1/*
2 * Copyright(c) 2015 - 2018 Intel Corporation.
3 *
4 * This file is provided under a dual BSD/GPLv2 license.  When using or
5 * redistributing this file, you may do so under either license.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * BSD LICENSE
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 *
24 *  - Redistributions of source code must retain the above copyright
25 *    notice, this list of conditions and the following disclaimer.
26 *  - Redistributions in binary form must reproduce the above copyright
27 *    notice, this list of conditions and the following disclaimer in
28 *    the documentation and/or other materials provided with the
29 *    distribution.
30 *  - Neither the name of Intel Corporation nor the names of its
31 *    contributors may be used to endorse or promote products derived
32 *    from this software without specific prior written permission.
33 *
34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 *
46 */
47
48#include <linux/spinlock.h>
49#include <linux/seqlock.h>
50#include <linux/netdevice.h>
51#include <linux/moduleparam.h>
52#include <linux/bitops.h>
53#include <linux/timer.h>
54#include <linux/vmalloc.h>
55#include <linux/highmem.h>
56
57#include "hfi.h"
58#include "common.h"
59#include "qp.h"
60#include "sdma.h"
61#include "iowait.h"
62#include "trace.h"
63
64/* must be a power of 2 >= 64 <= 32768 */
65#define SDMA_DESCQ_CNT 2048
66#define SDMA_DESC_INTR 64
67#define INVALID_TAIL 0xffff
68#define SDMA_PAD max_t(size_t, MAX_16B_PADDING, sizeof(u32))
69
70static uint sdma_descq_cnt = SDMA_DESCQ_CNT;
71module_param(sdma_descq_cnt, uint, S_IRUGO);
72MODULE_PARM_DESC(sdma_descq_cnt, "Number of SDMA descq entries");
73
74static uint sdma_idle_cnt = 250;
75module_param(sdma_idle_cnt, uint, S_IRUGO);
76MODULE_PARM_DESC(sdma_idle_cnt, "sdma interrupt idle delay (ns,default 250)");
77
78uint mod_num_sdma;
79module_param_named(num_sdma, mod_num_sdma, uint, S_IRUGO);
80MODULE_PARM_DESC(num_sdma, "Set max number SDMA engines to use");
81
82static uint sdma_desct_intr = SDMA_DESC_INTR;
83module_param_named(desct_intr, sdma_desct_intr, uint, S_IRUGO | S_IWUSR);
84MODULE_PARM_DESC(desct_intr, "Number of SDMA descriptor before interrupt");
85
86#define SDMA_WAIT_BATCH_SIZE 20
87/* max wait time for a SDMA engine to indicate it has halted */
88#define SDMA_ERR_HALT_TIMEOUT 10 /* ms */
89/* all SDMA engine errors that cause a halt */
90
91#define SD(name) SEND_DMA_##name
92#define ALL_SDMA_ENG_HALT_ERRS \
93	(SD(ENG_ERR_STATUS_SDMA_WRONG_DW_ERR_SMASK) \
94	| SD(ENG_ERR_STATUS_SDMA_GEN_MISMATCH_ERR_SMASK) \
95	| SD(ENG_ERR_STATUS_SDMA_TOO_LONG_ERR_SMASK) \
96	| SD(ENG_ERR_STATUS_SDMA_TAIL_OUT_OF_BOUNDS_ERR_SMASK) \
97	| SD(ENG_ERR_STATUS_SDMA_FIRST_DESC_ERR_SMASK) \
98	| SD(ENG_ERR_STATUS_SDMA_MEM_READ_ERR_SMASK) \
99	| SD(ENG_ERR_STATUS_SDMA_HALT_ERR_SMASK) \
100	| SD(ENG_ERR_STATUS_SDMA_LENGTH_MISMATCH_ERR_SMASK) \
101	| SD(ENG_ERR_STATUS_SDMA_PACKET_DESC_OVERFLOW_ERR_SMASK) \
102	| SD(ENG_ERR_STATUS_SDMA_HEADER_SELECT_ERR_SMASK) \
103	| SD(ENG_ERR_STATUS_SDMA_HEADER_ADDRESS_ERR_SMASK) \
104	| SD(ENG_ERR_STATUS_SDMA_HEADER_LENGTH_ERR_SMASK) \
105	| SD(ENG_ERR_STATUS_SDMA_TIMEOUT_ERR_SMASK) \
106	| SD(ENG_ERR_STATUS_SDMA_DESC_TABLE_UNC_ERR_SMASK) \
107	| SD(ENG_ERR_STATUS_SDMA_ASSEMBLY_UNC_ERR_SMASK) \
108	| SD(ENG_ERR_STATUS_SDMA_PACKET_TRACKING_UNC_ERR_SMASK) \
109	| SD(ENG_ERR_STATUS_SDMA_HEADER_STORAGE_UNC_ERR_SMASK) \
110	| SD(ENG_ERR_STATUS_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_SMASK))
111
112/* sdma_sendctrl operations */
113#define SDMA_SENDCTRL_OP_ENABLE    BIT(0)
114#define SDMA_SENDCTRL_OP_INTENABLE BIT(1)
115#define SDMA_SENDCTRL_OP_HALT      BIT(2)
116#define SDMA_SENDCTRL_OP_CLEANUP   BIT(3)
117
118/* handle long defines */
119#define SDMA_EGRESS_PACKET_OCCUPANCY_SMASK \
120SEND_EGRESS_SEND_DMA_STATUS_SDMA_EGRESS_PACKET_OCCUPANCY_SMASK
121#define SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT \
122SEND_EGRESS_SEND_DMA_STATUS_SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT
123
124static const char * const sdma_state_names[] = {
125	[sdma_state_s00_hw_down]                = "s00_HwDown",
126	[sdma_state_s10_hw_start_up_halt_wait]  = "s10_HwStartUpHaltWait",
127	[sdma_state_s15_hw_start_up_clean_wait] = "s15_HwStartUpCleanWait",
128	[sdma_state_s20_idle]                   = "s20_Idle",
129	[sdma_state_s30_sw_clean_up_wait]       = "s30_SwCleanUpWait",
130	[sdma_state_s40_hw_clean_up_wait]       = "s40_HwCleanUpWait",
131	[sdma_state_s50_hw_halt_wait]           = "s50_HwHaltWait",
132	[sdma_state_s60_idle_halt_wait]         = "s60_IdleHaltWait",
133	[sdma_state_s80_hw_freeze]		= "s80_HwFreeze",
134	[sdma_state_s82_freeze_sw_clean]	= "s82_FreezeSwClean",
135	[sdma_state_s99_running]                = "s99_Running",
136};
137
138#ifdef CONFIG_SDMA_VERBOSITY
139static const char * const sdma_event_names[] = {
140	[sdma_event_e00_go_hw_down]   = "e00_GoHwDown",
141	[sdma_event_e10_go_hw_start]  = "e10_GoHwStart",
142	[sdma_event_e15_hw_halt_done] = "e15_HwHaltDone",
143	[sdma_event_e25_hw_clean_up_done] = "e25_HwCleanUpDone",
144	[sdma_event_e30_go_running]   = "e30_GoRunning",
145	[sdma_event_e40_sw_cleaned]   = "e40_SwCleaned",
146	[sdma_event_e50_hw_cleaned]   = "e50_HwCleaned",
147	[sdma_event_e60_hw_halted]    = "e60_HwHalted",
148	[sdma_event_e70_go_idle]      = "e70_GoIdle",
149	[sdma_event_e80_hw_freeze]    = "e80_HwFreeze",
150	[sdma_event_e81_hw_frozen]    = "e81_HwFrozen",
151	[sdma_event_e82_hw_unfreeze]  = "e82_HwUnfreeze",
152	[sdma_event_e85_link_down]    = "e85_LinkDown",
153	[sdma_event_e90_sw_halted]    = "e90_SwHalted",
154};
155#endif
156
157static const struct sdma_set_state_action sdma_action_table[] = {
158	[sdma_state_s00_hw_down] = {
159		.go_s99_running_tofalse = 1,
160		.op_enable = 0,
161		.op_intenable = 0,
162		.op_halt = 0,
163		.op_cleanup = 0,
164	},
165	[sdma_state_s10_hw_start_up_halt_wait] = {
166		.op_enable = 0,
167		.op_intenable = 0,
168		.op_halt = 1,
169		.op_cleanup = 0,
170	},
171	[sdma_state_s15_hw_start_up_clean_wait] = {
172		.op_enable = 0,
173		.op_intenable = 1,
174		.op_halt = 0,
175		.op_cleanup = 1,
176	},
177	[sdma_state_s20_idle] = {
178		.op_enable = 0,
179		.op_intenable = 1,
180		.op_halt = 0,
181		.op_cleanup = 0,
182	},
183	[sdma_state_s30_sw_clean_up_wait] = {
184		.op_enable = 0,
185		.op_intenable = 0,
186		.op_halt = 0,
187		.op_cleanup = 0,
188	},
189	[sdma_state_s40_hw_clean_up_wait] = {
190		.op_enable = 0,
191		.op_intenable = 0,
192		.op_halt = 0,
193		.op_cleanup = 1,
194	},
195	[sdma_state_s50_hw_halt_wait] = {
196		.op_enable = 0,
197		.op_intenable = 0,
198		.op_halt = 0,
199		.op_cleanup = 0,
200	},
201	[sdma_state_s60_idle_halt_wait] = {
202		.go_s99_running_tofalse = 1,
203		.op_enable = 0,
204		.op_intenable = 0,
205		.op_halt = 1,
206		.op_cleanup = 0,
207	},
208	[sdma_state_s80_hw_freeze] = {
209		.op_enable = 0,
210		.op_intenable = 0,
211		.op_halt = 0,
212		.op_cleanup = 0,
213	},
214	[sdma_state_s82_freeze_sw_clean] = {
215		.op_enable = 0,
216		.op_intenable = 0,
217		.op_halt = 0,
218		.op_cleanup = 0,
219	},
220	[sdma_state_s99_running] = {
221		.op_enable = 1,
222		.op_intenable = 1,
223		.op_halt = 0,
224		.op_cleanup = 0,
225		.go_s99_running_totrue = 1,
226	},
227};
228
229#define SDMA_TAIL_UPDATE_THRESH 0x1F
230
231/* declare all statics here rather than keep sorting */
232static void sdma_complete(struct kref *);
233static void sdma_finalput(struct sdma_state *);
234static void sdma_get(struct sdma_state *);
235static void sdma_hw_clean_up_task(struct tasklet_struct *);
236static void sdma_put(struct sdma_state *);
237static void sdma_set_state(struct sdma_engine *, enum sdma_states);
238static void sdma_start_hw_clean_up(struct sdma_engine *);
239static void sdma_sw_clean_up_task(struct tasklet_struct *);
240static void sdma_sendctrl(struct sdma_engine *, unsigned);
241static void init_sdma_regs(struct sdma_engine *, u32, uint);
242static void sdma_process_event(
243	struct sdma_engine *sde,
244	enum sdma_events event);
245static void __sdma_process_event(
246	struct sdma_engine *sde,
247	enum sdma_events event);
248static void dump_sdma_state(struct sdma_engine *sde);
249static void sdma_make_progress(struct sdma_engine *sde, u64 status);
250static void sdma_desc_avail(struct sdma_engine *sde, uint avail);
251static void sdma_flush_descq(struct sdma_engine *sde);
252
253/**
254 * sdma_state_name() - return state string from enum
255 * @state: state
256 */
257static const char *sdma_state_name(enum sdma_states state)
258{
259	return sdma_state_names[state];
260}
261
262static void sdma_get(struct sdma_state *ss)
263{
264	kref_get(&ss->kref);
265}
266
267static void sdma_complete(struct kref *kref)
268{
269	struct sdma_state *ss =
270		container_of(kref, struct sdma_state, kref);
271
272	complete(&ss->comp);
273}
274
275static void sdma_put(struct sdma_state *ss)
276{
277	kref_put(&ss->kref, sdma_complete);
278}
279
280static void sdma_finalput(struct sdma_state *ss)
281{
282	sdma_put(ss);
283	wait_for_completion(&ss->comp);
284}
285
286static inline void write_sde_csr(
287	struct sdma_engine *sde,
288	u32 offset0,
289	u64 value)
290{
291	write_kctxt_csr(sde->dd, sde->this_idx, offset0, value);
292}
293
294static inline u64 read_sde_csr(
295	struct sdma_engine *sde,
296	u32 offset0)
297{
298	return read_kctxt_csr(sde->dd, sde->this_idx, offset0);
299}
300
301/*
302 * sdma_wait_for_packet_egress() - wait for the VL FIFO occupancy for
303 * sdma engine 'sde' to drop to 0.
304 */
305static void sdma_wait_for_packet_egress(struct sdma_engine *sde,
306					int pause)
307{
308	u64 off = 8 * sde->this_idx;
309	struct hfi1_devdata *dd = sde->dd;
310	int lcnt = 0;
311	u64 reg_prev;
312	u64 reg = 0;
313
314	while (1) {
315		reg_prev = reg;
316		reg = read_csr(dd, off + SEND_EGRESS_SEND_DMA_STATUS);
317
318		reg &= SDMA_EGRESS_PACKET_OCCUPANCY_SMASK;
319		reg >>= SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT;
320		if (reg == 0)
321			break;
322		/* counter is reest if accupancy count changes */
323		if (reg != reg_prev)
324			lcnt = 0;
325		if (lcnt++ > 500) {
326			/* timed out - bounce the link */
327			dd_dev_err(dd, "%s: engine %u timeout waiting for packets to egress, remaining count %u, bouncing link\n",
328				   __func__, sde->this_idx, (u32)reg);
329			queue_work(dd->pport->link_wq,
330				   &dd->pport->link_bounce_work);
331			break;
332		}
333		udelay(1);
334	}
335}
336
337/*
338 * sdma_wait() - wait for packet egress to complete for all SDMA engines,
339 * and pause for credit return.
340 */
341void sdma_wait(struct hfi1_devdata *dd)
342{
343	int i;
344
345	for (i = 0; i < dd->num_sdma; i++) {
346		struct sdma_engine *sde = &dd->per_sdma[i];
347
348		sdma_wait_for_packet_egress(sde, 0);
349	}
350}
351
352static inline void sdma_set_desc_cnt(struct sdma_engine *sde, unsigned cnt)
353{
354	u64 reg;
355
356	if (!(sde->dd->flags & HFI1_HAS_SDMA_TIMEOUT))
357		return;
358	reg = cnt;
359	reg &= SD(DESC_CNT_CNT_MASK);
360	reg <<= SD(DESC_CNT_CNT_SHIFT);
361	write_sde_csr(sde, SD(DESC_CNT), reg);
362}
363
364static inline void complete_tx(struct sdma_engine *sde,
365			       struct sdma_txreq *tx,
366			       int res)
367{
368	/* protect against complete modifying */
369	struct iowait *wait = tx->wait;
370	callback_t complete = tx->complete;
371
372#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
373	trace_hfi1_sdma_out_sn(sde, tx->sn);
374	if (WARN_ON_ONCE(sde->head_sn != tx->sn))
375		dd_dev_err(sde->dd, "expected %llu got %llu\n",
376			   sde->head_sn, tx->sn);
377	sde->head_sn++;
378#endif
379	__sdma_txclean(sde->dd, tx);
380	if (complete)
381		(*complete)(tx, res);
382	if (iowait_sdma_dec(wait))
383		iowait_drain_wakeup(wait);
384}
385
386/*
387 * Complete all the sdma requests with a SDMA_TXREQ_S_ABORTED status
388 *
389 * Depending on timing there can be txreqs in two places:
390 * - in the descq ring
391 * - in the flush list
392 *
393 * To avoid ordering issues the descq ring needs to be flushed
394 * first followed by the flush list.
395 *
396 * This routine is called from two places
397 * - From a work queue item
398 * - Directly from the state machine just before setting the
399 *   state to running
400 *
401 * Must be called with head_lock held
402 *
403 */
404static void sdma_flush(struct sdma_engine *sde)
405{
406	struct sdma_txreq *txp, *txp_next;
407	LIST_HEAD(flushlist);
408	unsigned long flags;
409	uint seq;
410
411	/* flush from head to tail */
412	sdma_flush_descq(sde);
413	spin_lock_irqsave(&sde->flushlist_lock, flags);
414	/* copy flush list */
415	list_splice_init(&sde->flushlist, &flushlist);
416	spin_unlock_irqrestore(&sde->flushlist_lock, flags);
417	/* flush from flush list */
418	list_for_each_entry_safe(txp, txp_next, &flushlist, list)
419		complete_tx(sde, txp, SDMA_TXREQ_S_ABORTED);
420	/* wakeup QPs orphaned on the dmawait list */
421	do {
422		struct iowait *w, *nw;
423
424		seq = read_seqbegin(&sde->waitlock);
425		if (!list_empty(&sde->dmawait)) {
426			write_seqlock(&sde->waitlock);
427			list_for_each_entry_safe(w, nw, &sde->dmawait, list) {
428				if (w->wakeup) {
429					w->wakeup(w, SDMA_AVAIL_REASON);
430					list_del_init(&w->list);
431				}
432			}
433			write_sequnlock(&sde->waitlock);
434		}
435	} while (read_seqretry(&sde->waitlock, seq));
436}
437
438/*
439 * Fields a work request for flushing the descq ring
440 * and the flush list
441 *
442 * If the engine has been brought to running during
443 * the scheduling delay, the flush is ignored, assuming
444 * that the process of bringing the engine to running
445 * would have done this flush prior to going to running.
446 *
447 */
448static void sdma_field_flush(struct work_struct *work)
449{
450	unsigned long flags;
451	struct sdma_engine *sde =
452		container_of(work, struct sdma_engine, flush_worker);
453
454	write_seqlock_irqsave(&sde->head_lock, flags);
455	if (!__sdma_running(sde))
456		sdma_flush(sde);
457	write_sequnlock_irqrestore(&sde->head_lock, flags);
458}
459
460static void sdma_err_halt_wait(struct work_struct *work)
461{
462	struct sdma_engine *sde = container_of(work, struct sdma_engine,
463						err_halt_worker);
464	u64 statuscsr;
465	unsigned long timeout;
466
467	timeout = jiffies + msecs_to_jiffies(SDMA_ERR_HALT_TIMEOUT);
468	while (1) {
469		statuscsr = read_sde_csr(sde, SD(STATUS));
470		statuscsr &= SD(STATUS_ENG_HALTED_SMASK);
471		if (statuscsr)
472			break;
473		if (time_after(jiffies, timeout)) {
474			dd_dev_err(sde->dd,
475				   "SDMA engine %d - timeout waiting for engine to halt\n",
476				   sde->this_idx);
477			/*
478			 * Continue anyway.  This could happen if there was
479			 * an uncorrectable error in the wrong spot.
480			 */
481			break;
482		}
483		usleep_range(80, 120);
484	}
485
486	sdma_process_event(sde, sdma_event_e15_hw_halt_done);
487}
488
489static void sdma_err_progress_check_schedule(struct sdma_engine *sde)
490{
491	if (!is_bx(sde->dd) && HFI1_CAP_IS_KSET(SDMA_AHG)) {
492		unsigned index;
493		struct hfi1_devdata *dd = sde->dd;
494
495		for (index = 0; index < dd->num_sdma; index++) {
496			struct sdma_engine *curr_sdma = &dd->per_sdma[index];
497
498			if (curr_sdma != sde)
499				curr_sdma->progress_check_head =
500							curr_sdma->descq_head;
501		}
502		dd_dev_err(sde->dd,
503			   "SDMA engine %d - check scheduled\n",
504				sde->this_idx);
505		mod_timer(&sde->err_progress_check_timer, jiffies + 10);
506	}
507}
508
509static void sdma_err_progress_check(struct timer_list *t)
510{
511	unsigned index;
512	struct sdma_engine *sde = from_timer(sde, t, err_progress_check_timer);
513
514	dd_dev_err(sde->dd, "SDE progress check event\n");
515	for (index = 0; index < sde->dd->num_sdma; index++) {
516		struct sdma_engine *curr_sde = &sde->dd->per_sdma[index];
517		unsigned long flags;
518
519		/* check progress on each engine except the current one */
520		if (curr_sde == sde)
521			continue;
522		/*
523		 * We must lock interrupts when acquiring sde->lock,
524		 * to avoid a deadlock if interrupt triggers and spins on
525		 * the same lock on same CPU
526		 */
527		spin_lock_irqsave(&curr_sde->tail_lock, flags);
528		write_seqlock(&curr_sde->head_lock);
529
530		/* skip non-running queues */
531		if (curr_sde->state.current_state != sdma_state_s99_running) {
532			write_sequnlock(&curr_sde->head_lock);
533			spin_unlock_irqrestore(&curr_sde->tail_lock, flags);
534			continue;
535		}
536
537		if ((curr_sde->descq_head != curr_sde->descq_tail) &&
538		    (curr_sde->descq_head ==
539				curr_sde->progress_check_head))
540			__sdma_process_event(curr_sde,
541					     sdma_event_e90_sw_halted);
542		write_sequnlock(&curr_sde->head_lock);
543		spin_unlock_irqrestore(&curr_sde->tail_lock, flags);
544	}
545	schedule_work(&sde->err_halt_worker);
546}
547
548static void sdma_hw_clean_up_task(struct tasklet_struct *t)
549{
550	struct sdma_engine *sde = from_tasklet(sde, t,
551					       sdma_hw_clean_up_task);
552	u64 statuscsr;
553
554	while (1) {
555#ifdef CONFIG_SDMA_VERBOSITY
556		dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
557			   sde->this_idx, slashstrip(__FILE__), __LINE__,
558			__func__);
559#endif
560		statuscsr = read_sde_csr(sde, SD(STATUS));
561		statuscsr &= SD(STATUS_ENG_CLEANED_UP_SMASK);
562		if (statuscsr)
563			break;
564		udelay(10);
565	}
566
567	sdma_process_event(sde, sdma_event_e25_hw_clean_up_done);
568}
569
570static inline struct sdma_txreq *get_txhead(struct sdma_engine *sde)
571{
572	return sde->tx_ring[sde->tx_head & sde->sdma_mask];
573}
574
575/*
576 * flush ring for recovery
577 */
578static void sdma_flush_descq(struct sdma_engine *sde)
579{
580	u16 head, tail;
581	int progress = 0;
582	struct sdma_txreq *txp = get_txhead(sde);
583
584	/* The reason for some of the complexity of this code is that
585	 * not all descriptors have corresponding txps.  So, we have to
586	 * be able to skip over descs until we wander into the range of
587	 * the next txp on the list.
588	 */
589	head = sde->descq_head & sde->sdma_mask;
590	tail = sde->descq_tail & sde->sdma_mask;
591	while (head != tail) {
592		/* advance head, wrap if needed */
593		head = ++sde->descq_head & sde->sdma_mask;
594		/* if now past this txp's descs, do the callback */
595		if (txp && txp->next_descq_idx == head) {
596			/* remove from list */
597			sde->tx_ring[sde->tx_head++ & sde->sdma_mask] = NULL;
598			complete_tx(sde, txp, SDMA_TXREQ_S_ABORTED);
599			trace_hfi1_sdma_progress(sde, head, tail, txp);
600			txp = get_txhead(sde);
601		}
602		progress++;
603	}
604	if (progress)
605		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
606}
607
608static void sdma_sw_clean_up_task(struct tasklet_struct *t)
609{
610	struct sdma_engine *sde = from_tasklet(sde, t, sdma_sw_clean_up_task);
611	unsigned long flags;
612
613	spin_lock_irqsave(&sde->tail_lock, flags);
614	write_seqlock(&sde->head_lock);
615
616	/*
617	 * At this point, the following should always be true:
618	 * - We are halted, so no more descriptors are getting retired.
619	 * - We are not running, so no one is submitting new work.
620	 * - Only we can send the e40_sw_cleaned, so we can't start
621	 *   running again until we say so.  So, the active list and
622	 *   descq are ours to play with.
623	 */
624
625	/*
626	 * In the error clean up sequence, software clean must be called
627	 * before the hardware clean so we can use the hardware head in
628	 * the progress routine.  A hardware clean or SPC unfreeze will
629	 * reset the hardware head.
630	 *
631	 * Process all retired requests. The progress routine will use the
632	 * latest physical hardware head - we are not running so speed does
633	 * not matter.
634	 */
635	sdma_make_progress(sde, 0);
636
637	sdma_flush(sde);
638
639	/*
640	 * Reset our notion of head and tail.
641	 * Note that the HW registers have been reset via an earlier
642	 * clean up.
643	 */
644	sde->descq_tail = 0;
645	sde->descq_head = 0;
646	sde->desc_avail = sdma_descq_freecnt(sde);
647	*sde->head_dma = 0;
648
649	__sdma_process_event(sde, sdma_event_e40_sw_cleaned);
650
651	write_sequnlock(&sde->head_lock);
652	spin_unlock_irqrestore(&sde->tail_lock, flags);
653}
654
655static void sdma_sw_tear_down(struct sdma_engine *sde)
656{
657	struct sdma_state *ss = &sde->state;
658
659	/* Releasing this reference means the state machine has stopped. */
660	sdma_put(ss);
661
662	/* stop waiting for all unfreeze events to complete */
663	atomic_set(&sde->dd->sdma_unfreeze_count, -1);
664	wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
665}
666
667static void sdma_start_hw_clean_up(struct sdma_engine *sde)
668{
669	tasklet_hi_schedule(&sde->sdma_hw_clean_up_task);
670}
671
672static void sdma_set_state(struct sdma_engine *sde,
673			   enum sdma_states next_state)
674{
675	struct sdma_state *ss = &sde->state;
676	const struct sdma_set_state_action *action = sdma_action_table;
677	unsigned op = 0;
678
679	trace_hfi1_sdma_state(
680		sde,
681		sdma_state_names[ss->current_state],
682		sdma_state_names[next_state]);
683
684	/* debugging bookkeeping */
685	ss->previous_state = ss->current_state;
686	ss->previous_op = ss->current_op;
687	ss->current_state = next_state;
688
689	if (ss->previous_state != sdma_state_s99_running &&
690	    next_state == sdma_state_s99_running)
691		sdma_flush(sde);
692
693	if (action[next_state].op_enable)
694		op |= SDMA_SENDCTRL_OP_ENABLE;
695
696	if (action[next_state].op_intenable)
697		op |= SDMA_SENDCTRL_OP_INTENABLE;
698
699	if (action[next_state].op_halt)
700		op |= SDMA_SENDCTRL_OP_HALT;
701
702	if (action[next_state].op_cleanup)
703		op |= SDMA_SENDCTRL_OP_CLEANUP;
704
705	if (action[next_state].go_s99_running_tofalse)
706		ss->go_s99_running = 0;
707
708	if (action[next_state].go_s99_running_totrue)
709		ss->go_s99_running = 1;
710
711	ss->current_op = op;
712	sdma_sendctrl(sde, ss->current_op);
713}
714
715/**
716 * sdma_get_descq_cnt() - called when device probed
717 *
718 * Return a validated descq count.
719 *
720 * This is currently only used in the verbs initialization to build the tx
721 * list.
722 *
723 * This will probably be deleted in favor of a more scalable approach to
724 * alloc tx's.
725 *
726 */
727u16 sdma_get_descq_cnt(void)
728{
729	u16 count = sdma_descq_cnt;
730
731	if (!count)
732		return SDMA_DESCQ_CNT;
733	/* count must be a power of 2 greater than 64 and less than
734	 * 32768.   Otherwise return default.
735	 */
736	if (!is_power_of_2(count))
737		return SDMA_DESCQ_CNT;
738	if (count < 64 || count > 32768)
739		return SDMA_DESCQ_CNT;
740	return count;
741}
742
743/**
744 * sdma_engine_get_vl() - return vl for a given sdma engine
745 * @sde: sdma engine
746 *
747 * This function returns the vl mapped to a given engine, or an error if
748 * the mapping can't be found. The mapping fields are protected by RCU.
749 */
750int sdma_engine_get_vl(struct sdma_engine *sde)
751{
752	struct hfi1_devdata *dd = sde->dd;
753	struct sdma_vl_map *m;
754	u8 vl;
755
756	if (sde->this_idx >= TXE_NUM_SDMA_ENGINES)
757		return -EINVAL;
758
759	rcu_read_lock();
760	m = rcu_dereference(dd->sdma_map);
761	if (unlikely(!m)) {
762		rcu_read_unlock();
763		return -EINVAL;
764	}
765	vl = m->engine_to_vl[sde->this_idx];
766	rcu_read_unlock();
767
768	return vl;
769}
770
771/**
772 * sdma_select_engine_vl() - select sdma engine
773 * @dd: devdata
774 * @selector: a spreading factor
775 * @vl: this vl
776 *
777 *
778 * This function returns an engine based on the selector and a vl.  The
779 * mapping fields are protected by RCU.
780 */
781struct sdma_engine *sdma_select_engine_vl(
782	struct hfi1_devdata *dd,
783	u32 selector,
784	u8 vl)
785{
786	struct sdma_vl_map *m;
787	struct sdma_map_elem *e;
788	struct sdma_engine *rval;
789
790	/* NOTE This should only happen if SC->VL changed after the initial
791	 *      checks on the QP/AH
792	 *      Default will return engine 0 below
793	 */
794	if (vl >= num_vls) {
795		rval = NULL;
796		goto done;
797	}
798
799	rcu_read_lock();
800	m = rcu_dereference(dd->sdma_map);
801	if (unlikely(!m)) {
802		rcu_read_unlock();
803		return &dd->per_sdma[0];
804	}
805	e = m->map[vl & m->mask];
806	rval = e->sde[selector & e->mask];
807	rcu_read_unlock();
808
809done:
810	rval =  !rval ? &dd->per_sdma[0] : rval;
811	trace_hfi1_sdma_engine_select(dd, selector, vl, rval->this_idx);
812	return rval;
813}
814
815/**
816 * sdma_select_engine_sc() - select sdma engine
817 * @dd: devdata
818 * @selector: a spreading factor
819 * @sc5: the 5 bit sc
820 *
821 *
822 * This function returns an engine based on the selector and an sc.
823 */
824struct sdma_engine *sdma_select_engine_sc(
825	struct hfi1_devdata *dd,
826	u32 selector,
827	u8 sc5)
828{
829	u8 vl = sc_to_vlt(dd, sc5);
830
831	return sdma_select_engine_vl(dd, selector, vl);
832}
833
834struct sdma_rht_map_elem {
835	u32 mask;
836	u8 ctr;
837	struct sdma_engine *sde[];
838};
839
840struct sdma_rht_node {
841	unsigned long cpu_id;
842	struct sdma_rht_map_elem *map[HFI1_MAX_VLS_SUPPORTED];
843	struct rhash_head node;
844};
845
846#define NR_CPUS_HINT 192
847
848static const struct rhashtable_params sdma_rht_params = {
849	.nelem_hint = NR_CPUS_HINT,
850	.head_offset = offsetof(struct sdma_rht_node, node),
851	.key_offset = offsetof(struct sdma_rht_node, cpu_id),
852	.key_len = sizeof_field(struct sdma_rht_node, cpu_id),
853	.max_size = NR_CPUS,
854	.min_size = 8,
855	.automatic_shrinking = true,
856};
857
858/*
859 * sdma_select_user_engine() - select sdma engine based on user setup
860 * @dd: devdata
861 * @selector: a spreading factor
862 * @vl: this vl
863 *
864 * This function returns an sdma engine for a user sdma request.
865 * User defined sdma engine affinity setting is honored when applicable,
866 * otherwise system default sdma engine mapping is used. To ensure correct
867 * ordering, the mapping from <selector, vl> to sde must remain unchanged.
868 */
869struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd,
870					    u32 selector, u8 vl)
871{
872	struct sdma_rht_node *rht_node;
873	struct sdma_engine *sde = NULL;
874	unsigned long cpu_id;
875
876	/*
877	 * To ensure that always the same sdma engine(s) will be
878	 * selected make sure the process is pinned to this CPU only.
879	 */
880	if (current->nr_cpus_allowed != 1)
881		goto out;
882
883	rcu_read_lock();
884	cpu_id = smp_processor_id();
885	rht_node = rhashtable_lookup(dd->sdma_rht, &cpu_id,
886				     sdma_rht_params);
887
888	if (rht_node && rht_node->map[vl]) {
889		struct sdma_rht_map_elem *map = rht_node->map[vl];
890
891		sde = map->sde[selector & map->mask];
892	}
893	rcu_read_unlock();
894
895	if (sde)
896		return sde;
897
898out:
899	return sdma_select_engine_vl(dd, selector, vl);
900}
901
902static void sdma_populate_sde_map(struct sdma_rht_map_elem *map)
903{
904	int i;
905
906	for (i = 0; i < roundup_pow_of_two(map->ctr ? : 1) - map->ctr; i++)
907		map->sde[map->ctr + i] = map->sde[i];
908}
909
910static void sdma_cleanup_sde_map(struct sdma_rht_map_elem *map,
911				 struct sdma_engine *sde)
912{
913	unsigned int i, pow;
914
915	/* only need to check the first ctr entries for a match */
916	for (i = 0; i < map->ctr; i++) {
917		if (map->sde[i] == sde) {
918			memmove(&map->sde[i], &map->sde[i + 1],
919				(map->ctr - i - 1) * sizeof(map->sde[0]));
920			map->ctr--;
921			pow = roundup_pow_of_two(map->ctr ? : 1);
922			map->mask = pow - 1;
923			sdma_populate_sde_map(map);
924			break;
925		}
926	}
927}
928
929/*
930 * Prevents concurrent reads and writes of the sdma engine cpu_mask
931 */
932static DEFINE_MUTEX(process_to_sde_mutex);
933
934ssize_t sdma_set_cpu_to_sde_map(struct sdma_engine *sde, const char *buf,
935				size_t count)
936{
937	struct hfi1_devdata *dd = sde->dd;
938	cpumask_var_t mask, new_mask;
939	unsigned long cpu;
940	int ret, vl, sz;
941	struct sdma_rht_node *rht_node;
942
943	vl = sdma_engine_get_vl(sde);
944	if (unlikely(vl < 0 || vl >= ARRAY_SIZE(rht_node->map)))
945		return -EINVAL;
946
947	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
948	if (!ret)
949		return -ENOMEM;
950
951	ret = zalloc_cpumask_var(&new_mask, GFP_KERNEL);
952	if (!ret) {
953		free_cpumask_var(mask);
954		return -ENOMEM;
955	}
956	ret = cpulist_parse(buf, mask);
957	if (ret)
958		goto out_free;
959
960	if (!cpumask_subset(mask, cpu_online_mask)) {
961		dd_dev_warn(sde->dd, "Invalid CPU mask\n");
962		ret = -EINVAL;
963		goto out_free;
964	}
965
966	sz = sizeof(struct sdma_rht_map_elem) +
967			(TXE_NUM_SDMA_ENGINES * sizeof(struct sdma_engine *));
968
969	mutex_lock(&process_to_sde_mutex);
970
971	for_each_cpu(cpu, mask) {
972		/* Check if we have this already mapped */
973		if (cpumask_test_cpu(cpu, &sde->cpu_mask)) {
974			cpumask_set_cpu(cpu, new_mask);
975			continue;
976		}
977
978		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
979						  sdma_rht_params);
980		if (!rht_node) {
981			rht_node = kzalloc(sizeof(*rht_node), GFP_KERNEL);
982			if (!rht_node) {
983				ret = -ENOMEM;
984				goto out;
985			}
986
987			rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
988			if (!rht_node->map[vl]) {
989				kfree(rht_node);
990				ret = -ENOMEM;
991				goto out;
992			}
993			rht_node->cpu_id = cpu;
994			rht_node->map[vl]->mask = 0;
995			rht_node->map[vl]->ctr = 1;
996			rht_node->map[vl]->sde[0] = sde;
997
998			ret = rhashtable_insert_fast(dd->sdma_rht,
999						     &rht_node->node,
1000						     sdma_rht_params);
1001			if (ret) {
1002				kfree(rht_node->map[vl]);
1003				kfree(rht_node);
1004				dd_dev_err(sde->dd, "Failed to set process to sde affinity for cpu %lu\n",
1005					   cpu);
1006				goto out;
1007			}
1008
1009		} else {
1010			int ctr, pow;
1011
1012			/* Add new user mappings */
1013			if (!rht_node->map[vl])
1014				rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
1015
1016			if (!rht_node->map[vl]) {
1017				ret = -ENOMEM;
1018				goto out;
1019			}
1020
1021			rht_node->map[vl]->ctr++;
1022			ctr = rht_node->map[vl]->ctr;
1023			rht_node->map[vl]->sde[ctr - 1] = sde;
1024			pow = roundup_pow_of_two(ctr);
1025			rht_node->map[vl]->mask = pow - 1;
1026
1027			/* Populate the sde map table */
1028			sdma_populate_sde_map(rht_node->map[vl]);
1029		}
1030		cpumask_set_cpu(cpu, new_mask);
1031	}
1032
1033	/* Clean up old mappings */
1034	for_each_cpu(cpu, cpu_online_mask) {
1035		struct sdma_rht_node *rht_node;
1036
1037		/* Don't cleanup sdes that are set in the new mask */
1038		if (cpumask_test_cpu(cpu, mask))
1039			continue;
1040
1041		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
1042						  sdma_rht_params);
1043		if (rht_node) {
1044			bool empty = true;
1045			int i;
1046
1047			/* Remove mappings for old sde */
1048			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1049				if (rht_node->map[i])
1050					sdma_cleanup_sde_map(rht_node->map[i],
1051							     sde);
1052
1053			/* Free empty hash table entries */
1054			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1055				if (!rht_node->map[i])
1056					continue;
1057
1058				if (rht_node->map[i]->ctr) {
1059					empty = false;
1060					break;
1061				}
1062			}
1063
1064			if (empty) {
1065				ret = rhashtable_remove_fast(dd->sdma_rht,
1066							     &rht_node->node,
1067							     sdma_rht_params);
1068				WARN_ON(ret);
1069
1070				for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1071					kfree(rht_node->map[i]);
1072
1073				kfree(rht_node);
1074			}
1075		}
1076	}
1077
1078	cpumask_copy(&sde->cpu_mask, new_mask);
1079out:
1080	mutex_unlock(&process_to_sde_mutex);
1081out_free:
1082	free_cpumask_var(mask);
1083	free_cpumask_var(new_mask);
1084	return ret ? : strnlen(buf, PAGE_SIZE);
1085}
1086
1087ssize_t sdma_get_cpu_to_sde_map(struct sdma_engine *sde, char *buf)
1088{
1089	mutex_lock(&process_to_sde_mutex);
1090	if (cpumask_empty(&sde->cpu_mask))
1091		snprintf(buf, PAGE_SIZE, "%s\n", "empty");
1092	else
1093		cpumap_print_to_pagebuf(true, buf, &sde->cpu_mask);
1094	mutex_unlock(&process_to_sde_mutex);
1095	return strnlen(buf, PAGE_SIZE);
1096}
1097
1098static void sdma_rht_free(void *ptr, void *arg)
1099{
1100	struct sdma_rht_node *rht_node = ptr;
1101	int i;
1102
1103	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1104		kfree(rht_node->map[i]);
1105
1106	kfree(rht_node);
1107}
1108
1109/**
1110 * sdma_seqfile_dump_cpu_list() - debugfs dump the cpu to sdma mappings
1111 * @s: seq file
1112 * @dd: hfi1_devdata
1113 * @cpuid: cpu id
1114 *
1115 * This routine dumps the process to sde mappings per cpu
1116 */
1117void sdma_seqfile_dump_cpu_list(struct seq_file *s,
1118				struct hfi1_devdata *dd,
1119				unsigned long cpuid)
1120{
1121	struct sdma_rht_node *rht_node;
1122	int i, j;
1123
1124	rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpuid,
1125					  sdma_rht_params);
1126	if (!rht_node)
1127		return;
1128
1129	seq_printf(s, "cpu%3lu: ", cpuid);
1130	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1131		if (!rht_node->map[i] || !rht_node->map[i]->ctr)
1132			continue;
1133
1134		seq_printf(s, " vl%d: [", i);
1135
1136		for (j = 0; j < rht_node->map[i]->ctr; j++) {
1137			if (!rht_node->map[i]->sde[j])
1138				continue;
1139
1140			if (j > 0)
1141				seq_puts(s, ",");
1142
1143			seq_printf(s, " sdma%2d",
1144				   rht_node->map[i]->sde[j]->this_idx);
1145		}
1146		seq_puts(s, " ]");
1147	}
1148
1149	seq_puts(s, "\n");
1150}
1151
1152/*
1153 * Free the indicated map struct
1154 */
1155static void sdma_map_free(struct sdma_vl_map *m)
1156{
1157	int i;
1158
1159	for (i = 0; m && i < m->actual_vls; i++)
1160		kfree(m->map[i]);
1161	kfree(m);
1162}
1163
1164/*
1165 * Handle RCU callback
1166 */
1167static void sdma_map_rcu_callback(struct rcu_head *list)
1168{
1169	struct sdma_vl_map *m = container_of(list, struct sdma_vl_map, list);
1170
1171	sdma_map_free(m);
1172}
1173
1174/**
1175 * sdma_map_init - called when # vls change
1176 * @dd: hfi1_devdata
1177 * @port: port number
1178 * @num_vls: number of vls
1179 * @vl_engines: per vl engine mapping (optional)
1180 *
1181 * This routine changes the mapping based on the number of vls.
1182 *
1183 * vl_engines is used to specify a non-uniform vl/engine loading. NULL
1184 * implies auto computing the loading and giving each VLs a uniform
1185 * distribution of engines per VL.
1186 *
1187 * The auto algorithm computes the sde_per_vl and the number of extra
1188 * engines.  Any extra engines are added from the last VL on down.
1189 *
1190 * rcu locking is used here to control access to the mapping fields.
1191 *
1192 * If either the num_vls or num_sdma are non-power of 2, the array sizes
1193 * in the struct sdma_vl_map and the struct sdma_map_elem are rounded
1194 * up to the next highest power of 2 and the first entry is reused
1195 * in a round robin fashion.
1196 *
1197 * If an error occurs the map change is not done and the mapping is
1198 * not changed.
1199 *
1200 */
1201int sdma_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_engines)
1202{
1203	int i, j;
1204	int extra, sde_per_vl;
1205	int engine = 0;
1206	u8 lvl_engines[OPA_MAX_VLS];
1207	struct sdma_vl_map *oldmap, *newmap;
1208
1209	if (!(dd->flags & HFI1_HAS_SEND_DMA))
1210		return 0;
1211
1212	if (!vl_engines) {
1213		/* truncate divide */
1214		sde_per_vl = dd->num_sdma / num_vls;
1215		/* extras */
1216		extra = dd->num_sdma % num_vls;
1217		vl_engines = lvl_engines;
1218		/* add extras from last vl down */
1219		for (i = num_vls - 1; i >= 0; i--, extra--)
1220			vl_engines[i] = sde_per_vl + (extra > 0 ? 1 : 0);
1221	}
1222	/* build new map */
1223	newmap = kzalloc(
1224		sizeof(struct sdma_vl_map) +
1225			roundup_pow_of_two(num_vls) *
1226			sizeof(struct sdma_map_elem *),
1227		GFP_KERNEL);
1228	if (!newmap)
1229		goto bail;
1230	newmap->actual_vls = num_vls;
1231	newmap->vls = roundup_pow_of_two(num_vls);
1232	newmap->mask = (1 << ilog2(newmap->vls)) - 1;
1233	/* initialize back-map */
1234	for (i = 0; i < TXE_NUM_SDMA_ENGINES; i++)
1235		newmap->engine_to_vl[i] = -1;
1236	for (i = 0; i < newmap->vls; i++) {
1237		/* save for wrap around */
1238		int first_engine = engine;
1239
1240		if (i < newmap->actual_vls) {
1241			int sz = roundup_pow_of_two(vl_engines[i]);
1242
1243			/* only allocate once */
1244			newmap->map[i] = kzalloc(
1245				sizeof(struct sdma_map_elem) +
1246					sz * sizeof(struct sdma_engine *),
1247				GFP_KERNEL);
1248			if (!newmap->map[i])
1249				goto bail;
1250			newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
1251			/* assign engines */
1252			for (j = 0; j < sz; j++) {
1253				newmap->map[i]->sde[j] =
1254					&dd->per_sdma[engine];
1255				if (++engine >= first_engine + vl_engines[i])
1256					/* wrap back to first engine */
1257					engine = first_engine;
1258			}
1259			/* assign back-map */
1260			for (j = 0; j < vl_engines[i]; j++)
1261				newmap->engine_to_vl[first_engine + j] = i;
1262		} else {
1263			/* just re-use entry without allocating */
1264			newmap->map[i] = newmap->map[i % num_vls];
1265		}
1266		engine = first_engine + vl_engines[i];
1267	}
1268	/* newmap in hand, save old map */
1269	spin_lock_irq(&dd->sde_map_lock);
1270	oldmap = rcu_dereference_protected(dd->sdma_map,
1271					   lockdep_is_held(&dd->sde_map_lock));
1272
1273	/* publish newmap */
1274	rcu_assign_pointer(dd->sdma_map, newmap);
1275
1276	spin_unlock_irq(&dd->sde_map_lock);
1277	/* success, free any old map after grace period */
1278	if (oldmap)
1279		call_rcu(&oldmap->list, sdma_map_rcu_callback);
1280	return 0;
1281bail:
1282	/* free any partial allocation */
1283	sdma_map_free(newmap);
1284	return -ENOMEM;
1285}
1286
1287/**
1288 * sdma_clean()  Clean up allocated memory
1289 * @dd:          struct hfi1_devdata
1290 * @num_engines: num sdma engines
1291 *
1292 * This routine can be called regardless of the success of
1293 * sdma_init()
1294 */
1295void sdma_clean(struct hfi1_devdata *dd, size_t num_engines)
1296{
1297	size_t i;
1298	struct sdma_engine *sde;
1299
1300	if (dd->sdma_pad_dma) {
1301		dma_free_coherent(&dd->pcidev->dev, SDMA_PAD,
1302				  (void *)dd->sdma_pad_dma,
1303				  dd->sdma_pad_phys);
1304		dd->sdma_pad_dma = NULL;
1305		dd->sdma_pad_phys = 0;
1306	}
1307	if (dd->sdma_heads_dma) {
1308		dma_free_coherent(&dd->pcidev->dev, dd->sdma_heads_size,
1309				  (void *)dd->sdma_heads_dma,
1310				  dd->sdma_heads_phys);
1311		dd->sdma_heads_dma = NULL;
1312		dd->sdma_heads_phys = 0;
1313	}
1314	for (i = 0; dd->per_sdma && i < num_engines; ++i) {
1315		sde = &dd->per_sdma[i];
1316
1317		sde->head_dma = NULL;
1318		sde->head_phys = 0;
1319
1320		if (sde->descq) {
1321			dma_free_coherent(
1322				&dd->pcidev->dev,
1323				sde->descq_cnt * sizeof(u64[2]),
1324				sde->descq,
1325				sde->descq_phys
1326			);
1327			sde->descq = NULL;
1328			sde->descq_phys = 0;
1329		}
1330		kvfree(sde->tx_ring);
1331		sde->tx_ring = NULL;
1332	}
1333	if (rcu_access_pointer(dd->sdma_map)) {
1334		spin_lock_irq(&dd->sde_map_lock);
1335		sdma_map_free(rcu_access_pointer(dd->sdma_map));
1336		RCU_INIT_POINTER(dd->sdma_map, NULL);
1337		spin_unlock_irq(&dd->sde_map_lock);
1338		synchronize_rcu();
1339	}
1340	kfree(dd->per_sdma);
1341	dd->per_sdma = NULL;
1342
1343	if (dd->sdma_rht) {
1344		rhashtable_free_and_destroy(dd->sdma_rht, sdma_rht_free, NULL);
1345		kfree(dd->sdma_rht);
1346		dd->sdma_rht = NULL;
1347	}
1348}
1349
1350/**
1351 * sdma_init() - called when device probed
1352 * @dd: hfi1_devdata
1353 * @port: port number (currently only zero)
1354 *
1355 * Initializes each sde and its csrs.
1356 * Interrupts are not required to be enabled.
1357 *
1358 * Returns:
1359 * 0 - success, -errno on failure
1360 */
1361int sdma_init(struct hfi1_devdata *dd, u8 port)
1362{
1363	unsigned this_idx;
1364	struct sdma_engine *sde;
1365	struct rhashtable *tmp_sdma_rht;
1366	u16 descq_cnt;
1367	void *curr_head;
1368	struct hfi1_pportdata *ppd = dd->pport + port;
1369	u32 per_sdma_credits;
1370	uint idle_cnt = sdma_idle_cnt;
1371	size_t num_engines = chip_sdma_engines(dd);
1372	int ret = -ENOMEM;
1373
1374	if (!HFI1_CAP_IS_KSET(SDMA)) {
1375		HFI1_CAP_CLEAR(SDMA_AHG);
1376		return 0;
1377	}
1378	if (mod_num_sdma &&
1379	    /* can't exceed chip support */
1380	    mod_num_sdma <= chip_sdma_engines(dd) &&
1381	    /* count must be >= vls */
1382	    mod_num_sdma >= num_vls)
1383		num_engines = mod_num_sdma;
1384
1385	dd_dev_info(dd, "SDMA mod_num_sdma: %u\n", mod_num_sdma);
1386	dd_dev_info(dd, "SDMA chip_sdma_engines: %u\n", chip_sdma_engines(dd));
1387	dd_dev_info(dd, "SDMA chip_sdma_mem_size: %u\n",
1388		    chip_sdma_mem_size(dd));
1389
1390	per_sdma_credits =
1391		chip_sdma_mem_size(dd) / (num_engines * SDMA_BLOCK_SIZE);
1392
1393	/* set up freeze waitqueue */
1394	init_waitqueue_head(&dd->sdma_unfreeze_wq);
1395	atomic_set(&dd->sdma_unfreeze_count, 0);
1396
1397	descq_cnt = sdma_get_descq_cnt();
1398	dd_dev_info(dd, "SDMA engines %zu descq_cnt %u\n",
1399		    num_engines, descq_cnt);
1400
1401	/* alloc memory for array of send engines */
1402	dd->per_sdma = kcalloc_node(num_engines, sizeof(*dd->per_sdma),
1403				    GFP_KERNEL, dd->node);
1404	if (!dd->per_sdma)
1405		return ret;
1406
1407	idle_cnt = ns_to_cclock(dd, idle_cnt);
1408	if (idle_cnt)
1409		dd->default_desc1 =
1410			SDMA_DESC1_HEAD_TO_HOST_FLAG;
1411	else
1412		dd->default_desc1 =
1413			SDMA_DESC1_INT_REQ_FLAG;
1414
1415	if (!sdma_desct_intr)
1416		sdma_desct_intr = SDMA_DESC_INTR;
1417
1418	/* Allocate memory for SendDMA descriptor FIFOs */
1419	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1420		sde = &dd->per_sdma[this_idx];
1421		sde->dd = dd;
1422		sde->ppd = ppd;
1423		sde->this_idx = this_idx;
1424		sde->descq_cnt = descq_cnt;
1425		sde->desc_avail = sdma_descq_freecnt(sde);
1426		sde->sdma_shift = ilog2(descq_cnt);
1427		sde->sdma_mask = (1 << sde->sdma_shift) - 1;
1428
1429		/* Create a mask specifically for each interrupt source */
1430		sde->int_mask = (u64)1 << (0 * TXE_NUM_SDMA_ENGINES +
1431					   this_idx);
1432		sde->progress_mask = (u64)1 << (1 * TXE_NUM_SDMA_ENGINES +
1433						this_idx);
1434		sde->idle_mask = (u64)1 << (2 * TXE_NUM_SDMA_ENGINES +
1435					    this_idx);
1436		/* Create a combined mask to cover all 3 interrupt sources */
1437		sde->imask = sde->int_mask | sde->progress_mask |
1438			     sde->idle_mask;
1439
1440		spin_lock_init(&sde->tail_lock);
1441		seqlock_init(&sde->head_lock);
1442		spin_lock_init(&sde->senddmactrl_lock);
1443		spin_lock_init(&sde->flushlist_lock);
1444		seqlock_init(&sde->waitlock);
1445		/* insure there is always a zero bit */
1446		sde->ahg_bits = 0xfffffffe00000000ULL;
1447
1448		sdma_set_state(sde, sdma_state_s00_hw_down);
1449
1450		/* set up reference counting */
1451		kref_init(&sde->state.kref);
1452		init_completion(&sde->state.comp);
1453
1454		INIT_LIST_HEAD(&sde->flushlist);
1455		INIT_LIST_HEAD(&sde->dmawait);
1456
1457		sde->tail_csr =
1458			get_kctxt_csr_addr(dd, this_idx, SD(TAIL));
1459
1460		tasklet_setup(&sde->sdma_hw_clean_up_task,
1461			      sdma_hw_clean_up_task);
1462		tasklet_setup(&sde->sdma_sw_clean_up_task,
1463			      sdma_sw_clean_up_task);
1464		INIT_WORK(&sde->err_halt_worker, sdma_err_halt_wait);
1465		INIT_WORK(&sde->flush_worker, sdma_field_flush);
1466
1467		sde->progress_check_head = 0;
1468
1469		timer_setup(&sde->err_progress_check_timer,
1470			    sdma_err_progress_check, 0);
1471
1472		sde->descq = dma_alloc_coherent(&dd->pcidev->dev,
1473						descq_cnt * sizeof(u64[2]),
1474						&sde->descq_phys, GFP_KERNEL);
1475		if (!sde->descq)
1476			goto bail;
1477		sde->tx_ring =
1478			kvzalloc_node(array_size(descq_cnt,
1479						 sizeof(struct sdma_txreq *)),
1480				      GFP_KERNEL, dd->node);
1481		if (!sde->tx_ring)
1482			goto bail;
1483	}
1484
1485	dd->sdma_heads_size = L1_CACHE_BYTES * num_engines;
1486	/* Allocate memory for DMA of head registers to memory */
1487	dd->sdma_heads_dma = dma_alloc_coherent(&dd->pcidev->dev,
1488						dd->sdma_heads_size,
1489						&dd->sdma_heads_phys,
1490						GFP_KERNEL);
1491	if (!dd->sdma_heads_dma) {
1492		dd_dev_err(dd, "failed to allocate SendDMA head memory\n");
1493		goto bail;
1494	}
1495
1496	/* Allocate memory for pad */
1497	dd->sdma_pad_dma = dma_alloc_coherent(&dd->pcidev->dev, SDMA_PAD,
1498					      &dd->sdma_pad_phys, GFP_KERNEL);
1499	if (!dd->sdma_pad_dma) {
1500		dd_dev_err(dd, "failed to allocate SendDMA pad memory\n");
1501		goto bail;
1502	}
1503
1504	/* assign each engine to different cacheline and init registers */
1505	curr_head = (void *)dd->sdma_heads_dma;
1506	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1507		unsigned long phys_offset;
1508
1509		sde = &dd->per_sdma[this_idx];
1510
1511		sde->head_dma = curr_head;
1512		curr_head += L1_CACHE_BYTES;
1513		phys_offset = (unsigned long)sde->head_dma -
1514			      (unsigned long)dd->sdma_heads_dma;
1515		sde->head_phys = dd->sdma_heads_phys + phys_offset;
1516		init_sdma_regs(sde, per_sdma_credits, idle_cnt);
1517	}
1518	dd->flags |= HFI1_HAS_SEND_DMA;
1519	dd->flags |= idle_cnt ? HFI1_HAS_SDMA_TIMEOUT : 0;
1520	dd->num_sdma = num_engines;
1521	ret = sdma_map_init(dd, port, ppd->vls_operational, NULL);
1522	if (ret < 0)
1523		goto bail;
1524
1525	tmp_sdma_rht = kzalloc(sizeof(*tmp_sdma_rht), GFP_KERNEL);
1526	if (!tmp_sdma_rht) {
1527		ret = -ENOMEM;
1528		goto bail;
1529	}
1530
1531	ret = rhashtable_init(tmp_sdma_rht, &sdma_rht_params);
1532	if (ret < 0) {
1533		kfree(tmp_sdma_rht);
1534		goto bail;
1535	}
1536
1537	dd->sdma_rht = tmp_sdma_rht;
1538
1539	dd_dev_info(dd, "SDMA num_sdma: %u\n", dd->num_sdma);
1540	return 0;
1541
1542bail:
1543	sdma_clean(dd, num_engines);
1544	return ret;
1545}
1546
1547/**
1548 * sdma_all_running() - called when the link goes up
1549 * @dd: hfi1_devdata
1550 *
1551 * This routine moves all engines to the running state.
1552 */
1553void sdma_all_running(struct hfi1_devdata *dd)
1554{
1555	struct sdma_engine *sde;
1556	unsigned int i;
1557
1558	/* move all engines to running */
1559	for (i = 0; i < dd->num_sdma; ++i) {
1560		sde = &dd->per_sdma[i];
1561		sdma_process_event(sde, sdma_event_e30_go_running);
1562	}
1563}
1564
1565/**
1566 * sdma_all_idle() - called when the link goes down
1567 * @dd: hfi1_devdata
1568 *
1569 * This routine moves all engines to the idle state.
1570 */
1571void sdma_all_idle(struct hfi1_devdata *dd)
1572{
1573	struct sdma_engine *sde;
1574	unsigned int i;
1575
1576	/* idle all engines */
1577	for (i = 0; i < dd->num_sdma; ++i) {
1578		sde = &dd->per_sdma[i];
1579		sdma_process_event(sde, sdma_event_e70_go_idle);
1580	}
1581}
1582
1583/**
1584 * sdma_start() - called to kick off state processing for all engines
1585 * @dd: hfi1_devdata
1586 *
1587 * This routine is for kicking off the state processing for all required
1588 * sdma engines.  Interrupts need to be working at this point.
1589 *
1590 */
1591void sdma_start(struct hfi1_devdata *dd)
1592{
1593	unsigned i;
1594	struct sdma_engine *sde;
1595
1596	/* kick off the engines state processing */
1597	for (i = 0; i < dd->num_sdma; ++i) {
1598		sde = &dd->per_sdma[i];
1599		sdma_process_event(sde, sdma_event_e10_go_hw_start);
1600	}
1601}
1602
1603/**
1604 * sdma_exit() - used when module is removed
1605 * @dd: hfi1_devdata
1606 */
1607void sdma_exit(struct hfi1_devdata *dd)
1608{
1609	unsigned this_idx;
1610	struct sdma_engine *sde;
1611
1612	for (this_idx = 0; dd->per_sdma && this_idx < dd->num_sdma;
1613			++this_idx) {
1614		sde = &dd->per_sdma[this_idx];
1615		if (!list_empty(&sde->dmawait))
1616			dd_dev_err(dd, "sde %u: dmawait list not empty!\n",
1617				   sde->this_idx);
1618		sdma_process_event(sde, sdma_event_e00_go_hw_down);
1619
1620		del_timer_sync(&sde->err_progress_check_timer);
1621
1622		/*
1623		 * This waits for the state machine to exit so it is not
1624		 * necessary to kill the sdma_sw_clean_up_task to make sure
1625		 * it is not running.
1626		 */
1627		sdma_finalput(&sde->state);
1628	}
1629}
1630
1631/*
1632 * unmap the indicated descriptor
1633 */
1634static inline void sdma_unmap_desc(
1635	struct hfi1_devdata *dd,
1636	struct sdma_desc *descp)
1637{
1638	switch (sdma_mapping_type(descp)) {
1639	case SDMA_MAP_SINGLE:
1640		dma_unmap_single(&dd->pcidev->dev, sdma_mapping_addr(descp),
1641				 sdma_mapping_len(descp), DMA_TO_DEVICE);
1642		break;
1643	case SDMA_MAP_PAGE:
1644		dma_unmap_page(&dd->pcidev->dev, sdma_mapping_addr(descp),
1645			       sdma_mapping_len(descp), DMA_TO_DEVICE);
1646		break;
1647	}
1648
1649	if (descp->pinning_ctx && descp->ctx_put)
1650		descp->ctx_put(descp->pinning_ctx);
1651	descp->pinning_ctx = NULL;
1652}
1653
1654/*
1655 * return the mode as indicated by the first
1656 * descriptor in the tx.
1657 */
1658static inline u8 ahg_mode(struct sdma_txreq *tx)
1659{
1660	return (tx->descp[0].qw[1] & SDMA_DESC1_HEADER_MODE_SMASK)
1661		>> SDMA_DESC1_HEADER_MODE_SHIFT;
1662}
1663
1664/**
1665 * __sdma_txclean() - clean tx of mappings, descp *kmalloc's
1666 * @dd: hfi1_devdata for unmapping
1667 * @tx: tx request to clean
1668 *
1669 * This is used in the progress routine to clean the tx or
1670 * by the ULP to toss an in-process tx build.
1671 *
1672 * The code can be called multiple times without issue.
1673 *
1674 */
1675void __sdma_txclean(
1676	struct hfi1_devdata *dd,
1677	struct sdma_txreq *tx)
1678{
1679	u16 i;
1680
1681	if (tx->num_desc) {
1682		u8 skip = 0, mode = ahg_mode(tx);
1683
1684		/* unmap first */
1685		sdma_unmap_desc(dd, &tx->descp[0]);
1686		/* determine number of AHG descriptors to skip */
1687		if (mode > SDMA_AHG_APPLY_UPDATE1)
1688			skip = mode >> 1;
1689		for (i = 1 + skip; i < tx->num_desc; i++)
1690			sdma_unmap_desc(dd, &tx->descp[i]);
1691		tx->num_desc = 0;
1692	}
1693	kfree(tx->coalesce_buf);
1694	tx->coalesce_buf = NULL;
1695	/* kmalloc'ed descp */
1696	if (unlikely(tx->desc_limit > ARRAY_SIZE(tx->descs))) {
1697		tx->desc_limit = ARRAY_SIZE(tx->descs);
1698		kfree(tx->descp);
1699	}
1700}
1701
1702static inline u16 sdma_gethead(struct sdma_engine *sde)
1703{
1704	struct hfi1_devdata *dd = sde->dd;
1705	int use_dmahead;
1706	u16 hwhead;
1707
1708#ifdef CONFIG_SDMA_VERBOSITY
1709	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1710		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1711#endif
1712
1713retry:
1714	use_dmahead = HFI1_CAP_IS_KSET(USE_SDMA_HEAD) && __sdma_running(sde) &&
1715					(dd->flags & HFI1_HAS_SDMA_TIMEOUT);
1716	hwhead = use_dmahead ?
1717		(u16)le64_to_cpu(*sde->head_dma) :
1718		(u16)read_sde_csr(sde, SD(HEAD));
1719
1720	if (unlikely(HFI1_CAP_IS_KSET(SDMA_HEAD_CHECK))) {
1721		u16 cnt;
1722		u16 swtail;
1723		u16 swhead;
1724		int sane;
1725
1726		swhead = sde->descq_head & sde->sdma_mask;
1727		/* this code is really bad for cache line trading */
1728		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1729		cnt = sde->descq_cnt;
1730
1731		if (swhead < swtail)
1732			/* not wrapped */
1733			sane = (hwhead >= swhead) & (hwhead <= swtail);
1734		else if (swhead > swtail)
1735			/* wrapped around */
1736			sane = ((hwhead >= swhead) && (hwhead < cnt)) ||
1737				(hwhead <= swtail);
1738		else
1739			/* empty */
1740			sane = (hwhead == swhead);
1741
1742		if (unlikely(!sane)) {
1743			dd_dev_err(dd, "SDMA(%u) bad head (%s) hwhd=%hu swhd=%hu swtl=%hu cnt=%hu\n",
1744				   sde->this_idx,
1745				   use_dmahead ? "dma" : "kreg",
1746				   hwhead, swhead, swtail, cnt);
1747			if (use_dmahead) {
1748				/* try one more time, using csr */
1749				use_dmahead = 0;
1750				goto retry;
1751			}
1752			/* proceed as if no progress */
1753			hwhead = swhead;
1754		}
1755	}
1756	return hwhead;
1757}
1758
1759/*
1760 * This is called when there are send DMA descriptors that might be
1761 * available.
1762 *
1763 * This is called with head_lock held.
1764 */
1765static void sdma_desc_avail(struct sdma_engine *sde, uint avail)
1766{
1767	struct iowait *wait, *nw, *twait;
1768	struct iowait *waits[SDMA_WAIT_BATCH_SIZE];
1769	uint i, n = 0, seq, tidx = 0;
1770
1771#ifdef CONFIG_SDMA_VERBOSITY
1772	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n", sde->this_idx,
1773		   slashstrip(__FILE__), __LINE__, __func__);
1774	dd_dev_err(sde->dd, "avail: %u\n", avail);
1775#endif
1776
1777	do {
1778		seq = read_seqbegin(&sde->waitlock);
1779		if (!list_empty(&sde->dmawait)) {
1780			/* at least one item */
1781			write_seqlock(&sde->waitlock);
1782			/* Harvest waiters wanting DMA descriptors */
1783			list_for_each_entry_safe(
1784					wait,
1785					nw,
1786					&sde->dmawait,
1787					list) {
1788				u32 num_desc;
1789
1790				if (!wait->wakeup)
1791					continue;
1792				if (n == ARRAY_SIZE(waits))
1793					break;
1794				iowait_init_priority(wait);
1795				num_desc = iowait_get_all_desc(wait);
1796				if (num_desc > avail)
1797					break;
1798				avail -= num_desc;
1799				/* Find the top-priority wait memeber */
1800				if (n) {
1801					twait = waits[tidx];
1802					tidx =
1803					    iowait_priority_update_top(wait,
1804								       twait,
1805								       n,
1806								       tidx);
1807				}
1808				list_del_init(&wait->list);
1809				waits[n++] = wait;
1810			}
1811			write_sequnlock(&sde->waitlock);
1812			break;
1813		}
1814	} while (read_seqretry(&sde->waitlock, seq));
1815
1816	/* Schedule the top-priority entry first */
1817	if (n)
1818		waits[tidx]->wakeup(waits[tidx], SDMA_AVAIL_REASON);
1819
1820	for (i = 0; i < n; i++)
1821		if (i != tidx)
1822			waits[i]->wakeup(waits[i], SDMA_AVAIL_REASON);
1823}
1824
1825/* head_lock must be held */
1826static void sdma_make_progress(struct sdma_engine *sde, u64 status)
1827{
1828	struct sdma_txreq *txp = NULL;
1829	int progress = 0;
1830	u16 hwhead, swhead;
1831	int idle_check_done = 0;
1832
1833	hwhead = sdma_gethead(sde);
1834
1835	/* The reason for some of the complexity of this code is that
1836	 * not all descriptors have corresponding txps.  So, we have to
1837	 * be able to skip over descs until we wander into the range of
1838	 * the next txp on the list.
1839	 */
1840
1841retry:
1842	txp = get_txhead(sde);
1843	swhead = sde->descq_head & sde->sdma_mask;
1844	trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1845	while (swhead != hwhead) {
1846		/* advance head, wrap if needed */
1847		swhead = ++sde->descq_head & sde->sdma_mask;
1848
1849		/* if now past this txp's descs, do the callback */
1850		if (txp && txp->next_descq_idx == swhead) {
1851			/* remove from list */
1852			sde->tx_ring[sde->tx_head++ & sde->sdma_mask] = NULL;
1853			complete_tx(sde, txp, SDMA_TXREQ_S_OK);
1854			/* see if there is another txp */
1855			txp = get_txhead(sde);
1856		}
1857		trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1858		progress++;
1859	}
1860
1861	/*
1862	 * The SDMA idle interrupt is not guaranteed to be ordered with respect
1863	 * to updates to the the dma_head location in host memory. The head
1864	 * value read might not be fully up to date. If there are pending
1865	 * descriptors and the SDMA idle interrupt fired then read from the
1866	 * CSR SDMA head instead to get the latest value from the hardware.
1867	 * The hardware SDMA head should be read at most once in this invocation
1868	 * of sdma_make_progress(..) which is ensured by idle_check_done flag
1869	 */
1870	if ((status & sde->idle_mask) && !idle_check_done) {
1871		u16 swtail;
1872
1873		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1874		if (swtail != hwhead) {
1875			hwhead = (u16)read_sde_csr(sde, SD(HEAD));
1876			idle_check_done = 1;
1877			goto retry;
1878		}
1879	}
1880
1881	sde->last_status = status;
1882	if (progress)
1883		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
1884}
1885
1886/*
1887 * sdma_engine_interrupt() - interrupt handler for engine
1888 * @sde: sdma engine
1889 * @status: sdma interrupt reason
1890 *
1891 * Status is a mask of the 3 possible interrupts for this engine.  It will
1892 * contain bits _only_ for this SDMA engine.  It will contain at least one
1893 * bit, it may contain more.
1894 */
1895void sdma_engine_interrupt(struct sdma_engine *sde, u64 status)
1896{
1897	trace_hfi1_sdma_engine_interrupt(sde, status);
1898	write_seqlock(&sde->head_lock);
1899	sdma_set_desc_cnt(sde, sdma_desct_intr);
1900	if (status & sde->idle_mask)
1901		sde->idle_int_cnt++;
1902	else if (status & sde->progress_mask)
1903		sde->progress_int_cnt++;
1904	else if (status & sde->int_mask)
1905		sde->sdma_int_cnt++;
1906	sdma_make_progress(sde, status);
1907	write_sequnlock(&sde->head_lock);
1908}
1909
1910/**
1911 * sdma_engine_error() - error handler for engine
1912 * @sde: sdma engine
1913 * @status: sdma interrupt reason
1914 */
1915void sdma_engine_error(struct sdma_engine *sde, u64 status)
1916{
1917	unsigned long flags;
1918
1919#ifdef CONFIG_SDMA_VERBOSITY
1920	dd_dev_err(sde->dd, "CONFIG SDMA(%u) error status 0x%llx state %s\n",
1921		   sde->this_idx,
1922		   (unsigned long long)status,
1923		   sdma_state_names[sde->state.current_state]);
1924#endif
1925	spin_lock_irqsave(&sde->tail_lock, flags);
1926	write_seqlock(&sde->head_lock);
1927	if (status & ALL_SDMA_ENG_HALT_ERRS)
1928		__sdma_process_event(sde, sdma_event_e60_hw_halted);
1929	if (status & ~SD(ENG_ERR_STATUS_SDMA_HALT_ERR_SMASK)) {
1930		dd_dev_err(sde->dd,
1931			   "SDMA (%u) engine error: 0x%llx state %s\n",
1932			   sde->this_idx,
1933			   (unsigned long long)status,
1934			   sdma_state_names[sde->state.current_state]);
1935		dump_sdma_state(sde);
1936	}
1937	write_sequnlock(&sde->head_lock);
1938	spin_unlock_irqrestore(&sde->tail_lock, flags);
1939}
1940
1941static void sdma_sendctrl(struct sdma_engine *sde, unsigned op)
1942{
1943	u64 set_senddmactrl = 0;
1944	u64 clr_senddmactrl = 0;
1945	unsigned long flags;
1946
1947#ifdef CONFIG_SDMA_VERBOSITY
1948	dd_dev_err(sde->dd, "CONFIG SDMA(%u) senddmactrl E=%d I=%d H=%d C=%d\n",
1949		   sde->this_idx,
1950		   (op & SDMA_SENDCTRL_OP_ENABLE) ? 1 : 0,
1951		   (op & SDMA_SENDCTRL_OP_INTENABLE) ? 1 : 0,
1952		   (op & SDMA_SENDCTRL_OP_HALT) ? 1 : 0,
1953		   (op & SDMA_SENDCTRL_OP_CLEANUP) ? 1 : 0);
1954#endif
1955
1956	if (op & SDMA_SENDCTRL_OP_ENABLE)
1957		set_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1958	else
1959		clr_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1960
1961	if (op & SDMA_SENDCTRL_OP_INTENABLE)
1962		set_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1963	else
1964		clr_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1965
1966	if (op & SDMA_SENDCTRL_OP_HALT)
1967		set_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1968	else
1969		clr_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1970
1971	spin_lock_irqsave(&sde->senddmactrl_lock, flags);
1972
1973	sde->p_senddmactrl |= set_senddmactrl;
1974	sde->p_senddmactrl &= ~clr_senddmactrl;
1975
1976	if (op & SDMA_SENDCTRL_OP_CLEANUP)
1977		write_sde_csr(sde, SD(CTRL),
1978			      sde->p_senddmactrl |
1979			      SD(CTRL_SDMA_CLEANUP_SMASK));
1980	else
1981		write_sde_csr(sde, SD(CTRL), sde->p_senddmactrl);
1982
1983	spin_unlock_irqrestore(&sde->senddmactrl_lock, flags);
1984
1985#ifdef CONFIG_SDMA_VERBOSITY
1986	sdma_dumpstate(sde);
1987#endif
1988}
1989
1990static void sdma_setlengen(struct sdma_engine *sde)
1991{
1992#ifdef CONFIG_SDMA_VERBOSITY
1993	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1994		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1995#endif
1996
1997	/*
1998	 * Set SendDmaLenGen and clear-then-set the MSB of the generation
1999	 * count to enable generation checking and load the internal
2000	 * generation counter.
2001	 */
2002	write_sde_csr(sde, SD(LEN_GEN),
2003		      (sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT));
2004	write_sde_csr(sde, SD(LEN_GEN),
2005		      ((sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT)) |
2006		      (4ULL << SD(LEN_GEN_GENERATION_SHIFT)));
2007}
2008
2009static inline void sdma_update_tail(struct sdma_engine *sde, u16 tail)
2010{
2011	/* Commit writes to memory and advance the tail on the chip */
2012	smp_wmb(); /* see get_txhead() */
2013	writeq(tail, sde->tail_csr);
2014}
2015
2016/*
2017 * This is called when changing to state s10_hw_start_up_halt_wait as
2018 * a result of send buffer errors or send DMA descriptor errors.
2019 */
2020static void sdma_hw_start_up(struct sdma_engine *sde)
2021{
2022	u64 reg;
2023
2024#ifdef CONFIG_SDMA_VERBOSITY
2025	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2026		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2027#endif
2028
2029	sdma_setlengen(sde);
2030	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2031	*sde->head_dma = 0;
2032
2033	reg = SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_MASK) <<
2034	      SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_SHIFT);
2035	write_sde_csr(sde, SD(ENG_ERR_CLEAR), reg);
2036}
2037
2038/*
2039 * set_sdma_integrity
2040 *
2041 * Set the SEND_DMA_CHECK_ENABLE register for send DMA engine 'sde'.
2042 */
2043static void set_sdma_integrity(struct sdma_engine *sde)
2044{
2045	struct hfi1_devdata *dd = sde->dd;
2046
2047	write_sde_csr(sde, SD(CHECK_ENABLE),
2048		      hfi1_pkt_base_sdma_integrity(dd));
2049}
2050
2051static void init_sdma_regs(
2052	struct sdma_engine *sde,
2053	u32 credits,
2054	uint idle_cnt)
2055{
2056	u8 opval, opmask;
2057#ifdef CONFIG_SDMA_VERBOSITY
2058	struct hfi1_devdata *dd = sde->dd;
2059
2060	dd_dev_err(dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2061		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2062#endif
2063
2064	write_sde_csr(sde, SD(BASE_ADDR), sde->descq_phys);
2065	sdma_setlengen(sde);
2066	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2067	write_sde_csr(sde, SD(RELOAD_CNT), idle_cnt);
2068	write_sde_csr(sde, SD(DESC_CNT), 0);
2069	write_sde_csr(sde, SD(HEAD_ADDR), sde->head_phys);
2070	write_sde_csr(sde, SD(MEMORY),
2071		      ((u64)credits << SD(MEMORY_SDMA_MEMORY_CNT_SHIFT)) |
2072		      ((u64)(credits * sde->this_idx) <<
2073		       SD(MEMORY_SDMA_MEMORY_INDEX_SHIFT)));
2074	write_sde_csr(sde, SD(ENG_ERR_MASK), ~0ull);
2075	set_sdma_integrity(sde);
2076	opmask = OPCODE_CHECK_MASK_DISABLED;
2077	opval = OPCODE_CHECK_VAL_DISABLED;
2078	write_sde_csr(sde, SD(CHECK_OPCODE),
2079		      (opmask << SEND_CTXT_CHECK_OPCODE_MASK_SHIFT) |
2080		      (opval << SEND_CTXT_CHECK_OPCODE_VALUE_SHIFT));
2081}
2082
2083#ifdef CONFIG_SDMA_VERBOSITY
2084
2085#define sdma_dumpstate_helper0(reg) do { \
2086		csr = read_csr(sde->dd, reg); \
2087		dd_dev_err(sde->dd, "%36s     0x%016llx\n", #reg, csr); \
2088	} while (0)
2089
2090#define sdma_dumpstate_helper(reg) do { \
2091		csr = read_sde_csr(sde, reg); \
2092		dd_dev_err(sde->dd, "%36s[%02u] 0x%016llx\n", \
2093			#reg, sde->this_idx, csr); \
2094	} while (0)
2095
2096#define sdma_dumpstate_helper2(reg) do { \
2097		csr = read_csr(sde->dd, reg + (8 * i)); \
2098		dd_dev_err(sde->dd, "%33s_%02u     0x%016llx\n", \
2099				#reg, i, csr); \
2100	} while (0)
2101
2102void sdma_dumpstate(struct sdma_engine *sde)
2103{
2104	u64 csr;
2105	unsigned i;
2106
2107	sdma_dumpstate_helper(SD(CTRL));
2108	sdma_dumpstate_helper(SD(STATUS));
2109	sdma_dumpstate_helper0(SD(ERR_STATUS));
2110	sdma_dumpstate_helper0(SD(ERR_MASK));
2111	sdma_dumpstate_helper(SD(ENG_ERR_STATUS));
2112	sdma_dumpstate_helper(SD(ENG_ERR_MASK));
2113
2114	for (i = 0; i < CCE_NUM_INT_CSRS; ++i) {
2115		sdma_dumpstate_helper2(CCE_INT_STATUS);
2116		sdma_dumpstate_helper2(CCE_INT_MASK);
2117		sdma_dumpstate_helper2(CCE_INT_BLOCKED);
2118	}
2119
2120	sdma_dumpstate_helper(SD(TAIL));
2121	sdma_dumpstate_helper(SD(HEAD));
2122	sdma_dumpstate_helper(SD(PRIORITY_THLD));
2123	sdma_dumpstate_helper(SD(IDLE_CNT));
2124	sdma_dumpstate_helper(SD(RELOAD_CNT));
2125	sdma_dumpstate_helper(SD(DESC_CNT));
2126	sdma_dumpstate_helper(SD(DESC_FETCHED_CNT));
2127	sdma_dumpstate_helper(SD(MEMORY));
2128	sdma_dumpstate_helper0(SD(ENGINES));
2129	sdma_dumpstate_helper0(SD(MEM_SIZE));
2130	/* sdma_dumpstate_helper(SEND_EGRESS_SEND_DMA_STATUS);  */
2131	sdma_dumpstate_helper(SD(BASE_ADDR));
2132	sdma_dumpstate_helper(SD(LEN_GEN));
2133	sdma_dumpstate_helper(SD(HEAD_ADDR));
2134	sdma_dumpstate_helper(SD(CHECK_ENABLE));
2135	sdma_dumpstate_helper(SD(CHECK_VL));
2136	sdma_dumpstate_helper(SD(CHECK_JOB_KEY));
2137	sdma_dumpstate_helper(SD(CHECK_PARTITION_KEY));
2138	sdma_dumpstate_helper(SD(CHECK_SLID));
2139	sdma_dumpstate_helper(SD(CHECK_OPCODE));
2140}
2141#endif
2142
2143static void dump_sdma_state(struct sdma_engine *sde)
2144{
2145	struct hw_sdma_desc *descqp;
2146	u64 desc[2];
2147	u64 addr;
2148	u8 gen;
2149	u16 len;
2150	u16 head, tail, cnt;
2151
2152	head = sde->descq_head & sde->sdma_mask;
2153	tail = sde->descq_tail & sde->sdma_mask;
2154	cnt = sdma_descq_freecnt(sde);
2155
2156	dd_dev_err(sde->dd,
2157		   "SDMA (%u) descq_head: %u descq_tail: %u freecnt: %u FLE %d\n",
2158		   sde->this_idx, head, tail, cnt,
2159		   !list_empty(&sde->flushlist));
2160
2161	/* print info for each entry in the descriptor queue */
2162	while (head != tail) {
2163		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2164
2165		descqp = &sde->descq[head];
2166		desc[0] = le64_to_cpu(descqp->qw[0]);
2167		desc[1] = le64_to_cpu(descqp->qw[1]);
2168		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2169		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2170				'H' : '-';
2171		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2172		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2173		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2174			& SDMA_DESC0_PHY_ADDR_MASK;
2175		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2176			& SDMA_DESC1_GENERATION_MASK;
2177		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2178			& SDMA_DESC0_BYTE_COUNT_MASK;
2179		dd_dev_err(sde->dd,
2180			   "SDMA sdmadesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2181			   head, flags, addr, gen, len);
2182		dd_dev_err(sde->dd,
2183			   "\tdesc0:0x%016llx desc1 0x%016llx\n",
2184			   desc[0], desc[1]);
2185		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2186			dd_dev_err(sde->dd,
2187				   "\taidx: %u amode: %u alen: %u\n",
2188				   (u8)((desc[1] &
2189					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2190					SDMA_DESC1_HEADER_INDEX_SHIFT),
2191				   (u8)((desc[1] &
2192					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2193					SDMA_DESC1_HEADER_MODE_SHIFT),
2194				   (u8)((desc[1] &
2195					 SDMA_DESC1_HEADER_DWS_SMASK) >>
2196					SDMA_DESC1_HEADER_DWS_SHIFT));
2197		head++;
2198		head &= sde->sdma_mask;
2199	}
2200}
2201
2202#define SDE_FMT \
2203	"SDE %u CPU %d STE %s C 0x%llx S 0x%016llx E 0x%llx T(HW) 0x%llx T(SW) 0x%x H(HW) 0x%llx H(SW) 0x%x H(D) 0x%llx DM 0x%llx GL 0x%llx R 0x%llx LIS 0x%llx AHGI 0x%llx TXT %u TXH %u DT %u DH %u FLNE %d DQF %u SLC 0x%llx\n"
2204/**
2205 * sdma_seqfile_dump_sde() - debugfs dump of sde
2206 * @s: seq file
2207 * @sde: send dma engine to dump
2208 *
2209 * This routine dumps the sde to the indicated seq file.
2210 */
2211void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *sde)
2212{
2213	u16 head, tail;
2214	struct hw_sdma_desc *descqp;
2215	u64 desc[2];
2216	u64 addr;
2217	u8 gen;
2218	u16 len;
2219
2220	head = sde->descq_head & sde->sdma_mask;
2221	tail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
2222	seq_printf(s, SDE_FMT, sde->this_idx,
2223		   sde->cpu,
2224		   sdma_state_name(sde->state.current_state),
2225		   (unsigned long long)read_sde_csr(sde, SD(CTRL)),
2226		   (unsigned long long)read_sde_csr(sde, SD(STATUS)),
2227		   (unsigned long long)read_sde_csr(sde, SD(ENG_ERR_STATUS)),
2228		   (unsigned long long)read_sde_csr(sde, SD(TAIL)), tail,
2229		   (unsigned long long)read_sde_csr(sde, SD(HEAD)), head,
2230		   (unsigned long long)le64_to_cpu(*sde->head_dma),
2231		   (unsigned long long)read_sde_csr(sde, SD(MEMORY)),
2232		   (unsigned long long)read_sde_csr(sde, SD(LEN_GEN)),
2233		   (unsigned long long)read_sde_csr(sde, SD(RELOAD_CNT)),
2234		   (unsigned long long)sde->last_status,
2235		   (unsigned long long)sde->ahg_bits,
2236		   sde->tx_tail,
2237		   sde->tx_head,
2238		   sde->descq_tail,
2239		   sde->descq_head,
2240		   !list_empty(&sde->flushlist),
2241		   sde->descq_full_count,
2242		   (unsigned long long)read_sde_csr(sde, SEND_DMA_CHECK_SLID));
2243
2244	/* print info for each entry in the descriptor queue */
2245	while (head != tail) {
2246		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2247
2248		descqp = &sde->descq[head];
2249		desc[0] = le64_to_cpu(descqp->qw[0]);
2250		desc[1] = le64_to_cpu(descqp->qw[1]);
2251		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2252		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2253				'H' : '-';
2254		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2255		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2256		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2257			& SDMA_DESC0_PHY_ADDR_MASK;
2258		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2259			& SDMA_DESC1_GENERATION_MASK;
2260		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2261			& SDMA_DESC0_BYTE_COUNT_MASK;
2262		seq_printf(s,
2263			   "\tdesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2264			   head, flags, addr, gen, len);
2265		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2266			seq_printf(s, "\t\tahgidx: %u ahgmode: %u\n",
2267				   (u8)((desc[1] &
2268					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2269					SDMA_DESC1_HEADER_INDEX_SHIFT),
2270				   (u8)((desc[1] &
2271					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2272					SDMA_DESC1_HEADER_MODE_SHIFT));
2273		head = (head + 1) & sde->sdma_mask;
2274	}
2275}
2276
2277/*
2278 * add the generation number into
2279 * the qw1 and return
2280 */
2281static inline u64 add_gen(struct sdma_engine *sde, u64 qw1)
2282{
2283	u8 generation = (sde->descq_tail >> sde->sdma_shift) & 3;
2284
2285	qw1 &= ~SDMA_DESC1_GENERATION_SMASK;
2286	qw1 |= ((u64)generation & SDMA_DESC1_GENERATION_MASK)
2287			<< SDMA_DESC1_GENERATION_SHIFT;
2288	return qw1;
2289}
2290
2291/*
2292 * This routine submits the indicated tx
2293 *
2294 * Space has already been guaranteed and
2295 * tail side of ring is locked.
2296 *
2297 * The hardware tail update is done
2298 * in the caller and that is facilitated
2299 * by returning the new tail.
2300 *
2301 * There is special case logic for ahg
2302 * to not add the generation number for
2303 * up to 2 descriptors that follow the
2304 * first descriptor.
2305 *
2306 */
2307static inline u16 submit_tx(struct sdma_engine *sde, struct sdma_txreq *tx)
2308{
2309	int i;
2310	u16 tail;
2311	struct sdma_desc *descp = tx->descp;
2312	u8 skip = 0, mode = ahg_mode(tx);
2313
2314	tail = sde->descq_tail & sde->sdma_mask;
2315	sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2316	sde->descq[tail].qw[1] = cpu_to_le64(add_gen(sde, descp->qw[1]));
2317	trace_hfi1_sdma_descriptor(sde, descp->qw[0], descp->qw[1],
2318				   tail, &sde->descq[tail]);
2319	tail = ++sde->descq_tail & sde->sdma_mask;
2320	descp++;
2321	if (mode > SDMA_AHG_APPLY_UPDATE1)
2322		skip = mode >> 1;
2323	for (i = 1; i < tx->num_desc; i++, descp++) {
2324		u64 qw1;
2325
2326		sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2327		if (skip) {
2328			/* edits don't have generation */
2329			qw1 = descp->qw[1];
2330			skip--;
2331		} else {
2332			/* replace generation with real one for non-edits */
2333			qw1 = add_gen(sde, descp->qw[1]);
2334		}
2335		sde->descq[tail].qw[1] = cpu_to_le64(qw1);
2336		trace_hfi1_sdma_descriptor(sde, descp->qw[0], qw1,
2337					   tail, &sde->descq[tail]);
2338		tail = ++sde->descq_tail & sde->sdma_mask;
2339	}
2340	tx->next_descq_idx = tail;
2341#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2342	tx->sn = sde->tail_sn++;
2343	trace_hfi1_sdma_in_sn(sde, tx->sn);
2344	WARN_ON_ONCE(sde->tx_ring[sde->tx_tail & sde->sdma_mask]);
2345#endif
2346	sde->tx_ring[sde->tx_tail++ & sde->sdma_mask] = tx;
2347	sde->desc_avail -= tx->num_desc;
2348	return tail;
2349}
2350
2351/*
2352 * Check for progress
2353 */
2354static int sdma_check_progress(
2355	struct sdma_engine *sde,
2356	struct iowait_work *wait,
2357	struct sdma_txreq *tx,
2358	bool pkts_sent)
2359{
2360	int ret;
2361
2362	sde->desc_avail = sdma_descq_freecnt(sde);
2363	if (tx->num_desc <= sde->desc_avail)
2364		return -EAGAIN;
2365	/* pulse the head_lock */
2366	if (wait && iowait_ioww_to_iow(wait)->sleep) {
2367		unsigned seq;
2368
2369		seq = raw_seqcount_begin(
2370			(const seqcount_t *)&sde->head_lock.seqcount);
2371		ret = wait->iow->sleep(sde, wait, tx, seq, pkts_sent);
2372		if (ret == -EAGAIN)
2373			sde->desc_avail = sdma_descq_freecnt(sde);
2374	} else {
2375		ret = -EBUSY;
2376	}
2377	return ret;
2378}
2379
2380/**
2381 * sdma_send_txreq() - submit a tx req to ring
2382 * @sde: sdma engine to use
2383 * @wait: SE wait structure to use when full (may be NULL)
2384 * @tx: sdma_txreq to submit
2385 * @pkts_sent: has any packet been sent yet?
2386 *
2387 * The call submits the tx into the ring.  If a iowait structure is non-NULL
2388 * the packet will be queued to the list in wait.
2389 *
2390 * Return:
2391 * 0 - Success, -EINVAL - sdma_txreq incomplete, -EBUSY - no space in
2392 * ring (wait == NULL)
2393 * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2394 */
2395int sdma_send_txreq(struct sdma_engine *sde,
2396		    struct iowait_work *wait,
2397		    struct sdma_txreq *tx,
2398		    bool pkts_sent)
2399{
2400	int ret = 0;
2401	u16 tail;
2402	unsigned long flags;
2403
2404	/* user should have supplied entire packet */
2405	if (unlikely(tx->tlen))
2406		return -EINVAL;
2407	tx->wait = iowait_ioww_to_iow(wait);
2408	spin_lock_irqsave(&sde->tail_lock, flags);
2409retry:
2410	if (unlikely(!__sdma_running(sde)))
2411		goto unlock_noconn;
2412	if (unlikely(tx->num_desc > sde->desc_avail))
2413		goto nodesc;
2414	tail = submit_tx(sde, tx);
2415	if (wait)
2416		iowait_sdma_inc(iowait_ioww_to_iow(wait));
2417	sdma_update_tail(sde, tail);
2418unlock:
2419	spin_unlock_irqrestore(&sde->tail_lock, flags);
2420	return ret;
2421unlock_noconn:
2422	if (wait)
2423		iowait_sdma_inc(iowait_ioww_to_iow(wait));
2424	tx->next_descq_idx = 0;
2425#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2426	tx->sn = sde->tail_sn++;
2427	trace_hfi1_sdma_in_sn(sde, tx->sn);
2428#endif
2429	spin_lock(&sde->flushlist_lock);
2430	list_add_tail(&tx->list, &sde->flushlist);
2431	spin_unlock(&sde->flushlist_lock);
2432	iowait_inc_wait_count(wait, tx->num_desc);
2433	queue_work_on(sde->cpu, system_highpri_wq, &sde->flush_worker);
2434	ret = -ECOMM;
2435	goto unlock;
2436nodesc:
2437	ret = sdma_check_progress(sde, wait, tx, pkts_sent);
2438	if (ret == -EAGAIN) {
2439		ret = 0;
2440		goto retry;
2441	}
2442	sde->descq_full_count++;
2443	goto unlock;
2444}
2445
2446/**
2447 * sdma_send_txlist() - submit a list of tx req to ring
2448 * @sde: sdma engine to use
2449 * @wait: SE wait structure to use when full (may be NULL)
2450 * @tx_list: list of sdma_txreqs to submit
2451 * @count: pointer to a u16 which, after return will contain the total number of
2452 *         sdma_txreqs removed from the tx_list. This will include sdma_txreqs
2453 *         whose SDMA descriptors are submitted to the ring and the sdma_txreqs
2454 *         which are added to SDMA engine flush list if the SDMA engine state is
2455 *         not running.
2456 *
2457 * The call submits the list into the ring.
2458 *
2459 * If the iowait structure is non-NULL and not equal to the iowait list
2460 * the unprocessed part of the list  will be appended to the list in wait.
2461 *
2462 * In all cases, the tx_list will be updated so the head of the tx_list is
2463 * the list of descriptors that have yet to be transmitted.
2464 *
2465 * The intent of this call is to provide a more efficient
2466 * way of submitting multiple packets to SDMA while holding the tail
2467 * side locking.
2468 *
2469 * Return:
2470 * 0 - Success,
2471 * -EINVAL - sdma_txreq incomplete, -EBUSY - no space in ring (wait == NULL)
2472 * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2473 */
2474int sdma_send_txlist(struct sdma_engine *sde, struct iowait_work *wait,
2475		     struct list_head *tx_list, u16 *count_out)
2476{
2477	struct sdma_txreq *tx, *tx_next;
2478	int ret = 0;
2479	unsigned long flags;
2480	u16 tail = INVALID_TAIL;
2481	u32 submit_count = 0, flush_count = 0, total_count;
2482
2483	spin_lock_irqsave(&sde->tail_lock, flags);
2484retry:
2485	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2486		tx->wait = iowait_ioww_to_iow(wait);
2487		if (unlikely(!__sdma_running(sde)))
2488			goto unlock_noconn;
2489		if (unlikely(tx->num_desc > sde->desc_avail))
2490			goto nodesc;
2491		if (unlikely(tx->tlen)) {
2492			ret = -EINVAL;
2493			goto update_tail;
2494		}
2495		list_del_init(&tx->list);
2496		tail = submit_tx(sde, tx);
2497		submit_count++;
2498		if (tail != INVALID_TAIL &&
2499		    (submit_count & SDMA_TAIL_UPDATE_THRESH) == 0) {
2500			sdma_update_tail(sde, tail);
2501			tail = INVALID_TAIL;
2502		}
2503	}
2504update_tail:
2505	total_count = submit_count + flush_count;
2506	if (wait) {
2507		iowait_sdma_add(iowait_ioww_to_iow(wait), total_count);
2508		iowait_starve_clear(submit_count > 0,
2509				    iowait_ioww_to_iow(wait));
2510	}
2511	if (tail != INVALID_TAIL)
2512		sdma_update_tail(sde, tail);
2513	spin_unlock_irqrestore(&sde->tail_lock, flags);
2514	*count_out = total_count;
2515	return ret;
2516unlock_noconn:
2517	spin_lock(&sde->flushlist_lock);
2518	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2519		tx->wait = iowait_ioww_to_iow(wait);
2520		list_del_init(&tx->list);
2521		tx->next_descq_idx = 0;
2522#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2523		tx->sn = sde->tail_sn++;
2524		trace_hfi1_sdma_in_sn(sde, tx->sn);
2525#endif
2526		list_add_tail(&tx->list, &sde->flushlist);
2527		flush_count++;
2528		iowait_inc_wait_count(wait, tx->num_desc);
2529	}
2530	spin_unlock(&sde->flushlist_lock);
2531	queue_work_on(sde->cpu, system_highpri_wq, &sde->flush_worker);
2532	ret = -ECOMM;
2533	goto update_tail;
2534nodesc:
2535	ret = sdma_check_progress(sde, wait, tx, submit_count > 0);
2536	if (ret == -EAGAIN) {
2537		ret = 0;
2538		goto retry;
2539	}
2540	sde->descq_full_count++;
2541	goto update_tail;
2542}
2543
2544static void sdma_process_event(struct sdma_engine *sde, enum sdma_events event)
2545{
2546	unsigned long flags;
2547
2548	spin_lock_irqsave(&sde->tail_lock, flags);
2549	write_seqlock(&sde->head_lock);
2550
2551	__sdma_process_event(sde, event);
2552
2553	if (sde->state.current_state == sdma_state_s99_running)
2554		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
2555
2556	write_sequnlock(&sde->head_lock);
2557	spin_unlock_irqrestore(&sde->tail_lock, flags);
2558}
2559
2560static void __sdma_process_event(struct sdma_engine *sde,
2561				 enum sdma_events event)
2562{
2563	struct sdma_state *ss = &sde->state;
2564	int need_progress = 0;
2565
2566	/* CONFIG SDMA temporary */
2567#ifdef CONFIG_SDMA_VERBOSITY
2568	dd_dev_err(sde->dd, "CONFIG SDMA(%u) [%s] %s\n", sde->this_idx,
2569		   sdma_state_names[ss->current_state],
2570		   sdma_event_names[event]);
2571#endif
2572
2573	switch (ss->current_state) {
2574	case sdma_state_s00_hw_down:
2575		switch (event) {
2576		case sdma_event_e00_go_hw_down:
2577			break;
2578		case sdma_event_e30_go_running:
2579			/*
2580			 * If down, but running requested (usually result
2581			 * of link up, then we need to start up.
2582			 * This can happen when hw down is requested while
2583			 * bringing the link up with traffic active on
2584			 * 7220, e.g.
2585			 */
2586			ss->go_s99_running = 1;
2587			fallthrough;	/* and start dma engine */
2588		case sdma_event_e10_go_hw_start:
2589			/* This reference means the state machine is started */
2590			sdma_get(&sde->state);
2591			sdma_set_state(sde,
2592				       sdma_state_s10_hw_start_up_halt_wait);
2593			break;
2594		case sdma_event_e15_hw_halt_done:
2595			break;
2596		case sdma_event_e25_hw_clean_up_done:
2597			break;
2598		case sdma_event_e40_sw_cleaned:
2599			sdma_sw_tear_down(sde);
2600			break;
2601		case sdma_event_e50_hw_cleaned:
2602			break;
2603		case sdma_event_e60_hw_halted:
2604			break;
2605		case sdma_event_e70_go_idle:
2606			break;
2607		case sdma_event_e80_hw_freeze:
2608			break;
2609		case sdma_event_e81_hw_frozen:
2610			break;
2611		case sdma_event_e82_hw_unfreeze:
2612			break;
2613		case sdma_event_e85_link_down:
2614			break;
2615		case sdma_event_e90_sw_halted:
2616			break;
2617		}
2618		break;
2619
2620	case sdma_state_s10_hw_start_up_halt_wait:
2621		switch (event) {
2622		case sdma_event_e00_go_hw_down:
2623			sdma_set_state(sde, sdma_state_s00_hw_down);
2624			sdma_sw_tear_down(sde);
2625			break;
2626		case sdma_event_e10_go_hw_start:
2627			break;
2628		case sdma_event_e15_hw_halt_done:
2629			sdma_set_state(sde,
2630				       sdma_state_s15_hw_start_up_clean_wait);
2631			sdma_start_hw_clean_up(sde);
2632			break;
2633		case sdma_event_e25_hw_clean_up_done:
2634			break;
2635		case sdma_event_e30_go_running:
2636			ss->go_s99_running = 1;
2637			break;
2638		case sdma_event_e40_sw_cleaned:
2639			break;
2640		case sdma_event_e50_hw_cleaned:
2641			break;
2642		case sdma_event_e60_hw_halted:
2643			schedule_work(&sde->err_halt_worker);
2644			break;
2645		case sdma_event_e70_go_idle:
2646			ss->go_s99_running = 0;
2647			break;
2648		case sdma_event_e80_hw_freeze:
2649			break;
2650		case sdma_event_e81_hw_frozen:
2651			break;
2652		case sdma_event_e82_hw_unfreeze:
2653			break;
2654		case sdma_event_e85_link_down:
2655			break;
2656		case sdma_event_e90_sw_halted:
2657			break;
2658		}
2659		break;
2660
2661	case sdma_state_s15_hw_start_up_clean_wait:
2662		switch (event) {
2663		case sdma_event_e00_go_hw_down:
2664			sdma_set_state(sde, sdma_state_s00_hw_down);
2665			sdma_sw_tear_down(sde);
2666			break;
2667		case sdma_event_e10_go_hw_start:
2668			break;
2669		case sdma_event_e15_hw_halt_done:
2670			break;
2671		case sdma_event_e25_hw_clean_up_done:
2672			sdma_hw_start_up(sde);
2673			sdma_set_state(sde, ss->go_s99_running ?
2674				       sdma_state_s99_running :
2675				       sdma_state_s20_idle);
2676			break;
2677		case sdma_event_e30_go_running:
2678			ss->go_s99_running = 1;
2679			break;
2680		case sdma_event_e40_sw_cleaned:
2681			break;
2682		case sdma_event_e50_hw_cleaned:
2683			break;
2684		case sdma_event_e60_hw_halted:
2685			break;
2686		case sdma_event_e70_go_idle:
2687			ss->go_s99_running = 0;
2688			break;
2689		case sdma_event_e80_hw_freeze:
2690			break;
2691		case sdma_event_e81_hw_frozen:
2692			break;
2693		case sdma_event_e82_hw_unfreeze:
2694			break;
2695		case sdma_event_e85_link_down:
2696			break;
2697		case sdma_event_e90_sw_halted:
2698			break;
2699		}
2700		break;
2701
2702	case sdma_state_s20_idle:
2703		switch (event) {
2704		case sdma_event_e00_go_hw_down:
2705			sdma_set_state(sde, sdma_state_s00_hw_down);
2706			sdma_sw_tear_down(sde);
2707			break;
2708		case sdma_event_e10_go_hw_start:
2709			break;
2710		case sdma_event_e15_hw_halt_done:
2711			break;
2712		case sdma_event_e25_hw_clean_up_done:
2713			break;
2714		case sdma_event_e30_go_running:
2715			sdma_set_state(sde, sdma_state_s99_running);
2716			ss->go_s99_running = 1;
2717			break;
2718		case sdma_event_e40_sw_cleaned:
2719			break;
2720		case sdma_event_e50_hw_cleaned:
2721			break;
2722		case sdma_event_e60_hw_halted:
2723			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
2724			schedule_work(&sde->err_halt_worker);
2725			break;
2726		case sdma_event_e70_go_idle:
2727			break;
2728		case sdma_event_e85_link_down:
2729		case sdma_event_e80_hw_freeze:
2730			sdma_set_state(sde, sdma_state_s80_hw_freeze);
2731			atomic_dec(&sde->dd->sdma_unfreeze_count);
2732			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2733			break;
2734		case sdma_event_e81_hw_frozen:
2735			break;
2736		case sdma_event_e82_hw_unfreeze:
2737			break;
2738		case sdma_event_e90_sw_halted:
2739			break;
2740		}
2741		break;
2742
2743	case sdma_state_s30_sw_clean_up_wait:
2744		switch (event) {
2745		case sdma_event_e00_go_hw_down:
2746			sdma_set_state(sde, sdma_state_s00_hw_down);
2747			break;
2748		case sdma_event_e10_go_hw_start:
2749			break;
2750		case sdma_event_e15_hw_halt_done:
2751			break;
2752		case sdma_event_e25_hw_clean_up_done:
2753			break;
2754		case sdma_event_e30_go_running:
2755			ss->go_s99_running = 1;
2756			break;
2757		case sdma_event_e40_sw_cleaned:
2758			sdma_set_state(sde, sdma_state_s40_hw_clean_up_wait);
2759			sdma_start_hw_clean_up(sde);
2760			break;
2761		case sdma_event_e50_hw_cleaned:
2762			break;
2763		case sdma_event_e60_hw_halted:
2764			break;
2765		case sdma_event_e70_go_idle:
2766			ss->go_s99_running = 0;
2767			break;
2768		case sdma_event_e80_hw_freeze:
2769			break;
2770		case sdma_event_e81_hw_frozen:
2771			break;
2772		case sdma_event_e82_hw_unfreeze:
2773			break;
2774		case sdma_event_e85_link_down:
2775			ss->go_s99_running = 0;
2776			break;
2777		case sdma_event_e90_sw_halted:
2778			break;
2779		}
2780		break;
2781
2782	case sdma_state_s40_hw_clean_up_wait:
2783		switch (event) {
2784		case sdma_event_e00_go_hw_down:
2785			sdma_set_state(sde, sdma_state_s00_hw_down);
2786			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2787			break;
2788		case sdma_event_e10_go_hw_start:
2789			break;
2790		case sdma_event_e15_hw_halt_done:
2791			break;
2792		case sdma_event_e25_hw_clean_up_done:
2793			sdma_hw_start_up(sde);
2794			sdma_set_state(sde, ss->go_s99_running ?
2795				       sdma_state_s99_running :
2796				       sdma_state_s20_idle);
2797			break;
2798		case sdma_event_e30_go_running:
2799			ss->go_s99_running = 1;
2800			break;
2801		case sdma_event_e40_sw_cleaned:
2802			break;
2803		case sdma_event_e50_hw_cleaned:
2804			break;
2805		case sdma_event_e60_hw_halted:
2806			break;
2807		case sdma_event_e70_go_idle:
2808			ss->go_s99_running = 0;
2809			break;
2810		case sdma_event_e80_hw_freeze:
2811			break;
2812		case sdma_event_e81_hw_frozen:
2813			break;
2814		case sdma_event_e82_hw_unfreeze:
2815			break;
2816		case sdma_event_e85_link_down:
2817			ss->go_s99_running = 0;
2818			break;
2819		case sdma_event_e90_sw_halted:
2820			break;
2821		}
2822		break;
2823
2824	case sdma_state_s50_hw_halt_wait:
2825		switch (event) {
2826		case sdma_event_e00_go_hw_down:
2827			sdma_set_state(sde, sdma_state_s00_hw_down);
2828			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2829			break;
2830		case sdma_event_e10_go_hw_start:
2831			break;
2832		case sdma_event_e15_hw_halt_done:
2833			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2834			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2835			break;
2836		case sdma_event_e25_hw_clean_up_done:
2837			break;
2838		case sdma_event_e30_go_running:
2839			ss->go_s99_running = 1;
2840			break;
2841		case sdma_event_e40_sw_cleaned:
2842			break;
2843		case sdma_event_e50_hw_cleaned:
2844			break;
2845		case sdma_event_e60_hw_halted:
2846			schedule_work(&sde->err_halt_worker);
2847			break;
2848		case sdma_event_e70_go_idle:
2849			ss->go_s99_running = 0;
2850			break;
2851		case sdma_event_e80_hw_freeze:
2852			break;
2853		case sdma_event_e81_hw_frozen:
2854			break;
2855		case sdma_event_e82_hw_unfreeze:
2856			break;
2857		case sdma_event_e85_link_down:
2858			ss->go_s99_running = 0;
2859			break;
2860		case sdma_event_e90_sw_halted:
2861			break;
2862		}
2863		break;
2864
2865	case sdma_state_s60_idle_halt_wait:
2866		switch (event) {
2867		case sdma_event_e00_go_hw_down:
2868			sdma_set_state(sde, sdma_state_s00_hw_down);
2869			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2870			break;
2871		case sdma_event_e10_go_hw_start:
2872			break;
2873		case sdma_event_e15_hw_halt_done:
2874			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2875			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2876			break;
2877		case sdma_event_e25_hw_clean_up_done:
2878			break;
2879		case sdma_event_e30_go_running:
2880			ss->go_s99_running = 1;
2881			break;
2882		case sdma_event_e40_sw_cleaned:
2883			break;
2884		case sdma_event_e50_hw_cleaned:
2885			break;
2886		case sdma_event_e60_hw_halted:
2887			schedule_work(&sde->err_halt_worker);
2888			break;
2889		case sdma_event_e70_go_idle:
2890			ss->go_s99_running = 0;
2891			break;
2892		case sdma_event_e80_hw_freeze:
2893			break;
2894		case sdma_event_e81_hw_frozen:
2895			break;
2896		case sdma_event_e82_hw_unfreeze:
2897			break;
2898		case sdma_event_e85_link_down:
2899			break;
2900		case sdma_event_e90_sw_halted:
2901			break;
2902		}
2903		break;
2904
2905	case sdma_state_s80_hw_freeze:
2906		switch (event) {
2907		case sdma_event_e00_go_hw_down:
2908			sdma_set_state(sde, sdma_state_s00_hw_down);
2909			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2910			break;
2911		case sdma_event_e10_go_hw_start:
2912			break;
2913		case sdma_event_e15_hw_halt_done:
2914			break;
2915		case sdma_event_e25_hw_clean_up_done:
2916			break;
2917		case sdma_event_e30_go_running:
2918			ss->go_s99_running = 1;
2919			break;
2920		case sdma_event_e40_sw_cleaned:
2921			break;
2922		case sdma_event_e50_hw_cleaned:
2923			break;
2924		case sdma_event_e60_hw_halted:
2925			break;
2926		case sdma_event_e70_go_idle:
2927			ss->go_s99_running = 0;
2928			break;
2929		case sdma_event_e80_hw_freeze:
2930			break;
2931		case sdma_event_e81_hw_frozen:
2932			sdma_set_state(sde, sdma_state_s82_freeze_sw_clean);
2933			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2934			break;
2935		case sdma_event_e82_hw_unfreeze:
2936			break;
2937		case sdma_event_e85_link_down:
2938			break;
2939		case sdma_event_e90_sw_halted:
2940			break;
2941		}
2942		break;
2943
2944	case sdma_state_s82_freeze_sw_clean:
2945		switch (event) {
2946		case sdma_event_e00_go_hw_down:
2947			sdma_set_state(sde, sdma_state_s00_hw_down);
2948			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2949			break;
2950		case sdma_event_e10_go_hw_start:
2951			break;
2952		case sdma_event_e15_hw_halt_done:
2953			break;
2954		case sdma_event_e25_hw_clean_up_done:
2955			break;
2956		case sdma_event_e30_go_running:
2957			ss->go_s99_running = 1;
2958			break;
2959		case sdma_event_e40_sw_cleaned:
2960			/* notify caller this engine is done cleaning */
2961			atomic_dec(&sde->dd->sdma_unfreeze_count);
2962			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2963			break;
2964		case sdma_event_e50_hw_cleaned:
2965			break;
2966		case sdma_event_e60_hw_halted:
2967			break;
2968		case sdma_event_e70_go_idle:
2969			ss->go_s99_running = 0;
2970			break;
2971		case sdma_event_e80_hw_freeze:
2972			break;
2973		case sdma_event_e81_hw_frozen:
2974			break;
2975		case sdma_event_e82_hw_unfreeze:
2976			sdma_hw_start_up(sde);
2977			sdma_set_state(sde, ss->go_s99_running ?
2978				       sdma_state_s99_running :
2979				       sdma_state_s20_idle);
2980			break;
2981		case sdma_event_e85_link_down:
2982			break;
2983		case sdma_event_e90_sw_halted:
2984			break;
2985		}
2986		break;
2987
2988	case sdma_state_s99_running:
2989		switch (event) {
2990		case sdma_event_e00_go_hw_down:
2991			sdma_set_state(sde, sdma_state_s00_hw_down);
2992			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2993			break;
2994		case sdma_event_e10_go_hw_start:
2995			break;
2996		case sdma_event_e15_hw_halt_done:
2997			break;
2998		case sdma_event_e25_hw_clean_up_done:
2999			break;
3000		case sdma_event_e30_go_running:
3001			break;
3002		case sdma_event_e40_sw_cleaned:
3003			break;
3004		case sdma_event_e50_hw_cleaned:
3005			break;
3006		case sdma_event_e60_hw_halted:
3007			need_progress = 1;
3008			sdma_err_progress_check_schedule(sde);
3009			fallthrough;
3010		case sdma_event_e90_sw_halted:
3011			/*
3012			* SW initiated halt does not perform engines
3013			* progress check
3014			*/
3015			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
3016			schedule_work(&sde->err_halt_worker);
3017			break;
3018		case sdma_event_e70_go_idle:
3019			sdma_set_state(sde, sdma_state_s60_idle_halt_wait);
3020			break;
3021		case sdma_event_e85_link_down:
3022			ss->go_s99_running = 0;
3023			fallthrough;
3024		case sdma_event_e80_hw_freeze:
3025			sdma_set_state(sde, sdma_state_s80_hw_freeze);
3026			atomic_dec(&sde->dd->sdma_unfreeze_count);
3027			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
3028			break;
3029		case sdma_event_e81_hw_frozen:
3030			break;
3031		case sdma_event_e82_hw_unfreeze:
3032			break;
3033		}
3034		break;
3035	}
3036
3037	ss->last_event = event;
3038	if (need_progress)
3039		sdma_make_progress(sde, 0);
3040}
3041
3042/*
3043 * _extend_sdma_tx_descs() - helper to extend txreq
3044 *
3045 * This is called once the initial nominal allocation
3046 * of descriptors in the sdma_txreq is exhausted.
3047 *
3048 * The code will bump the allocation up to the max
3049 * of MAX_DESC (64) descriptors. There doesn't seem
3050 * much point in an interim step. The last descriptor
3051 * is reserved for coalesce buffer in order to support
3052 * cases where input packet has >MAX_DESC iovecs.
3053 *
3054 */
3055static int _extend_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3056{
3057	int i;
3058	struct sdma_desc *descp;
3059
3060	/* Handle last descriptor */
3061	if (unlikely((tx->num_desc == (MAX_DESC - 1)))) {
3062		/* if tlen is 0, it is for padding, release last descriptor */
3063		if (!tx->tlen) {
3064			tx->desc_limit = MAX_DESC;
3065		} else if (!tx->coalesce_buf) {
3066			/* allocate coalesce buffer with space for padding */
3067			tx->coalesce_buf = kmalloc(tx->tlen + sizeof(u32),
3068						   GFP_ATOMIC);
3069			if (!tx->coalesce_buf)
3070				goto enomem;
3071			tx->coalesce_idx = 0;
3072		}
3073		return 0;
3074	}
3075
3076	if (unlikely(tx->num_desc == MAX_DESC))
3077		goto enomem;
3078
3079	descp = kmalloc_array(MAX_DESC, sizeof(struct sdma_desc), GFP_ATOMIC);
3080	if (!descp)
3081		goto enomem;
3082	tx->descp = descp;
3083
3084	/* reserve last descriptor for coalescing */
3085	tx->desc_limit = MAX_DESC - 1;
3086	/* copy ones already built */
3087	for (i = 0; i < tx->num_desc; i++)
3088		tx->descp[i] = tx->descs[i];
3089	return 0;
3090enomem:
3091	__sdma_txclean(dd, tx);
3092	return -ENOMEM;
3093}
3094
3095/*
3096 * ext_coal_sdma_tx_descs() - extend or coalesce sdma tx descriptors
3097 *
3098 * This is called once the initial nominal allocation of descriptors
3099 * in the sdma_txreq is exhausted.
3100 *
3101 * This function calls _extend_sdma_tx_descs to extend or allocate
3102 * coalesce buffer. If there is a allocated coalesce buffer, it will
3103 * copy the input packet data into the coalesce buffer. It also adds
3104 * coalesce buffer descriptor once when whole packet is received.
3105 *
3106 * Return:
3107 * <0 - error
3108 * 0 - coalescing, don't populate descriptor
3109 * 1 - continue with populating descriptor
3110 */
3111int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
3112			   int type, void *kvaddr, struct page *page,
3113			   unsigned long offset, u16 len)
3114{
3115	int pad_len, rval;
3116	dma_addr_t addr;
3117
3118	rval = _extend_sdma_tx_descs(dd, tx);
3119	if (rval) {
3120		__sdma_txclean(dd, tx);
3121		return rval;
3122	}
3123
3124	/* If coalesce buffer is allocated, copy data into it */
3125	if (tx->coalesce_buf) {
3126		if (type == SDMA_MAP_NONE) {
3127			__sdma_txclean(dd, tx);
3128			return -EINVAL;
3129		}
3130
3131		if (type == SDMA_MAP_PAGE) {
3132			kvaddr = kmap(page);
3133			kvaddr += offset;
3134		} else if (WARN_ON(!kvaddr)) {
3135			__sdma_txclean(dd, tx);
3136			return -EINVAL;
3137		}
3138
3139		memcpy(tx->coalesce_buf + tx->coalesce_idx, kvaddr, len);
3140		tx->coalesce_idx += len;
3141		if (type == SDMA_MAP_PAGE)
3142			kunmap(page);
3143
3144		/* If there is more data, return */
3145		if (tx->tlen - tx->coalesce_idx)
3146			return 0;
3147
3148		/* Whole packet is received; add any padding */
3149		pad_len = tx->packet_len & (sizeof(u32) - 1);
3150		if (pad_len) {
3151			pad_len = sizeof(u32) - pad_len;
3152			memset(tx->coalesce_buf + tx->coalesce_idx, 0, pad_len);
3153			/* padding is taken care of for coalescing case */
3154			tx->packet_len += pad_len;
3155			tx->tlen += pad_len;
3156		}
3157
3158		/* dma map the coalesce buffer */
3159		addr = dma_map_single(&dd->pcidev->dev,
3160				      tx->coalesce_buf,
3161				      tx->tlen,
3162				      DMA_TO_DEVICE);
3163
3164		if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
3165			__sdma_txclean(dd, tx);
3166			return -ENOSPC;
3167		}
3168
3169		/* Add descriptor for coalesce buffer */
3170		tx->desc_limit = MAX_DESC;
3171		return _sdma_txadd_daddr(dd, SDMA_MAP_SINGLE, tx,
3172					 addr, tx->tlen, NULL, NULL, NULL);
3173	}
3174
3175	return 1;
3176}
3177
3178/* Update sdes when the lmc changes */
3179void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid)
3180{
3181	struct sdma_engine *sde;
3182	int i;
3183	u64 sreg;
3184
3185	sreg = ((mask & SD(CHECK_SLID_MASK_MASK)) <<
3186		SD(CHECK_SLID_MASK_SHIFT)) |
3187		(((lid & mask) & SD(CHECK_SLID_VALUE_MASK)) <<
3188		SD(CHECK_SLID_VALUE_SHIFT));
3189
3190	for (i = 0; i < dd->num_sdma; i++) {
3191		hfi1_cdbg(LINKVERB, "SendDmaEngine[%d].SLID_CHECK = 0x%x",
3192			  i, (u32)sreg);
3193		sde = &dd->per_sdma[i];
3194		write_sde_csr(sde, SD(CHECK_SLID), sreg);
3195	}
3196}
3197
3198/* tx not dword sized - pad */
3199int _pad_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3200{
3201	int rval = 0;
3202
3203	if ((unlikely(tx->num_desc + 1 == tx->desc_limit))) {
3204		rval = _extend_sdma_tx_descs(dd, tx);
3205		if (rval) {
3206			__sdma_txclean(dd, tx);
3207			return rval;
3208		}
3209	}
3210
3211	/* finish the one just added */
3212	make_tx_sdma_desc(
3213		tx,
3214		SDMA_MAP_NONE,
3215		dd->sdma_pad_phys,
3216		sizeof(u32) - (tx->packet_len & (sizeof(u32) - 1)),
3217		NULL, NULL, NULL);
3218	tx->num_desc++;
3219	_sdma_close_tx(dd, tx);
3220	return rval;
3221}
3222
3223/*
3224 * Add ahg to the sdma_txreq
3225 *
3226 * The logic will consume up to 3
3227 * descriptors at the beginning of
3228 * sdma_txreq.
3229 */
3230void _sdma_txreq_ahgadd(
3231	struct sdma_txreq *tx,
3232	u8 num_ahg,
3233	u8 ahg_entry,
3234	u32 *ahg,
3235	u8 ahg_hlen)
3236{
3237	u32 i, shift = 0, desc = 0;
3238	u8 mode;
3239
3240	WARN_ON_ONCE(num_ahg > 9 || (ahg_hlen & 3) || ahg_hlen == 4);
3241	/* compute mode */
3242	if (num_ahg == 1)
3243		mode = SDMA_AHG_APPLY_UPDATE1;
3244	else if (num_ahg <= 5)
3245		mode = SDMA_AHG_APPLY_UPDATE2;
3246	else
3247		mode = SDMA_AHG_APPLY_UPDATE3;
3248	tx->num_desc++;
3249	/* initialize to consumed descriptors to zero */
3250	switch (mode) {
3251	case SDMA_AHG_APPLY_UPDATE3:
3252		tx->num_desc++;
3253		tx->descs[2].qw[0] = 0;
3254		tx->descs[2].qw[1] = 0;
3255		fallthrough;
3256	case SDMA_AHG_APPLY_UPDATE2:
3257		tx->num_desc++;
3258		tx->descs[1].qw[0] = 0;
3259		tx->descs[1].qw[1] = 0;
3260		break;
3261	}
3262	ahg_hlen >>= 2;
3263	tx->descs[0].qw[1] |=
3264		(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
3265			<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
3266		(((u64)ahg_hlen & SDMA_DESC1_HEADER_DWS_MASK)
3267			<< SDMA_DESC1_HEADER_DWS_SHIFT) |
3268		(((u64)mode & SDMA_DESC1_HEADER_MODE_MASK)
3269			<< SDMA_DESC1_HEADER_MODE_SHIFT) |
3270		(((u64)ahg[0] & SDMA_DESC1_HEADER_UPDATE1_MASK)
3271			<< SDMA_DESC1_HEADER_UPDATE1_SHIFT);
3272	for (i = 0; i < (num_ahg - 1); i++) {
3273		if (!shift && !(i & 2))
3274			desc++;
3275		tx->descs[desc].qw[!!(i & 2)] |=
3276			(((u64)ahg[i + 1])
3277				<< shift);
3278		shift = (shift + 32) & 63;
3279	}
3280}
3281
3282/**
3283 * sdma_ahg_alloc - allocate an AHG entry
3284 * @sde: engine to allocate from
3285 *
3286 * Return:
3287 * 0-31 when successful, -EOPNOTSUPP if AHG is not enabled,
3288 * -ENOSPC if an entry is not available
3289 */
3290int sdma_ahg_alloc(struct sdma_engine *sde)
3291{
3292	int nr;
3293	int oldbit;
3294
3295	if (!sde) {
3296		trace_hfi1_ahg_allocate(sde, -EINVAL);
3297		return -EINVAL;
3298	}
3299	while (1) {
3300		nr = ffz(READ_ONCE(sde->ahg_bits));
3301		if (nr > 31) {
3302			trace_hfi1_ahg_allocate(sde, -ENOSPC);
3303			return -ENOSPC;
3304		}
3305		oldbit = test_and_set_bit(nr, &sde->ahg_bits);
3306		if (!oldbit)
3307			break;
3308		cpu_relax();
3309	}
3310	trace_hfi1_ahg_allocate(sde, nr);
3311	return nr;
3312}
3313
3314/**
3315 * sdma_ahg_free - free an AHG entry
3316 * @sde: engine to return AHG entry
3317 * @ahg_index: index to free
3318 *
3319 * This routine frees the indicate AHG entry.
3320 */
3321void sdma_ahg_free(struct sdma_engine *sde, int ahg_index)
3322{
3323	if (!sde)
3324		return;
3325	trace_hfi1_ahg_deallocate(sde, ahg_index);
3326	if (ahg_index < 0 || ahg_index > 31)
3327		return;
3328	clear_bit(ahg_index, &sde->ahg_bits);
3329}
3330
3331/*
3332 * SPC freeze handling for SDMA engines.  Called when the driver knows
3333 * the SPC is going into a freeze but before the freeze is fully
3334 * settled.  Generally an error interrupt.
3335 *
3336 * This event will pull the engine out of running so no more entries can be
3337 * added to the engine's queue.
3338 */
3339void sdma_freeze_notify(struct hfi1_devdata *dd, int link_down)
3340{
3341	int i;
3342	enum sdma_events event = link_down ? sdma_event_e85_link_down :
3343					     sdma_event_e80_hw_freeze;
3344
3345	/* set up the wait but do not wait here */
3346	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3347
3348	/* tell all engines to stop running and wait */
3349	for (i = 0; i < dd->num_sdma; i++)
3350		sdma_process_event(&dd->per_sdma[i], event);
3351
3352	/* sdma_freeze() will wait for all engines to have stopped */
3353}
3354
3355/*
3356 * SPC freeze handling for SDMA engines.  Called when the driver knows
3357 * the SPC is fully frozen.
3358 */
3359void sdma_freeze(struct hfi1_devdata *dd)
3360{
3361	int i;
3362	int ret;
3363
3364	/*
3365	 * Make sure all engines have moved out of the running state before
3366	 * continuing.
3367	 */
3368	ret = wait_event_interruptible(dd->sdma_unfreeze_wq,
3369				       atomic_read(&dd->sdma_unfreeze_count) <=
3370				       0);
3371	/* interrupted or count is negative, then unloading - just exit */
3372	if (ret || atomic_read(&dd->sdma_unfreeze_count) < 0)
3373		return;
3374
3375	/* set up the count for the next wait */
3376	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3377
3378	/* tell all engines that the SPC is frozen, they can start cleaning */
3379	for (i = 0; i < dd->num_sdma; i++)
3380		sdma_process_event(&dd->per_sdma[i], sdma_event_e81_hw_frozen);
3381
3382	/*
3383	 * Wait for everyone to finish software clean before exiting.  The
3384	 * software clean will read engine CSRs, so must be completed before
3385	 * the next step, which will clear the engine CSRs.
3386	 */
3387	(void)wait_event_interruptible(dd->sdma_unfreeze_wq,
3388				atomic_read(&dd->sdma_unfreeze_count) <= 0);
3389	/* no need to check results - done no matter what */
3390}
3391
3392/*
3393 * SPC freeze handling for the SDMA engines.  Called after the SPC is unfrozen.
3394 *
3395 * The SPC freeze acts like a SDMA halt and a hardware clean combined.  All
3396 * that is left is a software clean.  We could do it after the SPC is fully
3397 * frozen, but then we'd have to add another state to wait for the unfreeze.
3398 * Instead, just defer the software clean until the unfreeze step.
3399 */
3400void sdma_unfreeze(struct hfi1_devdata *dd)
3401{
3402	int i;
3403
3404	/* tell all engines start freeze clean up */
3405	for (i = 0; i < dd->num_sdma; i++)
3406		sdma_process_event(&dd->per_sdma[i],
3407				   sdma_event_e82_hw_unfreeze);
3408}
3409
3410/**
3411 * _sdma_engine_progress_schedule() - schedule progress on engine
3412 * @sde: sdma_engine to schedule progress
3413 *
3414 */
3415void _sdma_engine_progress_schedule(
3416	struct sdma_engine *sde)
3417{
3418	trace_hfi1_sdma_engine_progress(sde, sde->progress_mask);
3419	/* assume we have selected a good cpu */
3420	write_csr(sde->dd,
3421		  CCE_INT_FORCE + (8 * (IS_SDMA_START / 64)),
3422		  sde->progress_mask);
3423}
3424