xref: /linux/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c (revision 0ea5c948cb64bab5bc7a5516774eb8536f05aa0d)
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 
306 	return desc;
307 }
308 
309 static struct axi_dma_lli *axi_desc_get(struct axi_dma_chan *chan,
310 					dma_addr_t *addr)
311 {
312 	struct axi_dma_lli *lli;
313 	dma_addr_t phys;
314 
315 	lli = dma_pool_zalloc(chan->desc_pool, GFP_NOWAIT, &phys);
316 	if (unlikely(!lli)) {
317 		dev_err(chan2dev(chan), "%s: not enough descriptors available\n",
318 			axi_chan_name(chan));
319 		return NULL;
320 	}
321 
322 	atomic_inc(&chan->descs_allocated);
323 	*addr = phys;
324 
325 	return lli;
326 }
327 
328 static void axi_desc_put(struct axi_dma_desc *desc)
329 {
330 	struct axi_dma_chan *chan = desc->chan;
331 	int count = atomic_read(&chan->descs_allocated);
332 	struct axi_dma_hw_desc *hw_desc;
333 	int descs_put;
334 
335 	for (descs_put = 0; descs_put < count; descs_put++) {
336 		hw_desc = &desc->hw_desc[descs_put];
337 		dma_pool_free(chan->desc_pool, hw_desc->lli, hw_desc->llp);
338 	}
339 
340 	kfree(desc->hw_desc);
341 	kfree(desc);
342 	atomic_sub(descs_put, &chan->descs_allocated);
343 	dev_vdbg(chan2dev(chan), "%s: %d descs put, %d still allocated\n",
344 		axi_chan_name(chan), descs_put,
345 		atomic_read(&chan->descs_allocated));
346 }
347 
348 static void vchan_desc_put(struct virt_dma_desc *vdesc)
349 {
350 	axi_desc_put(vd_to_axi_desc(vdesc));
351 }
352 
353 static enum dma_status
354 dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
355 		  struct dma_tx_state *txstate)
356 {
357 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
358 	struct virt_dma_desc *vdesc;
359 	enum dma_status status;
360 	u32 completed_length;
361 	unsigned long flags;
362 	u32 completed_blocks;
363 	size_t bytes = 0;
364 	u32 length;
365 	u32 len;
366 
367 	status = dma_cookie_status(dchan, cookie, txstate);
368 	if (status == DMA_COMPLETE || !txstate)
369 		return status;
370 
371 	spin_lock_irqsave(&chan->vc.lock, flags);
372 
373 	vdesc = vchan_find_desc(&chan->vc, cookie);
374 	if (vdesc) {
375 		length = vd_to_axi_desc(vdesc)->length;
376 		completed_blocks = vd_to_axi_desc(vdesc)->completed_blocks;
377 		len = vd_to_axi_desc(vdesc)->hw_desc[0].len;
378 		completed_length = completed_blocks * len;
379 		bytes = length - completed_length;
380 	}
381 
382 	spin_unlock_irqrestore(&chan->vc.lock, flags);
383 	dma_set_residue(txstate, bytes);
384 
385 	return status;
386 }
387 
388 static void write_desc_llp(struct axi_dma_hw_desc *desc, dma_addr_t adr)
389 {
390 	desc->lli->llp = cpu_to_le64(adr);
391 }
392 
393 static void write_chan_llp(struct axi_dma_chan *chan, dma_addr_t adr)
394 {
395 	axi_chan_iowrite64(chan, CH_LLP, adr);
396 }
397 
398 static void dw_axi_dma_set_byte_halfword(struct axi_dma_chan *chan, bool set)
399 {
400 	u32 offset = DMAC_APB_BYTE_WR_CH_EN;
401 	u32 reg_width, val;
402 
403 	if (!chan->chip->apb_regs) {
404 		dev_dbg(chan->chip->dev, "apb_regs not initialized\n");
405 		return;
406 	}
407 
408 	reg_width = __ffs(chan->config.dst_addr_width);
409 	if (reg_width == DWAXIDMAC_TRANS_WIDTH_16)
410 		offset = DMAC_APB_HALFWORD_WR_CH_EN;
411 
412 	val = ioread32(chan->chip->apb_regs + offset);
413 
414 	if (set)
415 		val |= BIT(chan->id);
416 	else
417 		val &= ~BIT(chan->id);
418 
419 	iowrite32(val, chan->chip->apb_regs + offset);
420 }
421 /* Called in chan locked context */
422 static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
423 				      struct axi_dma_desc *first)
424 {
425 	u32 priority = chan->chip->dw->hdata->priority[chan->id];
426 	struct axi_dma_chan_config config = {};
427 	u32 irq_mask;
428 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
429 
430 	if (unlikely(axi_chan_is_hw_enable(chan))) {
431 		dev_err(chan2dev(chan), "%s is non-idle!\n",
432 			axi_chan_name(chan));
433 
434 		return;
435 	}
436 
437 	axi_dma_enable(chan->chip);
438 
439 	config.dst_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
440 	config.src_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
441 	config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
442 	config.prior = priority;
443 	config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
444 	config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
445 	switch (chan->direction) {
446 	case DMA_MEM_TO_DEV:
447 		dw_axi_dma_set_byte_halfword(chan, true);
448 		config.tt_fc = chan->config.device_fc ?
449 				DWAXIDMAC_TT_FC_MEM_TO_PER_DST :
450 				DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC;
451 		if (chan->chip->apb_regs)
452 			config.dst_per = chan->id;
453 		else
454 			config.dst_per = chan->hw_handshake_num;
455 		break;
456 	case DMA_DEV_TO_MEM:
457 		config.tt_fc = chan->config.device_fc ?
458 				DWAXIDMAC_TT_FC_PER_TO_MEM_SRC :
459 				DWAXIDMAC_TT_FC_PER_TO_MEM_DMAC;
460 		if (chan->chip->apb_regs)
461 			config.src_per = chan->id;
462 		else
463 			config.src_per = chan->hw_handshake_num;
464 		break;
465 	default:
466 		break;
467 	}
468 	axi_chan_config_write(chan, &config);
469 
470 	write_chan_llp(chan, first->hw_desc[0].llp | lms);
471 
472 	irq_mask = DWAXIDMAC_IRQ_DMA_TRF | DWAXIDMAC_IRQ_ALL_ERR;
473 	axi_chan_irq_sig_set(chan, irq_mask);
474 
475 	/* Generate 'suspend' status but don't generate interrupt */
476 	irq_mask |= DWAXIDMAC_IRQ_SUSPENDED;
477 	axi_chan_irq_set(chan, irq_mask);
478 
479 	axi_chan_enable(chan);
480 }
481 
482 static void axi_chan_start_first_queued(struct axi_dma_chan *chan)
483 {
484 	struct axi_dma_desc *desc;
485 	struct virt_dma_desc *vd;
486 
487 	vd = vchan_next_desc(&chan->vc);
488 	if (!vd)
489 		return;
490 
491 	desc = vd_to_axi_desc(vd);
492 	dev_vdbg(chan2dev(chan), "%s: started %u\n", axi_chan_name(chan),
493 		vd->tx.cookie);
494 	axi_chan_block_xfer_start(chan, desc);
495 }
496 
497 static void dma_chan_issue_pending(struct dma_chan *dchan)
498 {
499 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
500 	unsigned long flags;
501 
502 	spin_lock_irqsave(&chan->vc.lock, flags);
503 	if (vchan_issue_pending(&chan->vc))
504 		axi_chan_start_first_queued(chan);
505 	spin_unlock_irqrestore(&chan->vc.lock, flags);
506 }
507 
508 static void dw_axi_dma_synchronize(struct dma_chan *dchan)
509 {
510 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
511 
512 	vchan_synchronize(&chan->vc);
513 }
514 
515 static int dma_chan_alloc_chan_resources(struct dma_chan *dchan)
516 {
517 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
518 
519 	/* ASSERT: channel is idle */
520 	if (axi_chan_is_hw_enable(chan)) {
521 		dev_err(chan2dev(chan), "%s is non-idle!\n",
522 			axi_chan_name(chan));
523 		return -EBUSY;
524 	}
525 
526 	/* LLI address must be aligned to a 64-byte boundary */
527 	chan->desc_pool = dma_pool_create(dev_name(chan2dev(chan)),
528 					  chan->chip->dev,
529 					  sizeof(struct axi_dma_lli),
530 					  64, 0);
531 	if (!chan->desc_pool) {
532 		dev_err(chan2dev(chan), "No memory for descriptors\n");
533 		return -ENOMEM;
534 	}
535 	dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan));
536 
537 	pm_runtime_get(chan->chip->dev);
538 
539 	return 0;
540 }
541 
542 static void dma_chan_free_chan_resources(struct dma_chan *dchan)
543 {
544 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
545 
546 	/* ASSERT: channel is idle */
547 	if (axi_chan_is_hw_enable(chan))
548 		dev_err(dchan2dev(dchan), "%s is non-idle!\n",
549 			axi_chan_name(chan));
550 
551 	axi_chan_disable(chan);
552 	axi_chan_irq_disable(chan, DWAXIDMAC_IRQ_ALL);
553 
554 	vchan_free_chan_resources(&chan->vc);
555 
556 	dma_pool_destroy(chan->desc_pool);
557 	chan->desc_pool = NULL;
558 	dev_vdbg(dchan2dev(dchan),
559 		 "%s: free resources, descriptor still allocated: %u\n",
560 		 axi_chan_name(chan), atomic_read(&chan->descs_allocated));
561 
562 	pm_runtime_put(chan->chip->dev);
563 }
564 
565 static void dw_axi_dma_set_hw_channel(struct axi_dma_chan *chan, bool set)
566 {
567 	struct axi_dma_chip *chip = chan->chip;
568 	unsigned long reg_value, val;
569 
570 	if (!chip->apb_regs) {
571 		dev_err(chip->dev, "apb_regs not initialized\n");
572 		return;
573 	}
574 
575 	/*
576 	 * An unused DMA channel has a default value of 0x3F.
577 	 * Lock the DMA channel by assign a handshake number to the channel.
578 	 * Unlock the DMA channel by assign 0x3F to the channel.
579 	 */
580 	if (set)
581 		val = chan->hw_handshake_num;
582 	else
583 		val = UNUSED_CHANNEL;
584 
585 	reg_value = lo_hi_readq(chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
586 
587 	/* Channel is already allocated, set handshake as per channel ID */
588 	/* 64 bit write should handle for 8 channels */
589 
590 	reg_value &= ~(DMA_APB_HS_SEL_MASK <<
591 			(chan->id * DMA_APB_HS_SEL_BIT_SIZE));
592 	reg_value |= (val << (chan->id * DMA_APB_HS_SEL_BIT_SIZE));
593 	lo_hi_writeq(reg_value, chip->apb_regs + DMAC_APB_HW_HS_SEL_0);
594 
595 	return;
596 }
597 
598 /*
599  * If DW_axi_dmac sees CHx_CTL.ShadowReg_Or_LLI_Last bit of the fetched LLI
600  * as 1, it understands that the current block is the final block in the
601  * transfer and completes the DMA transfer operation at the end of current
602  * block transfer.
603  */
604 static void set_desc_last(struct axi_dma_hw_desc *desc)
605 {
606 	u32 val;
607 
608 	val = le32_to_cpu(desc->lli->ctl_hi);
609 	val |= CH_CTL_H_LLI_LAST;
610 	desc->lli->ctl_hi = cpu_to_le32(val);
611 }
612 
613 static void write_desc_sar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
614 {
615 	desc->lli->sar = cpu_to_le64(adr);
616 }
617 
618 static void write_desc_dar(struct axi_dma_hw_desc *desc, dma_addr_t adr)
619 {
620 	desc->lli->dar = cpu_to_le64(adr);
621 }
622 
623 static void set_desc_src_master(struct axi_dma_hw_desc *desc)
624 {
625 	u32 val;
626 
627 	/* Select AXI0 for source master */
628 	val = le32_to_cpu(desc->lli->ctl_lo);
629 	val &= ~CH_CTL_L_SRC_MAST;
630 	desc->lli->ctl_lo = cpu_to_le32(val);
631 }
632 
633 static void set_desc_dest_master(struct axi_dma_hw_desc *hw_desc,
634 				 struct axi_dma_desc *desc)
635 {
636 	u32 val;
637 
638 	/* Select AXI1 for source master if available */
639 	val = le32_to_cpu(hw_desc->lli->ctl_lo);
640 	if (desc->chan->chip->dw->hdata->nr_masters > 1)
641 		val |= CH_CTL_L_DST_MAST;
642 	else
643 		val &= ~CH_CTL_L_DST_MAST;
644 
645 	hw_desc->lli->ctl_lo = cpu_to_le32(val);
646 }
647 
648 static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan,
649 				  struct axi_dma_hw_desc *hw_desc,
650 				  dma_addr_t mem_addr, size_t len)
651 {
652 	unsigned int data_width = BIT(chan->chip->dw->hdata->m_data_width);
653 	unsigned int reg_width;
654 	unsigned int mem_width;
655 	dma_addr_t device_addr;
656 	size_t axi_block_ts;
657 	size_t block_ts;
658 	u32 ctllo, ctlhi;
659 	u32 burst_len;
660 
661 	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
662 
663 	mem_width = __ffs(data_width | mem_addr | len);
664 	if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
665 		mem_width = DWAXIDMAC_TRANS_WIDTH_32;
666 
667 	if (!IS_ALIGNED(mem_addr, 4)) {
668 		dev_err(chan->chip->dev, "invalid buffer alignment\n");
669 		return -EINVAL;
670 	}
671 
672 	switch (chan->direction) {
673 	case DMA_MEM_TO_DEV:
674 		reg_width = __ffs(chan->config.dst_addr_width);
675 		device_addr = chan->config.dst_addr;
676 		ctllo = reg_width << CH_CTL_L_DST_WIDTH_POS |
677 			mem_width << CH_CTL_L_SRC_WIDTH_POS |
678 			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_DST_INC_POS |
679 			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS;
680 		block_ts = len >> mem_width;
681 		break;
682 	case DMA_DEV_TO_MEM:
683 		reg_width = __ffs(chan->config.src_addr_width);
684 		device_addr = chan->config.src_addr;
685 		ctllo = reg_width << CH_CTL_L_SRC_WIDTH_POS |
686 			mem_width << CH_CTL_L_DST_WIDTH_POS |
687 			DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
688 			DWAXIDMAC_CH_CTL_L_NOINC << CH_CTL_L_SRC_INC_POS;
689 		block_ts = len >> reg_width;
690 		break;
691 	default:
692 		return -EINVAL;
693 	}
694 
695 	if (block_ts > axi_block_ts)
696 		return -EINVAL;
697 
698 	hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
699 	if (unlikely(!hw_desc->lli))
700 		return -ENOMEM;
701 
702 	ctlhi = CH_CTL_H_LLI_VALID;
703 
704 	if (chan->chip->dw->hdata->restrict_axi_burst_len) {
705 		burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
706 		ctlhi |= CH_CTL_H_ARLEN_EN | CH_CTL_H_AWLEN_EN |
707 			 burst_len << CH_CTL_H_ARLEN_POS |
708 			 burst_len << CH_CTL_H_AWLEN_POS;
709 	}
710 
711 	hw_desc->lli->ctl_hi = cpu_to_le32(ctlhi);
712 
713 	if (chan->direction == DMA_MEM_TO_DEV) {
714 		write_desc_sar(hw_desc, mem_addr);
715 		write_desc_dar(hw_desc, device_addr);
716 	} else {
717 		write_desc_sar(hw_desc, device_addr);
718 		write_desc_dar(hw_desc, mem_addr);
719 	}
720 
721 	hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
722 
723 	ctllo |= DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
724 		 DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS;
725 	hw_desc->lli->ctl_lo = cpu_to_le32(ctllo);
726 
727 	set_desc_src_master(hw_desc);
728 
729 	hw_desc->len = len;
730 	return 0;
731 }
732 
733 static size_t calculate_block_len(struct axi_dma_chan *chan,
734 				  dma_addr_t dma_addr, size_t buf_len,
735 				  enum dma_transfer_direction direction)
736 {
737 	u32 data_width, reg_width, mem_width;
738 	size_t axi_block_ts, block_len;
739 
740 	axi_block_ts = chan->chip->dw->hdata->block_size[chan->id];
741 
742 	switch (direction) {
743 	case DMA_MEM_TO_DEV:
744 		data_width = BIT(chan->chip->dw->hdata->m_data_width);
745 		mem_width = __ffs(data_width | dma_addr | buf_len);
746 		if (mem_width > DWAXIDMAC_TRANS_WIDTH_32)
747 			mem_width = DWAXIDMAC_TRANS_WIDTH_32;
748 
749 		block_len = axi_block_ts << mem_width;
750 		break;
751 	case DMA_DEV_TO_MEM:
752 		reg_width = __ffs(chan->config.src_addr_width);
753 		block_len = axi_block_ts << reg_width;
754 		break;
755 	default:
756 		block_len = 0;
757 	}
758 
759 	return block_len;
760 }
761 
762 static struct dma_async_tx_descriptor *
763 dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr,
764 			    size_t buf_len, size_t period_len,
765 			    enum dma_transfer_direction direction,
766 			    unsigned long flags)
767 {
768 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
769 	struct axi_dma_hw_desc *hw_desc = NULL;
770 	struct axi_dma_desc *desc = NULL;
771 	dma_addr_t src_addr = dma_addr;
772 	u32 num_periods, num_segments;
773 	size_t axi_block_len;
774 	u32 total_segments;
775 	u32 segment_len;
776 	unsigned int i;
777 	int status;
778 	u64 llp = 0;
779 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
780 
781 	num_periods = buf_len / period_len;
782 
783 	axi_block_len = calculate_block_len(chan, dma_addr, buf_len, direction);
784 	if (axi_block_len == 0)
785 		return NULL;
786 
787 	num_segments = DIV_ROUND_UP(period_len, axi_block_len);
788 	segment_len = DIV_ROUND_UP(period_len, num_segments);
789 
790 	total_segments = num_periods * num_segments;
791 
792 	desc = axi_desc_alloc(total_segments);
793 	if (unlikely(!desc))
794 		goto err_desc_get;
795 
796 	chan->direction = direction;
797 	desc->chan = chan;
798 	chan->cyclic = true;
799 	desc->length = 0;
800 	desc->period_len = period_len;
801 
802 	for (i = 0; i < total_segments; i++) {
803 		hw_desc = &desc->hw_desc[i];
804 
805 		status = dw_axi_dma_set_hw_desc(chan, hw_desc, src_addr,
806 						segment_len);
807 		if (status < 0)
808 			goto err_desc_get;
809 
810 		desc->length += hw_desc->len;
811 		/* Set end-of-link to the linked descriptor, so that cyclic
812 		 * callback function can be triggered during interrupt.
813 		 */
814 		set_desc_last(hw_desc);
815 
816 		src_addr += segment_len;
817 	}
818 
819 	llp = desc->hw_desc[0].llp;
820 
821 	/* Managed transfer list */
822 	do {
823 		hw_desc = &desc->hw_desc[--total_segments];
824 		write_desc_llp(hw_desc, llp | lms);
825 		llp = hw_desc->llp;
826 	} while (total_segments);
827 
828 	dw_axi_dma_set_hw_channel(chan, true);
829 
830 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
831 
832 err_desc_get:
833 	if (desc)
834 		axi_desc_put(desc);
835 
836 	return NULL;
837 }
838 
839 static struct dma_async_tx_descriptor *
840 dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
841 			      unsigned int sg_len,
842 			      enum dma_transfer_direction direction,
843 			      unsigned long flags, void *context)
844 {
845 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
846 	struct axi_dma_hw_desc *hw_desc = NULL;
847 	struct axi_dma_desc *desc = NULL;
848 	u32 num_segments, segment_len;
849 	unsigned int loop = 0;
850 	struct scatterlist *sg;
851 	size_t axi_block_len;
852 	u32 len, num_sgs = 0;
853 	unsigned int i;
854 	dma_addr_t mem;
855 	int status;
856 	u64 llp = 0;
857 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
858 
859 	if (unlikely(!is_slave_direction(direction) || !sg_len))
860 		return NULL;
861 
862 	mem = sg_dma_address(sgl);
863 	len = sg_dma_len(sgl);
864 
865 	axi_block_len = calculate_block_len(chan, mem, len, direction);
866 	if (axi_block_len == 0)
867 		return NULL;
868 
869 	for_each_sg(sgl, sg, sg_len, i)
870 		num_sgs += DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
871 
872 	desc = axi_desc_alloc(num_sgs);
873 	if (unlikely(!desc))
874 		goto err_desc_get;
875 
876 	desc->chan = chan;
877 	desc->length = 0;
878 	chan->direction = direction;
879 
880 	for_each_sg(sgl, sg, sg_len, i) {
881 		mem = sg_dma_address(sg);
882 		len = sg_dma_len(sg);
883 		num_segments = DIV_ROUND_UP(sg_dma_len(sg), axi_block_len);
884 		segment_len = DIV_ROUND_UP(sg_dma_len(sg), num_segments);
885 
886 		do {
887 			hw_desc = &desc->hw_desc[loop++];
888 			status = dw_axi_dma_set_hw_desc(chan, hw_desc, mem, segment_len);
889 			if (status < 0)
890 				goto err_desc_get;
891 
892 			desc->length += hw_desc->len;
893 			len -= segment_len;
894 			mem += segment_len;
895 		} while (len >= segment_len);
896 	}
897 
898 	/* Set end-of-link to the last link descriptor of list */
899 	set_desc_last(&desc->hw_desc[num_sgs - 1]);
900 
901 	/* Managed transfer list */
902 	do {
903 		hw_desc = &desc->hw_desc[--num_sgs];
904 		write_desc_llp(hw_desc, llp | lms);
905 		llp = hw_desc->llp;
906 	} while (num_sgs);
907 
908 	dw_axi_dma_set_hw_channel(chan, true);
909 
910 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
911 
912 err_desc_get:
913 	if (desc)
914 		axi_desc_put(desc);
915 
916 	return NULL;
917 }
918 
919 static struct dma_async_tx_descriptor *
920 dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr,
921 			 dma_addr_t src_adr, size_t len, unsigned long flags)
922 {
923 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
924 	size_t block_ts, max_block_ts, xfer_len;
925 	struct axi_dma_hw_desc *hw_desc = NULL;
926 	struct axi_dma_desc *desc = NULL;
927 	u32 xfer_width, reg, num;
928 	u64 llp = 0;
929 	u8 lms = 0; /* Select AXI0 master for LLI fetching */
930 
931 	dev_dbg(chan2dev(chan), "%s: memcpy: src: %pad dst: %pad length: %zd flags: %#lx",
932 		axi_chan_name(chan), &src_adr, &dst_adr, len, flags);
933 
934 	max_block_ts = chan->chip->dw->hdata->block_size[chan->id];
935 	xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, len);
936 	num = DIV_ROUND_UP(len, max_block_ts << xfer_width);
937 	desc = axi_desc_alloc(num);
938 	if (unlikely(!desc))
939 		goto err_desc_get;
940 
941 	desc->chan = chan;
942 	num = 0;
943 	desc->length = 0;
944 	while (len) {
945 		xfer_len = len;
946 
947 		hw_desc = &desc->hw_desc[num];
948 		/*
949 		 * Take care for the alignment.
950 		 * Actually source and destination widths can be different, but
951 		 * make them same to be simpler.
952 		 */
953 		xfer_width = axi_chan_get_xfer_width(chan, src_adr, dst_adr, xfer_len);
954 
955 		/*
956 		 * block_ts indicates the total number of data of width
957 		 * to be transferred in a DMA block transfer.
958 		 * BLOCK_TS register should be set to block_ts - 1
959 		 */
960 		block_ts = xfer_len >> xfer_width;
961 		if (block_ts > max_block_ts) {
962 			block_ts = max_block_ts;
963 			xfer_len = max_block_ts << xfer_width;
964 		}
965 
966 		hw_desc->lli = axi_desc_get(chan, &hw_desc->llp);
967 		if (unlikely(!hw_desc->lli))
968 			goto err_desc_get;
969 
970 		write_desc_sar(hw_desc, src_adr);
971 		write_desc_dar(hw_desc, dst_adr);
972 		hw_desc->lli->block_ts_lo = cpu_to_le32(block_ts - 1);
973 
974 		reg = CH_CTL_H_LLI_VALID;
975 		if (chan->chip->dw->hdata->restrict_axi_burst_len) {
976 			u32 burst_len = chan->chip->dw->hdata->axi_rw_burst_len;
977 
978 			reg |= (CH_CTL_H_ARLEN_EN |
979 				burst_len << CH_CTL_H_ARLEN_POS |
980 				CH_CTL_H_AWLEN_EN |
981 				burst_len << CH_CTL_H_AWLEN_POS);
982 		}
983 		hw_desc->lli->ctl_hi = cpu_to_le32(reg);
984 
985 		reg = (DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_DST_MSIZE_POS |
986 		       DWAXIDMAC_BURST_TRANS_LEN_4 << CH_CTL_L_SRC_MSIZE_POS |
987 		       xfer_width << CH_CTL_L_DST_WIDTH_POS |
988 		       xfer_width << CH_CTL_L_SRC_WIDTH_POS |
989 		       DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_DST_INC_POS |
990 		       DWAXIDMAC_CH_CTL_L_INC << CH_CTL_L_SRC_INC_POS);
991 		hw_desc->lli->ctl_lo = cpu_to_le32(reg);
992 
993 		set_desc_src_master(hw_desc);
994 		set_desc_dest_master(hw_desc, desc);
995 
996 		hw_desc->len = xfer_len;
997 		desc->length += hw_desc->len;
998 		/* update the length and addresses for the next loop cycle */
999 		len -= xfer_len;
1000 		dst_adr += xfer_len;
1001 		src_adr += xfer_len;
1002 		num++;
1003 	}
1004 
1005 	/* Set end-of-link to the last link descriptor of list */
1006 	set_desc_last(&desc->hw_desc[num - 1]);
1007 	/* Managed transfer list */
1008 	do {
1009 		hw_desc = &desc->hw_desc[--num];
1010 		write_desc_llp(hw_desc, llp | lms);
1011 		llp = hw_desc->llp;
1012 	} while (num);
1013 
1014 	return vchan_tx_prep(&chan->vc, &desc->vd, flags);
1015 
1016 err_desc_get:
1017 	if (desc)
1018 		axi_desc_put(desc);
1019 	return NULL;
1020 }
1021 
1022 static int dw_axi_dma_chan_slave_config(struct dma_chan *dchan,
1023 					struct dma_slave_config *config)
1024 {
1025 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1026 
1027 	memcpy(&chan->config, config, sizeof(*config));
1028 
1029 	return 0;
1030 }
1031 
1032 static void axi_chan_dump_lli(struct axi_dma_chan *chan,
1033 			      struct axi_dma_hw_desc *desc)
1034 {
1035 	if (!desc->lli) {
1036 		dev_err(dchan2dev(&chan->vc.chan), "NULL LLI\n");
1037 		return;
1038 	}
1039 
1040 	dev_err(dchan2dev(&chan->vc.chan),
1041 		"SAR: 0x%llx DAR: 0x%llx LLP: 0x%llx BTS 0x%x CTL: 0x%x:%08x",
1042 		le64_to_cpu(desc->lli->sar),
1043 		le64_to_cpu(desc->lli->dar),
1044 		le64_to_cpu(desc->lli->llp),
1045 		le32_to_cpu(desc->lli->block_ts_lo),
1046 		le32_to_cpu(desc->lli->ctl_hi),
1047 		le32_to_cpu(desc->lli->ctl_lo));
1048 }
1049 
1050 static void axi_chan_list_dump_lli(struct axi_dma_chan *chan,
1051 				   struct axi_dma_desc *desc_head)
1052 {
1053 	int count = atomic_read(&chan->descs_allocated);
1054 	int i;
1055 
1056 	for (i = 0; i < count; i++)
1057 		axi_chan_dump_lli(chan, &desc_head->hw_desc[i]);
1058 }
1059 
1060 static noinline void axi_chan_handle_err(struct axi_dma_chan *chan, u32 status)
1061 {
1062 	struct virt_dma_desc *vd;
1063 	unsigned long flags;
1064 
1065 	spin_lock_irqsave(&chan->vc.lock, flags);
1066 
1067 	axi_chan_disable(chan);
1068 
1069 	/* The bad descriptor currently is in the head of vc list */
1070 	vd = vchan_next_desc(&chan->vc);
1071 	if (!vd) {
1072 		dev_err(chan2dev(chan), "BUG: %s, IRQ with no descriptors\n",
1073 			axi_chan_name(chan));
1074 		goto out;
1075 	}
1076 	/* Remove the completed descriptor from issued list */
1077 	list_del(&vd->node);
1078 
1079 	/* WARN about bad descriptor */
1080 	dev_err(chan2dev(chan),
1081 		"Bad descriptor submitted for %s, cookie: %d, irq: 0x%08x\n",
1082 		axi_chan_name(chan), vd->tx.cookie, status);
1083 	axi_chan_list_dump_lli(chan, vd_to_axi_desc(vd));
1084 
1085 	vchan_cookie_complete(vd);
1086 
1087 	/* Try to restart the controller */
1088 	axi_chan_start_first_queued(chan);
1089 
1090 out:
1091 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1092 }
1093 
1094 static void axi_chan_block_xfer_complete(struct axi_dma_chan *chan)
1095 {
1096 	int count = atomic_read(&chan->descs_allocated);
1097 	struct axi_dma_hw_desc *hw_desc;
1098 	struct axi_dma_desc *desc;
1099 	struct virt_dma_desc *vd;
1100 	unsigned long flags;
1101 	u64 llp;
1102 	int i;
1103 
1104 	spin_lock_irqsave(&chan->vc.lock, flags);
1105 	if (unlikely(axi_chan_is_hw_enable(chan))) {
1106 		dev_err(chan2dev(chan), "BUG: %s caught DWAXIDMAC_IRQ_DMA_TRF, but channel not idle!\n",
1107 			axi_chan_name(chan));
1108 		axi_chan_disable(chan);
1109 	}
1110 
1111 	/* The completed descriptor currently is in the head of vc list */
1112 	vd = vchan_next_desc(&chan->vc);
1113 	if (!vd) {
1114 		dev_err(chan2dev(chan), "BUG: %s, IRQ with no descriptors\n",
1115 			axi_chan_name(chan));
1116 		goto out;
1117 	}
1118 
1119 	if (chan->cyclic) {
1120 		desc = vd_to_axi_desc(vd);
1121 		if (desc) {
1122 			llp = lo_hi_readq(chan->chan_regs + CH_LLP);
1123 			for (i = 0; i < count; i++) {
1124 				hw_desc = &desc->hw_desc[i];
1125 				if (hw_desc->llp == llp) {
1126 					axi_chan_irq_clear(chan, hw_desc->lli->status_lo);
1127 					hw_desc->lli->ctl_hi |= CH_CTL_H_LLI_VALID;
1128 					desc->completed_blocks = i;
1129 
1130 					if (((hw_desc->len * (i + 1)) % desc->period_len) == 0)
1131 						vchan_cyclic_callback(vd);
1132 					break;
1133 				}
1134 			}
1135 
1136 			axi_chan_enable(chan);
1137 		}
1138 	} else {
1139 		/* Remove the completed descriptor from issued list before completing */
1140 		list_del(&vd->node);
1141 		vchan_cookie_complete(vd);
1142 
1143 		/* Submit queued descriptors after processing the completed ones */
1144 		axi_chan_start_first_queued(chan);
1145 	}
1146 
1147 out:
1148 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1149 }
1150 
1151 static irqreturn_t dw_axi_dma_interrupt(int irq, void *dev_id)
1152 {
1153 	struct axi_dma_chip *chip = dev_id;
1154 	struct dw_axi_dma *dw = chip->dw;
1155 	struct axi_dma_chan *chan;
1156 
1157 	u32 status, i;
1158 
1159 	/* Disable DMAC interrupts. We'll enable them after processing channels */
1160 	axi_dma_irq_disable(chip);
1161 
1162 	/* Poll, clear and process every channel interrupt status */
1163 	for (i = 0; i < dw->hdata->nr_channels; i++) {
1164 		chan = &dw->chan[i];
1165 		status = axi_chan_irq_read(chan);
1166 		axi_chan_irq_clear(chan, status);
1167 
1168 		dev_vdbg(chip->dev, "%s %u IRQ status: 0x%08x\n",
1169 			axi_chan_name(chan), i, status);
1170 
1171 		if (status & DWAXIDMAC_IRQ_ALL_ERR)
1172 			axi_chan_handle_err(chan, status);
1173 		else if (status & DWAXIDMAC_IRQ_DMA_TRF)
1174 			axi_chan_block_xfer_complete(chan);
1175 	}
1176 
1177 	/* Re-enable interrupts */
1178 	axi_dma_irq_enable(chip);
1179 
1180 	return IRQ_HANDLED;
1181 }
1182 
1183 static int dma_chan_terminate_all(struct dma_chan *dchan)
1184 {
1185 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1186 	u32 chan_active = BIT(chan->id) << DMAC_CHAN_EN_SHIFT;
1187 	unsigned long flags;
1188 	u32 val;
1189 	int ret;
1190 	LIST_HEAD(head);
1191 
1192 	axi_chan_disable(chan);
1193 
1194 	ret = readl_poll_timeout_atomic(chan->chip->regs + DMAC_CHEN, val,
1195 					!(val & chan_active), 1000, 50000);
1196 	if (ret == -ETIMEDOUT)
1197 		dev_warn(dchan2dev(dchan),
1198 			 "%s failed to stop\n", axi_chan_name(chan));
1199 
1200 	if (chan->direction != DMA_MEM_TO_MEM)
1201 		dw_axi_dma_set_hw_channel(chan, false);
1202 	if (chan->direction == DMA_MEM_TO_DEV)
1203 		dw_axi_dma_set_byte_halfword(chan, false);
1204 
1205 	spin_lock_irqsave(&chan->vc.lock, flags);
1206 
1207 	vchan_get_all_descriptors(&chan->vc, &head);
1208 
1209 	chan->cyclic = false;
1210 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1211 
1212 	vchan_dma_desc_free_list(&chan->vc, &head);
1213 
1214 	dev_vdbg(dchan2dev(dchan), "terminated: %s\n", axi_chan_name(chan));
1215 
1216 	return 0;
1217 }
1218 
1219 static int dma_chan_pause(struct dma_chan *dchan)
1220 {
1221 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1222 	unsigned long flags;
1223 	unsigned int timeout = 20; /* timeout iterations */
1224 	u64 val;
1225 
1226 	spin_lock_irqsave(&chan->vc.lock, flags);
1227 
1228 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
1229 		val = axi_dma_ioread64(chan->chip, DMAC_CHSUSPREG);
1230 		if (chan->id >= DMAC_CHAN_16) {
1231 			val |= (u64)(BIT(chan->id) >> DMAC_CHAN_16)
1232 				<< (DMAC_CHAN_SUSP2_SHIFT + DMAC_CHAN_BLOCK_SHIFT) |
1233 				(u64)(BIT(chan->id) >> DMAC_CHAN_16)
1234 				<< (DMAC_CHAN_SUSP2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT);
1235 		} else {
1236 			val |= BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT |
1237 			       BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT;
1238 			}
1239 			axi_dma_iowrite64(chan->chip, DMAC_CHSUSPREG, val);
1240 	} else {
1241 		if (chan->chip->dw->hdata->reg_map_8_channels) {
1242 			val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
1243 			val |= BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT |
1244 			BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT;
1245 			axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
1246 		} else {
1247 			val = axi_dma_ioread32(chan->chip, DMAC_CHSUSPREG);
1248 			val |= BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT |
1249 			BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT;
1250 			axi_dma_iowrite32(chan->chip, DMAC_CHSUSPREG, (u32)val);
1251 		}
1252 	}
1253 
1254 	do  {
1255 		if (axi_chan_irq_read(chan) & DWAXIDMAC_IRQ_SUSPENDED)
1256 			break;
1257 
1258 		udelay(2);
1259 	} while (--timeout);
1260 
1261 	axi_chan_irq_clear(chan, DWAXIDMAC_IRQ_SUSPENDED);
1262 
1263 	chan->is_paused = true;
1264 
1265 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1266 
1267 	return timeout ? 0 : -EAGAIN;
1268 }
1269 
1270 /* Called in chan locked context */
1271 static inline void axi_chan_resume(struct axi_dma_chan *chan)
1272 {
1273 	u64 val;
1274 
1275 	if (chan->chip->dw->hdata->nr_channels >= DMAC_CHAN_16) {
1276 		val = axi_dma_ioread64(chan->chip, DMAC_CHSUSPREG);
1277 		if (chan->id >= DMAC_CHAN_16) {
1278 			val &= ~((u64)(BIT(chan->id) >> DMAC_CHAN_16)
1279 				<< (DMAC_CHAN_SUSP2_SHIFT + DMAC_CHAN_BLOCK_SHIFT));
1280 			val |=  ((u64)(BIT(chan->id) >> DMAC_CHAN_16)
1281 				<< (DMAC_CHAN_SUSP2_WE_SHIFT + DMAC_CHAN_BLOCK_SHIFT));
1282 		} else {
1283 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT);
1284 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT);
1285 		}
1286 			axi_dma_iowrite64(chan->chip, DMAC_CHSUSPREG, val);
1287 	} else {
1288 		if (chan->chip->dw->hdata->reg_map_8_channels) {
1289 			val = axi_dma_ioread32(chan->chip, DMAC_CHEN);
1290 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP_SHIFT);
1291 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP_WE_SHIFT);
1292 			axi_dma_iowrite32(chan->chip, DMAC_CHEN, (u32)val);
1293 		} else {
1294 			val = axi_dma_ioread32(chan->chip, DMAC_CHSUSPREG);
1295 			val &= ~(BIT(chan->id) << DMAC_CHAN_SUSP2_SHIFT);
1296 			val |=  (BIT(chan->id) << DMAC_CHAN_SUSP2_WE_SHIFT);
1297 			axi_dma_iowrite32(chan->chip, DMAC_CHSUSPREG, (u32)val);
1298 		}
1299 	}
1300 
1301 	chan->is_paused = false;
1302 }
1303 
1304 static int dma_chan_resume(struct dma_chan *dchan)
1305 {
1306 	struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan);
1307 	unsigned long flags;
1308 
1309 	spin_lock_irqsave(&chan->vc.lock, flags);
1310 
1311 	if (chan->is_paused)
1312 		axi_chan_resume(chan);
1313 
1314 	spin_unlock_irqrestore(&chan->vc.lock, flags);
1315 
1316 	return 0;
1317 }
1318 
1319 static int axi_dma_suspend(struct axi_dma_chip *chip)
1320 {
1321 	axi_dma_irq_disable(chip);
1322 	axi_dma_disable(chip);
1323 
1324 	clk_disable_unprepare(chip->core_clk);
1325 	clk_disable_unprepare(chip->cfgr_clk);
1326 
1327 	return 0;
1328 }
1329 
1330 static int axi_dma_resume(struct axi_dma_chip *chip)
1331 {
1332 	int ret;
1333 
1334 	ret = clk_prepare_enable(chip->cfgr_clk);
1335 	if (ret < 0)
1336 		return ret;
1337 
1338 	ret = clk_prepare_enable(chip->core_clk);
1339 	if (ret < 0)
1340 		return ret;
1341 
1342 	axi_dma_enable(chip);
1343 	axi_dma_irq_enable(chip);
1344 
1345 	return 0;
1346 }
1347 
1348 static int __maybe_unused axi_dma_runtime_suspend(struct device *dev)
1349 {
1350 	struct axi_dma_chip *chip = dev_get_drvdata(dev);
1351 
1352 	return axi_dma_suspend(chip);
1353 }
1354 
1355 static int __maybe_unused axi_dma_runtime_resume(struct device *dev)
1356 {
1357 	struct axi_dma_chip *chip = dev_get_drvdata(dev);
1358 
1359 	return axi_dma_resume(chip);
1360 }
1361 
1362 static struct dma_chan *dw_axi_dma_of_xlate(struct of_phandle_args *dma_spec,
1363 					    struct of_dma *ofdma)
1364 {
1365 	struct dw_axi_dma *dw = ofdma->of_dma_data;
1366 	struct axi_dma_chan *chan;
1367 	struct dma_chan *dchan;
1368 
1369 	dchan = dma_get_any_slave_channel(&dw->dma);
1370 	if (!dchan)
1371 		return NULL;
1372 
1373 	chan = dchan_to_axi_dma_chan(dchan);
1374 	chan->hw_handshake_num = dma_spec->args[0];
1375 	return dchan;
1376 }
1377 
1378 static int parse_device_properties(struct axi_dma_chip *chip)
1379 {
1380 	struct device *dev = chip->dev;
1381 	u32 tmp, carr[DMAC_MAX_CHANNELS];
1382 	int ret;
1383 
1384 	ret = device_property_read_u32(dev, "dma-channels", &tmp);
1385 	if (ret)
1386 		return ret;
1387 	if (tmp == 0 || tmp > DMAC_MAX_CHANNELS)
1388 		return -EINVAL;
1389 
1390 	chip->dw->hdata->nr_channels = tmp;
1391 	if (tmp <= DMA_REG_MAP_CH_REF)
1392 		chip->dw->hdata->reg_map_8_channels = true;
1393 
1394 	ret = device_property_read_u32(dev, "snps,dma-masters", &tmp);
1395 	if (ret)
1396 		return ret;
1397 	if (tmp == 0 || tmp > DMAC_MAX_MASTERS)
1398 		return -EINVAL;
1399 
1400 	chip->dw->hdata->nr_masters = tmp;
1401 
1402 	ret = device_property_read_u32(dev, "snps,data-width", &tmp);
1403 	if (ret)
1404 		return ret;
1405 	if (tmp > DWAXIDMAC_TRANS_WIDTH_MAX)
1406 		return -EINVAL;
1407 
1408 	chip->dw->hdata->m_data_width = tmp;
1409 
1410 	ret = device_property_read_u32_array(dev, "snps,block-size", carr,
1411 					     chip->dw->hdata->nr_channels);
1412 	if (ret)
1413 		return ret;
1414 	for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
1415 		if (carr[tmp] == 0 || carr[tmp] > DMAC_MAX_BLK_SIZE)
1416 			return -EINVAL;
1417 
1418 		chip->dw->hdata->block_size[tmp] = carr[tmp];
1419 	}
1420 
1421 	ret = device_property_read_u32_array(dev, "snps,priority", carr,
1422 					     chip->dw->hdata->nr_channels);
1423 	if (ret)
1424 		return ret;
1425 	/* Priority value must be programmed within [0:nr_channels-1] range */
1426 	for (tmp = 0; tmp < chip->dw->hdata->nr_channels; tmp++) {
1427 		if (carr[tmp] >= chip->dw->hdata->nr_channels)
1428 			return -EINVAL;
1429 
1430 		chip->dw->hdata->priority[tmp] = carr[tmp];
1431 	}
1432 
1433 	/* axi-max-burst-len is optional property */
1434 	ret = device_property_read_u32(dev, "snps,axi-max-burst-len", &tmp);
1435 	if (!ret) {
1436 		if (tmp > DWAXIDMAC_ARWLEN_MAX + 1)
1437 			return -EINVAL;
1438 		if (tmp < DWAXIDMAC_ARWLEN_MIN + 1)
1439 			return -EINVAL;
1440 
1441 		chip->dw->hdata->restrict_axi_burst_len = true;
1442 		chip->dw->hdata->axi_rw_burst_len = tmp;
1443 	}
1444 
1445 	return 0;
1446 }
1447 
1448 static int dw_probe(struct platform_device *pdev)
1449 {
1450 	struct axi_dma_chip *chip;
1451 	struct dw_axi_dma *dw;
1452 	struct dw_axi_dma_hcfg *hdata;
1453 	struct reset_control *resets;
1454 	unsigned int flags;
1455 	u32 i;
1456 	int ret;
1457 
1458 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
1459 	if (!chip)
1460 		return -ENOMEM;
1461 
1462 	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
1463 	if (!dw)
1464 		return -ENOMEM;
1465 
1466 	hdata = devm_kzalloc(&pdev->dev, sizeof(*hdata), GFP_KERNEL);
1467 	if (!hdata)
1468 		return -ENOMEM;
1469 
1470 	chip->dw = dw;
1471 	chip->dev = &pdev->dev;
1472 	chip->dw->hdata = hdata;
1473 
1474 	chip->irq = platform_get_irq(pdev, 0);
1475 	if (chip->irq < 0)
1476 		return chip->irq;
1477 
1478 	chip->regs = devm_platform_ioremap_resource(pdev, 0);
1479 	if (IS_ERR(chip->regs))
1480 		return PTR_ERR(chip->regs);
1481 
1482 	flags = (uintptr_t)of_device_get_match_data(&pdev->dev);
1483 	if (flags & AXI_DMA_FLAG_HAS_APB_REGS) {
1484 		chip->apb_regs = devm_platform_ioremap_resource(pdev, 1);
1485 		if (IS_ERR(chip->apb_regs))
1486 			return PTR_ERR(chip->apb_regs);
1487 	}
1488 
1489 	if (flags & AXI_DMA_FLAG_HAS_RESETS) {
1490 		resets = devm_reset_control_array_get_exclusive(&pdev->dev);
1491 		if (IS_ERR(resets))
1492 			return PTR_ERR(resets);
1493 
1494 		ret = reset_control_deassert(resets);
1495 		if (ret)
1496 			return ret;
1497 	}
1498 
1499 	chip->dw->hdata->use_cfg2 = !!(flags & AXI_DMA_FLAG_USE_CFG2);
1500 
1501 	chip->core_clk = devm_clk_get(chip->dev, "core-clk");
1502 	if (IS_ERR(chip->core_clk))
1503 		return PTR_ERR(chip->core_clk);
1504 
1505 	chip->cfgr_clk = devm_clk_get(chip->dev, "cfgr-clk");
1506 	if (IS_ERR(chip->cfgr_clk))
1507 		return PTR_ERR(chip->cfgr_clk);
1508 
1509 	ret = parse_device_properties(chip);
1510 	if (ret)
1511 		return ret;
1512 
1513 	dw->chan = devm_kcalloc(chip->dev, hdata->nr_channels,
1514 				sizeof(*dw->chan), GFP_KERNEL);
1515 	if (!dw->chan)
1516 		return -ENOMEM;
1517 
1518 	ret = devm_request_irq(chip->dev, chip->irq, dw_axi_dma_interrupt,
1519 			       IRQF_SHARED, KBUILD_MODNAME, chip);
1520 	if (ret)
1521 		return ret;
1522 
1523 	INIT_LIST_HEAD(&dw->dma.channels);
1524 	for (i = 0; i < hdata->nr_channels; i++) {
1525 		struct axi_dma_chan *chan = &dw->chan[i];
1526 
1527 		chan->chip = chip;
1528 		chan->id = i;
1529 		chan->chan_regs = chip->regs + COMMON_REG_LEN + i * CHAN_REG_LEN;
1530 		atomic_set(&chan->descs_allocated, 0);
1531 
1532 		chan->vc.desc_free = vchan_desc_put;
1533 		vchan_init(&chan->vc, &dw->dma);
1534 	}
1535 
1536 	/* Set capabilities */
1537 	dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
1538 	dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
1539 	dma_cap_set(DMA_CYCLIC, dw->dma.cap_mask);
1540 
1541 	/* DMA capabilities */
1542 	dw->dma.max_burst = hdata->axi_rw_burst_len;
1543 	dw->dma.src_addr_widths = AXI_DMA_BUSWIDTHS;
1544 	dw->dma.dst_addr_widths = AXI_DMA_BUSWIDTHS;
1545 	dw->dma.directions = BIT(DMA_MEM_TO_MEM);
1546 	dw->dma.directions |= BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
1547 	dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1548 
1549 	dw->dma.dev = chip->dev;
1550 	dw->dma.device_tx_status = dma_chan_tx_status;
1551 	dw->dma.device_issue_pending = dma_chan_issue_pending;
1552 	dw->dma.device_terminate_all = dma_chan_terminate_all;
1553 	dw->dma.device_pause = dma_chan_pause;
1554 	dw->dma.device_resume = dma_chan_resume;
1555 
1556 	dw->dma.device_alloc_chan_resources = dma_chan_alloc_chan_resources;
1557 	dw->dma.device_free_chan_resources = dma_chan_free_chan_resources;
1558 
1559 	dw->dma.device_prep_dma_memcpy = dma_chan_prep_dma_memcpy;
1560 	dw->dma.device_synchronize = dw_axi_dma_synchronize;
1561 	dw->dma.device_config = dw_axi_dma_chan_slave_config;
1562 	dw->dma.device_prep_slave_sg = dw_axi_dma_chan_prep_slave_sg;
1563 	dw->dma.device_prep_dma_cyclic = dw_axi_dma_chan_prep_cyclic;
1564 
1565 	/*
1566 	 * Synopsis DesignWare AxiDMA datasheet mentioned Maximum
1567 	 * supported blocks is 1024. Device register width is 4 bytes.
1568 	 * Therefore, set constraint to 1024 * 4.
1569 	 */
1570 	dw->dma.dev->dma_parms = &dw->dma_parms;
1571 	dma_set_max_seg_size(&pdev->dev, MAX_BLOCK_SIZE);
1572 	platform_set_drvdata(pdev, chip);
1573 
1574 	pm_runtime_enable(chip->dev);
1575 
1576 	/*
1577 	 * We can't just call pm_runtime_get here instead of
1578 	 * pm_runtime_get_noresume + axi_dma_resume because we need
1579 	 * driver to work also without Runtime PM.
1580 	 */
1581 	pm_runtime_get_noresume(chip->dev);
1582 	ret = axi_dma_resume(chip);
1583 	if (ret < 0)
1584 		goto err_pm_disable;
1585 
1586 	axi_dma_hw_init(chip);
1587 
1588 	pm_runtime_put(chip->dev);
1589 
1590 	ret = dmaenginem_async_device_register(&dw->dma);
1591 	if (ret)
1592 		goto err_pm_disable;
1593 
1594 	/* Register with OF helpers for DMA lookups */
1595 	ret = of_dma_controller_register(pdev->dev.of_node,
1596 					 dw_axi_dma_of_xlate, dw);
1597 	if (ret < 0)
1598 		dev_warn(&pdev->dev,
1599 			 "Failed to register OF DMA controller, fallback to MEM_TO_MEM mode\n");
1600 
1601 	dev_info(chip->dev, "DesignWare AXI DMA Controller, %d channels\n",
1602 		 dw->hdata->nr_channels);
1603 
1604 	return 0;
1605 
1606 err_pm_disable:
1607 	pm_runtime_disable(chip->dev);
1608 
1609 	return ret;
1610 }
1611 
1612 static void dw_remove(struct platform_device *pdev)
1613 {
1614 	struct axi_dma_chip *chip = platform_get_drvdata(pdev);
1615 	struct dw_axi_dma *dw = chip->dw;
1616 	struct axi_dma_chan *chan, *_chan;
1617 	u32 i;
1618 
1619 	/* Enable clk before accessing to registers */
1620 	clk_prepare_enable(chip->cfgr_clk);
1621 	clk_prepare_enable(chip->core_clk);
1622 	axi_dma_irq_disable(chip);
1623 	for (i = 0; i < dw->hdata->nr_channels; i++) {
1624 		axi_chan_disable(&chip->dw->chan[i]);
1625 		axi_chan_irq_disable(&chip->dw->chan[i], DWAXIDMAC_IRQ_ALL);
1626 	}
1627 	axi_dma_disable(chip);
1628 
1629 	pm_runtime_disable(chip->dev);
1630 	axi_dma_suspend(chip);
1631 
1632 	devm_free_irq(chip->dev, chip->irq, chip);
1633 
1634 	of_dma_controller_free(chip->dev->of_node);
1635 
1636 	list_for_each_entry_safe(chan, _chan, &dw->dma.channels,
1637 			vc.chan.device_node) {
1638 		list_del(&chan->vc.chan.device_node);
1639 		tasklet_kill(&chan->vc.task);
1640 	}
1641 }
1642 
1643 static const struct dev_pm_ops dw_axi_dma_pm_ops = {
1644 	SET_RUNTIME_PM_OPS(axi_dma_runtime_suspend, axi_dma_runtime_resume, NULL)
1645 };
1646 
1647 static const struct of_device_id dw_dma_of_id_table[] = {
1648 	{
1649 		.compatible = "snps,axi-dma-1.01a"
1650 	}, {
1651 		.compatible = "intel,kmb-axi-dma",
1652 		.data = (void *)AXI_DMA_FLAG_HAS_APB_REGS,
1653 	}, {
1654 		.compatible = "starfive,jh7110-axi-dma",
1655 		.data = (void *)(AXI_DMA_FLAG_HAS_RESETS | AXI_DMA_FLAG_USE_CFG2),
1656 	},
1657 	{}
1658 };
1659 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
1660 
1661 static struct platform_driver dw_driver = {
1662 	.probe		= dw_probe,
1663 	.remove_new	= dw_remove,
1664 	.driver = {
1665 		.name	= KBUILD_MODNAME,
1666 		.of_match_table = dw_dma_of_id_table,
1667 		.pm = &dw_axi_dma_pm_ops,
1668 	},
1669 };
1670 module_platform_driver(dw_driver);
1671 
1672 MODULE_LICENSE("GPL v2");
1673 MODULE_DESCRIPTION("Synopsys DesignWare AXI DMA Controller platform driver");
1674 MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
1675