xref: /linux/drivers/infiniband/hw/hfi1/sdma.c (revision 55f3538c4923e9dfca132e99ebec370e8094afda)
1 /*
2  * Copyright(c) 2015, 2016 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 
69 static uint sdma_descq_cnt = SDMA_DESCQ_CNT;
70 module_param(sdma_descq_cnt, uint, S_IRUGO);
71 MODULE_PARM_DESC(sdma_descq_cnt, "Number of SDMA descq entries");
72 
73 static uint sdma_idle_cnt = 250;
74 module_param(sdma_idle_cnt, uint, S_IRUGO);
75 MODULE_PARM_DESC(sdma_idle_cnt, "sdma interrupt idle delay (ns,default 250)");
76 
77 uint mod_num_sdma;
78 module_param_named(num_sdma, mod_num_sdma, uint, S_IRUGO);
79 MODULE_PARM_DESC(num_sdma, "Set max number SDMA engines to use");
80 
81 static uint sdma_desct_intr = SDMA_DESC_INTR;
82 module_param_named(desct_intr, sdma_desct_intr, uint, S_IRUGO | S_IWUSR);
83 MODULE_PARM_DESC(desct_intr, "Number of SDMA descriptor before interrupt");
84 
85 #define SDMA_WAIT_BATCH_SIZE 20
86 /* max wait time for a SDMA engine to indicate it has halted */
87 #define SDMA_ERR_HALT_TIMEOUT 10 /* ms */
88 /* all SDMA engine errors that cause a halt */
89 
90 #define SD(name) SEND_DMA_##name
91 #define ALL_SDMA_ENG_HALT_ERRS \
92 	(SD(ENG_ERR_STATUS_SDMA_WRONG_DW_ERR_SMASK) \
93 	| SD(ENG_ERR_STATUS_SDMA_GEN_MISMATCH_ERR_SMASK) \
94 	| SD(ENG_ERR_STATUS_SDMA_TOO_LONG_ERR_SMASK) \
95 	| SD(ENG_ERR_STATUS_SDMA_TAIL_OUT_OF_BOUNDS_ERR_SMASK) \
96 	| SD(ENG_ERR_STATUS_SDMA_FIRST_DESC_ERR_SMASK) \
97 	| SD(ENG_ERR_STATUS_SDMA_MEM_READ_ERR_SMASK) \
98 	| SD(ENG_ERR_STATUS_SDMA_HALT_ERR_SMASK) \
99 	| SD(ENG_ERR_STATUS_SDMA_LENGTH_MISMATCH_ERR_SMASK) \
100 	| SD(ENG_ERR_STATUS_SDMA_PACKET_DESC_OVERFLOW_ERR_SMASK) \
101 	| SD(ENG_ERR_STATUS_SDMA_HEADER_SELECT_ERR_SMASK) \
102 	| SD(ENG_ERR_STATUS_SDMA_HEADER_ADDRESS_ERR_SMASK) \
103 	| SD(ENG_ERR_STATUS_SDMA_HEADER_LENGTH_ERR_SMASK) \
104 	| SD(ENG_ERR_STATUS_SDMA_TIMEOUT_ERR_SMASK) \
105 	| SD(ENG_ERR_STATUS_SDMA_DESC_TABLE_UNC_ERR_SMASK) \
106 	| SD(ENG_ERR_STATUS_SDMA_ASSEMBLY_UNC_ERR_SMASK) \
107 	| SD(ENG_ERR_STATUS_SDMA_PACKET_TRACKING_UNC_ERR_SMASK) \
108 	| SD(ENG_ERR_STATUS_SDMA_HEADER_STORAGE_UNC_ERR_SMASK) \
109 	| SD(ENG_ERR_STATUS_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_SMASK))
110 
111 /* sdma_sendctrl operations */
112 #define SDMA_SENDCTRL_OP_ENABLE    BIT(0)
113 #define SDMA_SENDCTRL_OP_INTENABLE BIT(1)
114 #define SDMA_SENDCTRL_OP_HALT      BIT(2)
115 #define SDMA_SENDCTRL_OP_CLEANUP   BIT(3)
116 
117 /* handle long defines */
118 #define SDMA_EGRESS_PACKET_OCCUPANCY_SMASK \
119 SEND_EGRESS_SEND_DMA_STATUS_SDMA_EGRESS_PACKET_OCCUPANCY_SMASK
120 #define SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT \
121 SEND_EGRESS_SEND_DMA_STATUS_SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT
122 
123 static const char * const sdma_state_names[] = {
124 	[sdma_state_s00_hw_down]                = "s00_HwDown",
125 	[sdma_state_s10_hw_start_up_halt_wait]  = "s10_HwStartUpHaltWait",
126 	[sdma_state_s15_hw_start_up_clean_wait] = "s15_HwStartUpCleanWait",
127 	[sdma_state_s20_idle]                   = "s20_Idle",
128 	[sdma_state_s30_sw_clean_up_wait]       = "s30_SwCleanUpWait",
129 	[sdma_state_s40_hw_clean_up_wait]       = "s40_HwCleanUpWait",
130 	[sdma_state_s50_hw_halt_wait]           = "s50_HwHaltWait",
131 	[sdma_state_s60_idle_halt_wait]         = "s60_IdleHaltWait",
132 	[sdma_state_s80_hw_freeze]		= "s80_HwFreeze",
133 	[sdma_state_s82_freeze_sw_clean]	= "s82_FreezeSwClean",
134 	[sdma_state_s99_running]                = "s99_Running",
135 };
136 
137 #ifdef CONFIG_SDMA_VERBOSITY
138 static const char * const sdma_event_names[] = {
139 	[sdma_event_e00_go_hw_down]   = "e00_GoHwDown",
140 	[sdma_event_e10_go_hw_start]  = "e10_GoHwStart",
141 	[sdma_event_e15_hw_halt_done] = "e15_HwHaltDone",
142 	[sdma_event_e25_hw_clean_up_done] = "e25_HwCleanUpDone",
143 	[sdma_event_e30_go_running]   = "e30_GoRunning",
144 	[sdma_event_e40_sw_cleaned]   = "e40_SwCleaned",
145 	[sdma_event_e50_hw_cleaned]   = "e50_HwCleaned",
146 	[sdma_event_e60_hw_halted]    = "e60_HwHalted",
147 	[sdma_event_e70_go_idle]      = "e70_GoIdle",
148 	[sdma_event_e80_hw_freeze]    = "e80_HwFreeze",
149 	[sdma_event_e81_hw_frozen]    = "e81_HwFrozen",
150 	[sdma_event_e82_hw_unfreeze]  = "e82_HwUnfreeze",
151 	[sdma_event_e85_link_down]    = "e85_LinkDown",
152 	[sdma_event_e90_sw_halted]    = "e90_SwHalted",
153 };
154 #endif
155 
156 static const struct sdma_set_state_action sdma_action_table[] = {
157 	[sdma_state_s00_hw_down] = {
158 		.go_s99_running_tofalse = 1,
159 		.op_enable = 0,
160 		.op_intenable = 0,
161 		.op_halt = 0,
162 		.op_cleanup = 0,
163 	},
164 	[sdma_state_s10_hw_start_up_halt_wait] = {
165 		.op_enable = 0,
166 		.op_intenable = 0,
167 		.op_halt = 1,
168 		.op_cleanup = 0,
169 	},
170 	[sdma_state_s15_hw_start_up_clean_wait] = {
171 		.op_enable = 0,
172 		.op_intenable = 1,
173 		.op_halt = 0,
174 		.op_cleanup = 1,
175 	},
176 	[sdma_state_s20_idle] = {
177 		.op_enable = 0,
178 		.op_intenable = 1,
179 		.op_halt = 0,
180 		.op_cleanup = 0,
181 	},
182 	[sdma_state_s30_sw_clean_up_wait] = {
183 		.op_enable = 0,
184 		.op_intenable = 0,
185 		.op_halt = 0,
186 		.op_cleanup = 0,
187 	},
188 	[sdma_state_s40_hw_clean_up_wait] = {
189 		.op_enable = 0,
190 		.op_intenable = 0,
191 		.op_halt = 0,
192 		.op_cleanup = 1,
193 	},
194 	[sdma_state_s50_hw_halt_wait] = {
195 		.op_enable = 0,
196 		.op_intenable = 0,
197 		.op_halt = 0,
198 		.op_cleanup = 0,
199 	},
200 	[sdma_state_s60_idle_halt_wait] = {
201 		.go_s99_running_tofalse = 1,
202 		.op_enable = 0,
203 		.op_intenable = 0,
204 		.op_halt = 1,
205 		.op_cleanup = 0,
206 	},
207 	[sdma_state_s80_hw_freeze] = {
208 		.op_enable = 0,
209 		.op_intenable = 0,
210 		.op_halt = 0,
211 		.op_cleanup = 0,
212 	},
213 	[sdma_state_s82_freeze_sw_clean] = {
214 		.op_enable = 0,
215 		.op_intenable = 0,
216 		.op_halt = 0,
217 		.op_cleanup = 0,
218 	},
219 	[sdma_state_s99_running] = {
220 		.op_enable = 1,
221 		.op_intenable = 1,
222 		.op_halt = 0,
223 		.op_cleanup = 0,
224 		.go_s99_running_totrue = 1,
225 	},
226 };
227 
228 #define SDMA_TAIL_UPDATE_THRESH 0x1F
229 
230 /* declare all statics here rather than keep sorting */
231 static void sdma_complete(struct kref *);
232 static void sdma_finalput(struct sdma_state *);
233 static void sdma_get(struct sdma_state *);
234 static void sdma_hw_clean_up_task(unsigned long);
235 static void sdma_put(struct sdma_state *);
236 static void sdma_set_state(struct sdma_engine *, enum sdma_states);
237 static void sdma_start_hw_clean_up(struct sdma_engine *);
238 static void sdma_sw_clean_up_task(unsigned long);
239 static void sdma_sendctrl(struct sdma_engine *, unsigned);
240 static void init_sdma_regs(struct sdma_engine *, u32, uint);
241 static void sdma_process_event(
242 	struct sdma_engine *sde,
243 	enum sdma_events event);
244 static void __sdma_process_event(
245 	struct sdma_engine *sde,
246 	enum sdma_events event);
247 static void dump_sdma_state(struct sdma_engine *sde);
248 static void sdma_make_progress(struct sdma_engine *sde, u64 status);
249 static void sdma_desc_avail(struct sdma_engine *sde, uint avail);
250 static void sdma_flush_descq(struct sdma_engine *sde);
251 
252 /**
253  * sdma_state_name() - return state string from enum
254  * @state: state
255  */
256 static const char *sdma_state_name(enum sdma_states state)
257 {
258 	return sdma_state_names[state];
259 }
260 
261 static void sdma_get(struct sdma_state *ss)
262 {
263 	kref_get(&ss->kref);
264 }
265 
266 static void sdma_complete(struct kref *kref)
267 {
268 	struct sdma_state *ss =
269 		container_of(kref, struct sdma_state, kref);
270 
271 	complete(&ss->comp);
272 }
273 
274 static void sdma_put(struct sdma_state *ss)
275 {
276 	kref_put(&ss->kref, sdma_complete);
277 }
278 
279 static void sdma_finalput(struct sdma_state *ss)
280 {
281 	sdma_put(ss);
282 	wait_for_completion(&ss->comp);
283 }
284 
285 static inline void write_sde_csr(
286 	struct sdma_engine *sde,
287 	u32 offset0,
288 	u64 value)
289 {
290 	write_kctxt_csr(sde->dd, sde->this_idx, offset0, value);
291 }
292 
293 static inline u64 read_sde_csr(
294 	struct sdma_engine *sde,
295 	u32 offset0)
296 {
297 	return read_kctxt_csr(sde->dd, sde->this_idx, offset0);
298 }
299 
300 /*
301  * sdma_wait_for_packet_egress() - wait for the VL FIFO occupancy for
302  * sdma engine 'sde' to drop to 0.
303  */
304 static void sdma_wait_for_packet_egress(struct sdma_engine *sde,
305 					int pause)
306 {
307 	u64 off = 8 * sde->this_idx;
308 	struct hfi1_devdata *dd = sde->dd;
309 	int lcnt = 0;
310 	u64 reg_prev;
311 	u64 reg = 0;
312 
313 	while (1) {
314 		reg_prev = reg;
315 		reg = read_csr(dd, off + SEND_EGRESS_SEND_DMA_STATUS);
316 
317 		reg &= SDMA_EGRESS_PACKET_OCCUPANCY_SMASK;
318 		reg >>= SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT;
319 		if (reg == 0)
320 			break;
321 		/* counter is reest if accupancy count changes */
322 		if (reg != reg_prev)
323 			lcnt = 0;
324 		if (lcnt++ > 500) {
325 			/* timed out - bounce the link */
326 			dd_dev_err(dd, "%s: engine %u timeout waiting for packets to egress, remaining count %u, bouncing link\n",
327 				   __func__, sde->this_idx, (u32)reg);
328 			queue_work(dd->pport->link_wq,
329 				   &dd->pport->link_bounce_work);
330 			break;
331 		}
332 		udelay(1);
333 	}
334 }
335 
336 /*
337  * sdma_wait() - wait for packet egress to complete for all SDMA engines,
338  * and pause for credit return.
339  */
340 void sdma_wait(struct hfi1_devdata *dd)
341 {
342 	int i;
343 
344 	for (i = 0; i < dd->num_sdma; i++) {
345 		struct sdma_engine *sde = &dd->per_sdma[i];
346 
347 		sdma_wait_for_packet_egress(sde, 0);
348 	}
349 }
350 
351 static inline void sdma_set_desc_cnt(struct sdma_engine *sde, unsigned cnt)
352 {
353 	u64 reg;
354 
355 	if (!(sde->dd->flags & HFI1_HAS_SDMA_TIMEOUT))
356 		return;
357 	reg = cnt;
358 	reg &= SD(DESC_CNT_CNT_MASK);
359 	reg <<= SD(DESC_CNT_CNT_SHIFT);
360 	write_sde_csr(sde, SD(DESC_CNT), reg);
361 }
362 
363 static inline void complete_tx(struct sdma_engine *sde,
364 			       struct sdma_txreq *tx,
365 			       int res)
366 {
367 	/* protect against complete modifying */
368 	struct iowait *wait = tx->wait;
369 	callback_t complete = tx->complete;
370 
371 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
372 	trace_hfi1_sdma_out_sn(sde, tx->sn);
373 	if (WARN_ON_ONCE(sde->head_sn != tx->sn))
374 		dd_dev_err(sde->dd, "expected %llu got %llu\n",
375 			   sde->head_sn, tx->sn);
376 	sde->head_sn++;
377 #endif
378 	__sdma_txclean(sde->dd, tx);
379 	if (complete)
380 		(*complete)(tx, res);
381 	if (wait && iowait_sdma_dec(wait))
382 		iowait_drain_wakeup(wait);
383 }
384 
385 /*
386  * Complete all the sdma requests with a SDMA_TXREQ_S_ABORTED status
387  *
388  * Depending on timing there can be txreqs in two places:
389  * - in the descq ring
390  * - in the flush list
391  *
392  * To avoid ordering issues the descq ring needs to be flushed
393  * first followed by the flush list.
394  *
395  * This routine is called from two places
396  * - From a work queue item
397  * - Directly from the state machine just before setting the
398  *   state to running
399  *
400  * Must be called with head_lock held
401  *
402  */
403 static void sdma_flush(struct sdma_engine *sde)
404 {
405 	struct sdma_txreq *txp, *txp_next;
406 	LIST_HEAD(flushlist);
407 	unsigned long flags;
408 
409 	/* flush from head to tail */
410 	sdma_flush_descq(sde);
411 	spin_lock_irqsave(&sde->flushlist_lock, flags);
412 	/* copy flush list */
413 	list_for_each_entry_safe(txp, txp_next, &sde->flushlist, list) {
414 		list_del_init(&txp->list);
415 		list_add_tail(&txp->list, &flushlist);
416 	}
417 	spin_unlock_irqrestore(&sde->flushlist_lock, flags);
418 	/* flush from flush list */
419 	list_for_each_entry_safe(txp, txp_next, &flushlist, list)
420 		complete_tx(sde, txp, SDMA_TXREQ_S_ABORTED);
421 }
422 
423 /*
424  * Fields a work request for flushing the descq ring
425  * and the flush list
426  *
427  * If the engine has been brought to running during
428  * the scheduling delay, the flush is ignored, assuming
429  * that the process of bringing the engine to running
430  * would have done this flush prior to going to running.
431  *
432  */
433 static void sdma_field_flush(struct work_struct *work)
434 {
435 	unsigned long flags;
436 	struct sdma_engine *sde =
437 		container_of(work, struct sdma_engine, flush_worker);
438 
439 	write_seqlock_irqsave(&sde->head_lock, flags);
440 	if (!__sdma_running(sde))
441 		sdma_flush(sde);
442 	write_sequnlock_irqrestore(&sde->head_lock, flags);
443 }
444 
445 static void sdma_err_halt_wait(struct work_struct *work)
446 {
447 	struct sdma_engine *sde = container_of(work, struct sdma_engine,
448 						err_halt_worker);
449 	u64 statuscsr;
450 	unsigned long timeout;
451 
452 	timeout = jiffies + msecs_to_jiffies(SDMA_ERR_HALT_TIMEOUT);
453 	while (1) {
454 		statuscsr = read_sde_csr(sde, SD(STATUS));
455 		statuscsr &= SD(STATUS_ENG_HALTED_SMASK);
456 		if (statuscsr)
457 			break;
458 		if (time_after(jiffies, timeout)) {
459 			dd_dev_err(sde->dd,
460 				   "SDMA engine %d - timeout waiting for engine to halt\n",
461 				   sde->this_idx);
462 			/*
463 			 * Continue anyway.  This could happen if there was
464 			 * an uncorrectable error in the wrong spot.
465 			 */
466 			break;
467 		}
468 		usleep_range(80, 120);
469 	}
470 
471 	sdma_process_event(sde, sdma_event_e15_hw_halt_done);
472 }
473 
474 static void sdma_err_progress_check_schedule(struct sdma_engine *sde)
475 {
476 	if (!is_bx(sde->dd) && HFI1_CAP_IS_KSET(SDMA_AHG)) {
477 		unsigned index;
478 		struct hfi1_devdata *dd = sde->dd;
479 
480 		for (index = 0; index < dd->num_sdma; index++) {
481 			struct sdma_engine *curr_sdma = &dd->per_sdma[index];
482 
483 			if (curr_sdma != sde)
484 				curr_sdma->progress_check_head =
485 							curr_sdma->descq_head;
486 		}
487 		dd_dev_err(sde->dd,
488 			   "SDMA engine %d - check scheduled\n",
489 				sde->this_idx);
490 		mod_timer(&sde->err_progress_check_timer, jiffies + 10);
491 	}
492 }
493 
494 static void sdma_err_progress_check(struct timer_list *t)
495 {
496 	unsigned index;
497 	struct sdma_engine *sde = from_timer(sde, t, err_progress_check_timer);
498 
499 	dd_dev_err(sde->dd, "SDE progress check event\n");
500 	for (index = 0; index < sde->dd->num_sdma; index++) {
501 		struct sdma_engine *curr_sde = &sde->dd->per_sdma[index];
502 		unsigned long flags;
503 
504 		/* check progress on each engine except the current one */
505 		if (curr_sde == sde)
506 			continue;
507 		/*
508 		 * We must lock interrupts when acquiring sde->lock,
509 		 * to avoid a deadlock if interrupt triggers and spins on
510 		 * the same lock on same CPU
511 		 */
512 		spin_lock_irqsave(&curr_sde->tail_lock, flags);
513 		write_seqlock(&curr_sde->head_lock);
514 
515 		/* skip non-running queues */
516 		if (curr_sde->state.current_state != sdma_state_s99_running) {
517 			write_sequnlock(&curr_sde->head_lock);
518 			spin_unlock_irqrestore(&curr_sde->tail_lock, flags);
519 			continue;
520 		}
521 
522 		if ((curr_sde->descq_head != curr_sde->descq_tail) &&
523 		    (curr_sde->descq_head ==
524 				curr_sde->progress_check_head))
525 			__sdma_process_event(curr_sde,
526 					     sdma_event_e90_sw_halted);
527 		write_sequnlock(&curr_sde->head_lock);
528 		spin_unlock_irqrestore(&curr_sde->tail_lock, flags);
529 	}
530 	schedule_work(&sde->err_halt_worker);
531 }
532 
533 static void sdma_hw_clean_up_task(unsigned long opaque)
534 {
535 	struct sdma_engine *sde = (struct sdma_engine *)opaque;
536 	u64 statuscsr;
537 
538 	while (1) {
539 #ifdef CONFIG_SDMA_VERBOSITY
540 		dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
541 			   sde->this_idx, slashstrip(__FILE__), __LINE__,
542 			__func__);
543 #endif
544 		statuscsr = read_sde_csr(sde, SD(STATUS));
545 		statuscsr &= SD(STATUS_ENG_CLEANED_UP_SMASK);
546 		if (statuscsr)
547 			break;
548 		udelay(10);
549 	}
550 
551 	sdma_process_event(sde, sdma_event_e25_hw_clean_up_done);
552 }
553 
554 static inline struct sdma_txreq *get_txhead(struct sdma_engine *sde)
555 {
556 	return sde->tx_ring[sde->tx_head & sde->sdma_mask];
557 }
558 
559 /*
560  * flush ring for recovery
561  */
562 static void sdma_flush_descq(struct sdma_engine *sde)
563 {
564 	u16 head, tail;
565 	int progress = 0;
566 	struct sdma_txreq *txp = get_txhead(sde);
567 
568 	/* The reason for some of the complexity of this code is that
569 	 * not all descriptors have corresponding txps.  So, we have to
570 	 * be able to skip over descs until we wander into the range of
571 	 * the next txp on the list.
572 	 */
573 	head = sde->descq_head & sde->sdma_mask;
574 	tail = sde->descq_tail & sde->sdma_mask;
575 	while (head != tail) {
576 		/* advance head, wrap if needed */
577 		head = ++sde->descq_head & sde->sdma_mask;
578 		/* if now past this txp's descs, do the callback */
579 		if (txp && txp->next_descq_idx == head) {
580 			/* remove from list */
581 			sde->tx_ring[sde->tx_head++ & sde->sdma_mask] = NULL;
582 			complete_tx(sde, txp, SDMA_TXREQ_S_ABORTED);
583 			trace_hfi1_sdma_progress(sde, head, tail, txp);
584 			txp = get_txhead(sde);
585 		}
586 		progress++;
587 	}
588 	if (progress)
589 		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
590 }
591 
592 static void sdma_sw_clean_up_task(unsigned long opaque)
593 {
594 	struct sdma_engine *sde = (struct sdma_engine *)opaque;
595 	unsigned long flags;
596 
597 	spin_lock_irqsave(&sde->tail_lock, flags);
598 	write_seqlock(&sde->head_lock);
599 
600 	/*
601 	 * At this point, the following should always be true:
602 	 * - We are halted, so no more descriptors are getting retired.
603 	 * - We are not running, so no one is submitting new work.
604 	 * - Only we can send the e40_sw_cleaned, so we can't start
605 	 *   running again until we say so.  So, the active list and
606 	 *   descq are ours to play with.
607 	 */
608 
609 	/*
610 	 * In the error clean up sequence, software clean must be called
611 	 * before the hardware clean so we can use the hardware head in
612 	 * the progress routine.  A hardware clean or SPC unfreeze will
613 	 * reset the hardware head.
614 	 *
615 	 * Process all retired requests. The progress routine will use the
616 	 * latest physical hardware head - we are not running so speed does
617 	 * not matter.
618 	 */
619 	sdma_make_progress(sde, 0);
620 
621 	sdma_flush(sde);
622 
623 	/*
624 	 * Reset our notion of head and tail.
625 	 * Note that the HW registers have been reset via an earlier
626 	 * clean up.
627 	 */
628 	sde->descq_tail = 0;
629 	sde->descq_head = 0;
630 	sde->desc_avail = sdma_descq_freecnt(sde);
631 	*sde->head_dma = 0;
632 
633 	__sdma_process_event(sde, sdma_event_e40_sw_cleaned);
634 
635 	write_sequnlock(&sde->head_lock);
636 	spin_unlock_irqrestore(&sde->tail_lock, flags);
637 }
638 
639 static void sdma_sw_tear_down(struct sdma_engine *sde)
640 {
641 	struct sdma_state *ss = &sde->state;
642 
643 	/* Releasing this reference means the state machine has stopped. */
644 	sdma_put(ss);
645 
646 	/* stop waiting for all unfreeze events to complete */
647 	atomic_set(&sde->dd->sdma_unfreeze_count, -1);
648 	wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
649 }
650 
651 static void sdma_start_hw_clean_up(struct sdma_engine *sde)
652 {
653 	tasklet_hi_schedule(&sde->sdma_hw_clean_up_task);
654 }
655 
656 static void sdma_set_state(struct sdma_engine *sde,
657 			   enum sdma_states next_state)
658 {
659 	struct sdma_state *ss = &sde->state;
660 	const struct sdma_set_state_action *action = sdma_action_table;
661 	unsigned op = 0;
662 
663 	trace_hfi1_sdma_state(
664 		sde,
665 		sdma_state_names[ss->current_state],
666 		sdma_state_names[next_state]);
667 
668 	/* debugging bookkeeping */
669 	ss->previous_state = ss->current_state;
670 	ss->previous_op = ss->current_op;
671 	ss->current_state = next_state;
672 
673 	if (ss->previous_state != sdma_state_s99_running &&
674 	    next_state == sdma_state_s99_running)
675 		sdma_flush(sde);
676 
677 	if (action[next_state].op_enable)
678 		op |= SDMA_SENDCTRL_OP_ENABLE;
679 
680 	if (action[next_state].op_intenable)
681 		op |= SDMA_SENDCTRL_OP_INTENABLE;
682 
683 	if (action[next_state].op_halt)
684 		op |= SDMA_SENDCTRL_OP_HALT;
685 
686 	if (action[next_state].op_cleanup)
687 		op |= SDMA_SENDCTRL_OP_CLEANUP;
688 
689 	if (action[next_state].go_s99_running_tofalse)
690 		ss->go_s99_running = 0;
691 
692 	if (action[next_state].go_s99_running_totrue)
693 		ss->go_s99_running = 1;
694 
695 	ss->current_op = op;
696 	sdma_sendctrl(sde, ss->current_op);
697 }
698 
699 /**
700  * sdma_get_descq_cnt() - called when device probed
701  *
702  * Return a validated descq count.
703  *
704  * This is currently only used in the verbs initialization to build the tx
705  * list.
706  *
707  * This will probably be deleted in favor of a more scalable approach to
708  * alloc tx's.
709  *
710  */
711 u16 sdma_get_descq_cnt(void)
712 {
713 	u16 count = sdma_descq_cnt;
714 
715 	if (!count)
716 		return SDMA_DESCQ_CNT;
717 	/* count must be a power of 2 greater than 64 and less than
718 	 * 32768.   Otherwise return default.
719 	 */
720 	if (!is_power_of_2(count))
721 		return SDMA_DESCQ_CNT;
722 	if (count < 64 || count > 32768)
723 		return SDMA_DESCQ_CNT;
724 	return count;
725 }
726 
727 /**
728  * sdma_engine_get_vl() - return vl for a given sdma engine
729  * @sde: sdma engine
730  *
731  * This function returns the vl mapped to a given engine, or an error if
732  * the mapping can't be found. The mapping fields are protected by RCU.
733  */
734 int sdma_engine_get_vl(struct sdma_engine *sde)
735 {
736 	struct hfi1_devdata *dd = sde->dd;
737 	struct sdma_vl_map *m;
738 	u8 vl;
739 
740 	if (sde->this_idx >= TXE_NUM_SDMA_ENGINES)
741 		return -EINVAL;
742 
743 	rcu_read_lock();
744 	m = rcu_dereference(dd->sdma_map);
745 	if (unlikely(!m)) {
746 		rcu_read_unlock();
747 		return -EINVAL;
748 	}
749 	vl = m->engine_to_vl[sde->this_idx];
750 	rcu_read_unlock();
751 
752 	return vl;
753 }
754 
755 /**
756  * sdma_select_engine_vl() - select sdma engine
757  * @dd: devdata
758  * @selector: a spreading factor
759  * @vl: this vl
760  *
761  *
762  * This function returns an engine based on the selector and a vl.  The
763  * mapping fields are protected by RCU.
764  */
765 struct sdma_engine *sdma_select_engine_vl(
766 	struct hfi1_devdata *dd,
767 	u32 selector,
768 	u8 vl)
769 {
770 	struct sdma_vl_map *m;
771 	struct sdma_map_elem *e;
772 	struct sdma_engine *rval;
773 
774 	/* NOTE This should only happen if SC->VL changed after the initial
775 	 *      checks on the QP/AH
776 	 *      Default will return engine 0 below
777 	 */
778 	if (vl >= num_vls) {
779 		rval = NULL;
780 		goto done;
781 	}
782 
783 	rcu_read_lock();
784 	m = rcu_dereference(dd->sdma_map);
785 	if (unlikely(!m)) {
786 		rcu_read_unlock();
787 		return &dd->per_sdma[0];
788 	}
789 	e = m->map[vl & m->mask];
790 	rval = e->sde[selector & e->mask];
791 	rcu_read_unlock();
792 
793 done:
794 	rval =  !rval ? &dd->per_sdma[0] : rval;
795 	trace_hfi1_sdma_engine_select(dd, selector, vl, rval->this_idx);
796 	return rval;
797 }
798 
799 /**
800  * sdma_select_engine_sc() - select sdma engine
801  * @dd: devdata
802  * @selector: a spreading factor
803  * @sc5: the 5 bit sc
804  *
805  *
806  * This function returns an engine based on the selector and an sc.
807  */
808 struct sdma_engine *sdma_select_engine_sc(
809 	struct hfi1_devdata *dd,
810 	u32 selector,
811 	u8 sc5)
812 {
813 	u8 vl = sc_to_vlt(dd, sc5);
814 
815 	return sdma_select_engine_vl(dd, selector, vl);
816 }
817 
818 struct sdma_rht_map_elem {
819 	u32 mask;
820 	u8 ctr;
821 	struct sdma_engine *sde[0];
822 };
823 
824 struct sdma_rht_node {
825 	unsigned long cpu_id;
826 	struct sdma_rht_map_elem *map[HFI1_MAX_VLS_SUPPORTED];
827 	struct rhash_head node;
828 };
829 
830 #define NR_CPUS_HINT 192
831 
832 static const struct rhashtable_params sdma_rht_params = {
833 	.nelem_hint = NR_CPUS_HINT,
834 	.head_offset = offsetof(struct sdma_rht_node, node),
835 	.key_offset = offsetof(struct sdma_rht_node, cpu_id),
836 	.key_len = FIELD_SIZEOF(struct sdma_rht_node, cpu_id),
837 	.max_size = NR_CPUS,
838 	.min_size = 8,
839 	.automatic_shrinking = true,
840 };
841 
842 /*
843  * sdma_select_user_engine() - select sdma engine based on user setup
844  * @dd: devdata
845  * @selector: a spreading factor
846  * @vl: this vl
847  *
848  * This function returns an sdma engine for a user sdma request.
849  * User defined sdma engine affinity setting is honored when applicable,
850  * otherwise system default sdma engine mapping is used. To ensure correct
851  * ordering, the mapping from <selector, vl> to sde must remain unchanged.
852  */
853 struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd,
854 					    u32 selector, u8 vl)
855 {
856 	struct sdma_rht_node *rht_node;
857 	struct sdma_engine *sde = NULL;
858 	const struct cpumask *current_mask = &current->cpus_allowed;
859 	unsigned long cpu_id;
860 
861 	/*
862 	 * To ensure that always the same sdma engine(s) will be
863 	 * selected make sure the process is pinned to this CPU only.
864 	 */
865 	if (cpumask_weight(current_mask) != 1)
866 		goto out;
867 
868 	cpu_id = smp_processor_id();
869 	rcu_read_lock();
870 	rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu_id,
871 					  sdma_rht_params);
872 
873 	if (rht_node && rht_node->map[vl]) {
874 		struct sdma_rht_map_elem *map = rht_node->map[vl];
875 
876 		sde = map->sde[selector & map->mask];
877 	}
878 	rcu_read_unlock();
879 
880 	if (sde)
881 		return sde;
882 
883 out:
884 	return sdma_select_engine_vl(dd, selector, vl);
885 }
886 
887 static void sdma_populate_sde_map(struct sdma_rht_map_elem *map)
888 {
889 	int i;
890 
891 	for (i = 0; i < roundup_pow_of_two(map->ctr ? : 1) - map->ctr; i++)
892 		map->sde[map->ctr + i] = map->sde[i];
893 }
894 
895 static void sdma_cleanup_sde_map(struct sdma_rht_map_elem *map,
896 				 struct sdma_engine *sde)
897 {
898 	unsigned int i, pow;
899 
900 	/* only need to check the first ctr entries for a match */
901 	for (i = 0; i < map->ctr; i++) {
902 		if (map->sde[i] == sde) {
903 			memmove(&map->sde[i], &map->sde[i + 1],
904 				(map->ctr - i - 1) * sizeof(map->sde[0]));
905 			map->ctr--;
906 			pow = roundup_pow_of_two(map->ctr ? : 1);
907 			map->mask = pow - 1;
908 			sdma_populate_sde_map(map);
909 			break;
910 		}
911 	}
912 }
913 
914 /*
915  * Prevents concurrent reads and writes of the sdma engine cpu_mask
916  */
917 static DEFINE_MUTEX(process_to_sde_mutex);
918 
919 ssize_t sdma_set_cpu_to_sde_map(struct sdma_engine *sde, const char *buf,
920 				size_t count)
921 {
922 	struct hfi1_devdata *dd = sde->dd;
923 	cpumask_var_t mask, new_mask;
924 	unsigned long cpu;
925 	int ret, vl, sz;
926 
927 	vl = sdma_engine_get_vl(sde);
928 	if (unlikely(vl < 0))
929 		return -EINVAL;
930 
931 	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
932 	if (!ret)
933 		return -ENOMEM;
934 
935 	ret = zalloc_cpumask_var(&new_mask, GFP_KERNEL);
936 	if (!ret) {
937 		free_cpumask_var(mask);
938 		return -ENOMEM;
939 	}
940 	ret = cpulist_parse(buf, mask);
941 	if (ret)
942 		goto out_free;
943 
944 	if (!cpumask_subset(mask, cpu_online_mask)) {
945 		dd_dev_warn(sde->dd, "Invalid CPU mask\n");
946 		ret = -EINVAL;
947 		goto out_free;
948 	}
949 
950 	sz = sizeof(struct sdma_rht_map_elem) +
951 			(TXE_NUM_SDMA_ENGINES * sizeof(struct sdma_engine *));
952 
953 	mutex_lock(&process_to_sde_mutex);
954 
955 	for_each_cpu(cpu, mask) {
956 		struct sdma_rht_node *rht_node;
957 
958 		/* Check if we have this already mapped */
959 		if (cpumask_test_cpu(cpu, &sde->cpu_mask)) {
960 			cpumask_set_cpu(cpu, new_mask);
961 			continue;
962 		}
963 
964 		if (vl >= ARRAY_SIZE(rht_node->map)) {
965 			ret = -EINVAL;
966 			goto out;
967 		}
968 
969 		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
970 						  sdma_rht_params);
971 		if (!rht_node) {
972 			rht_node = kzalloc(sizeof(*rht_node), GFP_KERNEL);
973 			if (!rht_node) {
974 				ret = -ENOMEM;
975 				goto out;
976 			}
977 
978 			rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
979 			if (!rht_node->map[vl]) {
980 				kfree(rht_node);
981 				ret = -ENOMEM;
982 				goto out;
983 			}
984 			rht_node->cpu_id = cpu;
985 			rht_node->map[vl]->mask = 0;
986 			rht_node->map[vl]->ctr = 1;
987 			rht_node->map[vl]->sde[0] = sde;
988 
989 			ret = rhashtable_insert_fast(dd->sdma_rht,
990 						     &rht_node->node,
991 						     sdma_rht_params);
992 			if (ret) {
993 				kfree(rht_node->map[vl]);
994 				kfree(rht_node);
995 				dd_dev_err(sde->dd, "Failed to set process to sde affinity for cpu %lu\n",
996 					   cpu);
997 				goto out;
998 			}
999 
1000 		} else {
1001 			int ctr, pow;
1002 
1003 			/* Add new user mappings */
1004 			if (!rht_node->map[vl])
1005 				rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
1006 
1007 			if (!rht_node->map[vl]) {
1008 				ret = -ENOMEM;
1009 				goto out;
1010 			}
1011 
1012 			rht_node->map[vl]->ctr++;
1013 			ctr = rht_node->map[vl]->ctr;
1014 			rht_node->map[vl]->sde[ctr - 1] = sde;
1015 			pow = roundup_pow_of_two(ctr);
1016 			rht_node->map[vl]->mask = pow - 1;
1017 
1018 			/* Populate the sde map table */
1019 			sdma_populate_sde_map(rht_node->map[vl]);
1020 		}
1021 		cpumask_set_cpu(cpu, new_mask);
1022 	}
1023 
1024 	/* Clean up old mappings */
1025 	for_each_cpu(cpu, cpu_online_mask) {
1026 		struct sdma_rht_node *rht_node;
1027 
1028 		/* Don't cleanup sdes that are set in the new mask */
1029 		if (cpumask_test_cpu(cpu, mask))
1030 			continue;
1031 
1032 		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
1033 						  sdma_rht_params);
1034 		if (rht_node) {
1035 			bool empty = true;
1036 			int i;
1037 
1038 			/* Remove mappings for old sde */
1039 			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1040 				if (rht_node->map[i])
1041 					sdma_cleanup_sde_map(rht_node->map[i],
1042 							     sde);
1043 
1044 			/* Free empty hash table entries */
1045 			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1046 				if (!rht_node->map[i])
1047 					continue;
1048 
1049 				if (rht_node->map[i]->ctr) {
1050 					empty = false;
1051 					break;
1052 				}
1053 			}
1054 
1055 			if (empty) {
1056 				ret = rhashtable_remove_fast(dd->sdma_rht,
1057 							     &rht_node->node,
1058 							     sdma_rht_params);
1059 				WARN_ON(ret);
1060 
1061 				for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1062 					kfree(rht_node->map[i]);
1063 
1064 				kfree(rht_node);
1065 			}
1066 		}
1067 	}
1068 
1069 	cpumask_copy(&sde->cpu_mask, new_mask);
1070 out:
1071 	mutex_unlock(&process_to_sde_mutex);
1072 out_free:
1073 	free_cpumask_var(mask);
1074 	free_cpumask_var(new_mask);
1075 	return ret ? : strnlen(buf, PAGE_SIZE);
1076 }
1077 
1078 ssize_t sdma_get_cpu_to_sde_map(struct sdma_engine *sde, char *buf)
1079 {
1080 	mutex_lock(&process_to_sde_mutex);
1081 	if (cpumask_empty(&sde->cpu_mask))
1082 		snprintf(buf, PAGE_SIZE, "%s\n", "empty");
1083 	else
1084 		cpumap_print_to_pagebuf(true, buf, &sde->cpu_mask);
1085 	mutex_unlock(&process_to_sde_mutex);
1086 	return strnlen(buf, PAGE_SIZE);
1087 }
1088 
1089 static void sdma_rht_free(void *ptr, void *arg)
1090 {
1091 	struct sdma_rht_node *rht_node = ptr;
1092 	int i;
1093 
1094 	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1095 		kfree(rht_node->map[i]);
1096 
1097 	kfree(rht_node);
1098 }
1099 
1100 /**
1101  * sdma_seqfile_dump_cpu_list() - debugfs dump the cpu to sdma mappings
1102  * @s: seq file
1103  * @dd: hfi1_devdata
1104  * @cpuid: cpu id
1105  *
1106  * This routine dumps the process to sde mappings per cpu
1107  */
1108 void sdma_seqfile_dump_cpu_list(struct seq_file *s,
1109 				struct hfi1_devdata *dd,
1110 				unsigned long cpuid)
1111 {
1112 	struct sdma_rht_node *rht_node;
1113 	int i, j;
1114 
1115 	rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpuid,
1116 					  sdma_rht_params);
1117 	if (!rht_node)
1118 		return;
1119 
1120 	seq_printf(s, "cpu%3lu: ", cpuid);
1121 	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1122 		if (!rht_node->map[i] || !rht_node->map[i]->ctr)
1123 			continue;
1124 
1125 		seq_printf(s, " vl%d: [", i);
1126 
1127 		for (j = 0; j < rht_node->map[i]->ctr; j++) {
1128 			if (!rht_node->map[i]->sde[j])
1129 				continue;
1130 
1131 			if (j > 0)
1132 				seq_puts(s, ",");
1133 
1134 			seq_printf(s, " sdma%2d",
1135 				   rht_node->map[i]->sde[j]->this_idx);
1136 		}
1137 		seq_puts(s, " ]");
1138 	}
1139 
1140 	seq_puts(s, "\n");
1141 }
1142 
1143 /*
1144  * Free the indicated map struct
1145  */
1146 static void sdma_map_free(struct sdma_vl_map *m)
1147 {
1148 	int i;
1149 
1150 	for (i = 0; m && i < m->actual_vls; i++)
1151 		kfree(m->map[i]);
1152 	kfree(m);
1153 }
1154 
1155 /*
1156  * Handle RCU callback
1157  */
1158 static void sdma_map_rcu_callback(struct rcu_head *list)
1159 {
1160 	struct sdma_vl_map *m = container_of(list, struct sdma_vl_map, list);
1161 
1162 	sdma_map_free(m);
1163 }
1164 
1165 /**
1166  * sdma_map_init - called when # vls change
1167  * @dd: hfi1_devdata
1168  * @port: port number
1169  * @num_vls: number of vls
1170  * @vl_engines: per vl engine mapping (optional)
1171  *
1172  * This routine changes the mapping based on the number of vls.
1173  *
1174  * vl_engines is used to specify a non-uniform vl/engine loading. NULL
1175  * implies auto computing the loading and giving each VLs a uniform
1176  * distribution of engines per VL.
1177  *
1178  * The auto algorithm computes the sde_per_vl and the number of extra
1179  * engines.  Any extra engines are added from the last VL on down.
1180  *
1181  * rcu locking is used here to control access to the mapping fields.
1182  *
1183  * If either the num_vls or num_sdma are non-power of 2, the array sizes
1184  * in the struct sdma_vl_map and the struct sdma_map_elem are rounded
1185  * up to the next highest power of 2 and the first entry is reused
1186  * in a round robin fashion.
1187  *
1188  * If an error occurs the map change is not done and the mapping is
1189  * not changed.
1190  *
1191  */
1192 int sdma_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_engines)
1193 {
1194 	int i, j;
1195 	int extra, sde_per_vl;
1196 	int engine = 0;
1197 	u8 lvl_engines[OPA_MAX_VLS];
1198 	struct sdma_vl_map *oldmap, *newmap;
1199 
1200 	if (!(dd->flags & HFI1_HAS_SEND_DMA))
1201 		return 0;
1202 
1203 	if (!vl_engines) {
1204 		/* truncate divide */
1205 		sde_per_vl = dd->num_sdma / num_vls;
1206 		/* extras */
1207 		extra = dd->num_sdma % num_vls;
1208 		vl_engines = lvl_engines;
1209 		/* add extras from last vl down */
1210 		for (i = num_vls - 1; i >= 0; i--, extra--)
1211 			vl_engines[i] = sde_per_vl + (extra > 0 ? 1 : 0);
1212 	}
1213 	/* build new map */
1214 	newmap = kzalloc(
1215 		sizeof(struct sdma_vl_map) +
1216 			roundup_pow_of_two(num_vls) *
1217 			sizeof(struct sdma_map_elem *),
1218 		GFP_KERNEL);
1219 	if (!newmap)
1220 		goto bail;
1221 	newmap->actual_vls = num_vls;
1222 	newmap->vls = roundup_pow_of_two(num_vls);
1223 	newmap->mask = (1 << ilog2(newmap->vls)) - 1;
1224 	/* initialize back-map */
1225 	for (i = 0; i < TXE_NUM_SDMA_ENGINES; i++)
1226 		newmap->engine_to_vl[i] = -1;
1227 	for (i = 0; i < newmap->vls; i++) {
1228 		/* save for wrap around */
1229 		int first_engine = engine;
1230 
1231 		if (i < newmap->actual_vls) {
1232 			int sz = roundup_pow_of_two(vl_engines[i]);
1233 
1234 			/* only allocate once */
1235 			newmap->map[i] = kzalloc(
1236 				sizeof(struct sdma_map_elem) +
1237 					sz * sizeof(struct sdma_engine *),
1238 				GFP_KERNEL);
1239 			if (!newmap->map[i])
1240 				goto bail;
1241 			newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
1242 			/* assign engines */
1243 			for (j = 0; j < sz; j++) {
1244 				newmap->map[i]->sde[j] =
1245 					&dd->per_sdma[engine];
1246 				if (++engine >= first_engine + vl_engines[i])
1247 					/* wrap back to first engine */
1248 					engine = first_engine;
1249 			}
1250 			/* assign back-map */
1251 			for (j = 0; j < vl_engines[i]; j++)
1252 				newmap->engine_to_vl[first_engine + j] = i;
1253 		} else {
1254 			/* just re-use entry without allocating */
1255 			newmap->map[i] = newmap->map[i % num_vls];
1256 		}
1257 		engine = first_engine + vl_engines[i];
1258 	}
1259 	/* newmap in hand, save old map */
1260 	spin_lock_irq(&dd->sde_map_lock);
1261 	oldmap = rcu_dereference_protected(dd->sdma_map,
1262 					   lockdep_is_held(&dd->sde_map_lock));
1263 
1264 	/* publish newmap */
1265 	rcu_assign_pointer(dd->sdma_map, newmap);
1266 
1267 	spin_unlock_irq(&dd->sde_map_lock);
1268 	/* success, free any old map after grace period */
1269 	if (oldmap)
1270 		call_rcu(&oldmap->list, sdma_map_rcu_callback);
1271 	return 0;
1272 bail:
1273 	/* free any partial allocation */
1274 	sdma_map_free(newmap);
1275 	return -ENOMEM;
1276 }
1277 
1278 /*
1279  * Clean up allocated memory.
1280  *
1281  * This routine is can be called regardless of the success of sdma_init()
1282  *
1283  */
1284 static void sdma_clean(struct hfi1_devdata *dd, size_t num_engines)
1285 {
1286 	size_t i;
1287 	struct sdma_engine *sde;
1288 
1289 	if (dd->sdma_pad_dma) {
1290 		dma_free_coherent(&dd->pcidev->dev, 4,
1291 				  (void *)dd->sdma_pad_dma,
1292 				  dd->sdma_pad_phys);
1293 		dd->sdma_pad_dma = NULL;
1294 		dd->sdma_pad_phys = 0;
1295 	}
1296 	if (dd->sdma_heads_dma) {
1297 		dma_free_coherent(&dd->pcidev->dev, dd->sdma_heads_size,
1298 				  (void *)dd->sdma_heads_dma,
1299 				  dd->sdma_heads_phys);
1300 		dd->sdma_heads_dma = NULL;
1301 		dd->sdma_heads_phys = 0;
1302 	}
1303 	for (i = 0; dd->per_sdma && i < num_engines; ++i) {
1304 		sde = &dd->per_sdma[i];
1305 
1306 		sde->head_dma = NULL;
1307 		sde->head_phys = 0;
1308 
1309 		if (sde->descq) {
1310 			dma_free_coherent(
1311 				&dd->pcidev->dev,
1312 				sde->descq_cnt * sizeof(u64[2]),
1313 				sde->descq,
1314 				sde->descq_phys
1315 			);
1316 			sde->descq = NULL;
1317 			sde->descq_phys = 0;
1318 		}
1319 		kvfree(sde->tx_ring);
1320 		sde->tx_ring = NULL;
1321 	}
1322 	spin_lock_irq(&dd->sde_map_lock);
1323 	sdma_map_free(rcu_access_pointer(dd->sdma_map));
1324 	RCU_INIT_POINTER(dd->sdma_map, NULL);
1325 	spin_unlock_irq(&dd->sde_map_lock);
1326 	synchronize_rcu();
1327 	kfree(dd->per_sdma);
1328 	dd->per_sdma = NULL;
1329 
1330 	if (dd->sdma_rht) {
1331 		rhashtable_free_and_destroy(dd->sdma_rht, sdma_rht_free, NULL);
1332 		kfree(dd->sdma_rht);
1333 		dd->sdma_rht = NULL;
1334 	}
1335 }
1336 
1337 /**
1338  * sdma_init() - called when device probed
1339  * @dd: hfi1_devdata
1340  * @port: port number (currently only zero)
1341  *
1342  * Initializes each sde and its csrs.
1343  * Interrupts are not required to be enabled.
1344  *
1345  * Returns:
1346  * 0 - success, -errno on failure
1347  */
1348 int sdma_init(struct hfi1_devdata *dd, u8 port)
1349 {
1350 	unsigned this_idx;
1351 	struct sdma_engine *sde;
1352 	struct rhashtable *tmp_sdma_rht;
1353 	u16 descq_cnt;
1354 	void *curr_head;
1355 	struct hfi1_pportdata *ppd = dd->pport + port;
1356 	u32 per_sdma_credits;
1357 	uint idle_cnt = sdma_idle_cnt;
1358 	size_t num_engines = dd->chip_sdma_engines;
1359 	int ret = -ENOMEM;
1360 
1361 	if (!HFI1_CAP_IS_KSET(SDMA)) {
1362 		HFI1_CAP_CLEAR(SDMA_AHG);
1363 		return 0;
1364 	}
1365 	if (mod_num_sdma &&
1366 	    /* can't exceed chip support */
1367 	    mod_num_sdma <= dd->chip_sdma_engines &&
1368 	    /* count must be >= vls */
1369 	    mod_num_sdma >= num_vls)
1370 		num_engines = mod_num_sdma;
1371 
1372 	dd_dev_info(dd, "SDMA mod_num_sdma: %u\n", mod_num_sdma);
1373 	dd_dev_info(dd, "SDMA chip_sdma_engines: %u\n", dd->chip_sdma_engines);
1374 	dd_dev_info(dd, "SDMA chip_sdma_mem_size: %u\n",
1375 		    dd->chip_sdma_mem_size);
1376 
1377 	per_sdma_credits =
1378 		dd->chip_sdma_mem_size / (num_engines * SDMA_BLOCK_SIZE);
1379 
1380 	/* set up freeze waitqueue */
1381 	init_waitqueue_head(&dd->sdma_unfreeze_wq);
1382 	atomic_set(&dd->sdma_unfreeze_count, 0);
1383 
1384 	descq_cnt = sdma_get_descq_cnt();
1385 	dd_dev_info(dd, "SDMA engines %zu descq_cnt %u\n",
1386 		    num_engines, descq_cnt);
1387 
1388 	/* alloc memory for array of send engines */
1389 	dd->per_sdma = kcalloc(num_engines, sizeof(*dd->per_sdma), GFP_KERNEL);
1390 	if (!dd->per_sdma)
1391 		return ret;
1392 
1393 	idle_cnt = ns_to_cclock(dd, idle_cnt);
1394 	if (idle_cnt)
1395 		dd->default_desc1 =
1396 			SDMA_DESC1_HEAD_TO_HOST_FLAG;
1397 	else
1398 		dd->default_desc1 =
1399 			SDMA_DESC1_INT_REQ_FLAG;
1400 
1401 	if (!sdma_desct_intr)
1402 		sdma_desct_intr = SDMA_DESC_INTR;
1403 
1404 	/* Allocate memory for SendDMA descriptor FIFOs */
1405 	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1406 		sde = &dd->per_sdma[this_idx];
1407 		sde->dd = dd;
1408 		sde->ppd = ppd;
1409 		sde->this_idx = this_idx;
1410 		sde->descq_cnt = descq_cnt;
1411 		sde->desc_avail = sdma_descq_freecnt(sde);
1412 		sde->sdma_shift = ilog2(descq_cnt);
1413 		sde->sdma_mask = (1 << sde->sdma_shift) - 1;
1414 
1415 		/* Create a mask specifically for each interrupt source */
1416 		sde->int_mask = (u64)1 << (0 * TXE_NUM_SDMA_ENGINES +
1417 					   this_idx);
1418 		sde->progress_mask = (u64)1 << (1 * TXE_NUM_SDMA_ENGINES +
1419 						this_idx);
1420 		sde->idle_mask = (u64)1 << (2 * TXE_NUM_SDMA_ENGINES +
1421 					    this_idx);
1422 		/* Create a combined mask to cover all 3 interrupt sources */
1423 		sde->imask = sde->int_mask | sde->progress_mask |
1424 			     sde->idle_mask;
1425 
1426 		spin_lock_init(&sde->tail_lock);
1427 		seqlock_init(&sde->head_lock);
1428 		spin_lock_init(&sde->senddmactrl_lock);
1429 		spin_lock_init(&sde->flushlist_lock);
1430 		/* insure there is always a zero bit */
1431 		sde->ahg_bits = 0xfffffffe00000000ULL;
1432 
1433 		sdma_set_state(sde, sdma_state_s00_hw_down);
1434 
1435 		/* set up reference counting */
1436 		kref_init(&sde->state.kref);
1437 		init_completion(&sde->state.comp);
1438 
1439 		INIT_LIST_HEAD(&sde->flushlist);
1440 		INIT_LIST_HEAD(&sde->dmawait);
1441 
1442 		sde->tail_csr =
1443 			get_kctxt_csr_addr(dd, this_idx, SD(TAIL));
1444 
1445 		tasklet_init(&sde->sdma_hw_clean_up_task, sdma_hw_clean_up_task,
1446 			     (unsigned long)sde);
1447 
1448 		tasklet_init(&sde->sdma_sw_clean_up_task, sdma_sw_clean_up_task,
1449 			     (unsigned long)sde);
1450 		INIT_WORK(&sde->err_halt_worker, sdma_err_halt_wait);
1451 		INIT_WORK(&sde->flush_worker, sdma_field_flush);
1452 
1453 		sde->progress_check_head = 0;
1454 
1455 		timer_setup(&sde->err_progress_check_timer,
1456 			    sdma_err_progress_check, 0);
1457 
1458 		sde->descq = dma_zalloc_coherent(
1459 			&dd->pcidev->dev,
1460 			descq_cnt * sizeof(u64[2]),
1461 			&sde->descq_phys,
1462 			GFP_KERNEL
1463 		);
1464 		if (!sde->descq)
1465 			goto bail;
1466 		sde->tx_ring =
1467 			kvzalloc_node(sizeof(struct sdma_txreq *) * descq_cnt,
1468 				      GFP_KERNEL, dd->node);
1469 		if (!sde->tx_ring)
1470 			goto bail;
1471 	}
1472 
1473 	dd->sdma_heads_size = L1_CACHE_BYTES * num_engines;
1474 	/* Allocate memory for DMA of head registers to memory */
1475 	dd->sdma_heads_dma = dma_zalloc_coherent(
1476 		&dd->pcidev->dev,
1477 		dd->sdma_heads_size,
1478 		&dd->sdma_heads_phys,
1479 		GFP_KERNEL
1480 	);
1481 	if (!dd->sdma_heads_dma) {
1482 		dd_dev_err(dd, "failed to allocate SendDMA head memory\n");
1483 		goto bail;
1484 	}
1485 
1486 	/* Allocate memory for pad */
1487 	dd->sdma_pad_dma = dma_zalloc_coherent(
1488 		&dd->pcidev->dev,
1489 		sizeof(u32),
1490 		&dd->sdma_pad_phys,
1491 		GFP_KERNEL
1492 	);
1493 	if (!dd->sdma_pad_dma) {
1494 		dd_dev_err(dd, "failed to allocate SendDMA pad memory\n");
1495 		goto bail;
1496 	}
1497 
1498 	/* assign each engine to different cacheline and init registers */
1499 	curr_head = (void *)dd->sdma_heads_dma;
1500 	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1501 		unsigned long phys_offset;
1502 
1503 		sde = &dd->per_sdma[this_idx];
1504 
1505 		sde->head_dma = curr_head;
1506 		curr_head += L1_CACHE_BYTES;
1507 		phys_offset = (unsigned long)sde->head_dma -
1508 			      (unsigned long)dd->sdma_heads_dma;
1509 		sde->head_phys = dd->sdma_heads_phys + phys_offset;
1510 		init_sdma_regs(sde, per_sdma_credits, idle_cnt);
1511 	}
1512 	dd->flags |= HFI1_HAS_SEND_DMA;
1513 	dd->flags |= idle_cnt ? HFI1_HAS_SDMA_TIMEOUT : 0;
1514 	dd->num_sdma = num_engines;
1515 	ret = sdma_map_init(dd, port, ppd->vls_operational, NULL);
1516 	if (ret < 0)
1517 		goto bail;
1518 
1519 	tmp_sdma_rht = kzalloc(sizeof(*tmp_sdma_rht), GFP_KERNEL);
1520 	if (!tmp_sdma_rht) {
1521 		ret = -ENOMEM;
1522 		goto bail;
1523 	}
1524 
1525 	ret = rhashtable_init(tmp_sdma_rht, &sdma_rht_params);
1526 	if (ret < 0)
1527 		goto bail;
1528 	dd->sdma_rht = tmp_sdma_rht;
1529 
1530 	dd_dev_info(dd, "SDMA num_sdma: %u\n", dd->num_sdma);
1531 	return 0;
1532 
1533 bail:
1534 	sdma_clean(dd, num_engines);
1535 	return ret;
1536 }
1537 
1538 /**
1539  * sdma_all_running() - called when the link goes up
1540  * @dd: hfi1_devdata
1541  *
1542  * This routine moves all engines to the running state.
1543  */
1544 void sdma_all_running(struct hfi1_devdata *dd)
1545 {
1546 	struct sdma_engine *sde;
1547 	unsigned int i;
1548 
1549 	/* move all engines to running */
1550 	for (i = 0; i < dd->num_sdma; ++i) {
1551 		sde = &dd->per_sdma[i];
1552 		sdma_process_event(sde, sdma_event_e30_go_running);
1553 	}
1554 }
1555 
1556 /**
1557  * sdma_all_idle() - called when the link goes down
1558  * @dd: hfi1_devdata
1559  *
1560  * This routine moves all engines to the idle state.
1561  */
1562 void sdma_all_idle(struct hfi1_devdata *dd)
1563 {
1564 	struct sdma_engine *sde;
1565 	unsigned int i;
1566 
1567 	/* idle all engines */
1568 	for (i = 0; i < dd->num_sdma; ++i) {
1569 		sde = &dd->per_sdma[i];
1570 		sdma_process_event(sde, sdma_event_e70_go_idle);
1571 	}
1572 }
1573 
1574 /**
1575  * sdma_start() - called to kick off state processing for all engines
1576  * @dd: hfi1_devdata
1577  *
1578  * This routine is for kicking off the state processing for all required
1579  * sdma engines.  Interrupts need to be working at this point.
1580  *
1581  */
1582 void sdma_start(struct hfi1_devdata *dd)
1583 {
1584 	unsigned i;
1585 	struct sdma_engine *sde;
1586 
1587 	/* kick off the engines state processing */
1588 	for (i = 0; i < dd->num_sdma; ++i) {
1589 		sde = &dd->per_sdma[i];
1590 		sdma_process_event(sde, sdma_event_e10_go_hw_start);
1591 	}
1592 }
1593 
1594 /**
1595  * sdma_exit() - used when module is removed
1596  * @dd: hfi1_devdata
1597  */
1598 void sdma_exit(struct hfi1_devdata *dd)
1599 {
1600 	unsigned this_idx;
1601 	struct sdma_engine *sde;
1602 
1603 	for (this_idx = 0; dd->per_sdma && this_idx < dd->num_sdma;
1604 			++this_idx) {
1605 		sde = &dd->per_sdma[this_idx];
1606 		if (!list_empty(&sde->dmawait))
1607 			dd_dev_err(dd, "sde %u: dmawait list not empty!\n",
1608 				   sde->this_idx);
1609 		sdma_process_event(sde, sdma_event_e00_go_hw_down);
1610 
1611 		del_timer_sync(&sde->err_progress_check_timer);
1612 
1613 		/*
1614 		 * This waits for the state machine to exit so it is not
1615 		 * necessary to kill the sdma_sw_clean_up_task to make sure
1616 		 * it is not running.
1617 		 */
1618 		sdma_finalput(&sde->state);
1619 	}
1620 	sdma_clean(dd, dd->num_sdma);
1621 }
1622 
1623 /*
1624  * unmap the indicated descriptor
1625  */
1626 static inline void sdma_unmap_desc(
1627 	struct hfi1_devdata *dd,
1628 	struct sdma_desc *descp)
1629 {
1630 	switch (sdma_mapping_type(descp)) {
1631 	case SDMA_MAP_SINGLE:
1632 		dma_unmap_single(
1633 			&dd->pcidev->dev,
1634 			sdma_mapping_addr(descp),
1635 			sdma_mapping_len(descp),
1636 			DMA_TO_DEVICE);
1637 		break;
1638 	case SDMA_MAP_PAGE:
1639 		dma_unmap_page(
1640 			&dd->pcidev->dev,
1641 			sdma_mapping_addr(descp),
1642 			sdma_mapping_len(descp),
1643 			DMA_TO_DEVICE);
1644 		break;
1645 	}
1646 }
1647 
1648 /*
1649  * return the mode as indicated by the first
1650  * descriptor in the tx.
1651  */
1652 static inline u8 ahg_mode(struct sdma_txreq *tx)
1653 {
1654 	return (tx->descp[0].qw[1] & SDMA_DESC1_HEADER_MODE_SMASK)
1655 		>> SDMA_DESC1_HEADER_MODE_SHIFT;
1656 }
1657 
1658 /**
1659  * __sdma_txclean() - clean tx of mappings, descp *kmalloc's
1660  * @dd: hfi1_devdata for unmapping
1661  * @tx: tx request to clean
1662  *
1663  * This is used in the progress routine to clean the tx or
1664  * by the ULP to toss an in-process tx build.
1665  *
1666  * The code can be called multiple times without issue.
1667  *
1668  */
1669 void __sdma_txclean(
1670 	struct hfi1_devdata *dd,
1671 	struct sdma_txreq *tx)
1672 {
1673 	u16 i;
1674 
1675 	if (tx->num_desc) {
1676 		u8 skip = 0, mode = ahg_mode(tx);
1677 
1678 		/* unmap first */
1679 		sdma_unmap_desc(dd, &tx->descp[0]);
1680 		/* determine number of AHG descriptors to skip */
1681 		if (mode > SDMA_AHG_APPLY_UPDATE1)
1682 			skip = mode >> 1;
1683 		for (i = 1 + skip; i < tx->num_desc; i++)
1684 			sdma_unmap_desc(dd, &tx->descp[i]);
1685 		tx->num_desc = 0;
1686 	}
1687 	kfree(tx->coalesce_buf);
1688 	tx->coalesce_buf = NULL;
1689 	/* kmalloc'ed descp */
1690 	if (unlikely(tx->desc_limit > ARRAY_SIZE(tx->descs))) {
1691 		tx->desc_limit = ARRAY_SIZE(tx->descs);
1692 		kfree(tx->descp);
1693 	}
1694 }
1695 
1696 static inline u16 sdma_gethead(struct sdma_engine *sde)
1697 {
1698 	struct hfi1_devdata *dd = sde->dd;
1699 	int use_dmahead;
1700 	u16 hwhead;
1701 
1702 #ifdef CONFIG_SDMA_VERBOSITY
1703 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1704 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1705 #endif
1706 
1707 retry:
1708 	use_dmahead = HFI1_CAP_IS_KSET(USE_SDMA_HEAD) && __sdma_running(sde) &&
1709 					(dd->flags & HFI1_HAS_SDMA_TIMEOUT);
1710 	hwhead = use_dmahead ?
1711 		(u16)le64_to_cpu(*sde->head_dma) :
1712 		(u16)read_sde_csr(sde, SD(HEAD));
1713 
1714 	if (unlikely(HFI1_CAP_IS_KSET(SDMA_HEAD_CHECK))) {
1715 		u16 cnt;
1716 		u16 swtail;
1717 		u16 swhead;
1718 		int sane;
1719 
1720 		swhead = sde->descq_head & sde->sdma_mask;
1721 		/* this code is really bad for cache line trading */
1722 		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1723 		cnt = sde->descq_cnt;
1724 
1725 		if (swhead < swtail)
1726 			/* not wrapped */
1727 			sane = (hwhead >= swhead) & (hwhead <= swtail);
1728 		else if (swhead > swtail)
1729 			/* wrapped around */
1730 			sane = ((hwhead >= swhead) && (hwhead < cnt)) ||
1731 				(hwhead <= swtail);
1732 		else
1733 			/* empty */
1734 			sane = (hwhead == swhead);
1735 
1736 		if (unlikely(!sane)) {
1737 			dd_dev_err(dd, "SDMA(%u) bad head (%s) hwhd=%hu swhd=%hu swtl=%hu cnt=%hu\n",
1738 				   sde->this_idx,
1739 				   use_dmahead ? "dma" : "kreg",
1740 				   hwhead, swhead, swtail, cnt);
1741 			if (use_dmahead) {
1742 				/* try one more time, using csr */
1743 				use_dmahead = 0;
1744 				goto retry;
1745 			}
1746 			/* proceed as if no progress */
1747 			hwhead = swhead;
1748 		}
1749 	}
1750 	return hwhead;
1751 }
1752 
1753 /*
1754  * This is called when there are send DMA descriptors that might be
1755  * available.
1756  *
1757  * This is called with head_lock held.
1758  */
1759 static void sdma_desc_avail(struct sdma_engine *sde, uint avail)
1760 {
1761 	struct iowait *wait, *nw;
1762 	struct iowait *waits[SDMA_WAIT_BATCH_SIZE];
1763 	uint i, n = 0, seq, max_idx = 0;
1764 	struct sdma_txreq *stx;
1765 	struct hfi1_ibdev *dev = &sde->dd->verbs_dev;
1766 	u8 max_starved_cnt = 0;
1767 
1768 #ifdef CONFIG_SDMA_VERBOSITY
1769 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n", sde->this_idx,
1770 		   slashstrip(__FILE__), __LINE__, __func__);
1771 	dd_dev_err(sde->dd, "avail: %u\n", avail);
1772 #endif
1773 
1774 	do {
1775 		seq = read_seqbegin(&dev->iowait_lock);
1776 		if (!list_empty(&sde->dmawait)) {
1777 			/* at least one item */
1778 			write_seqlock(&dev->iowait_lock);
1779 			/* Harvest waiters wanting DMA descriptors */
1780 			list_for_each_entry_safe(
1781 					wait,
1782 					nw,
1783 					&sde->dmawait,
1784 					list) {
1785 				u16 num_desc = 0;
1786 
1787 				if (!wait->wakeup)
1788 					continue;
1789 				if (n == ARRAY_SIZE(waits))
1790 					break;
1791 				if (!list_empty(&wait->tx_head)) {
1792 					stx = list_first_entry(
1793 						&wait->tx_head,
1794 						struct sdma_txreq,
1795 						list);
1796 					num_desc = stx->num_desc;
1797 				}
1798 				if (num_desc > avail)
1799 					break;
1800 				avail -= num_desc;
1801 				/* Find the most starved wait memeber */
1802 				iowait_starve_find_max(wait, &max_starved_cnt,
1803 						       n, &max_idx);
1804 				list_del_init(&wait->list);
1805 				waits[n++] = wait;
1806 			}
1807 			write_sequnlock(&dev->iowait_lock);
1808 			break;
1809 		}
1810 	} while (read_seqretry(&dev->iowait_lock, seq));
1811 
1812 	/* Schedule the most starved one first */
1813 	if (n)
1814 		waits[max_idx]->wakeup(waits[max_idx], SDMA_AVAIL_REASON);
1815 
1816 	for (i = 0; i < n; i++)
1817 		if (i != max_idx)
1818 			waits[i]->wakeup(waits[i], SDMA_AVAIL_REASON);
1819 }
1820 
1821 /* head_lock must be held */
1822 static void sdma_make_progress(struct sdma_engine *sde, u64 status)
1823 {
1824 	struct sdma_txreq *txp = NULL;
1825 	int progress = 0;
1826 	u16 hwhead, swhead;
1827 	int idle_check_done = 0;
1828 
1829 	hwhead = sdma_gethead(sde);
1830 
1831 	/* The reason for some of the complexity of this code is that
1832 	 * not all descriptors have corresponding txps.  So, we have to
1833 	 * be able to skip over descs until we wander into the range of
1834 	 * the next txp on the list.
1835 	 */
1836 
1837 retry:
1838 	txp = get_txhead(sde);
1839 	swhead = sde->descq_head & sde->sdma_mask;
1840 	trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1841 	while (swhead != hwhead) {
1842 		/* advance head, wrap if needed */
1843 		swhead = ++sde->descq_head & sde->sdma_mask;
1844 
1845 		/* if now past this txp's descs, do the callback */
1846 		if (txp && txp->next_descq_idx == swhead) {
1847 			/* remove from list */
1848 			sde->tx_ring[sde->tx_head++ & sde->sdma_mask] = NULL;
1849 			complete_tx(sde, txp, SDMA_TXREQ_S_OK);
1850 			/* see if there is another txp */
1851 			txp = get_txhead(sde);
1852 		}
1853 		trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1854 		progress++;
1855 	}
1856 
1857 	/*
1858 	 * The SDMA idle interrupt is not guaranteed to be ordered with respect
1859 	 * to updates to the the dma_head location in host memory. The head
1860 	 * value read might not be fully up to date. If there are pending
1861 	 * descriptors and the SDMA idle interrupt fired then read from the
1862 	 * CSR SDMA head instead to get the latest value from the hardware.
1863 	 * The hardware SDMA head should be read at most once in this invocation
1864 	 * of sdma_make_progress(..) which is ensured by idle_check_done flag
1865 	 */
1866 	if ((status & sde->idle_mask) && !idle_check_done) {
1867 		u16 swtail;
1868 
1869 		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1870 		if (swtail != hwhead) {
1871 			hwhead = (u16)read_sde_csr(sde, SD(HEAD));
1872 			idle_check_done = 1;
1873 			goto retry;
1874 		}
1875 	}
1876 
1877 	sde->last_status = status;
1878 	if (progress)
1879 		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
1880 }
1881 
1882 /*
1883  * sdma_engine_interrupt() - interrupt handler for engine
1884  * @sde: sdma engine
1885  * @status: sdma interrupt reason
1886  *
1887  * Status is a mask of the 3 possible interrupts for this engine.  It will
1888  * contain bits _only_ for this SDMA engine.  It will contain at least one
1889  * bit, it may contain more.
1890  */
1891 void sdma_engine_interrupt(struct sdma_engine *sde, u64 status)
1892 {
1893 	trace_hfi1_sdma_engine_interrupt(sde, status);
1894 	write_seqlock(&sde->head_lock);
1895 	sdma_set_desc_cnt(sde, sdma_desct_intr);
1896 	if (status & sde->idle_mask)
1897 		sde->idle_int_cnt++;
1898 	else if (status & sde->progress_mask)
1899 		sde->progress_int_cnt++;
1900 	else if (status & sde->int_mask)
1901 		sde->sdma_int_cnt++;
1902 	sdma_make_progress(sde, status);
1903 	write_sequnlock(&sde->head_lock);
1904 }
1905 
1906 /**
1907  * sdma_engine_error() - error handler for engine
1908  * @sde: sdma engine
1909  * @status: sdma interrupt reason
1910  */
1911 void sdma_engine_error(struct sdma_engine *sde, u64 status)
1912 {
1913 	unsigned long flags;
1914 
1915 #ifdef CONFIG_SDMA_VERBOSITY
1916 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) error status 0x%llx state %s\n",
1917 		   sde->this_idx,
1918 		   (unsigned long long)status,
1919 		   sdma_state_names[sde->state.current_state]);
1920 #endif
1921 	spin_lock_irqsave(&sde->tail_lock, flags);
1922 	write_seqlock(&sde->head_lock);
1923 	if (status & ALL_SDMA_ENG_HALT_ERRS)
1924 		__sdma_process_event(sde, sdma_event_e60_hw_halted);
1925 	if (status & ~SD(ENG_ERR_STATUS_SDMA_HALT_ERR_SMASK)) {
1926 		dd_dev_err(sde->dd,
1927 			   "SDMA (%u) engine error: 0x%llx state %s\n",
1928 			   sde->this_idx,
1929 			   (unsigned long long)status,
1930 			   sdma_state_names[sde->state.current_state]);
1931 		dump_sdma_state(sde);
1932 	}
1933 	write_sequnlock(&sde->head_lock);
1934 	spin_unlock_irqrestore(&sde->tail_lock, flags);
1935 }
1936 
1937 static void sdma_sendctrl(struct sdma_engine *sde, unsigned op)
1938 {
1939 	u64 set_senddmactrl = 0;
1940 	u64 clr_senddmactrl = 0;
1941 	unsigned long flags;
1942 
1943 #ifdef CONFIG_SDMA_VERBOSITY
1944 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) senddmactrl E=%d I=%d H=%d C=%d\n",
1945 		   sde->this_idx,
1946 		   (op & SDMA_SENDCTRL_OP_ENABLE) ? 1 : 0,
1947 		   (op & SDMA_SENDCTRL_OP_INTENABLE) ? 1 : 0,
1948 		   (op & SDMA_SENDCTRL_OP_HALT) ? 1 : 0,
1949 		   (op & SDMA_SENDCTRL_OP_CLEANUP) ? 1 : 0);
1950 #endif
1951 
1952 	if (op & SDMA_SENDCTRL_OP_ENABLE)
1953 		set_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1954 	else
1955 		clr_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1956 
1957 	if (op & SDMA_SENDCTRL_OP_INTENABLE)
1958 		set_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1959 	else
1960 		clr_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1961 
1962 	if (op & SDMA_SENDCTRL_OP_HALT)
1963 		set_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1964 	else
1965 		clr_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1966 
1967 	spin_lock_irqsave(&sde->senddmactrl_lock, flags);
1968 
1969 	sde->p_senddmactrl |= set_senddmactrl;
1970 	sde->p_senddmactrl &= ~clr_senddmactrl;
1971 
1972 	if (op & SDMA_SENDCTRL_OP_CLEANUP)
1973 		write_sde_csr(sde, SD(CTRL),
1974 			      sde->p_senddmactrl |
1975 			      SD(CTRL_SDMA_CLEANUP_SMASK));
1976 	else
1977 		write_sde_csr(sde, SD(CTRL), sde->p_senddmactrl);
1978 
1979 	spin_unlock_irqrestore(&sde->senddmactrl_lock, flags);
1980 
1981 #ifdef CONFIG_SDMA_VERBOSITY
1982 	sdma_dumpstate(sde);
1983 #endif
1984 }
1985 
1986 static void sdma_setlengen(struct sdma_engine *sde)
1987 {
1988 #ifdef CONFIG_SDMA_VERBOSITY
1989 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1990 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1991 #endif
1992 
1993 	/*
1994 	 * Set SendDmaLenGen and clear-then-set the MSB of the generation
1995 	 * count to enable generation checking and load the internal
1996 	 * generation counter.
1997 	 */
1998 	write_sde_csr(sde, SD(LEN_GEN),
1999 		      (sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT));
2000 	write_sde_csr(sde, SD(LEN_GEN),
2001 		      ((sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT)) |
2002 		      (4ULL << SD(LEN_GEN_GENERATION_SHIFT)));
2003 }
2004 
2005 static inline void sdma_update_tail(struct sdma_engine *sde, u16 tail)
2006 {
2007 	/* Commit writes to memory and advance the tail on the chip */
2008 	smp_wmb(); /* see get_txhead() */
2009 	writeq(tail, sde->tail_csr);
2010 }
2011 
2012 /*
2013  * This is called when changing to state s10_hw_start_up_halt_wait as
2014  * a result of send buffer errors or send DMA descriptor errors.
2015  */
2016 static void sdma_hw_start_up(struct sdma_engine *sde)
2017 {
2018 	u64 reg;
2019 
2020 #ifdef CONFIG_SDMA_VERBOSITY
2021 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2022 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2023 #endif
2024 
2025 	sdma_setlengen(sde);
2026 	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2027 	*sde->head_dma = 0;
2028 
2029 	reg = SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_MASK) <<
2030 	      SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_SHIFT);
2031 	write_sde_csr(sde, SD(ENG_ERR_CLEAR), reg);
2032 }
2033 
2034 /*
2035  * set_sdma_integrity
2036  *
2037  * Set the SEND_DMA_CHECK_ENABLE register for send DMA engine 'sde'.
2038  */
2039 static void set_sdma_integrity(struct sdma_engine *sde)
2040 {
2041 	struct hfi1_devdata *dd = sde->dd;
2042 
2043 	write_sde_csr(sde, SD(CHECK_ENABLE),
2044 		      hfi1_pkt_base_sdma_integrity(dd));
2045 }
2046 
2047 static void init_sdma_regs(
2048 	struct sdma_engine *sde,
2049 	u32 credits,
2050 	uint idle_cnt)
2051 {
2052 	u8 opval, opmask;
2053 #ifdef CONFIG_SDMA_VERBOSITY
2054 	struct hfi1_devdata *dd = sde->dd;
2055 
2056 	dd_dev_err(dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2057 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2058 #endif
2059 
2060 	write_sde_csr(sde, SD(BASE_ADDR), sde->descq_phys);
2061 	sdma_setlengen(sde);
2062 	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2063 	write_sde_csr(sde, SD(RELOAD_CNT), idle_cnt);
2064 	write_sde_csr(sde, SD(DESC_CNT), 0);
2065 	write_sde_csr(sde, SD(HEAD_ADDR), sde->head_phys);
2066 	write_sde_csr(sde, SD(MEMORY),
2067 		      ((u64)credits << SD(MEMORY_SDMA_MEMORY_CNT_SHIFT)) |
2068 		      ((u64)(credits * sde->this_idx) <<
2069 		       SD(MEMORY_SDMA_MEMORY_INDEX_SHIFT)));
2070 	write_sde_csr(sde, SD(ENG_ERR_MASK), ~0ull);
2071 	set_sdma_integrity(sde);
2072 	opmask = OPCODE_CHECK_MASK_DISABLED;
2073 	opval = OPCODE_CHECK_VAL_DISABLED;
2074 	write_sde_csr(sde, SD(CHECK_OPCODE),
2075 		      (opmask << SEND_CTXT_CHECK_OPCODE_MASK_SHIFT) |
2076 		      (opval << SEND_CTXT_CHECK_OPCODE_VALUE_SHIFT));
2077 }
2078 
2079 #ifdef CONFIG_SDMA_VERBOSITY
2080 
2081 #define sdma_dumpstate_helper0(reg) do { \
2082 		csr = read_csr(sde->dd, reg); \
2083 		dd_dev_err(sde->dd, "%36s     0x%016llx\n", #reg, csr); \
2084 	} while (0)
2085 
2086 #define sdma_dumpstate_helper(reg) do { \
2087 		csr = read_sde_csr(sde, reg); \
2088 		dd_dev_err(sde->dd, "%36s[%02u] 0x%016llx\n", \
2089 			#reg, sde->this_idx, csr); \
2090 	} while (0)
2091 
2092 #define sdma_dumpstate_helper2(reg) do { \
2093 		csr = read_csr(sde->dd, reg + (8 * i)); \
2094 		dd_dev_err(sde->dd, "%33s_%02u     0x%016llx\n", \
2095 				#reg, i, csr); \
2096 	} while (0)
2097 
2098 void sdma_dumpstate(struct sdma_engine *sde)
2099 {
2100 	u64 csr;
2101 	unsigned i;
2102 
2103 	sdma_dumpstate_helper(SD(CTRL));
2104 	sdma_dumpstate_helper(SD(STATUS));
2105 	sdma_dumpstate_helper0(SD(ERR_STATUS));
2106 	sdma_dumpstate_helper0(SD(ERR_MASK));
2107 	sdma_dumpstate_helper(SD(ENG_ERR_STATUS));
2108 	sdma_dumpstate_helper(SD(ENG_ERR_MASK));
2109 
2110 	for (i = 0; i < CCE_NUM_INT_CSRS; ++i) {
2111 		sdma_dumpstate_helper2(CCE_INT_STATUS);
2112 		sdma_dumpstate_helper2(CCE_INT_MASK);
2113 		sdma_dumpstate_helper2(CCE_INT_BLOCKED);
2114 	}
2115 
2116 	sdma_dumpstate_helper(SD(TAIL));
2117 	sdma_dumpstate_helper(SD(HEAD));
2118 	sdma_dumpstate_helper(SD(PRIORITY_THLD));
2119 	sdma_dumpstate_helper(SD(IDLE_CNT));
2120 	sdma_dumpstate_helper(SD(RELOAD_CNT));
2121 	sdma_dumpstate_helper(SD(DESC_CNT));
2122 	sdma_dumpstate_helper(SD(DESC_FETCHED_CNT));
2123 	sdma_dumpstate_helper(SD(MEMORY));
2124 	sdma_dumpstate_helper0(SD(ENGINES));
2125 	sdma_dumpstate_helper0(SD(MEM_SIZE));
2126 	/* sdma_dumpstate_helper(SEND_EGRESS_SEND_DMA_STATUS);  */
2127 	sdma_dumpstate_helper(SD(BASE_ADDR));
2128 	sdma_dumpstate_helper(SD(LEN_GEN));
2129 	sdma_dumpstate_helper(SD(HEAD_ADDR));
2130 	sdma_dumpstate_helper(SD(CHECK_ENABLE));
2131 	sdma_dumpstate_helper(SD(CHECK_VL));
2132 	sdma_dumpstate_helper(SD(CHECK_JOB_KEY));
2133 	sdma_dumpstate_helper(SD(CHECK_PARTITION_KEY));
2134 	sdma_dumpstate_helper(SD(CHECK_SLID));
2135 	sdma_dumpstate_helper(SD(CHECK_OPCODE));
2136 }
2137 #endif
2138 
2139 static void dump_sdma_state(struct sdma_engine *sde)
2140 {
2141 	struct hw_sdma_desc *descqp;
2142 	u64 desc[2];
2143 	u64 addr;
2144 	u8 gen;
2145 	u16 len;
2146 	u16 head, tail, cnt;
2147 
2148 	head = sde->descq_head & sde->sdma_mask;
2149 	tail = sde->descq_tail & sde->sdma_mask;
2150 	cnt = sdma_descq_freecnt(sde);
2151 
2152 	dd_dev_err(sde->dd,
2153 		   "SDMA (%u) descq_head: %u descq_tail: %u freecnt: %u FLE %d\n",
2154 		   sde->this_idx, head, tail, cnt,
2155 		   !list_empty(&sde->flushlist));
2156 
2157 	/* print info for each entry in the descriptor queue */
2158 	while (head != tail) {
2159 		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2160 
2161 		descqp = &sde->descq[head];
2162 		desc[0] = le64_to_cpu(descqp->qw[0]);
2163 		desc[1] = le64_to_cpu(descqp->qw[1]);
2164 		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2165 		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2166 				'H' : '-';
2167 		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2168 		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2169 		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2170 			& SDMA_DESC0_PHY_ADDR_MASK;
2171 		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2172 			& SDMA_DESC1_GENERATION_MASK;
2173 		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2174 			& SDMA_DESC0_BYTE_COUNT_MASK;
2175 		dd_dev_err(sde->dd,
2176 			   "SDMA sdmadesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2177 			   head, flags, addr, gen, len);
2178 		dd_dev_err(sde->dd,
2179 			   "\tdesc0:0x%016llx desc1 0x%016llx\n",
2180 			   desc[0], desc[1]);
2181 		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2182 			dd_dev_err(sde->dd,
2183 				   "\taidx: %u amode: %u alen: %u\n",
2184 				   (u8)((desc[1] &
2185 					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2186 					SDMA_DESC1_HEADER_INDEX_SHIFT),
2187 				   (u8)((desc[1] &
2188 					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2189 					SDMA_DESC1_HEADER_MODE_SHIFT),
2190 				   (u8)((desc[1] &
2191 					 SDMA_DESC1_HEADER_DWS_SMASK) >>
2192 					SDMA_DESC1_HEADER_DWS_SHIFT));
2193 		head++;
2194 		head &= sde->sdma_mask;
2195 	}
2196 }
2197 
2198 #define SDE_FMT \
2199 	"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"
2200 /**
2201  * sdma_seqfile_dump_sde() - debugfs dump of sde
2202  * @s: seq file
2203  * @sde: send dma engine to dump
2204  *
2205  * This routine dumps the sde to the indicated seq file.
2206  */
2207 void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *sde)
2208 {
2209 	u16 head, tail;
2210 	struct hw_sdma_desc *descqp;
2211 	u64 desc[2];
2212 	u64 addr;
2213 	u8 gen;
2214 	u16 len;
2215 
2216 	head = sde->descq_head & sde->sdma_mask;
2217 	tail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
2218 	seq_printf(s, SDE_FMT, sde->this_idx,
2219 		   sde->cpu,
2220 		   sdma_state_name(sde->state.current_state),
2221 		   (unsigned long long)read_sde_csr(sde, SD(CTRL)),
2222 		   (unsigned long long)read_sde_csr(sde, SD(STATUS)),
2223 		   (unsigned long long)read_sde_csr(sde, SD(ENG_ERR_STATUS)),
2224 		   (unsigned long long)read_sde_csr(sde, SD(TAIL)), tail,
2225 		   (unsigned long long)read_sde_csr(sde, SD(HEAD)), head,
2226 		   (unsigned long long)le64_to_cpu(*sde->head_dma),
2227 		   (unsigned long long)read_sde_csr(sde, SD(MEMORY)),
2228 		   (unsigned long long)read_sde_csr(sde, SD(LEN_GEN)),
2229 		   (unsigned long long)read_sde_csr(sde, SD(RELOAD_CNT)),
2230 		   (unsigned long long)sde->last_status,
2231 		   (unsigned long long)sde->ahg_bits,
2232 		   sde->tx_tail,
2233 		   sde->tx_head,
2234 		   sde->descq_tail,
2235 		   sde->descq_head,
2236 		   !list_empty(&sde->flushlist),
2237 		   sde->descq_full_count,
2238 		   (unsigned long long)read_sde_csr(sde, SEND_DMA_CHECK_SLID));
2239 
2240 	/* print info for each entry in the descriptor queue */
2241 	while (head != tail) {
2242 		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2243 
2244 		descqp = &sde->descq[head];
2245 		desc[0] = le64_to_cpu(descqp->qw[0]);
2246 		desc[1] = le64_to_cpu(descqp->qw[1]);
2247 		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2248 		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2249 				'H' : '-';
2250 		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2251 		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2252 		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2253 			& SDMA_DESC0_PHY_ADDR_MASK;
2254 		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2255 			& SDMA_DESC1_GENERATION_MASK;
2256 		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2257 			& SDMA_DESC0_BYTE_COUNT_MASK;
2258 		seq_printf(s,
2259 			   "\tdesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2260 			   head, flags, addr, gen, len);
2261 		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2262 			seq_printf(s, "\t\tahgidx: %u ahgmode: %u\n",
2263 				   (u8)((desc[1] &
2264 					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2265 					SDMA_DESC1_HEADER_INDEX_SHIFT),
2266 				   (u8)((desc[1] &
2267 					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2268 					SDMA_DESC1_HEADER_MODE_SHIFT));
2269 		head = (head + 1) & sde->sdma_mask;
2270 	}
2271 }
2272 
2273 /*
2274  * add the generation number into
2275  * the qw1 and return
2276  */
2277 static inline u64 add_gen(struct sdma_engine *sde, u64 qw1)
2278 {
2279 	u8 generation = (sde->descq_tail >> sde->sdma_shift) & 3;
2280 
2281 	qw1 &= ~SDMA_DESC1_GENERATION_SMASK;
2282 	qw1 |= ((u64)generation & SDMA_DESC1_GENERATION_MASK)
2283 			<< SDMA_DESC1_GENERATION_SHIFT;
2284 	return qw1;
2285 }
2286 
2287 /*
2288  * This routine submits the indicated tx
2289  *
2290  * Space has already been guaranteed and
2291  * tail side of ring is locked.
2292  *
2293  * The hardware tail update is done
2294  * in the caller and that is facilitated
2295  * by returning the new tail.
2296  *
2297  * There is special case logic for ahg
2298  * to not add the generation number for
2299  * up to 2 descriptors that follow the
2300  * first descriptor.
2301  *
2302  */
2303 static inline u16 submit_tx(struct sdma_engine *sde, struct sdma_txreq *tx)
2304 {
2305 	int i;
2306 	u16 tail;
2307 	struct sdma_desc *descp = tx->descp;
2308 	u8 skip = 0, mode = ahg_mode(tx);
2309 
2310 	tail = sde->descq_tail & sde->sdma_mask;
2311 	sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2312 	sde->descq[tail].qw[1] = cpu_to_le64(add_gen(sde, descp->qw[1]));
2313 	trace_hfi1_sdma_descriptor(sde, descp->qw[0], descp->qw[1],
2314 				   tail, &sde->descq[tail]);
2315 	tail = ++sde->descq_tail & sde->sdma_mask;
2316 	descp++;
2317 	if (mode > SDMA_AHG_APPLY_UPDATE1)
2318 		skip = mode >> 1;
2319 	for (i = 1; i < tx->num_desc; i++, descp++) {
2320 		u64 qw1;
2321 
2322 		sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2323 		if (skip) {
2324 			/* edits don't have generation */
2325 			qw1 = descp->qw[1];
2326 			skip--;
2327 		} else {
2328 			/* replace generation with real one for non-edits */
2329 			qw1 = add_gen(sde, descp->qw[1]);
2330 		}
2331 		sde->descq[tail].qw[1] = cpu_to_le64(qw1);
2332 		trace_hfi1_sdma_descriptor(sde, descp->qw[0], qw1,
2333 					   tail, &sde->descq[tail]);
2334 		tail = ++sde->descq_tail & sde->sdma_mask;
2335 	}
2336 	tx->next_descq_idx = tail;
2337 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2338 	tx->sn = sde->tail_sn++;
2339 	trace_hfi1_sdma_in_sn(sde, tx->sn);
2340 	WARN_ON_ONCE(sde->tx_ring[sde->tx_tail & sde->sdma_mask]);
2341 #endif
2342 	sde->tx_ring[sde->tx_tail++ & sde->sdma_mask] = tx;
2343 	sde->desc_avail -= tx->num_desc;
2344 	return tail;
2345 }
2346 
2347 /*
2348  * Check for progress
2349  */
2350 static int sdma_check_progress(
2351 	struct sdma_engine *sde,
2352 	struct iowait *wait,
2353 	struct sdma_txreq *tx,
2354 	bool pkts_sent)
2355 {
2356 	int ret;
2357 
2358 	sde->desc_avail = sdma_descq_freecnt(sde);
2359 	if (tx->num_desc <= sde->desc_avail)
2360 		return -EAGAIN;
2361 	/* pulse the head_lock */
2362 	if (wait && wait->sleep) {
2363 		unsigned seq;
2364 
2365 		seq = raw_seqcount_begin(
2366 			(const seqcount_t *)&sde->head_lock.seqcount);
2367 		ret = wait->sleep(sde, wait, tx, seq, pkts_sent);
2368 		if (ret == -EAGAIN)
2369 			sde->desc_avail = sdma_descq_freecnt(sde);
2370 	} else {
2371 		ret = -EBUSY;
2372 	}
2373 	return ret;
2374 }
2375 
2376 /**
2377  * sdma_send_txreq() - submit a tx req to ring
2378  * @sde: sdma engine to use
2379  * @wait: wait structure to use when full (may be NULL)
2380  * @tx: sdma_txreq to submit
2381  * @pkts_sent: has any packet been sent yet?
2382  *
2383  * The call submits the tx into the ring.  If a iowait structure is non-NULL
2384  * the packet will be queued to the list in wait.
2385  *
2386  * Return:
2387  * 0 - Success, -EINVAL - sdma_txreq incomplete, -EBUSY - no space in
2388  * ring (wait == NULL)
2389  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2390  */
2391 int sdma_send_txreq(struct sdma_engine *sde,
2392 		    struct iowait *wait,
2393 		    struct sdma_txreq *tx,
2394 		    bool pkts_sent)
2395 {
2396 	int ret = 0;
2397 	u16 tail;
2398 	unsigned long flags;
2399 
2400 	/* user should have supplied entire packet */
2401 	if (unlikely(tx->tlen))
2402 		return -EINVAL;
2403 	tx->wait = wait;
2404 	spin_lock_irqsave(&sde->tail_lock, flags);
2405 retry:
2406 	if (unlikely(!__sdma_running(sde)))
2407 		goto unlock_noconn;
2408 	if (unlikely(tx->num_desc > sde->desc_avail))
2409 		goto nodesc;
2410 	tail = submit_tx(sde, tx);
2411 	if (wait)
2412 		iowait_sdma_inc(wait);
2413 	sdma_update_tail(sde, tail);
2414 unlock:
2415 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2416 	return ret;
2417 unlock_noconn:
2418 	if (wait)
2419 		iowait_sdma_inc(wait);
2420 	tx->next_descq_idx = 0;
2421 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2422 	tx->sn = sde->tail_sn++;
2423 	trace_hfi1_sdma_in_sn(sde, tx->sn);
2424 #endif
2425 	spin_lock(&sde->flushlist_lock);
2426 	list_add_tail(&tx->list, &sde->flushlist);
2427 	spin_unlock(&sde->flushlist_lock);
2428 	if (wait) {
2429 		wait->tx_count++;
2430 		wait->count += tx->num_desc;
2431 	}
2432 	schedule_work(&sde->flush_worker);
2433 	ret = -ECOMM;
2434 	goto unlock;
2435 nodesc:
2436 	ret = sdma_check_progress(sde, wait, tx, pkts_sent);
2437 	if (ret == -EAGAIN) {
2438 		ret = 0;
2439 		goto retry;
2440 	}
2441 	sde->descq_full_count++;
2442 	goto unlock;
2443 }
2444 
2445 /**
2446  * sdma_send_txlist() - submit a list of tx req to ring
2447  * @sde: sdma engine to use
2448  * @wait: wait structure to use when full (may be NULL)
2449  * @tx_list: list of sdma_txreqs to submit
2450  * @count: pointer to a u32 which, after return will contain the total number of
2451  *         sdma_txreqs removed from the tx_list. This will include sdma_txreqs
2452  *         whose SDMA descriptors are submitted to the ring and the sdma_txreqs
2453  *         which are added to SDMA engine flush list if the SDMA engine state is
2454  *         not running.
2455  *
2456  * The call submits the list into the ring.
2457  *
2458  * If the iowait structure is non-NULL and not equal to the iowait list
2459  * the unprocessed part of the list  will be appended to the list in wait.
2460  *
2461  * In all cases, the tx_list will be updated so the head of the tx_list is
2462  * the list of descriptors that have yet to be transmitted.
2463  *
2464  * The intent of this call is to provide a more efficient
2465  * way of submitting multiple packets to SDMA while holding the tail
2466  * side locking.
2467  *
2468  * Return:
2469  * 0 - Success,
2470  * -EINVAL - sdma_txreq incomplete, -EBUSY - no space in ring (wait == NULL)
2471  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2472  */
2473 int sdma_send_txlist(struct sdma_engine *sde, struct iowait *wait,
2474 		     struct list_head *tx_list, u32 *count_out)
2475 {
2476 	struct sdma_txreq *tx, *tx_next;
2477 	int ret = 0;
2478 	unsigned long flags;
2479 	u16 tail = INVALID_TAIL;
2480 	u32 submit_count = 0, flush_count = 0, total_count;
2481 
2482 	spin_lock_irqsave(&sde->tail_lock, flags);
2483 retry:
2484 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2485 		tx->wait = wait;
2486 		if (unlikely(!__sdma_running(sde)))
2487 			goto unlock_noconn;
2488 		if (unlikely(tx->num_desc > sde->desc_avail))
2489 			goto nodesc;
2490 		if (unlikely(tx->tlen)) {
2491 			ret = -EINVAL;
2492 			goto update_tail;
2493 		}
2494 		list_del_init(&tx->list);
2495 		tail = submit_tx(sde, tx);
2496 		submit_count++;
2497 		if (tail != INVALID_TAIL &&
2498 		    (submit_count & SDMA_TAIL_UPDATE_THRESH) == 0) {
2499 			sdma_update_tail(sde, tail);
2500 			tail = INVALID_TAIL;
2501 		}
2502 	}
2503 update_tail:
2504 	total_count = submit_count + flush_count;
2505 	if (wait) {
2506 		iowait_sdma_add(wait, total_count);
2507 		iowait_starve_clear(submit_count > 0, wait);
2508 	}
2509 	if (tail != INVALID_TAIL)
2510 		sdma_update_tail(sde, tail);
2511 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2512 	*count_out = total_count;
2513 	return ret;
2514 unlock_noconn:
2515 	spin_lock(&sde->flushlist_lock);
2516 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2517 		tx->wait = wait;
2518 		list_del_init(&tx->list);
2519 		tx->next_descq_idx = 0;
2520 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2521 		tx->sn = sde->tail_sn++;
2522 		trace_hfi1_sdma_in_sn(sde, tx->sn);
2523 #endif
2524 		list_add_tail(&tx->list, &sde->flushlist);
2525 		flush_count++;
2526 		if (wait) {
2527 			wait->tx_count++;
2528 			wait->count += tx->num_desc;
2529 		}
2530 	}
2531 	spin_unlock(&sde->flushlist_lock);
2532 	schedule_work(&sde->flush_worker);
2533 	ret = -ECOMM;
2534 	goto update_tail;
2535 nodesc:
2536 	ret = sdma_check_progress(sde, wait, tx, submit_count > 0);
2537 	if (ret == -EAGAIN) {
2538 		ret = 0;
2539 		goto retry;
2540 	}
2541 	sde->descq_full_count++;
2542 	goto update_tail;
2543 }
2544 
2545 static void sdma_process_event(struct sdma_engine *sde, enum sdma_events event)
2546 {
2547 	unsigned long flags;
2548 
2549 	spin_lock_irqsave(&sde->tail_lock, flags);
2550 	write_seqlock(&sde->head_lock);
2551 
2552 	__sdma_process_event(sde, event);
2553 
2554 	if (sde->state.current_state == sdma_state_s99_running)
2555 		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
2556 
2557 	write_sequnlock(&sde->head_lock);
2558 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2559 }
2560 
2561 static void __sdma_process_event(struct sdma_engine *sde,
2562 				 enum sdma_events event)
2563 {
2564 	struct sdma_state *ss = &sde->state;
2565 	int need_progress = 0;
2566 
2567 	/* CONFIG SDMA temporary */
2568 #ifdef CONFIG_SDMA_VERBOSITY
2569 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) [%s] %s\n", sde->this_idx,
2570 		   sdma_state_names[ss->current_state],
2571 		   sdma_event_names[event]);
2572 #endif
2573 
2574 	switch (ss->current_state) {
2575 	case sdma_state_s00_hw_down:
2576 		switch (event) {
2577 		case sdma_event_e00_go_hw_down:
2578 			break;
2579 		case sdma_event_e30_go_running:
2580 			/*
2581 			 * If down, but running requested (usually result
2582 			 * of link up, then we need to start up.
2583 			 * This can happen when hw down is requested while
2584 			 * bringing the link up with traffic active on
2585 			 * 7220, e.g.
2586 			 */
2587 			ss->go_s99_running = 1;
2588 			/* fall through -- and start dma engine */
2589 		case sdma_event_e10_go_hw_start:
2590 			/* This reference means the state machine is started */
2591 			sdma_get(&sde->state);
2592 			sdma_set_state(sde,
2593 				       sdma_state_s10_hw_start_up_halt_wait);
2594 			break;
2595 		case sdma_event_e15_hw_halt_done:
2596 			break;
2597 		case sdma_event_e25_hw_clean_up_done:
2598 			break;
2599 		case sdma_event_e40_sw_cleaned:
2600 			sdma_sw_tear_down(sde);
2601 			break;
2602 		case sdma_event_e50_hw_cleaned:
2603 			break;
2604 		case sdma_event_e60_hw_halted:
2605 			break;
2606 		case sdma_event_e70_go_idle:
2607 			break;
2608 		case sdma_event_e80_hw_freeze:
2609 			break;
2610 		case sdma_event_e81_hw_frozen:
2611 			break;
2612 		case sdma_event_e82_hw_unfreeze:
2613 			break;
2614 		case sdma_event_e85_link_down:
2615 			break;
2616 		case sdma_event_e90_sw_halted:
2617 			break;
2618 		}
2619 		break;
2620 
2621 	case sdma_state_s10_hw_start_up_halt_wait:
2622 		switch (event) {
2623 		case sdma_event_e00_go_hw_down:
2624 			sdma_set_state(sde, sdma_state_s00_hw_down);
2625 			sdma_sw_tear_down(sde);
2626 			break;
2627 		case sdma_event_e10_go_hw_start:
2628 			break;
2629 		case sdma_event_e15_hw_halt_done:
2630 			sdma_set_state(sde,
2631 				       sdma_state_s15_hw_start_up_clean_wait);
2632 			sdma_start_hw_clean_up(sde);
2633 			break;
2634 		case sdma_event_e25_hw_clean_up_done:
2635 			break;
2636 		case sdma_event_e30_go_running:
2637 			ss->go_s99_running = 1;
2638 			break;
2639 		case sdma_event_e40_sw_cleaned:
2640 			break;
2641 		case sdma_event_e50_hw_cleaned:
2642 			break;
2643 		case sdma_event_e60_hw_halted:
2644 			schedule_work(&sde->err_halt_worker);
2645 			break;
2646 		case sdma_event_e70_go_idle:
2647 			ss->go_s99_running = 0;
2648 			break;
2649 		case sdma_event_e80_hw_freeze:
2650 			break;
2651 		case sdma_event_e81_hw_frozen:
2652 			break;
2653 		case sdma_event_e82_hw_unfreeze:
2654 			break;
2655 		case sdma_event_e85_link_down:
2656 			break;
2657 		case sdma_event_e90_sw_halted:
2658 			break;
2659 		}
2660 		break;
2661 
2662 	case sdma_state_s15_hw_start_up_clean_wait:
2663 		switch (event) {
2664 		case sdma_event_e00_go_hw_down:
2665 			sdma_set_state(sde, sdma_state_s00_hw_down);
2666 			sdma_sw_tear_down(sde);
2667 			break;
2668 		case sdma_event_e10_go_hw_start:
2669 			break;
2670 		case sdma_event_e15_hw_halt_done:
2671 			break;
2672 		case sdma_event_e25_hw_clean_up_done:
2673 			sdma_hw_start_up(sde);
2674 			sdma_set_state(sde, ss->go_s99_running ?
2675 				       sdma_state_s99_running :
2676 				       sdma_state_s20_idle);
2677 			break;
2678 		case sdma_event_e30_go_running:
2679 			ss->go_s99_running = 1;
2680 			break;
2681 		case sdma_event_e40_sw_cleaned:
2682 			break;
2683 		case sdma_event_e50_hw_cleaned:
2684 			break;
2685 		case sdma_event_e60_hw_halted:
2686 			break;
2687 		case sdma_event_e70_go_idle:
2688 			ss->go_s99_running = 0;
2689 			break;
2690 		case sdma_event_e80_hw_freeze:
2691 			break;
2692 		case sdma_event_e81_hw_frozen:
2693 			break;
2694 		case sdma_event_e82_hw_unfreeze:
2695 			break;
2696 		case sdma_event_e85_link_down:
2697 			break;
2698 		case sdma_event_e90_sw_halted:
2699 			break;
2700 		}
2701 		break;
2702 
2703 	case sdma_state_s20_idle:
2704 		switch (event) {
2705 		case sdma_event_e00_go_hw_down:
2706 			sdma_set_state(sde, sdma_state_s00_hw_down);
2707 			sdma_sw_tear_down(sde);
2708 			break;
2709 		case sdma_event_e10_go_hw_start:
2710 			break;
2711 		case sdma_event_e15_hw_halt_done:
2712 			break;
2713 		case sdma_event_e25_hw_clean_up_done:
2714 			break;
2715 		case sdma_event_e30_go_running:
2716 			sdma_set_state(sde, sdma_state_s99_running);
2717 			ss->go_s99_running = 1;
2718 			break;
2719 		case sdma_event_e40_sw_cleaned:
2720 			break;
2721 		case sdma_event_e50_hw_cleaned:
2722 			break;
2723 		case sdma_event_e60_hw_halted:
2724 			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
2725 			schedule_work(&sde->err_halt_worker);
2726 			break;
2727 		case sdma_event_e70_go_idle:
2728 			break;
2729 		case sdma_event_e85_link_down:
2730 			/* fall through */
2731 		case sdma_event_e80_hw_freeze:
2732 			sdma_set_state(sde, sdma_state_s80_hw_freeze);
2733 			atomic_dec(&sde->dd->sdma_unfreeze_count);
2734 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2735 			break;
2736 		case sdma_event_e81_hw_frozen:
2737 			break;
2738 		case sdma_event_e82_hw_unfreeze:
2739 			break;
2740 		case sdma_event_e90_sw_halted:
2741 			break;
2742 		}
2743 		break;
2744 
2745 	case sdma_state_s30_sw_clean_up_wait:
2746 		switch (event) {
2747 		case sdma_event_e00_go_hw_down:
2748 			sdma_set_state(sde, sdma_state_s00_hw_down);
2749 			break;
2750 		case sdma_event_e10_go_hw_start:
2751 			break;
2752 		case sdma_event_e15_hw_halt_done:
2753 			break;
2754 		case sdma_event_e25_hw_clean_up_done:
2755 			break;
2756 		case sdma_event_e30_go_running:
2757 			ss->go_s99_running = 1;
2758 			break;
2759 		case sdma_event_e40_sw_cleaned:
2760 			sdma_set_state(sde, sdma_state_s40_hw_clean_up_wait);
2761 			sdma_start_hw_clean_up(sde);
2762 			break;
2763 		case sdma_event_e50_hw_cleaned:
2764 			break;
2765 		case sdma_event_e60_hw_halted:
2766 			break;
2767 		case sdma_event_e70_go_idle:
2768 			ss->go_s99_running = 0;
2769 			break;
2770 		case sdma_event_e80_hw_freeze:
2771 			break;
2772 		case sdma_event_e81_hw_frozen:
2773 			break;
2774 		case sdma_event_e82_hw_unfreeze:
2775 			break;
2776 		case sdma_event_e85_link_down:
2777 			ss->go_s99_running = 0;
2778 			break;
2779 		case sdma_event_e90_sw_halted:
2780 			break;
2781 		}
2782 		break;
2783 
2784 	case sdma_state_s40_hw_clean_up_wait:
2785 		switch (event) {
2786 		case sdma_event_e00_go_hw_down:
2787 			sdma_set_state(sde, sdma_state_s00_hw_down);
2788 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2789 			break;
2790 		case sdma_event_e10_go_hw_start:
2791 			break;
2792 		case sdma_event_e15_hw_halt_done:
2793 			break;
2794 		case sdma_event_e25_hw_clean_up_done:
2795 			sdma_hw_start_up(sde);
2796 			sdma_set_state(sde, ss->go_s99_running ?
2797 				       sdma_state_s99_running :
2798 				       sdma_state_s20_idle);
2799 			break;
2800 		case sdma_event_e30_go_running:
2801 			ss->go_s99_running = 1;
2802 			break;
2803 		case sdma_event_e40_sw_cleaned:
2804 			break;
2805 		case sdma_event_e50_hw_cleaned:
2806 			break;
2807 		case sdma_event_e60_hw_halted:
2808 			break;
2809 		case sdma_event_e70_go_idle:
2810 			ss->go_s99_running = 0;
2811 			break;
2812 		case sdma_event_e80_hw_freeze:
2813 			break;
2814 		case sdma_event_e81_hw_frozen:
2815 			break;
2816 		case sdma_event_e82_hw_unfreeze:
2817 			break;
2818 		case sdma_event_e85_link_down:
2819 			ss->go_s99_running = 0;
2820 			break;
2821 		case sdma_event_e90_sw_halted:
2822 			break;
2823 		}
2824 		break;
2825 
2826 	case sdma_state_s50_hw_halt_wait:
2827 		switch (event) {
2828 		case sdma_event_e00_go_hw_down:
2829 			sdma_set_state(sde, sdma_state_s00_hw_down);
2830 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2831 			break;
2832 		case sdma_event_e10_go_hw_start:
2833 			break;
2834 		case sdma_event_e15_hw_halt_done:
2835 			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2836 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2837 			break;
2838 		case sdma_event_e25_hw_clean_up_done:
2839 			break;
2840 		case sdma_event_e30_go_running:
2841 			ss->go_s99_running = 1;
2842 			break;
2843 		case sdma_event_e40_sw_cleaned:
2844 			break;
2845 		case sdma_event_e50_hw_cleaned:
2846 			break;
2847 		case sdma_event_e60_hw_halted:
2848 			schedule_work(&sde->err_halt_worker);
2849 			break;
2850 		case sdma_event_e70_go_idle:
2851 			ss->go_s99_running = 0;
2852 			break;
2853 		case sdma_event_e80_hw_freeze:
2854 			break;
2855 		case sdma_event_e81_hw_frozen:
2856 			break;
2857 		case sdma_event_e82_hw_unfreeze:
2858 			break;
2859 		case sdma_event_e85_link_down:
2860 			ss->go_s99_running = 0;
2861 			break;
2862 		case sdma_event_e90_sw_halted:
2863 			break;
2864 		}
2865 		break;
2866 
2867 	case sdma_state_s60_idle_halt_wait:
2868 		switch (event) {
2869 		case sdma_event_e00_go_hw_down:
2870 			sdma_set_state(sde, sdma_state_s00_hw_down);
2871 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2872 			break;
2873 		case sdma_event_e10_go_hw_start:
2874 			break;
2875 		case sdma_event_e15_hw_halt_done:
2876 			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2877 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2878 			break;
2879 		case sdma_event_e25_hw_clean_up_done:
2880 			break;
2881 		case sdma_event_e30_go_running:
2882 			ss->go_s99_running = 1;
2883 			break;
2884 		case sdma_event_e40_sw_cleaned:
2885 			break;
2886 		case sdma_event_e50_hw_cleaned:
2887 			break;
2888 		case sdma_event_e60_hw_halted:
2889 			schedule_work(&sde->err_halt_worker);
2890 			break;
2891 		case sdma_event_e70_go_idle:
2892 			ss->go_s99_running = 0;
2893 			break;
2894 		case sdma_event_e80_hw_freeze:
2895 			break;
2896 		case sdma_event_e81_hw_frozen:
2897 			break;
2898 		case sdma_event_e82_hw_unfreeze:
2899 			break;
2900 		case sdma_event_e85_link_down:
2901 			break;
2902 		case sdma_event_e90_sw_halted:
2903 			break;
2904 		}
2905 		break;
2906 
2907 	case sdma_state_s80_hw_freeze:
2908 		switch (event) {
2909 		case sdma_event_e00_go_hw_down:
2910 			sdma_set_state(sde, sdma_state_s00_hw_down);
2911 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2912 			break;
2913 		case sdma_event_e10_go_hw_start:
2914 			break;
2915 		case sdma_event_e15_hw_halt_done:
2916 			break;
2917 		case sdma_event_e25_hw_clean_up_done:
2918 			break;
2919 		case sdma_event_e30_go_running:
2920 			ss->go_s99_running = 1;
2921 			break;
2922 		case sdma_event_e40_sw_cleaned:
2923 			break;
2924 		case sdma_event_e50_hw_cleaned:
2925 			break;
2926 		case sdma_event_e60_hw_halted:
2927 			break;
2928 		case sdma_event_e70_go_idle:
2929 			ss->go_s99_running = 0;
2930 			break;
2931 		case sdma_event_e80_hw_freeze:
2932 			break;
2933 		case sdma_event_e81_hw_frozen:
2934 			sdma_set_state(sde, sdma_state_s82_freeze_sw_clean);
2935 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2936 			break;
2937 		case sdma_event_e82_hw_unfreeze:
2938 			break;
2939 		case sdma_event_e85_link_down:
2940 			break;
2941 		case sdma_event_e90_sw_halted:
2942 			break;
2943 		}
2944 		break;
2945 
2946 	case sdma_state_s82_freeze_sw_clean:
2947 		switch (event) {
2948 		case sdma_event_e00_go_hw_down:
2949 			sdma_set_state(sde, sdma_state_s00_hw_down);
2950 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2951 			break;
2952 		case sdma_event_e10_go_hw_start:
2953 			break;
2954 		case sdma_event_e15_hw_halt_done:
2955 			break;
2956 		case sdma_event_e25_hw_clean_up_done:
2957 			break;
2958 		case sdma_event_e30_go_running:
2959 			ss->go_s99_running = 1;
2960 			break;
2961 		case sdma_event_e40_sw_cleaned:
2962 			/* notify caller this engine is done cleaning */
2963 			atomic_dec(&sde->dd->sdma_unfreeze_count);
2964 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2965 			break;
2966 		case sdma_event_e50_hw_cleaned:
2967 			break;
2968 		case sdma_event_e60_hw_halted:
2969 			break;
2970 		case sdma_event_e70_go_idle:
2971 			ss->go_s99_running = 0;
2972 			break;
2973 		case sdma_event_e80_hw_freeze:
2974 			break;
2975 		case sdma_event_e81_hw_frozen:
2976 			break;
2977 		case sdma_event_e82_hw_unfreeze:
2978 			sdma_hw_start_up(sde);
2979 			sdma_set_state(sde, ss->go_s99_running ?
2980 				       sdma_state_s99_running :
2981 				       sdma_state_s20_idle);
2982 			break;
2983 		case sdma_event_e85_link_down:
2984 			break;
2985 		case sdma_event_e90_sw_halted:
2986 			break;
2987 		}
2988 		break;
2989 
2990 	case sdma_state_s99_running:
2991 		switch (event) {
2992 		case sdma_event_e00_go_hw_down:
2993 			sdma_set_state(sde, sdma_state_s00_hw_down);
2994 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2995 			break;
2996 		case sdma_event_e10_go_hw_start:
2997 			break;
2998 		case sdma_event_e15_hw_halt_done:
2999 			break;
3000 		case sdma_event_e25_hw_clean_up_done:
3001 			break;
3002 		case sdma_event_e30_go_running:
3003 			break;
3004 		case sdma_event_e40_sw_cleaned:
3005 			break;
3006 		case sdma_event_e50_hw_cleaned:
3007 			break;
3008 		case sdma_event_e60_hw_halted:
3009 			need_progress = 1;
3010 			sdma_err_progress_check_schedule(sde);
3011 			/* fall through */
3012 		case sdma_event_e90_sw_halted:
3013 			/*
3014 			* SW initiated halt does not perform engines
3015 			* progress check
3016 			*/
3017 			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
3018 			schedule_work(&sde->err_halt_worker);
3019 			break;
3020 		case sdma_event_e70_go_idle:
3021 			sdma_set_state(sde, sdma_state_s60_idle_halt_wait);
3022 			break;
3023 		case sdma_event_e85_link_down:
3024 			ss->go_s99_running = 0;
3025 			/* fall through */
3026 		case sdma_event_e80_hw_freeze:
3027 			sdma_set_state(sde, sdma_state_s80_hw_freeze);
3028 			atomic_dec(&sde->dd->sdma_unfreeze_count);
3029 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
3030 			break;
3031 		case sdma_event_e81_hw_frozen:
3032 			break;
3033 		case sdma_event_e82_hw_unfreeze:
3034 			break;
3035 		}
3036 		break;
3037 	}
3038 
3039 	ss->last_event = event;
3040 	if (need_progress)
3041 		sdma_make_progress(sde, 0);
3042 }
3043 
3044 /*
3045  * _extend_sdma_tx_descs() - helper to extend txreq
3046  *
3047  * This is called once the initial nominal allocation
3048  * of descriptors in the sdma_txreq is exhausted.
3049  *
3050  * The code will bump the allocation up to the max
3051  * of MAX_DESC (64) descriptors. There doesn't seem
3052  * much point in an interim step. The last descriptor
3053  * is reserved for coalesce buffer in order to support
3054  * cases where input packet has >MAX_DESC iovecs.
3055  *
3056  */
3057 static int _extend_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3058 {
3059 	int i;
3060 
3061 	/* Handle last descriptor */
3062 	if (unlikely((tx->num_desc == (MAX_DESC - 1)))) {
3063 		/* if tlen is 0, it is for padding, release last descriptor */
3064 		if (!tx->tlen) {
3065 			tx->desc_limit = MAX_DESC;
3066 		} else if (!tx->coalesce_buf) {
3067 			/* allocate coalesce buffer with space for padding */
3068 			tx->coalesce_buf = kmalloc(tx->tlen + sizeof(u32),
3069 						   GFP_ATOMIC);
3070 			if (!tx->coalesce_buf)
3071 				goto enomem;
3072 			tx->coalesce_idx = 0;
3073 		}
3074 		return 0;
3075 	}
3076 
3077 	if (unlikely(tx->num_desc == MAX_DESC))
3078 		goto enomem;
3079 
3080 	tx->descp = kmalloc_array(
3081 			MAX_DESC,
3082 			sizeof(struct sdma_desc),
3083 			GFP_ATOMIC);
3084 	if (!tx->descp)
3085 		goto enomem;
3086 
3087 	/* reserve last descriptor for coalescing */
3088 	tx->desc_limit = MAX_DESC - 1;
3089 	/* copy ones already built */
3090 	for (i = 0; i < tx->num_desc; i++)
3091 		tx->descp[i] = tx->descs[i];
3092 	return 0;
3093 enomem:
3094 	__sdma_txclean(dd, tx);
3095 	return -ENOMEM;
3096 }
3097 
3098 /*
3099  * ext_coal_sdma_tx_descs() - extend or coalesce sdma tx descriptors
3100  *
3101  * This is called once the initial nominal allocation of descriptors
3102  * in the sdma_txreq is exhausted.
3103  *
3104  * This function calls _extend_sdma_tx_descs to extend or allocate
3105  * coalesce buffer. If there is a allocated coalesce buffer, it will
3106  * copy the input packet data into the coalesce buffer. It also adds
3107  * coalesce buffer descriptor once when whole packet is received.
3108  *
3109  * Return:
3110  * <0 - error
3111  * 0 - coalescing, don't populate descriptor
3112  * 1 - continue with populating descriptor
3113  */
3114 int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
3115 			   int type, void *kvaddr, struct page *page,
3116 			   unsigned long offset, u16 len)
3117 {
3118 	int pad_len, rval;
3119 	dma_addr_t addr;
3120 
3121 	rval = _extend_sdma_tx_descs(dd, tx);
3122 	if (rval) {
3123 		__sdma_txclean(dd, tx);
3124 		return rval;
3125 	}
3126 
3127 	/* If coalesce buffer is allocated, copy data into it */
3128 	if (tx->coalesce_buf) {
3129 		if (type == SDMA_MAP_NONE) {
3130 			__sdma_txclean(dd, tx);
3131 			return -EINVAL;
3132 		}
3133 
3134 		if (type == SDMA_MAP_PAGE) {
3135 			kvaddr = kmap(page);
3136 			kvaddr += offset;
3137 		} else if (WARN_ON(!kvaddr)) {
3138 			__sdma_txclean(dd, tx);
3139 			return -EINVAL;
3140 		}
3141 
3142 		memcpy(tx->coalesce_buf + tx->coalesce_idx, kvaddr, len);
3143 		tx->coalesce_idx += len;
3144 		if (type == SDMA_MAP_PAGE)
3145 			kunmap(page);
3146 
3147 		/* If there is more data, return */
3148 		if (tx->tlen - tx->coalesce_idx)
3149 			return 0;
3150 
3151 		/* Whole packet is received; add any padding */
3152 		pad_len = tx->packet_len & (sizeof(u32) - 1);
3153 		if (pad_len) {
3154 			pad_len = sizeof(u32) - pad_len;
3155 			memset(tx->coalesce_buf + tx->coalesce_idx, 0, pad_len);
3156 			/* padding is taken care of for coalescing case */
3157 			tx->packet_len += pad_len;
3158 			tx->tlen += pad_len;
3159 		}
3160 
3161 		/* dma map the coalesce buffer */
3162 		addr = dma_map_single(&dd->pcidev->dev,
3163 				      tx->coalesce_buf,
3164 				      tx->tlen,
3165 				      DMA_TO_DEVICE);
3166 
3167 		if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
3168 			__sdma_txclean(dd, tx);
3169 			return -ENOSPC;
3170 		}
3171 
3172 		/* Add descriptor for coalesce buffer */
3173 		tx->desc_limit = MAX_DESC;
3174 		return _sdma_txadd_daddr(dd, SDMA_MAP_SINGLE, tx,
3175 					 addr, tx->tlen);
3176 	}
3177 
3178 	return 1;
3179 }
3180 
3181 /* Update sdes when the lmc changes */
3182 void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid)
3183 {
3184 	struct sdma_engine *sde;
3185 	int i;
3186 	u64 sreg;
3187 
3188 	sreg = ((mask & SD(CHECK_SLID_MASK_MASK)) <<
3189 		SD(CHECK_SLID_MASK_SHIFT)) |
3190 		(((lid & mask) & SD(CHECK_SLID_VALUE_MASK)) <<
3191 		SD(CHECK_SLID_VALUE_SHIFT));
3192 
3193 	for (i = 0; i < dd->num_sdma; i++) {
3194 		hfi1_cdbg(LINKVERB, "SendDmaEngine[%d].SLID_CHECK = 0x%x",
3195 			  i, (u32)sreg);
3196 		sde = &dd->per_sdma[i];
3197 		write_sde_csr(sde, SD(CHECK_SLID), sreg);
3198 	}
3199 }
3200 
3201 /* tx not dword sized - pad */
3202 int _pad_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3203 {
3204 	int rval = 0;
3205 
3206 	tx->num_desc++;
3207 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
3208 		rval = _extend_sdma_tx_descs(dd, tx);
3209 		if (rval) {
3210 			__sdma_txclean(dd, tx);
3211 			return rval;
3212 		}
3213 	}
3214 	/* finish the one just added */
3215 	make_tx_sdma_desc(
3216 		tx,
3217 		SDMA_MAP_NONE,
3218 		dd->sdma_pad_phys,
3219 		sizeof(u32) - (tx->packet_len & (sizeof(u32) - 1)));
3220 	_sdma_close_tx(dd, tx);
3221 	return rval;
3222 }
3223 
3224 /*
3225  * Add ahg to the sdma_txreq
3226  *
3227  * The logic will consume up to 3
3228  * descriptors at the beginning of
3229  * sdma_txreq.
3230  */
3231 void _sdma_txreq_ahgadd(
3232 	struct sdma_txreq *tx,
3233 	u8 num_ahg,
3234 	u8 ahg_entry,
3235 	u32 *ahg,
3236 	u8 ahg_hlen)
3237 {
3238 	u32 i, shift = 0, desc = 0;
3239 	u8 mode;
3240 
3241 	WARN_ON_ONCE(num_ahg > 9 || (ahg_hlen & 3) || ahg_hlen == 4);
3242 	/* compute mode */
3243 	if (num_ahg == 1)
3244 		mode = SDMA_AHG_APPLY_UPDATE1;
3245 	else if (num_ahg <= 5)
3246 		mode = SDMA_AHG_APPLY_UPDATE2;
3247 	else
3248 		mode = SDMA_AHG_APPLY_UPDATE3;
3249 	tx->num_desc++;
3250 	/* initialize to consumed descriptors to zero */
3251 	switch (mode) {
3252 	case SDMA_AHG_APPLY_UPDATE3:
3253 		tx->num_desc++;
3254 		tx->descs[2].qw[0] = 0;
3255 		tx->descs[2].qw[1] = 0;
3256 		/* FALLTHROUGH */
3257 	case SDMA_AHG_APPLY_UPDATE2:
3258 		tx->num_desc++;
3259 		tx->descs[1].qw[0] = 0;
3260 		tx->descs[1].qw[1] = 0;
3261 		break;
3262 	}
3263 	ahg_hlen >>= 2;
3264 	tx->descs[0].qw[1] |=
3265 		(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
3266 			<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
3267 		(((u64)ahg_hlen & SDMA_DESC1_HEADER_DWS_MASK)
3268 			<< SDMA_DESC1_HEADER_DWS_SHIFT) |
3269 		(((u64)mode & SDMA_DESC1_HEADER_MODE_MASK)
3270 			<< SDMA_DESC1_HEADER_MODE_SHIFT) |
3271 		(((u64)ahg[0] & SDMA_DESC1_HEADER_UPDATE1_MASK)
3272 			<< SDMA_DESC1_HEADER_UPDATE1_SHIFT);
3273 	for (i = 0; i < (num_ahg - 1); i++) {
3274 		if (!shift && !(i & 2))
3275 			desc++;
3276 		tx->descs[desc].qw[!!(i & 2)] |=
3277 			(((u64)ahg[i + 1])
3278 				<< shift);
3279 		shift = (shift + 32) & 63;
3280 	}
3281 }
3282 
3283 /**
3284  * sdma_ahg_alloc - allocate an AHG entry
3285  * @sde: engine to allocate from
3286  *
3287  * Return:
3288  * 0-31 when successful, -EOPNOTSUPP if AHG is not enabled,
3289  * -ENOSPC if an entry is not available
3290  */
3291 int sdma_ahg_alloc(struct sdma_engine *sde)
3292 {
3293 	int nr;
3294 	int oldbit;
3295 
3296 	if (!sde) {
3297 		trace_hfi1_ahg_allocate(sde, -EINVAL);
3298 		return -EINVAL;
3299 	}
3300 	while (1) {
3301 		nr = ffz(READ_ONCE(sde->ahg_bits));
3302 		if (nr > 31) {
3303 			trace_hfi1_ahg_allocate(sde, -ENOSPC);
3304 			return -ENOSPC;
3305 		}
3306 		oldbit = test_and_set_bit(nr, &sde->ahg_bits);
3307 		if (!oldbit)
3308 			break;
3309 		cpu_relax();
3310 	}
3311 	trace_hfi1_ahg_allocate(sde, nr);
3312 	return nr;
3313 }
3314 
3315 /**
3316  * sdma_ahg_free - free an AHG entry
3317  * @sde: engine to return AHG entry
3318  * @ahg_index: index to free
3319  *
3320  * This routine frees the indicate AHG entry.
3321  */
3322 void sdma_ahg_free(struct sdma_engine *sde, int ahg_index)
3323 {
3324 	if (!sde)
3325 		return;
3326 	trace_hfi1_ahg_deallocate(sde, ahg_index);
3327 	if (ahg_index < 0 || ahg_index > 31)
3328 		return;
3329 	clear_bit(ahg_index, &sde->ahg_bits);
3330 }
3331 
3332 /*
3333  * SPC freeze handling for SDMA engines.  Called when the driver knows
3334  * the SPC is going into a freeze but before the freeze is fully
3335  * settled.  Generally an error interrupt.
3336  *
3337  * This event will pull the engine out of running so no more entries can be
3338  * added to the engine's queue.
3339  */
3340 void sdma_freeze_notify(struct hfi1_devdata *dd, int link_down)
3341 {
3342 	int i;
3343 	enum sdma_events event = link_down ? sdma_event_e85_link_down :
3344 					     sdma_event_e80_hw_freeze;
3345 
3346 	/* set up the wait but do not wait here */
3347 	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3348 
3349 	/* tell all engines to stop running and wait */
3350 	for (i = 0; i < dd->num_sdma; i++)
3351 		sdma_process_event(&dd->per_sdma[i], event);
3352 
3353 	/* sdma_freeze() will wait for all engines to have stopped */
3354 }
3355 
3356 /*
3357  * SPC freeze handling for SDMA engines.  Called when the driver knows
3358  * the SPC is fully frozen.
3359  */
3360 void sdma_freeze(struct hfi1_devdata *dd)
3361 {
3362 	int i;
3363 	int ret;
3364 
3365 	/*
3366 	 * Make sure all engines have moved out of the running state before
3367 	 * continuing.
3368 	 */
3369 	ret = wait_event_interruptible(dd->sdma_unfreeze_wq,
3370 				       atomic_read(&dd->sdma_unfreeze_count) <=
3371 				       0);
3372 	/* interrupted or count is negative, then unloading - just exit */
3373 	if (ret || atomic_read(&dd->sdma_unfreeze_count) < 0)
3374 		return;
3375 
3376 	/* set up the count for the next wait */
3377 	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3378 
3379 	/* tell all engines that the SPC is frozen, they can start cleaning */
3380 	for (i = 0; i < dd->num_sdma; i++)
3381 		sdma_process_event(&dd->per_sdma[i], sdma_event_e81_hw_frozen);
3382 
3383 	/*
3384 	 * Wait for everyone to finish software clean before exiting.  The
3385 	 * software clean will read engine CSRs, so must be completed before
3386 	 * the next step, which will clear the engine CSRs.
3387 	 */
3388 	(void)wait_event_interruptible(dd->sdma_unfreeze_wq,
3389 				atomic_read(&dd->sdma_unfreeze_count) <= 0);
3390 	/* no need to check results - done no matter what */
3391 }
3392 
3393 /*
3394  * SPC freeze handling for the SDMA engines.  Called after the SPC is unfrozen.
3395  *
3396  * The SPC freeze acts like a SDMA halt and a hardware clean combined.  All
3397  * that is left is a software clean.  We could do it after the SPC is fully
3398  * frozen, but then we'd have to add another state to wait for the unfreeze.
3399  * Instead, just defer the software clean until the unfreeze step.
3400  */
3401 void sdma_unfreeze(struct hfi1_devdata *dd)
3402 {
3403 	int i;
3404 
3405 	/* tell all engines start freeze clean up */
3406 	for (i = 0; i < dd->num_sdma; i++)
3407 		sdma_process_event(&dd->per_sdma[i],
3408 				   sdma_event_e82_hw_unfreeze);
3409 }
3410 
3411 /**
3412  * _sdma_engine_progress_schedule() - schedule progress on engine
3413  * @sde: sdma_engine to schedule progress
3414  *
3415  */
3416 void _sdma_engine_progress_schedule(
3417 	struct sdma_engine *sde)
3418 {
3419 	trace_hfi1_sdma_engine_progress(sde, sde->progress_mask);
3420 	/* assume we have selected a good cpu */
3421 	write_csr(sde->dd,
3422 		  CCE_INT_FORCE + (8 * (IS_SDMA_START / 64)),
3423 		  sde->progress_mask);
3424 }
3425