[go: nahoru, domu]

dma.c revision 8722ff8cdbfac9c1b20e67bb067b455c48cb8e93
1/*
2* Filename: dma.c
3*
4*
5* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
6*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
7*
8* (C) Copyright 2013 IBM Corporation
9*
10* This program is free software; you can redistribute it and/or
11* modify it under the terms of the GNU General Public License as
12* published by the Free Software Foundation; either version 2 of the
13* License, or (at your option) any later version.
14*
15* This program is distributed in the hope that it will be useful, but
16* WITHOUT ANY WARRANTY; without even the implied warranty of
17* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18* General Public License for more details.
19*
20* You should have received a copy of the GNU General Public License
21* along with this program; if not, write to the Free Software Foundation,
22* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23*/
24
25#include "rsxx_priv.h"
26
27struct rsxx_dma {
28	struct list_head	 list;
29	u8			 cmd;
30	unsigned int		 laddr;     /* Logical address on the ramsan */
31	struct {
32		u32		 off;
33		u32		 cnt;
34	} sub_page;
35	dma_addr_t		 dma_addr;
36	struct page		 *page;
37	unsigned int		 pg_off;    /* Page Offset */
38	rsxx_dma_cb		 cb;
39	void			 *cb_data;
40};
41
42/* This timeout is used to detect a stalled DMA channel */
43#define DMA_ACTIVITY_TIMEOUT	msecs_to_jiffies(10000)
44
45struct hw_status {
46	u8	status;
47	u8	tag;
48	__le16	count;
49	__le32	_rsvd2;
50	__le64	_rsvd3;
51} __packed;
52
53enum rsxx_dma_status {
54	DMA_SW_ERR    = 0x1,
55	DMA_HW_FAULT  = 0x2,
56	DMA_CANCELLED = 0x4,
57};
58
59struct hw_cmd {
60	u8	command;
61	u8	tag;
62	u8	_rsvd;
63	u8	sub_page; /* Bit[0:2]: 512byte offset */
64			  /* Bit[4:6]: 512byte count */
65	__le32	device_addr;
66	__le64	host_addr;
67} __packed;
68
69enum rsxx_hw_cmd {
70	HW_CMD_BLK_DISCARD	= 0x70,
71	HW_CMD_BLK_WRITE	= 0x80,
72	HW_CMD_BLK_READ		= 0xC0,
73	HW_CMD_BLK_RECON_READ	= 0xE0,
74};
75
76enum rsxx_hw_status {
77	HW_STATUS_CRC		= 0x01,
78	HW_STATUS_HARD_ERR	= 0x02,
79	HW_STATUS_SOFT_ERR	= 0x04,
80	HW_STATUS_FAULT		= 0x08,
81};
82
83#define STATUS_BUFFER_SIZE8     4096
84#define COMMAND_BUFFER_SIZE8    4096
85
86static struct kmem_cache *rsxx_dma_pool;
87
88struct dma_tracker {
89	int			next_tag;
90	struct rsxx_dma	*dma;
91};
92
93#define DMA_TRACKER_LIST_SIZE8 (sizeof(struct dma_tracker_list) + \
94		(sizeof(struct dma_tracker) * RSXX_MAX_OUTSTANDING_CMDS))
95
96struct dma_tracker_list {
97	spinlock_t		lock;
98	int			head;
99	struct dma_tracker	list[0];
100};
101
102
103/*----------------- Misc Utility Functions -------------------*/
104unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card)
105{
106	unsigned long long tgt_addr8;
107
108	tgt_addr8 = ((addr8 >> card->_stripe.upper_shift) &
109		      card->_stripe.upper_mask) |
110		    ((addr8) & card->_stripe.lower_mask);
111	do_div(tgt_addr8, RSXX_HW_BLK_SIZE);
112	return tgt_addr8;
113}
114
115unsigned int rsxx_get_dma_tgt(struct rsxx_cardinfo *card, u64 addr8)
116{
117	unsigned int tgt;
118
119	tgt = (addr8 >> card->_stripe.target_shift) & card->_stripe.target_mask;
120
121	return tgt;
122}
123
124static void rsxx_dma_queue_reset(struct rsxx_cardinfo *card)
125{
126	/* Reset all DMA Command/Status Queues */
127	iowrite32(DMA_QUEUE_RESET, card->regmap + RESET);
128}
129
130static unsigned int get_dma_size(struct rsxx_dma *dma)
131{
132	if (dma->sub_page.cnt)
133		return dma->sub_page.cnt << 9;
134	else
135		return RSXX_HW_BLK_SIZE;
136}
137
138
139/*----------------- DMA Tracker -------------------*/
140static void set_tracker_dma(struct dma_tracker_list *trackers,
141			    int tag,
142			    struct rsxx_dma *dma)
143{
144	trackers->list[tag].dma = dma;
145}
146
147static struct rsxx_dma *get_tracker_dma(struct dma_tracker_list *trackers,
148					    int tag)
149{
150	return trackers->list[tag].dma;
151}
152
153static int pop_tracker(struct dma_tracker_list *trackers)
154{
155	int tag;
156
157	spin_lock(&trackers->lock);
158	tag = trackers->head;
159	if (tag != -1) {
160		trackers->head = trackers->list[tag].next_tag;
161		trackers->list[tag].next_tag = -1;
162	}
163	spin_unlock(&trackers->lock);
164
165	return tag;
166}
167
168static void push_tracker(struct dma_tracker_list *trackers, int tag)
169{
170	spin_lock(&trackers->lock);
171	trackers->list[tag].next_tag = trackers->head;
172	trackers->head = tag;
173	trackers->list[tag].dma = NULL;
174	spin_unlock(&trackers->lock);
175}
176
177
178/*----------------- Interrupt Coalescing -------------*/
179/*
180 * Interrupt Coalescing Register Format:
181 * Interrupt Timer (64ns units) [15:0]
182 * Interrupt Count [24:16]
183 * Reserved [31:25]
184*/
185#define INTR_COAL_LATENCY_MASK       (0x0000ffff)
186
187#define INTR_COAL_COUNT_SHIFT        16
188#define INTR_COAL_COUNT_BITS         9
189#define INTR_COAL_COUNT_MASK         (((1 << INTR_COAL_COUNT_BITS) - 1) << \
190					INTR_COAL_COUNT_SHIFT)
191#define INTR_COAL_LATENCY_UNITS_NS   64
192
193
194static u32 dma_intr_coal_val(u32 mode, u32 count, u32 latency)
195{
196	u32 latency_units = latency / INTR_COAL_LATENCY_UNITS_NS;
197
198	if (mode == RSXX_INTR_COAL_DISABLED)
199		return 0;
200
201	return ((count << INTR_COAL_COUNT_SHIFT) & INTR_COAL_COUNT_MASK) |
202			(latency_units & INTR_COAL_LATENCY_MASK);
203
204}
205
206static void dma_intr_coal_auto_tune(struct rsxx_cardinfo *card)
207{
208	int i;
209	u32 q_depth = 0;
210	u32 intr_coal;
211
212	if (card->config.data.intr_coal.mode != RSXX_INTR_COAL_AUTO_TUNE)
213		return;
214
215	for (i = 0; i < card->n_targets; i++)
216		q_depth += atomic_read(&card->ctrl[i].stats.hw_q_depth);
217
218	intr_coal = dma_intr_coal_val(card->config.data.intr_coal.mode,
219				      q_depth / 2,
220				      card->config.data.intr_coal.latency);
221	iowrite32(intr_coal, card->regmap + INTR_COAL);
222}
223
224/*----------------- RSXX DMA Handling -------------------*/
225static void rsxx_complete_dma(struct rsxx_cardinfo *card,
226				  struct rsxx_dma *dma,
227				  unsigned int status)
228{
229	if (status & DMA_SW_ERR)
230		printk_ratelimited(KERN_ERR
231				   "SW Error in DMA(cmd x%02x, laddr x%08x)\n",
232				   dma->cmd, dma->laddr);
233	if (status & DMA_HW_FAULT)
234		printk_ratelimited(KERN_ERR
235				   "HW Fault in DMA(cmd x%02x, laddr x%08x)\n",
236				   dma->cmd, dma->laddr);
237	if (status & DMA_CANCELLED)
238		printk_ratelimited(KERN_ERR
239				   "DMA Cancelled(cmd x%02x, laddr x%08x)\n",
240				   dma->cmd, dma->laddr);
241
242	if (dma->dma_addr)
243		pci_unmap_page(card->dev, dma->dma_addr, get_dma_size(dma),
244			       dma->cmd == HW_CMD_BLK_WRITE ?
245					   PCI_DMA_TODEVICE :
246					   PCI_DMA_FROMDEVICE);
247
248	if (dma->cb)
249		dma->cb(card, dma->cb_data, status ? 1 : 0);
250
251	kmem_cache_free(rsxx_dma_pool, dma);
252}
253
254static void rsxx_requeue_dma(struct rsxx_dma_ctrl *ctrl,
255				 struct rsxx_dma *dma)
256{
257	/*
258	 * Requeued DMAs go to the front of the queue so they are issued
259	 * first.
260	 */
261	spin_lock(&ctrl->queue_lock);
262	list_add(&dma->list, &ctrl->queue);
263	spin_unlock(&ctrl->queue_lock);
264}
265
266static void rsxx_handle_dma_error(struct rsxx_dma_ctrl *ctrl,
267				      struct rsxx_dma *dma,
268				      u8 hw_st)
269{
270	unsigned int status = 0;
271	int requeue_cmd = 0;
272
273	dev_dbg(CARD_TO_DEV(ctrl->card),
274		"Handling DMA error(cmd x%02x, laddr x%08x st:x%02x)\n",
275		dma->cmd, dma->laddr, hw_st);
276
277	if (hw_st & HW_STATUS_CRC)
278		ctrl->stats.crc_errors++;
279	if (hw_st & HW_STATUS_HARD_ERR)
280		ctrl->stats.hard_errors++;
281	if (hw_st & HW_STATUS_SOFT_ERR)
282		ctrl->stats.soft_errors++;
283
284	switch (dma->cmd) {
285	case HW_CMD_BLK_READ:
286		if (hw_st & (HW_STATUS_CRC | HW_STATUS_HARD_ERR)) {
287			if (ctrl->card->scrub_hard) {
288				dma->cmd = HW_CMD_BLK_RECON_READ;
289				requeue_cmd = 1;
290				ctrl->stats.reads_retried++;
291			} else {
292				status |= DMA_HW_FAULT;
293				ctrl->stats.reads_failed++;
294			}
295		} else if (hw_st & HW_STATUS_FAULT) {
296			status |= DMA_HW_FAULT;
297			ctrl->stats.reads_failed++;
298		}
299
300		break;
301	case HW_CMD_BLK_RECON_READ:
302		if (hw_st & (HW_STATUS_CRC | HW_STATUS_HARD_ERR)) {
303			/* Data could not be reconstructed. */
304			status |= DMA_HW_FAULT;
305			ctrl->stats.reads_failed++;
306		}
307
308		break;
309	case HW_CMD_BLK_WRITE:
310		status |= DMA_HW_FAULT;
311		ctrl->stats.writes_failed++;
312
313		break;
314	case HW_CMD_BLK_DISCARD:
315		status |= DMA_HW_FAULT;
316		ctrl->stats.discards_failed++;
317
318		break;
319	default:
320		dev_err(CARD_TO_DEV(ctrl->card),
321			"Unknown command in DMA!(cmd: x%02x "
322			   "laddr x%08x st: x%02x\n",
323			   dma->cmd, dma->laddr, hw_st);
324		status |= DMA_SW_ERR;
325
326		break;
327	}
328
329	if (requeue_cmd)
330		rsxx_requeue_dma(ctrl, dma);
331	else
332		rsxx_complete_dma(ctrl->card, dma, status);
333}
334
335static void dma_engine_stalled(unsigned long data)
336{
337	struct rsxx_dma_ctrl *ctrl = (struct rsxx_dma_ctrl *)data;
338
339	if (atomic_read(&ctrl->stats.hw_q_depth) == 0)
340		return;
341
342	if (ctrl->cmd.idx != ioread32(ctrl->regmap + SW_CMD_IDX)) {
343		/*
344		 * The dma engine was stalled because the SW_CMD_IDX write
345		 * was lost. Issue it again to recover.
346		 */
347		dev_warn(CARD_TO_DEV(ctrl->card),
348			"SW_CMD_IDX write was lost, re-writing...\n");
349		iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
350		mod_timer(&ctrl->activity_timer,
351			  jiffies + DMA_ACTIVITY_TIMEOUT);
352	} else {
353		dev_warn(CARD_TO_DEV(ctrl->card),
354			"DMA channel %d has stalled, faulting interface.\n",
355			ctrl->id);
356		ctrl->card->dma_fault = 1;
357	}
358}
359
360static void rsxx_issue_dmas(struct work_struct *work)
361{
362	struct rsxx_dma_ctrl *ctrl;
363	struct rsxx_dma *dma;
364	int tag;
365	int cmds_pending = 0;
366	struct hw_cmd *hw_cmd_buf;
367
368	ctrl = container_of(work, struct rsxx_dma_ctrl, issue_dma_work);
369	hw_cmd_buf = ctrl->cmd.buf;
370
371	if (unlikely(ctrl->card->halt))
372		return;
373
374	while (1) {
375		spin_lock(&ctrl->queue_lock);
376		if (list_empty(&ctrl->queue)) {
377			spin_unlock(&ctrl->queue_lock);
378			break;
379		}
380		spin_unlock(&ctrl->queue_lock);
381
382		tag = pop_tracker(ctrl->trackers);
383		if (tag == -1)
384			break;
385
386		spin_lock(&ctrl->queue_lock);
387		dma = list_entry(ctrl->queue.next, struct rsxx_dma, list);
388		list_del(&dma->list);
389		ctrl->stats.sw_q_depth--;
390		spin_unlock(&ctrl->queue_lock);
391
392		/*
393		 * This will catch any DMAs that slipped in right before the
394		 * fault, but was queued after all the other DMAs were
395		 * cancelled.
396		 */
397		if (unlikely(ctrl->card->dma_fault)) {
398			push_tracker(ctrl->trackers, tag);
399			rsxx_complete_dma(ctrl->card, dma, DMA_CANCELLED);
400			continue;
401		}
402
403		set_tracker_dma(ctrl->trackers, tag, dma);
404		hw_cmd_buf[ctrl->cmd.idx].command  = dma->cmd;
405		hw_cmd_buf[ctrl->cmd.idx].tag      = tag;
406		hw_cmd_buf[ctrl->cmd.idx]._rsvd    = 0;
407		hw_cmd_buf[ctrl->cmd.idx].sub_page =
408					((dma->sub_page.cnt & 0x7) << 4) |
409					 (dma->sub_page.off & 0x7);
410
411		hw_cmd_buf[ctrl->cmd.idx].device_addr =
412					cpu_to_le32(dma->laddr);
413
414		hw_cmd_buf[ctrl->cmd.idx].host_addr =
415					cpu_to_le64(dma->dma_addr);
416
417		dev_dbg(CARD_TO_DEV(ctrl->card),
418			"Issue DMA%d(laddr %d tag %d) to idx %d\n",
419			ctrl->id, dma->laddr, tag, ctrl->cmd.idx);
420
421		ctrl->cmd.idx = (ctrl->cmd.idx + 1) & RSXX_CS_IDX_MASK;
422		cmds_pending++;
423
424		if (dma->cmd == HW_CMD_BLK_WRITE)
425			ctrl->stats.writes_issued++;
426		else if (dma->cmd == HW_CMD_BLK_DISCARD)
427			ctrl->stats.discards_issued++;
428		else
429			ctrl->stats.reads_issued++;
430	}
431
432	/* Let HW know we've queued commands. */
433	if (cmds_pending) {
434		/*
435		 * We must guarantee that the CPU writes to 'ctrl->cmd.buf'
436		 * (which is in PCI-consistent system-memory) from the loop
437		 * above make it into the coherency domain before the
438		 * following PIO "trigger" updating the cmd.idx.  A WMB is
439		 * sufficient. We need not explicitly CPU cache-flush since
440		 * the memory is a PCI-consistent (ie; coherent) mapping.
441		 */
442		wmb();
443
444		atomic_add(cmds_pending, &ctrl->stats.hw_q_depth);
445		mod_timer(&ctrl->activity_timer,
446			  jiffies + DMA_ACTIVITY_TIMEOUT);
447		iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
448	}
449}
450
451static void rsxx_dma_done(struct work_struct *work)
452{
453	struct rsxx_dma_ctrl *ctrl;
454	struct rsxx_dma *dma;
455	unsigned long flags;
456	u16 count;
457	u8 status;
458	u8 tag;
459	struct hw_status *hw_st_buf;
460
461	ctrl = container_of(work, struct rsxx_dma_ctrl, dma_done_work);
462	hw_st_buf = ctrl->status.buf;
463
464	if (unlikely(ctrl->card->halt) ||
465	    unlikely(ctrl->card->dma_fault))
466		return;
467
468	count = le16_to_cpu(hw_st_buf[ctrl->status.idx].count);
469
470	while (count == ctrl->e_cnt) {
471		/*
472		 * The read memory-barrier is necessary to keep aggressive
473		 * processors/optimizers (such as the PPC Apple G5) from
474		 * reordering the following status-buffer tag & status read
475		 * *before* the count read on subsequent iterations of the
476		 * loop!
477		 */
478		rmb();
479
480		status = hw_st_buf[ctrl->status.idx].status;
481		tag    = hw_st_buf[ctrl->status.idx].tag;
482
483		dma = get_tracker_dma(ctrl->trackers, tag);
484		if (dma == NULL) {
485			spin_lock_irqsave(&ctrl->card->irq_lock, flags);
486			rsxx_disable_ier(ctrl->card, CR_INTR_DMA_ALL);
487			spin_unlock_irqrestore(&ctrl->card->irq_lock, flags);
488
489			dev_err(CARD_TO_DEV(ctrl->card),
490				"No tracker for tag %d "
491				"(idx %d id %d)\n",
492				tag, ctrl->status.idx, ctrl->id);
493			return;
494		}
495
496		dev_dbg(CARD_TO_DEV(ctrl->card),
497			"Completing DMA%d"
498			"(laddr x%x tag %d st: x%x cnt: x%04x) from idx %d.\n",
499			ctrl->id, dma->laddr, tag, status, count,
500			ctrl->status.idx);
501
502		atomic_dec(&ctrl->stats.hw_q_depth);
503
504		mod_timer(&ctrl->activity_timer,
505			  jiffies + DMA_ACTIVITY_TIMEOUT);
506
507		if (status)
508			rsxx_handle_dma_error(ctrl, dma, status);
509		else
510			rsxx_complete_dma(ctrl->card, dma, 0);
511
512		push_tracker(ctrl->trackers, tag);
513
514		ctrl->status.idx = (ctrl->status.idx + 1) &
515				   RSXX_CS_IDX_MASK;
516		ctrl->e_cnt++;
517
518		count = le16_to_cpu(hw_st_buf[ctrl->status.idx].count);
519	}
520
521	dma_intr_coal_auto_tune(ctrl->card);
522
523	if (atomic_read(&ctrl->stats.hw_q_depth) == 0)
524		del_timer_sync(&ctrl->activity_timer);
525
526	spin_lock_irqsave(&ctrl->card->irq_lock, flags);
527	rsxx_enable_ier(ctrl->card, CR_INTR_DMA(ctrl->id));
528	spin_unlock_irqrestore(&ctrl->card->irq_lock, flags);
529
530	spin_lock(&ctrl->queue_lock);
531	if (ctrl->stats.sw_q_depth)
532		queue_work(ctrl->issue_wq, &ctrl->issue_dma_work);
533	spin_unlock(&ctrl->queue_lock);
534}
535
536static int rsxx_cleanup_dma_queue(struct rsxx_cardinfo *card,
537				      struct list_head *q)
538{
539	struct rsxx_dma *dma;
540	struct rsxx_dma *tmp;
541	int cnt = 0;
542
543	list_for_each_entry_safe(dma, tmp, q, list) {
544		list_del(&dma->list);
545
546		if (dma->dma_addr)
547			pci_unmap_page(card->dev, dma->dma_addr,
548				       get_dma_size(dma),
549				       (dma->cmd == HW_CMD_BLK_WRITE) ?
550				       PCI_DMA_TODEVICE :
551				       PCI_DMA_FROMDEVICE);
552		kmem_cache_free(rsxx_dma_pool, dma);
553		cnt++;
554	}
555
556	return cnt;
557}
558
559static int rsxx_queue_discard(struct rsxx_cardinfo *card,
560				  struct list_head *q,
561				  unsigned int laddr,
562				  rsxx_dma_cb cb,
563				  void *cb_data)
564{
565	struct rsxx_dma *dma;
566
567	dma = kmem_cache_alloc(rsxx_dma_pool, GFP_KERNEL);
568	if (!dma)
569		return -ENOMEM;
570
571	dma->cmd          = HW_CMD_BLK_DISCARD;
572	dma->laddr        = laddr;
573	dma->dma_addr     = 0;
574	dma->sub_page.off = 0;
575	dma->sub_page.cnt = 0;
576	dma->page         = NULL;
577	dma->pg_off       = 0;
578	dma->cb	          = cb;
579	dma->cb_data      = cb_data;
580
581	dev_dbg(CARD_TO_DEV(card), "Queuing[D] laddr %x\n", dma->laddr);
582
583	list_add_tail(&dma->list, q);
584
585	return 0;
586}
587
588static int rsxx_queue_dma(struct rsxx_cardinfo *card,
589			      struct list_head *q,
590			      int dir,
591			      unsigned int dma_off,
592			      unsigned int dma_len,
593			      unsigned int laddr,
594			      struct page *page,
595			      unsigned int pg_off,
596			      rsxx_dma_cb cb,
597			      void *cb_data)
598{
599	struct rsxx_dma *dma;
600
601	dma = kmem_cache_alloc(rsxx_dma_pool, GFP_KERNEL);
602	if (!dma)
603		return -ENOMEM;
604
605	dma->dma_addr = pci_map_page(card->dev, page, pg_off, dma_len,
606				     dir ? PCI_DMA_TODEVICE :
607				     PCI_DMA_FROMDEVICE);
608	if (!dma->dma_addr) {
609		kmem_cache_free(rsxx_dma_pool, dma);
610		return -ENOMEM;
611	}
612
613	dma->cmd          = dir ? HW_CMD_BLK_WRITE : HW_CMD_BLK_READ;
614	dma->laddr        = laddr;
615	dma->sub_page.off = (dma_off >> 9);
616	dma->sub_page.cnt = (dma_len >> 9);
617	dma->page         = page;
618	dma->pg_off       = pg_off;
619	dma->cb	          = cb;
620	dma->cb_data      = cb_data;
621
622	dev_dbg(CARD_TO_DEV(card),
623		"Queuing[%c] laddr %x off %d cnt %d page %p pg_off %d\n",
624		dir ? 'W' : 'R', dma->laddr, dma->sub_page.off,
625		dma->sub_page.cnt, dma->page, dma->pg_off);
626
627	/* Queue the DMA */
628	list_add_tail(&dma->list, q);
629
630	return 0;
631}
632
633int rsxx_dma_queue_bio(struct rsxx_cardinfo *card,
634			   struct bio *bio,
635			   atomic_t *n_dmas,
636			   rsxx_dma_cb cb,
637			   void *cb_data)
638{
639	struct list_head dma_list[RSXX_MAX_TARGETS];
640	struct bio_vec *bvec;
641	unsigned long long addr8;
642	unsigned int laddr;
643	unsigned int bv_len;
644	unsigned int bv_off;
645	unsigned int dma_off;
646	unsigned int dma_len;
647	int dma_cnt[RSXX_MAX_TARGETS];
648	int tgt;
649	int st;
650	int i;
651
652	addr8 = bio->bi_sector << 9; /* sectors are 512 bytes */
653	atomic_set(n_dmas, 0);
654
655	for (i = 0; i < card->n_targets; i++) {
656		INIT_LIST_HEAD(&dma_list[i]);
657		dma_cnt[i] = 0;
658	}
659
660	if (bio->bi_rw & REQ_DISCARD) {
661		bv_len = bio->bi_size;
662
663		while (bv_len > 0) {
664			tgt   = rsxx_get_dma_tgt(card, addr8);
665			laddr = rsxx_addr8_to_laddr(addr8, card);
666
667			st = rsxx_queue_discard(card, &dma_list[tgt], laddr,
668						    cb, cb_data);
669			if (st)
670				goto bvec_err;
671
672			dma_cnt[tgt]++;
673			atomic_inc(n_dmas);
674			addr8  += RSXX_HW_BLK_SIZE;
675			bv_len -= RSXX_HW_BLK_SIZE;
676		}
677	} else {
678		bio_for_each_segment(bvec, bio, i) {
679			bv_len = bvec->bv_len;
680			bv_off = bvec->bv_offset;
681
682			while (bv_len > 0) {
683				tgt   = rsxx_get_dma_tgt(card, addr8);
684				laddr = rsxx_addr8_to_laddr(addr8, card);
685				dma_off = addr8 & RSXX_HW_BLK_MASK;
686				dma_len = min(bv_len,
687					      RSXX_HW_BLK_SIZE - dma_off);
688
689				st = rsxx_queue_dma(card, &dma_list[tgt],
690							bio_data_dir(bio),
691							dma_off, dma_len,
692							laddr, bvec->bv_page,
693							bv_off, cb, cb_data);
694				if (st)
695					goto bvec_err;
696
697				dma_cnt[tgt]++;
698				atomic_inc(n_dmas);
699				addr8  += dma_len;
700				bv_off += dma_len;
701				bv_len -= dma_len;
702			}
703		}
704	}
705
706	for (i = 0; i < card->n_targets; i++) {
707		if (!list_empty(&dma_list[i])) {
708			spin_lock(&card->ctrl[i].queue_lock);
709			card->ctrl[i].stats.sw_q_depth += dma_cnt[i];
710			list_splice_tail(&dma_list[i], &card->ctrl[i].queue);
711			spin_unlock(&card->ctrl[i].queue_lock);
712
713			queue_work(card->ctrl[i].issue_wq,
714				   &card->ctrl[i].issue_dma_work);
715		}
716	}
717
718	return 0;
719
720bvec_err:
721	for (i = 0; i < card->n_targets; i++)
722		rsxx_cleanup_dma_queue(card, &dma_list[i]);
723
724	return st;
725}
726
727
728/*----------------- DMA Engine Initialization & Setup -------------------*/
729static int rsxx_dma_ctrl_init(struct pci_dev *dev,
730				  struct rsxx_dma_ctrl *ctrl)
731{
732	int i;
733
734	memset(&ctrl->stats, 0, sizeof(ctrl->stats));
735
736	ctrl->status.buf = pci_alloc_consistent(dev, STATUS_BUFFER_SIZE8,
737						&ctrl->status.dma_addr);
738	ctrl->cmd.buf = pci_alloc_consistent(dev, COMMAND_BUFFER_SIZE8,
739					     &ctrl->cmd.dma_addr);
740	if (ctrl->status.buf == NULL || ctrl->cmd.buf == NULL)
741		return -ENOMEM;
742
743	ctrl->trackers = vmalloc(DMA_TRACKER_LIST_SIZE8);
744	if (!ctrl->trackers)
745		return -ENOMEM;
746
747	ctrl->trackers->head = 0;
748	for (i = 0; i < RSXX_MAX_OUTSTANDING_CMDS; i++) {
749		ctrl->trackers->list[i].next_tag = i + 1;
750		ctrl->trackers->list[i].dma = NULL;
751	}
752	ctrl->trackers->list[RSXX_MAX_OUTSTANDING_CMDS-1].next_tag = -1;
753	spin_lock_init(&ctrl->trackers->lock);
754
755	spin_lock_init(&ctrl->queue_lock);
756	INIT_LIST_HEAD(&ctrl->queue);
757
758	setup_timer(&ctrl->activity_timer, dma_engine_stalled,
759		    (unsigned long)ctrl);
760
761	ctrl->issue_wq = alloc_ordered_workqueue(DRIVER_NAME"_issue", 0);
762	if (!ctrl->issue_wq)
763		return -ENOMEM;
764
765	ctrl->done_wq = alloc_ordered_workqueue(DRIVER_NAME"_done", 0);
766	if (!ctrl->done_wq)
767		return -ENOMEM;
768
769	INIT_WORK(&ctrl->issue_dma_work, rsxx_issue_dmas);
770	INIT_WORK(&ctrl->dma_done_work, rsxx_dma_done);
771
772	memset(ctrl->status.buf, 0xac, STATUS_BUFFER_SIZE8);
773	iowrite32(lower_32_bits(ctrl->status.dma_addr),
774		  ctrl->regmap + SB_ADD_LO);
775	iowrite32(upper_32_bits(ctrl->status.dma_addr),
776		  ctrl->regmap + SB_ADD_HI);
777
778	memset(ctrl->cmd.buf, 0x83, COMMAND_BUFFER_SIZE8);
779	iowrite32(lower_32_bits(ctrl->cmd.dma_addr), ctrl->regmap + CB_ADD_LO);
780	iowrite32(upper_32_bits(ctrl->cmd.dma_addr), ctrl->regmap + CB_ADD_HI);
781
782	ctrl->status.idx = ioread32(ctrl->regmap + HW_STATUS_CNT);
783	if (ctrl->status.idx > RSXX_MAX_OUTSTANDING_CMDS) {
784		dev_crit(&dev->dev, "Failed reading status cnt x%x\n",
785			 ctrl->status.idx);
786		return -EINVAL;
787	}
788	iowrite32(ctrl->status.idx, ctrl->regmap + HW_STATUS_CNT);
789	iowrite32(ctrl->status.idx, ctrl->regmap + SW_STATUS_CNT);
790
791	ctrl->cmd.idx = ioread32(ctrl->regmap + HW_CMD_IDX);
792	if (ctrl->cmd.idx > RSXX_MAX_OUTSTANDING_CMDS) {
793		dev_crit(&dev->dev, "Failed reading cmd cnt x%x\n",
794			 ctrl->status.idx);
795		return -EINVAL;
796	}
797	iowrite32(ctrl->cmd.idx, ctrl->regmap + HW_CMD_IDX);
798	iowrite32(ctrl->cmd.idx, ctrl->regmap + SW_CMD_IDX);
799
800	wmb();
801
802	return 0;
803}
804
805int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
806			      unsigned int stripe_size8)
807{
808	if (!is_power_of_2(stripe_size8)) {
809		dev_err(CARD_TO_DEV(card),
810			"stripe_size is NOT a power of 2!\n");
811		return -EINVAL;
812	}
813
814	card->_stripe.lower_mask = stripe_size8 - 1;
815
816	card->_stripe.upper_mask  = ~(card->_stripe.lower_mask);
817	card->_stripe.upper_shift = ffs(card->n_targets) - 1;
818
819	card->_stripe.target_mask = card->n_targets - 1;
820	card->_stripe.target_shift = ffs(stripe_size8) - 1;
821
822	dev_dbg(CARD_TO_DEV(card), "_stripe.lower_mask   = x%016llx\n",
823		card->_stripe.lower_mask);
824	dev_dbg(CARD_TO_DEV(card), "_stripe.upper_shift  = x%016llx\n",
825		card->_stripe.upper_shift);
826	dev_dbg(CARD_TO_DEV(card), "_stripe.upper_mask   = x%016llx\n",
827		card->_stripe.upper_mask);
828	dev_dbg(CARD_TO_DEV(card), "_stripe.target_mask  = x%016llx\n",
829		card->_stripe.target_mask);
830	dev_dbg(CARD_TO_DEV(card), "_stripe.target_shift = x%016llx\n",
831		card->_stripe.target_shift);
832
833	return 0;
834}
835
836int rsxx_dma_configure(struct rsxx_cardinfo *card)
837{
838	u32 intr_coal;
839
840	intr_coal = dma_intr_coal_val(card->config.data.intr_coal.mode,
841				      card->config.data.intr_coal.count,
842				      card->config.data.intr_coal.latency);
843	iowrite32(intr_coal, card->regmap + INTR_COAL);
844
845	return rsxx_dma_stripe_setup(card, card->config.data.stripe_size);
846}
847
848int rsxx_dma_setup(struct rsxx_cardinfo *card)
849{
850	unsigned long flags;
851	int st;
852	int i;
853
854	dev_info(CARD_TO_DEV(card),
855		"Initializing %d DMA targets\n",
856		card->n_targets);
857
858	/* Regmap is divided up into 4K chunks. One for each DMA channel */
859	for (i = 0; i < card->n_targets; i++)
860		card->ctrl[i].regmap = card->regmap + (i * 4096);
861
862	card->dma_fault = 0;
863
864	/* Reset the DMA queues */
865	rsxx_dma_queue_reset(card);
866
867	/************* Setup DMA Control *************/
868	for (i = 0; i < card->n_targets; i++) {
869		st = rsxx_dma_ctrl_init(card->dev, &card->ctrl[i]);
870		if (st)
871			goto failed_dma_setup;
872
873		card->ctrl[i].card = card;
874		card->ctrl[i].id = i;
875	}
876
877	card->scrub_hard = 1;
878
879	if (card->config_valid)
880		rsxx_dma_configure(card);
881
882	/* Enable the interrupts after all setup has completed. */
883	for (i = 0; i < card->n_targets; i++) {
884		spin_lock_irqsave(&card->irq_lock, flags);
885		rsxx_enable_ier_and_isr(card, CR_INTR_DMA(i));
886		spin_unlock_irqrestore(&card->irq_lock, flags);
887	}
888
889	return 0;
890
891failed_dma_setup:
892	for (i = 0; i < card->n_targets; i++) {
893		struct rsxx_dma_ctrl *ctrl = &card->ctrl[i];
894
895		if (ctrl->issue_wq) {
896			destroy_workqueue(ctrl->issue_wq);
897			ctrl->issue_wq = NULL;
898		}
899
900		if (ctrl->done_wq) {
901			destroy_workqueue(ctrl->done_wq);
902			ctrl->done_wq = NULL;
903		}
904
905		if (ctrl->trackers)
906			vfree(ctrl->trackers);
907
908		if (ctrl->status.buf)
909			pci_free_consistent(card->dev, STATUS_BUFFER_SIZE8,
910					    ctrl->status.buf,
911					    ctrl->status.dma_addr);
912		if (ctrl->cmd.buf)
913			pci_free_consistent(card->dev, COMMAND_BUFFER_SIZE8,
914					    ctrl->cmd.buf, ctrl->cmd.dma_addr);
915	}
916
917	return st;
918}
919
920
921void rsxx_dma_destroy(struct rsxx_cardinfo *card)
922{
923	struct rsxx_dma_ctrl *ctrl;
924	struct rsxx_dma *dma;
925	int i, j;
926	int cnt = 0;
927
928	for (i = 0; i < card->n_targets; i++) {
929		ctrl = &card->ctrl[i];
930
931		if (ctrl->issue_wq) {
932			destroy_workqueue(ctrl->issue_wq);
933			ctrl->issue_wq = NULL;
934		}
935
936		if (ctrl->done_wq) {
937			destroy_workqueue(ctrl->done_wq);
938			ctrl->done_wq = NULL;
939		}
940
941		if (timer_pending(&ctrl->activity_timer))
942			del_timer_sync(&ctrl->activity_timer);
943
944		/* Clean up the DMA queue */
945		spin_lock(&ctrl->queue_lock);
946		cnt = rsxx_cleanup_dma_queue(card, &ctrl->queue);
947		spin_unlock(&ctrl->queue_lock);
948
949		if (cnt)
950			dev_info(CARD_TO_DEV(card),
951				"Freed %d queued DMAs on channel %d\n",
952				cnt, i);
953
954		/* Clean up issued DMAs */
955		for (j = 0; j < RSXX_MAX_OUTSTANDING_CMDS; j++) {
956			dma = get_tracker_dma(ctrl->trackers, j);
957			if (dma) {
958				pci_unmap_page(card->dev, dma->dma_addr,
959					       get_dma_size(dma),
960					       (dma->cmd == HW_CMD_BLK_WRITE) ?
961					       PCI_DMA_TODEVICE :
962					       PCI_DMA_FROMDEVICE);
963				kmem_cache_free(rsxx_dma_pool, dma);
964				cnt++;
965			}
966		}
967
968		if (cnt)
969			dev_info(CARD_TO_DEV(card),
970				"Freed %d pending DMAs on channel %d\n",
971				cnt, i);
972
973		vfree(ctrl->trackers);
974
975		pci_free_consistent(card->dev, STATUS_BUFFER_SIZE8,
976				    ctrl->status.buf, ctrl->status.dma_addr);
977		pci_free_consistent(card->dev, COMMAND_BUFFER_SIZE8,
978				    ctrl->cmd.buf, ctrl->cmd.dma_addr);
979	}
980}
981
982
983int rsxx_dma_init(void)
984{
985	rsxx_dma_pool = KMEM_CACHE(rsxx_dma, SLAB_HWCACHE_ALIGN);
986	if (!rsxx_dma_pool)
987		return -ENOMEM;
988
989	return 0;
990}
991
992
993void rsxx_dma_cleanup(void)
994{
995	kmem_cache_destroy(rsxx_dma_pool);
996}
997
998