1/*
2 * Copyright (c) 2007, 2008 QLogic Corporation. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <linux/spinlock.h>
34#include <linux/gfp.h>
35
36#include "ipath_kernel.h"
37#include "ipath_verbs.h"
38#include "ipath_common.h"
39
40#define SDMA_DESCQ_SZ PAGE_SIZE /* 256 entries per 4KB page */
41
42static void vl15_watchdog_enq(struct ipath_devdata *dd)
43{
44	/* ipath_sdma_lock must already be held */
45	if (atomic_inc_return(&dd->ipath_sdma_vl15_count) == 1) {
46		unsigned long interval = (HZ + 19) / 20;
47		dd->ipath_sdma_vl15_timer.expires = jiffies + interval;
48		add_timer(&dd->ipath_sdma_vl15_timer);
49	}
50}
51
52static void vl15_watchdog_deq(struct ipath_devdata *dd)
53{
54	/* ipath_sdma_lock must already be held */
55	if (atomic_dec_return(&dd->ipath_sdma_vl15_count) != 0) {
56		unsigned long interval = (HZ + 19) / 20;
57		mod_timer(&dd->ipath_sdma_vl15_timer, jiffies + interval);
58	} else {
59		del_timer(&dd->ipath_sdma_vl15_timer);
60	}
61}
62
63static void vl15_watchdog_timeout(unsigned long opaque)
64{
65	struct ipath_devdata *dd = (struct ipath_devdata *)opaque;
66
67	if (atomic_read(&dd->ipath_sdma_vl15_count) != 0) {
68		ipath_dbg("vl15 watchdog timeout - clearing\n");
69		ipath_cancel_sends(dd, 1);
70		ipath_hol_down(dd);
71	} else {
72		ipath_dbg("vl15 watchdog timeout - "
73			  "condition already cleared\n");
74	}
75}
76
77static void unmap_desc(struct ipath_devdata *dd, unsigned head)
78{
79	__le64 *descqp = &dd->ipath_sdma_descq[head].qw[0];
80	u64 desc[2];
81	dma_addr_t addr;
82	size_t len;
83
84	desc[0] = le64_to_cpu(descqp[0]);
85	desc[1] = le64_to_cpu(descqp[1]);
86
87	addr = (desc[1] << 32) | (desc[0] >> 32);
88	len = (desc[0] >> 14) & (0x7ffULL << 2);
89	dma_unmap_single(&dd->pcidev->dev, addr, len, DMA_TO_DEVICE);
90}
91
92/*
93 * ipath_sdma_lock should be locked before calling this.
94 */
95int ipath_sdma_make_progress(struct ipath_devdata *dd)
96{
97	struct list_head *lp = NULL;
98	struct ipath_sdma_txreq *txp = NULL;
99	u16 dmahead;
100	u16 start_idx = 0;
101	int progress = 0;
102
103	if (!list_empty(&dd->ipath_sdma_activelist)) {
104		lp = dd->ipath_sdma_activelist.next;
105		txp = list_entry(lp, struct ipath_sdma_txreq, list);
106		start_idx = txp->start_idx;
107	}
108
109	/*
110	 * Read the SDMA head register in order to know that the
111	 * interrupt clear has been written to the chip.
112	 * Otherwise, we may not get an interrupt for the last
113	 * descriptor in the queue.
114	 */
115	dmahead = (u16)ipath_read_kreg32(dd, dd->ipath_kregs->kr_senddmahead);
116	/* sanity check return value for error handling (chip reset, etc.) */
117	if (dmahead >= dd->ipath_sdma_descq_cnt)
118		goto done;
119
120	while (dd->ipath_sdma_descq_head != dmahead) {
121		if (txp && txp->flags & IPATH_SDMA_TXREQ_F_FREEDESC &&
122		    dd->ipath_sdma_descq_head == start_idx) {
123			unmap_desc(dd, dd->ipath_sdma_descq_head);
124			start_idx++;
125			if (start_idx == dd->ipath_sdma_descq_cnt)
126				start_idx = 0;
127		}
128
129		/* increment free count and head */
130		dd->ipath_sdma_descq_removed++;
131		if (++dd->ipath_sdma_descq_head == dd->ipath_sdma_descq_cnt)
132			dd->ipath_sdma_descq_head = 0;
133
134		if (txp && txp->next_descq_idx == dd->ipath_sdma_descq_head) {
135			/* move to notify list */
136			if (txp->flags & IPATH_SDMA_TXREQ_F_VL15)
137				vl15_watchdog_deq(dd);
138			list_move_tail(lp, &dd->ipath_sdma_notifylist);
139			if (!list_empty(&dd->ipath_sdma_activelist)) {
140				lp = dd->ipath_sdma_activelist.next;
141				txp = list_entry(lp, struct ipath_sdma_txreq,
142						 list);
143				start_idx = txp->start_idx;
144			} else {
145				lp = NULL;
146				txp = NULL;
147			}
148		}
149		progress = 1;
150	}
151
152	if (progress)
153		tasklet_hi_schedule(&dd->ipath_sdma_notify_task);
154
155done:
156	return progress;
157}
158
159static void ipath_sdma_notify(struct ipath_devdata *dd, struct list_head *list)
160{
161	struct ipath_sdma_txreq *txp, *txp_next;
162
163	list_for_each_entry_safe(txp, txp_next, list, list) {
164		list_del_init(&txp->list);
165
166		if (txp->callback)
167			(*txp->callback)(txp->callback_cookie,
168					 txp->callback_status);
169	}
170}
171
172static void sdma_notify_taskbody(struct ipath_devdata *dd)
173{
174	unsigned long flags;
175	struct list_head list;
176
177	INIT_LIST_HEAD(&list);
178
179	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
180
181	list_splice_init(&dd->ipath_sdma_notifylist, &list);
182
183	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
184
185	ipath_sdma_notify(dd, &list);
186
187	/*
188	 * The IB verbs layer needs to see the callback before getting
189	 * the call to ipath_ib_piobufavail() because the callback
190	 * handles releasing resources the next send will need.
191	 * Otherwise, we could do these calls in
192	 * ipath_sdma_make_progress().
193	 */
194	ipath_ib_piobufavail(dd->verbs_dev);
195}
196
197static void sdma_notify_task(unsigned long opaque)
198{
199	struct ipath_devdata *dd = (struct ipath_devdata *)opaque;
200
201	if (!test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status))
202		sdma_notify_taskbody(dd);
203}
204
205static void dump_sdma_state(struct ipath_devdata *dd)
206{
207	unsigned long reg;
208
209	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmastatus);
210	ipath_cdbg(VERBOSE, "kr_senddmastatus: 0x%016lx\n", reg);
211
212	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_sendctrl);
213	ipath_cdbg(VERBOSE, "kr_sendctrl: 0x%016lx\n", reg);
214
215	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmabufmask0);
216	ipath_cdbg(VERBOSE, "kr_senddmabufmask0: 0x%016lx\n", reg);
217
218	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmabufmask1);
219	ipath_cdbg(VERBOSE, "kr_senddmabufmask1: 0x%016lx\n", reg);
220
221	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmabufmask2);
222	ipath_cdbg(VERBOSE, "kr_senddmabufmask2: 0x%016lx\n", reg);
223
224	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmatail);
225	ipath_cdbg(VERBOSE, "kr_senddmatail: 0x%016lx\n", reg);
226
227	reg = ipath_read_kreg64(dd, dd->ipath_kregs->kr_senddmahead);
228	ipath_cdbg(VERBOSE, "kr_senddmahead: 0x%016lx\n", reg);
229}
230
231static void sdma_abort_task(unsigned long opaque)
232{
233	struct ipath_devdata *dd = (struct ipath_devdata *) opaque;
234	u64 status;
235	unsigned long flags;
236
237	if (test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status))
238		return;
239
240	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
241
242	status = dd->ipath_sdma_status & IPATH_SDMA_ABORT_MASK;
243
244	/* nothing to do */
245	if (status == IPATH_SDMA_ABORT_NONE)
246		goto unlock;
247
248	/* ipath_sdma_abort() is done, waiting for interrupt */
249	if (status == IPATH_SDMA_ABORT_DISARMED) {
250		if (time_before(jiffies, dd->ipath_sdma_abort_intr_timeout))
251			goto resched_noprint;
252		/* give up, intr got lost somewhere */
253		ipath_dbg("give up waiting for SDMADISABLED intr\n");
254		__set_bit(IPATH_SDMA_DISABLED, &dd->ipath_sdma_status);
255		status = IPATH_SDMA_ABORT_ABORTED;
256	}
257
258	/* everything is stopped, time to clean up and restart */
259	if (status == IPATH_SDMA_ABORT_ABORTED) {
260		struct ipath_sdma_txreq *txp, *txpnext;
261		u64 hwstatus;
262		int notify = 0;
263
264		hwstatus = ipath_read_kreg64(dd,
265				dd->ipath_kregs->kr_senddmastatus);
266
267		if ((hwstatus & (IPATH_SDMA_STATUS_SCORE_BOARD_DRAIN_IN_PROG |
268				 IPATH_SDMA_STATUS_ABORT_IN_PROG	     |
269				 IPATH_SDMA_STATUS_INTERNAL_SDMA_ENABLE)) ||
270		    !(hwstatus & IPATH_SDMA_STATUS_SCB_EMPTY)) {
271			if (dd->ipath_sdma_reset_wait > 0) {
272				/* not done shutting down sdma */
273				--dd->ipath_sdma_reset_wait;
274				goto resched;
275			}
276			ipath_cdbg(VERBOSE, "gave up waiting for quiescent "
277				"status after SDMA reset, continuing\n");
278			dump_sdma_state(dd);
279		}
280
281		/* dequeue all "sent" requests */
282		list_for_each_entry_safe(txp, txpnext,
283					 &dd->ipath_sdma_activelist, list) {
284			txp->callback_status = IPATH_SDMA_TXREQ_S_ABORTED;
285			if (txp->flags & IPATH_SDMA_TXREQ_F_VL15)
286				vl15_watchdog_deq(dd);
287			list_move_tail(&txp->list, &dd->ipath_sdma_notifylist);
288			notify = 1;
289		}
290		if (notify)
291			tasklet_hi_schedule(&dd->ipath_sdma_notify_task);
292
293		/* reset our notion of head and tail */
294		dd->ipath_sdma_descq_tail = 0;
295		dd->ipath_sdma_descq_head = 0;
296		dd->ipath_sdma_head_dma[0] = 0;
297		dd->ipath_sdma_generation = 0;
298		dd->ipath_sdma_descq_removed = dd->ipath_sdma_descq_added;
299
300		/* Reset SendDmaLenGen */
301		ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmalengen,
302			(u64) dd->ipath_sdma_descq_cnt | (1ULL << 18));
303
304		/* done with sdma state for a bit */
305		spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
306
307		/*
308		 * Don't restart sdma here (with the exception
309		 * below). Wait until link is up to ACTIVE.  VL15 MADs
310		 * used to bring the link up use PIO, and multiple link
311		 * transitions otherwise cause the sdma engine to be
312		 * stopped and started multiple times.
313		 * The disable is done here, including the shadow,
314		 * so the state is kept consistent.
315		 * See ipath_restart_sdma() for the actual starting
316		 * of sdma.
317		 */
318		spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
319		dd->ipath_sendctrl &= ~INFINIPATH_S_SDMAENABLE;
320		ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
321				 dd->ipath_sendctrl);
322		ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
323		spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
324
325		/* make sure I see next message */
326		dd->ipath_sdma_abort_jiffies = 0;
327
328		/*
329		 * Not everything that takes SDMA offline is a link
330		 * status change.  If the link was up, restart SDMA.
331		 */
332		if (dd->ipath_flags & IPATH_LINKACTIVE)
333			ipath_restart_sdma(dd);
334
335		goto done;
336	}
337
338resched:
339	/*
340	 * for now, keep spinning
341	 * JAG - this is bad to just have default be a loop without
342	 * state change
343	 */
344	if (time_after(jiffies, dd->ipath_sdma_abort_jiffies)) {
345		ipath_dbg("looping with status 0x%08lx\n",
346			  dd->ipath_sdma_status);
347		dd->ipath_sdma_abort_jiffies = jiffies + 5 * HZ;
348	}
349resched_noprint:
350	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
351	if (!test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status))
352		tasklet_hi_schedule(&dd->ipath_sdma_abort_task);
353	return;
354
355unlock:
356	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
357done:
358	return;
359}
360
361/*
362 * This is called from interrupt context.
363 */
364void ipath_sdma_intr(struct ipath_devdata *dd)
365{
366	unsigned long flags;
367
368	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
369
370	(void) ipath_sdma_make_progress(dd);
371
372	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
373}
374
375static int alloc_sdma(struct ipath_devdata *dd)
376{
377	int ret = 0;
378
379	/* Allocate memory for SendDMA descriptor FIFO */
380	dd->ipath_sdma_descq = dma_alloc_coherent(&dd->pcidev->dev,
381		SDMA_DESCQ_SZ, &dd->ipath_sdma_descq_phys, GFP_KERNEL);
382
383	if (!dd->ipath_sdma_descq) {
384		ipath_dev_err(dd, "failed to allocate SendDMA descriptor "
385			"FIFO memory\n");
386		ret = -ENOMEM;
387		goto done;
388	}
389
390	dd->ipath_sdma_descq_cnt =
391		SDMA_DESCQ_SZ / sizeof(struct ipath_sdma_desc);
392
393	/* Allocate memory for DMA of head register to memory */
394	dd->ipath_sdma_head_dma = dma_alloc_coherent(&dd->pcidev->dev,
395		PAGE_SIZE, &dd->ipath_sdma_head_phys, GFP_KERNEL);
396	if (!dd->ipath_sdma_head_dma) {
397		ipath_dev_err(dd, "failed to allocate SendDMA head memory\n");
398		ret = -ENOMEM;
399		goto cleanup_descq;
400	}
401	dd->ipath_sdma_head_dma[0] = 0;
402
403	init_timer(&dd->ipath_sdma_vl15_timer);
404	dd->ipath_sdma_vl15_timer.function = vl15_watchdog_timeout;
405	dd->ipath_sdma_vl15_timer.data = (unsigned long)dd;
406	atomic_set(&dd->ipath_sdma_vl15_count, 0);
407
408	goto done;
409
410cleanup_descq:
411	dma_free_coherent(&dd->pcidev->dev, SDMA_DESCQ_SZ,
412		(void *)dd->ipath_sdma_descq, dd->ipath_sdma_descq_phys);
413	dd->ipath_sdma_descq = NULL;
414	dd->ipath_sdma_descq_phys = 0;
415done:
416	return ret;
417}
418
419int setup_sdma(struct ipath_devdata *dd)
420{
421	int ret = 0;
422	unsigned i, n;
423	u64 tmp64;
424	u64 senddmabufmask[3] = { 0 };
425	unsigned long flags;
426
427	ret = alloc_sdma(dd);
428	if (ret)
429		goto done;
430
431	if (!dd->ipath_sdma_descq) {
432		ipath_dev_err(dd, "SendDMA memory not allocated\n");
433		goto done;
434	}
435
436	/*
437	 * Set initial status as if we had been up, then gone down.
438	 * This lets initial start on transition to ACTIVE be the
439	 * same as restart after link flap.
440	 */
441	dd->ipath_sdma_status = IPATH_SDMA_ABORT_ABORTED;
442	dd->ipath_sdma_abort_jiffies = 0;
443	dd->ipath_sdma_generation = 0;
444	dd->ipath_sdma_descq_tail = 0;
445	dd->ipath_sdma_descq_head = 0;
446	dd->ipath_sdma_descq_removed = 0;
447	dd->ipath_sdma_descq_added = 0;
448
449	/* Set SendDmaBase */
450	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabase,
451			 dd->ipath_sdma_descq_phys);
452	/* Set SendDmaLenGen */
453	tmp64 = dd->ipath_sdma_descq_cnt;
454	tmp64 |= 1<<18; /* enable generation checking */
455	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmalengen, tmp64);
456	/* Set SendDmaTail */
457	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmatail,
458			 dd->ipath_sdma_descq_tail);
459	/* Set SendDmaHeadAddr */
460	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmaheadaddr,
461			 dd->ipath_sdma_head_phys);
462
463	/*
464	 * Reserve all the former "kernel" piobufs, using high number range
465	 * so we get as many 4K buffers as possible
466	 */
467	n = dd->ipath_piobcnt2k + dd->ipath_piobcnt4k;
468	i = dd->ipath_lastport_piobuf + dd->ipath_pioreserved;
469	ipath_chg_pioavailkernel(dd, i, n - i , 0);
470	for (; i < n; ++i) {
471		unsigned word = i / 64;
472		unsigned bit = i & 63;
473		BUG_ON(word >= 3);
474		senddmabufmask[word] |= 1ULL << bit;
475	}
476	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask0,
477			 senddmabufmask[0]);
478	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask1,
479			 senddmabufmask[1]);
480	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask2,
481			 senddmabufmask[2]);
482
483	INIT_LIST_HEAD(&dd->ipath_sdma_activelist);
484	INIT_LIST_HEAD(&dd->ipath_sdma_notifylist);
485
486	tasklet_init(&dd->ipath_sdma_notify_task, sdma_notify_task,
487		     (unsigned long) dd);
488	tasklet_init(&dd->ipath_sdma_abort_task, sdma_abort_task,
489		     (unsigned long) dd);
490
491	/*
492	 * No use to turn on SDMA here, as link is probably not ACTIVE
493	 * Just mark it RUNNING and enable the interrupt, and let the
494	 * ipath_restart_sdma() on link transition to ACTIVE actually
495	 * enable it.
496	 */
497	spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
498	dd->ipath_sendctrl |= INFINIPATH_S_SDMAINTENABLE;
499	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
500	ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
501	__set_bit(IPATH_SDMA_RUNNING, &dd->ipath_sdma_status);
502	spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
503
504done:
505	return ret;
506}
507
508void teardown_sdma(struct ipath_devdata *dd)
509{
510	struct ipath_sdma_txreq *txp, *txpnext;
511	unsigned long flags;
512	dma_addr_t sdma_head_phys = 0;
513	dma_addr_t sdma_descq_phys = 0;
514	void *sdma_descq = NULL;
515	void *sdma_head_dma = NULL;
516
517	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
518	__clear_bit(IPATH_SDMA_RUNNING, &dd->ipath_sdma_status);
519	__set_bit(IPATH_SDMA_ABORTING, &dd->ipath_sdma_status);
520	__set_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status);
521	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
522
523	tasklet_kill(&dd->ipath_sdma_abort_task);
524	tasklet_kill(&dd->ipath_sdma_notify_task);
525
526	/* turn off sdma */
527	spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
528	dd->ipath_sendctrl &= ~INFINIPATH_S_SDMAENABLE;
529	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
530		dd->ipath_sendctrl);
531	ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
532	spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
533
534	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
535	/* dequeue all "sent" requests */
536	list_for_each_entry_safe(txp, txpnext, &dd->ipath_sdma_activelist,
537				 list) {
538		txp->callback_status = IPATH_SDMA_TXREQ_S_SHUTDOWN;
539		if (txp->flags & IPATH_SDMA_TXREQ_F_VL15)
540			vl15_watchdog_deq(dd);
541		list_move_tail(&txp->list, &dd->ipath_sdma_notifylist);
542	}
543	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
544
545	sdma_notify_taskbody(dd);
546
547	del_timer_sync(&dd->ipath_sdma_vl15_timer);
548
549	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
550
551	dd->ipath_sdma_abort_jiffies = 0;
552
553	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabase, 0);
554	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmalengen, 0);
555	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmatail, 0);
556	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmaheadaddr, 0);
557	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask0, 0);
558	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask1, 0);
559	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmabufmask2, 0);
560
561	if (dd->ipath_sdma_head_dma) {
562		sdma_head_dma = (void *) dd->ipath_sdma_head_dma;
563		sdma_head_phys = dd->ipath_sdma_head_phys;
564		dd->ipath_sdma_head_dma = NULL;
565		dd->ipath_sdma_head_phys = 0;
566	}
567
568	if (dd->ipath_sdma_descq) {
569		sdma_descq = dd->ipath_sdma_descq;
570		sdma_descq_phys = dd->ipath_sdma_descq_phys;
571		dd->ipath_sdma_descq = NULL;
572		dd->ipath_sdma_descq_phys = 0;
573	}
574
575	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
576
577	if (sdma_head_dma)
578		dma_free_coherent(&dd->pcidev->dev, PAGE_SIZE,
579				  sdma_head_dma, sdma_head_phys);
580
581	if (sdma_descq)
582		dma_free_coherent(&dd->pcidev->dev, SDMA_DESCQ_SZ,
583				  sdma_descq, sdma_descq_phys);
584}
585
586/*
587 * [Re]start SDMA, if we use it, and it's not already OK.
588 * This is called on transition to link ACTIVE, either the first or
589 * subsequent times.
590 */
591void ipath_restart_sdma(struct ipath_devdata *dd)
592{
593	unsigned long flags;
594	int needed = 1;
595
596	if (!(dd->ipath_flags & IPATH_HAS_SEND_DMA))
597		goto bail;
598
599	/*
600	 * First, make sure we should, which is to say,
601	 * check that we are "RUNNING" (not in teardown)
602	 * and not "SHUTDOWN"
603	 */
604	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
605	if (!test_bit(IPATH_SDMA_RUNNING, &dd->ipath_sdma_status)
606		|| test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status))
607			needed = 0;
608	else {
609		__clear_bit(IPATH_SDMA_DISABLED, &dd->ipath_sdma_status);
610		__clear_bit(IPATH_SDMA_DISARMED, &dd->ipath_sdma_status);
611		__clear_bit(IPATH_SDMA_ABORTING, &dd->ipath_sdma_status);
612	}
613	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
614	if (!needed) {
615		ipath_dbg("invalid attempt to restart SDMA, status 0x%08lx\n",
616			dd->ipath_sdma_status);
617		goto bail;
618	}
619	spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
620	/*
621	 * First clear, just to be safe. Enable is only done
622	 * in chip on 0->1 transition
623	 */
624	dd->ipath_sendctrl &= ~INFINIPATH_S_SDMAENABLE;
625	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
626	ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
627	dd->ipath_sendctrl |= INFINIPATH_S_SDMAENABLE;
628	ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
629	ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
630	spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
631
632	/* notify upper layers */
633	ipath_ib_piobufavail(dd->verbs_dev);
634
635bail:
636	return;
637}
638
639static inline void make_sdma_desc(struct ipath_devdata *dd,
640	u64 *sdmadesc, u64 addr, u64 dwlen, u64 dwoffset)
641{
642	WARN_ON(addr & 3);
643	/* SDmaPhyAddr[47:32] */
644	sdmadesc[1] = addr >> 32;
645	/* SDmaPhyAddr[31:0] */
646	sdmadesc[0] = (addr & 0xfffffffcULL) << 32;
647	/* SDmaGeneration[1:0] */
648	sdmadesc[0] |= (dd->ipath_sdma_generation & 3ULL) << 30;
649	/* SDmaDwordCount[10:0] */
650	sdmadesc[0] |= (dwlen & 0x7ffULL) << 16;
651	/* SDmaBufOffset[12:2] */
652	sdmadesc[0] |= dwoffset & 0x7ffULL;
653}
654
655/*
656 * This function queues one IB packet onto the send DMA queue per call.
657 * The caller is responsible for checking:
658 * 1) The number of send DMA descriptor entries is less than the size of
659 *    the descriptor queue.
660 * 2) The IB SGE addresses and lengths are 32-bit aligned
661 *    (except possibly the last SGE's length)
662 * 3) The SGE addresses are suitable for passing to dma_map_single().
663 */
664int ipath_sdma_verbs_send(struct ipath_devdata *dd,
665	struct ipath_sge_state *ss, u32 dwords,
666	struct ipath_verbs_txreq *tx)
667{
668
669	unsigned long flags;
670	struct ipath_sge *sge;
671	int ret = 0;
672	u16 tail;
673	__le64 *descqp;
674	u64 sdmadesc[2];
675	u32 dwoffset;
676	dma_addr_t addr;
677
678	if ((tx->map_len + (dwords<<2)) > dd->ipath_ibmaxlen) {
679		ipath_dbg("packet size %X > ibmax %X, fail\n",
680			tx->map_len + (dwords<<2), dd->ipath_ibmaxlen);
681		ret = -EMSGSIZE;
682		goto fail;
683	}
684
685	spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
686
687retry:
688	if (unlikely(test_bit(IPATH_SDMA_ABORTING, &dd->ipath_sdma_status))) {
689		ret = -EBUSY;
690		goto unlock;
691	}
692
693	if (tx->txreq.sg_count > ipath_sdma_descq_freecnt(dd)) {
694		if (ipath_sdma_make_progress(dd))
695			goto retry;
696		ret = -ENOBUFS;
697		goto unlock;
698	}
699
700	addr = dma_map_single(&dd->pcidev->dev, tx->txreq.map_addr,
701			      tx->map_len, DMA_TO_DEVICE);
702	if (dma_mapping_error(&dd->pcidev->dev, addr))
703		goto ioerr;
704
705	dwoffset = tx->map_len >> 2;
706	make_sdma_desc(dd, sdmadesc, (u64) addr, dwoffset, 0);
707
708	/* SDmaFirstDesc */
709	sdmadesc[0] |= 1ULL << 12;
710	if (tx->txreq.flags & IPATH_SDMA_TXREQ_F_USELARGEBUF)
711		sdmadesc[0] |= 1ULL << 14;	/* SDmaUseLargeBuf */
712
713	/* write to the descq */
714	tail = dd->ipath_sdma_descq_tail;
715	descqp = &dd->ipath_sdma_descq[tail].qw[0];
716	*descqp++ = cpu_to_le64(sdmadesc[0]);
717	*descqp++ = cpu_to_le64(sdmadesc[1]);
718
719	if (tx->txreq.flags & IPATH_SDMA_TXREQ_F_FREEDESC)
720		tx->txreq.start_idx = tail;
721
722	/* increment the tail */
723	if (++tail == dd->ipath_sdma_descq_cnt) {
724		tail = 0;
725		descqp = &dd->ipath_sdma_descq[0].qw[0];
726		++dd->ipath_sdma_generation;
727	}
728
729	sge = &ss->sge;
730	while (dwords) {
731		u32 dw;
732		u32 len;
733
734		len = dwords << 2;
735		if (len > sge->length)
736			len = sge->length;
737		if (len > sge->sge_length)
738			len = sge->sge_length;
739		BUG_ON(len == 0);
740		dw = (len + 3) >> 2;
741		addr = dma_map_single(&dd->pcidev->dev, sge->vaddr, dw << 2,
742				      DMA_TO_DEVICE);
743		if (dma_mapping_error(&dd->pcidev->dev, addr))
744			goto unmap;
745		make_sdma_desc(dd, sdmadesc, (u64) addr, dw, dwoffset);
746		/* SDmaUseLargeBuf has to be set in every descriptor */
747		if (tx->txreq.flags & IPATH_SDMA_TXREQ_F_USELARGEBUF)
748			sdmadesc[0] |= 1ULL << 14;
749		/* write to the descq */
750		*descqp++ = cpu_to_le64(sdmadesc[0]);
751		*descqp++ = cpu_to_le64(sdmadesc[1]);
752
753		/* increment the tail */
754		if (++tail == dd->ipath_sdma_descq_cnt) {
755			tail = 0;
756			descqp = &dd->ipath_sdma_descq[0].qw[0];
757			++dd->ipath_sdma_generation;
758		}
759		sge->vaddr += len;
760		sge->length -= len;
761		sge->sge_length -= len;
762		if (sge->sge_length == 0) {
763			if (--ss->num_sge)
764				*sge = *ss->sg_list++;
765		} else if (sge->length == 0 && sge->mr != NULL) {
766			if (++sge->n >= IPATH_SEGSZ) {
767				if (++sge->m >= sge->mr->mapsz)
768					break;
769				sge->n = 0;
770			}
771			sge->vaddr =
772				sge->mr->map[sge->m]->segs[sge->n].vaddr;
773			sge->length =
774				sge->mr->map[sge->m]->segs[sge->n].length;
775		}
776
777		dwoffset += dw;
778		dwords -= dw;
779	}
780
781	if (!tail)
782		descqp = &dd->ipath_sdma_descq[dd->ipath_sdma_descq_cnt].qw[0];
783	descqp -= 2;
784	/* SDmaLastDesc */
785	descqp[0] |= cpu_to_le64(1ULL << 11);
786	if (tx->txreq.flags & IPATH_SDMA_TXREQ_F_INTREQ) {
787		/* SDmaIntReq */
788		descqp[0] |= cpu_to_le64(1ULL << 15);
789	}
790
791	/* Commit writes to memory and advance the tail on the chip */
792	wmb();
793	ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmatail, tail);
794
795	tx->txreq.next_descq_idx = tail;
796	tx->txreq.callback_status = IPATH_SDMA_TXREQ_S_OK;
797	dd->ipath_sdma_descq_tail = tail;
798	dd->ipath_sdma_descq_added += tx->txreq.sg_count;
799	list_add_tail(&tx->txreq.list, &dd->ipath_sdma_activelist);
800	if (tx->txreq.flags & IPATH_SDMA_TXREQ_F_VL15)
801		vl15_watchdog_enq(dd);
802	goto unlock;
803
804unmap:
805	while (tail != dd->ipath_sdma_descq_tail) {
806		if (!tail)
807			tail = dd->ipath_sdma_descq_cnt - 1;
808		else
809			tail--;
810		unmap_desc(dd, tail);
811	}
812ioerr:
813	ret = -EIO;
814unlock:
815	spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
816fail:
817	return ret;
818}
819