1/*
2 * DMA Engine support for Tsi721 PCIExpress-to-SRIO bridge
3 *
4 * Copyright (c) 2011-2014 Integrated Device Technology, Inc.
5 * Alexandre Bounine <alexandre.bounine@idt.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15 * more details.
16 *
17 * The full GNU General Public License is included in this distribution in the
18 * file called COPYING.
19 */
20
21#include <linux/io.h>
22#include <linux/errno.h>
23#include <linux/init.h>
24#include <linux/ioport.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/pci.h>
28#include <linux/rio.h>
29#include <linux/rio_drv.h>
30#include <linux/dma-mapping.h>
31#include <linux/interrupt.h>
32#include <linux/kfifo.h>
33#include <linux/delay.h>
34#include "../../dma/dmaengine.h"
35
36#include "tsi721.h"
37
38#define TSI721_DMA_TX_QUEUE_SZ	16	/* number of transaction descriptors */
39
40#ifdef CONFIG_PCI_MSI
41static irqreturn_t tsi721_bdma_msix(int irq, void *ptr);
42#endif
43static int tsi721_submit_sg(struct tsi721_tx_desc *desc);
44
45static unsigned int dma_desc_per_channel = 128;
46module_param(dma_desc_per_channel, uint, S_IWUSR | S_IRUGO);
47MODULE_PARM_DESC(dma_desc_per_channel,
48		 "Number of DMA descriptors per channel (default: 128)");
49
50static inline struct tsi721_bdma_chan *to_tsi721_chan(struct dma_chan *chan)
51{
52	return container_of(chan, struct tsi721_bdma_chan, dchan);
53}
54
55static inline struct tsi721_device *to_tsi721(struct dma_device *ddev)
56{
57	return container_of(ddev, struct rio_mport, dma)->priv;
58}
59
60static inline
61struct tsi721_tx_desc *to_tsi721_desc(struct dma_async_tx_descriptor *txd)
62{
63	return container_of(txd, struct tsi721_tx_desc, txd);
64}
65
66static inline
67struct tsi721_tx_desc *tsi721_dma_first_active(
68				struct tsi721_bdma_chan *bdma_chan)
69{
70	return list_first_entry(&bdma_chan->active_list,
71				struct tsi721_tx_desc, desc_node);
72}
73
74static int tsi721_bdma_ch_init(struct tsi721_bdma_chan *bdma_chan, int bd_num)
75{
76	struct tsi721_dma_desc *bd_ptr;
77	struct device *dev = bdma_chan->dchan.device->dev;
78	u64		*sts_ptr;
79	dma_addr_t	bd_phys;
80	dma_addr_t	sts_phys;
81	int		sts_size;
82#ifdef CONFIG_PCI_MSI
83	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
84#endif
85
86	dev_dbg(dev, "Init Block DMA Engine, CH%d\n", bdma_chan->id);
87
88	/*
89	 * Allocate space for DMA descriptors
90	 * (add an extra element for link descriptor)
91	 */
92	bd_ptr = dma_zalloc_coherent(dev,
93				(bd_num + 1) * sizeof(struct tsi721_dma_desc),
94				&bd_phys, GFP_KERNEL);
95	if (!bd_ptr)
96		return -ENOMEM;
97
98	bdma_chan->bd_num = bd_num;
99	bdma_chan->bd_phys = bd_phys;
100	bdma_chan->bd_base = bd_ptr;
101
102	dev_dbg(dev, "DMA descriptors @ %p (phys = %llx)\n",
103		bd_ptr, (unsigned long long)bd_phys);
104
105	/* Allocate space for descriptor status FIFO */
106	sts_size = ((bd_num + 1) >= TSI721_DMA_MINSTSSZ) ?
107					(bd_num + 1) : TSI721_DMA_MINSTSSZ;
108	sts_size = roundup_pow_of_two(sts_size);
109	sts_ptr = dma_zalloc_coherent(dev,
110				     sts_size * sizeof(struct tsi721_dma_sts),
111				     &sts_phys, GFP_KERNEL);
112	if (!sts_ptr) {
113		/* Free space allocated for DMA descriptors */
114		dma_free_coherent(dev,
115				  (bd_num + 1) * sizeof(struct tsi721_dma_desc),
116				  bd_ptr, bd_phys);
117		bdma_chan->bd_base = NULL;
118		return -ENOMEM;
119	}
120
121	bdma_chan->sts_phys = sts_phys;
122	bdma_chan->sts_base = sts_ptr;
123	bdma_chan->sts_size = sts_size;
124
125	dev_dbg(dev,
126		"desc status FIFO @ %p (phys = %llx) size=0x%x\n",
127		sts_ptr, (unsigned long long)sts_phys, sts_size);
128
129	/* Initialize DMA descriptors ring using added link descriptor */
130	bd_ptr[bd_num].type_id = cpu_to_le32(DTYPE3 << 29);
131	bd_ptr[bd_num].next_lo = cpu_to_le32((u64)bd_phys &
132						 TSI721_DMAC_DPTRL_MASK);
133	bd_ptr[bd_num].next_hi = cpu_to_le32((u64)bd_phys >> 32);
134
135	/* Setup DMA descriptor pointers */
136	iowrite32(((u64)bd_phys >> 32),
137		bdma_chan->regs + TSI721_DMAC_DPTRH);
138	iowrite32(((u64)bd_phys & TSI721_DMAC_DPTRL_MASK),
139		bdma_chan->regs + TSI721_DMAC_DPTRL);
140
141	/* Setup descriptor status FIFO */
142	iowrite32(((u64)sts_phys >> 32),
143		bdma_chan->regs + TSI721_DMAC_DSBH);
144	iowrite32(((u64)sts_phys & TSI721_DMAC_DSBL_MASK),
145		bdma_chan->regs + TSI721_DMAC_DSBL);
146	iowrite32(TSI721_DMAC_DSSZ_SIZE(sts_size),
147		bdma_chan->regs + TSI721_DMAC_DSSZ);
148
149	/* Clear interrupt bits */
150	iowrite32(TSI721_DMAC_INT_ALL,
151		bdma_chan->regs + TSI721_DMAC_INT);
152
153	ioread32(bdma_chan->regs + TSI721_DMAC_INT);
154
155#ifdef CONFIG_PCI_MSI
156	/* Request interrupt service if we are in MSI-X mode */
157	if (priv->flags & TSI721_USING_MSIX) {
158		int rc, idx;
159
160		idx = TSI721_VECT_DMA0_DONE + bdma_chan->id;
161
162		rc = request_irq(priv->msix[idx].vector, tsi721_bdma_msix, 0,
163				 priv->msix[idx].irq_name, (void *)bdma_chan);
164
165		if (rc) {
166			dev_dbg(dev, "Unable to get MSI-X for BDMA%d-DONE\n",
167				bdma_chan->id);
168			goto err_out;
169		}
170
171		idx = TSI721_VECT_DMA0_INT + bdma_chan->id;
172
173		rc = request_irq(priv->msix[idx].vector, tsi721_bdma_msix, 0,
174				priv->msix[idx].irq_name, (void *)bdma_chan);
175
176		if (rc)	{
177			dev_dbg(dev, "Unable to get MSI-X for BDMA%d-INT\n",
178				bdma_chan->id);
179			free_irq(
180				priv->msix[TSI721_VECT_DMA0_DONE +
181					    bdma_chan->id].vector,
182				(void *)bdma_chan);
183		}
184
185err_out:
186		if (rc) {
187			/* Free space allocated for DMA descriptors */
188			dma_free_coherent(dev,
189				(bd_num + 1) * sizeof(struct tsi721_dma_desc),
190				bd_ptr, bd_phys);
191			bdma_chan->bd_base = NULL;
192
193			/* Free space allocated for status descriptors */
194			dma_free_coherent(dev,
195				sts_size * sizeof(struct tsi721_dma_sts),
196				sts_ptr, sts_phys);
197			bdma_chan->sts_base = NULL;
198
199			return -EIO;
200		}
201	}
202#endif /* CONFIG_PCI_MSI */
203
204	/* Toggle DMA channel initialization */
205	iowrite32(TSI721_DMAC_CTL_INIT,	bdma_chan->regs + TSI721_DMAC_CTL);
206	ioread32(bdma_chan->regs + TSI721_DMAC_CTL);
207	bdma_chan->wr_count = bdma_chan->wr_count_next = 0;
208	bdma_chan->sts_rdptr = 0;
209	udelay(10);
210
211	return 0;
212}
213
214static int tsi721_bdma_ch_free(struct tsi721_bdma_chan *bdma_chan)
215{
216	u32 ch_stat;
217#ifdef CONFIG_PCI_MSI
218	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
219#endif
220
221	if (bdma_chan->bd_base == NULL)
222		return 0;
223
224	/* Check if DMA channel still running */
225	ch_stat = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
226	if (ch_stat & TSI721_DMAC_STS_RUN)
227		return -EFAULT;
228
229	/* Put DMA channel into init state */
230	iowrite32(TSI721_DMAC_CTL_INIT,	bdma_chan->regs + TSI721_DMAC_CTL);
231
232#ifdef CONFIG_PCI_MSI
233	if (priv->flags & TSI721_USING_MSIX) {
234		free_irq(priv->msix[TSI721_VECT_DMA0_DONE +
235				    bdma_chan->id].vector, (void *)bdma_chan);
236		free_irq(priv->msix[TSI721_VECT_DMA0_INT +
237				    bdma_chan->id].vector, (void *)bdma_chan);
238	}
239#endif /* CONFIG_PCI_MSI */
240
241	/* Free space allocated for DMA descriptors */
242	dma_free_coherent(bdma_chan->dchan.device->dev,
243		(bdma_chan->bd_num + 1) * sizeof(struct tsi721_dma_desc),
244		bdma_chan->bd_base, bdma_chan->bd_phys);
245	bdma_chan->bd_base = NULL;
246
247	/* Free space allocated for status FIFO */
248	dma_free_coherent(bdma_chan->dchan.device->dev,
249		bdma_chan->sts_size * sizeof(struct tsi721_dma_sts),
250		bdma_chan->sts_base, bdma_chan->sts_phys);
251	bdma_chan->sts_base = NULL;
252	return 0;
253}
254
255static void
256tsi721_bdma_interrupt_enable(struct tsi721_bdma_chan *bdma_chan, int enable)
257{
258	if (enable) {
259		/* Clear pending BDMA channel interrupts */
260		iowrite32(TSI721_DMAC_INT_ALL,
261			bdma_chan->regs + TSI721_DMAC_INT);
262		ioread32(bdma_chan->regs + TSI721_DMAC_INT);
263		/* Enable BDMA channel interrupts */
264		iowrite32(TSI721_DMAC_INT_ALL,
265			bdma_chan->regs + TSI721_DMAC_INTE);
266	} else {
267		/* Disable BDMA channel interrupts */
268		iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
269		/* Clear pending BDMA channel interrupts */
270		iowrite32(TSI721_DMAC_INT_ALL,
271			bdma_chan->regs + TSI721_DMAC_INT);
272	}
273
274}
275
276static bool tsi721_dma_is_idle(struct tsi721_bdma_chan *bdma_chan)
277{
278	u32 sts;
279
280	sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
281	return ((sts & TSI721_DMAC_STS_RUN) == 0);
282}
283
284void tsi721_bdma_handler(struct tsi721_bdma_chan *bdma_chan)
285{
286	/* Disable BDMA channel interrupts */
287	iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
288	if (bdma_chan->active)
289		tasklet_schedule(&bdma_chan->tasklet);
290}
291
292#ifdef CONFIG_PCI_MSI
293/**
294 * tsi721_omsg_msix - MSI-X interrupt handler for BDMA channels
295 * @irq: Linux interrupt number
296 * @ptr: Pointer to interrupt-specific data (BDMA channel structure)
297 *
298 * Handles BDMA channel interrupts signaled using MSI-X.
299 */
300static irqreturn_t tsi721_bdma_msix(int irq, void *ptr)
301{
302	struct tsi721_bdma_chan *bdma_chan = ptr;
303
304	tsi721_bdma_handler(bdma_chan);
305	return IRQ_HANDLED;
306}
307#endif /* CONFIG_PCI_MSI */
308
309/* Must be called with the spinlock held */
310static void tsi721_start_dma(struct tsi721_bdma_chan *bdma_chan)
311{
312	if (!tsi721_dma_is_idle(bdma_chan)) {
313		dev_err(bdma_chan->dchan.device->dev,
314			"BUG: Attempt to start non-idle channel\n");
315		return;
316	}
317
318	if (bdma_chan->wr_count == bdma_chan->wr_count_next) {
319		dev_err(bdma_chan->dchan.device->dev,
320			"BUG: Attempt to start DMA with no BDs ready\n");
321		return;
322	}
323
324	dev_dbg(bdma_chan->dchan.device->dev,
325		"%s: chan_%d (wrc=%d)\n", __func__, bdma_chan->id,
326		bdma_chan->wr_count_next);
327
328	iowrite32(bdma_chan->wr_count_next,
329		bdma_chan->regs + TSI721_DMAC_DWRCNT);
330	ioread32(bdma_chan->regs + TSI721_DMAC_DWRCNT);
331
332	bdma_chan->wr_count = bdma_chan->wr_count_next;
333}
334
335static int
336tsi721_desc_fill_init(struct tsi721_tx_desc *desc,
337		      struct tsi721_dma_desc *bd_ptr,
338		      struct scatterlist *sg, u32 sys_size)
339{
340	u64 rio_addr;
341
342	if (bd_ptr == NULL)
343		return -EINVAL;
344
345	/* Initialize DMA descriptor */
346	bd_ptr->type_id = cpu_to_le32((DTYPE1 << 29) |
347				      (desc->rtype << 19) | desc->destid);
348	bd_ptr->bcount = cpu_to_le32(((desc->rio_addr & 0x3) << 30) |
349				     (sys_size << 26));
350	rio_addr = (desc->rio_addr >> 2) |
351				((u64)(desc->rio_addr_u & 0x3) << 62);
352	bd_ptr->raddr_lo = cpu_to_le32(rio_addr & 0xffffffff);
353	bd_ptr->raddr_hi = cpu_to_le32(rio_addr >> 32);
354	bd_ptr->t1.bufptr_lo = cpu_to_le32(
355					(u64)sg_dma_address(sg) & 0xffffffff);
356	bd_ptr->t1.bufptr_hi = cpu_to_le32((u64)sg_dma_address(sg) >> 32);
357	bd_ptr->t1.s_dist = 0;
358	bd_ptr->t1.s_size = 0;
359
360	return 0;
361}
362
363static int
364tsi721_desc_fill_end(struct tsi721_dma_desc *bd_ptr, u32 bcount, bool interrupt)
365{
366	if (bd_ptr == NULL)
367		return -EINVAL;
368
369	/* Update DMA descriptor */
370	if (interrupt)
371		bd_ptr->type_id |= cpu_to_le32(TSI721_DMAD_IOF);
372	bd_ptr->bcount |= cpu_to_le32(bcount & TSI721_DMAD_BCOUNT1);
373
374	return 0;
375}
376
377static void tsi721_dma_tx_err(struct tsi721_bdma_chan *bdma_chan,
378			      struct tsi721_tx_desc *desc)
379{
380	struct dma_async_tx_descriptor *txd = &desc->txd;
381	dma_async_tx_callback callback = txd->callback;
382	void *param = txd->callback_param;
383
384	list_move(&desc->desc_node, &bdma_chan->free_list);
385
386	if (callback)
387		callback(param);
388}
389
390static void tsi721_clr_stat(struct tsi721_bdma_chan *bdma_chan)
391{
392	u32 srd_ptr;
393	u64 *sts_ptr;
394	int i, j;
395
396	/* Check and clear descriptor status FIFO entries */
397	srd_ptr = bdma_chan->sts_rdptr;
398	sts_ptr = bdma_chan->sts_base;
399	j = srd_ptr * 8;
400	while (sts_ptr[j]) {
401		for (i = 0; i < 8 && sts_ptr[j]; i++, j++)
402			sts_ptr[j] = 0;
403
404		++srd_ptr;
405		srd_ptr %= bdma_chan->sts_size;
406		j = srd_ptr * 8;
407	}
408
409	iowrite32(srd_ptr, bdma_chan->regs + TSI721_DMAC_DSRP);
410	bdma_chan->sts_rdptr = srd_ptr;
411}
412
413/* Must be called with the channel spinlock held */
414static int tsi721_submit_sg(struct tsi721_tx_desc *desc)
415{
416	struct dma_chan *dchan = desc->txd.chan;
417	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
418	u32 sys_size;
419	u64 rio_addr;
420	dma_addr_t next_addr;
421	u32 bcount;
422	struct scatterlist *sg;
423	unsigned int i;
424	int err = 0;
425	struct tsi721_dma_desc *bd_ptr = NULL;
426	u32 idx, rd_idx;
427	u32 add_count = 0;
428
429	if (!tsi721_dma_is_idle(bdma_chan)) {
430		dev_err(bdma_chan->dchan.device->dev,
431			"BUG: Attempt to use non-idle channel\n");
432		return -EIO;
433	}
434
435	/*
436	 * Fill DMA channel's hardware buffer descriptors.
437	 * (NOTE: RapidIO destination address is limited to 64 bits for now)
438	 */
439	rio_addr = desc->rio_addr;
440	next_addr = -1;
441	bcount = 0;
442	sys_size = dma_to_mport(bdma_chan->dchan.device)->sys_size;
443
444	rd_idx = ioread32(bdma_chan->regs + TSI721_DMAC_DRDCNT);
445	rd_idx %= (bdma_chan->bd_num + 1);
446
447	idx = bdma_chan->wr_count_next % (bdma_chan->bd_num + 1);
448	if (idx == bdma_chan->bd_num) {
449		/* wrap around link descriptor */
450		idx = 0;
451		add_count++;
452	}
453
454	dev_dbg(dchan->device->dev, "%s: BD ring status: rdi=%d wri=%d\n",
455		__func__, rd_idx, idx);
456
457	for_each_sg(desc->sg, sg, desc->sg_len, i) {
458
459		dev_dbg(dchan->device->dev, "sg%d/%d addr: 0x%llx len: %d\n",
460			i, desc->sg_len,
461			(unsigned long long)sg_dma_address(sg), sg_dma_len(sg));
462
463		if (sg_dma_len(sg) > TSI721_BDMA_MAX_BCOUNT) {
464			dev_err(dchan->device->dev,
465				"%s: SG entry %d is too large\n", __func__, i);
466			err = -EINVAL;
467			break;
468		}
469
470		/*
471		 * If this sg entry forms contiguous block with previous one,
472		 * try to merge it into existing DMA descriptor
473		 */
474		if (next_addr == sg_dma_address(sg) &&
475		    bcount + sg_dma_len(sg) <= TSI721_BDMA_MAX_BCOUNT) {
476			/* Adjust byte count of the descriptor */
477			bcount += sg_dma_len(sg);
478			goto entry_done;
479		} else if (next_addr != -1) {
480			/* Finalize descriptor using total byte count value */
481			tsi721_desc_fill_end(bd_ptr, bcount, 0);
482			dev_dbg(dchan->device->dev,
483				"%s: prev desc final len: %d\n",
484				__func__, bcount);
485		}
486
487		desc->rio_addr = rio_addr;
488
489		if (i && idx == rd_idx) {
490			dev_dbg(dchan->device->dev,
491				"%s: HW descriptor ring is full @ %d\n",
492				__func__, i);
493			desc->sg = sg;
494			desc->sg_len -= i;
495			break;
496		}
497
498		bd_ptr = &((struct tsi721_dma_desc *)bdma_chan->bd_base)[idx];
499		err = tsi721_desc_fill_init(desc, bd_ptr, sg, sys_size);
500		if (err) {
501			dev_err(dchan->device->dev,
502				"Failed to build desc: err=%d\n", err);
503			break;
504		}
505
506		dev_dbg(dchan->device->dev, "bd_ptr = %p did=%d raddr=0x%llx\n",
507			bd_ptr, desc->destid, desc->rio_addr);
508
509		next_addr = sg_dma_address(sg);
510		bcount = sg_dma_len(sg);
511
512		add_count++;
513		if (++idx == bdma_chan->bd_num) {
514			/* wrap around link descriptor */
515			idx = 0;
516			add_count++;
517		}
518
519entry_done:
520		if (sg_is_last(sg)) {
521			tsi721_desc_fill_end(bd_ptr, bcount, 0);
522			dev_dbg(dchan->device->dev, "%s: last desc final len: %d\n",
523				__func__, bcount);
524			desc->sg_len = 0;
525		} else {
526			rio_addr += sg_dma_len(sg);
527			next_addr += sg_dma_len(sg);
528		}
529	}
530
531	if (!err)
532		bdma_chan->wr_count_next += add_count;
533
534	return err;
535}
536
537static void tsi721_advance_work(struct tsi721_bdma_chan *bdma_chan)
538{
539	struct tsi721_tx_desc *desc;
540	int err;
541
542	dev_dbg(bdma_chan->dchan.device->dev, "%s: Enter\n", __func__);
543
544	/*
545	 * If there are any new transactions in the queue add them
546	 * into the processing list
547	 */
548	if (!list_empty(&bdma_chan->queue))
549		list_splice_init(&bdma_chan->queue, &bdma_chan->active_list);
550
551	/* Start new transaction (if available) */
552	if (!list_empty(&bdma_chan->active_list)) {
553		desc = tsi721_dma_first_active(bdma_chan);
554		err = tsi721_submit_sg(desc);
555		if (!err)
556			tsi721_start_dma(bdma_chan);
557		else {
558			tsi721_dma_tx_err(bdma_chan, desc);
559			dev_dbg(bdma_chan->dchan.device->dev,
560				"ERR: tsi721_submit_sg failed with err=%d\n",
561				err);
562		}
563	}
564
565	dev_dbg(bdma_chan->dchan.device->dev, "%s: Exit\n", __func__);
566}
567
568static void tsi721_dma_tasklet(unsigned long data)
569{
570	struct tsi721_bdma_chan *bdma_chan = (struct tsi721_bdma_chan *)data;
571	u32 dmac_int, dmac_sts;
572
573	dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
574	dev_dbg(bdma_chan->dchan.device->dev, "%s: DMAC%d_INT = 0x%x\n",
575		__func__, bdma_chan->id, dmac_int);
576	/* Clear channel interrupts */
577	iowrite32(dmac_int, bdma_chan->regs + TSI721_DMAC_INT);
578
579	if (dmac_int & TSI721_DMAC_INT_ERR) {
580		dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
581		dev_err(bdma_chan->dchan.device->dev,
582			"%s: DMA ERROR - DMAC%d_STS = 0x%x\n",
583			__func__, bdma_chan->id, dmac_sts);
584	}
585
586	if (dmac_int & TSI721_DMAC_INT_STFULL) {
587		dev_err(bdma_chan->dchan.device->dev,
588			"%s: DMAC%d descriptor status FIFO is full\n",
589			__func__, bdma_chan->id);
590	}
591
592	if (dmac_int & (TSI721_DMAC_INT_DONE | TSI721_DMAC_INT_IOFDONE)) {
593		struct tsi721_tx_desc *desc;
594
595		tsi721_clr_stat(bdma_chan);
596		spin_lock(&bdma_chan->lock);
597		desc = tsi721_dma_first_active(bdma_chan);
598
599		if (desc->sg_len == 0) {
600			dma_async_tx_callback callback = NULL;
601			void *param = NULL;
602
603			desc->status = DMA_COMPLETE;
604			dma_cookie_complete(&desc->txd);
605			if (desc->txd.flags & DMA_PREP_INTERRUPT) {
606				callback = desc->txd.callback;
607				param = desc->txd.callback_param;
608			}
609			list_move(&desc->desc_node, &bdma_chan->free_list);
610			spin_unlock(&bdma_chan->lock);
611			if (callback)
612				callback(param);
613			spin_lock(&bdma_chan->lock);
614		}
615
616		tsi721_advance_work(bdma_chan);
617		spin_unlock(&bdma_chan->lock);
618	}
619
620	/* Re-Enable BDMA channel interrupts */
621	iowrite32(TSI721_DMAC_INT_ALL, bdma_chan->regs + TSI721_DMAC_INTE);
622}
623
624static dma_cookie_t tsi721_tx_submit(struct dma_async_tx_descriptor *txd)
625{
626	struct tsi721_tx_desc *desc = to_tsi721_desc(txd);
627	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(txd->chan);
628	dma_cookie_t cookie;
629
630	/* Check if the descriptor is detached from any lists */
631	if (!list_empty(&desc->desc_node)) {
632		dev_err(bdma_chan->dchan.device->dev,
633			"%s: wrong state of descriptor %p\n", __func__, txd);
634		return -EIO;
635	}
636
637	spin_lock_bh(&bdma_chan->lock);
638
639	if (!bdma_chan->active) {
640		spin_unlock_bh(&bdma_chan->lock);
641		return -ENODEV;
642	}
643
644	cookie = dma_cookie_assign(txd);
645	desc->status = DMA_IN_PROGRESS;
646	list_add_tail(&desc->desc_node, &bdma_chan->queue);
647
648	spin_unlock_bh(&bdma_chan->lock);
649	return cookie;
650}
651
652static int tsi721_alloc_chan_resources(struct dma_chan *dchan)
653{
654	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
655	struct tsi721_tx_desc *desc = NULL;
656	int i;
657
658	dev_dbg(dchan->device->dev, "%s: for channel %d\n",
659		__func__, bdma_chan->id);
660
661	if (bdma_chan->bd_base)
662		return TSI721_DMA_TX_QUEUE_SZ;
663
664	/* Initialize BDMA channel */
665	if (tsi721_bdma_ch_init(bdma_chan, dma_desc_per_channel)) {
666		dev_err(dchan->device->dev, "Unable to initialize data DMA"
667			" channel %d, aborting\n", bdma_chan->id);
668		return -ENODEV;
669	}
670
671	/* Allocate queue of transaction descriptors */
672	desc = kcalloc(TSI721_DMA_TX_QUEUE_SZ, sizeof(struct tsi721_tx_desc),
673			GFP_KERNEL);
674	if (!desc) {
675		dev_err(dchan->device->dev,
676			"Failed to allocate logical descriptors\n");
677		tsi721_bdma_ch_free(bdma_chan);
678		return -ENOMEM;
679	}
680
681	bdma_chan->tx_desc = desc;
682
683	for (i = 0; i < TSI721_DMA_TX_QUEUE_SZ; i++) {
684		dma_async_tx_descriptor_init(&desc[i].txd, dchan);
685		desc[i].txd.tx_submit = tsi721_tx_submit;
686		desc[i].txd.flags = DMA_CTRL_ACK;
687		list_add(&desc[i].desc_node, &bdma_chan->free_list);
688	}
689
690	dma_cookie_init(dchan);
691
692	bdma_chan->active = true;
693	tsi721_bdma_interrupt_enable(bdma_chan, 1);
694
695	return TSI721_DMA_TX_QUEUE_SZ;
696}
697
698static void tsi721_sync_dma_irq(struct tsi721_bdma_chan *bdma_chan)
699{
700	struct tsi721_device *priv = to_tsi721(bdma_chan->dchan.device);
701
702#ifdef CONFIG_PCI_MSI
703	if (priv->flags & TSI721_USING_MSIX) {
704		synchronize_irq(priv->msix[TSI721_VECT_DMA0_DONE +
705					   bdma_chan->id].vector);
706		synchronize_irq(priv->msix[TSI721_VECT_DMA0_INT +
707					   bdma_chan->id].vector);
708	} else
709#endif
710	synchronize_irq(priv->pdev->irq);
711}
712
713static void tsi721_free_chan_resources(struct dma_chan *dchan)
714{
715	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
716
717	dev_dbg(dchan->device->dev, "%s: for channel %d\n",
718		__func__, bdma_chan->id);
719
720	if (bdma_chan->bd_base == NULL)
721		return;
722
723	BUG_ON(!list_empty(&bdma_chan->active_list));
724	BUG_ON(!list_empty(&bdma_chan->queue));
725
726	tsi721_bdma_interrupt_enable(bdma_chan, 0);
727	bdma_chan->active = false;
728	tsi721_sync_dma_irq(bdma_chan);
729	tasklet_kill(&bdma_chan->tasklet);
730	INIT_LIST_HEAD(&bdma_chan->free_list);
731	kfree(bdma_chan->tx_desc);
732	tsi721_bdma_ch_free(bdma_chan);
733}
734
735static
736enum dma_status tsi721_tx_status(struct dma_chan *dchan, dma_cookie_t cookie,
737				 struct dma_tx_state *txstate)
738{
739	return dma_cookie_status(dchan, cookie, txstate);
740}
741
742static void tsi721_issue_pending(struct dma_chan *dchan)
743{
744	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
745
746	dev_dbg(dchan->device->dev, "%s: Enter\n", __func__);
747
748	if (tsi721_dma_is_idle(bdma_chan) && bdma_chan->active) {
749		spin_lock_bh(&bdma_chan->lock);
750		tsi721_advance_work(bdma_chan);
751		spin_unlock_bh(&bdma_chan->lock);
752	}
753}
754
755static
756struct dma_async_tx_descriptor *tsi721_prep_rio_sg(struct dma_chan *dchan,
757			struct scatterlist *sgl, unsigned int sg_len,
758			enum dma_transfer_direction dir, unsigned long flags,
759			void *tinfo)
760{
761	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
762	struct tsi721_tx_desc *desc, *_d;
763	struct rio_dma_ext *rext = tinfo;
764	enum dma_rtype rtype;
765	struct dma_async_tx_descriptor *txd = NULL;
766
767	if (!sgl || !sg_len) {
768		dev_err(dchan->device->dev, "%s: No SG list\n", __func__);
769		return NULL;
770	}
771
772	dev_dbg(dchan->device->dev, "%s: %s\n", __func__,
773		(dir == DMA_DEV_TO_MEM)?"READ":"WRITE");
774
775	if (dir == DMA_DEV_TO_MEM)
776		rtype = NREAD;
777	else if (dir == DMA_MEM_TO_DEV) {
778		switch (rext->wr_type) {
779		case RDW_ALL_NWRITE:
780			rtype = ALL_NWRITE;
781			break;
782		case RDW_ALL_NWRITE_R:
783			rtype = ALL_NWRITE_R;
784			break;
785		case RDW_LAST_NWRITE_R:
786		default:
787			rtype = LAST_NWRITE_R;
788			break;
789		}
790	} else {
791		dev_err(dchan->device->dev,
792			"%s: Unsupported DMA direction option\n", __func__);
793		return NULL;
794	}
795
796	spin_lock_bh(&bdma_chan->lock);
797
798	list_for_each_entry_safe(desc, _d, &bdma_chan->free_list, desc_node) {
799		if (async_tx_test_ack(&desc->txd)) {
800			list_del_init(&desc->desc_node);
801			desc->destid = rext->destid;
802			desc->rio_addr = rext->rio_addr;
803			desc->rio_addr_u = 0;
804			desc->rtype = rtype;
805			desc->sg_len	= sg_len;
806			desc->sg	= sgl;
807			txd		= &desc->txd;
808			txd->flags	= flags;
809			break;
810		}
811	}
812
813	spin_unlock_bh(&bdma_chan->lock);
814
815	return txd;
816}
817
818static int tsi721_terminate_all(struct dma_chan *dchan)
819{
820	struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
821	struct tsi721_tx_desc *desc, *_d;
822	u32 dmac_int;
823	LIST_HEAD(list);
824
825	dev_dbg(dchan->device->dev, "%s: Entry\n", __func__);
826
827	spin_lock_bh(&bdma_chan->lock);
828
829	bdma_chan->active = false;
830
831	if (!tsi721_dma_is_idle(bdma_chan)) {
832		/* make sure to stop the transfer */
833		iowrite32(TSI721_DMAC_CTL_SUSP,
834			  bdma_chan->regs + TSI721_DMAC_CTL);
835
836		/* Wait until DMA channel stops */
837		do {
838			dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
839		} while ((dmac_int & TSI721_DMAC_INT_SUSP) == 0);
840	}
841
842	list_splice_init(&bdma_chan->active_list, &list);
843	list_splice_init(&bdma_chan->queue, &list);
844
845	list_for_each_entry_safe(desc, _d, &list, desc_node)
846		tsi721_dma_tx_err(bdma_chan, desc);
847
848	spin_unlock_bh(&bdma_chan->lock);
849
850	return 0;
851}
852
853int tsi721_register_dma(struct tsi721_device *priv)
854{
855	int i;
856	int nr_channels = 0;
857	int err;
858	struct rio_mport *mport = priv->mport;
859
860	INIT_LIST_HEAD(&mport->dma.channels);
861
862	for (i = 0; i < TSI721_DMA_MAXCH; i++) {
863		struct tsi721_bdma_chan *bdma_chan = &priv->bdma[i];
864
865		if (i == TSI721_DMACH_MAINT)
866			continue;
867
868		bdma_chan->regs = priv->regs + TSI721_DMAC_BASE(i);
869
870		bdma_chan->dchan.device = &mport->dma;
871		bdma_chan->dchan.cookie = 1;
872		bdma_chan->dchan.chan_id = i;
873		bdma_chan->id = i;
874		bdma_chan->active = false;
875
876		spin_lock_init(&bdma_chan->lock);
877
878		INIT_LIST_HEAD(&bdma_chan->active_list);
879		INIT_LIST_HEAD(&bdma_chan->queue);
880		INIT_LIST_HEAD(&bdma_chan->free_list);
881
882		tasklet_init(&bdma_chan->tasklet, tsi721_dma_tasklet,
883			     (unsigned long)bdma_chan);
884		list_add_tail(&bdma_chan->dchan.device_node,
885			      &mport->dma.channels);
886		nr_channels++;
887	}
888
889	mport->dma.chancnt = nr_channels;
890	dma_cap_zero(mport->dma.cap_mask);
891	dma_cap_set(DMA_PRIVATE, mport->dma.cap_mask);
892	dma_cap_set(DMA_SLAVE, mport->dma.cap_mask);
893
894	mport->dma.dev = &priv->pdev->dev;
895	mport->dma.device_alloc_chan_resources = tsi721_alloc_chan_resources;
896	mport->dma.device_free_chan_resources = tsi721_free_chan_resources;
897	mport->dma.device_tx_status = tsi721_tx_status;
898	mport->dma.device_issue_pending = tsi721_issue_pending;
899	mport->dma.device_prep_slave_sg = tsi721_prep_rio_sg;
900	mport->dma.device_terminate_all = tsi721_terminate_all;
901
902	err = dma_async_device_register(&mport->dma);
903	if (err)
904		dev_err(&priv->pdev->dev, "Failed to register DMA device\n");
905
906	return err;
907}
908