xref: /linux/drivers/dma/fsl-edma-main.c (revision 9ab27b018649c9504e894496cb4d7d8afcffd897)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * drivers/dma/fsl-edma.c
4  *
5  * Copyright 2013-2014 Freescale Semiconductor, Inc.
6  *
7  * Driver for the Freescale eDMA engine with flexible channel multiplexing
8  * capability for DMA request sources. The eDMA block can be found on some
9  * Vybrid and Layerscape SoCs.
10  */
11 
12 #include <dt-bindings/dma/fsl-edma.h>
13 #include <linux/bitfield.h>
14 #include <linux/module.h>
15 #include <linux/interrupt.h>
16 #include <linux/clk.h>
17 #include <linux/of.h>
18 #include <linux/of_dma.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/pm_domain.h>
22 #include <linux/property.h>
23 
24 #include "fsl-edma-common.h"
25 
26 static void fsl_edma_synchronize(struct dma_chan *chan)
27 {
28 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
29 
30 	vchan_synchronize(&fsl_chan->vchan);
31 }
32 
33 static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
34 {
35 	struct fsl_edma_engine *fsl_edma = dev_id;
36 	unsigned int intr, ch;
37 	struct edma_regs *regs = &fsl_edma->regs;
38 
39 	intr = edma_readl(fsl_edma, regs->intl);
40 	if (!intr)
41 		return IRQ_NONE;
42 
43 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
44 		if (intr & (0x1 << ch)) {
45 			edma_writeb(fsl_edma, EDMA_CINT_CINT(ch), regs->cint);
46 			fsl_edma_tx_chan_handler(&fsl_edma->chans[ch]);
47 		}
48 	}
49 	return IRQ_HANDLED;
50 }
51 
52 static irqreturn_t fsl_edma3_tx_handler(int irq, void *dev_id)
53 {
54 	struct fsl_edma_chan *fsl_chan = dev_id;
55 	unsigned int intr;
56 
57 	intr = edma_readl_chreg(fsl_chan, ch_int);
58 	if (!intr)
59 		return IRQ_HANDLED;
60 
61 	edma_writel_chreg(fsl_chan, 1, ch_int);
62 
63 	fsl_edma_tx_chan_handler(fsl_chan);
64 
65 	return IRQ_HANDLED;
66 }
67 
68 static irqreturn_t fsl_edma2_tx_handler(int irq, void *devi_id)
69 {
70 	struct fsl_edma_chan *fsl_chan = devi_id;
71 
72 	return fsl_edma_tx_handler(irq, fsl_chan->edma);
73 }
74 
75 static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
76 {
77 	struct fsl_edma_engine *fsl_edma = dev_id;
78 	unsigned int err, ch;
79 	struct edma_regs *regs = &fsl_edma->regs;
80 
81 	err = edma_readl(fsl_edma, regs->errl);
82 	if (!err)
83 		return IRQ_NONE;
84 
85 	for (ch = 0; ch < fsl_edma->n_chans; ch++) {
86 		if (err & (0x1 << ch)) {
87 			fsl_edma_disable_request(&fsl_edma->chans[ch]);
88 			edma_writeb(fsl_edma, EDMA_CERR_CERR(ch), regs->cerr);
89 			fsl_edma_err_chan_handler(&fsl_edma->chans[ch]);
90 		}
91 	}
92 	return IRQ_HANDLED;
93 }
94 
95 static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
96 {
97 	if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
98 		return IRQ_HANDLED;
99 
100 	return fsl_edma_err_handler(irq, dev_id);
101 }
102 
103 static bool fsl_edma_srcid_in_use(struct fsl_edma_engine *fsl_edma, u32 srcid)
104 {
105 	struct fsl_edma_chan *fsl_chan;
106 	int i;
107 
108 	for (i = 0; i < fsl_edma->n_chans; i++) {
109 		fsl_chan = &fsl_edma->chans[i];
110 
111 		if (fsl_chan->srcid && srcid == fsl_chan->srcid) {
112 			dev_err(&fsl_chan->pdev->dev, "The srcid is in use, can't use!");
113 			return true;
114 		}
115 	}
116 	return false;
117 }
118 
119 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
120 		struct of_dma *ofdma)
121 {
122 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
123 	struct dma_chan *chan, *_chan;
124 	struct fsl_edma_chan *fsl_chan;
125 	u32 dmamux_nr = fsl_edma->drvdata->dmamuxs;
126 	unsigned long chans_per_mux = fsl_edma->n_chans / dmamux_nr;
127 
128 	if (dma_spec->args_count != 2)
129 		return NULL;
130 
131 	guard(mutex)(&fsl_edma->fsl_edma_mutex);
132 
133 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
134 		if (chan->client_count)
135 			continue;
136 
137 		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[1]))
138 			return NULL;
139 
140 		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
141 			chan = dma_get_slave_channel(chan);
142 			if (chan) {
143 				chan->device->privatecnt++;
144 				fsl_chan = to_fsl_edma_chan(chan);
145 				fsl_chan->srcid = dma_spec->args[1];
146 
147 				if (!fsl_chan->srcid) {
148 					dev_err(&fsl_chan->pdev->dev, "Invalidate srcid %d\n",
149 						fsl_chan->srcid);
150 					return NULL;
151 				}
152 
153 				fsl_edma_chan_mux(fsl_chan, fsl_chan->srcid,
154 						true);
155 				return chan;
156 			}
157 		}
158 	}
159 	return NULL;
160 }
161 
162 static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
163 					struct of_dma *ofdma)
164 {
165 	struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
166 	struct dma_chan *chan, *_chan;
167 	struct fsl_edma_chan *fsl_chan;
168 	bool b_chmux;
169 	int i;
170 
171 	if (dma_spec->args_count != 3)
172 		return NULL;
173 
174 	b_chmux = !!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHMUX);
175 
176 	guard(mutex)(&fsl_edma->fsl_edma_mutex);
177 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels,
178 					device_node) {
179 
180 		if (chan->client_count)
181 			continue;
182 
183 		fsl_chan = to_fsl_edma_chan(chan);
184 		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[0]))
185 			return NULL;
186 		i = fsl_chan - fsl_edma->chans;
187 
188 		fsl_chan->priority = dma_spec->args[1];
189 		fsl_chan->is_rxchan = dma_spec->args[2] & FSL_EDMA_RX;
190 		fsl_chan->is_remote = dma_spec->args[2] & FSL_EDMA_REMOTE;
191 		fsl_chan->is_multi_fifo = dma_spec->args[2] & FSL_EDMA_MULTI_FIFO;
192 
193 		if ((dma_spec->args[2] & FSL_EDMA_EVEN_CH) && (i & 0x1))
194 			continue;
195 
196 		if ((dma_spec->args[2] & FSL_EDMA_ODD_CH) && !(i & 0x1))
197 			continue;
198 
199 		if (!b_chmux && i == dma_spec->args[0]) {
200 			chan = dma_get_slave_channel(chan);
201 			chan->device->privatecnt++;
202 			return chan;
203 		} else if (b_chmux && !fsl_chan->srcid) {
204 			/* if controller support channel mux, choose a free channel */
205 			chan = dma_get_slave_channel(chan);
206 			chan->device->privatecnt++;
207 			fsl_chan->srcid = dma_spec->args[0];
208 			return chan;
209 		}
210 	}
211 	return NULL;
212 }
213 
214 static int
215 fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
216 {
217 	int ret;
218 
219 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
220 
221 	fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
222 	if (fsl_edma->txirq < 0)
223 		return fsl_edma->txirq;
224 
225 	fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
226 	if (fsl_edma->errirq < 0)
227 		return fsl_edma->errirq;
228 
229 	if (fsl_edma->txirq == fsl_edma->errirq) {
230 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
231 				fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
232 		if (ret) {
233 			dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
234 			return ret;
235 		}
236 	} else {
237 		ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
238 				fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
239 		if (ret) {
240 			dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
241 			return ret;
242 		}
243 
244 		ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
245 				fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
246 		if (ret) {
247 			dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
248 			return ret;
249 		}
250 	}
251 
252 	return 0;
253 }
254 
255 static int fsl_edma3_irq_init(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
256 {
257 	int i;
258 
259 	for (i = 0; i < fsl_edma->n_chans; i++) {
260 
261 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
262 
263 		if (fsl_edma->chan_masked & BIT(i))
264 			continue;
265 
266 		/* request channel irq */
267 		fsl_chan->txirq = platform_get_irq(pdev, i);
268 		if (fsl_chan->txirq < 0)
269 			return  -EINVAL;
270 
271 		fsl_chan->irq_handler = fsl_edma3_tx_handler;
272 	}
273 
274 	return 0;
275 }
276 
277 static int
278 fsl_edma2_irq_init(struct platform_device *pdev,
279 		   struct fsl_edma_engine *fsl_edma)
280 {
281 	int i, ret, irq;
282 	int count;
283 
284 	edma_writel(fsl_edma, ~0, fsl_edma->regs.intl);
285 
286 	count = platform_irq_count(pdev);
287 	dev_dbg(&pdev->dev, "%s Found %d interrupts\r\n", __func__, count);
288 	if (count <= 2) {
289 		dev_err(&pdev->dev, "Interrupts in DTS not correct.\n");
290 		return -EINVAL;
291 	}
292 	/*
293 	 * 16 channel independent interrupts + 1 error interrupt on i.mx7ulp.
294 	 * 2 channel share one interrupt, for example, ch0/ch16, ch1/ch17...
295 	 * For now, just simply request irq without IRQF_SHARED flag, since 16
296 	 * channels are enough on i.mx7ulp whose M4 domain own some peripherals.
297 	 */
298 	for (i = 0; i < count; i++) {
299 		irq = platform_get_irq(pdev, i);
300 		ret = 0;
301 		if (irq < 0)
302 			return -ENXIO;
303 
304 		/* The last IRQ is for eDMA err */
305 		if (i == count - 1) {
306 			ret = devm_request_irq(&pdev->dev, irq,
307 						fsl_edma_err_handler,
308 						0, "eDMA2-ERR", fsl_edma);
309 		} else {
310 			fsl_edma->chans[i].txirq = irq;
311 			fsl_edma->chans[i].irq_handler = fsl_edma2_tx_handler;
312 		}
313 
314 		if (ret)
315 			return ret;
316 	}
317 
318 	return 0;
319 }
320 
321 static void fsl_edma_irq_exit(
322 		struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
323 {
324 	if (fsl_edma->txirq == fsl_edma->errirq) {
325 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
326 	} else {
327 		devm_free_irq(&pdev->dev, fsl_edma->txirq, fsl_edma);
328 		devm_free_irq(&pdev->dev, fsl_edma->errirq, fsl_edma);
329 	}
330 }
331 
332 static void fsl_disable_clocks(struct fsl_edma_engine *fsl_edma, int nr_clocks)
333 {
334 	int i;
335 
336 	for (i = 0; i < nr_clocks; i++)
337 		clk_disable_unprepare(fsl_edma->muxclk[i]);
338 }
339 
340 static struct fsl_edma_drvdata vf610_data = {
341 	.dmamuxs = DMAMUX_NR,
342 	.flags = FSL_EDMA_DRV_WRAP_IO,
343 	.chreg_off = EDMA_TCD,
344 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
345 	.setup_irq = fsl_edma_irq_init,
346 };
347 
348 static struct fsl_edma_drvdata ls1028a_data = {
349 	.dmamuxs = DMAMUX_NR,
350 	.flags = FSL_EDMA_DRV_MUX_SWAP | FSL_EDMA_DRV_WRAP_IO,
351 	.chreg_off = EDMA_TCD,
352 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
353 	.setup_irq = fsl_edma_irq_init,
354 };
355 
356 static struct fsl_edma_drvdata imx7ulp_data = {
357 	.dmamuxs = 1,
358 	.chreg_off = EDMA_TCD,
359 	.chreg_space_sz = sizeof(struct fsl_edma_hw_tcd),
360 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_CONFIG32,
361 	.setup_irq = fsl_edma2_irq_init,
362 };
363 
364 static struct fsl_edma_drvdata imx8qm_data = {
365 	.flags = FSL_EDMA_DRV_HAS_PD | FSL_EDMA_DRV_EDMA3 | FSL_EDMA_DRV_MEM_REMOTE,
366 	.chreg_space_sz = 0x10000,
367 	.chreg_off = 0x10000,
368 	.setup_irq = fsl_edma3_irq_init,
369 };
370 
371 static struct fsl_edma_drvdata imx8ulp_data = {
372 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_CHCLK | FSL_EDMA_DRV_HAS_DMACLK |
373 		 FSL_EDMA_DRV_EDMA3,
374 	.chreg_space_sz = 0x10000,
375 	.chreg_off = 0x10000,
376 	.mux_off = 0x10000 + offsetof(struct fsl_edma3_ch_reg, ch_mux),
377 	.mux_skip = 0x10000,
378 	.setup_irq = fsl_edma3_irq_init,
379 };
380 
381 static struct fsl_edma_drvdata imx93_data3 = {
382 	.flags = FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA3,
383 	.chreg_space_sz = 0x10000,
384 	.chreg_off = 0x10000,
385 	.setup_irq = fsl_edma3_irq_init,
386 };
387 
388 static struct fsl_edma_drvdata imx93_data4 = {
389 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA4,
390 	.chreg_space_sz = 0x8000,
391 	.chreg_off = 0x10000,
392 	.mux_off = 0x10000 + offsetof(struct fsl_edma3_ch_reg, ch_mux),
393 	.mux_skip = 0x8000,
394 	.setup_irq = fsl_edma3_irq_init,
395 };
396 
397 static struct fsl_edma_drvdata imx95_data5 = {
398 	.flags = FSL_EDMA_DRV_HAS_CHMUX | FSL_EDMA_DRV_HAS_DMACLK | FSL_EDMA_DRV_EDMA4 |
399 		 FSL_EDMA_DRV_TCD64,
400 	.chreg_space_sz = 0x8000,
401 	.chreg_off = 0x10000,
402 	.mux_off = 0x200,
403 	.mux_skip = sizeof(u32),
404 	.setup_irq = fsl_edma3_irq_init,
405 };
406 
407 static const struct of_device_id fsl_edma_dt_ids[] = {
408 	{ .compatible = "fsl,vf610-edma", .data = &vf610_data},
409 	{ .compatible = "fsl,ls1028a-edma", .data = &ls1028a_data},
410 	{ .compatible = "fsl,imx7ulp-edma", .data = &imx7ulp_data},
411 	{ .compatible = "fsl,imx8qm-edma", .data = &imx8qm_data},
412 	{ .compatible = "fsl,imx8ulp-edma", .data = &imx8ulp_data},
413 	{ .compatible = "fsl,imx93-edma3", .data = &imx93_data3},
414 	{ .compatible = "fsl,imx93-edma4", .data = &imx93_data4},
415 	{ .compatible = "fsl,imx95-edma5", .data = &imx95_data5},
416 	{ /* sentinel */ }
417 };
418 MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
419 
420 static int fsl_edma3_attach_pd(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
421 {
422 	struct fsl_edma_chan *fsl_chan;
423 	struct device_link *link;
424 	struct device *pd_chan;
425 	struct device *dev;
426 	int i;
427 
428 	dev = &pdev->dev;
429 
430 	for (i = 0; i < fsl_edma->n_chans; i++) {
431 		if (fsl_edma->chan_masked & BIT(i))
432 			continue;
433 
434 		fsl_chan = &fsl_edma->chans[i];
435 
436 		pd_chan = dev_pm_domain_attach_by_id(dev, i);
437 		if (IS_ERR_OR_NULL(pd_chan)) {
438 			dev_err(dev, "Failed attach pd %d\n", i);
439 			return -EINVAL;
440 		}
441 
442 		link = device_link_add(dev, pd_chan, DL_FLAG_STATELESS |
443 					     DL_FLAG_PM_RUNTIME |
444 					     DL_FLAG_RPM_ACTIVE);
445 		if (!link) {
446 			dev_err(dev, "Failed to add device_link to %d\n", i);
447 			return -EINVAL;
448 		}
449 
450 		fsl_chan->pd_dev = pd_chan;
451 
452 		pm_runtime_use_autosuspend(fsl_chan->pd_dev);
453 		pm_runtime_set_autosuspend_delay(fsl_chan->pd_dev, 200);
454 		pm_runtime_set_active(fsl_chan->pd_dev);
455 	}
456 
457 	return 0;
458 }
459 
460 static int fsl_edma_probe(struct platform_device *pdev)
461 {
462 	struct device_node *np = pdev->dev.of_node;
463 	struct fsl_edma_engine *fsl_edma;
464 	const struct fsl_edma_drvdata *drvdata = NULL;
465 	u32 chan_mask[2] = {0, 0};
466 	char clk_name[36];
467 	struct edma_regs *regs;
468 	int chans;
469 	int ret, i;
470 
471 	drvdata = device_get_match_data(&pdev->dev);
472 	if (!drvdata) {
473 		dev_err(&pdev->dev, "unable to find driver data\n");
474 		return -EINVAL;
475 	}
476 
477 	ret = of_property_read_u32(np, "dma-channels", &chans);
478 	if (ret) {
479 		dev_err(&pdev->dev, "Can't get dma-channels.\n");
480 		return ret;
481 	}
482 
483 	fsl_edma = devm_kzalloc(&pdev->dev, struct_size(fsl_edma, chans, chans),
484 				GFP_KERNEL);
485 	if (!fsl_edma)
486 		return -ENOMEM;
487 
488 	fsl_edma->drvdata = drvdata;
489 	fsl_edma->n_chans = chans;
490 	mutex_init(&fsl_edma->fsl_edma_mutex);
491 
492 	fsl_edma->membase = devm_platform_ioremap_resource(pdev, 0);
493 	if (IS_ERR(fsl_edma->membase))
494 		return PTR_ERR(fsl_edma->membase);
495 
496 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)) {
497 		fsl_edma_setup_regs(fsl_edma);
498 		regs = &fsl_edma->regs;
499 	}
500 
501 	if (drvdata->flags & FSL_EDMA_DRV_HAS_DMACLK) {
502 		fsl_edma->dmaclk = devm_clk_get_enabled(&pdev->dev, "dma");
503 		if (IS_ERR(fsl_edma->dmaclk)) {
504 			dev_err(&pdev->dev, "Missing DMA block clock.\n");
505 			return PTR_ERR(fsl_edma->dmaclk);
506 		}
507 	}
508 
509 	ret = of_property_read_variable_u32_array(np, "dma-channel-mask", chan_mask, 1, 2);
510 
511 	if (ret > 0) {
512 		fsl_edma->chan_masked = chan_mask[1];
513 		fsl_edma->chan_masked <<= 32;
514 		fsl_edma->chan_masked |= chan_mask[0];
515 	}
516 
517 	for (i = 0; i < fsl_edma->drvdata->dmamuxs; i++) {
518 		char clkname[32];
519 
520 		/* eDMAv3 mux register move to TCD area if ch_mux exist */
521 		if (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG)
522 			break;
523 
524 		fsl_edma->muxbase[i] = devm_platform_ioremap_resource(pdev,
525 								      1 + i);
526 		if (IS_ERR(fsl_edma->muxbase[i])) {
527 			/* on error: disable all previously enabled clks */
528 			fsl_disable_clocks(fsl_edma, i);
529 			return PTR_ERR(fsl_edma->muxbase[i]);
530 		}
531 
532 		sprintf(clkname, "dmamux%d", i);
533 		fsl_edma->muxclk[i] = devm_clk_get_enabled(&pdev->dev, clkname);
534 		if (IS_ERR(fsl_edma->muxclk[i])) {
535 			dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
536 			/* on error: disable all previously enabled clks */
537 			return PTR_ERR(fsl_edma->muxclk[i]);
538 		}
539 	}
540 
541 	fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
542 
543 	if (drvdata->flags & FSL_EDMA_DRV_HAS_PD) {
544 		ret = fsl_edma3_attach_pd(pdev, fsl_edma);
545 		if (ret)
546 			return ret;
547 	}
548 
549 	if (drvdata->flags & FSL_EDMA_DRV_TCD64)
550 		dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
551 
552 	INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
553 	for (i = 0; i < fsl_edma->n_chans; i++) {
554 		struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
555 		int len;
556 
557 		if (fsl_edma->chan_masked & BIT(i))
558 			continue;
559 
560 		snprintf(fsl_chan->chan_name, sizeof(fsl_chan->chan_name), "%s-CH%02d",
561 							   dev_name(&pdev->dev), i);
562 
563 		fsl_chan->edma = fsl_edma;
564 		fsl_chan->pm_state = RUNNING;
565 		fsl_chan->srcid = 0;
566 		fsl_chan->dma_dir = DMA_NONE;
567 		fsl_chan->vchan.desc_free = fsl_edma_free_desc;
568 
569 		len = (drvdata->flags & FSL_EDMA_DRV_SPLIT_REG) ?
570 				offsetof(struct fsl_edma3_ch_reg, tcd) : 0;
571 		fsl_chan->tcd = fsl_edma->membase
572 				+ i * drvdata->chreg_space_sz + drvdata->chreg_off + len;
573 		fsl_chan->mux_addr = fsl_edma->membase + drvdata->mux_off + i * drvdata->mux_skip;
574 
575 		if (drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK) {
576 			snprintf(clk_name, sizeof(clk_name), "ch%02d", i);
577 			fsl_chan->clk = devm_clk_get_enabled(&pdev->dev,
578 							     (const char *)clk_name);
579 
580 			if (IS_ERR(fsl_chan->clk))
581 				return PTR_ERR(fsl_chan->clk);
582 		}
583 		fsl_chan->pdev = pdev;
584 		vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
585 
586 		edma_write_tcdreg(fsl_chan, cpu_to_le32(0), csr);
587 		fsl_edma_chan_mux(fsl_chan, 0, false);
588 		if (fsl_chan->edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHCLK)
589 			clk_disable_unprepare(fsl_chan->clk);
590 	}
591 
592 	ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
593 	if (ret)
594 		return ret;
595 
596 	dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
597 	dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
598 	dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
599 	dma_cap_set(DMA_MEMCPY, fsl_edma->dma_dev.cap_mask);
600 
601 	fsl_edma->dma_dev.dev = &pdev->dev;
602 	fsl_edma->dma_dev.device_alloc_chan_resources
603 		= fsl_edma_alloc_chan_resources;
604 	fsl_edma->dma_dev.device_free_chan_resources
605 		= fsl_edma_free_chan_resources;
606 	fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
607 	fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
608 	fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
609 	fsl_edma->dma_dev.device_prep_dma_memcpy = fsl_edma_prep_memcpy;
610 	fsl_edma->dma_dev.device_config = fsl_edma_slave_config;
611 	fsl_edma->dma_dev.device_pause = fsl_edma_pause;
612 	fsl_edma->dma_dev.device_resume = fsl_edma_resume;
613 	fsl_edma->dma_dev.device_terminate_all = fsl_edma_terminate_all;
614 	fsl_edma->dma_dev.device_synchronize = fsl_edma_synchronize;
615 	fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
616 
617 	fsl_edma->dma_dev.src_addr_widths = FSL_EDMA_BUSWIDTHS;
618 	fsl_edma->dma_dev.dst_addr_widths = FSL_EDMA_BUSWIDTHS;
619 
620 	if (drvdata->flags & FSL_EDMA_DRV_BUS_8BYTE) {
621 		fsl_edma->dma_dev.src_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
622 		fsl_edma->dma_dev.dst_addr_widths |= BIT(DMA_SLAVE_BUSWIDTH_8_BYTES);
623 	}
624 
625 	fsl_edma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
626 	if (drvdata->flags & FSL_EDMA_DRV_DEV_TO_DEV)
627 		fsl_edma->dma_dev.directions |= BIT(DMA_DEV_TO_DEV);
628 
629 	fsl_edma->dma_dev.copy_align = drvdata->flags & FSL_EDMA_DRV_ALIGN_64BYTE ?
630 					DMAENGINE_ALIGN_64_BYTES :
631 					DMAENGINE_ALIGN_32_BYTES;
632 
633 	/* Per worst case 'nbytes = 1' take CITER as the max_seg_size */
634 	dma_set_max_seg_size(fsl_edma->dma_dev.dev,
635 			     FIELD_GET(EDMA_TCD_ITER_MASK, EDMA_TCD_ITER_MASK));
636 
637 	fsl_edma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
638 
639 	platform_set_drvdata(pdev, fsl_edma);
640 
641 	ret = dma_async_device_register(&fsl_edma->dma_dev);
642 	if (ret) {
643 		dev_err(&pdev->dev,
644 			"Can't register Freescale eDMA engine. (%d)\n", ret);
645 		return ret;
646 	}
647 
648 	ret = of_dma_controller_register(np,
649 			drvdata->flags & FSL_EDMA_DRV_SPLIT_REG ? fsl_edma3_xlate : fsl_edma_xlate,
650 			fsl_edma);
651 	if (ret) {
652 		dev_err(&pdev->dev,
653 			"Can't register Freescale eDMA of_dma. (%d)\n", ret);
654 		dma_async_device_unregister(&fsl_edma->dma_dev);
655 		return ret;
656 	}
657 
658 	/* enable round robin arbitration */
659 	if (!(drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
660 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
661 
662 	return 0;
663 }
664 
665 static void fsl_edma_remove(struct platform_device *pdev)
666 {
667 	struct device_node *np = pdev->dev.of_node;
668 	struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
669 
670 	fsl_edma_irq_exit(pdev, fsl_edma);
671 	fsl_edma_cleanup_vchan(&fsl_edma->dma_dev);
672 	of_dma_controller_free(np);
673 	dma_async_device_unregister(&fsl_edma->dma_dev);
674 	fsl_disable_clocks(fsl_edma, fsl_edma->drvdata->dmamuxs);
675 }
676 
677 static int fsl_edma_suspend_late(struct device *dev)
678 {
679 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
680 	struct fsl_edma_chan *fsl_chan;
681 	unsigned long flags;
682 	int i;
683 
684 	for (i = 0; i < fsl_edma->n_chans; i++) {
685 		fsl_chan = &fsl_edma->chans[i];
686 		if (fsl_edma->chan_masked & BIT(i))
687 			continue;
688 		spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
689 		/* Make sure chan is idle or will force disable. */
690 		if (unlikely(fsl_chan->status == DMA_IN_PROGRESS)) {
691 			dev_warn(dev, "WARN: There is non-idle channel.");
692 			fsl_edma_disable_request(fsl_chan);
693 			fsl_edma_chan_mux(fsl_chan, 0, false);
694 		}
695 
696 		fsl_chan->pm_state = SUSPENDED;
697 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
698 	}
699 
700 	return 0;
701 }
702 
703 static int fsl_edma_resume_early(struct device *dev)
704 {
705 	struct fsl_edma_engine *fsl_edma = dev_get_drvdata(dev);
706 	struct fsl_edma_chan *fsl_chan;
707 	struct edma_regs *regs = &fsl_edma->regs;
708 	int i;
709 
710 	for (i = 0; i < fsl_edma->n_chans; i++) {
711 		fsl_chan = &fsl_edma->chans[i];
712 		if (fsl_edma->chan_masked & BIT(i))
713 			continue;
714 		fsl_chan->pm_state = RUNNING;
715 		edma_write_tcdreg(fsl_chan, 0, csr);
716 		if (fsl_chan->srcid != 0)
717 			fsl_edma_chan_mux(fsl_chan, fsl_chan->srcid, true);
718 	}
719 
720 	if (!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_SPLIT_REG))
721 		edma_writel(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA, regs->cr);
722 
723 	return 0;
724 }
725 
726 /*
727  * eDMA provides the service to others, so it should be suspend late
728  * and resume early. When eDMA suspend, all of the clients should stop
729  * the DMA data transmission and let the channel idle.
730  */
731 static const struct dev_pm_ops fsl_edma_pm_ops = {
732 	.suspend_late   = fsl_edma_suspend_late,
733 	.resume_early   = fsl_edma_resume_early,
734 };
735 
736 static struct platform_driver fsl_edma_driver = {
737 	.driver		= {
738 		.name	= "fsl-edma",
739 		.of_match_table = fsl_edma_dt_ids,
740 		.pm     = &fsl_edma_pm_ops,
741 	},
742 	.probe          = fsl_edma_probe,
743 	.remove_new	= fsl_edma_remove,
744 };
745 
746 static int __init fsl_edma_init(void)
747 {
748 	return platform_driver_register(&fsl_edma_driver);
749 }
750 subsys_initcall(fsl_edma_init);
751 
752 static void __exit fsl_edma_exit(void)
753 {
754 	platform_driver_unregister(&fsl_edma_driver);
755 }
756 module_exit(fsl_edma_exit);
757 
758 MODULE_ALIAS("platform:fsl-edma");
759 MODULE_DESCRIPTION("Freescale eDMA engine driver");
760 MODULE_LICENSE("GPL v2");
761