xref: /openbmc/linux/drivers/infiniband/hw/hfi1/sdma.c (revision d623f60d)
1 /*
2  * Copyright(c) 2015 - 2018 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include <linux/spinlock.h>
49 #include <linux/seqlock.h>
50 #include <linux/netdevice.h>
51 #include <linux/moduleparam.h>
52 #include <linux/bitops.h>
53 #include <linux/timer.h>
54 #include <linux/vmalloc.h>
55 #include <linux/highmem.h>
56 
57 #include "hfi.h"
58 #include "common.h"
59 #include "qp.h"
60 #include "sdma.h"
61 #include "iowait.h"
62 #include "trace.h"
63 
64 /* must be a power of 2 >= 64 <= 32768 */
65 #define SDMA_DESCQ_CNT 2048
66 #define SDMA_DESC_INTR 64
67 #define INVALID_TAIL 0xffff
68 
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 	struct sdma_rht_node *rht_node;
927 
928 	vl = sdma_engine_get_vl(sde);
929 	if (unlikely(vl < 0 || vl >= ARRAY_SIZE(rht_node->map)))
930 		return -EINVAL;
931 
932 	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
933 	if (!ret)
934 		return -ENOMEM;
935 
936 	ret = zalloc_cpumask_var(&new_mask, GFP_KERNEL);
937 	if (!ret) {
938 		free_cpumask_var(mask);
939 		return -ENOMEM;
940 	}
941 	ret = cpulist_parse(buf, mask);
942 	if (ret)
943 		goto out_free;
944 
945 	if (!cpumask_subset(mask, cpu_online_mask)) {
946 		dd_dev_warn(sde->dd, "Invalid CPU mask\n");
947 		ret = -EINVAL;
948 		goto out_free;
949 	}
950 
951 	sz = sizeof(struct sdma_rht_map_elem) +
952 			(TXE_NUM_SDMA_ENGINES * sizeof(struct sdma_engine *));
953 
954 	mutex_lock(&process_to_sde_mutex);
955 
956 	for_each_cpu(cpu, mask) {
957 		/* Check if we have this already mapped */
958 		if (cpumask_test_cpu(cpu, &sde->cpu_mask)) {
959 			cpumask_set_cpu(cpu, new_mask);
960 			continue;
961 		}
962 
963 		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
964 						  sdma_rht_params);
965 		if (!rht_node) {
966 			rht_node = kzalloc(sizeof(*rht_node), GFP_KERNEL);
967 			if (!rht_node) {
968 				ret = -ENOMEM;
969 				goto out;
970 			}
971 
972 			rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
973 			if (!rht_node->map[vl]) {
974 				kfree(rht_node);
975 				ret = -ENOMEM;
976 				goto out;
977 			}
978 			rht_node->cpu_id = cpu;
979 			rht_node->map[vl]->mask = 0;
980 			rht_node->map[vl]->ctr = 1;
981 			rht_node->map[vl]->sde[0] = sde;
982 
983 			ret = rhashtable_insert_fast(dd->sdma_rht,
984 						     &rht_node->node,
985 						     sdma_rht_params);
986 			if (ret) {
987 				kfree(rht_node->map[vl]);
988 				kfree(rht_node);
989 				dd_dev_err(sde->dd, "Failed to set process to sde affinity for cpu %lu\n",
990 					   cpu);
991 				goto out;
992 			}
993 
994 		} else {
995 			int ctr, pow;
996 
997 			/* Add new user mappings */
998 			if (!rht_node->map[vl])
999 				rht_node->map[vl] = kzalloc(sz, GFP_KERNEL);
1000 
1001 			if (!rht_node->map[vl]) {
1002 				ret = -ENOMEM;
1003 				goto out;
1004 			}
1005 
1006 			rht_node->map[vl]->ctr++;
1007 			ctr = rht_node->map[vl]->ctr;
1008 			rht_node->map[vl]->sde[ctr - 1] = sde;
1009 			pow = roundup_pow_of_two(ctr);
1010 			rht_node->map[vl]->mask = pow - 1;
1011 
1012 			/* Populate the sde map table */
1013 			sdma_populate_sde_map(rht_node->map[vl]);
1014 		}
1015 		cpumask_set_cpu(cpu, new_mask);
1016 	}
1017 
1018 	/* Clean up old mappings */
1019 	for_each_cpu(cpu, cpu_online_mask) {
1020 		struct sdma_rht_node *rht_node;
1021 
1022 		/* Don't cleanup sdes that are set in the new mask */
1023 		if (cpumask_test_cpu(cpu, mask))
1024 			continue;
1025 
1026 		rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpu,
1027 						  sdma_rht_params);
1028 		if (rht_node) {
1029 			bool empty = true;
1030 			int i;
1031 
1032 			/* Remove mappings for old sde */
1033 			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1034 				if (rht_node->map[i])
1035 					sdma_cleanup_sde_map(rht_node->map[i],
1036 							     sde);
1037 
1038 			/* Free empty hash table entries */
1039 			for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1040 				if (!rht_node->map[i])
1041 					continue;
1042 
1043 				if (rht_node->map[i]->ctr) {
1044 					empty = false;
1045 					break;
1046 				}
1047 			}
1048 
1049 			if (empty) {
1050 				ret = rhashtable_remove_fast(dd->sdma_rht,
1051 							     &rht_node->node,
1052 							     sdma_rht_params);
1053 				WARN_ON(ret);
1054 
1055 				for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1056 					kfree(rht_node->map[i]);
1057 
1058 				kfree(rht_node);
1059 			}
1060 		}
1061 	}
1062 
1063 	cpumask_copy(&sde->cpu_mask, new_mask);
1064 out:
1065 	mutex_unlock(&process_to_sde_mutex);
1066 out_free:
1067 	free_cpumask_var(mask);
1068 	free_cpumask_var(new_mask);
1069 	return ret ? : strnlen(buf, PAGE_SIZE);
1070 }
1071 
1072 ssize_t sdma_get_cpu_to_sde_map(struct sdma_engine *sde, char *buf)
1073 {
1074 	mutex_lock(&process_to_sde_mutex);
1075 	if (cpumask_empty(&sde->cpu_mask))
1076 		snprintf(buf, PAGE_SIZE, "%s\n", "empty");
1077 	else
1078 		cpumap_print_to_pagebuf(true, buf, &sde->cpu_mask);
1079 	mutex_unlock(&process_to_sde_mutex);
1080 	return strnlen(buf, PAGE_SIZE);
1081 }
1082 
1083 static void sdma_rht_free(void *ptr, void *arg)
1084 {
1085 	struct sdma_rht_node *rht_node = ptr;
1086 	int i;
1087 
1088 	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++)
1089 		kfree(rht_node->map[i]);
1090 
1091 	kfree(rht_node);
1092 }
1093 
1094 /**
1095  * sdma_seqfile_dump_cpu_list() - debugfs dump the cpu to sdma mappings
1096  * @s: seq file
1097  * @dd: hfi1_devdata
1098  * @cpuid: cpu id
1099  *
1100  * This routine dumps the process to sde mappings per cpu
1101  */
1102 void sdma_seqfile_dump_cpu_list(struct seq_file *s,
1103 				struct hfi1_devdata *dd,
1104 				unsigned long cpuid)
1105 {
1106 	struct sdma_rht_node *rht_node;
1107 	int i, j;
1108 
1109 	rht_node = rhashtable_lookup_fast(dd->sdma_rht, &cpuid,
1110 					  sdma_rht_params);
1111 	if (!rht_node)
1112 		return;
1113 
1114 	seq_printf(s, "cpu%3lu: ", cpuid);
1115 	for (i = 0; i < HFI1_MAX_VLS_SUPPORTED; i++) {
1116 		if (!rht_node->map[i] || !rht_node->map[i]->ctr)
1117 			continue;
1118 
1119 		seq_printf(s, " vl%d: [", i);
1120 
1121 		for (j = 0; j < rht_node->map[i]->ctr; j++) {
1122 			if (!rht_node->map[i]->sde[j])
1123 				continue;
1124 
1125 			if (j > 0)
1126 				seq_puts(s, ",");
1127 
1128 			seq_printf(s, " sdma%2d",
1129 				   rht_node->map[i]->sde[j]->this_idx);
1130 		}
1131 		seq_puts(s, " ]");
1132 	}
1133 
1134 	seq_puts(s, "\n");
1135 }
1136 
1137 /*
1138  * Free the indicated map struct
1139  */
1140 static void sdma_map_free(struct sdma_vl_map *m)
1141 {
1142 	int i;
1143 
1144 	for (i = 0; m && i < m->actual_vls; i++)
1145 		kfree(m->map[i]);
1146 	kfree(m);
1147 }
1148 
1149 /*
1150  * Handle RCU callback
1151  */
1152 static void sdma_map_rcu_callback(struct rcu_head *list)
1153 {
1154 	struct sdma_vl_map *m = container_of(list, struct sdma_vl_map, list);
1155 
1156 	sdma_map_free(m);
1157 }
1158 
1159 /**
1160  * sdma_map_init - called when # vls change
1161  * @dd: hfi1_devdata
1162  * @port: port number
1163  * @num_vls: number of vls
1164  * @vl_engines: per vl engine mapping (optional)
1165  *
1166  * This routine changes the mapping based on the number of vls.
1167  *
1168  * vl_engines is used to specify a non-uniform vl/engine loading. NULL
1169  * implies auto computing the loading and giving each VLs a uniform
1170  * distribution of engines per VL.
1171  *
1172  * The auto algorithm computes the sde_per_vl and the number of extra
1173  * engines.  Any extra engines are added from the last VL on down.
1174  *
1175  * rcu locking is used here to control access to the mapping fields.
1176  *
1177  * If either the num_vls or num_sdma are non-power of 2, the array sizes
1178  * in the struct sdma_vl_map and the struct sdma_map_elem are rounded
1179  * up to the next highest power of 2 and the first entry is reused
1180  * in a round robin fashion.
1181  *
1182  * If an error occurs the map change is not done and the mapping is
1183  * not changed.
1184  *
1185  */
1186 int sdma_map_init(struct hfi1_devdata *dd, u8 port, u8 num_vls, u8 *vl_engines)
1187 {
1188 	int i, j;
1189 	int extra, sde_per_vl;
1190 	int engine = 0;
1191 	u8 lvl_engines[OPA_MAX_VLS];
1192 	struct sdma_vl_map *oldmap, *newmap;
1193 
1194 	if (!(dd->flags & HFI1_HAS_SEND_DMA))
1195 		return 0;
1196 
1197 	if (!vl_engines) {
1198 		/* truncate divide */
1199 		sde_per_vl = dd->num_sdma / num_vls;
1200 		/* extras */
1201 		extra = dd->num_sdma % num_vls;
1202 		vl_engines = lvl_engines;
1203 		/* add extras from last vl down */
1204 		for (i = num_vls - 1; i >= 0; i--, extra--)
1205 			vl_engines[i] = sde_per_vl + (extra > 0 ? 1 : 0);
1206 	}
1207 	/* build new map */
1208 	newmap = kzalloc(
1209 		sizeof(struct sdma_vl_map) +
1210 			roundup_pow_of_two(num_vls) *
1211 			sizeof(struct sdma_map_elem *),
1212 		GFP_KERNEL);
1213 	if (!newmap)
1214 		goto bail;
1215 	newmap->actual_vls = num_vls;
1216 	newmap->vls = roundup_pow_of_two(num_vls);
1217 	newmap->mask = (1 << ilog2(newmap->vls)) - 1;
1218 	/* initialize back-map */
1219 	for (i = 0; i < TXE_NUM_SDMA_ENGINES; i++)
1220 		newmap->engine_to_vl[i] = -1;
1221 	for (i = 0; i < newmap->vls; i++) {
1222 		/* save for wrap around */
1223 		int first_engine = engine;
1224 
1225 		if (i < newmap->actual_vls) {
1226 			int sz = roundup_pow_of_two(vl_engines[i]);
1227 
1228 			/* only allocate once */
1229 			newmap->map[i] = kzalloc(
1230 				sizeof(struct sdma_map_elem) +
1231 					sz * sizeof(struct sdma_engine *),
1232 				GFP_KERNEL);
1233 			if (!newmap->map[i])
1234 				goto bail;
1235 			newmap->map[i]->mask = (1 << ilog2(sz)) - 1;
1236 			/* assign engines */
1237 			for (j = 0; j < sz; j++) {
1238 				newmap->map[i]->sde[j] =
1239 					&dd->per_sdma[engine];
1240 				if (++engine >= first_engine + vl_engines[i])
1241 					/* wrap back to first engine */
1242 					engine = first_engine;
1243 			}
1244 			/* assign back-map */
1245 			for (j = 0; j < vl_engines[i]; j++)
1246 				newmap->engine_to_vl[first_engine + j] = i;
1247 		} else {
1248 			/* just re-use entry without allocating */
1249 			newmap->map[i] = newmap->map[i % num_vls];
1250 		}
1251 		engine = first_engine + vl_engines[i];
1252 	}
1253 	/* newmap in hand, save old map */
1254 	spin_lock_irq(&dd->sde_map_lock);
1255 	oldmap = rcu_dereference_protected(dd->sdma_map,
1256 					   lockdep_is_held(&dd->sde_map_lock));
1257 
1258 	/* publish newmap */
1259 	rcu_assign_pointer(dd->sdma_map, newmap);
1260 
1261 	spin_unlock_irq(&dd->sde_map_lock);
1262 	/* success, free any old map after grace period */
1263 	if (oldmap)
1264 		call_rcu(&oldmap->list, sdma_map_rcu_callback);
1265 	return 0;
1266 bail:
1267 	/* free any partial allocation */
1268 	sdma_map_free(newmap);
1269 	return -ENOMEM;
1270 }
1271 
1272 /**
1273  * sdma_clean()  Clean up allocated memory
1274  * @dd:          struct hfi1_devdata
1275  * @num_engines: num sdma engines
1276  *
1277  * This routine can be called regardless of the success of
1278  * sdma_init()
1279  */
1280 void sdma_clean(struct hfi1_devdata *dd, size_t num_engines)
1281 {
1282 	size_t i;
1283 	struct sdma_engine *sde;
1284 
1285 	if (dd->sdma_pad_dma) {
1286 		dma_free_coherent(&dd->pcidev->dev, 4,
1287 				  (void *)dd->sdma_pad_dma,
1288 				  dd->sdma_pad_phys);
1289 		dd->sdma_pad_dma = NULL;
1290 		dd->sdma_pad_phys = 0;
1291 	}
1292 	if (dd->sdma_heads_dma) {
1293 		dma_free_coherent(&dd->pcidev->dev, dd->sdma_heads_size,
1294 				  (void *)dd->sdma_heads_dma,
1295 				  dd->sdma_heads_phys);
1296 		dd->sdma_heads_dma = NULL;
1297 		dd->sdma_heads_phys = 0;
1298 	}
1299 	for (i = 0; dd->per_sdma && i < num_engines; ++i) {
1300 		sde = &dd->per_sdma[i];
1301 
1302 		sde->head_dma = NULL;
1303 		sde->head_phys = 0;
1304 
1305 		if (sde->descq) {
1306 			dma_free_coherent(
1307 				&dd->pcidev->dev,
1308 				sde->descq_cnt * sizeof(u64[2]),
1309 				sde->descq,
1310 				sde->descq_phys
1311 			);
1312 			sde->descq = NULL;
1313 			sde->descq_phys = 0;
1314 		}
1315 		kvfree(sde->tx_ring);
1316 		sde->tx_ring = NULL;
1317 	}
1318 	spin_lock_irq(&dd->sde_map_lock);
1319 	sdma_map_free(rcu_access_pointer(dd->sdma_map));
1320 	RCU_INIT_POINTER(dd->sdma_map, NULL);
1321 	spin_unlock_irq(&dd->sde_map_lock);
1322 	synchronize_rcu();
1323 	kfree(dd->per_sdma);
1324 	dd->per_sdma = NULL;
1325 
1326 	if (dd->sdma_rht) {
1327 		rhashtable_free_and_destroy(dd->sdma_rht, sdma_rht_free, NULL);
1328 		kfree(dd->sdma_rht);
1329 		dd->sdma_rht = NULL;
1330 	}
1331 }
1332 
1333 /**
1334  * sdma_init() - called when device probed
1335  * @dd: hfi1_devdata
1336  * @port: port number (currently only zero)
1337  *
1338  * Initializes each sde and its csrs.
1339  * Interrupts are not required to be enabled.
1340  *
1341  * Returns:
1342  * 0 - success, -errno on failure
1343  */
1344 int sdma_init(struct hfi1_devdata *dd, u8 port)
1345 {
1346 	unsigned this_idx;
1347 	struct sdma_engine *sde;
1348 	struct rhashtable *tmp_sdma_rht;
1349 	u16 descq_cnt;
1350 	void *curr_head;
1351 	struct hfi1_pportdata *ppd = dd->pport + port;
1352 	u32 per_sdma_credits;
1353 	uint idle_cnt = sdma_idle_cnt;
1354 	size_t num_engines = dd->chip_sdma_engines;
1355 	int ret = -ENOMEM;
1356 
1357 	if (!HFI1_CAP_IS_KSET(SDMA)) {
1358 		HFI1_CAP_CLEAR(SDMA_AHG);
1359 		return 0;
1360 	}
1361 	if (mod_num_sdma &&
1362 	    /* can't exceed chip support */
1363 	    mod_num_sdma <= dd->chip_sdma_engines &&
1364 	    /* count must be >= vls */
1365 	    mod_num_sdma >= num_vls)
1366 		num_engines = mod_num_sdma;
1367 
1368 	dd_dev_info(dd, "SDMA mod_num_sdma: %u\n", mod_num_sdma);
1369 	dd_dev_info(dd, "SDMA chip_sdma_engines: %u\n", dd->chip_sdma_engines);
1370 	dd_dev_info(dd, "SDMA chip_sdma_mem_size: %u\n",
1371 		    dd->chip_sdma_mem_size);
1372 
1373 	per_sdma_credits =
1374 		dd->chip_sdma_mem_size / (num_engines * SDMA_BLOCK_SIZE);
1375 
1376 	/* set up freeze waitqueue */
1377 	init_waitqueue_head(&dd->sdma_unfreeze_wq);
1378 	atomic_set(&dd->sdma_unfreeze_count, 0);
1379 
1380 	descq_cnt = sdma_get_descq_cnt();
1381 	dd_dev_info(dd, "SDMA engines %zu descq_cnt %u\n",
1382 		    num_engines, descq_cnt);
1383 
1384 	/* alloc memory for array of send engines */
1385 	dd->per_sdma = kcalloc_node(num_engines, sizeof(*dd->per_sdma),
1386 				    GFP_KERNEL, dd->node);
1387 	if (!dd->per_sdma)
1388 		return ret;
1389 
1390 	idle_cnt = ns_to_cclock(dd, idle_cnt);
1391 	if (idle_cnt)
1392 		dd->default_desc1 =
1393 			SDMA_DESC1_HEAD_TO_HOST_FLAG;
1394 	else
1395 		dd->default_desc1 =
1396 			SDMA_DESC1_INT_REQ_FLAG;
1397 
1398 	if (!sdma_desct_intr)
1399 		sdma_desct_intr = SDMA_DESC_INTR;
1400 
1401 	/* Allocate memory for SendDMA descriptor FIFOs */
1402 	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1403 		sde = &dd->per_sdma[this_idx];
1404 		sde->dd = dd;
1405 		sde->ppd = ppd;
1406 		sde->this_idx = this_idx;
1407 		sde->descq_cnt = descq_cnt;
1408 		sde->desc_avail = sdma_descq_freecnt(sde);
1409 		sde->sdma_shift = ilog2(descq_cnt);
1410 		sde->sdma_mask = (1 << sde->sdma_shift) - 1;
1411 
1412 		/* Create a mask specifically for each interrupt source */
1413 		sde->int_mask = (u64)1 << (0 * TXE_NUM_SDMA_ENGINES +
1414 					   this_idx);
1415 		sde->progress_mask = (u64)1 << (1 * TXE_NUM_SDMA_ENGINES +
1416 						this_idx);
1417 		sde->idle_mask = (u64)1 << (2 * TXE_NUM_SDMA_ENGINES +
1418 					    this_idx);
1419 		/* Create a combined mask to cover all 3 interrupt sources */
1420 		sde->imask = sde->int_mask | sde->progress_mask |
1421 			     sde->idle_mask;
1422 
1423 		spin_lock_init(&sde->tail_lock);
1424 		seqlock_init(&sde->head_lock);
1425 		spin_lock_init(&sde->senddmactrl_lock);
1426 		spin_lock_init(&sde->flushlist_lock);
1427 		/* insure there is always a zero bit */
1428 		sde->ahg_bits = 0xfffffffe00000000ULL;
1429 
1430 		sdma_set_state(sde, sdma_state_s00_hw_down);
1431 
1432 		/* set up reference counting */
1433 		kref_init(&sde->state.kref);
1434 		init_completion(&sde->state.comp);
1435 
1436 		INIT_LIST_HEAD(&sde->flushlist);
1437 		INIT_LIST_HEAD(&sde->dmawait);
1438 
1439 		sde->tail_csr =
1440 			get_kctxt_csr_addr(dd, this_idx, SD(TAIL));
1441 
1442 		tasklet_init(&sde->sdma_hw_clean_up_task, sdma_hw_clean_up_task,
1443 			     (unsigned long)sde);
1444 
1445 		tasklet_init(&sde->sdma_sw_clean_up_task, sdma_sw_clean_up_task,
1446 			     (unsigned long)sde);
1447 		INIT_WORK(&sde->err_halt_worker, sdma_err_halt_wait);
1448 		INIT_WORK(&sde->flush_worker, sdma_field_flush);
1449 
1450 		sde->progress_check_head = 0;
1451 
1452 		timer_setup(&sde->err_progress_check_timer,
1453 			    sdma_err_progress_check, 0);
1454 
1455 		sde->descq = dma_zalloc_coherent(
1456 			&dd->pcidev->dev,
1457 			descq_cnt * sizeof(u64[2]),
1458 			&sde->descq_phys,
1459 			GFP_KERNEL
1460 		);
1461 		if (!sde->descq)
1462 			goto bail;
1463 		sde->tx_ring =
1464 			kvzalloc_node(array_size(descq_cnt,
1465 						 sizeof(struct sdma_txreq *)),
1466 				      GFP_KERNEL, dd->node);
1467 		if (!sde->tx_ring)
1468 			goto bail;
1469 	}
1470 
1471 	dd->sdma_heads_size = L1_CACHE_BYTES * num_engines;
1472 	/* Allocate memory for DMA of head registers to memory */
1473 	dd->sdma_heads_dma = dma_zalloc_coherent(
1474 		&dd->pcidev->dev,
1475 		dd->sdma_heads_size,
1476 		&dd->sdma_heads_phys,
1477 		GFP_KERNEL
1478 	);
1479 	if (!dd->sdma_heads_dma) {
1480 		dd_dev_err(dd, "failed to allocate SendDMA head memory\n");
1481 		goto bail;
1482 	}
1483 
1484 	/* Allocate memory for pad */
1485 	dd->sdma_pad_dma = dma_zalloc_coherent(
1486 		&dd->pcidev->dev,
1487 		sizeof(u32),
1488 		&dd->sdma_pad_phys,
1489 		GFP_KERNEL
1490 	);
1491 	if (!dd->sdma_pad_dma) {
1492 		dd_dev_err(dd, "failed to allocate SendDMA pad memory\n");
1493 		goto bail;
1494 	}
1495 
1496 	/* assign each engine to different cacheline and init registers */
1497 	curr_head = (void *)dd->sdma_heads_dma;
1498 	for (this_idx = 0; this_idx < num_engines; ++this_idx) {
1499 		unsigned long phys_offset;
1500 
1501 		sde = &dd->per_sdma[this_idx];
1502 
1503 		sde->head_dma = curr_head;
1504 		curr_head += L1_CACHE_BYTES;
1505 		phys_offset = (unsigned long)sde->head_dma -
1506 			      (unsigned long)dd->sdma_heads_dma;
1507 		sde->head_phys = dd->sdma_heads_phys + phys_offset;
1508 		init_sdma_regs(sde, per_sdma_credits, idle_cnt);
1509 	}
1510 	dd->flags |= HFI1_HAS_SEND_DMA;
1511 	dd->flags |= idle_cnt ? HFI1_HAS_SDMA_TIMEOUT : 0;
1512 	dd->num_sdma = num_engines;
1513 	ret = sdma_map_init(dd, port, ppd->vls_operational, NULL);
1514 	if (ret < 0)
1515 		goto bail;
1516 
1517 	tmp_sdma_rht = kzalloc(sizeof(*tmp_sdma_rht), GFP_KERNEL);
1518 	if (!tmp_sdma_rht) {
1519 		ret = -ENOMEM;
1520 		goto bail;
1521 	}
1522 
1523 	ret = rhashtable_init(tmp_sdma_rht, &sdma_rht_params);
1524 	if (ret < 0)
1525 		goto bail;
1526 	dd->sdma_rht = tmp_sdma_rht;
1527 
1528 	dd_dev_info(dd, "SDMA num_sdma: %u\n", dd->num_sdma);
1529 	return 0;
1530 
1531 bail:
1532 	sdma_clean(dd, num_engines);
1533 	return ret;
1534 }
1535 
1536 /**
1537  * sdma_all_running() - called when the link goes up
1538  * @dd: hfi1_devdata
1539  *
1540  * This routine moves all engines to the running state.
1541  */
1542 void sdma_all_running(struct hfi1_devdata *dd)
1543 {
1544 	struct sdma_engine *sde;
1545 	unsigned int i;
1546 
1547 	/* move all engines to running */
1548 	for (i = 0; i < dd->num_sdma; ++i) {
1549 		sde = &dd->per_sdma[i];
1550 		sdma_process_event(sde, sdma_event_e30_go_running);
1551 	}
1552 }
1553 
1554 /**
1555  * sdma_all_idle() - called when the link goes down
1556  * @dd: hfi1_devdata
1557  *
1558  * This routine moves all engines to the idle state.
1559  */
1560 void sdma_all_idle(struct hfi1_devdata *dd)
1561 {
1562 	struct sdma_engine *sde;
1563 	unsigned int i;
1564 
1565 	/* idle all engines */
1566 	for (i = 0; i < dd->num_sdma; ++i) {
1567 		sde = &dd->per_sdma[i];
1568 		sdma_process_event(sde, sdma_event_e70_go_idle);
1569 	}
1570 }
1571 
1572 /**
1573  * sdma_start() - called to kick off state processing for all engines
1574  * @dd: hfi1_devdata
1575  *
1576  * This routine is for kicking off the state processing for all required
1577  * sdma engines.  Interrupts need to be working at this point.
1578  *
1579  */
1580 void sdma_start(struct hfi1_devdata *dd)
1581 {
1582 	unsigned i;
1583 	struct sdma_engine *sde;
1584 
1585 	/* kick off the engines state processing */
1586 	for (i = 0; i < dd->num_sdma; ++i) {
1587 		sde = &dd->per_sdma[i];
1588 		sdma_process_event(sde, sdma_event_e10_go_hw_start);
1589 	}
1590 }
1591 
1592 /**
1593  * sdma_exit() - used when module is removed
1594  * @dd: hfi1_devdata
1595  */
1596 void sdma_exit(struct hfi1_devdata *dd)
1597 {
1598 	unsigned this_idx;
1599 	struct sdma_engine *sde;
1600 
1601 	for (this_idx = 0; dd->per_sdma && this_idx < dd->num_sdma;
1602 			++this_idx) {
1603 		sde = &dd->per_sdma[this_idx];
1604 		if (!list_empty(&sde->dmawait))
1605 			dd_dev_err(dd, "sde %u: dmawait list not empty!\n",
1606 				   sde->this_idx);
1607 		sdma_process_event(sde, sdma_event_e00_go_hw_down);
1608 
1609 		del_timer_sync(&sde->err_progress_check_timer);
1610 
1611 		/*
1612 		 * This waits for the state machine to exit so it is not
1613 		 * necessary to kill the sdma_sw_clean_up_task to make sure
1614 		 * it is not running.
1615 		 */
1616 		sdma_finalput(&sde->state);
1617 	}
1618 }
1619 
1620 /*
1621  * unmap the indicated descriptor
1622  */
1623 static inline void sdma_unmap_desc(
1624 	struct hfi1_devdata *dd,
1625 	struct sdma_desc *descp)
1626 {
1627 	switch (sdma_mapping_type(descp)) {
1628 	case SDMA_MAP_SINGLE:
1629 		dma_unmap_single(
1630 			&dd->pcidev->dev,
1631 			sdma_mapping_addr(descp),
1632 			sdma_mapping_len(descp),
1633 			DMA_TO_DEVICE);
1634 		break;
1635 	case SDMA_MAP_PAGE:
1636 		dma_unmap_page(
1637 			&dd->pcidev->dev,
1638 			sdma_mapping_addr(descp),
1639 			sdma_mapping_len(descp),
1640 			DMA_TO_DEVICE);
1641 		break;
1642 	}
1643 }
1644 
1645 /*
1646  * return the mode as indicated by the first
1647  * descriptor in the tx.
1648  */
1649 static inline u8 ahg_mode(struct sdma_txreq *tx)
1650 {
1651 	return (tx->descp[0].qw[1] & SDMA_DESC1_HEADER_MODE_SMASK)
1652 		>> SDMA_DESC1_HEADER_MODE_SHIFT;
1653 }
1654 
1655 /**
1656  * __sdma_txclean() - clean tx of mappings, descp *kmalloc's
1657  * @dd: hfi1_devdata for unmapping
1658  * @tx: tx request to clean
1659  *
1660  * This is used in the progress routine to clean the tx or
1661  * by the ULP to toss an in-process tx build.
1662  *
1663  * The code can be called multiple times without issue.
1664  *
1665  */
1666 void __sdma_txclean(
1667 	struct hfi1_devdata *dd,
1668 	struct sdma_txreq *tx)
1669 {
1670 	u16 i;
1671 
1672 	if (tx->num_desc) {
1673 		u8 skip = 0, mode = ahg_mode(tx);
1674 
1675 		/* unmap first */
1676 		sdma_unmap_desc(dd, &tx->descp[0]);
1677 		/* determine number of AHG descriptors to skip */
1678 		if (mode > SDMA_AHG_APPLY_UPDATE1)
1679 			skip = mode >> 1;
1680 		for (i = 1 + skip; i < tx->num_desc; i++)
1681 			sdma_unmap_desc(dd, &tx->descp[i]);
1682 		tx->num_desc = 0;
1683 	}
1684 	kfree(tx->coalesce_buf);
1685 	tx->coalesce_buf = NULL;
1686 	/* kmalloc'ed descp */
1687 	if (unlikely(tx->desc_limit > ARRAY_SIZE(tx->descs))) {
1688 		tx->desc_limit = ARRAY_SIZE(tx->descs);
1689 		kfree(tx->descp);
1690 	}
1691 }
1692 
1693 static inline u16 sdma_gethead(struct sdma_engine *sde)
1694 {
1695 	struct hfi1_devdata *dd = sde->dd;
1696 	int use_dmahead;
1697 	u16 hwhead;
1698 
1699 #ifdef CONFIG_SDMA_VERBOSITY
1700 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1701 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1702 #endif
1703 
1704 retry:
1705 	use_dmahead = HFI1_CAP_IS_KSET(USE_SDMA_HEAD) && __sdma_running(sde) &&
1706 					(dd->flags & HFI1_HAS_SDMA_TIMEOUT);
1707 	hwhead = use_dmahead ?
1708 		(u16)le64_to_cpu(*sde->head_dma) :
1709 		(u16)read_sde_csr(sde, SD(HEAD));
1710 
1711 	if (unlikely(HFI1_CAP_IS_KSET(SDMA_HEAD_CHECK))) {
1712 		u16 cnt;
1713 		u16 swtail;
1714 		u16 swhead;
1715 		int sane;
1716 
1717 		swhead = sde->descq_head & sde->sdma_mask;
1718 		/* this code is really bad for cache line trading */
1719 		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1720 		cnt = sde->descq_cnt;
1721 
1722 		if (swhead < swtail)
1723 			/* not wrapped */
1724 			sane = (hwhead >= swhead) & (hwhead <= swtail);
1725 		else if (swhead > swtail)
1726 			/* wrapped around */
1727 			sane = ((hwhead >= swhead) && (hwhead < cnt)) ||
1728 				(hwhead <= swtail);
1729 		else
1730 			/* empty */
1731 			sane = (hwhead == swhead);
1732 
1733 		if (unlikely(!sane)) {
1734 			dd_dev_err(dd, "SDMA(%u) bad head (%s) hwhd=%hu swhd=%hu swtl=%hu cnt=%hu\n",
1735 				   sde->this_idx,
1736 				   use_dmahead ? "dma" : "kreg",
1737 				   hwhead, swhead, swtail, cnt);
1738 			if (use_dmahead) {
1739 				/* try one more time, using csr */
1740 				use_dmahead = 0;
1741 				goto retry;
1742 			}
1743 			/* proceed as if no progress */
1744 			hwhead = swhead;
1745 		}
1746 	}
1747 	return hwhead;
1748 }
1749 
1750 /*
1751  * This is called when there are send DMA descriptors that might be
1752  * available.
1753  *
1754  * This is called with head_lock held.
1755  */
1756 static void sdma_desc_avail(struct sdma_engine *sde, uint avail)
1757 {
1758 	struct iowait *wait, *nw;
1759 	struct iowait *waits[SDMA_WAIT_BATCH_SIZE];
1760 	uint i, n = 0, seq, max_idx = 0;
1761 	struct sdma_txreq *stx;
1762 	struct hfi1_ibdev *dev = &sde->dd->verbs_dev;
1763 	u8 max_starved_cnt = 0;
1764 
1765 #ifdef CONFIG_SDMA_VERBOSITY
1766 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n", sde->this_idx,
1767 		   slashstrip(__FILE__), __LINE__, __func__);
1768 	dd_dev_err(sde->dd, "avail: %u\n", avail);
1769 #endif
1770 
1771 	do {
1772 		seq = read_seqbegin(&dev->iowait_lock);
1773 		if (!list_empty(&sde->dmawait)) {
1774 			/* at least one item */
1775 			write_seqlock(&dev->iowait_lock);
1776 			/* Harvest waiters wanting DMA descriptors */
1777 			list_for_each_entry_safe(
1778 					wait,
1779 					nw,
1780 					&sde->dmawait,
1781 					list) {
1782 				u16 num_desc = 0;
1783 
1784 				if (!wait->wakeup)
1785 					continue;
1786 				if (n == ARRAY_SIZE(waits))
1787 					break;
1788 				if (!list_empty(&wait->tx_head)) {
1789 					stx = list_first_entry(
1790 						&wait->tx_head,
1791 						struct sdma_txreq,
1792 						list);
1793 					num_desc = stx->num_desc;
1794 				}
1795 				if (num_desc > avail)
1796 					break;
1797 				avail -= num_desc;
1798 				/* Find the most starved wait memeber */
1799 				iowait_starve_find_max(wait, &max_starved_cnt,
1800 						       n, &max_idx);
1801 				list_del_init(&wait->list);
1802 				waits[n++] = wait;
1803 			}
1804 			write_sequnlock(&dev->iowait_lock);
1805 			break;
1806 		}
1807 	} while (read_seqretry(&dev->iowait_lock, seq));
1808 
1809 	/* Schedule the most starved one first */
1810 	if (n)
1811 		waits[max_idx]->wakeup(waits[max_idx], SDMA_AVAIL_REASON);
1812 
1813 	for (i = 0; i < n; i++)
1814 		if (i != max_idx)
1815 			waits[i]->wakeup(waits[i], SDMA_AVAIL_REASON);
1816 }
1817 
1818 /* head_lock must be held */
1819 static void sdma_make_progress(struct sdma_engine *sde, u64 status)
1820 {
1821 	struct sdma_txreq *txp = NULL;
1822 	int progress = 0;
1823 	u16 hwhead, swhead;
1824 	int idle_check_done = 0;
1825 
1826 	hwhead = sdma_gethead(sde);
1827 
1828 	/* The reason for some of the complexity of this code is that
1829 	 * not all descriptors have corresponding txps.  So, we have to
1830 	 * be able to skip over descs until we wander into the range of
1831 	 * the next txp on the list.
1832 	 */
1833 
1834 retry:
1835 	txp = get_txhead(sde);
1836 	swhead = sde->descq_head & sde->sdma_mask;
1837 	trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1838 	while (swhead != hwhead) {
1839 		/* advance head, wrap if needed */
1840 		swhead = ++sde->descq_head & sde->sdma_mask;
1841 
1842 		/* if now past this txp's descs, do the callback */
1843 		if (txp && txp->next_descq_idx == swhead) {
1844 			/* remove from list */
1845 			sde->tx_ring[sde->tx_head++ & sde->sdma_mask] = NULL;
1846 			complete_tx(sde, txp, SDMA_TXREQ_S_OK);
1847 			/* see if there is another txp */
1848 			txp = get_txhead(sde);
1849 		}
1850 		trace_hfi1_sdma_progress(sde, hwhead, swhead, txp);
1851 		progress++;
1852 	}
1853 
1854 	/*
1855 	 * The SDMA idle interrupt is not guaranteed to be ordered with respect
1856 	 * to updates to the the dma_head location in host memory. The head
1857 	 * value read might not be fully up to date. If there are pending
1858 	 * descriptors and the SDMA idle interrupt fired then read from the
1859 	 * CSR SDMA head instead to get the latest value from the hardware.
1860 	 * The hardware SDMA head should be read at most once in this invocation
1861 	 * of sdma_make_progress(..) which is ensured by idle_check_done flag
1862 	 */
1863 	if ((status & sde->idle_mask) && !idle_check_done) {
1864 		u16 swtail;
1865 
1866 		swtail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
1867 		if (swtail != hwhead) {
1868 			hwhead = (u16)read_sde_csr(sde, SD(HEAD));
1869 			idle_check_done = 1;
1870 			goto retry;
1871 		}
1872 	}
1873 
1874 	sde->last_status = status;
1875 	if (progress)
1876 		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
1877 }
1878 
1879 /*
1880  * sdma_engine_interrupt() - interrupt handler for engine
1881  * @sde: sdma engine
1882  * @status: sdma interrupt reason
1883  *
1884  * Status is a mask of the 3 possible interrupts for this engine.  It will
1885  * contain bits _only_ for this SDMA engine.  It will contain at least one
1886  * bit, it may contain more.
1887  */
1888 void sdma_engine_interrupt(struct sdma_engine *sde, u64 status)
1889 {
1890 	trace_hfi1_sdma_engine_interrupt(sde, status);
1891 	write_seqlock(&sde->head_lock);
1892 	sdma_set_desc_cnt(sde, sdma_desct_intr);
1893 	if (status & sde->idle_mask)
1894 		sde->idle_int_cnt++;
1895 	else if (status & sde->progress_mask)
1896 		sde->progress_int_cnt++;
1897 	else if (status & sde->int_mask)
1898 		sde->sdma_int_cnt++;
1899 	sdma_make_progress(sde, status);
1900 	write_sequnlock(&sde->head_lock);
1901 }
1902 
1903 /**
1904  * sdma_engine_error() - error handler for engine
1905  * @sde: sdma engine
1906  * @status: sdma interrupt reason
1907  */
1908 void sdma_engine_error(struct sdma_engine *sde, u64 status)
1909 {
1910 	unsigned long flags;
1911 
1912 #ifdef CONFIG_SDMA_VERBOSITY
1913 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) error status 0x%llx state %s\n",
1914 		   sde->this_idx,
1915 		   (unsigned long long)status,
1916 		   sdma_state_names[sde->state.current_state]);
1917 #endif
1918 	spin_lock_irqsave(&sde->tail_lock, flags);
1919 	write_seqlock(&sde->head_lock);
1920 	if (status & ALL_SDMA_ENG_HALT_ERRS)
1921 		__sdma_process_event(sde, sdma_event_e60_hw_halted);
1922 	if (status & ~SD(ENG_ERR_STATUS_SDMA_HALT_ERR_SMASK)) {
1923 		dd_dev_err(sde->dd,
1924 			   "SDMA (%u) engine error: 0x%llx state %s\n",
1925 			   sde->this_idx,
1926 			   (unsigned long long)status,
1927 			   sdma_state_names[sde->state.current_state]);
1928 		dump_sdma_state(sde);
1929 	}
1930 	write_sequnlock(&sde->head_lock);
1931 	spin_unlock_irqrestore(&sde->tail_lock, flags);
1932 }
1933 
1934 static void sdma_sendctrl(struct sdma_engine *sde, unsigned op)
1935 {
1936 	u64 set_senddmactrl = 0;
1937 	u64 clr_senddmactrl = 0;
1938 	unsigned long flags;
1939 
1940 #ifdef CONFIG_SDMA_VERBOSITY
1941 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) senddmactrl E=%d I=%d H=%d C=%d\n",
1942 		   sde->this_idx,
1943 		   (op & SDMA_SENDCTRL_OP_ENABLE) ? 1 : 0,
1944 		   (op & SDMA_SENDCTRL_OP_INTENABLE) ? 1 : 0,
1945 		   (op & SDMA_SENDCTRL_OP_HALT) ? 1 : 0,
1946 		   (op & SDMA_SENDCTRL_OP_CLEANUP) ? 1 : 0);
1947 #endif
1948 
1949 	if (op & SDMA_SENDCTRL_OP_ENABLE)
1950 		set_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1951 	else
1952 		clr_senddmactrl |= SD(CTRL_SDMA_ENABLE_SMASK);
1953 
1954 	if (op & SDMA_SENDCTRL_OP_INTENABLE)
1955 		set_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1956 	else
1957 		clr_senddmactrl |= SD(CTRL_SDMA_INT_ENABLE_SMASK);
1958 
1959 	if (op & SDMA_SENDCTRL_OP_HALT)
1960 		set_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1961 	else
1962 		clr_senddmactrl |= SD(CTRL_SDMA_HALT_SMASK);
1963 
1964 	spin_lock_irqsave(&sde->senddmactrl_lock, flags);
1965 
1966 	sde->p_senddmactrl |= set_senddmactrl;
1967 	sde->p_senddmactrl &= ~clr_senddmactrl;
1968 
1969 	if (op & SDMA_SENDCTRL_OP_CLEANUP)
1970 		write_sde_csr(sde, SD(CTRL),
1971 			      sde->p_senddmactrl |
1972 			      SD(CTRL_SDMA_CLEANUP_SMASK));
1973 	else
1974 		write_sde_csr(sde, SD(CTRL), sde->p_senddmactrl);
1975 
1976 	spin_unlock_irqrestore(&sde->senddmactrl_lock, flags);
1977 
1978 #ifdef CONFIG_SDMA_VERBOSITY
1979 	sdma_dumpstate(sde);
1980 #endif
1981 }
1982 
1983 static void sdma_setlengen(struct sdma_engine *sde)
1984 {
1985 #ifdef CONFIG_SDMA_VERBOSITY
1986 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
1987 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
1988 #endif
1989 
1990 	/*
1991 	 * Set SendDmaLenGen and clear-then-set the MSB of the generation
1992 	 * count to enable generation checking and load the internal
1993 	 * generation counter.
1994 	 */
1995 	write_sde_csr(sde, SD(LEN_GEN),
1996 		      (sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT));
1997 	write_sde_csr(sde, SD(LEN_GEN),
1998 		      ((sde->descq_cnt / 64) << SD(LEN_GEN_LENGTH_SHIFT)) |
1999 		      (4ULL << SD(LEN_GEN_GENERATION_SHIFT)));
2000 }
2001 
2002 static inline void sdma_update_tail(struct sdma_engine *sde, u16 tail)
2003 {
2004 	/* Commit writes to memory and advance the tail on the chip */
2005 	smp_wmb(); /* see get_txhead() */
2006 	writeq(tail, sde->tail_csr);
2007 }
2008 
2009 /*
2010  * This is called when changing to state s10_hw_start_up_halt_wait as
2011  * a result of send buffer errors or send DMA descriptor errors.
2012  */
2013 static void sdma_hw_start_up(struct sdma_engine *sde)
2014 {
2015 	u64 reg;
2016 
2017 #ifdef CONFIG_SDMA_VERBOSITY
2018 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2019 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2020 #endif
2021 
2022 	sdma_setlengen(sde);
2023 	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2024 	*sde->head_dma = 0;
2025 
2026 	reg = SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_MASK) <<
2027 	      SD(ENG_ERR_CLEAR_SDMA_HEADER_REQUEST_FIFO_UNC_ERR_SHIFT);
2028 	write_sde_csr(sde, SD(ENG_ERR_CLEAR), reg);
2029 }
2030 
2031 /*
2032  * set_sdma_integrity
2033  *
2034  * Set the SEND_DMA_CHECK_ENABLE register for send DMA engine 'sde'.
2035  */
2036 static void set_sdma_integrity(struct sdma_engine *sde)
2037 {
2038 	struct hfi1_devdata *dd = sde->dd;
2039 
2040 	write_sde_csr(sde, SD(CHECK_ENABLE),
2041 		      hfi1_pkt_base_sdma_integrity(dd));
2042 }
2043 
2044 static void init_sdma_regs(
2045 	struct sdma_engine *sde,
2046 	u32 credits,
2047 	uint idle_cnt)
2048 {
2049 	u8 opval, opmask;
2050 #ifdef CONFIG_SDMA_VERBOSITY
2051 	struct hfi1_devdata *dd = sde->dd;
2052 
2053 	dd_dev_err(dd, "CONFIG SDMA(%u) %s:%d %s()\n",
2054 		   sde->this_idx, slashstrip(__FILE__), __LINE__, __func__);
2055 #endif
2056 
2057 	write_sde_csr(sde, SD(BASE_ADDR), sde->descq_phys);
2058 	sdma_setlengen(sde);
2059 	sdma_update_tail(sde, 0); /* Set SendDmaTail */
2060 	write_sde_csr(sde, SD(RELOAD_CNT), idle_cnt);
2061 	write_sde_csr(sde, SD(DESC_CNT), 0);
2062 	write_sde_csr(sde, SD(HEAD_ADDR), sde->head_phys);
2063 	write_sde_csr(sde, SD(MEMORY),
2064 		      ((u64)credits << SD(MEMORY_SDMA_MEMORY_CNT_SHIFT)) |
2065 		      ((u64)(credits * sde->this_idx) <<
2066 		       SD(MEMORY_SDMA_MEMORY_INDEX_SHIFT)));
2067 	write_sde_csr(sde, SD(ENG_ERR_MASK), ~0ull);
2068 	set_sdma_integrity(sde);
2069 	opmask = OPCODE_CHECK_MASK_DISABLED;
2070 	opval = OPCODE_CHECK_VAL_DISABLED;
2071 	write_sde_csr(sde, SD(CHECK_OPCODE),
2072 		      (opmask << SEND_CTXT_CHECK_OPCODE_MASK_SHIFT) |
2073 		      (opval << SEND_CTXT_CHECK_OPCODE_VALUE_SHIFT));
2074 }
2075 
2076 #ifdef CONFIG_SDMA_VERBOSITY
2077 
2078 #define sdma_dumpstate_helper0(reg) do { \
2079 		csr = read_csr(sde->dd, reg); \
2080 		dd_dev_err(sde->dd, "%36s     0x%016llx\n", #reg, csr); \
2081 	} while (0)
2082 
2083 #define sdma_dumpstate_helper(reg) do { \
2084 		csr = read_sde_csr(sde, reg); \
2085 		dd_dev_err(sde->dd, "%36s[%02u] 0x%016llx\n", \
2086 			#reg, sde->this_idx, csr); \
2087 	} while (0)
2088 
2089 #define sdma_dumpstate_helper2(reg) do { \
2090 		csr = read_csr(sde->dd, reg + (8 * i)); \
2091 		dd_dev_err(sde->dd, "%33s_%02u     0x%016llx\n", \
2092 				#reg, i, csr); \
2093 	} while (0)
2094 
2095 void sdma_dumpstate(struct sdma_engine *sde)
2096 {
2097 	u64 csr;
2098 	unsigned i;
2099 
2100 	sdma_dumpstate_helper(SD(CTRL));
2101 	sdma_dumpstate_helper(SD(STATUS));
2102 	sdma_dumpstate_helper0(SD(ERR_STATUS));
2103 	sdma_dumpstate_helper0(SD(ERR_MASK));
2104 	sdma_dumpstate_helper(SD(ENG_ERR_STATUS));
2105 	sdma_dumpstate_helper(SD(ENG_ERR_MASK));
2106 
2107 	for (i = 0; i < CCE_NUM_INT_CSRS; ++i) {
2108 		sdma_dumpstate_helper2(CCE_INT_STATUS);
2109 		sdma_dumpstate_helper2(CCE_INT_MASK);
2110 		sdma_dumpstate_helper2(CCE_INT_BLOCKED);
2111 	}
2112 
2113 	sdma_dumpstate_helper(SD(TAIL));
2114 	sdma_dumpstate_helper(SD(HEAD));
2115 	sdma_dumpstate_helper(SD(PRIORITY_THLD));
2116 	sdma_dumpstate_helper(SD(IDLE_CNT));
2117 	sdma_dumpstate_helper(SD(RELOAD_CNT));
2118 	sdma_dumpstate_helper(SD(DESC_CNT));
2119 	sdma_dumpstate_helper(SD(DESC_FETCHED_CNT));
2120 	sdma_dumpstate_helper(SD(MEMORY));
2121 	sdma_dumpstate_helper0(SD(ENGINES));
2122 	sdma_dumpstate_helper0(SD(MEM_SIZE));
2123 	/* sdma_dumpstate_helper(SEND_EGRESS_SEND_DMA_STATUS);  */
2124 	sdma_dumpstate_helper(SD(BASE_ADDR));
2125 	sdma_dumpstate_helper(SD(LEN_GEN));
2126 	sdma_dumpstate_helper(SD(HEAD_ADDR));
2127 	sdma_dumpstate_helper(SD(CHECK_ENABLE));
2128 	sdma_dumpstate_helper(SD(CHECK_VL));
2129 	sdma_dumpstate_helper(SD(CHECK_JOB_KEY));
2130 	sdma_dumpstate_helper(SD(CHECK_PARTITION_KEY));
2131 	sdma_dumpstate_helper(SD(CHECK_SLID));
2132 	sdma_dumpstate_helper(SD(CHECK_OPCODE));
2133 }
2134 #endif
2135 
2136 static void dump_sdma_state(struct sdma_engine *sde)
2137 {
2138 	struct hw_sdma_desc *descqp;
2139 	u64 desc[2];
2140 	u64 addr;
2141 	u8 gen;
2142 	u16 len;
2143 	u16 head, tail, cnt;
2144 
2145 	head = sde->descq_head & sde->sdma_mask;
2146 	tail = sde->descq_tail & sde->sdma_mask;
2147 	cnt = sdma_descq_freecnt(sde);
2148 
2149 	dd_dev_err(sde->dd,
2150 		   "SDMA (%u) descq_head: %u descq_tail: %u freecnt: %u FLE %d\n",
2151 		   sde->this_idx, head, tail, cnt,
2152 		   !list_empty(&sde->flushlist));
2153 
2154 	/* print info for each entry in the descriptor queue */
2155 	while (head != tail) {
2156 		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2157 
2158 		descqp = &sde->descq[head];
2159 		desc[0] = le64_to_cpu(descqp->qw[0]);
2160 		desc[1] = le64_to_cpu(descqp->qw[1]);
2161 		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2162 		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2163 				'H' : '-';
2164 		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2165 		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2166 		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2167 			& SDMA_DESC0_PHY_ADDR_MASK;
2168 		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2169 			& SDMA_DESC1_GENERATION_MASK;
2170 		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2171 			& SDMA_DESC0_BYTE_COUNT_MASK;
2172 		dd_dev_err(sde->dd,
2173 			   "SDMA sdmadesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2174 			   head, flags, addr, gen, len);
2175 		dd_dev_err(sde->dd,
2176 			   "\tdesc0:0x%016llx desc1 0x%016llx\n",
2177 			   desc[0], desc[1]);
2178 		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2179 			dd_dev_err(sde->dd,
2180 				   "\taidx: %u amode: %u alen: %u\n",
2181 				   (u8)((desc[1] &
2182 					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2183 					SDMA_DESC1_HEADER_INDEX_SHIFT),
2184 				   (u8)((desc[1] &
2185 					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2186 					SDMA_DESC1_HEADER_MODE_SHIFT),
2187 				   (u8)((desc[1] &
2188 					 SDMA_DESC1_HEADER_DWS_SMASK) >>
2189 					SDMA_DESC1_HEADER_DWS_SHIFT));
2190 		head++;
2191 		head &= sde->sdma_mask;
2192 	}
2193 }
2194 
2195 #define SDE_FMT \
2196 	"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"
2197 /**
2198  * sdma_seqfile_dump_sde() - debugfs dump of sde
2199  * @s: seq file
2200  * @sde: send dma engine to dump
2201  *
2202  * This routine dumps the sde to the indicated seq file.
2203  */
2204 void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *sde)
2205 {
2206 	u16 head, tail;
2207 	struct hw_sdma_desc *descqp;
2208 	u64 desc[2];
2209 	u64 addr;
2210 	u8 gen;
2211 	u16 len;
2212 
2213 	head = sde->descq_head & sde->sdma_mask;
2214 	tail = READ_ONCE(sde->descq_tail) & sde->sdma_mask;
2215 	seq_printf(s, SDE_FMT, sde->this_idx,
2216 		   sde->cpu,
2217 		   sdma_state_name(sde->state.current_state),
2218 		   (unsigned long long)read_sde_csr(sde, SD(CTRL)),
2219 		   (unsigned long long)read_sde_csr(sde, SD(STATUS)),
2220 		   (unsigned long long)read_sde_csr(sde, SD(ENG_ERR_STATUS)),
2221 		   (unsigned long long)read_sde_csr(sde, SD(TAIL)), tail,
2222 		   (unsigned long long)read_sde_csr(sde, SD(HEAD)), head,
2223 		   (unsigned long long)le64_to_cpu(*sde->head_dma),
2224 		   (unsigned long long)read_sde_csr(sde, SD(MEMORY)),
2225 		   (unsigned long long)read_sde_csr(sde, SD(LEN_GEN)),
2226 		   (unsigned long long)read_sde_csr(sde, SD(RELOAD_CNT)),
2227 		   (unsigned long long)sde->last_status,
2228 		   (unsigned long long)sde->ahg_bits,
2229 		   sde->tx_tail,
2230 		   sde->tx_head,
2231 		   sde->descq_tail,
2232 		   sde->descq_head,
2233 		   !list_empty(&sde->flushlist),
2234 		   sde->descq_full_count,
2235 		   (unsigned long long)read_sde_csr(sde, SEND_DMA_CHECK_SLID));
2236 
2237 	/* print info for each entry in the descriptor queue */
2238 	while (head != tail) {
2239 		char flags[6] = { 'x', 'x', 'x', 'x', 0 };
2240 
2241 		descqp = &sde->descq[head];
2242 		desc[0] = le64_to_cpu(descqp->qw[0]);
2243 		desc[1] = le64_to_cpu(descqp->qw[1]);
2244 		flags[0] = (desc[1] & SDMA_DESC1_INT_REQ_FLAG) ? 'I' : '-';
2245 		flags[1] = (desc[1] & SDMA_DESC1_HEAD_TO_HOST_FLAG) ?
2246 				'H' : '-';
2247 		flags[2] = (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG) ? 'F' : '-';
2248 		flags[3] = (desc[0] & SDMA_DESC0_LAST_DESC_FLAG) ? 'L' : '-';
2249 		addr = (desc[0] >> SDMA_DESC0_PHY_ADDR_SHIFT)
2250 			& SDMA_DESC0_PHY_ADDR_MASK;
2251 		gen = (desc[1] >> SDMA_DESC1_GENERATION_SHIFT)
2252 			& SDMA_DESC1_GENERATION_MASK;
2253 		len = (desc[0] >> SDMA_DESC0_BYTE_COUNT_SHIFT)
2254 			& SDMA_DESC0_BYTE_COUNT_MASK;
2255 		seq_printf(s,
2256 			   "\tdesc[%u]: flags:%s addr:0x%016llx gen:%u len:%u bytes\n",
2257 			   head, flags, addr, gen, len);
2258 		if (desc[0] & SDMA_DESC0_FIRST_DESC_FLAG)
2259 			seq_printf(s, "\t\tahgidx: %u ahgmode: %u\n",
2260 				   (u8)((desc[1] &
2261 					 SDMA_DESC1_HEADER_INDEX_SMASK) >>
2262 					SDMA_DESC1_HEADER_INDEX_SHIFT),
2263 				   (u8)((desc[1] &
2264 					 SDMA_DESC1_HEADER_MODE_SMASK) >>
2265 					SDMA_DESC1_HEADER_MODE_SHIFT));
2266 		head = (head + 1) & sde->sdma_mask;
2267 	}
2268 }
2269 
2270 /*
2271  * add the generation number into
2272  * the qw1 and return
2273  */
2274 static inline u64 add_gen(struct sdma_engine *sde, u64 qw1)
2275 {
2276 	u8 generation = (sde->descq_tail >> sde->sdma_shift) & 3;
2277 
2278 	qw1 &= ~SDMA_DESC1_GENERATION_SMASK;
2279 	qw1 |= ((u64)generation & SDMA_DESC1_GENERATION_MASK)
2280 			<< SDMA_DESC1_GENERATION_SHIFT;
2281 	return qw1;
2282 }
2283 
2284 /*
2285  * This routine submits the indicated tx
2286  *
2287  * Space has already been guaranteed and
2288  * tail side of ring is locked.
2289  *
2290  * The hardware tail update is done
2291  * in the caller and that is facilitated
2292  * by returning the new tail.
2293  *
2294  * There is special case logic for ahg
2295  * to not add the generation number for
2296  * up to 2 descriptors that follow the
2297  * first descriptor.
2298  *
2299  */
2300 static inline u16 submit_tx(struct sdma_engine *sde, struct sdma_txreq *tx)
2301 {
2302 	int i;
2303 	u16 tail;
2304 	struct sdma_desc *descp = tx->descp;
2305 	u8 skip = 0, mode = ahg_mode(tx);
2306 
2307 	tail = sde->descq_tail & sde->sdma_mask;
2308 	sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2309 	sde->descq[tail].qw[1] = cpu_to_le64(add_gen(sde, descp->qw[1]));
2310 	trace_hfi1_sdma_descriptor(sde, descp->qw[0], descp->qw[1],
2311 				   tail, &sde->descq[tail]);
2312 	tail = ++sde->descq_tail & sde->sdma_mask;
2313 	descp++;
2314 	if (mode > SDMA_AHG_APPLY_UPDATE1)
2315 		skip = mode >> 1;
2316 	for (i = 1; i < tx->num_desc; i++, descp++) {
2317 		u64 qw1;
2318 
2319 		sde->descq[tail].qw[0] = cpu_to_le64(descp->qw[0]);
2320 		if (skip) {
2321 			/* edits don't have generation */
2322 			qw1 = descp->qw[1];
2323 			skip--;
2324 		} else {
2325 			/* replace generation with real one for non-edits */
2326 			qw1 = add_gen(sde, descp->qw[1]);
2327 		}
2328 		sde->descq[tail].qw[1] = cpu_to_le64(qw1);
2329 		trace_hfi1_sdma_descriptor(sde, descp->qw[0], qw1,
2330 					   tail, &sde->descq[tail]);
2331 		tail = ++sde->descq_tail & sde->sdma_mask;
2332 	}
2333 	tx->next_descq_idx = tail;
2334 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2335 	tx->sn = sde->tail_sn++;
2336 	trace_hfi1_sdma_in_sn(sde, tx->sn);
2337 	WARN_ON_ONCE(sde->tx_ring[sde->tx_tail & sde->sdma_mask]);
2338 #endif
2339 	sde->tx_ring[sde->tx_tail++ & sde->sdma_mask] = tx;
2340 	sde->desc_avail -= tx->num_desc;
2341 	return tail;
2342 }
2343 
2344 /*
2345  * Check for progress
2346  */
2347 static int sdma_check_progress(
2348 	struct sdma_engine *sde,
2349 	struct iowait *wait,
2350 	struct sdma_txreq *tx,
2351 	bool pkts_sent)
2352 {
2353 	int ret;
2354 
2355 	sde->desc_avail = sdma_descq_freecnt(sde);
2356 	if (tx->num_desc <= sde->desc_avail)
2357 		return -EAGAIN;
2358 	/* pulse the head_lock */
2359 	if (wait && wait->sleep) {
2360 		unsigned seq;
2361 
2362 		seq = raw_seqcount_begin(
2363 			(const seqcount_t *)&sde->head_lock.seqcount);
2364 		ret = wait->sleep(sde, wait, tx, seq, pkts_sent);
2365 		if (ret == -EAGAIN)
2366 			sde->desc_avail = sdma_descq_freecnt(sde);
2367 	} else {
2368 		ret = -EBUSY;
2369 	}
2370 	return ret;
2371 }
2372 
2373 /**
2374  * sdma_send_txreq() - submit a tx req to ring
2375  * @sde: sdma engine to use
2376  * @wait: wait structure to use when full (may be NULL)
2377  * @tx: sdma_txreq to submit
2378  * @pkts_sent: has any packet been sent yet?
2379  *
2380  * The call submits the tx into the ring.  If a iowait structure is non-NULL
2381  * the packet will be queued to the list in wait.
2382  *
2383  * Return:
2384  * 0 - Success, -EINVAL - sdma_txreq incomplete, -EBUSY - no space in
2385  * ring (wait == NULL)
2386  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2387  */
2388 int sdma_send_txreq(struct sdma_engine *sde,
2389 		    struct iowait *wait,
2390 		    struct sdma_txreq *tx,
2391 		    bool pkts_sent)
2392 {
2393 	int ret = 0;
2394 	u16 tail;
2395 	unsigned long flags;
2396 
2397 	/* user should have supplied entire packet */
2398 	if (unlikely(tx->tlen))
2399 		return -EINVAL;
2400 	tx->wait = wait;
2401 	spin_lock_irqsave(&sde->tail_lock, flags);
2402 retry:
2403 	if (unlikely(!__sdma_running(sde)))
2404 		goto unlock_noconn;
2405 	if (unlikely(tx->num_desc > sde->desc_avail))
2406 		goto nodesc;
2407 	tail = submit_tx(sde, tx);
2408 	if (wait)
2409 		iowait_sdma_inc(wait);
2410 	sdma_update_tail(sde, tail);
2411 unlock:
2412 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2413 	return ret;
2414 unlock_noconn:
2415 	if (wait)
2416 		iowait_sdma_inc(wait);
2417 	tx->next_descq_idx = 0;
2418 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2419 	tx->sn = sde->tail_sn++;
2420 	trace_hfi1_sdma_in_sn(sde, tx->sn);
2421 #endif
2422 	spin_lock(&sde->flushlist_lock);
2423 	list_add_tail(&tx->list, &sde->flushlist);
2424 	spin_unlock(&sde->flushlist_lock);
2425 	if (wait) {
2426 		wait->tx_count++;
2427 		wait->count += tx->num_desc;
2428 	}
2429 	schedule_work(&sde->flush_worker);
2430 	ret = -ECOMM;
2431 	goto unlock;
2432 nodesc:
2433 	ret = sdma_check_progress(sde, wait, tx, pkts_sent);
2434 	if (ret == -EAGAIN) {
2435 		ret = 0;
2436 		goto retry;
2437 	}
2438 	sde->descq_full_count++;
2439 	goto unlock;
2440 }
2441 
2442 /**
2443  * sdma_send_txlist() - submit a list of tx req to ring
2444  * @sde: sdma engine to use
2445  * @wait: wait structure to use when full (may be NULL)
2446  * @tx_list: list of sdma_txreqs to submit
2447  * @count: pointer to a u32 which, after return will contain the total number of
2448  *         sdma_txreqs removed from the tx_list. This will include sdma_txreqs
2449  *         whose SDMA descriptors are submitted to the ring and the sdma_txreqs
2450  *         which are added to SDMA engine flush list if the SDMA engine state is
2451  *         not running.
2452  *
2453  * The call submits the list into the ring.
2454  *
2455  * If the iowait structure is non-NULL and not equal to the iowait list
2456  * the unprocessed part of the list  will be appended to the list in wait.
2457  *
2458  * In all cases, the tx_list will be updated so the head of the tx_list is
2459  * the list of descriptors that have yet to be transmitted.
2460  *
2461  * The intent of this call is to provide a more efficient
2462  * way of submitting multiple packets to SDMA while holding the tail
2463  * side locking.
2464  *
2465  * Return:
2466  * 0 - Success,
2467  * -EINVAL - sdma_txreq incomplete, -EBUSY - no space in ring (wait == NULL)
2468  * -EIOCBQUEUED - tx queued to iowait, -ECOMM bad sdma state
2469  */
2470 int sdma_send_txlist(struct sdma_engine *sde, struct iowait *wait,
2471 		     struct list_head *tx_list, u32 *count_out)
2472 {
2473 	struct sdma_txreq *tx, *tx_next;
2474 	int ret = 0;
2475 	unsigned long flags;
2476 	u16 tail = INVALID_TAIL;
2477 	u32 submit_count = 0, flush_count = 0, total_count;
2478 
2479 	spin_lock_irqsave(&sde->tail_lock, flags);
2480 retry:
2481 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2482 		tx->wait = wait;
2483 		if (unlikely(!__sdma_running(sde)))
2484 			goto unlock_noconn;
2485 		if (unlikely(tx->num_desc > sde->desc_avail))
2486 			goto nodesc;
2487 		if (unlikely(tx->tlen)) {
2488 			ret = -EINVAL;
2489 			goto update_tail;
2490 		}
2491 		list_del_init(&tx->list);
2492 		tail = submit_tx(sde, tx);
2493 		submit_count++;
2494 		if (tail != INVALID_TAIL &&
2495 		    (submit_count & SDMA_TAIL_UPDATE_THRESH) == 0) {
2496 			sdma_update_tail(sde, tail);
2497 			tail = INVALID_TAIL;
2498 		}
2499 	}
2500 update_tail:
2501 	total_count = submit_count + flush_count;
2502 	if (wait) {
2503 		iowait_sdma_add(wait, total_count);
2504 		iowait_starve_clear(submit_count > 0, wait);
2505 	}
2506 	if (tail != INVALID_TAIL)
2507 		sdma_update_tail(sde, tail);
2508 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2509 	*count_out = total_count;
2510 	return ret;
2511 unlock_noconn:
2512 	spin_lock(&sde->flushlist_lock);
2513 	list_for_each_entry_safe(tx, tx_next, tx_list, list) {
2514 		tx->wait = wait;
2515 		list_del_init(&tx->list);
2516 		tx->next_descq_idx = 0;
2517 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
2518 		tx->sn = sde->tail_sn++;
2519 		trace_hfi1_sdma_in_sn(sde, tx->sn);
2520 #endif
2521 		list_add_tail(&tx->list, &sde->flushlist);
2522 		flush_count++;
2523 		if (wait) {
2524 			wait->tx_count++;
2525 			wait->count += tx->num_desc;
2526 		}
2527 	}
2528 	spin_unlock(&sde->flushlist_lock);
2529 	schedule_work(&sde->flush_worker);
2530 	ret = -ECOMM;
2531 	goto update_tail;
2532 nodesc:
2533 	ret = sdma_check_progress(sde, wait, tx, submit_count > 0);
2534 	if (ret == -EAGAIN) {
2535 		ret = 0;
2536 		goto retry;
2537 	}
2538 	sde->descq_full_count++;
2539 	goto update_tail;
2540 }
2541 
2542 static void sdma_process_event(struct sdma_engine *sde, enum sdma_events event)
2543 {
2544 	unsigned long flags;
2545 
2546 	spin_lock_irqsave(&sde->tail_lock, flags);
2547 	write_seqlock(&sde->head_lock);
2548 
2549 	__sdma_process_event(sde, event);
2550 
2551 	if (sde->state.current_state == sdma_state_s99_running)
2552 		sdma_desc_avail(sde, sdma_descq_freecnt(sde));
2553 
2554 	write_sequnlock(&sde->head_lock);
2555 	spin_unlock_irqrestore(&sde->tail_lock, flags);
2556 }
2557 
2558 static void __sdma_process_event(struct sdma_engine *sde,
2559 				 enum sdma_events event)
2560 {
2561 	struct sdma_state *ss = &sde->state;
2562 	int need_progress = 0;
2563 
2564 	/* CONFIG SDMA temporary */
2565 #ifdef CONFIG_SDMA_VERBOSITY
2566 	dd_dev_err(sde->dd, "CONFIG SDMA(%u) [%s] %s\n", sde->this_idx,
2567 		   sdma_state_names[ss->current_state],
2568 		   sdma_event_names[event]);
2569 #endif
2570 
2571 	switch (ss->current_state) {
2572 	case sdma_state_s00_hw_down:
2573 		switch (event) {
2574 		case sdma_event_e00_go_hw_down:
2575 			break;
2576 		case sdma_event_e30_go_running:
2577 			/*
2578 			 * If down, but running requested (usually result
2579 			 * of link up, then we need to start up.
2580 			 * This can happen when hw down is requested while
2581 			 * bringing the link up with traffic active on
2582 			 * 7220, e.g.
2583 			 */
2584 			ss->go_s99_running = 1;
2585 			/* fall through -- and start dma engine */
2586 		case sdma_event_e10_go_hw_start:
2587 			/* This reference means the state machine is started */
2588 			sdma_get(&sde->state);
2589 			sdma_set_state(sde,
2590 				       sdma_state_s10_hw_start_up_halt_wait);
2591 			break;
2592 		case sdma_event_e15_hw_halt_done:
2593 			break;
2594 		case sdma_event_e25_hw_clean_up_done:
2595 			break;
2596 		case sdma_event_e40_sw_cleaned:
2597 			sdma_sw_tear_down(sde);
2598 			break;
2599 		case sdma_event_e50_hw_cleaned:
2600 			break;
2601 		case sdma_event_e60_hw_halted:
2602 			break;
2603 		case sdma_event_e70_go_idle:
2604 			break;
2605 		case sdma_event_e80_hw_freeze:
2606 			break;
2607 		case sdma_event_e81_hw_frozen:
2608 			break;
2609 		case sdma_event_e82_hw_unfreeze:
2610 			break;
2611 		case sdma_event_e85_link_down:
2612 			break;
2613 		case sdma_event_e90_sw_halted:
2614 			break;
2615 		}
2616 		break;
2617 
2618 	case sdma_state_s10_hw_start_up_halt_wait:
2619 		switch (event) {
2620 		case sdma_event_e00_go_hw_down:
2621 			sdma_set_state(sde, sdma_state_s00_hw_down);
2622 			sdma_sw_tear_down(sde);
2623 			break;
2624 		case sdma_event_e10_go_hw_start:
2625 			break;
2626 		case sdma_event_e15_hw_halt_done:
2627 			sdma_set_state(sde,
2628 				       sdma_state_s15_hw_start_up_clean_wait);
2629 			sdma_start_hw_clean_up(sde);
2630 			break;
2631 		case sdma_event_e25_hw_clean_up_done:
2632 			break;
2633 		case sdma_event_e30_go_running:
2634 			ss->go_s99_running = 1;
2635 			break;
2636 		case sdma_event_e40_sw_cleaned:
2637 			break;
2638 		case sdma_event_e50_hw_cleaned:
2639 			break;
2640 		case sdma_event_e60_hw_halted:
2641 			schedule_work(&sde->err_halt_worker);
2642 			break;
2643 		case sdma_event_e70_go_idle:
2644 			ss->go_s99_running = 0;
2645 			break;
2646 		case sdma_event_e80_hw_freeze:
2647 			break;
2648 		case sdma_event_e81_hw_frozen:
2649 			break;
2650 		case sdma_event_e82_hw_unfreeze:
2651 			break;
2652 		case sdma_event_e85_link_down:
2653 			break;
2654 		case sdma_event_e90_sw_halted:
2655 			break;
2656 		}
2657 		break;
2658 
2659 	case sdma_state_s15_hw_start_up_clean_wait:
2660 		switch (event) {
2661 		case sdma_event_e00_go_hw_down:
2662 			sdma_set_state(sde, sdma_state_s00_hw_down);
2663 			sdma_sw_tear_down(sde);
2664 			break;
2665 		case sdma_event_e10_go_hw_start:
2666 			break;
2667 		case sdma_event_e15_hw_halt_done:
2668 			break;
2669 		case sdma_event_e25_hw_clean_up_done:
2670 			sdma_hw_start_up(sde);
2671 			sdma_set_state(sde, ss->go_s99_running ?
2672 				       sdma_state_s99_running :
2673 				       sdma_state_s20_idle);
2674 			break;
2675 		case sdma_event_e30_go_running:
2676 			ss->go_s99_running = 1;
2677 			break;
2678 		case sdma_event_e40_sw_cleaned:
2679 			break;
2680 		case sdma_event_e50_hw_cleaned:
2681 			break;
2682 		case sdma_event_e60_hw_halted:
2683 			break;
2684 		case sdma_event_e70_go_idle:
2685 			ss->go_s99_running = 0;
2686 			break;
2687 		case sdma_event_e80_hw_freeze:
2688 			break;
2689 		case sdma_event_e81_hw_frozen:
2690 			break;
2691 		case sdma_event_e82_hw_unfreeze:
2692 			break;
2693 		case sdma_event_e85_link_down:
2694 			break;
2695 		case sdma_event_e90_sw_halted:
2696 			break;
2697 		}
2698 		break;
2699 
2700 	case sdma_state_s20_idle:
2701 		switch (event) {
2702 		case sdma_event_e00_go_hw_down:
2703 			sdma_set_state(sde, sdma_state_s00_hw_down);
2704 			sdma_sw_tear_down(sde);
2705 			break;
2706 		case sdma_event_e10_go_hw_start:
2707 			break;
2708 		case sdma_event_e15_hw_halt_done:
2709 			break;
2710 		case sdma_event_e25_hw_clean_up_done:
2711 			break;
2712 		case sdma_event_e30_go_running:
2713 			sdma_set_state(sde, sdma_state_s99_running);
2714 			ss->go_s99_running = 1;
2715 			break;
2716 		case sdma_event_e40_sw_cleaned:
2717 			break;
2718 		case sdma_event_e50_hw_cleaned:
2719 			break;
2720 		case sdma_event_e60_hw_halted:
2721 			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
2722 			schedule_work(&sde->err_halt_worker);
2723 			break;
2724 		case sdma_event_e70_go_idle:
2725 			break;
2726 		case sdma_event_e85_link_down:
2727 			/* fall through */
2728 		case sdma_event_e80_hw_freeze:
2729 			sdma_set_state(sde, sdma_state_s80_hw_freeze);
2730 			atomic_dec(&sde->dd->sdma_unfreeze_count);
2731 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2732 			break;
2733 		case sdma_event_e81_hw_frozen:
2734 			break;
2735 		case sdma_event_e82_hw_unfreeze:
2736 			break;
2737 		case sdma_event_e90_sw_halted:
2738 			break;
2739 		}
2740 		break;
2741 
2742 	case sdma_state_s30_sw_clean_up_wait:
2743 		switch (event) {
2744 		case sdma_event_e00_go_hw_down:
2745 			sdma_set_state(sde, sdma_state_s00_hw_down);
2746 			break;
2747 		case sdma_event_e10_go_hw_start:
2748 			break;
2749 		case sdma_event_e15_hw_halt_done:
2750 			break;
2751 		case sdma_event_e25_hw_clean_up_done:
2752 			break;
2753 		case sdma_event_e30_go_running:
2754 			ss->go_s99_running = 1;
2755 			break;
2756 		case sdma_event_e40_sw_cleaned:
2757 			sdma_set_state(sde, sdma_state_s40_hw_clean_up_wait);
2758 			sdma_start_hw_clean_up(sde);
2759 			break;
2760 		case sdma_event_e50_hw_cleaned:
2761 			break;
2762 		case sdma_event_e60_hw_halted:
2763 			break;
2764 		case sdma_event_e70_go_idle:
2765 			ss->go_s99_running = 0;
2766 			break;
2767 		case sdma_event_e80_hw_freeze:
2768 			break;
2769 		case sdma_event_e81_hw_frozen:
2770 			break;
2771 		case sdma_event_e82_hw_unfreeze:
2772 			break;
2773 		case sdma_event_e85_link_down:
2774 			ss->go_s99_running = 0;
2775 			break;
2776 		case sdma_event_e90_sw_halted:
2777 			break;
2778 		}
2779 		break;
2780 
2781 	case sdma_state_s40_hw_clean_up_wait:
2782 		switch (event) {
2783 		case sdma_event_e00_go_hw_down:
2784 			sdma_set_state(sde, sdma_state_s00_hw_down);
2785 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2786 			break;
2787 		case sdma_event_e10_go_hw_start:
2788 			break;
2789 		case sdma_event_e15_hw_halt_done:
2790 			break;
2791 		case sdma_event_e25_hw_clean_up_done:
2792 			sdma_hw_start_up(sde);
2793 			sdma_set_state(sde, ss->go_s99_running ?
2794 				       sdma_state_s99_running :
2795 				       sdma_state_s20_idle);
2796 			break;
2797 		case sdma_event_e30_go_running:
2798 			ss->go_s99_running = 1;
2799 			break;
2800 		case sdma_event_e40_sw_cleaned:
2801 			break;
2802 		case sdma_event_e50_hw_cleaned:
2803 			break;
2804 		case sdma_event_e60_hw_halted:
2805 			break;
2806 		case sdma_event_e70_go_idle:
2807 			ss->go_s99_running = 0;
2808 			break;
2809 		case sdma_event_e80_hw_freeze:
2810 			break;
2811 		case sdma_event_e81_hw_frozen:
2812 			break;
2813 		case sdma_event_e82_hw_unfreeze:
2814 			break;
2815 		case sdma_event_e85_link_down:
2816 			ss->go_s99_running = 0;
2817 			break;
2818 		case sdma_event_e90_sw_halted:
2819 			break;
2820 		}
2821 		break;
2822 
2823 	case sdma_state_s50_hw_halt_wait:
2824 		switch (event) {
2825 		case sdma_event_e00_go_hw_down:
2826 			sdma_set_state(sde, sdma_state_s00_hw_down);
2827 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2828 			break;
2829 		case sdma_event_e10_go_hw_start:
2830 			break;
2831 		case sdma_event_e15_hw_halt_done:
2832 			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2833 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2834 			break;
2835 		case sdma_event_e25_hw_clean_up_done:
2836 			break;
2837 		case sdma_event_e30_go_running:
2838 			ss->go_s99_running = 1;
2839 			break;
2840 		case sdma_event_e40_sw_cleaned:
2841 			break;
2842 		case sdma_event_e50_hw_cleaned:
2843 			break;
2844 		case sdma_event_e60_hw_halted:
2845 			schedule_work(&sde->err_halt_worker);
2846 			break;
2847 		case sdma_event_e70_go_idle:
2848 			ss->go_s99_running = 0;
2849 			break;
2850 		case sdma_event_e80_hw_freeze:
2851 			break;
2852 		case sdma_event_e81_hw_frozen:
2853 			break;
2854 		case sdma_event_e82_hw_unfreeze:
2855 			break;
2856 		case sdma_event_e85_link_down:
2857 			ss->go_s99_running = 0;
2858 			break;
2859 		case sdma_event_e90_sw_halted:
2860 			break;
2861 		}
2862 		break;
2863 
2864 	case sdma_state_s60_idle_halt_wait:
2865 		switch (event) {
2866 		case sdma_event_e00_go_hw_down:
2867 			sdma_set_state(sde, sdma_state_s00_hw_down);
2868 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2869 			break;
2870 		case sdma_event_e10_go_hw_start:
2871 			break;
2872 		case sdma_event_e15_hw_halt_done:
2873 			sdma_set_state(sde, sdma_state_s30_sw_clean_up_wait);
2874 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2875 			break;
2876 		case sdma_event_e25_hw_clean_up_done:
2877 			break;
2878 		case sdma_event_e30_go_running:
2879 			ss->go_s99_running = 1;
2880 			break;
2881 		case sdma_event_e40_sw_cleaned:
2882 			break;
2883 		case sdma_event_e50_hw_cleaned:
2884 			break;
2885 		case sdma_event_e60_hw_halted:
2886 			schedule_work(&sde->err_halt_worker);
2887 			break;
2888 		case sdma_event_e70_go_idle:
2889 			ss->go_s99_running = 0;
2890 			break;
2891 		case sdma_event_e80_hw_freeze:
2892 			break;
2893 		case sdma_event_e81_hw_frozen:
2894 			break;
2895 		case sdma_event_e82_hw_unfreeze:
2896 			break;
2897 		case sdma_event_e85_link_down:
2898 			break;
2899 		case sdma_event_e90_sw_halted:
2900 			break;
2901 		}
2902 		break;
2903 
2904 	case sdma_state_s80_hw_freeze:
2905 		switch (event) {
2906 		case sdma_event_e00_go_hw_down:
2907 			sdma_set_state(sde, sdma_state_s00_hw_down);
2908 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2909 			break;
2910 		case sdma_event_e10_go_hw_start:
2911 			break;
2912 		case sdma_event_e15_hw_halt_done:
2913 			break;
2914 		case sdma_event_e25_hw_clean_up_done:
2915 			break;
2916 		case sdma_event_e30_go_running:
2917 			ss->go_s99_running = 1;
2918 			break;
2919 		case sdma_event_e40_sw_cleaned:
2920 			break;
2921 		case sdma_event_e50_hw_cleaned:
2922 			break;
2923 		case sdma_event_e60_hw_halted:
2924 			break;
2925 		case sdma_event_e70_go_idle:
2926 			ss->go_s99_running = 0;
2927 			break;
2928 		case sdma_event_e80_hw_freeze:
2929 			break;
2930 		case sdma_event_e81_hw_frozen:
2931 			sdma_set_state(sde, sdma_state_s82_freeze_sw_clean);
2932 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2933 			break;
2934 		case sdma_event_e82_hw_unfreeze:
2935 			break;
2936 		case sdma_event_e85_link_down:
2937 			break;
2938 		case sdma_event_e90_sw_halted:
2939 			break;
2940 		}
2941 		break;
2942 
2943 	case sdma_state_s82_freeze_sw_clean:
2944 		switch (event) {
2945 		case sdma_event_e00_go_hw_down:
2946 			sdma_set_state(sde, sdma_state_s00_hw_down);
2947 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2948 			break;
2949 		case sdma_event_e10_go_hw_start:
2950 			break;
2951 		case sdma_event_e15_hw_halt_done:
2952 			break;
2953 		case sdma_event_e25_hw_clean_up_done:
2954 			break;
2955 		case sdma_event_e30_go_running:
2956 			ss->go_s99_running = 1;
2957 			break;
2958 		case sdma_event_e40_sw_cleaned:
2959 			/* notify caller this engine is done cleaning */
2960 			atomic_dec(&sde->dd->sdma_unfreeze_count);
2961 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
2962 			break;
2963 		case sdma_event_e50_hw_cleaned:
2964 			break;
2965 		case sdma_event_e60_hw_halted:
2966 			break;
2967 		case sdma_event_e70_go_idle:
2968 			ss->go_s99_running = 0;
2969 			break;
2970 		case sdma_event_e80_hw_freeze:
2971 			break;
2972 		case sdma_event_e81_hw_frozen:
2973 			break;
2974 		case sdma_event_e82_hw_unfreeze:
2975 			sdma_hw_start_up(sde);
2976 			sdma_set_state(sde, ss->go_s99_running ?
2977 				       sdma_state_s99_running :
2978 				       sdma_state_s20_idle);
2979 			break;
2980 		case sdma_event_e85_link_down:
2981 			break;
2982 		case sdma_event_e90_sw_halted:
2983 			break;
2984 		}
2985 		break;
2986 
2987 	case sdma_state_s99_running:
2988 		switch (event) {
2989 		case sdma_event_e00_go_hw_down:
2990 			sdma_set_state(sde, sdma_state_s00_hw_down);
2991 			tasklet_hi_schedule(&sde->sdma_sw_clean_up_task);
2992 			break;
2993 		case sdma_event_e10_go_hw_start:
2994 			break;
2995 		case sdma_event_e15_hw_halt_done:
2996 			break;
2997 		case sdma_event_e25_hw_clean_up_done:
2998 			break;
2999 		case sdma_event_e30_go_running:
3000 			break;
3001 		case sdma_event_e40_sw_cleaned:
3002 			break;
3003 		case sdma_event_e50_hw_cleaned:
3004 			break;
3005 		case sdma_event_e60_hw_halted:
3006 			need_progress = 1;
3007 			sdma_err_progress_check_schedule(sde);
3008 			/* fall through */
3009 		case sdma_event_e90_sw_halted:
3010 			/*
3011 			* SW initiated halt does not perform engines
3012 			* progress check
3013 			*/
3014 			sdma_set_state(sde, sdma_state_s50_hw_halt_wait);
3015 			schedule_work(&sde->err_halt_worker);
3016 			break;
3017 		case sdma_event_e70_go_idle:
3018 			sdma_set_state(sde, sdma_state_s60_idle_halt_wait);
3019 			break;
3020 		case sdma_event_e85_link_down:
3021 			ss->go_s99_running = 0;
3022 			/* fall through */
3023 		case sdma_event_e80_hw_freeze:
3024 			sdma_set_state(sde, sdma_state_s80_hw_freeze);
3025 			atomic_dec(&sde->dd->sdma_unfreeze_count);
3026 			wake_up_interruptible(&sde->dd->sdma_unfreeze_wq);
3027 			break;
3028 		case sdma_event_e81_hw_frozen:
3029 			break;
3030 		case sdma_event_e82_hw_unfreeze:
3031 			break;
3032 		}
3033 		break;
3034 	}
3035 
3036 	ss->last_event = event;
3037 	if (need_progress)
3038 		sdma_make_progress(sde, 0);
3039 }
3040 
3041 /*
3042  * _extend_sdma_tx_descs() - helper to extend txreq
3043  *
3044  * This is called once the initial nominal allocation
3045  * of descriptors in the sdma_txreq is exhausted.
3046  *
3047  * The code will bump the allocation up to the max
3048  * of MAX_DESC (64) descriptors. There doesn't seem
3049  * much point in an interim step. The last descriptor
3050  * is reserved for coalesce buffer in order to support
3051  * cases where input packet has >MAX_DESC iovecs.
3052  *
3053  */
3054 static int _extend_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3055 {
3056 	int i;
3057 
3058 	/* Handle last descriptor */
3059 	if (unlikely((tx->num_desc == (MAX_DESC - 1)))) {
3060 		/* if tlen is 0, it is for padding, release last descriptor */
3061 		if (!tx->tlen) {
3062 			tx->desc_limit = MAX_DESC;
3063 		} else if (!tx->coalesce_buf) {
3064 			/* allocate coalesce buffer with space for padding */
3065 			tx->coalesce_buf = kmalloc(tx->tlen + sizeof(u32),
3066 						   GFP_ATOMIC);
3067 			if (!tx->coalesce_buf)
3068 				goto enomem;
3069 			tx->coalesce_idx = 0;
3070 		}
3071 		return 0;
3072 	}
3073 
3074 	if (unlikely(tx->num_desc == MAX_DESC))
3075 		goto enomem;
3076 
3077 	tx->descp = kmalloc_array(
3078 			MAX_DESC,
3079 			sizeof(struct sdma_desc),
3080 			GFP_ATOMIC);
3081 	if (!tx->descp)
3082 		goto enomem;
3083 
3084 	/* reserve last descriptor for coalescing */
3085 	tx->desc_limit = MAX_DESC - 1;
3086 	/* copy ones already built */
3087 	for (i = 0; i < tx->num_desc; i++)
3088 		tx->descp[i] = tx->descs[i];
3089 	return 0;
3090 enomem:
3091 	__sdma_txclean(dd, tx);
3092 	return -ENOMEM;
3093 }
3094 
3095 /*
3096  * ext_coal_sdma_tx_descs() - extend or coalesce sdma tx descriptors
3097  *
3098  * This is called once the initial nominal allocation of descriptors
3099  * in the sdma_txreq is exhausted.
3100  *
3101  * This function calls _extend_sdma_tx_descs to extend or allocate
3102  * coalesce buffer. If there is a allocated coalesce buffer, it will
3103  * copy the input packet data into the coalesce buffer. It also adds
3104  * coalesce buffer descriptor once when whole packet is received.
3105  *
3106  * Return:
3107  * <0 - error
3108  * 0 - coalescing, don't populate descriptor
3109  * 1 - continue with populating descriptor
3110  */
3111 int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
3112 			   int type, void *kvaddr, struct page *page,
3113 			   unsigned long offset, u16 len)
3114 {
3115 	int pad_len, rval;
3116 	dma_addr_t addr;
3117 
3118 	rval = _extend_sdma_tx_descs(dd, tx);
3119 	if (rval) {
3120 		__sdma_txclean(dd, tx);
3121 		return rval;
3122 	}
3123 
3124 	/* If coalesce buffer is allocated, copy data into it */
3125 	if (tx->coalesce_buf) {
3126 		if (type == SDMA_MAP_NONE) {
3127 			__sdma_txclean(dd, tx);
3128 			return -EINVAL;
3129 		}
3130 
3131 		if (type == SDMA_MAP_PAGE) {
3132 			kvaddr = kmap(page);
3133 			kvaddr += offset;
3134 		} else if (WARN_ON(!kvaddr)) {
3135 			__sdma_txclean(dd, tx);
3136 			return -EINVAL;
3137 		}
3138 
3139 		memcpy(tx->coalesce_buf + tx->coalesce_idx, kvaddr, len);
3140 		tx->coalesce_idx += len;
3141 		if (type == SDMA_MAP_PAGE)
3142 			kunmap(page);
3143 
3144 		/* If there is more data, return */
3145 		if (tx->tlen - tx->coalesce_idx)
3146 			return 0;
3147 
3148 		/* Whole packet is received; add any padding */
3149 		pad_len = tx->packet_len & (sizeof(u32) - 1);
3150 		if (pad_len) {
3151 			pad_len = sizeof(u32) - pad_len;
3152 			memset(tx->coalesce_buf + tx->coalesce_idx, 0, pad_len);
3153 			/* padding is taken care of for coalescing case */
3154 			tx->packet_len += pad_len;
3155 			tx->tlen += pad_len;
3156 		}
3157 
3158 		/* dma map the coalesce buffer */
3159 		addr = dma_map_single(&dd->pcidev->dev,
3160 				      tx->coalesce_buf,
3161 				      tx->tlen,
3162 				      DMA_TO_DEVICE);
3163 
3164 		if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
3165 			__sdma_txclean(dd, tx);
3166 			return -ENOSPC;
3167 		}
3168 
3169 		/* Add descriptor for coalesce buffer */
3170 		tx->desc_limit = MAX_DESC;
3171 		return _sdma_txadd_daddr(dd, SDMA_MAP_SINGLE, tx,
3172 					 addr, tx->tlen);
3173 	}
3174 
3175 	return 1;
3176 }
3177 
3178 /* Update sdes when the lmc changes */
3179 void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid)
3180 {
3181 	struct sdma_engine *sde;
3182 	int i;
3183 	u64 sreg;
3184 
3185 	sreg = ((mask & SD(CHECK_SLID_MASK_MASK)) <<
3186 		SD(CHECK_SLID_MASK_SHIFT)) |
3187 		(((lid & mask) & SD(CHECK_SLID_VALUE_MASK)) <<
3188 		SD(CHECK_SLID_VALUE_SHIFT));
3189 
3190 	for (i = 0; i < dd->num_sdma; i++) {
3191 		hfi1_cdbg(LINKVERB, "SendDmaEngine[%d].SLID_CHECK = 0x%x",
3192 			  i, (u32)sreg);
3193 		sde = &dd->per_sdma[i];
3194 		write_sde_csr(sde, SD(CHECK_SLID), sreg);
3195 	}
3196 }
3197 
3198 /* tx not dword sized - pad */
3199 int _pad_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx)
3200 {
3201 	int rval = 0;
3202 
3203 	tx->num_desc++;
3204 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
3205 		rval = _extend_sdma_tx_descs(dd, tx);
3206 		if (rval) {
3207 			__sdma_txclean(dd, tx);
3208 			return rval;
3209 		}
3210 	}
3211 	/* finish the one just added */
3212 	make_tx_sdma_desc(
3213 		tx,
3214 		SDMA_MAP_NONE,
3215 		dd->sdma_pad_phys,
3216 		sizeof(u32) - (tx->packet_len & (sizeof(u32) - 1)));
3217 	_sdma_close_tx(dd, tx);
3218 	return rval;
3219 }
3220 
3221 /*
3222  * Add ahg to the sdma_txreq
3223  *
3224  * The logic will consume up to 3
3225  * descriptors at the beginning of
3226  * sdma_txreq.
3227  */
3228 void _sdma_txreq_ahgadd(
3229 	struct sdma_txreq *tx,
3230 	u8 num_ahg,
3231 	u8 ahg_entry,
3232 	u32 *ahg,
3233 	u8 ahg_hlen)
3234 {
3235 	u32 i, shift = 0, desc = 0;
3236 	u8 mode;
3237 
3238 	WARN_ON_ONCE(num_ahg > 9 || (ahg_hlen & 3) || ahg_hlen == 4);
3239 	/* compute mode */
3240 	if (num_ahg == 1)
3241 		mode = SDMA_AHG_APPLY_UPDATE1;
3242 	else if (num_ahg <= 5)
3243 		mode = SDMA_AHG_APPLY_UPDATE2;
3244 	else
3245 		mode = SDMA_AHG_APPLY_UPDATE3;
3246 	tx->num_desc++;
3247 	/* initialize to consumed descriptors to zero */
3248 	switch (mode) {
3249 	case SDMA_AHG_APPLY_UPDATE3:
3250 		tx->num_desc++;
3251 		tx->descs[2].qw[0] = 0;
3252 		tx->descs[2].qw[1] = 0;
3253 		/* FALLTHROUGH */
3254 	case SDMA_AHG_APPLY_UPDATE2:
3255 		tx->num_desc++;
3256 		tx->descs[1].qw[0] = 0;
3257 		tx->descs[1].qw[1] = 0;
3258 		break;
3259 	}
3260 	ahg_hlen >>= 2;
3261 	tx->descs[0].qw[1] |=
3262 		(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
3263 			<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
3264 		(((u64)ahg_hlen & SDMA_DESC1_HEADER_DWS_MASK)
3265 			<< SDMA_DESC1_HEADER_DWS_SHIFT) |
3266 		(((u64)mode & SDMA_DESC1_HEADER_MODE_MASK)
3267 			<< SDMA_DESC1_HEADER_MODE_SHIFT) |
3268 		(((u64)ahg[0] & SDMA_DESC1_HEADER_UPDATE1_MASK)
3269 			<< SDMA_DESC1_HEADER_UPDATE1_SHIFT);
3270 	for (i = 0; i < (num_ahg - 1); i++) {
3271 		if (!shift && !(i & 2))
3272 			desc++;
3273 		tx->descs[desc].qw[!!(i & 2)] |=
3274 			(((u64)ahg[i + 1])
3275 				<< shift);
3276 		shift = (shift + 32) & 63;
3277 	}
3278 }
3279 
3280 /**
3281  * sdma_ahg_alloc - allocate an AHG entry
3282  * @sde: engine to allocate from
3283  *
3284  * Return:
3285  * 0-31 when successful, -EOPNOTSUPP if AHG is not enabled,
3286  * -ENOSPC if an entry is not available
3287  */
3288 int sdma_ahg_alloc(struct sdma_engine *sde)
3289 {
3290 	int nr;
3291 	int oldbit;
3292 
3293 	if (!sde) {
3294 		trace_hfi1_ahg_allocate(sde, -EINVAL);
3295 		return -EINVAL;
3296 	}
3297 	while (1) {
3298 		nr = ffz(READ_ONCE(sde->ahg_bits));
3299 		if (nr > 31) {
3300 			trace_hfi1_ahg_allocate(sde, -ENOSPC);
3301 			return -ENOSPC;
3302 		}
3303 		oldbit = test_and_set_bit(nr, &sde->ahg_bits);
3304 		if (!oldbit)
3305 			break;
3306 		cpu_relax();
3307 	}
3308 	trace_hfi1_ahg_allocate(sde, nr);
3309 	return nr;
3310 }
3311 
3312 /**
3313  * sdma_ahg_free - free an AHG entry
3314  * @sde: engine to return AHG entry
3315  * @ahg_index: index to free
3316  *
3317  * This routine frees the indicate AHG entry.
3318  */
3319 void sdma_ahg_free(struct sdma_engine *sde, int ahg_index)
3320 {
3321 	if (!sde)
3322 		return;
3323 	trace_hfi1_ahg_deallocate(sde, ahg_index);
3324 	if (ahg_index < 0 || ahg_index > 31)
3325 		return;
3326 	clear_bit(ahg_index, &sde->ahg_bits);
3327 }
3328 
3329 /*
3330  * SPC freeze handling for SDMA engines.  Called when the driver knows
3331  * the SPC is going into a freeze but before the freeze is fully
3332  * settled.  Generally an error interrupt.
3333  *
3334  * This event will pull the engine out of running so no more entries can be
3335  * added to the engine's queue.
3336  */
3337 void sdma_freeze_notify(struct hfi1_devdata *dd, int link_down)
3338 {
3339 	int i;
3340 	enum sdma_events event = link_down ? sdma_event_e85_link_down :
3341 					     sdma_event_e80_hw_freeze;
3342 
3343 	/* set up the wait but do not wait here */
3344 	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3345 
3346 	/* tell all engines to stop running and wait */
3347 	for (i = 0; i < dd->num_sdma; i++)
3348 		sdma_process_event(&dd->per_sdma[i], event);
3349 
3350 	/* sdma_freeze() will wait for all engines to have stopped */
3351 }
3352 
3353 /*
3354  * SPC freeze handling for SDMA engines.  Called when the driver knows
3355  * the SPC is fully frozen.
3356  */
3357 void sdma_freeze(struct hfi1_devdata *dd)
3358 {
3359 	int i;
3360 	int ret;
3361 
3362 	/*
3363 	 * Make sure all engines have moved out of the running state before
3364 	 * continuing.
3365 	 */
3366 	ret = wait_event_interruptible(dd->sdma_unfreeze_wq,
3367 				       atomic_read(&dd->sdma_unfreeze_count) <=
3368 				       0);
3369 	/* interrupted or count is negative, then unloading - just exit */
3370 	if (ret || atomic_read(&dd->sdma_unfreeze_count) < 0)
3371 		return;
3372 
3373 	/* set up the count for the next wait */
3374 	atomic_set(&dd->sdma_unfreeze_count, dd->num_sdma);
3375 
3376 	/* tell all engines that the SPC is frozen, they can start cleaning */
3377 	for (i = 0; i < dd->num_sdma; i++)
3378 		sdma_process_event(&dd->per_sdma[i], sdma_event_e81_hw_frozen);
3379 
3380 	/*
3381 	 * Wait for everyone to finish software clean before exiting.  The
3382 	 * software clean will read engine CSRs, so must be completed before
3383 	 * the next step, which will clear the engine CSRs.
3384 	 */
3385 	(void)wait_event_interruptible(dd->sdma_unfreeze_wq,
3386 				atomic_read(&dd->sdma_unfreeze_count) <= 0);
3387 	/* no need to check results - done no matter what */
3388 }
3389 
3390 /*
3391  * SPC freeze handling for the SDMA engines.  Called after the SPC is unfrozen.
3392  *
3393  * The SPC freeze acts like a SDMA halt and a hardware clean combined.  All
3394  * that is left is a software clean.  We could do it after the SPC is fully
3395  * frozen, but then we'd have to add another state to wait for the unfreeze.
3396  * Instead, just defer the software clean until the unfreeze step.
3397  */
3398 void sdma_unfreeze(struct hfi1_devdata *dd)
3399 {
3400 	int i;
3401 
3402 	/* tell all engines start freeze clean up */
3403 	for (i = 0; i < dd->num_sdma; i++)
3404 		sdma_process_event(&dd->per_sdma[i],
3405 				   sdma_event_e82_hw_unfreeze);
3406 }
3407 
3408 /**
3409  * _sdma_engine_progress_schedule() - schedule progress on engine
3410  * @sde: sdma_engine to schedule progress
3411  *
3412  */
3413 void _sdma_engine_progress_schedule(
3414 	struct sdma_engine *sde)
3415 {
3416 	trace_hfi1_sdma_engine_progress(sde, sde->progress_mask);
3417 	/* assume we have selected a good cpu */
3418 	write_csr(sde->dd,
3419 		  CCE_INT_FORCE + (8 * (IS_SDMA_START / 64)),
3420 		  sde->progress_mask);
3421 }
3422