xref: /openbmc/linux/drivers/infiniband/hw/hfi1/sdma.h (revision 5d862ec6)
1 /* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
2 /*
3  * Copyright(c) 2015 - 2018 Intel Corporation.
4  */
5 
6 #ifndef _HFI1_SDMA_H
7 #define _HFI1_SDMA_H
8 
9 #include <linux/types.h>
10 #include <linux/list.h>
11 #include <asm/byteorder.h>
12 #include <linux/workqueue.h>
13 #include <linux/rculist.h>
14 
15 #include "hfi.h"
16 #include "verbs.h"
17 #include "sdma_txreq.h"
18 
19 /* Hardware limit */
20 #define MAX_DESC 64
21 /* Hardware limit for SDMA packet size */
22 #define MAX_SDMA_PKT_SIZE ((16 * 1024) - 1)
23 
24 #define SDMA_MAP_NONE          0
25 #define SDMA_MAP_SINGLE        1
26 #define SDMA_MAP_PAGE          2
27 
28 #define SDMA_AHG_VALUE_MASK          0xffff
29 #define SDMA_AHG_VALUE_SHIFT         0
30 #define SDMA_AHG_INDEX_MASK          0xf
31 #define SDMA_AHG_INDEX_SHIFT         16
32 #define SDMA_AHG_FIELD_LEN_MASK      0xf
33 #define SDMA_AHG_FIELD_LEN_SHIFT     20
34 #define SDMA_AHG_FIELD_START_MASK    0x1f
35 #define SDMA_AHG_FIELD_START_SHIFT   24
36 #define SDMA_AHG_UPDATE_ENABLE_MASK  0x1
37 #define SDMA_AHG_UPDATE_ENABLE_SHIFT 31
38 
39 /* AHG modes */
40 
41 /*
42  * Be aware the ordering and values
43  * for SDMA_AHG_APPLY_UPDATE[123]
44  * are assumed in generating a skip
45  * count in submit_tx() in sdma.c
46  */
47 #define SDMA_AHG_NO_AHG              0
48 #define SDMA_AHG_COPY                1
49 #define SDMA_AHG_APPLY_UPDATE1       2
50 #define SDMA_AHG_APPLY_UPDATE2       3
51 #define SDMA_AHG_APPLY_UPDATE3       4
52 
53 /*
54  * Bits defined in the send DMA descriptor.
55  */
56 #define SDMA_DESC0_FIRST_DESC_FLAG      BIT_ULL(63)
57 #define SDMA_DESC0_LAST_DESC_FLAG       BIT_ULL(62)
58 #define SDMA_DESC0_BYTE_COUNT_SHIFT     48
59 #define SDMA_DESC0_BYTE_COUNT_WIDTH     14
60 #define SDMA_DESC0_BYTE_COUNT_MASK \
61 	((1ULL << SDMA_DESC0_BYTE_COUNT_WIDTH) - 1)
62 #define SDMA_DESC0_BYTE_COUNT_SMASK \
63 	(SDMA_DESC0_BYTE_COUNT_MASK << SDMA_DESC0_BYTE_COUNT_SHIFT)
64 #define SDMA_DESC0_PHY_ADDR_SHIFT       0
65 #define SDMA_DESC0_PHY_ADDR_WIDTH       48
66 #define SDMA_DESC0_PHY_ADDR_MASK \
67 	((1ULL << SDMA_DESC0_PHY_ADDR_WIDTH) - 1)
68 #define SDMA_DESC0_PHY_ADDR_SMASK \
69 	(SDMA_DESC0_PHY_ADDR_MASK << SDMA_DESC0_PHY_ADDR_SHIFT)
70 
71 #define SDMA_DESC1_HEADER_UPDATE1_SHIFT 32
72 #define SDMA_DESC1_HEADER_UPDATE1_WIDTH 32
73 #define SDMA_DESC1_HEADER_UPDATE1_MASK \
74 	((1ULL << SDMA_DESC1_HEADER_UPDATE1_WIDTH) - 1)
75 #define SDMA_DESC1_HEADER_UPDATE1_SMASK \
76 	(SDMA_DESC1_HEADER_UPDATE1_MASK << SDMA_DESC1_HEADER_UPDATE1_SHIFT)
77 #define SDMA_DESC1_HEADER_MODE_SHIFT    13
78 #define SDMA_DESC1_HEADER_MODE_WIDTH    3
79 #define SDMA_DESC1_HEADER_MODE_MASK \
80 	((1ULL << SDMA_DESC1_HEADER_MODE_WIDTH) - 1)
81 #define SDMA_DESC1_HEADER_MODE_SMASK \
82 	(SDMA_DESC1_HEADER_MODE_MASK << SDMA_DESC1_HEADER_MODE_SHIFT)
83 #define SDMA_DESC1_HEADER_INDEX_SHIFT   8
84 #define SDMA_DESC1_HEADER_INDEX_WIDTH   5
85 #define SDMA_DESC1_HEADER_INDEX_MASK \
86 	((1ULL << SDMA_DESC1_HEADER_INDEX_WIDTH) - 1)
87 #define SDMA_DESC1_HEADER_INDEX_SMASK \
88 	(SDMA_DESC1_HEADER_INDEX_MASK << SDMA_DESC1_HEADER_INDEX_SHIFT)
89 #define SDMA_DESC1_HEADER_DWS_SHIFT     4
90 #define SDMA_DESC1_HEADER_DWS_WIDTH     4
91 #define SDMA_DESC1_HEADER_DWS_MASK \
92 	((1ULL << SDMA_DESC1_HEADER_DWS_WIDTH) - 1)
93 #define SDMA_DESC1_HEADER_DWS_SMASK \
94 	(SDMA_DESC1_HEADER_DWS_MASK << SDMA_DESC1_HEADER_DWS_SHIFT)
95 #define SDMA_DESC1_GENERATION_SHIFT     2
96 #define SDMA_DESC1_GENERATION_WIDTH     2
97 #define SDMA_DESC1_GENERATION_MASK \
98 	((1ULL << SDMA_DESC1_GENERATION_WIDTH) - 1)
99 #define SDMA_DESC1_GENERATION_SMASK \
100 	(SDMA_DESC1_GENERATION_MASK << SDMA_DESC1_GENERATION_SHIFT)
101 #define SDMA_DESC1_INT_REQ_FLAG         BIT_ULL(1)
102 #define SDMA_DESC1_HEAD_TO_HOST_FLAG    BIT_ULL(0)
103 
104 enum sdma_states {
105 	sdma_state_s00_hw_down,
106 	sdma_state_s10_hw_start_up_halt_wait,
107 	sdma_state_s15_hw_start_up_clean_wait,
108 	sdma_state_s20_idle,
109 	sdma_state_s30_sw_clean_up_wait,
110 	sdma_state_s40_hw_clean_up_wait,
111 	sdma_state_s50_hw_halt_wait,
112 	sdma_state_s60_idle_halt_wait,
113 	sdma_state_s80_hw_freeze,
114 	sdma_state_s82_freeze_sw_clean,
115 	sdma_state_s99_running,
116 };
117 
118 enum sdma_events {
119 	sdma_event_e00_go_hw_down,
120 	sdma_event_e10_go_hw_start,
121 	sdma_event_e15_hw_halt_done,
122 	sdma_event_e25_hw_clean_up_done,
123 	sdma_event_e30_go_running,
124 	sdma_event_e40_sw_cleaned,
125 	sdma_event_e50_hw_cleaned,
126 	sdma_event_e60_hw_halted,
127 	sdma_event_e70_go_idle,
128 	sdma_event_e80_hw_freeze,
129 	sdma_event_e81_hw_frozen,
130 	sdma_event_e82_hw_unfreeze,
131 	sdma_event_e85_link_down,
132 	sdma_event_e90_sw_halted,
133 };
134 
135 struct sdma_set_state_action {
136 	unsigned op_enable:1;
137 	unsigned op_intenable:1;
138 	unsigned op_halt:1;
139 	unsigned op_cleanup:1;
140 	unsigned go_s99_running_tofalse:1;
141 	unsigned go_s99_running_totrue:1;
142 };
143 
144 struct sdma_state {
145 	struct kref          kref;
146 	struct completion    comp;
147 	enum sdma_states current_state;
148 	unsigned             current_op;
149 	unsigned             go_s99_running;
150 	/* debugging/development */
151 	enum sdma_states previous_state;
152 	unsigned             previous_op;
153 	enum sdma_events last_event;
154 };
155 
156 /**
157  * DOC: sdma exported routines
158  *
159  * These sdma routines fit into three categories:
160  * - The SDMA API for building and submitting packets
161  *   to the ring
162  *
163  * - Initialization and tear down routines to buildup
164  *   and tear down SDMA
165  *
166  * - ISR entrances to handle interrupts, state changes
167  *   and errors
168  */
169 
170 /**
171  * DOC: sdma PSM/verbs API
172  *
173  * The sdma API is designed to be used by both PSM
174  * and verbs to supply packets to the SDMA ring.
175  *
176  * The usage of the API is as follows:
177  *
178  * Embed a struct iowait in the QP or
179  * PQ.  The iowait should be initialized with a
180  * call to iowait_init().
181  *
182  * The user of the API should create an allocation method
183  * for their version of the txreq. slabs, pre-allocated lists,
184  * and dma pools can be used.  Once the user's overload of
185  * the sdma_txreq has been allocated, the sdma_txreq member
186  * must be initialized with sdma_txinit() or sdma_txinit_ahg().
187  *
188  * The txreq must be declared with the sdma_txreq first.
189  *
190  * The tx request, once initialized,  is manipulated with calls to
191  * sdma_txadd_daddr(), sdma_txadd_page(), or sdma_txadd_kvaddr()
192  * for each disjoint memory location.  It is the user's responsibility
193  * to understand the packet boundaries and page boundaries to do the
194  * appropriate number of sdma_txadd_* calls..  The user
195  * must be prepared to deal with failures from these routines due to
196  * either memory allocation or dma_mapping failures.
197  *
198  * The mapping specifics for each memory location are recorded
199  * in the tx. Memory locations added with sdma_txadd_page()
200  * and sdma_txadd_kvaddr() are automatically mapped when added
201  * to the tx and nmapped as part of the progress processing in the
202  * SDMA interrupt handling.
203  *
204  * sdma_txadd_daddr() is used to add an dma_addr_t memory to the
205  * tx.   An example of a use case would be a pre-allocated
206  * set of headers allocated via dma_pool_alloc() or
207  * dma_alloc_coherent().  For these memory locations, it
208  * is the responsibility of the user to handle that unmapping.
209  * (This would usually be at an unload or job termination.)
210  *
211  * The routine sdma_send_txreq() is used to submit
212  * a tx to the ring after the appropriate number of
213  * sdma_txadd_* have been done.
214  *
215  * If it is desired to send a burst of sdma_txreqs, sdma_send_txlist()
216  * can be used to submit a list of packets.
217  *
218  * The user is free to use the link overhead in the struct sdma_txreq as
219  * long as the tx isn't in flight.
220  *
221  * The extreme degenerate case of the number of descriptors
222  * exceeding the ring size is automatically handled as
223  * memory locations are added.  An overflow of the descriptor
224  * array that is part of the sdma_txreq is also automatically
225  * handled.
226  *
227  */
228 
229 /**
230  * DOC: Infrastructure calls
231  *
232  * sdma_init() is used to initialize data structures and
233  * CSRs for the desired number of SDMA engines.
234  *
235  * sdma_start() is used to kick the SDMA engines initialized
236  * with sdma_init().   Interrupts must be enabled at this
237  * point since aspects of the state machine are interrupt
238  * driven.
239  *
240  * sdma_engine_error() and sdma_engine_interrupt() are
241  * entrances for interrupts.
242  *
243  * sdma_map_init() is for the management of the mapping
244  * table when the number of vls is changed.
245  *
246  */
247 
248 /*
249  * struct hw_sdma_desc - raw 128 bit SDMA descriptor
250  *
251  * This is the raw descriptor in the SDMA ring
252  */
253 struct hw_sdma_desc {
254 	/* private:  don't use directly */
255 	__le64 qw[2];
256 };
257 
258 /**
259  * struct sdma_engine - Data pertaining to each SDMA engine.
260  * @dd: a back-pointer to the device data
261  * @ppd: per port back-pointer
262  * @imask: mask for irq manipulation
263  * @idle_mask: mask for determining if an interrupt is due to sdma_idle
264  *
265  * This structure has the state for each sdma_engine.
266  *
267  * Accessing to non public fields are not supported
268  * since the private members are subject to change.
269  */
270 struct sdma_engine {
271 	/* read mostly */
272 	struct hfi1_devdata *dd;
273 	struct hfi1_pportdata *ppd;
274 	/* private: */
275 	void __iomem *tail_csr;
276 	u64 imask;			/* clear interrupt mask */
277 	u64 idle_mask;
278 	u64 progress_mask;
279 	u64 int_mask;
280 	/* private: */
281 	volatile __le64      *head_dma; /* DMA'ed by chip */
282 	/* private: */
283 	dma_addr_t            head_phys;
284 	/* private: */
285 	struct hw_sdma_desc *descq;
286 	/* private: */
287 	unsigned descq_full_count;
288 	struct sdma_txreq **tx_ring;
289 	/* private: */
290 	dma_addr_t            descq_phys;
291 	/* private */
292 	u32 sdma_mask;
293 	/* private */
294 	struct sdma_state state;
295 	/* private */
296 	int cpu;
297 	/* private: */
298 	u8 sdma_shift;
299 	/* private: */
300 	u8 this_idx; /* zero relative engine */
301 	/* protect changes to senddmactrl shadow */
302 	spinlock_t senddmactrl_lock;
303 	/* private: */
304 	u64 p_senddmactrl;		/* shadow per-engine SendDmaCtrl */
305 
306 	/* read/write using tail_lock */
307 	spinlock_t            tail_lock ____cacheline_aligned_in_smp;
308 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
309 	/* private: */
310 	u64                   tail_sn;
311 #endif
312 	/* private: */
313 	u32                   descq_tail;
314 	/* private: */
315 	unsigned long         ahg_bits;
316 	/* private: */
317 	u16                   desc_avail;
318 	/* private: */
319 	u16                   tx_tail;
320 	/* private: */
321 	u16 descq_cnt;
322 
323 	/* read/write using head_lock */
324 	/* private: */
325 	seqlock_t            head_lock ____cacheline_aligned_in_smp;
326 #ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
327 	/* private: */
328 	u64                   head_sn;
329 #endif
330 	/* private: */
331 	u32                   descq_head;
332 	/* private: */
333 	u16                   tx_head;
334 	/* private: */
335 	u64                   last_status;
336 	/* private */
337 	u64                     err_cnt;
338 	/* private */
339 	u64                     sdma_int_cnt;
340 	u64                     idle_int_cnt;
341 	u64                     progress_int_cnt;
342 
343 	/* private: */
344 	seqlock_t            waitlock;
345 	struct list_head      dmawait;
346 
347 	/* CONFIG SDMA for now, just blindly duplicate */
348 	/* private: */
349 	struct tasklet_struct sdma_hw_clean_up_task
350 		____cacheline_aligned_in_smp;
351 
352 	/* private: */
353 	struct tasklet_struct sdma_sw_clean_up_task
354 		____cacheline_aligned_in_smp;
355 	/* private: */
356 	struct work_struct err_halt_worker;
357 	/* private */
358 	struct timer_list     err_progress_check_timer;
359 	u32                   progress_check_head;
360 	/* private: */
361 	struct work_struct flush_worker;
362 	/* protect flush list */
363 	spinlock_t flushlist_lock;
364 	/* private: */
365 	struct list_head flushlist;
366 	struct cpumask cpu_mask;
367 	struct kobject kobj;
368 	u32 msix_intr;
369 };
370 
371 int sdma_init(struct hfi1_devdata *dd, u8 port);
372 void sdma_start(struct hfi1_devdata *dd);
373 void sdma_exit(struct hfi1_devdata *dd);
374 void sdma_clean(struct hfi1_devdata *dd, size_t num_engines);
375 void sdma_all_running(struct hfi1_devdata *dd);
376 void sdma_all_idle(struct hfi1_devdata *dd);
377 void sdma_freeze_notify(struct hfi1_devdata *dd, int go_idle);
378 void sdma_freeze(struct hfi1_devdata *dd);
379 void sdma_unfreeze(struct hfi1_devdata *dd);
380 void sdma_wait(struct hfi1_devdata *dd);
381 
382 /**
383  * sdma_empty() - idle engine test
384  * @engine: sdma engine
385  *
386  * Currently used by verbs as a latency optimization.
387  *
388  * Return:
389  * 1 - empty, 0 - non-empty
390  */
391 static inline int sdma_empty(struct sdma_engine *sde)
392 {
393 	return sde->descq_tail == sde->descq_head;
394 }
395 
396 static inline u16 sdma_descq_freecnt(struct sdma_engine *sde)
397 {
398 	return sde->descq_cnt -
399 		(sde->descq_tail -
400 		 READ_ONCE(sde->descq_head)) - 1;
401 }
402 
403 static inline u16 sdma_descq_inprocess(struct sdma_engine *sde)
404 {
405 	return sde->descq_cnt - sdma_descq_freecnt(sde);
406 }
407 
408 /*
409  * Either head_lock or tail lock required to see
410  * a steady state.
411  */
412 static inline int __sdma_running(struct sdma_engine *engine)
413 {
414 	return engine->state.current_state == sdma_state_s99_running;
415 }
416 
417 /**
418  * sdma_running() - state suitability test
419  * @engine: sdma engine
420  *
421  * sdma_running probes the internal state to determine if it is suitable
422  * for submitting packets.
423  *
424  * Return:
425  * 1 - ok to submit, 0 - not ok to submit
426  *
427  */
428 static inline int sdma_running(struct sdma_engine *engine)
429 {
430 	unsigned long flags;
431 	int ret;
432 
433 	spin_lock_irqsave(&engine->tail_lock, flags);
434 	ret = __sdma_running(engine);
435 	spin_unlock_irqrestore(&engine->tail_lock, flags);
436 	return ret;
437 }
438 
439 void _sdma_txreq_ahgadd(
440 	struct sdma_txreq *tx,
441 	u8 num_ahg,
442 	u8 ahg_entry,
443 	u32 *ahg,
444 	u8 ahg_hlen);
445 
446 /**
447  * sdma_txinit_ahg() - initialize an sdma_txreq struct with AHG
448  * @tx: tx request to initialize
449  * @flags: flags to key last descriptor additions
450  * @tlen: total packet length (pbc + headers + data)
451  * @ahg_entry: ahg entry to use  (0 - 31)
452  * @num_ahg: ahg descriptor for first descriptor (0 - 9)
453  * @ahg: array of AHG descriptors (up to 9 entries)
454  * @ahg_hlen: number of bytes from ASIC entry to use
455  * @cb: callback
456  *
457  * The allocation of the sdma_txreq and it enclosing structure is user
458  * dependent.  This routine must be called to initialize the user independent
459  * fields.
460  *
461  * The currently supported flags are SDMA_TXREQ_F_URGENT,
462  * SDMA_TXREQ_F_AHG_COPY, and SDMA_TXREQ_F_USE_AHG.
463  *
464  * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
465  * completion is desired as soon as possible.
466  *
467  * SDMA_TXREQ_F_AHG_COPY causes the header in the first descriptor to be
468  * copied to chip entry. SDMA_TXREQ_F_USE_AHG causes the code to add in
469  * the AHG descriptors into the first 1 to 3 descriptors.
470  *
471  * Completions of submitted requests can be gotten on selected
472  * txreqs by giving a completion routine callback to sdma_txinit() or
473  * sdma_txinit_ahg().  The environment in which the callback runs
474  * can be from an ISR, a tasklet, or a thread, so no sleeping
475  * kernel routines can be used.   Aspects of the sdma ring may
476  * be locked so care should be taken with locking.
477  *
478  * The callback pointer can be NULL to avoid any callback for the packet
479  * being submitted. The callback will be provided this tx, a status, and a flag.
480  *
481  * The status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
482  * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
483  *
484  * The flag, if the is the iowait had been used, indicates the iowait
485  * sdma_busy count has reached zero.
486  *
487  * user data portion of tlen should be precise.   The sdma_txadd_* entrances
488  * will pad with a descriptor references 1 - 3 bytes when the number of bytes
489  * specified in tlen have been supplied to the sdma_txreq.
490  *
491  * ahg_hlen is used to determine the number of on-chip entry bytes to
492  * use as the header.   This is for cases where the stored header is
493  * larger than the header to be used in a packet.  This is typical
494  * for verbs where an RDMA_WRITE_FIRST is larger than the packet in
495  * and RDMA_WRITE_MIDDLE.
496  *
497  */
498 static inline int sdma_txinit_ahg(
499 	struct sdma_txreq *tx,
500 	u16 flags,
501 	u16 tlen,
502 	u8 ahg_entry,
503 	u8 num_ahg,
504 	u32 *ahg,
505 	u8 ahg_hlen,
506 	void (*cb)(struct sdma_txreq *, int))
507 {
508 	if (tlen == 0)
509 		return -ENODATA;
510 	if (tlen > MAX_SDMA_PKT_SIZE)
511 		return -EMSGSIZE;
512 	tx->desc_limit = ARRAY_SIZE(tx->descs);
513 	tx->descp = &tx->descs[0];
514 	INIT_LIST_HEAD(&tx->list);
515 	tx->num_desc = 0;
516 	tx->flags = flags;
517 	tx->complete = cb;
518 	tx->coalesce_buf = NULL;
519 	tx->wait = NULL;
520 	tx->packet_len = tlen;
521 	tx->tlen = tx->packet_len;
522 	tx->descs[0].qw[0] = SDMA_DESC0_FIRST_DESC_FLAG;
523 	tx->descs[0].qw[1] = 0;
524 	if (flags & SDMA_TXREQ_F_AHG_COPY)
525 		tx->descs[0].qw[1] |=
526 			(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
527 				<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
528 			(((u64)SDMA_AHG_COPY & SDMA_DESC1_HEADER_MODE_MASK)
529 				<< SDMA_DESC1_HEADER_MODE_SHIFT);
530 	else if (flags & SDMA_TXREQ_F_USE_AHG && num_ahg)
531 		_sdma_txreq_ahgadd(tx, num_ahg, ahg_entry, ahg, ahg_hlen);
532 	return 0;
533 }
534 
535 /**
536  * sdma_txinit() - initialize an sdma_txreq struct (no AHG)
537  * @tx: tx request to initialize
538  * @flags: flags to key last descriptor additions
539  * @tlen: total packet length (pbc + headers + data)
540  * @cb: callback pointer
541  *
542  * The allocation of the sdma_txreq and it enclosing structure is user
543  * dependent.  This routine must be called to initialize the user
544  * independent fields.
545  *
546  * The currently supported flags is SDMA_TXREQ_F_URGENT.
547  *
548  * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
549  * completion is desired as soon as possible.
550  *
551  * Completions of submitted requests can be gotten on selected
552  * txreqs by giving a completion routine callback to sdma_txinit() or
553  * sdma_txinit_ahg().  The environment in which the callback runs
554  * can be from an ISR, a tasklet, or a thread, so no sleeping
555  * kernel routines can be used.   The head size of the sdma ring may
556  * be locked so care should be taken with locking.
557  *
558  * The callback pointer can be NULL to avoid any callback for the packet
559  * being submitted.
560  *
561  * The callback, if non-NULL,  will be provided this tx and a status.  The
562  * status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
563  * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
564  *
565  */
566 static inline int sdma_txinit(
567 	struct sdma_txreq *tx,
568 	u16 flags,
569 	u16 tlen,
570 	void (*cb)(struct sdma_txreq *, int))
571 {
572 	return sdma_txinit_ahg(tx, flags, tlen, 0, 0, NULL, 0, cb);
573 }
574 
575 /* helpers - don't use */
576 static inline int sdma_mapping_type(struct sdma_desc *d)
577 {
578 	return (d->qw[1] & SDMA_DESC1_GENERATION_SMASK)
579 		>> SDMA_DESC1_GENERATION_SHIFT;
580 }
581 
582 static inline size_t sdma_mapping_len(struct sdma_desc *d)
583 {
584 	return (d->qw[0] & SDMA_DESC0_BYTE_COUNT_SMASK)
585 		>> SDMA_DESC0_BYTE_COUNT_SHIFT;
586 }
587 
588 static inline dma_addr_t sdma_mapping_addr(struct sdma_desc *d)
589 {
590 	return (d->qw[0] & SDMA_DESC0_PHY_ADDR_SMASK)
591 		>> SDMA_DESC0_PHY_ADDR_SHIFT;
592 }
593 
594 static inline void make_tx_sdma_desc(
595 	struct sdma_txreq *tx,
596 	int type,
597 	void *pinning_ctx,
598 	dma_addr_t addr,
599 	size_t len)
600 {
601 	struct sdma_desc *desc = &tx->descp[tx->num_desc];
602 
603 	if (!tx->num_desc) {
604 		/* qw[0] zero; qw[1] first, ahg mode already in from init */
605 		desc->qw[1] |= ((u64)type & SDMA_DESC1_GENERATION_MASK)
606 				<< SDMA_DESC1_GENERATION_SHIFT;
607 	} else {
608 		desc->qw[0] = 0;
609 		desc->qw[1] = ((u64)type & SDMA_DESC1_GENERATION_MASK)
610 				<< SDMA_DESC1_GENERATION_SHIFT;
611 	}
612 	desc->qw[0] |= (((u64)addr & SDMA_DESC0_PHY_ADDR_MASK)
613 				<< SDMA_DESC0_PHY_ADDR_SHIFT) |
614 			(((u64)len & SDMA_DESC0_BYTE_COUNT_MASK)
615 				<< SDMA_DESC0_BYTE_COUNT_SHIFT);
616 	desc->pinning_ctx = pinning_ctx;
617 }
618 
619 /* helper to extend txreq */
620 int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
621 			   int type, void *kvaddr, struct page *page,
622 			   unsigned long offset, u16 len);
623 int _pad_sdma_tx_descs(struct hfi1_devdata *, struct sdma_txreq *);
624 void __sdma_txclean(struct hfi1_devdata *, struct sdma_txreq *);
625 
626 static inline void sdma_txclean(struct hfi1_devdata *dd, struct sdma_txreq *tx)
627 {
628 	if (tx->num_desc)
629 		__sdma_txclean(dd, tx);
630 }
631 
632 /* helpers used by public routines */
633 static inline void _sdma_close_tx(struct hfi1_devdata *dd,
634 				  struct sdma_txreq *tx)
635 {
636 	u16 last_desc = tx->num_desc - 1;
637 
638 	tx->descp[last_desc].qw[0] |= SDMA_DESC0_LAST_DESC_FLAG;
639 	tx->descp[last_desc].qw[1] |= dd->default_desc1;
640 	if (tx->flags & SDMA_TXREQ_F_URGENT)
641 		tx->descp[last_desc].qw[1] |= (SDMA_DESC1_HEAD_TO_HOST_FLAG |
642 					       SDMA_DESC1_INT_REQ_FLAG);
643 }
644 
645 static inline int _sdma_txadd_daddr(
646 	struct hfi1_devdata *dd,
647 	int type,
648 	void *pinning_ctx,
649 	struct sdma_txreq *tx,
650 	dma_addr_t addr,
651 	u16 len)
652 {
653 	int rval = 0;
654 
655 	make_tx_sdma_desc(
656 		tx,
657 		type,
658 		pinning_ctx,
659 		addr, len);
660 	WARN_ON(len > tx->tlen);
661 	tx->num_desc++;
662 	tx->tlen -= len;
663 	/* special cases for last */
664 	if (!tx->tlen) {
665 		if (tx->packet_len & (sizeof(u32) - 1)) {
666 			rval = _pad_sdma_tx_descs(dd, tx);
667 			if (rval)
668 				return rval;
669 		} else {
670 			_sdma_close_tx(dd, tx);
671 		}
672 	}
673 	return rval;
674 }
675 
676 /**
677  * sdma_txadd_page() - add a page to the sdma_txreq
678  * @dd: the device to use for mapping
679  * @pinning_ctx: context to be released at descriptor retirement
680  * @tx: tx request to which the page is added
681  * @page: page to map
682  * @offset: offset within the page
683  * @len: length in bytes
684  *
685  * This is used to add a page/offset/length descriptor.
686  *
687  * The mapping/unmapping of the page/offset/len is automatically handled.
688  *
689  * Return:
690  * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't
691  * extend/coalesce descriptor array
692  */
693 static inline int sdma_txadd_page(
694 	struct hfi1_devdata *dd,
695 	void *pinning_ctx,
696 	struct sdma_txreq *tx,
697 	struct page *page,
698 	unsigned long offset,
699 	u16 len)
700 {
701 	dma_addr_t addr;
702 	int rval;
703 
704 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
705 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_PAGE,
706 					      NULL, page, offset, len);
707 		if (rval <= 0)
708 			return rval;
709 	}
710 
711 	addr = dma_map_page(
712 		       &dd->pcidev->dev,
713 		       page,
714 		       offset,
715 		       len,
716 		       DMA_TO_DEVICE);
717 
718 	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
719 		__sdma_txclean(dd, tx);
720 		return -ENOSPC;
721 	}
722 
723 	return _sdma_txadd_daddr(dd, SDMA_MAP_PAGE, pinning_ctx, tx, addr, len);
724 }
725 
726 /**
727  * sdma_txadd_daddr() - add a dma address to the sdma_txreq
728  * @dd: the device to use for mapping
729  * @tx: sdma_txreq to which the page is added
730  * @addr: dma address mapped by caller
731  * @len: length in bytes
732  *
733  * This is used to add a descriptor for memory that is already dma mapped.
734  *
735  * In this case, there is no unmapping as part of the progress processing for
736  * this memory location.
737  *
738  * Return:
739  * 0 - success, -ENOMEM - couldn't extend descriptor array
740  */
741 
742 static inline int sdma_txadd_daddr(
743 	struct hfi1_devdata *dd,
744 	struct sdma_txreq *tx,
745 	dma_addr_t addr,
746 	u16 len)
747 {
748 	int rval;
749 
750 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
751 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_NONE,
752 					      NULL, NULL, 0, 0);
753 		if (rval <= 0)
754 			return rval;
755 	}
756 
757 	return _sdma_txadd_daddr(dd, SDMA_MAP_NONE, NULL, tx,
758 				 addr, len);
759 }
760 
761 /**
762  * sdma_txadd_kvaddr() - add a kernel virtual address to sdma_txreq
763  * @dd: the device to use for mapping
764  * @tx: sdma_txreq to which the page is added
765  * @kvaddr: the kernel virtual address
766  * @len: length in bytes
767  *
768  * This is used to add a descriptor referenced by the indicated kvaddr and
769  * len.
770  *
771  * The mapping/unmapping of the kvaddr and len is automatically handled.
772  *
773  * Return:
774  * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't extend/coalesce
775  * descriptor array
776  */
777 static inline int sdma_txadd_kvaddr(
778 	struct hfi1_devdata *dd,
779 	struct sdma_txreq *tx,
780 	void *kvaddr,
781 	u16 len)
782 {
783 	dma_addr_t addr;
784 	int rval;
785 
786 	if ((unlikely(tx->num_desc == tx->desc_limit))) {
787 		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_SINGLE,
788 					      kvaddr, NULL, 0, len);
789 		if (rval <= 0)
790 			return rval;
791 	}
792 
793 	addr = dma_map_single(
794 		       &dd->pcidev->dev,
795 		       kvaddr,
796 		       len,
797 		       DMA_TO_DEVICE);
798 
799 	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
800 		__sdma_txclean(dd, tx);
801 		return -ENOSPC;
802 	}
803 
804 	return _sdma_txadd_daddr(dd, SDMA_MAP_SINGLE, NULL, tx, addr, len);
805 }
806 
807 struct iowait_work;
808 
809 int sdma_send_txreq(struct sdma_engine *sde,
810 		    struct iowait_work *wait,
811 		    struct sdma_txreq *tx,
812 		    bool pkts_sent);
813 int sdma_send_txlist(struct sdma_engine *sde,
814 		     struct iowait_work *wait,
815 		     struct list_head *tx_list,
816 		     u16 *count_out);
817 
818 int sdma_ahg_alloc(struct sdma_engine *sde);
819 void sdma_ahg_free(struct sdma_engine *sde, int ahg_index);
820 
821 /**
822  * sdma_build_ahg - build ahg descriptor
823  * @data
824  * @dwindex
825  * @startbit
826  * @bits
827  *
828  * Build and return a 32 bit descriptor.
829  */
830 static inline u32 sdma_build_ahg_descriptor(
831 	u16 data,
832 	u8 dwindex,
833 	u8 startbit,
834 	u8 bits)
835 {
836 	return (u32)(1UL << SDMA_AHG_UPDATE_ENABLE_SHIFT |
837 		((startbit & SDMA_AHG_FIELD_START_MASK) <<
838 		SDMA_AHG_FIELD_START_SHIFT) |
839 		((bits & SDMA_AHG_FIELD_LEN_MASK) <<
840 		SDMA_AHG_FIELD_LEN_SHIFT) |
841 		((dwindex & SDMA_AHG_INDEX_MASK) <<
842 		SDMA_AHG_INDEX_SHIFT) |
843 		((data & SDMA_AHG_VALUE_MASK) <<
844 		SDMA_AHG_VALUE_SHIFT));
845 }
846 
847 /**
848  * sdma_progress - use seq number of detect head progress
849  * @sde: sdma_engine to check
850  * @seq: base seq count
851  * @tx: txreq for which we need to check descriptor availability
852  *
853  * This is used in the appropriate spot in the sleep routine
854  * to check for potential ring progress.  This routine gets the
855  * seqcount before queuing the iowait structure for progress.
856  *
857  * If the seqcount indicates that progress needs to be checked,
858  * re-submission is detected by checking whether the descriptor
859  * queue has enough descriptor for the txreq.
860  */
861 static inline unsigned sdma_progress(struct sdma_engine *sde, unsigned seq,
862 				     struct sdma_txreq *tx)
863 {
864 	if (read_seqretry(&sde->head_lock, seq)) {
865 		sde->desc_avail = sdma_descq_freecnt(sde);
866 		if (tx->num_desc > sde->desc_avail)
867 			return 0;
868 		return 1;
869 	}
870 	return 0;
871 }
872 
873 /* for use by interrupt handling */
874 void sdma_engine_error(struct sdma_engine *sde, u64 status);
875 void sdma_engine_interrupt(struct sdma_engine *sde, u64 status);
876 
877 /*
878  *
879  * The diagram below details the relationship of the mapping structures
880  *
881  * Since the mapping now allows for non-uniform engines per vl, the
882  * number of engines for a vl is either the vl_engines[vl] or
883  * a computation based on num_sdma/num_vls:
884  *
885  * For example:
886  * nactual = vl_engines ? vl_engines[vl] : num_sdma/num_vls
887  *
888  * n = roundup to next highest power of 2 using nactual
889  *
890  * In the case where there are num_sdma/num_vls doesn't divide
891  * evenly, the extras are added from the last vl downward.
892  *
893  * For the case where n > nactual, the engines are assigned
894  * in a round robin fashion wrapping back to the first engine
895  * for a particular vl.
896  *
897  *               dd->sdma_map
898  *                    |                                   sdma_map_elem[0]
899  *                    |                                +--------------------+
900  *                    v                                |       mask         |
901  *               sdma_vl_map                           |--------------------|
902  *      +--------------------------+                   | sde[0] -> eng 1    |
903  *      |    list (RCU)            |                   |--------------------|
904  *      |--------------------------|                 ->| sde[1] -> eng 2    |
905  *      |    mask                  |              --/  |--------------------|
906  *      |--------------------------|            -/     |        *           |
907  *      |    actual_vls (max 8)    |          -/       |--------------------|
908  *      |--------------------------|       --/         | sde[n-1] -> eng n  |
909  *      |    vls (max 8)           |     -/            +--------------------+
910  *      |--------------------------|  --/
911  *      |    map[0]                |-/
912  *      |--------------------------|                   +---------------------+
913  *      |    map[1]                |---                |       mask          |
914  *      |--------------------------|   \----           |---------------------|
915  *      |           *              |        \--        | sde[0] -> eng 1+n   |
916  *      |           *              |           \----   |---------------------|
917  *      |           *              |                \->| sde[1] -> eng 2+n   |
918  *      |--------------------------|                   |---------------------|
919  *      |   map[vls - 1]           |-                  |         *           |
920  *      +--------------------------+ \-                |---------------------|
921  *                                     \-              | sde[m-1] -> eng m+n |
922  *                                       \             +---------------------+
923  *                                        \-
924  *                                          \
925  *                                           \-        +----------------------+
926  *                                             \-      |       mask           |
927  *                                               \     |----------------------|
928  *                                                \-   | sde[0] -> eng 1+m+n  |
929  *                                                  \- |----------------------|
930  *                                                    >| sde[1] -> eng 2+m+n  |
931  *                                                     |----------------------|
932  *                                                     |         *            |
933  *                                                     |----------------------|
934  *                                                     | sde[o-1] -> eng o+m+n|
935  *                                                     +----------------------+
936  *
937  */
938 
939 /**
940  * struct sdma_map_elem - mapping for a vl
941  * @mask - selector mask
942  * @sde - array of engines for this vl
943  *
944  * The mask is used to "mod" the selector
945  * to produce index into the trailing
946  * array of sdes.
947  */
948 struct sdma_map_elem {
949 	u32 mask;
950 	struct sdma_engine *sde[];
951 };
952 
953 /**
954  * struct sdma_map_el - mapping for a vl
955  * @engine_to_vl - map of an engine to a vl
956  * @list - rcu head for free callback
957  * @mask - vl mask to "mod" the vl to produce an index to map array
958  * @actual_vls - number of vls
959  * @vls - number of vls rounded to next power of 2
960  * @map - array of sdma_map_elem entries
961  *
962  * This is the parent mapping structure.  The trailing
963  * members of the struct point to sdma_map_elem entries, which
964  * in turn point to an array of sde's for that vl.
965  */
966 struct sdma_vl_map {
967 	s8 engine_to_vl[TXE_NUM_SDMA_ENGINES];
968 	struct rcu_head list;
969 	u32 mask;
970 	u8 actual_vls;
971 	u8 vls;
972 	struct sdma_map_elem *map[];
973 };
974 
975 int sdma_map_init(
976 	struct hfi1_devdata *dd,
977 	u8 port,
978 	u8 num_vls,
979 	u8 *vl_engines);
980 
981 /* slow path */
982 void _sdma_engine_progress_schedule(struct sdma_engine *sde);
983 
984 /**
985  * sdma_engine_progress_schedule() - schedule progress on engine
986  * @sde: sdma_engine to schedule progress
987  *
988  * This is the fast path.
989  *
990  */
991 static inline void sdma_engine_progress_schedule(
992 	struct sdma_engine *sde)
993 {
994 	if (!sde || sdma_descq_inprocess(sde) < (sde->descq_cnt / 8))
995 		return;
996 	_sdma_engine_progress_schedule(sde);
997 }
998 
999 struct sdma_engine *sdma_select_engine_sc(
1000 	struct hfi1_devdata *dd,
1001 	u32 selector,
1002 	u8 sc5);
1003 
1004 struct sdma_engine *sdma_select_engine_vl(
1005 	struct hfi1_devdata *dd,
1006 	u32 selector,
1007 	u8 vl);
1008 
1009 struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd,
1010 					    u32 selector, u8 vl);
1011 ssize_t sdma_get_cpu_to_sde_map(struct sdma_engine *sde, char *buf);
1012 ssize_t sdma_set_cpu_to_sde_map(struct sdma_engine *sde, const char *buf,
1013 				size_t count);
1014 int sdma_engine_get_vl(struct sdma_engine *sde);
1015 void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *);
1016 void sdma_seqfile_dump_cpu_list(struct seq_file *s, struct hfi1_devdata *dd,
1017 				unsigned long cpuid);
1018 
1019 #ifdef CONFIG_SDMA_VERBOSITY
1020 void sdma_dumpstate(struct sdma_engine *);
1021 #endif
1022 static inline char *slashstrip(char *s)
1023 {
1024 	char *r = s;
1025 
1026 	while (*s)
1027 		if (*s++ == '/')
1028 			r = s;
1029 	return r;
1030 }
1031 
1032 u16 sdma_get_descq_cnt(void);
1033 
1034 extern uint mod_num_sdma;
1035 
1036 void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid);
1037 
1038 void system_descriptor_complete(struct hfi1_devdata *dd, struct sdma_desc *descp);
1039 #endif
1040