWAXIDMAC_TRANS_WIDTH_MAX)
1404 		return -EINVAL;
1405 
1406 	chip->dw->hdata->m_data_width = tmp;
1407 
1408 	ret = device_property_read_u32_array(dev, "snps,block-size", carr,
1409 					     chip->dw->hdata->nr_channels);
1410 	if (ret)
1411 		return ret;
1412 	for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
1413 		if (carr[tmp] == 0 || carr[tmp] > DMAC_MAX_BLK_SIZE)
1414 			return -EINVAL;
1415 
1416 		chip->dw->hdata->block_size[tmp] = carr[tmp];
1417 	}
1418 
1419 	ret = device_property_read_u32_array(dev, "snps,priority", carr,
1420 					     chip->dw->hdata->nr_channels);
1421 	if (ret)
1422 		return ret;
1423 	/* Priority value must be programmed within [0:nr_channels-1] range */
1424 	for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
1425 		if (carr[tmp] >= chip->dw->hdata->nr_channels)
1426 			return -EINVAL;
1427 
1428 		chip->dw->hdata->priority[tmp] = carr[tmp];
1429 	}
1430 
1431 	/* axi-max-burst-len is optional property */
1432 	ret = device_property_read_u32(dev, "snps,axi-max-burst-len", &tmp);
1433 	if (!ret) {
1434 		if (tmp > DWAXIDMAC_ARWLEN_MAX + 1)
1435 			return -EINVAL;
1436 		if (tmp < DWAXIDMAC_ARWLEN_MIN + 1)
1437 			return -EINVAL;
1438 
1439 		chip->dw->hdata->restrict_axi_burst_len = true;
1440 		chip->dw->hdata->axi_rw_burst_len = tmp;
1441 	}
1442 
1443 	return 0;
1444 }
1445 
1446 static int axi_req_irqs(struct platform_device *pdev, struct axi_dma_chip *chip)
1447 {
1448 	int irq_count = platform_irq_count(pdev);
1449 	int ret;
1450 
1451 	for (int i = 0; i < irq_count; i++) {
1452 		chip->irq[i] = platform_get_irq(pdev, i);
1453 		if (chip->irq[i] < 0)
1454 			return chip->irq[i];
1455 		ret = devm_request_irq(chip->dev, chip->irq[i], dw_axi_dma_interrupt,
1456 				IRQF_SHARED, KBUILD_MODNAME, chip);
1457 		if (ret < 0)
1458 			return ret;
1459 	}
1460 
1461 	return 0;
1462 }
1463 
1464 static int dw_probe(struct platform_device *pdev)
1465 {
1466 	struct axi_dma_chip *chip;
1467 	struct dw_axi_dma *dw;
1468 	struct dw_axi_dma_hcfg *hdata;
1469 	struct reset_control *resets;
1470 	unsigned int flags;
1471 	u32 i;
1472 	int ret;
1473 
1474 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
1475 	if (!chip)
1476 		return -ENOMEM;
1477 
1478 	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
1479 	if (!dw)
1480 		return -ENOMEM;
1481 
1482 	hdata = devm_kzalloc(&pdev->dev, sizeof(*hdata), GFP_KERNEL);
1483 	if (!hdata)
1484 		return -ENOMEM;
1485 
1486 	chip->dw = dw;
1487 	chip->dev = &pdev->dev;
1488 	chip->dw->hdata = hdata;
1489 
1490 	chip->regs = devm_platform_ioremap_resource(pdev, 0);
1491 	if (IS_ERR(chip->regs))
1492 		return PTR_ERR(chip->regs);
1493 
1494 	flags = (uintptr_t)of_device_get_match_data(&pdev->dev);
1495 	if (flags & AXI_DMA_FLAG_HAS_APB_REGS) {
1496 		chip->apb_regs = devm_platform_ioremap_resource(pdev, 1);
1497 		if (IS_ERR(chip->apb_regs))
1498 			return PTR_ERR(chip->apb_regs);
1499 	}
1500 
1501 	if (flags & AXI_DMA_FLAG_HAS_RESETS) {
1502 		resets = devm_reset_control_array_get_exclusive(&pdev->dev);
1503 		if (IS_ERR(resets))
1504 			return PTR_ERR(resets);
1505 
1506 		ret = reset_control_deassert(resets);
1507 		if (ret)
1508 			return ret;
1509 	}
1510 
1511 	chip->dw->hdata->use_cfg2 = !!(flags & AXI_DMA_FLAG_USE_CFG2);
1512 
1513 	chip->core_clk = devm_clk_get(chip->dev, "core-clk");
1514 	if (IS_ERR(chip->core_clk))
1515 		return PTR_ERR(chip->core_clk);
1516 
1517 	chip->cfgr_clk = devm_clk_get(chip->dev, "cfgr-clk");
1518 	if (IS_ERR(chip->cfgr_clk))
1519 		return PTR_ERR(chip->cfgr_clk);
1520 
1521 	ret = parse_device_properties(chip);
1522 	if (ret)
1523 		return ret;
1524 
1525 	dw->chan = devm_kcalloc(chip->dev, hdata->nr_channels,
1526 				sizeof(*dw->chan), GFP_KERNEL);
1527 	if (!dw->chan)
1528 		return -ENOMEM;
1529 
1530 	ret = axi_req_irqs(pdev, chip);
1531 	if (ret)
1532 		return ret;
1533 
1534 	INIT_LIST_HEAD(&dw->dma.channels);
1535 	for (i = 0; i < hdata->nr_channels; i++) {
1536 		struct axi_dma_chan *chan = &dw->chan[i];
1537 
1538 		chan->chip = chip;
1539 		chan->id = i;
1540 		chan->chan_regs = chip->regs + COMMON_REG_LEN + i * CHAN_REG_LEN;
1541 		atomic_set(&chan->descs_allocated, 0);
1542 
1543 		chan->vc.desc_free = vchan_desc_put;
1544 		vchan_init(&chan->vc, &dw->dma);
1545 	}
1546 
1547 	/* Set capabilities */
1548 	dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
1549 	dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
1550 	dma_cap_set(DMA_CYCLIC, dw->dma.cap_mask);
1551 
1552 	/* DMA capabilities */
1553 	dw->dma.max_burst = hdata->axi_rw_burst_len;
1554 	dw->dma.src_addr_widths = AXI_DMA_BUSWIDTHS;
1555 	dw->dma.dst_addr_widths = AXI_DMA_BUSWIDTHS;
1556 	dw->dma.directions = BIT(DMA_MEM_TO_MEM);
1557 	dw->dma.directions |= BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1558 	dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1559 
1560 	dw->dma.dev = chip->dev;
1561 	dw->dma.device_tx_status = dma_chan_tx_status;
1562 	dw->dma.device_issue_pending = dma_chan_issue_pending;
1563 	dw->dma.device_terminate_all = dma_chan_terminate_all;
1564 	dw->dma.device_pause = dma_chan_pause;
1565 	dw->dma.device_resume = dma_chan_resume;
1566 
1567 	dw->dma.device_alloc_chan_resources = dma_chan_alloc_chan_resources;
1568 	dw->dma.device_free_chan_resources = dma_chan_free_chan_resources;
1569 
1570 	dw->dma.device_prep_dma_memcpy = dma_chan_prep_dma_memcpy;
1571 	dw->dma.device_synchronize = dw_axi_dma_synchronize;
1572 	dw->dma.device_config = dw_axi_dma_chan_slave_config;
1573 	dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
1574 	dw->dma.device_prep_dma_cyclic = dw_axi_dma_chan_prep_cyclic;
1575 
1576 	/*
1577 	 * Synopsis DesignWare AxiDMA datasheet mentioned Maximum
1578 	 * supported blocks is 1024. Device register width is 4 bytes.
1579 	 * Therefore, set constraint to 1024 * 4.
1580 	 */
1581 	dw->dma.dev->dma_parms = &dw->dma_parms;
1582 	dma_set_max_seg_size(&pdev->dev, MAX_BLOCK_SIZE);
1583 	platform_set_drvdata(pdev, chip);
1584 
1585 	pm_runtime_enable(chip->dev);
1586 
1587 	/*
1588 	 * We can't just call pm_runtime_get here instead of
1589 	 * pm_runtime_get_noresume + axi_dma_resume because we need
1590 	 * driver to work also without Runtime PM.
1591 	 */
1592 	pm_runtime_get_noresume(chip->dev);
1593 	ret = axi_dma_resume(chip);
1594 	if (ret < 0)
1595 		goto err_pm_disable;
1596 
1597 	axi_dma_hw_init(chip);
1598 
1599 	pm_runtime_put(chip->dev);
1600 
1601 	ret = dmaenginem_async_device_register(&dw->dma);
1602 	if (ret)
1603 		goto err_pm_disable;
1604 
1605 	/* Register with OF helpers for DMA lookups */
1606 	ret = of_dma_controller_register(pdev->dev.of_node,
1607 					 dw_axi_dma_of_xlate, dw);
1608 	if (ret < 0)
1609 		dev_warn(&pdev->dev,
1610 			 "Failed to register OF DMA controller, fallback to MEM_TO_MEM mode\n");
1611 
1612 	dev_info(chip->dev, "DesignWare AXI DMA Controller, %d channels\n",
1613 		 dw->hdata->nr_channels);
1614 
1615 	return 0;
1616 
1617 err_pm_disable:
1618 	pm_runtime_disable(chip->dev);
1619 
1620 	return ret;
1621 }
1622 
1623 static void dw_remove(struct platform_device *pdev)
1624 {
1625 	struct axi_dma_chip *chip = platform_get_drvdata(pdev);
1626 	struct dw_axi_dma *dw = chip->dw;
1627 	struct axi_dma_chan *chan, *_chan;
1628 	u32 i;
1629 
1630 	/* Enable clk before accessing to registers */
1631 	clk_prepare_enable(chip->cfgr_clk);
1632 	clk_prepare_enable(chip->core_clk);
1633 	axi_dma_irq_disable(chip);
1634 	for (i = 0; i < dw->hdata->nr_channels; i++) {
1635 		axi_chan_disable(&chip->dw->chan[i]);
1636 		axi_chan_irq_disable(&chip->dw->chan[i], DWAXIDMAC_IRQ_ALL);
1637 	}
1638 	axi_dma_disable(chip);
1639 
1640 	pm_runtime_disable(chip->dev);
1641 	axi_dma_suspend(chip);
1642 
1643 	for (i = 0; i < DMAC_MAX_CHANNELS; i++)
1644 		if (chip->irq[i] > 0)
1645 			devm_free_irq(chip->dev, chip->irq[i], chip);
1646 
1647 	of_dma_controller_free(chip->dev->of_node);
1648 
1649 	list_for_each_entry_safe(chan, _chan, &dw->dma.channels,
1650 			vc.chan.device_node) {
1651 		list_del(&chan->vc.chan.device_node);
1652 		tasklet_kill(&chan->vc.task);
1653 	}
1654 }
1655 
1656 static const struct dev_pm_ops dw_axi_dma_pm_ops = {
1657 	SET_RUNTIME_PM_OPS(axi_dma_runtime_suspend, axi_dma_runtime_resume, NULL)
1658 };
1659 
1660 static const struct of_device_id dw_dma_of_id_table[] = {
1661 	{
1662 		.compatible = "snps,axi-dma-1.01a"
1663 	}, {
1664 		.compatible = "intel,kmb-axi-dma",
1665 		.data = (void *)AXI_DMA_FLAG_HAS_APB_REGS,
1666 	}, {
1667 		.compatible = "starfive,jh7110-axi-dma",
1668 		.data = (void *)(AXI_DMA_FLAG_HAS_RESETS | AXI_DMA_FLAG_USE_CFG2),
1669 	}, {
1670 		.compatible = "starfive,jh8100-axi-dma",
1671 		.data = (void *)AXI_DMA_FLAG_HAS_RESETS,
1672 	},
1673 	{}
1674 };
1675 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
1676 
1677 static struct platform_driver dw_driver = {
1678 	.probe		= dw_probe,
1679 	.remove		= dw_remove,
1680 	.driver = {
1681 		.name	= KBUILD_MODNAME,
1682 		.of_match_table = dw_dma_of_id_table,
1683 		.pm = &dw_axi_dma_pm_ops,
1684 	},
1685 };
1686 module_platform_driver(dw_driver);
1687 
1688 MODULE_LICENSE("GPL v2");
1689 MODULE_DESCRIPTION("Synopsys DesignWare AXI DMA Controller platform driver");
1690 MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
1691