xref: /linux/drivers/rapidio/devices/tsi721_dma.c (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DMA Engine support for Tsi721 PCIExpress-to-SRIO bridge
4  *
5  * Copyright (c) 2011-2014 Integrated Device Technology, Inc.
6  * Alexandre Bounine <alexandre.bounine@idt.com>
7  */
8 
9 #include <linux/io.h>
10 #include <linux/errno.h>
11 #include <linux/init.h>
12 #include <linux/ioport.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/pci.h>
16 #include <linux/rio.h>
17 #include <linux/rio_drv.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/interrupt.h>
20 #include <linux/kfifo.h>
21 #include <linux/sched.h>
22 #include <linux/delay.h>
23 #include "../../dma/dmaengine.h"
24 
25 #include "tsi721.h"
26 
27 #ifdef CONFIG_PCI_MSI
28 static irqreturn_t tsi721_bdma_msix(int irq, void *ptr);
29 #endif
30 static int tsi721_submit_sg(struct tsi721_tx_desc *desc);
31 
32 static unsigned int dma_desc_per_channel = 128;
33 module_param(dma_desc_per_channel, uint, S_IRUGO);
34 MODULE_PARM_DESC(dma_desc_per_channel,
35 		 "Number of DMA descriptors per channel (default: 128)");
36 
37 static unsigned int dma_txqueue_sz = 16;
38 module_param(dma_txqueue_sz, uint, S_IRUGO);
39 MODULE_PARM_DESC(dma_txqueue_sz,
40 		 "DMA Transactions Queue Size (default: 16)");
41 
42 static u8 dma_sel = 0x7f;
43 module_param(dma_sel, byte, S_IRUGO);
44 MODULE_PARM_DESC(dma_sel,
45 		 "DMA Channel Selection Mask (default: 0x7f = all)");
46 
47 static inline struct tsi721_bdma_chan *to_tsi721_chan(struct dma_chan *chan)
48 {
49 	return container_of(chan, struct tsi721_bdma_chan, dchan);
50 }
51 
52 static inline struct tsi721_device *to_tsi721(struct dma_device *ddev)
53 {
54 	return container_of(ddev, struct rio_mport, dma)->priv;
55 }
56 
57 static inline
58 struct tsi721_tx_desc *to_tsi721_desc(struct dma_async_tx_descriptor *txd)
59 {
60 	return container_of(txd, struct tsi721_tx_desc, txd);
61 }
62 
63 static int tsi721_bdma_ch_init(struct tsi721_bdma_chan *bdma_chan, int bd_num)
64 {
65 	struct tsi721_dma_desc *bd_ptr;
66 	struct device *dev = bdma_chan->dchan.device->dev;
67 	u64		*sts_ptr;
68 	dma_addr_t	bd_phys;
69 	dma_addr_t	sts_phys;
70 	int		sts_size;
71 #ifdef CONFIG_PCI_MSI
72 	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
73 #endif
74 
75 	tsi_debug(DMA, &bdma_chan->dchan.dev->device, "DMAC%d", bdma_chan->id);
76 
77 	/*
78 	 * Allocate space for DMA descriptors
79 	 * (add an extra element for link descriptor)
80 	 */
81 	bd_ptr = dma_alloc_coherent(dev,
82 				    (bd_num + 1) * sizeof(struct tsi721_dma_desc),
83 				    &bd_phys, GFP_ATOMIC);
84 	if (!bd_ptr)
85 		return -ENOMEM;
86 
87 	bdma_chan->bd_num = bd_num;
88 	bdma_chan->bd_phys = bd_phys;
89 	bdma_chan->bd_base = bd_ptr;
90 
91 	tsi_debug(DMA, &bdma_chan->dchan.dev->device,
92 		  "DMAC%d descriptors @ %p (phys = %pad)",
93 		  bdma_chan->id, bd_ptr, &bd_phys);
94 
95 	/* Allocate space for descriptor status FIFO */
96 	sts_size = ((bd_num + 1) >= TSI721_DMA_MINSTSSZ) ?
97 					(bd_num + 1) : TSI721_DMA_MINSTSSZ;
98 	sts_size = roundup_pow_of_two(sts_size);
99 	sts_ptr = dma_alloc_coherent(dev,
100 				     sts_size * sizeof(struct tsi721_dma_sts),
101 				     &sts_phys, GFP_ATOMIC);
102 	if (!sts_ptr) {
103 		/* Free space allocated for DMA descriptors */
104 		dma_free_coherent(dev,
105 				  (bd_num + 1) * sizeof(struct tsi721_dma_desc),
106 				  bd_ptr, bd_phys);
107 		bdma_chan->bd_base = NULL;
108 		return -ENOMEM;
109 	}
110 
111 	bdma_chan->sts_phys = sts_phys;
112 	bdma_chan->sts_base = sts_ptr;
113 	bdma_chan->sts_size = sts_size;
114 
115 	tsi_debug(DMA, &bdma_chan->dchan.dev->device,
116 		"DMAC%d desc status FIFO @ %p (phys = %pad) size=0x%x",
117 		bdma_chan->id, sts_ptr, &sts_phys, sts_size);
118 
119 	/* Initialize DMA descriptors ring using added link descriptor */
120 	bd_ptr[bd_num].type_id = cpu_to_le32(DTYPE3 << 29);
121 	bd_ptr[bd_num].next_lo = cpu_to_le32((u64)bd_phys &
122 						 TSI721_DMAC_DPTRL_MASK);
123 	bd_ptr[bd_num].next_hi = cpu_to_le32((u64)bd_phys >> 32);
124 
125 	/* Setup DMA descriptor pointers */
126 	iowrite32(((u64)bd_phys >> 32),
127 		bdma_chan->regs + TSI721_DMAC_DPTRH);
128 	iowrite32(((u64)bd_phys & TSI721_DMAC_DPTRL_MASK),
129 		bdma_chan->regs + TSI721_DMAC_DPTRL);
130 
131 	/* Setup descriptor status FIFO */
132 	iowrite32(((u64)sts_phys >> 32),
133 		bdma_chan->regs + TSI721_DMAC_DSBH);
134 	iowrite32(((u64)sts_phys & TSI721_DMAC_DSBL_MASK),
135 		bdma_chan->regs + TSI721_DMAC_DSBL);
136 	iowrite32(TSI721_DMAC_DSSZ_SIZE(sts_size),
137 		bdma_chan->regs + TSI721_DMAC_DSSZ);
138 
139 	/* Clear interrupt bits */
140 	iowrite32(TSI721_DMAC_INT_ALL,
141 		bdma_chan->regs + TSI721_DMAC_INT);
142 
143 	ioread32(bdma_chan->regs + TSI721_DMAC_INT);
144 
145 #ifdef CONFIG_PCI_MSI
146 	/* Request interrupt service if we are in MSI-X mode */
147 	if (priv->flags & TSI721_USING_MSIX) {
148 		int rc, idx;
149 
150 		idx = TSI721_VECT_DMA0_DONE + bdma_chan->id;
151 
152 		rc = request_irq(priv->msix[idx].vector, tsi721_bdma_msix, 0,
153 				 priv->msix[idx].irq_name, (void *)bdma_chan);
154 
155 		if (rc) {
156 			tsi_debug(DMA, &bdma_chan->dchan.dev->device,
157 				  "Unable to get MSI-X for DMAC%d-DONE",
158 				  bdma_chan->id);
159 			goto err_out;
160 		}
161 
162 		idx = TSI721_VECT_DMA0_INT + bdma_chan->id;
163 
164 		rc = request_irq(priv->msix[idx].vector, tsi721_bdma_msix, 0,
165 				priv->msix[idx].irq_name, (void *)bdma_chan);
166 
167 		if (rc)	{
168 			tsi_debug(DMA, &bdma_chan->dchan.dev->device,
169 				  "Unable to get MSI-X for DMAC%d-INT",
170 				  bdma_chan->id);
171 			free_irq(
172 				priv->msix[TSI721_VECT_DMA0_DONE +
173 					    bdma_chan->id].vector,
174 				(void *)bdma_chan);
175 		}
176 
177 err_out:
178 		if (rc) {
179 			/* Free space allocated for DMA descriptors */
180 			dma_free_coherent(dev,
181 				(bd_num + 1) * sizeof(struct tsi721_dma_desc),
182 				bd_ptr, bd_phys);
183 			bdma_chan->bd_base = NULL;
184 
185 			/* Free space allocated for status descriptors */
186 			dma_free_coherent(dev,
187 				sts_size * sizeof(struct tsi721_dma_sts),
188 				sts_ptr, sts_phys);
189 			bdma_chan->sts_base = NULL;
190 
191 			return -EIO;
192 		}
193 	}
194 #endif /* CONFIG_PCI_MSI */
195 
196 	/* Toggle DMA channel initialization */
197 	iowrite32(TSI721_DMAC_CTL_INIT,	bdma_chan->regs + TSI721_DMAC_CTL);
198 	ioread32(bdma_chan->regs + TSI721_DMAC_CTL);
199 	bdma_chan->wr_count = bdma_chan->wr_count_next = 0;
200 	bdma_chan->sts_rdptr = 0;
201 	udelay(10);
202 
203 	return 0;
204 }
205 
206 static int tsi721_bdma_ch_free(struct tsi721_bdma_chan *bdma_chan)
207 {
208 	u32 ch_stat;
209 #ifdef CONFIG_PCI_MSI
210 	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
211 #endif
212 
213 	if (!bdma_chan->bd_base)
214 		return 0;
215 
216 	/* Check if DMA channel still running */
217 	ch_stat = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
218 	if (ch_stat & TSI721_DMAC_STS_RUN)
219 		return -EFAULT;
220 
221 	/* Put DMA channel into init state */
222 	iowrite32(TSI721_DMAC_CTL_INIT,	bdma_chan->regs + TSI721_DMAC_CTL);
223 
224 #ifdef CONFIG_PCI_MSI
225 	if (priv->flags & TSI721_USING_MSIX) {
226 		free_irq(priv->msix[TSI721_VECT_DMA0_DONE +
227 				    bdma_chan->id].vector, (void *)bdma_chan);
228 		free_irq(priv->msix[TSI721_VECT_DMA0_INT +
229 				    bdma_chan->id].vector, (void *)bdma_chan);
230 	}
231 #endif /* CONFIG_PCI_MSI */
232 
233 	/* Free space allocated for DMA descriptors */
234 	dma_free_coherent(bdma_chan->dchan.device->dev,
235 		(bdma_chan->bd_num + 1) * sizeof(struct tsi721_dma_desc),
236 		bdma_chan->bd_base, bdma_chan->bd_phys);
237 	bdma_chan->bd_base = NULL;
238 
239 	/* Free space allocated for status FIFO */
240 	dma_free_coherent(bdma_chan->dchan.device->dev,
241 		bdma_chan->sts_size * sizeof(struct tsi721_dma_sts),
242 		bdma_chan->sts_base, bdma_chan->sts_phys);
243 	bdma_chan->sts_base = NULL;
244 	return 0;
245 }
246 
247 static void
248 tsi721_bdma_interrupt_enable(struct tsi721_bdma_chan *bdma_chan, int enable)
249 {
250 	if (enable) {
251 		/* Clear pending BDMA channel interrupts */
252 		iowrite32(TSI721_DMAC_INT_ALL,
253 			bdma_chan->regs + TSI721_DMAC_INT);
254 		ioread32(bdma_chan->regs + TSI721_DMAC_INT);
255 		/* Enable BDMA channel interrupts */
256 		iowrite32(TSI721_DMAC_INT_ALL,
257 			bdma_chan->regs + TSI721_DMAC_INTE);
258 	} else {
259 		/* Disable BDMA channel interrupts */
260 		iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
261 		/* Clear pending BDMA channel interrupts */
262 		iowrite32(TSI721_DMAC_INT_ALL,
263 			bdma_chan->regs + TSI721_DMAC_INT);
264 	}
265 
266 }
267 
268 static bool tsi721_dma_is_idle(struct tsi721_bdma_chan *bdma_chan)
269 {
270 	u32 sts;
271 
272 	sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
273 	return ((sts & TSI721_DMAC_STS_RUN) == 0);
274 }
275 
276 void tsi721_bdma_handler(struct tsi721_bdma_chan *bdma_chan)
277 {
278 	/* Disable BDMA channel interrupts */
279 	iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
280 	if (bdma_chan->active)
281 		tasklet_hi_schedule(&bdma_chan->tasklet);
282 }
283 
284 #ifdef CONFIG_PCI_MSI
285 /**
286  * tsi721_bdma_msix - MSI-X interrupt handler for BDMA channels
287  * @irq: Linux interrupt number
288  * @ptr: Pointer to interrupt-specific data (BDMA channel structure)
289  *
290  * Handles BDMA channel interrupts signaled using MSI-X.
291  *
292  * Returns: %IRQ_HANDLED
293  */
294 static irqreturn_t tsi721_bdma_msix(int irq, void *ptr)
295 {
296 	struct tsi721_bdma_chan *bdma_chan = ptr;
297 
298 	if (bdma_chan->active)
299 		tasklet_hi_schedule(&bdma_chan->tasklet);
300 	return IRQ_HANDLED;
301 }
302 #endif /* CONFIG_PCI_MSI */
303 
304 /* Must be called with the spinlock held */
305 static void tsi721_start_dma(struct tsi721_bdma_chan *bdma_chan)
306 {
307 	if (!tsi721_dma_is_idle(bdma_chan)) {
308 		tsi_err(&bdma_chan->dchan.dev->device,
309 			"DMAC%d Attempt to start non-idle channel",
310 			bdma_chan->id);
311 		return;
312 	}
313 
314 	if (bdma_chan->wr_count == bdma_chan->wr_count_next) {
315 		tsi_err(&bdma_chan->dchan.dev->device,
316 			"DMAC%d Attempt to start DMA with no BDs ready %d",
317 			bdma_chan->id, task_pid_nr(current));
318 		return;
319 	}
320 
321 	tsi_debug(DMA, &bdma_chan->dchan.dev->device, "DMAC%d (wrc=%d) %d",
322 		  bdma_chan->id, bdma_chan->wr_count_next,
323 		  task_pid_nr(current));
324 
325 	iowrite32(bdma_chan->wr_count_next,
326 		bdma_chan->regs + TSI721_DMAC_DWRCNT);
327 	ioread32(bdma_chan->regs + TSI721_DMAC_DWRCNT);
328 
329 	bdma_chan->wr_count = bdma_chan->wr_count_next;
330 }
331 
332 static int
333 tsi721_desc_fill_init(struct tsi721_tx_desc *desc,
334 		      struct tsi721_dma_desc *bd_ptr,
335 		      struct scatterlist *sg, u32 sys_size)
336 {
337 	u64 rio_addr;
338 
339 	if (!bd_ptr)
340 		return -EINVAL;
341 
342 	/* Initialize DMA descriptor */
343 	bd_ptr->type_id = cpu_to_le32((DTYPE1 << 29) |
344 				      (desc->rtype << 19) | desc->destid);
345 	bd_ptr->bcount = cpu_to_le32(((desc->rio_addr & 0x3) << 30) |
346 				     (sys_size << 26));
347 	rio_addr = (desc->rio_addr >> 2) |
348 				((u64)(desc->rio_addr_u & 0x3) << 62);
349 	bd_ptr->raddr_lo = cpu_to_le32(rio_addr & 0xffffffff);
350 	bd_ptr->raddr_hi = cpu_to_le32(rio_addr >> 32);
351 	bd_ptr->t1.bufptr_lo = cpu_to_le32(
352 					(u64)sg_dma_address(sg) & 0xffffffff);
353 	bd_ptr->t1.bufptr_hi = cpu_to_le32((u64)sg_dma_address(sg) >> 32);
354 	bd_ptr->t1.s_dist = 0;
355 	bd_ptr->t1.s_size = 0;
356 
357 	return 0;
358 }
359 
360 static int
361 tsi721_desc_fill_end(struct tsi721_dma_desc *bd_ptr, u32 bcount, bool interrupt)
362 {
363 	if (!bd_ptr)
364 		return -EINVAL;
365 
366 	/* Update DMA descriptor */
367 	if (interrupt)
368 		bd_ptr->type_id |= cpu_to_le32(TSI721_DMAD_IOF);
369 	bd_ptr->bcount |= cpu_to_le32(bcount & TSI721_DMAD_BCOUNT1);
370 
371 	return 0;
372 }
373 
374 static void tsi721_dma_tx_err(struct tsi721_bdma_chan *bdma_chan,
375 			      struct tsi721_tx_desc *desc)
376 {
377 	struct dma_async_tx_descriptor *txd = &desc->txd;
378 	dma_async_tx_callback callback = txd->callback;
379 	void *param = txd->callback_param;
380 
381 	list_move(&desc->desc_node, &bdma_chan->free_list);
382 
383 	if (callback)
384 		callback(param);
385 }
386 
387 static void tsi721_clr_stat(struct tsi721_bdma_chan *bdma_chan)
388 {
389 	u32 srd_ptr;
390 	u64 *sts_ptr;
391 	int i, j;
392 
393 	/* Check and clear descriptor status FIFO entries */
394 	srd_ptr = bdma_chan->sts_rdptr;
395 	sts_ptr = bdma_chan->sts_base;
396 	j = srd_ptr * 8;
397 	while (sts_ptr[j]) {
398 		for (i = 0; i < 8 && sts_ptr[j]; i++, j++)
399 			sts_ptr[j] = 0;
400 
401 		++srd_ptr;
402 		srd_ptr %= bdma_chan->sts_size;
403 		j = srd_ptr * 8;
404 	}
405 
406 	iowrite32(srd_ptr, bdma_chan->regs + TSI721_DMAC_DSRP);
407 	bdma_chan->sts_rdptr = srd_ptr;
408 }
409 
410 /* Must be called with the channel spinlock held */
411 static int tsi721_submit_sg(struct tsi721_tx_desc *desc)
412 {
413 	struct dma_chan *dchan = desc->txd.chan;
414 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
415 	u32 sys_size;
416 	u64 rio_addr;
417 	dma_addr_t next_addr;
418 	u32 bcount;
419 	struct scatterlist *sg;
420 	unsigned int i;
421 	int err = 0;
422 	struct tsi721_dma_desc *bd_ptr = NULL;
423 	u32 idx, rd_idx;
424 	u32 add_count = 0;
425 	struct device *ch_dev = &dchan->dev->device;
426 
427 	if (!tsi721_dma_is_idle(bdma_chan)) {
428 		tsi_err(ch_dev, "DMAC%d ERR: Attempt to use non-idle channel",
429 			bdma_chan->id);
430 		return -EIO;
431 	}
432 
433 	/*
434 	 * Fill DMA channel's hardware buffer descriptors.
435 	 * (NOTE: RapidIO destination address is limited to 64 bits for now)
436 	 */
437 	rio_addr = desc->rio_addr;
438 	next_addr = -1;
439 	bcount = 0;
440 	sys_size = dma_to_mport(dchan->device)->sys_size;
441 
442 	rd_idx = ioread32(bdma_chan->regs + TSI721_DMAC_DRDCNT);
443 	rd_idx %= (bdma_chan->bd_num + 1);
444 
445 	idx = bdma_chan->wr_count_next % (bdma_chan->bd_num + 1);
446 	if (idx == bdma_chan->bd_num) {
447 		/* wrap around link descriptor */
448 		idx = 0;
449 		add_count++;
450 	}
451 
452 	tsi_debug(DMA, ch_dev, "DMAC%d BD ring status: rdi=%d wri=%d",
453 		  bdma_chan->id, rd_idx, idx);
454 
455 	for_each_sg(desc->sg, sg, desc->sg_len, i) {
456 
457 		tsi_debug(DMAV, ch_dev, "DMAC%d sg%d/%d addr: 0x%llx len: %d",
458 			bdma_chan->id, i, desc->sg_len,
459 			(unsigned long long)sg_dma_address(sg), sg_dma_len(sg));
460 
461 		if (sg_dma_len(sg) > TSI721_BDMA_MAX_BCOUNT) {
462 			tsi_err(ch_dev, "DMAC%d SG entry %d is too large",
463 				bdma_chan->id, i);
464 			err = -EINVAL;
465 			break;
466 		}
467 
468 		/*
469 		 * If this sg entry forms contiguous block with previous one,
470 		 * try to merge it into existing DMA descriptor
471 		 */
472 		if (next_addr == sg_dma_address(sg) &&
473 		    bcount + sg_dma_len(sg) <= TSI721_BDMA_MAX_BCOUNT) {
474 			/* Adjust byte count of the descriptor */
475 			bcount += sg_dma_len(sg);
476 			goto entry_done;
477 		} else if (next_addr != -1) {
478 			/* Finalize descriptor using total byte count value */
479 			tsi721_desc_fill_end(bd_ptr, bcount, 0);
480 			tsi_debug(DMAV, ch_dev,	"DMAC%d prev desc final len: %d",
481 				  bdma_chan->id, bcount);
482 		}
483 
484 		desc->rio_addr = rio_addr;
485 
486 		if (i && idx == rd_idx) {
487 			tsi_debug(DMAV, ch_dev,
488 				  "DMAC%d HW descriptor ring is full @ %d",
489 				  bdma_chan->id, i);
490 			desc->sg = sg;
491 			desc->sg_len -= i;
492 			break;
493 		}
494 
495 		bd_ptr = &((struct tsi721_dma_desc *)bdma_chan->bd_base)[idx];
496 		err = tsi721_desc_fill_init(desc, bd_ptr, sg, sys_size);
497 		if (err) {
498 			tsi_err(ch_dev, "Failed to build desc: err=%d", err);
499 			break;
500 		}
501 
502 		tsi_debug(DMAV, ch_dev, "DMAC%d bd_ptr = %p did=%d raddr=0x%llx",
503 			  bdma_chan->id, bd_ptr, desc->destid, desc->rio_addr);
504 
505 		next_addr = sg_dma_address(sg);
506 		bcount = sg_dma_len(sg);
507 
508 		add_count++;
509 		if (++idx == bdma_chan->bd_num) {
510 			/* wrap around link descriptor */
511 			idx = 0;
512 			add_count++;
513 		}
514 
515 entry_done:
516 		if (sg_is_last(sg)) {
517 			tsi721_desc_fill_end(bd_ptr, bcount, 0);
518 			tsi_debug(DMAV, ch_dev,
519 				  "DMAC%d last desc final len: %d",
520 				  bdma_chan->id, bcount);
521 			desc->sg_len = 0;
522 		} else {
523 			rio_addr += sg_dma_len(sg);
524 			next_addr += sg_dma_len(sg);
525 		}
526 	}
527 
528 	if (!err)
529 		bdma_chan->wr_count_next += add_count;
530 
531 	return err;
532 }
533 
534 static void tsi721_advance_work(struct tsi721_bdma_chan *bdma_chan,
535 				struct tsi721_tx_desc *desc)
536 {
537 	int err;
538 
539 	tsi_debug(DMA, &bdma_chan->dchan.dev->device, "DMAC%d", bdma_chan->id);
540 
541 	if (!tsi721_dma_is_idle(bdma_chan))
542 		return;
543 
544 	/*
545 	 * If there is no data transfer in progress, fetch new descriptor from
546 	 * the pending queue.
547 	*/
548 	if (!desc && !bdma_chan->active_tx && !list_empty(&bdma_chan->queue)) {
549 		desc = list_first_entry(&bdma_chan->queue,
550 					struct tsi721_tx_desc, desc_node);
551 		list_del_init((&desc->desc_node));
552 		bdma_chan->active_tx = desc;
553 	}
554 
555 	if (desc) {
556 		err = tsi721_submit_sg(desc);
557 		if (!err)
558 			tsi721_start_dma(bdma_chan);
559 		else {
560 			tsi721_dma_tx_err(bdma_chan, desc);
561 			tsi_debug(DMA, &bdma_chan->dchan.dev->device,
562 				"DMAC%d ERR: tsi721_submit_sg failed with err=%d",
563 				bdma_chan->id, err);
564 		}
565 	}
566 
567 	tsi_debug(DMA, &bdma_chan->dchan.dev->device, "DMAC%d Exit",
568 		  bdma_chan->id);
569 }
570 
571 static void tsi721_dma_tasklet(unsigned long data)
572 {
573 	struct tsi721_bdma_chan *bdma_chan = (struct tsi721_bdma_chan *)data;
574 	u32 dmac_int, dmac_sts;
575 
576 	dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
577 	tsi_debug(DMA, &bdma_chan->dchan.dev->device, "DMAC%d_INT = 0x%x",
578 		  bdma_chan->id, dmac_int);
579 	/* Clear channel interrupts */
580 	iowrite32(dmac_int, bdma_chan->regs + TSI721_DMAC_INT);
581 
582 	if (dmac_int & TSI721_DMAC_INT_ERR) {
583 		int i = 10000;
584 		struct tsi721_tx_desc *desc;
585 
586 		desc = bdma_chan->active_tx;
587 		dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
588 		tsi_err(&bdma_chan->dchan.dev->device,
589 			"DMAC%d_STS = 0x%x did=%d raddr=0x%llx",
590 			bdma_chan->id, dmac_sts, desc->destid, desc->rio_addr);
591 
592 		/* Re-initialize DMA channel if possible */
593 
594 		if ((dmac_sts & TSI721_DMAC_STS_ABORT) == 0)
595 			goto err_out;
596 
597 		tsi721_clr_stat(bdma_chan);
598 
599 		spin_lock(&bdma_chan->lock);
600 
601 		/* Put DMA channel into init state */
602 		iowrite32(TSI721_DMAC_CTL_INIT,
603 			  bdma_chan->regs + TSI721_DMAC_CTL);
604 		do {
605 			udelay(1);
606 			dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
607 			i--;
608 		} while ((dmac_sts & TSI721_DMAC_STS_ABORT) && i);
609 
610 		if (dmac_sts & TSI721_DMAC_STS_ABORT) {
611 			tsi_err(&bdma_chan->dchan.dev->device,
612 				"Failed to re-initiate DMAC%d",	bdma_chan->id);
613 			spin_unlock(&bdma_chan->lock);
614 			goto err_out;
615 		}
616 
617 		/* Setup DMA descriptor pointers */
618 		iowrite32(((u64)bdma_chan->bd_phys >> 32),
619 			bdma_chan->regs + TSI721_DMAC_DPTRH);
620 		iowrite32(((u64)bdma_chan->bd_phys & TSI721_DMAC_DPTRL_MASK),
621 			bdma_chan->regs + TSI721_DMAC_DPTRL);
622 
623 		/* Setup descriptor status FIFO */
624 		iowrite32(((u64)bdma_chan->sts_phys >> 32),
625 			bdma_chan->regs + TSI721_DMAC_DSBH);
626 		iowrite32(((u64)bdma_chan->sts_phys & TSI721_DMAC_DSBL_MASK),
627 			bdma_chan->regs + TSI721_DMAC_DSBL);
628 		iowrite32(TSI721_DMAC_DSSZ_SIZE(bdma_chan->sts_size),
629 			bdma_chan->regs + TSI721_DMAC_DSSZ);
630 
631 		/* Clear interrupt bits */
632 		iowrite32(TSI721_DMAC_INT_ALL,
633 			bdma_chan->regs + TSI721_DMAC_INT);
634 
635 		ioread32(bdma_chan->regs + TSI721_DMAC_INT);
636 
637 		bdma_chan->wr_count = bdma_chan->wr_count_next = 0;
638 		bdma_chan->sts_rdptr = 0;
639 		udelay(10);
640 
641 		desc = bdma_chan->active_tx;
642 		desc->status = DMA_ERROR;
643 		dma_cookie_complete(&desc->txd);
644 		list_add(&desc->desc_node, &bdma_chan->free_list);
645 		bdma_chan->active_tx = NULL;
646 		if (bdma_chan->active)
647 			tsi721_advance_work(bdma_chan, NULL);
648 		spin_unlock(&bdma_chan->lock);
649 	}
650 
651 	if (dmac_int & TSI721_DMAC_INT_STFULL) {
652 		tsi_err(&bdma_chan->dchan.dev->device,
653 			"DMAC%d descriptor status FIFO is full",
654 			bdma_chan->id);
655 	}
656 
657 	if (dmac_int & (TSI721_DMAC_INT_DONE | TSI721_DMAC_INT_IOFDONE)) {
658 		struct tsi721_tx_desc *desc;
659 
660 		tsi721_clr_stat(bdma_chan);
661 		spin_lock(&bdma_chan->lock);
662 		desc = bdma_chan->active_tx;
663 
664 		if (desc->sg_len == 0) {
665 			dma_async_tx_callback callback = NULL;
666 			void *param = NULL;
667 
668 			desc->status = DMA_COMPLETE;
669 			dma_cookie_complete(&desc->txd);
670 			if (desc->txd.flags & DMA_PREP_INTERRUPT) {
671 				callback = desc->txd.callback;
672 				param = desc->txd.callback_param;
673 			}
674 			list_add(&desc->desc_node, &bdma_chan->free_list);
675 			bdma_chan->active_tx = NULL;
676 			if (bdma_chan->active)
677 				tsi721_advance_work(bdma_chan, NULL);
678 			spin_unlock(&bdma_chan->lock);
679 			if (callback)
680 				callback(param);
681 		} else {
682 			if (bdma_chan->active)
683 				tsi721_advance_work(bdma_chan,
684 						    bdma_chan->active_tx);
685 			spin_unlock(&bdma_chan->lock);
686 		}
687 	}
688 err_out:
689 	/* Re-Enable BDMA channel interrupts */
690 	iowrite32(TSI721_DMAC_INT_ALL, bdma_chan->regs + TSI721_DMAC_INTE);
691 }
692 
693 static dma_cookie_t tsi721_tx_submit(struct dma_async_tx_descriptor *txd)
694 {
695 	struct tsi721_tx_desc *desc = to_tsi721_desc(txd);
696 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(txd->chan);
697 	dma_cookie_t cookie;
698 
699 	/* Check if the descriptor is detached from any lists */
700 	if (!list_empty(&desc->desc_node)) {
701 		tsi_err(&bdma_chan->dchan.dev->device,
702 			"DMAC%d wrong state of descriptor %p",
703 			bdma_chan->id, txd);
704 		return -EIO;
705 	}
706 
707 	spin_lock_bh(&bdma_chan->lock);
708 
709 	if (!bdma_chan->active) {
710 		spin_unlock_bh(&bdma_chan->lock);
711 		return -ENODEV;
712 	}
713 
714 	cookie = dma_cookie_assign(txd);
715 	desc->status = DMA_IN_PROGRESS;
716 	list_add_tail(&desc->desc_node, &bdma_chan->queue);
717 	tsi721_advance_work(bdma_chan, NULL);
718 
719 	spin_unlock_bh(&bdma_chan->lock);
720 	return cookie;
721 }
722 
723 static int tsi721_alloc_chan_resources(struct dma_chan *dchan)
724 {
725 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
726 	struct tsi721_tx_desc *desc;
727 	int i;
728 
729 	tsi_debug(DMA, &dchan->dev->device, "DMAC%d", bdma_chan->id);
730 
731 	if (bdma_chan->bd_base)
732 		return dma_txqueue_sz;
733 
734 	/* Initialize BDMA channel */
735 	if (tsi721_bdma_ch_init(bdma_chan, dma_desc_per_channel)) {
736 		tsi_err(&dchan->dev->device, "Unable to initialize DMAC%d",
737 			bdma_chan->id);
738 		return -ENODEV;
739 	}
740 
741 	/* Allocate queue of transaction descriptors */
742 	desc = kcalloc(dma_txqueue_sz, sizeof(struct tsi721_tx_desc),
743 			GFP_ATOMIC);
744 	if (!desc) {
745 		tsi721_bdma_ch_free(bdma_chan);
746 		return -ENOMEM;
747 	}
748 
749 	bdma_chan->tx_desc = desc;
750 
751 	for (i = 0; i < dma_txqueue_sz; i++) {
752 		dma_async_tx_descriptor_init(&desc[i].txd, dchan);
753 		desc[i].txd.tx_submit = tsi721_tx_submit;
754 		desc[i].txd.flags = DMA_CTRL_ACK;
755 		list_add(&desc[i].desc_node, &bdma_chan->free_list);
756 	}
757 
758 	dma_cookie_init(dchan);
759 
760 	bdma_chan->active = true;
761 	tsi721_bdma_interrupt_enable(bdma_chan, 1);
762 
763 	return dma_txqueue_sz;
764 }
765 
766 static void tsi721_sync_dma_irq(struct tsi721_bdma_chan *bdma_chan)
767 {
768 	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
769 
770 #ifdef CONFIG_PCI_MSI
771 	if (priv->flags & TSI721_USING_MSIX) {
772 		synchronize_irq(priv->msix[TSI721_VECT_DMA0_DONE +
773 					   bdma_chan->id].vector);
774 		synchronize_irq(priv->msix[TSI721_VECT_DMA0_INT +
775 					   bdma_chan->id].vector);
776 	} else
777 #endif
778 	synchronize_irq(priv->pdev->irq);
779 }
780 
781 static void tsi721_free_chan_resources(struct dma_chan *dchan)
782 {
783 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
784 
785 	tsi_debug(DMA, &dchan->dev->device, "DMAC%d", bdma_chan->id);
786 
787 	if (!bdma_chan->bd_base)
788 		return;
789 
790 	tsi721_bdma_interrupt_enable(bdma_chan, 0);
791 	bdma_chan->active = false;
792 	tsi721_sync_dma_irq(bdma_chan);
793 	tasklet_kill(&bdma_chan->tasklet);
794 	INIT_LIST_HEAD(&bdma_chan->free_list);
795 	kfree(bdma_chan->tx_desc);
796 	tsi721_bdma_ch_free(bdma_chan);
797 }
798 
799 static
800 enum dma_status tsi721_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
801 				 struct dma_tx_state *txstate)
802 {
803 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
804 	enum dma_status	status;
805 
806 	spin_lock_bh(&bdma_chan->lock);
807 	status = dma_cookie_status(dchan, cookie, txstate);
808 	spin_unlock_bh(&bdma_chan->lock);
809 	return status;
810 }
811 
812 static void tsi721_issue_pending(struct dma_chan *dchan)
813 {
814 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
815 
816 	tsi_debug(DMA, &dchan->dev->device, "DMAC%d", bdma_chan->id);
817 
818 	spin_lock_bh(&bdma_chan->lock);
819 	if (tsi721_dma_is_idle(bdma_chan) && bdma_chan->active) {
820 		tsi721_advance_work(bdma_chan, NULL);
821 	}
822 	spin_unlock_bh(&bdma_chan->lock);
823 }
824 
825 static
826 struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
827 			struct scatterlist *sgl, unsigned int sg_len,
828 			enum dma_transfer_direction dir, unsigned long flags,
829 			void *tinfo)
830 {
831 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
832 	struct tsi721_tx_desc *desc;
833 	struct rio_dma_ext *rext = tinfo;
834 	enum dma_rtype rtype;
835 	struct dma_async_tx_descriptor *txd = NULL;
836 
837 	if (!sgl || !sg_len) {
838 		tsi_err(&dchan->dev->device, "DMAC%d No SG list",
839 			bdma_chan->id);
840 		return ERR_PTR(-EINVAL);
841 	}
842 
843 	tsi_debug(DMA, &dchan->dev->device, "DMAC%d %s", bdma_chan->id,
844 		  (dir == DMA_DEV_TO_MEM)?"READ":"WRITE");
845 
846 	if (dir == DMA_DEV_TO_MEM)
847 		rtype = NREAD;
848 	else if (dir == DMA_MEM_TO_DEV) {
849 		switch (rext->wr_type) {
850 		case RDW_ALL_NWRITE:
851 			rtype = ALL_NWRITE;
852 			break;
853 		case RDW_ALL_NWRITE_R:
854 			rtype = ALL_NWRITE_R;
855 			break;
856 		case RDW_LAST_NWRITE_R:
857 		default:
858 			rtype = LAST_NWRITE_R;
859 			break;
860 		}
861 	} else {
862 		tsi_err(&dchan->dev->device,
863 			"DMAC%d Unsupported DMA direction option",
864 			bdma_chan->id);
865 		return ERR_PTR(-EINVAL);
866 	}
867 
868 	spin_lock_bh(&bdma_chan->lock);
869 
870 	if (!list_empty(&bdma_chan->free_list)) {
871 		desc = list_first_entry(&bdma_chan->free_list,
872 				struct tsi721_tx_desc, desc_node);
873 		list_del_init(&desc->desc_node);
874 		desc->destid = rext->destid;
875 		desc->rio_addr = rext->rio_addr;
876 		desc->rio_addr_u = 0;
877 		desc->rtype = rtype;
878 		desc->sg_len	= sg_len;
879 		desc->sg	= sgl;
880 		txd		= &desc->txd;
881 		txd->flags	= flags;
882 	}
883 
884 	spin_unlock_bh(&bdma_chan->lock);
885 
886 	if (!txd) {
887 		tsi_debug(DMA, &dchan->dev->device,
888 			  "DMAC%d free TXD is not available", bdma_chan->id);
889 		return ERR_PTR(-EBUSY);
890 	}
891 
892 	return txd;
893 }
894 
895 static int tsi721_terminate_all(struct dma_chan *dchan)
896 {
897 	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
898 	struct tsi721_tx_desc *desc, *_d;
899 	LIST_HEAD(list);
900 
901 	tsi_debug(DMA, &dchan->dev->device, "DMAC%d", bdma_chan->id);
902 
903 	spin_lock_bh(&bdma_chan->lock);
904 
905 	bdma_chan->active = false;
906 
907 	while (!tsi721_dma_is_idle(bdma_chan)) {
908 
909 		udelay(5);
910 #if (0)
911 		/* make sure to stop the transfer */
912 		iowrite32(TSI721_DMAC_CTL_SUSP,
913 			  bdma_chan->regs + TSI721_DMAC_CTL);
914 
915 		/* Wait until DMA channel stops */
916 		do {
917 			dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
918 		} while ((dmac_int & TSI721_DMAC_INT_SUSP) == 0);
919 #endif
920 	}
921 
922 	if (bdma_chan->active_tx)
923 		list_add(&bdma_chan->active_tx->desc_node, &list);
924 	list_splice_init(&bdma_chan->queue, &list);
925 
926 	list_for_each_entry_safe(desc, _d, &list, desc_node)
927 		tsi721_dma_tx_err(bdma_chan, desc);
928 
929 	spin_unlock_bh(&bdma_chan->lock);
930 
931 	return 0;
932 }
933 
934 static void tsi721_dma_stop(struct tsi721_bdma_chan *bdma_chan)
935 {
936 	if (!bdma_chan->active)
937 		return;
938 	spin_lock_bh(&bdma_chan->lock);
939 	if (!tsi721_dma_is_idle(bdma_chan)) {
940 		int timeout = 100000;
941 
942 		/* stop the transfer in progress */
943 		iowrite32(TSI721_DMAC_CTL_SUSP,
944 			  bdma_chan->regs + TSI721_DMAC_CTL);
945 
946 		/* Wait until DMA channel stops */
947 		while (!tsi721_dma_is_idle(bdma_chan) && --timeout)
948 			udelay(1);
949 	}
950 
951 	spin_unlock_bh(&bdma_chan->lock);
952 }
953 
954 void tsi721_dma_stop_all(struct tsi721_device *priv)
955 {
956 	int i;
957 
958 	for (i = 0; i < TSI721_DMA_MAXCH; i++) {
959 		if ((i != TSI721_DMACH_MAINT) && (dma_sel & (1 << i)))
960 			tsi721_dma_stop(&priv->bdma[i]);
961 	}
962 }
963 
964 int tsi721_register_dma(struct tsi721_device *priv)
965 {
966 	int i;
967 	int nr_channels = 0;
968 	int err;
969 	struct rio_mport *mport = &priv->mport;
970 
971 	INIT_LIST_HEAD(&mport->dma.channels);
972 
973 	for (i = 0; i < TSI721_DMA_MAXCH; i++) {
974 		struct tsi721_bdma_chan *bdma_chan = &priv->bdma[i];
975 
976 		if ((i == TSI721_DMACH_MAINT) || (dma_sel & (1 << i)) == 0)
977 			continue;
978 
979 		bdma_chan->regs = priv->regs + TSI721_DMAC_BASE(i);
980 
981 		bdma_chan->dchan.device = &mport->dma;
982 		bdma_chan->dchan.cookie = 1;
983 		bdma_chan->dchan.chan_id = i;
984 		bdma_chan->id = i;
985 		bdma_chan->active = false;
986 
987 		spin_lock_init(&bdma_chan->lock);
988 
989 		bdma_chan->active_tx = NULL;
990 		INIT_LIST_HEAD(&bdma_chan->queue);
991 		INIT_LIST_HEAD(&bdma_chan->free_list);
992 
993 		tasklet_init(&bdma_chan->tasklet, tsi721_dma_tasklet,
994 			     (unsigned long)bdma_chan);
995 		list_add_tail(&bdma_chan->dchan.device_node,
996 			      &mport->dma.channels);
997 		nr_channels++;
998 	}
999 
1000 	mport->dma.chancnt = nr_channels;
1001 	dma_cap_zero(mport->dma.cap_mask);
1002 	dma_cap_set(DMA_PRIVATE, mport->dma.cap_mask);
1003 	dma_cap_set(DMA_SLAVE, mport->dma.cap_mask);
1004 
1005 	mport->dma.dev = &priv->pdev->dev;
1006 	mport->dma.device_alloc_chan_resources = tsi721_alloc_chan_resources;
1007 	mport->dma.device_free_chan_resources = tsi721_free_chan_resources;
1008 	mport->dma.device_tx_status = tsi721_tx_status;
1009 	mport->dma.device_issue_pending = tsi721_issue_pending;
1010 	mport->dma.device_prep_slave_sg = tsi721_prep_rio_sg;
1011 	mport->dma.device_terminate_all = tsi721_terminate_all;
1012 
1013 	err = dma_async_device_register(&mport->dma);
1014 	if (err)
1015 		tsi_err(&priv->pdev->dev, "Failed to register DMA device");
1016 
1017 	return err;
1018 }
1019 
1020 void tsi721_unregister_dma(struct tsi721_device *priv)
1021 {
1022 	struct rio_mport *mport = &priv->mport;
1023 	struct dma_chan *chan, *_c;
1024 	struct tsi721_bdma_chan *bdma_chan;
1025 
1026 	tsi721_dma_stop_all(priv);
1027 	dma_async_device_unregister(&mport->dma);
1028 
1029 	list_for_each_entry_safe(chan, _c, &mport->dma.channels,
1030 					device_node) {
1031 		bdma_chan = to_tsi721_chan(chan);
1032 		if (bdma_chan->active) {
1033 			tsi721_bdma_interrupt_enable(bdma_chan, 0);
1034 			bdma_chan->active = false;
1035 			tsi721_sync_dma_irq(bdma_chan);
1036 			tasklet_kill(&bdma_chan->tasklet);
1037 			INIT_LIST_HEAD(&bdma_chan->free_list);
1038 			kfree(bdma_chan->tx_desc);
1039 			tsi721_bdma_ch_free(bdma_chan);
1040 		}
1041 
1042 		list_del(&chan->device_node);
1043 	}
1044 }
1045