xref: /linux/drivers/dma/fsl-edma-common.c (revision db10cb9b)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright (c) 2013-2014 Freescale Semiconductor, Inc
4 // Copyright (c) 2017 Sysam, Angelo Dureghello  <angelo@sysam.it>
5 
6 #include <linux/dmapool.h>
7 #include <linux/module.h>
8 #include <linux/slab.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/pm_runtime.h>
11 #include <linux/pm_domain.h>
12 
13 #include "fsl-edma-common.h"
14 
15 #define EDMA_CR			0x00
16 #define EDMA_ES			0x04
17 #define EDMA_ERQ		0x0C
18 #define EDMA_EEI		0x14
19 #define EDMA_SERQ		0x1B
20 #define EDMA_CERQ		0x1A
21 #define EDMA_SEEI		0x19
22 #define EDMA_CEEI		0x18
23 #define EDMA_CINT		0x1F
24 #define EDMA_CERR		0x1E
25 #define EDMA_SSRT		0x1D
26 #define EDMA_CDNE		0x1C
27 #define EDMA_INTR		0x24
28 #define EDMA_ERR		0x2C
29 
30 #define EDMA64_ERQH		0x08
31 #define EDMA64_EEIH		0x10
32 #define EDMA64_SERQ		0x18
33 #define EDMA64_CERQ		0x19
34 #define EDMA64_SEEI		0x1a
35 #define EDMA64_CEEI		0x1b
36 #define EDMA64_CINT		0x1c
37 #define EDMA64_CERR		0x1d
38 #define EDMA64_SSRT		0x1e
39 #define EDMA64_CDNE		0x1f
40 #define EDMA64_INTH		0x20
41 #define EDMA64_INTL		0x24
42 #define EDMA64_ERRH		0x28
43 #define EDMA64_ERRL		0x2c
44 
45 void fsl_edma_tx_chan_handler(struct fsl_edma_chan *fsl_chan)
46 {
47 	spin_lock(&fsl_chan->vchan.lock);
48 
49 	if (!fsl_chan->edesc) {
50 		/* terminate_all called before */
51 		spin_unlock(&fsl_chan->vchan.lock);
52 		return;
53 	}
54 
55 	if (!fsl_chan->edesc->iscyclic) {
56 		list_del(&fsl_chan->edesc->vdesc.node);
57 		vchan_cookie_complete(&fsl_chan->edesc->vdesc);
58 		fsl_chan->edesc = NULL;
59 		fsl_chan->status = DMA_COMPLETE;
60 		fsl_chan->idle = true;
61 	} else {
62 		vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
63 	}
64 
65 	if (!fsl_chan->edesc)
66 		fsl_edma_xfer_desc(fsl_chan);
67 
68 	spin_unlock(&fsl_chan->vchan.lock);
69 }
70 
71 static void fsl_edma3_enable_request(struct fsl_edma_chan *fsl_chan)
72 {
73 	u32 val, flags;
74 
75 	flags = fsl_edma_drvflags(fsl_chan);
76 	val = edma_readl_chreg(fsl_chan, ch_sbr);
77 	/* Remote/local swapped wrongly on iMX8 QM Audio edma */
78 	if (flags & FSL_EDMA_DRV_QUIRK_SWAPPED) {
79 		if (!fsl_chan->is_rxchan)
80 			val |= EDMA_V3_CH_SBR_RD;
81 		else
82 			val |= EDMA_V3_CH_SBR_WR;
83 	} else {
84 		if (fsl_chan->is_rxchan)
85 			val |= EDMA_V3_CH_SBR_RD;
86 		else
87 			val |= EDMA_V3_CH_SBR_WR;
88 	}
89 
90 	if (fsl_chan->is_remote)
91 		val &= ~(EDMA_V3_CH_SBR_RD | EDMA_V3_CH_SBR_WR);
92 
93 	edma_writel_chreg(fsl_chan, val, ch_sbr);
94 
95 	if (flags & FSL_EDMA_DRV_HAS_CHMUX)
96 		edma_writel_chreg(fsl_chan, fsl_chan->srcid, ch_mux);
97 
98 	val = edma_readl_chreg(fsl_chan, ch_csr);
99 	val |= EDMA_V3_CH_CSR_ERQ;
100 	edma_writel_chreg(fsl_chan, val, ch_csr);
101 }
102 
103 static void fsl_edma_enable_request(struct fsl_edma_chan *fsl_chan)
104 {
105 	struct edma_regs *regs = &fsl_chan->edma->regs;
106 	u32 ch = fsl_chan->vchan.chan.chan_id;
107 
108 	if (fsl_edma_drvflags(fsl_chan) & FSL_EDMA_DRV_SPLIT_REG)
109 		return fsl_edma3_enable_request(fsl_chan);
110 
111 	if (fsl_chan->edma->drvdata->flags & FSL_EDMA_DRV_WRAP_IO) {
112 		edma_writeb(fsl_chan->edma, EDMA_SEEI_SEEI(ch), regs->seei);
113 		edma_writeb(fsl_chan->edma, ch, regs->serq);
114 	} else {
115 		/* ColdFire is big endian, and accesses natively
116 		 * big endian I/O peripherals
117 		 */
118 		iowrite8(EDMA_SEEI_SEEI(ch), regs->seei);
119 		iowrite8(ch, regs->serq);
120 	}
121 }
122 
123 static void fsl_edma3_disable_request(struct fsl_edma_chan *fsl_chan)
124 {
125 	u32 val = edma_readl_chreg(fsl_chan, ch_csr);
126 	u32 flags;
127 
128 	flags = fsl_edma_drvflags(fsl_chan);
129 
130 	if (flags & FSL_EDMA_DRV_HAS_CHMUX)
131 		edma_writel_chreg(fsl_chan, 0, ch_mux);
132 
133 	val &= ~EDMA_V3_CH_CSR_ERQ;
134 	edma_writel_chreg(fsl_chan, val, ch_csr);
135 }
136 
137 void fsl_edma_disable_request(struct fsl_edma_chan *fsl_chan)
138 {
139 	struct edma_regs *regs = &fsl_chan->edma->regs;
140 	u32 ch = fsl_chan->vchan.chan.chan_id;
141 
142 	if (fsl_edma_drvflags(fsl_chan) & FSL_EDMA_DRV_SPLIT_REG)
143 		return fsl_edma3_disable_request(fsl_chan);
144 
145 	if (fsl_chan->edma->drvdata->flags & FSL_EDMA_DRV_WRAP_IO) {
146 		edma_writeb(fsl_chan->edma, ch, regs->cerq);
147 		edma_writeb(fsl_chan->edma, EDMA_CEEI_CEEI(ch), regs->ceei);
148 	} else {
149 		/* ColdFire is big endian, and accesses natively
150 		 * big endian I/O peripherals
151 		 */
152 		iowrite8(ch, regs->cerq);
153 		iowrite8(EDMA_CEEI_CEEI(ch), regs->ceei);
154 	}
155 }
156 
157 static void mux_configure8(struct fsl_edma_chan *fsl_chan, void __iomem *addr,
158 			   u32 off, u32 slot, bool enable)
159 {
160 	u8 val8;
161 
162 	if (enable)
163 		val8 = EDMAMUX_CHCFG_ENBL | slot;
164 	else
165 		val8 = EDMAMUX_CHCFG_DIS;
166 
167 	iowrite8(val8, addr + off);
168 }
169 
170 static void mux_configure32(struct fsl_edma_chan *fsl_chan, void __iomem *addr,
171 			    u32 off, u32 slot, bool enable)
172 {
173 	u32 val;
174 
175 	if (enable)
176 		val = EDMAMUX_CHCFG_ENBL << 24 | slot;
177 	else
178 		val = EDMAMUX_CHCFG_DIS;
179 
180 	iowrite32(val, addr + off * 4);
181 }
182 
183 void fsl_edma_chan_mux(struct fsl_edma_chan *fsl_chan,
184 		       unsigned int slot, bool enable)
185 {
186 	u32 ch = fsl_chan->vchan.chan.chan_id;
187 	void __iomem *muxaddr;
188 	unsigned int chans_per_mux, ch_off;
189 	int endian_diff[4] = {3, 1, -1, -3};
190 	u32 dmamux_nr = fsl_chan->edma->drvdata->dmamuxs;
191 
192 	if (!dmamux_nr)
193 		return;
194 
195 	chans_per_mux = fsl_chan->edma->n_chans / dmamux_nr;
196 	ch_off = fsl_chan->vchan.chan.chan_id % chans_per_mux;
197 
198 	if (fsl_chan->edma->drvdata->flags & FSL_EDMA_DRV_MUX_SWAP)
199 		ch_off += endian_diff[ch_off % 4];
200 
201 	muxaddr = fsl_chan->edma->muxbase[ch / chans_per_mux];
202 	slot = EDMAMUX_CHCFG_SOURCE(slot);
203 
204 	if (fsl_chan->edma->drvdata->flags & FSL_EDMA_DRV_CONFIG32)
205 		mux_configure32(fsl_chan, muxaddr, ch_off, slot, enable);
206 	else
207 		mux_configure8(fsl_chan, muxaddr, ch_off, slot, enable);
208 }
209 
210 static unsigned int fsl_edma_get_tcd_attr(enum dma_slave_buswidth addr_width)
211 {
212 	u32 val;
213 
214 	if (addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
215 		addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
216 
217 	val = ffs(addr_width) - 1;
218 	return val | (val << 8);
219 }
220 
221 void fsl_edma_free_desc(struct virt_dma_desc *vdesc)
222 {
223 	struct fsl_edma_desc *fsl_desc;
224 	int i;
225 
226 	fsl_desc = to_fsl_edma_desc(vdesc);
227 	for (i = 0; i < fsl_desc->n_tcds; i++)
228 		dma_pool_free(fsl_desc->echan->tcd_pool, fsl_desc->tcd[i].vtcd,
229 			      fsl_desc->tcd[i].ptcd);
230 	kfree(fsl_desc);
231 }
232 
233 int fsl_edma_terminate_all(struct dma_chan *chan)
234 {
235 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
236 	unsigned long flags;
237 	LIST_HEAD(head);
238 
239 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
240 	fsl_edma_disable_request(fsl_chan);
241 	fsl_chan->edesc = NULL;
242 	fsl_chan->idle = true;
243 	vchan_get_all_descriptors(&fsl_chan->vchan, &head);
244 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
245 	vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
246 
247 	if (fsl_edma_drvflags(fsl_chan) & FSL_EDMA_DRV_HAS_PD)
248 		pm_runtime_allow(fsl_chan->pd_dev);
249 
250 	return 0;
251 }
252 
253 int fsl_edma_pause(struct dma_chan *chan)
254 {
255 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
256 	unsigned long flags;
257 
258 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
259 	if (fsl_chan->edesc) {
260 		fsl_edma_disable_request(fsl_chan);
261 		fsl_chan->status = DMA_PAUSED;
262 		fsl_chan->idle = true;
263 	}
264 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
265 	return 0;
266 }
267 
268 int fsl_edma_resume(struct dma_chan *chan)
269 {
270 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
271 	unsigned long flags;
272 
273 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
274 	if (fsl_chan->edesc) {
275 		fsl_edma_enable_request(fsl_chan);
276 		fsl_chan->status = DMA_IN_PROGRESS;
277 		fsl_chan->idle = false;
278 	}
279 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
280 	return 0;
281 }
282 
283 static void fsl_edma_unprep_slave_dma(struct fsl_edma_chan *fsl_chan)
284 {
285 	if (fsl_chan->dma_dir != DMA_NONE)
286 		dma_unmap_resource(fsl_chan->vchan.chan.device->dev,
287 				   fsl_chan->dma_dev_addr,
288 				   fsl_chan->dma_dev_size,
289 				   fsl_chan->dma_dir, 0);
290 	fsl_chan->dma_dir = DMA_NONE;
291 }
292 
293 static bool fsl_edma_prep_slave_dma(struct fsl_edma_chan *fsl_chan,
294 				    enum dma_transfer_direction dir)
295 {
296 	struct device *dev = fsl_chan->vchan.chan.device->dev;
297 	enum dma_data_direction dma_dir;
298 	phys_addr_t addr = 0;
299 	u32 size = 0;
300 
301 	switch (dir) {
302 	case DMA_MEM_TO_DEV:
303 		dma_dir = DMA_FROM_DEVICE;
304 		addr = fsl_chan->cfg.dst_addr;
305 		size = fsl_chan->cfg.dst_maxburst;
306 		break;
307 	case DMA_DEV_TO_MEM:
308 		dma_dir = DMA_TO_DEVICE;
309 		addr = fsl_chan->cfg.src_addr;
310 		size = fsl_chan->cfg.src_maxburst;
311 		break;
312 	default:
313 		dma_dir = DMA_NONE;
314 		break;
315 	}
316 
317 	/* Already mapped for this config? */
318 	if (fsl_chan->dma_dir == dma_dir)
319 		return true;
320 
321 	fsl_edma_unprep_slave_dma(fsl_chan);
322 
323 	fsl_chan->dma_dev_addr = dma_map_resource(dev, addr, size, dma_dir, 0);
324 	if (dma_mapping_error(dev, fsl_chan->dma_dev_addr))
325 		return false;
326 	fsl_chan->dma_dev_size = size;
327 	fsl_chan->dma_dir = dma_dir;
328 
329 	return true;
330 }
331 
332 int fsl_edma_slave_config(struct dma_chan *chan,
333 				 struct dma_slave_config *cfg)
334 {
335 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
336 
337 	memcpy(&fsl_chan->cfg, cfg, sizeof(*cfg));
338 	fsl_edma_unprep_slave_dma(fsl_chan);
339 
340 	return 0;
341 }
342 
343 static size_t fsl_edma_desc_residue(struct fsl_edma_chan *fsl_chan,
344 		struct virt_dma_desc *vdesc, bool in_progress)
345 {
346 	struct fsl_edma_desc *edesc = fsl_chan->edesc;
347 	enum dma_transfer_direction dir = edesc->dirn;
348 	dma_addr_t cur_addr, dma_addr;
349 	size_t len, size;
350 	u32 nbytes = 0;
351 	int i;
352 
353 	/* calculate the total size in this desc */
354 	for (len = i = 0; i < fsl_chan->edesc->n_tcds; i++) {
355 		nbytes = le32_to_cpu(edesc->tcd[i].vtcd->nbytes);
356 		if (nbytes & (EDMA_V3_TCD_NBYTES_DMLOE | EDMA_V3_TCD_NBYTES_SMLOE))
357 			nbytes = EDMA_V3_TCD_NBYTES_MLOFF_NBYTES(nbytes);
358 		len += nbytes * le16_to_cpu(edesc->tcd[i].vtcd->biter);
359 	}
360 
361 	if (!in_progress)
362 		return len;
363 
364 	if (dir == DMA_MEM_TO_DEV)
365 		cur_addr = edma_read_tcdreg(fsl_chan, saddr);
366 	else
367 		cur_addr = edma_read_tcdreg(fsl_chan, daddr);
368 
369 	/* figure out the finished and calculate the residue */
370 	for (i = 0; i < fsl_chan->edesc->n_tcds; i++) {
371 		nbytes = le32_to_cpu(edesc->tcd[i].vtcd->nbytes);
372 		if (nbytes & (EDMA_V3_TCD_NBYTES_DMLOE | EDMA_V3_TCD_NBYTES_SMLOE))
373 			nbytes = EDMA_V3_TCD_NBYTES_MLOFF_NBYTES(nbytes);
374 
375 		size = nbytes * le16_to_cpu(edesc->tcd[i].vtcd->biter);
376 
377 		if (dir == DMA_MEM_TO_DEV)
378 			dma_addr = le32_to_cpu(edesc->tcd[i].vtcd->saddr);
379 		else
380 			dma_addr = le32_to_cpu(edesc->tcd[i].vtcd->daddr);
381 
382 		len -= size;
383 		if (cur_addr >= dma_addr && cur_addr < dma_addr + size) {
384 			len += dma_addr + size - cur_addr;
385 			break;
386 		}
387 	}
388 
389 	return len;
390 }
391 
392 enum dma_status fsl_edma_tx_status(struct dma_chan *chan,
393 		dma_cookie_t cookie, struct dma_tx_state *txstate)
394 {
395 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
396 	struct virt_dma_desc *vdesc;
397 	enum dma_status status;
398 	unsigned long flags;
399 
400 	status = dma_cookie_status(chan, cookie, txstate);
401 	if (status == DMA_COMPLETE)
402 		return status;
403 
404 	if (!txstate)
405 		return fsl_chan->status;
406 
407 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
408 	vdesc = vchan_find_desc(&fsl_chan->vchan, cookie);
409 	if (fsl_chan->edesc && cookie == fsl_chan->edesc->vdesc.tx.cookie)
410 		txstate->residue =
411 			fsl_edma_desc_residue(fsl_chan, vdesc, true);
412 	else if (vdesc)
413 		txstate->residue =
414 			fsl_edma_desc_residue(fsl_chan, vdesc, false);
415 	else
416 		txstate->residue = 0;
417 
418 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
419 
420 	return fsl_chan->status;
421 }
422 
423 static void fsl_edma_set_tcd_regs(struct fsl_edma_chan *fsl_chan,
424 				  struct fsl_edma_hw_tcd *tcd)
425 {
426 	u16 csr = 0;
427 
428 	/*
429 	 * TCD parameters are stored in struct fsl_edma_hw_tcd in little
430 	 * endian format. However, we need to load the TCD registers in
431 	 * big- or little-endian obeying the eDMA engine model endian,
432 	 * and this is performed from specific edma_write functions
433 	 */
434 	edma_write_tcdreg(fsl_chan, 0, csr);
435 
436 	edma_write_tcdreg(fsl_chan, tcd->saddr, saddr);
437 	edma_write_tcdreg(fsl_chan, tcd->daddr, daddr);
438 
439 	edma_write_tcdreg(fsl_chan, tcd->attr, attr);
440 	edma_write_tcdreg(fsl_chan, tcd->soff, soff);
441 
442 	edma_write_tcdreg(fsl_chan, tcd->nbytes, nbytes);
443 	edma_write_tcdreg(fsl_chan, tcd->slast, slast);
444 
445 	edma_write_tcdreg(fsl_chan, tcd->citer, citer);
446 	edma_write_tcdreg(fsl_chan, tcd->biter, biter);
447 	edma_write_tcdreg(fsl_chan, tcd->doff, doff);
448 
449 	edma_write_tcdreg(fsl_chan, tcd->dlast_sga, dlast_sga);
450 
451 	if (fsl_chan->is_sw) {
452 		csr = le16_to_cpu(tcd->csr);
453 		csr |= EDMA_TCD_CSR_START;
454 		tcd->csr = cpu_to_le16(csr);
455 	}
456 
457 	edma_write_tcdreg(fsl_chan, tcd->csr, csr);
458 }
459 
460 static inline
461 void fsl_edma_fill_tcd(struct fsl_edma_chan *fsl_chan,
462 		       struct fsl_edma_hw_tcd *tcd, u32 src, u32 dst,
463 		       u16 attr, u16 soff, u32 nbytes, u32 slast, u16 citer,
464 		       u16 biter, u16 doff, u32 dlast_sga, bool major_int,
465 		       bool disable_req, bool enable_sg)
466 {
467 	struct dma_slave_config *cfg = &fsl_chan->cfg;
468 	u16 csr = 0;
469 	u32 burst;
470 
471 	/*
472 	 * eDMA hardware SGs require the TCDs to be stored in little
473 	 * endian format irrespective of the register endian model.
474 	 * So we put the value in little endian in memory, waiting
475 	 * for fsl_edma_set_tcd_regs doing the swap.
476 	 */
477 	tcd->saddr = cpu_to_le32(src);
478 	tcd->daddr = cpu_to_le32(dst);
479 
480 	tcd->attr = cpu_to_le16(attr);
481 
482 	tcd->soff = cpu_to_le16(soff);
483 
484 	if (fsl_chan->is_multi_fifo) {
485 		/* set mloff to support multiple fifo */
486 		burst = cfg->direction == DMA_DEV_TO_MEM ?
487 				cfg->src_addr_width : cfg->dst_addr_width;
488 		nbytes |= EDMA_V3_TCD_NBYTES_MLOFF(-(burst * 4));
489 		/* enable DMLOE/SMLOE */
490 		if (cfg->direction == DMA_MEM_TO_DEV) {
491 			nbytes |= EDMA_V3_TCD_NBYTES_DMLOE;
492 			nbytes &= ~EDMA_V3_TCD_NBYTES_SMLOE;
493 		} else {
494 			nbytes |= EDMA_V3_TCD_NBYTES_SMLOE;
495 			nbytes &= ~EDMA_V3_TCD_NBYTES_DMLOE;
496 		}
497 	}
498 
499 	tcd->nbytes = cpu_to_le32(nbytes);
500 	tcd->slast = cpu_to_le32(slast);
501 
502 	tcd->citer = cpu_to_le16(EDMA_TCD_CITER_CITER(citer));
503 	tcd->doff = cpu_to_le16(doff);
504 
505 	tcd->dlast_sga = cpu_to_le32(dlast_sga);
506 
507 	tcd->biter = cpu_to_le16(EDMA_TCD_BITER_BITER(biter));
508 	if (major_int)
509 		csr |= EDMA_TCD_CSR_INT_MAJOR;
510 
511 	if (disable_req)
512 		csr |= EDMA_TCD_CSR_D_REQ;
513 
514 	if (enable_sg)
515 		csr |= EDMA_TCD_CSR_E_SG;
516 
517 	if (fsl_chan->is_rxchan)
518 		csr |= EDMA_TCD_CSR_ACTIVE;
519 
520 	if (fsl_chan->is_sw)
521 		csr |= EDMA_TCD_CSR_START;
522 
523 	tcd->csr = cpu_to_le16(csr);
524 }
525 
526 static struct fsl_edma_desc *fsl_edma_alloc_desc(struct fsl_edma_chan *fsl_chan,
527 		int sg_len)
528 {
529 	struct fsl_edma_desc *fsl_desc;
530 	int i;
531 
532 	fsl_desc = kzalloc(struct_size(fsl_desc, tcd, sg_len), GFP_NOWAIT);
533 	if (!fsl_desc)
534 		return NULL;
535 
536 	fsl_desc->echan = fsl_chan;
537 	fsl_desc->n_tcds = sg_len;
538 	for (i = 0; i < sg_len; i++) {
539 		fsl_desc->tcd[i].vtcd = dma_pool_alloc(fsl_chan->tcd_pool,
540 					GFP_NOWAIT, &fsl_desc->tcd[i].ptcd);
541 		if (!fsl_desc->tcd[i].vtcd)
542 			goto err;
543 	}
544 	return fsl_desc;
545 
546 err:
547 	while (--i >= 0)
548 		dma_pool_free(fsl_chan->tcd_pool, fsl_desc->tcd[i].vtcd,
549 				fsl_desc->tcd[i].ptcd);
550 	kfree(fsl_desc);
551 	return NULL;
552 }
553 
554 struct dma_async_tx_descriptor *fsl_edma_prep_dma_cyclic(
555 		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
556 		size_t period_len, enum dma_transfer_direction direction,
557 		unsigned long flags)
558 {
559 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
560 	struct fsl_edma_desc *fsl_desc;
561 	dma_addr_t dma_buf_next;
562 	bool major_int = true;
563 	int sg_len, i;
564 	u32 src_addr, dst_addr, last_sg, nbytes;
565 	u16 soff, doff, iter;
566 
567 	if (!is_slave_direction(direction))
568 		return NULL;
569 
570 	if (!fsl_edma_prep_slave_dma(fsl_chan, direction))
571 		return NULL;
572 
573 	sg_len = buf_len / period_len;
574 	fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
575 	if (!fsl_desc)
576 		return NULL;
577 	fsl_desc->iscyclic = true;
578 	fsl_desc->dirn = direction;
579 
580 	dma_buf_next = dma_addr;
581 	if (direction == DMA_MEM_TO_DEV) {
582 		fsl_chan->attr =
583 			fsl_edma_get_tcd_attr(fsl_chan->cfg.dst_addr_width);
584 		nbytes = fsl_chan->cfg.dst_addr_width *
585 			fsl_chan->cfg.dst_maxburst;
586 	} else {
587 		fsl_chan->attr =
588 			fsl_edma_get_tcd_attr(fsl_chan->cfg.src_addr_width);
589 		nbytes = fsl_chan->cfg.src_addr_width *
590 			fsl_chan->cfg.src_maxburst;
591 	}
592 
593 	iter = period_len / nbytes;
594 
595 	for (i = 0; i < sg_len; i++) {
596 		if (dma_buf_next >= dma_addr + buf_len)
597 			dma_buf_next = dma_addr;
598 
599 		/* get next sg's physical address */
600 		last_sg = fsl_desc->tcd[(i + 1) % sg_len].ptcd;
601 
602 		if (direction == DMA_MEM_TO_DEV) {
603 			src_addr = dma_buf_next;
604 			dst_addr = fsl_chan->dma_dev_addr;
605 			soff = fsl_chan->cfg.dst_addr_width;
606 			doff = fsl_chan->is_multi_fifo ? 4 : 0;
607 		} else if (direction == DMA_DEV_TO_MEM) {
608 			src_addr = fsl_chan->dma_dev_addr;
609 			dst_addr = dma_buf_next;
610 			soff = fsl_chan->is_multi_fifo ? 4 : 0;
611 			doff = fsl_chan->cfg.src_addr_width;
612 		} else {
613 			/* DMA_DEV_TO_DEV */
614 			src_addr = fsl_chan->cfg.src_addr;
615 			dst_addr = fsl_chan->cfg.dst_addr;
616 			soff = doff = 0;
617 			major_int = false;
618 		}
619 
620 		fsl_edma_fill_tcd(fsl_chan, fsl_desc->tcd[i].vtcd, src_addr, dst_addr,
621 				  fsl_chan->attr, soff, nbytes, 0, iter,
622 				  iter, doff, last_sg, major_int, false, true);
623 		dma_buf_next += period_len;
624 	}
625 
626 	return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
627 }
628 
629 struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg(
630 		struct dma_chan *chan, struct scatterlist *sgl,
631 		unsigned int sg_len, enum dma_transfer_direction direction,
632 		unsigned long flags, void *context)
633 {
634 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
635 	struct fsl_edma_desc *fsl_desc;
636 	struct scatterlist *sg;
637 	u32 src_addr, dst_addr, last_sg, nbytes;
638 	u16 soff, doff, iter;
639 	int i;
640 
641 	if (!is_slave_direction(direction))
642 		return NULL;
643 
644 	if (!fsl_edma_prep_slave_dma(fsl_chan, direction))
645 		return NULL;
646 
647 	fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
648 	if (!fsl_desc)
649 		return NULL;
650 	fsl_desc->iscyclic = false;
651 	fsl_desc->dirn = direction;
652 
653 	if (direction == DMA_MEM_TO_DEV) {
654 		fsl_chan->attr =
655 			fsl_edma_get_tcd_attr(fsl_chan->cfg.dst_addr_width);
656 		nbytes = fsl_chan->cfg.dst_addr_width *
657 			fsl_chan->cfg.dst_maxburst;
658 	} else {
659 		fsl_chan->attr =
660 			fsl_edma_get_tcd_attr(fsl_chan->cfg.src_addr_width);
661 		nbytes = fsl_chan->cfg.src_addr_width *
662 			fsl_chan->cfg.src_maxburst;
663 	}
664 
665 	for_each_sg(sgl, sg, sg_len, i) {
666 		if (direction == DMA_MEM_TO_DEV) {
667 			src_addr = sg_dma_address(sg);
668 			dst_addr = fsl_chan->dma_dev_addr;
669 			soff = fsl_chan->cfg.dst_addr_width;
670 			doff = 0;
671 		} else if (direction == DMA_DEV_TO_MEM) {
672 			src_addr = fsl_chan->dma_dev_addr;
673 			dst_addr = sg_dma_address(sg);
674 			soff = 0;
675 			doff = fsl_chan->cfg.src_addr_width;
676 		} else {
677 			/* DMA_DEV_TO_DEV */
678 			src_addr = fsl_chan->cfg.src_addr;
679 			dst_addr = fsl_chan->cfg.dst_addr;
680 			soff = 0;
681 			doff = 0;
682 		}
683 
684 		/*
685 		 * Choose the suitable burst length if sg_dma_len is not
686 		 * multiple of burst length so that the whole transfer length is
687 		 * multiple of minor loop(burst length).
688 		 */
689 		if (sg_dma_len(sg) % nbytes) {
690 			u32 width = (direction == DMA_DEV_TO_MEM) ? doff : soff;
691 			u32 burst = (direction == DMA_DEV_TO_MEM) ?
692 						fsl_chan->cfg.src_maxburst :
693 						fsl_chan->cfg.dst_maxburst;
694 			int j;
695 
696 			for (j = burst; j > 1; j--) {
697 				if (!(sg_dma_len(sg) % (j * width))) {
698 					nbytes = j * width;
699 					break;
700 				}
701 			}
702 			/* Set burst size as 1 if there's no suitable one */
703 			if (j == 1)
704 				nbytes = width;
705 		}
706 		iter = sg_dma_len(sg) / nbytes;
707 		if (i < sg_len - 1) {
708 			last_sg = fsl_desc->tcd[(i + 1)].ptcd;
709 			fsl_edma_fill_tcd(fsl_chan, fsl_desc->tcd[i].vtcd, src_addr,
710 					  dst_addr, fsl_chan->attr, soff,
711 					  nbytes, 0, iter, iter, doff, last_sg,
712 					  false, false, true);
713 		} else {
714 			last_sg = 0;
715 			fsl_edma_fill_tcd(fsl_chan, fsl_desc->tcd[i].vtcd, src_addr,
716 					  dst_addr, fsl_chan->attr, soff,
717 					  nbytes, 0, iter, iter, doff, last_sg,
718 					  true, true, false);
719 		}
720 	}
721 
722 	return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
723 }
724 
725 struct dma_async_tx_descriptor *fsl_edma_prep_memcpy(struct dma_chan *chan,
726 						     dma_addr_t dma_dst, dma_addr_t dma_src,
727 						     size_t len, unsigned long flags)
728 {
729 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
730 	struct fsl_edma_desc *fsl_desc;
731 
732 	fsl_desc = fsl_edma_alloc_desc(fsl_chan, 1);
733 	if (!fsl_desc)
734 		return NULL;
735 	fsl_desc->iscyclic = false;
736 
737 	fsl_chan->is_sw = true;
738 
739 	/* To match with copy_align and max_seg_size so 1 tcd is enough */
740 	fsl_edma_fill_tcd(fsl_chan, fsl_desc->tcd[0].vtcd, dma_src, dma_dst,
741 			fsl_edma_get_tcd_attr(DMA_SLAVE_BUSWIDTH_32_BYTES),
742 			32, len, 0, 1, 1, 32, 0, true, true, false);
743 
744 	return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
745 }
746 
747 void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan)
748 {
749 	struct virt_dma_desc *vdesc;
750 
751 	lockdep_assert_held(&fsl_chan->vchan.lock);
752 
753 	vdesc = vchan_next_desc(&fsl_chan->vchan);
754 	if (!vdesc)
755 		return;
756 	fsl_chan->edesc = to_fsl_edma_desc(vdesc);
757 	fsl_edma_set_tcd_regs(fsl_chan, fsl_chan->edesc->tcd[0].vtcd);
758 	fsl_edma_enable_request(fsl_chan);
759 	fsl_chan->status = DMA_IN_PROGRESS;
760 	fsl_chan->idle = false;
761 }
762 
763 void fsl_edma_issue_pending(struct dma_chan *chan)
764 {
765 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
766 	unsigned long flags;
767 
768 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
769 
770 	if (unlikely(fsl_chan->pm_state != RUNNING)) {
771 		spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
772 		/* cannot submit due to suspend */
773 		return;
774 	}
775 
776 	if (vchan_issue_pending(&fsl_chan->vchan) && !fsl_chan->edesc)
777 		fsl_edma_xfer_desc(fsl_chan);
778 
779 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
780 }
781 
782 int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
783 {
784 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
785 
786 	fsl_chan->tcd_pool = dma_pool_create("tcd_pool", chan->device->dev,
787 				sizeof(struct fsl_edma_hw_tcd),
788 				32, 0);
789 	return 0;
790 }
791 
792 void fsl_edma_free_chan_resources(struct dma_chan *chan)
793 {
794 	struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
795 	struct fsl_edma_engine *edma = fsl_chan->edma;
796 	unsigned long flags;
797 	LIST_HEAD(head);
798 
799 	spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
800 	fsl_edma_disable_request(fsl_chan);
801 	if (edma->drvdata->dmamuxs)
802 		fsl_edma_chan_mux(fsl_chan, 0, false);
803 	fsl_chan->edesc = NULL;
804 	vchan_get_all_descriptors(&fsl_chan->vchan, &head);
805 	fsl_edma_unprep_slave_dma(fsl_chan);
806 	spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
807 
808 	vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
809 	dma_pool_destroy(fsl_chan->tcd_pool);
810 	fsl_chan->tcd_pool = NULL;
811 	fsl_chan->is_sw = false;
812 }
813 
814 void fsl_edma_cleanup_vchan(struct dma_device *dmadev)
815 {
816 	struct fsl_edma_chan *chan, *_chan;
817 
818 	list_for_each_entry_safe(chan, _chan,
819 				&dmadev->channels, vchan.chan.device_node) {
820 		list_del(&chan->vchan.chan.device_node);
821 		tasklet_kill(&chan->vchan.task);
822 	}
823 }
824 
825 /*
826  * On the 32 channels Vybrid/mpc577x edma version, register offsets are
827  * different compared to ColdFire mcf5441x 64 channels edma.
828  *
829  * This function sets up register offsets as per proper declared version
830  * so must be called in xxx_edma_probe() just after setting the
831  * edma "version" and "membase" appropriately.
832  */
833 void fsl_edma_setup_regs(struct fsl_edma_engine *edma)
834 {
835 	bool is64 = !!(edma->drvdata->flags & FSL_EDMA_DRV_EDMA64);
836 
837 	edma->regs.cr = edma->membase + EDMA_CR;
838 	edma->regs.es = edma->membase + EDMA_ES;
839 	edma->regs.erql = edma->membase + EDMA_ERQ;
840 	edma->regs.eeil = edma->membase + EDMA_EEI;
841 
842 	edma->regs.serq = edma->membase + (is64 ? EDMA64_SERQ : EDMA_SERQ);
843 	edma->regs.cerq = edma->membase + (is64 ? EDMA64_CERQ : EDMA_CERQ);
844 	edma->regs.seei = edma->membase + (is64 ? EDMA64_SEEI : EDMA_SEEI);
845 	edma->regs.ceei = edma->membase + (is64 ? EDMA64_CEEI : EDMA_CEEI);
846 	edma->regs.cint = edma->membase + (is64 ? EDMA64_CINT : EDMA_CINT);
847 	edma->regs.cerr = edma->membase + (is64 ? EDMA64_CERR : EDMA_CERR);
848 	edma->regs.ssrt = edma->membase + (is64 ? EDMA64_SSRT : EDMA_SSRT);
849 	edma->regs.cdne = edma->membase + (is64 ? EDMA64_CDNE : EDMA_CDNE);
850 	edma->regs.intl = edma->membase + (is64 ? EDMA64_INTL : EDMA_INTR);
851 	edma->regs.errl = edma->membase + (is64 ? EDMA64_ERRL : EDMA_ERR);
852 
853 	if (is64) {
854 		edma->regs.erqh = edma->membase + EDMA64_ERQH;
855 		edma->regs.eeih = edma->membase + EDMA64_EEIH;
856 		edma->regs.errh = edma->membase + EDMA64_ERRH;
857 		edma->regs.inth = edma->membase + EDMA64_INTH;
858 	}
859 }
860 
861 MODULE_LICENSE("GPL v2");
862