xref: /openbmc/linux/drivers/infiniband/hw/hfi1/sdma.h (revision efe4a1ac)
1 #ifndef _HFI1_SDMA_H
2 #define _HFI1_SDMA_H
3 /*
4  * Copyright(c) 2015, 2016 Intel Corporation.
5  *
6  * This file is provided under a dual BSD/GPLv2 license.  When using or
7  * redistributing this file, you may do so under either license.
8  *
9  * GPL LICENSE SUMMARY
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of version 2 of the GNU General Public License as
13  * published by the Free Software Foundation.
14  *
15  * This program is distributed in the hope that it will be useful, but
16  * WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * BSD LICENSE
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  *
26  *  - Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  *  - Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in
30  *    the documentation and/or other materials provided with the
31  *    distribution.
32  *  - Neither the name of Intel Corporation nor the names of its
33  *    contributors may be used to endorse or promote products derived
34  *    from this software without specific prior written permission.
35  *
36  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
37  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
38  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
39  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
40  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
42  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
43  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
44  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
45  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
46  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
47  *
48  */
49 
50 #include <linux/types.h>
51 #include <linux/list.h>
52 #include <asm/byteorder.h>
53 #include <linux/workqueue.h>
54 #include <linux/rculist.h>
55 
56 #include "hfi.h"
57 #include "verbs.h"
58 #include "sdma_txreq.h"
59 
60 /* Hardware limit */
61 #define MAX_DESC 64
62 /* Hardware limit for SDMA packet size */
63 #define MAX_SDMA_PKT_SIZE ((16 * 1024) - 1)
64 
65 #define SDMA_TXREQ_S_OK        0
66 #define SDMA_TXREQ_S_SENDERROR 1
67 #define SDMA_TXREQ_S_ABORTED   2
68 #define SDMA_TXREQ_S_SHUTDOWN  3
69 
70 /* flags bits */
71 #define SDMA_TXREQ_F_URGENT       0x0001
72 #define SDMA_TXREQ_F_AHG_COPY     0x0002
73 #define SDMA_TXREQ_F_USE_AHG      0x0004
74 
75 #define SDMA_MAP_NONE          0
76 #define SDMA_MAP_SINGLE        1
77 #define SDMA_MAP_PAGE          2
78 
79 #define SDMA_AHG_VALUE_MASK          0xffff
80 #define SDMA_AHG_VALUE_SHIFT         0
81 #define SDMA_AHG_INDEX_MASK          0xf
82 #define SDMA_AHG_INDEX_SHIFT         16
83 #define SDMA_AHG_FIELD_LEN_MASK      0xf
84 #define SDMA_AHG_FIELD_LEN_SHIFT     20
85 #define SDMA_AHG_FIELD_START_MASK    0x1f
86 #define SDMA_AHG_FIELD_START_SHIFT   24
87 #define SDMA_AHG_UPDATE_ENABLE_MASK  0x1
88 #define SDMA_AHG_UPDATE_ENABLE_SHIFT 31
89 
90 /* AHG modes */
91 
92 /*
93  * Be aware the ordering and values
94  * for SDMA_AHG_APPLY_UPDATE[123]
95  * are assumed in generating a skip
96  * count in submit_tx() in sdma.c
97  */
98 #define SDMA_AHG_NO_AHG              0
99 #define SDMA_AHG_COPY                1
100 #define SDMA_AHG_APPLY_UPDATE1       2
101 #define SDMA_AHG_APPLY_UPDATE2       3
102 #define SDMA_AHG_APPLY_UPDATE3       4
103 
104 /*
105  * Bits defined in the send DMA descriptor.
106  */
107 #define SDMA_DESC0_FIRST_DESC_FLAG      BIT_ULL(63)
108 #define SDMA_DESC0_LAST_DESC_FLAG       BIT_ULL(62)
109 #define SDMA_DESC0_BYTE_COUNT_SHIFT     48
110 #define SDMA_DESC0_BYTE_COUNT_WIDTH     14
111 #define SDMA_DESC0_BYTE_COUNT_MASK \
112 	((1ULL << SDMA_DESC0_BYTE_COUNT_WIDTH) - 1)
113 #define SDMA_DESC0_BYTE_COUNT_SMASK \
114 	(SDMA_DESC0_BYTE_COUNT_MASK << SDMA_DESC0_BYTE_COUNT_SHIFT)
115 #define SDMA_DESC0_PHY_ADDR_SHIFT       0
116 #define SDMA_DESC0_PHY_ADDR_WIDTH       48
117 #define SDMA_DESC0_PHY_ADDR_MASK \
118 	((1ULL << SDMA_DESC0_PHY_ADDR_WIDTH) - 1)
119 #define SDMA_DESC0_PHY_ADDR_SMASK \
120 	(SDMA_DESC0_PHY_ADDR_MASK << SDMA_DESC0_PHY_ADDR_SHIFT)
121 
122 #define SDMA_DESC1_HEADER_UPDATE1_SHIFT 32
123 #define SDMA_DESC1_HEADER_UPDATE1_WIDTH 32
124 #define SDMA_DESC1_HEADER_UPDATE1_MASK \
125 	((1ULL << SDMA_DESC1_HEADER_UPDATE1_WIDTH) - 1)
126 #define SDMA_DESC1_HEADER_UPDATE1_SMASK \
127 	(SDMA_DESC1_HEADER_UPDATE1_MASK << SDMA_DESC1_HEADER_UPDATE1_SHIFT)
128 #define SDMA_DESC1_HEADER_MODE_SHIFT    13
129 #define SDMA_DESC1_HEADER_MODE_WIDTH    3
130 #define SDMA_DESC1_HEADER_MODE_MASK \
131 	((1ULL << SDMA_DESC1_HEADER_MODE_WIDTH) - 1)
132 #define SDMA_DESC1_HEADER_MODE_SMASK \
133 	(SDMA_DESC1_HEADER_MODE_MASK << SDMA_DESC1_HEADER_MODE_SHIFT)
134 #define SDMA_DESC1_HEADER_INDEX_SHIFT   8
135 #define SDMA_DESC1_HEADER_INDEX_WIDTH   5
136 #define SDMA_DESC1_HEADER_INDEX_MASK \
137 	((1ULL << SDMA_DESC1_HEADER_INDEX_WIDTH) - 1)
138 #define SDMA_DESC1_HEADER_INDEX_SMASK \
139 	(SDMA_DESC1_HEADER_INDEX_MASK << SDMA_DESC1_HEADER_INDEX_SHIFT)
140 #define SDMA_DESC1_HEADER_DWS_SHIFT     4
141 #define SDMA_DESC1_HEADER_DWS_WIDTH     4
142 #define SDMA_DESC1_HEADER_DWS_MASK \
143 	((1ULL << SDMA_DESC1_HEADER_DWS_WIDTH) - 1)
144 #define SDMA_DESC1_HEADER_DWS_SMASK \
145 	(SDMA_DESC1_HEADER_DWS_MASK << SDMA_DESC1_HEADER_DWS_SHIFT)
146 #define SDMA_DESC1_GENERATION_SHIFT     2
147 #define SDMA_DESC1_GENERATION_WIDTH     2
148 #define SDMA_DESC1_GENERATION_MASK \
149 	((1ULL << SDMA_DESC1_GENERATION_WIDTH) - 1)
150 #define SDMA_DESC1_GENERATION_SMASK \
151 	(SDMA_DESC1_GENERATION_MASK << SDMA_DESC1_GENERATION_SHIFT)
152 #define SDMA_DESC1_INT_REQ_FLAG         BIT_ULL(1)
153 #define SDMA_DESC1_HEAD_TO_HOST_FLAG    BIT_ULL(0)
154 
155 enum sdma_states {
156 	sdma_state_s00_hw_down,
157 	sdma_state_s10_hw_start_up_halt_wait,
158 	sdma_state_s15_hw_start_up_clean_wait,
159 	sdma_state_s20_idle,
160 	sdma_state_s30_sw_clean_up_wait,
161 	sdma_state_s40_hw_clean_up_wait,
162 	sdma_state_s50_hw_halt_wait,
163 	sdma_state_s60_idle_halt_wait,
164 	sdma_state_s80_hw_freeze,
165 	sdma_state_s82_freeze_sw_clean,
166 	sdma_state_s99_running,
167 };
168 
169 enum sdma_events {
170 	sdma_event_e00_go_hw_down,
171 	sdma_event_e10_go_hw_start,
172 	sdma_event_e15_hw_halt_done,
173 	sdma_event_e25_hw_clean_up_done,
174 	sdma_event_e30_go_running,
175 	sdma_event_e40_sw_cleaned,
176 	sdma_event_e50_hw_cleaned,
177 	sdma_event_e60_hw_halted,
178 	sdma_event_e70_go_idle,
179 	sdma_event_e80_hw_freeze,
180 	sdma_event_e81_hw_frozen,
181 	sdma_event_e82_hw_unfreeze,
182 	sdma_event_e85_link_down,
183 	sdma_event_e90_sw_halted,
184 };
185 
186 struct sdma_set_state_action {
187 	unsigned op_enable:1;
188 	unsigned op_intenable:1;
189 	unsigned op_halt:1;
190 	unsigned op_cleanup:1;
191 	unsigned go_s99_running_tofalse:1;
192 	unsigned go_s99_running_totrue:1;
193 };
194 
195 struct sdma_state {
196 	struct kref          kref;
197 	struct completion    comp;
198 	enum sdma_states current_state;
199 	unsigned             current_op;
200 	unsigned             go_s99_running;
201 	/* debugging/development */
202 	enum sdma_states previous_state;
203 	unsigned             previous_op;
204 	enum sdma_events last_event;
205 };
206 
207 /**
208  * DOC: sdma exported routines
209  *
210  * These sdma routines fit into three categories:
211  * - The SDMA API for building and submitting packets
212  *   to the ring
213  *
214  * - Initialization and tear down routines to buildup
215  *   and tear down SDMA
216  *
217  * - ISR entrances to handle interrupts, state changes
218  *   and errors
219  */
220 
221 /**
222  * DOC: sdma PSM/verbs API
223  *
224  * The sdma API is designed to be used by both PSM
225  * and verbs to supply packets to the SDMA ring.
226  *
227  * The usage of the API is as follows:
228  *
229  * Embed a struct iowait in the QP or
230  * PQ.  The iowait should be initialized with a
231  * call to iowait_init().
232  *
233  * The user of the API should create an allocation method
234  * for their version of the txreq. slabs, pre-allocated lists,
235  * and dma pools can be used.  Once the user's overload of
236  * the sdma_txreq has been allocated, the sdma_txreq member
237  * must be initialized with sdma_txinit() or sdma_txinit_ahg().
238  *
239  * The txreq must be declared with the sdma_txreq first.
240  *
241  * The tx request, once initialized,  is manipulated with calls to
242  * sdma_txadd_daddr(), sdma_txadd_page(), or sdma_txadd_kvaddr()
243  * for each disjoint memory location.  It is the user's responsibility
244  * to understand the packet boundaries and page boundaries to do the
245  * appropriate number of sdma_txadd_* calls..  The user
246  * must be prepared to deal with failures from these routines due to
247  * either memory allocation or dma_mapping failures.
248  *
249  * The mapping specifics for each memory location are recorded
250  * in the tx. Memory locations added with sdma_txadd_page()
251  * and sdma_txadd_kvaddr() are automatically mapped when added
252  * to the tx and nmapped as part of the progress processing in the
253  * SDMA interrupt handling.
254  *
255  * sdma_txadd_daddr() is used to add an dma_addr_t memory to the
256  * tx.   An example of a use case would be a pre-allocated
257  * set of headers allocated via dma_pool_alloc() or
258  * dma_alloc_coherent().  For these memory locations, it
259  * is the responsibility of the user to handle that unmapping.
260  * (This would usually be at an unload or job termination.)
261  *
262  * The routine sdma_send_txreq() is used to submit
263  * a tx to the ring after the appropriate number of
264  * sdma_txadd_* have been done.
265  *
266  * If it is desired to send a burst of sdma_txreqs, sdma_send_txlist()
267  * can be used to submit a list of packets.
268  *
269  * The user is free to use the link overhead in the struct sdma_txreq as
270  * long as the tx isn't in flight.
271  *
272  * The extreme degenerate case of the number of descriptors
273  * exceeding the ring size is automatically handled as
274  * memory locations are added.  An overflow of the descriptor
275  * array that is part of the sdma_txreq is also automatically
276  * handled.
277  *
278  */
279 
280 /**
281  * DOC: Infrastructure calls
282  *
283  * sdma_init() is used to initialize data structures and
284  * CSRs for the desired number of SDMA engines.
285  *
286  * sdma_start() is used to kick the SDMA engines initialized
287  * with sdma_init().   Interrupts must be enabled at this
288  * point since aspects of the state machine are interrupt
289  * driven.
290  *
291  * sdma_engine_error() and sdma_engine_interrupt() are
292  * entrances for interrupts.
293  *
294  * sdma_map_init() is for the management of the mapping
295  * table when the number of vls is changed.
296  *
297  */
298 
299 /*
300  * struct hw_sdma_desc - raw 128 bit SDMA descriptor
301  *
302  * This is the raw descriptor in the SDMA ring
303  */
304 struct hw_sdma_desc {
305 	/* private:  don't use directly */
306 	__le64 qw[2];
307 };
308 
309 /**
310  * struct sdma_engine - Data pertaining to each SDMA engine.
311  * @dd: a back-pointer to the device data
312  * @ppd: per port back-pointer
313  * @imask: mask for irq manipulation
314  * @idle_mask: mask for determining if an interrupt is due to sdma_idle
315  *
316  * This structure has the state for each sdma_engine.
317  *
318  * Accessing to non public fields are not supported
319  * since the private members are subject to change.
320  */
321 struct sdma_engine {
322 	/* read mostly */
323 	struct hfi1_devdata *dd;
324 	struct hfi1_pportdata *ppd;
325 	/* private: */
326 	void __iomem *tail_csr;
327 	u64 imask;			/* clear interrupt mask */
328 	u64 idle_mask;
329 	u64 progress_mask;
330 	u64 int_mask;
331 	/* private: */
332 	volatile __le64      *head_dma; /* DMA'ed by chip */
333 	/* private: */
334 	dma_addr_t            head_phys;
335 	/* private: */
336 	struct hw_sdma_desc *descq;
337 	/* private: */
338 	unsigned descq_full_count;
339 	struct sdma_txreq **tx_ring;
340 	/* private: */
341 	dma_addr_t            descq_phys;
342 	/* private */
343 	u32 sdma_mask;
344 	/* private */
345 	struct sdma_state state;
346 	/* private */
347 	int cpu;
348 	/* private: */
349 	u8 sdma_shift;
350 	/* private: */
351 	u8 this_idx; /* zero relative engine */
352 	/* protect changes to senddmactrl shadow */
353 	spinlock_t senddmactrl_lock;
354 	/* private: */
355 	u64 p_senddmactrl;		/* shadow per-engine SendDmaCtrl */
356 
357 	/* read/write using tail_lock */
358 	spinlock_t            tail_lock ____cacheline_aligned_in_smp;
359 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
360 	/* private: */
361 	u64                   tail_sn;
362 #endif
363 	/* private: */
364 	u32                   descq_tail;
365 	/* private: */
366 	unsigned long         ahg_bits;
367 	/* private: */
368 	u16                   desc_avail;
369 	/* private: */
370 	u16                   tx_tail;
371 	/* private: */
372 	u16 descq_cnt;
373 
374 	/* read/write using head_lock */
375 	/* private: */
376 	seqlock_t            head_lock ____cacheline_aligned_in_smp;
377 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
378 	/* private: */
379 	u64                   head_sn;
380 #endif
381 	/* private: */
382 	u32                   descq_head;
383 	/* private: */
384 	u16                   tx_head;
385 	/* private: */
386 	u64                   last_status;
387 	/* private */
388 	u64                     err_cnt;
389 	/* private */
390 	u64                     sdma_int_cnt;
391 	u64                     idle_int_cnt;
392 	u64                     progress_int_cnt;
393 
394 	/* private: */
395 	struct list_head      dmawait;
396 
397 	/* CONFIG SDMA for now, just blindly duplicate */
398 	/* private: */
399 	struct tasklet_struct sdma_hw_clean_up_task
400 		____cacheline_aligned_in_smp;
401 
402 	/* private: */
403 	struct tasklet_struct sdma_sw_clean_up_task
404 		____cacheline_aligned_in_smp;
405 	/* private: */
406 	struct work_struct err_halt_worker;
407 	/* private */
408 	struct timer_list     err_progress_check_timer;
409 	u32                   progress_check_head;
410 	/* private: */
411 	struct work_struct flush_worker;
412 	/* protect flush list */
413 	spinlock_t flushlist_lock;
414 	/* private: */
415 	struct list_head flushlist;
416 	struct cpumask cpu_mask;
417 	struct kobject kobj;
418 };
419 
420 int sdma_init(struct hfi1_devdata *dd, u8 port);
421 void sdma_start(struct hfi1_devdata *dd);
422 void sdma_exit(struct hfi1_devdata *dd);
423 void sdma_all_running(struct hfi1_devdata *dd);
424 void sdma_all_idle(struct hfi1_devdata *dd);
425 void sdma_freeze_notify(struct hfi1_devdata *dd, int go_idle);
426 void sdma_freeze(struct hfi1_devdata *dd);
427 void sdma_unfreeze(struct hfi1_devdata *dd);
428 void sdma_wait(struct hfi1_devdata *dd);
429 
430 /**
431  * sdma_empty() - idle engine test
432  * @engine: sdma engine
433  *
434  * Currently used by verbs as a latency optimization.
435  *
436  * Return:
437  * 1 - empty, 0 - non-empty
438  */
439 static inline int sdma_empty(struct sdma_engine *sde)
440 {
441 	return sde->descq_tail == sde->descq_head;
442 }
443 
444 static inline u16 sdma_descq_freecnt(struct sdma_engine *sde)
445 {
446 	return sde->descq_cnt -
447 		(sde->descq_tail -
448 		 ACCESS_ONCE(sde->descq_head)) - 1;
449 }
450 
451 static inline u16 sdma_descq_inprocess(struct sdma_engine *sde)
452 {
453 	return sde->descq_cnt - sdma_descq_freecnt(sde);
454 }
455 
456 /*
457  * Either head_lock or tail lock required to see
458  * a steady state.
459  */
460 static inline int __sdma_running(struct sdma_engine *engine)
461 {
462 	return engine->state.current_state == sdma_state_s99_running;
463 }
464 
465 /**
466  * sdma_running() - state suitability test
467  * @engine: sdma engine
468  *
469  * sdma_running probes the internal state to determine if it is suitable
470  * for submitting packets.
471  *
472  * Return:
473  * 1 - ok to submit, 0 - not ok to submit
474  *
475  */
476 static inline int sdma_running(struct sdma_engine *engine)
477 {
478 	unsigned long flags;
479 	int ret;
480 
481 	spin_lock_irqsave(&engine->tail_lock, flags);
482 	ret = __sdma_running(engine);
483 	spin_unlock_irqrestore(&engine->tail_lock, flags);
484 	return ret;
485 }
486 
487 void _sdma_txreq_ahgadd(
488 	struct sdma_txreq *tx,
489 	u8 num_ahg,
490 	u8 ahg_entry,
491 	u32 *ahg,
492 	u8 ahg_hlen);
493 
494 /**
495  * sdma_txinit_ahg() - initialize an sdma_txreq struct with AHG
496  * @tx: tx request to initialize
497  * @flags: flags to key last descriptor additions
498  * @tlen: total packet length (pbc + headers + data)
499  * @ahg_entry: ahg entry to use  (0 - 31)
500  * @num_ahg: ahg descriptor for first descriptor (0 - 9)
501  * @ahg: array of AHG descriptors (up to 9 entries)
502  * @ahg_hlen: number of bytes from ASIC entry to use
503  * @cb: callback
504  *
505  * The allocation of the sdma_txreq and it enclosing structure is user
506  * dependent.  This routine must be called to initialize the user independent
507  * fields.
508  *
509  * The currently supported flags are SDMA_TXREQ_F_URGENT,
510  * SDMA_TXREQ_F_AHG_COPY, and SDMA_TXREQ_F_USE_AHG.
511  *
512  * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
513  * completion is desired as soon as possible.
514  *
515  * SDMA_TXREQ_F_AHG_COPY causes the header in the first descriptor to be
516  * copied to chip entry. SDMA_TXREQ_F_USE_AHG causes the code to add in
517  * the AHG descriptors into the first 1 to 3 descriptors.
518  *
519  * Completions of submitted requests can be gotten on selected
520  * txreqs by giving a completion routine callback to sdma_txinit() or
521  * sdma_txinit_ahg().  The environment in which the callback runs
522  * can be from an ISR, a tasklet, or a thread, so no sleeping
523  * kernel routines can be used.   Aspects of the sdma ring may
524  * be locked so care should be taken with locking.
525  *
526  * The callback pointer can be NULL to avoid any callback for the packet
527  * being submitted. The callback will be provided this tx, a status, and a flag.
528  *
529  * The status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
530  * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
531  *
532  * The flag, if the is the iowait had been used, indicates the iowait
533  * sdma_busy count has reached zero.
534  *
535  * user data portion of tlen should be precise.   The sdma_txadd_* entrances
536  * will pad with a descriptor references 1 - 3 bytes when the number of bytes
537  * specified in tlen have been supplied to the sdma_txreq.
538  *
539  * ahg_hlen is used to determine the number of on-chip entry bytes to
540  * use as the header.   This is for cases where the stored header is
541  * larger than the header to be used in a packet.  This is typical
542  * for verbs where an RDMA_WRITE_FIRST is larger than the packet in
543  * and RDMA_WRITE_MIDDLE.
544  *
545  */
546 static inline int sdma_txinit_ahg(
547 	struct sdma_txreq *tx,
548 	u16 flags,
549 	u16 tlen,
550 	u8 ahg_entry,
551 	u8 num_ahg,
552 	u32 *ahg,
553 	u8 ahg_hlen,
554 	void (*cb)(struct sdma_txreq *, int))
555 {
556 	if (tlen == 0)
557 		return -ENODATA;
558 	if (tlen > MAX_SDMA_PKT_SIZE)
559 		return -EMSGSIZE;
560 	tx->desc_limit = ARRAY_SIZE(tx->descs);
561 	tx->descp = &tx->descs[0];
562 	INIT_LIST_HEAD(&tx->list);
563 	tx->num_desc = 0;
564 	tx->flags = flags;
565 	tx->complete = cb;
566 	tx->coalesce_buf = NULL;
567 	tx->wait = NULL;
568 	tx->packet_len = tlen;
569 	tx->tlen = tx->packet_len;
570 	tx->descs[0].qw[0] = SDMA_DESC0_FIRST_DESC_FLAG;
571 	tx->descs[0].qw[1] = 0;
572 	if (flags & SDMA_TXREQ_F_AHG_COPY)
573 		tx->descs[0].qw[1] |=
574 			(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
575 				<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
576 			(((u64)SDMA_AHG_COPY & SDMA_DESC1_HEADER_MODE_MASK)
577 				<< SDMA_DESC1_HEADER_MODE_SHIFT);
578 	else if (flags & SDMA_TXREQ_F_USE_AHG && num_ahg)
579 		_sdma_txreq_ahgadd(tx, num_ahg, ahg_entry, ahg, ahg_hlen);
580 	return 0;
581 }
582 
583 /**
584  * sdma_txinit() - initialize an sdma_txreq struct (no AHG)
585  * @tx: tx request to initialize
586  * @flags: flags to key last descriptor additions
587  * @tlen: total packet length (pbc + headers + data)
588  * @cb: callback pointer
589  *
590  * The allocation of the sdma_txreq and it enclosing structure is user
591  * dependent.  This routine must be called to initialize the user
592  * independent fields.
593  *
594  * The currently supported flags is SDMA_TXREQ_F_URGENT.
595  *
596  * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
597  * completion is desired as soon as possible.
598  *
599  * Completions of submitted requests can be gotten on selected
600  * txreqs by giving a completion routine callback to sdma_txinit() or
601  * sdma_txinit_ahg().  The environment in which the callback runs
602  * can be from an ISR, a tasklet, or a thread, so no sleeping
603  * kernel routines can be used.   The head size of the sdma ring may
604  * be locked so care should be taken with locking.
605  *
606  * The callback pointer can be NULL to avoid any callback for the packet
607  * being submitted.
608  *
609  * The callback, if non-NULL,  will be provided this tx and a status.  The
610  * status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
611  * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
612  *
613  */
614 static inline int sdma_txinit(
615 	struct sdma_txreq *tx,
616 	u16 flags,
617 	u16 tlen,
618 	void (*cb)(struct sdma_txreq *, int))
619 {
620 	return sdma_txinit_ahg(tx, flags, tlen, 0, 0, NULL, 0, cb);
621 }
622 
623 /* helpers - don't use */
624 static inline int sdma_mapping_type(struct sdma_desc *d)
625 {
626 	return (d->qw[1] & SDMA_DESC1_GENERATION_SMASK)
627 		>> SDMA_DESC1_GENERATION_SHIFT;
628 }
629 
630 static inline size_t sdma_mapping_len(struct sdma_desc *d)
631 {
632 	return (d->qw[0] & SDMA_DESC0_BYTE_COUNT_SMASK)
633 		>> SDMA_DESC0_BYTE_COUNT_SHIFT;
634 }
635 
636 static inline dma_addr_t sdma_mapping_addr(struct sdma_desc *d)
637 {
638 	return (d->qw[0] & SDMA_DESC0_PHY_ADDR_SMASK)
639 		>> SDMA_DESC0_PHY_ADDR_SHIFT;
640 }
641 
642 static inline void make_tx_sdma_desc(
643 	struct sdma_txreq *tx,
644 	int type,
645 	dma_addr_t addr,
646 	size_t len)
647 {
648 	struct sdma_desc *desc = &tx->descp[tx->num_desc];
649 
650 	if (!tx->num_desc) {
651 		/* qw[0] zero; qw[1] first, ahg mode already in from init */
652 		desc->qw[1] |= ((u64)type & SDMA_DESC1_GENERATION_MASK)
653 				<< SDMA_DESC1_GENERATION_SHIFT;
654 	} else {
655 		desc->qw[0] = 0;
656 		desc->qw[1] = ((u64)type & SDMA_DESC1_GENERATION_MASK)
657 				<< SDMA_DESC1_GENERATION_SHIFT;
658 	}
659 	desc->qw[0] |= (((u64)addr & SDMA_DESC0_PHY_ADDR_MASK)
660 				<< SDMA_DESC0_PHY_ADDR_SHIFT) |
661 			(((u64)len & SDMA_DESC0_BYTE_COUNT_MASK)
662 				<< SDMA_DESC0_BYTE_COUNT_SHIFT);
663 }
664 
665 /* helper to extend txreq */
666 int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
667 			   int type, void *kvaddr, struct page *page,
668 			   unsigned long offset, u16 len);
669 int _pad_sdma_tx_descs(struct hfi1_devdata *, struct sdma_txreq *);
670 void __sdma_txclean(struct hfi1_devdata *, struct sdma_txreq *);
671 
672 static inline void sdma_txclean(struct hfi1_devdata *dd, struct sdma_txreq *tx)
673 {
674 	if (tx->num_desc)
675 		__sdma_txclean(dd, tx);
676 }
677 
678 /* helpers used by public routines */
679 static inline void _sdma_close_tx(struct hfi1_devdata *dd,
680 				  struct sdma_txreq *tx)
681 {
682 	tx->descp[tx->num_desc].qw[0] |=
683 		SDMA_DESC0_LAST_DESC_FLAG;
684 	tx->descp[tx->num_desc].qw[1] |=
685 		dd->default_desc1;
686 	if (tx->flags & SDMA_TXREQ_F_URGENT)
687 		tx->descp[tx->num_desc].qw[1] |=
688 			(SDMA_DESC1_HEAD_TO_HOST_FLAG |
689 			 SDMA_DESC1_INT_REQ_FLAG);
690 }
691 
692 static inline int _sdma_txadd_daddr(
693 	struct hfi1_devdata *dd,
694 	int type,
695 	struct sdma_txreq *tx,
696 	dma_addr_t addr,
697 	u16 len)
698 {
699 	int rval = 0;
700 
701 	make_tx_sdma_desc(
702 		tx,
703 		type,
704 		addr, len);
705 	WARN_ON(len > tx->tlen);
706 	tx->tlen -= len;
707 	/* special cases for last */
708 	if (!tx->tlen) {
709 		if (tx->packet_len & (sizeof(u32) - 1)) {
710 			rval = _pad_sdma_tx_descs(dd, tx);
711 			if (rval)
712 				return rval;
713 		} else {
714 			_sdma_close_tx(dd, tx);
715 		}
716 	}
717 	tx->num_desc++;
718 	return rval;
719 }
720 
721 /**
722  * sdma_txadd_page() - add a page to the sdma_txreq
723  * @dd: the device to use for mapping
724  * @tx: tx request to which the page is added
725  * @page: page to map
726  * @offset: offset within the page
727  * @len: length in bytes
728  *
729  * This is used to add a page/offset/length descriptor.
730  *
731  * The mapping/unmapping of the page/offset/len is automatically handled.
732  *
733  * Return:
734  * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't
735  * extend/coalesce descriptor array
736  */
737 static inline int sdma_txadd_page(
738 	struct hfi1_devdata *dd,
739 	struct sdma_txreq *tx,
740 	struct page *page,
741 	unsigned long offset,
742 	u16 len)
743 {
744 	dma_addr_t addr;
745 	int rval;
746 
747 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
748 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_PAGE,
749 					      NULL, page, offset, len);
750 		if (rval <= 0)
751 			return rval;
752 	}
753 
754 	addr = dma_map_page(
755 		       &dd->pcidev->dev,
756 		       page,
757 		       offset,
758 		       len,
759 		       DMA_TO_DEVICE);
760 
761 	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
762 		__sdma_txclean(dd, tx);
763 		return -ENOSPC;
764 	}
765 
766 	return _sdma_txadd_daddr(
767 			dd, SDMA_MAP_PAGE, tx, addr, len);
768 }
769 
770 /**
771  * sdma_txadd_daddr() - add a dma address to the sdma_txreq
772  * @dd: the device to use for mapping
773  * @tx: sdma_txreq to which the page is added
774  * @addr: dma address mapped by caller
775  * @len: length in bytes
776  *
777  * This is used to add a descriptor for memory that is already dma mapped.
778  *
779  * In this case, there is no unmapping as part of the progress processing for
780  * this memory location.
781  *
782  * Return:
783  * 0 - success, -ENOMEM - couldn't extend descriptor array
784  */
785 
786 static inline int sdma_txadd_daddr(
787 	struct hfi1_devdata *dd,
788 	struct sdma_txreq *tx,
789 	dma_addr_t addr,
790 	u16 len)
791 {
792 	int rval;
793 
794 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
795 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_NONE,
796 					      NULL, NULL, 0, 0);
797 		if (rval <= 0)
798 			return rval;
799 	}
800 
801 	return _sdma_txadd_daddr(dd, SDMA_MAP_NONE, tx, addr, len);
802 }
803 
804 /**
805  * sdma_txadd_kvaddr() - add a kernel virtual address to sdma_txreq
806  * @dd: the device to use for mapping
807  * @tx: sdma_txreq to which the page is added
808  * @kvaddr: the kernel virtual address
809  * @len: length in bytes
810  *
811  * This is used to add a descriptor referenced by the indicated kvaddr and
812  * len.
813  *
814  * The mapping/unmapping of the kvaddr and len is automatically handled.
815  *
816  * Return:
817  * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't extend/coalesce
818  * descriptor array
819  */
820 static inline int sdma_txadd_kvaddr(
821 	struct hfi1_devdata *dd,
822 	struct sdma_txreq *tx,
823 	void *kvaddr,
824 	u16 len)
825 {
826 	dma_addr_t addr;
827 	int rval;
828 
829 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
830 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_SINGLE,
831 					      kvaddr, NULL, 0, len);
832 		if (rval <= 0)
833 			return rval;
834 	}
835 
836 	addr = dma_map_single(
837 		       &dd->pcidev->dev,
838 		       kvaddr,
839 		       len,
840 		       DMA_TO_DEVICE);
841 
842 	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
843 		__sdma_txclean(dd, tx);
844 		return -ENOSPC;
845 	}
846 
847 	return _sdma_txadd_daddr(
848 			dd, SDMA_MAP_SINGLE, tx, addr, len);
849 }
850 
851 struct iowait;
852 
853 int sdma_send_txreq(struct sdma_engine *sde,
854 		    struct iowait *wait,
855 		    struct sdma_txreq *tx);
856 int sdma_send_txlist(struct sdma_engine *sde,
857 		     struct iowait *wait,
858 		     struct list_head *tx_list,
859 		     u32 *count);
860 
861 int sdma_ahg_alloc(struct sdma_engine *sde);
862 void sdma_ahg_free(struct sdma_engine *sde, int ahg_index);
863 
864 /**
865  * sdma_build_ahg - build ahg descriptor
866  * @data
867  * @dwindex
868  * @startbit
869  * @bits
870  *
871  * Build and return a 32 bit descriptor.
872  */
873 static inline u32 sdma_build_ahg_descriptor(
874 	u16 data,
875 	u8 dwindex,
876 	u8 startbit,
877 	u8 bits)
878 {
879 	return (u32)(1UL << SDMA_AHG_UPDATE_ENABLE_SHIFT |
880 		((startbit & SDMA_AHG_FIELD_START_MASK) <<
881 		SDMA_AHG_FIELD_START_SHIFT) |
882 		((bits & SDMA_AHG_FIELD_LEN_MASK) <<
883 		SDMA_AHG_FIELD_LEN_SHIFT) |
884 		((dwindex & SDMA_AHG_INDEX_MASK) <<
885 		SDMA_AHG_INDEX_SHIFT) |
886 		((data & SDMA_AHG_VALUE_MASK) <<
887 		SDMA_AHG_VALUE_SHIFT));
888 }
889 
890 /**
891  * sdma_progress - use seq number of detect head progress
892  * @sde: sdma_engine to check
893  * @seq: base seq count
894  * @tx: txreq for which we need to check descriptor availability
895  *
896  * This is used in the appropriate spot in the sleep routine
897  * to check for potential ring progress.  This routine gets the
898  * seqcount before queuing the iowait structure for progress.
899  *
900  * If the seqcount indicates that progress needs to be checked,
901  * re-submission is detected by checking whether the descriptor
902  * queue has enough descriptor for the txreq.
903  */
904 static inline unsigned sdma_progress(struct sdma_engine *sde, unsigned seq,
905 				     struct sdma_txreq *tx)
906 {
907 	if (read_seqretry(&sde->head_lock, seq)) {
908 		sde->desc_avail = sdma_descq_freecnt(sde);
909 		if (tx->num_desc > sde->desc_avail)
910 			return 0;
911 		return 1;
912 	}
913 	return 0;
914 }
915 
916 /**
917  * sdma_iowait_schedule() - initialize wait structure
918  * @sde: sdma_engine to schedule
919  * @wait: wait struct to schedule
920  *
921  * This function initializes the iowait
922  * structure embedded in the QP or PQ.
923  *
924  */
925 static inline void sdma_iowait_schedule(
926 	struct sdma_engine *sde,
927 	struct iowait *wait)
928 {
929 	struct hfi1_pportdata *ppd = sde->dd->pport;
930 
931 	iowait_schedule(wait, ppd->hfi1_wq, sde->cpu);
932 }
933 
934 /* for use by interrupt handling */
935 void sdma_engine_error(struct sdma_engine *sde, u64 status);
936 void sdma_engine_interrupt(struct sdma_engine *sde, u64 status);
937 
938 /*
939  *
940  * The diagram below details the relationship of the mapping structures
941  *
942  * Since the mapping now allows for non-uniform engines per vl, the
943  * number of engines for a vl is either the vl_engines[vl] or
944  * a computation based on num_sdma/num_vls:
945  *
946  * For example:
947  * nactual = vl_engines ? vl_engines[vl] : num_sdma/num_vls
948  *
949  * n = roundup to next highest power of 2 using nactual
950  *
951  * In the case where there are num_sdma/num_vls doesn't divide
952  * evenly, the extras are added from the last vl downward.
953  *
954  * For the case where n > nactual, the engines are assigned
955  * in a round robin fashion wrapping back to the first engine
956  * for a particular vl.
957  *
958  *               dd->sdma_map
959  *                    |                                   sdma_map_elem[0]
960  *                    |                                +--------------------+
961  *                    v                                |       mask         |
962  *               sdma_vl_map                           |--------------------|
963  *      +--------------------------+                   | sde[0] -> eng 1    |
964  *      |    list (RCU)            |                   |--------------------|
965  *      |--------------------------|                 ->| sde[1] -> eng 2    |
966  *      |    mask                  |              --/  |--------------------|
967  *      |--------------------------|            -/     |        *           |
968  *      |    actual_vls (max 8)    |          -/       |--------------------|
969  *      |--------------------------|       --/         | sde[n-1] -> eng n  |
970  *      |    vls (max 8)           |     -/            +--------------------+
971  *      |--------------------------|  --/
972  *      |    map[0]                |-/
973  *      |--------------------------|                   +---------------------+
974  *      |    map[1]                |---                |       mask          |
975  *      |--------------------------|   \----           |---------------------|
976  *      |           *              |        \--        | sde[0] -> eng 1+n   |
977  *      |           *              |           \----   |---------------------|
978  *      |           *              |                \->| sde[1] -> eng 2+n   |
979  *      |--------------------------|                   |---------------------|
980  *      |   map[vls - 1]           |-                  |         *           |
981  *      +--------------------------+ \-                |---------------------|
982  *                                     \-              | sde[m-1] -> eng m+n |
983  *                                       \             +---------------------+
984  *                                        \-
985  *                                          \
986  *                                           \-        +----------------------+
987  *                                             \-      |       mask           |
988  *                                               \     |----------------------|
989  *                                                \-   | sde[0] -> eng 1+m+n  |
990  *                                                  \- |----------------------|
991  *                                                    >| sde[1] -> eng 2+m+n  |
992  *                                                     |----------------------|
993  *                                                     |         *            |
994  *                                                     |----------------------|
995  *                                                     | sde[o-1] -> eng o+m+n|
996  *                                                     +----------------------+
997  *
998  */
999 
1000 /**
1001  * struct sdma_map_elem - mapping for a vl
1002  * @mask - selector mask
1003  * @sde - array of engines for this vl
1004  *
1005  * The mask is used to "mod" the selector
1006  * to produce index into the trailing
1007  * array of sdes.
1008  */
1009 struct sdma_map_elem {
1010 	u32 mask;
1011 	struct sdma_engine *sde[0];
1012 };
1013 
1014 /**
1015  * struct sdma_map_el - mapping for a vl
1016  * @engine_to_vl - map of an engine to a vl
1017  * @list - rcu head for free callback
1018  * @mask - vl mask to "mod" the vl to produce an index to map array
1019  * @actual_vls - number of vls
1020  * @vls - number of vls rounded to next power of 2
1021  * @map - array of sdma_map_elem entries
1022  *
1023  * This is the parent mapping structure.  The trailing
1024  * members of the struct point to sdma_map_elem entries, which
1025  * in turn point to an array of sde's for that vl.
1026  */
1027 struct sdma_vl_map {
1028 	s8 engine_to_vl[TXE_NUM_SDMA_ENGINES];
1029 	struct rcu_head list;
1030 	u32 mask;
1031 	u8 actual_vls;
1032 	u8 vls;
1033 	struct sdma_map_elem *map[0];
1034 };
1035 
1036 int sdma_map_init(
1037 	struct hfi1_devdata *dd,
1038 	u8 port,
1039 	u8 num_vls,
1040 	u8 *vl_engines);
1041 
1042 /* slow path */
1043 void _sdma_engine_progress_schedule(struct sdma_engine *sde);
1044 
1045 /**
1046  * sdma_engine_progress_schedule() - schedule progress on engine
1047  * @sde: sdma_engine to schedule progress
1048  *
1049  * This is the fast path.
1050  *
1051  */
1052 static inline void sdma_engine_progress_schedule(
1053 	struct sdma_engine *sde)
1054 {
1055 	if (!sde || sdma_descq_inprocess(sde) < (sde->descq_cnt / 8))
1056 		return;
1057 	_sdma_engine_progress_schedule(sde);
1058 }
1059 
1060 struct sdma_engine *sdma_select_engine_sc(
1061 	struct hfi1_devdata *dd,
1062 	u32 selector,
1063 	u8 sc5);
1064 
1065 struct sdma_engine *sdma_select_engine_vl(
1066 	struct hfi1_devdata *dd,
1067 	u32 selector,
1068 	u8 vl);
1069 
1070 struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd,
1071 					    u32 selector, u8 vl);
1072 ssize_t sdma_get_cpu_to_sde_map(struct sdma_engine *sde, char *buf);
1073 ssize_t sdma_set_cpu_to_sde_map(struct sdma_engine *sde, const char *buf,
1074 				size_t count);
1075 int sdma_engine_get_vl(struct sdma_engine *sde);
1076 void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *);
1077 void sdma_seqfile_dump_cpu_list(struct seq_file *s, struct hfi1_devdata *dd,
1078 				unsigned long cpuid);
1079 
1080 #ifdef CONFIG_SDMA_VERBOSITY
1081 void sdma_dumpstate(struct sdma_engine *);
1082 #endif
1083 static inline char *slashstrip(char *s)
1084 {
1085 	char *r = s;
1086 
1087 	while (*s)
1088 		if (*s++ == '/')
1089 			r = s;
1090 	return r;
1091 }
1092 
1093 u16 sdma_get_descq_cnt(void);
1094 
1095 extern uint mod_num_sdma;
1096 
1097 void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid);
1098 
1099 #endif
1100