1/*-
2 * Copyright (c) 2016 Alexander Motin <mav@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 */
28
29#ifndef _NTB_H_
30#define _NTB_H_
31
32#include "ntb_if.h"
33
34extern devclass_t ntb_hw_devclass;
35SYSCTL_DECL(_hw_ntb);
36
37int ntb_register_device(device_t ntb);
38int ntb_unregister_device(device_t ntb);
39int ntb_child_location_str(device_t dev, device_t child, char *buf,
40    size_t buflen);
41int ntb_print_child(device_t dev, device_t child);
42bus_dma_tag_t ntb_get_dma_tag(device_t bus, device_t child);
43
44/*
45 * ntb_link_event() - notify driver context of a change in link status
46 * @ntb:        NTB device context
47 *
48 * Notify the driver context that the link status may have changed.  The driver
49 * should call intb_link_is_up() to get the current status.
50 */
51void ntb_link_event(device_t ntb);
52
53/*
54 * ntb_db_event() - notify driver context of a doorbell event
55 * @ntb:        NTB device context
56 * @vector:     Interrupt vector number
57 *
58 * Notify the driver context of a doorbell event.  If hardware supports
59 * multiple interrupt vectors for doorbells, the vector number indicates which
60 * vector received the interrupt.  The vector number is relative to the first
61 * vector used for doorbells, starting at zero, and must be less than
62 * ntb_db_vector_count().  The driver may call ntb_db_read() to check which
63 * doorbell bits need service, and ntb_db_vector_mask() to determine which of
64 * those bits are associated with the vector number.
65 */
66void ntb_db_event(device_t ntb, uint32_t vec);
67
68/**
69 * ntb_port_number() - get the local port number
70 * @ntb:        NTB device context.
71 *
72 * Hardware driver returns local port number in compliance with topology.
73 *
74 * Return: the local port number
75 */
76int ntb_port_number(device_t ntb);
77
78/**
79 * ntb_port_count() - get the number of peer device ports
80 * @ntb:        NTB device context.
81 *
82 * By default hardware driver supports just one peer device.
83 *
84 * Return: the number of peer ports
85 */
86int ntb_peer_port_count(device_t ntb);
87
88/**
89 * ntb_peer_port_number() - get the peer port by given index
90 * @ntb:        NTB device context.
91 * @idx:        Peer port index (should be zero for now).
92 *
93 * By default hardware driver supports just one peer device, so this method
94 * shall return the corresponding value.
95 *
96 * Return: the peer device port or an error number
97 */
98int ntb_peer_port_number(device_t ntb, int pidx);
99
100/*
101 * ntb_peer_port_idx() - get the peer device port index by given port
102 *                       number
103 * @ntb:        NTB device context.
104 * @port:       Peer port number
105 *
106 * By default hardware driver supports just one peer device, so given a
107 * valid peer port number, the return value shall be zero.
108 *
109 * Return: the peer port index or an error number
110 */
111int ntb_peer_port_idx(device_t ntb, int port);
112
113/*
114 * ntb_link_is_up() - get the current ntb link state
115 * @ntb:        NTB device context
116 * @speed:      OUT - The link speed expressed as PCIe generation number
117 * @width:      OUT - The link width expressed as the number of PCIe lanes
118 *
119 * RETURNS: true or false based on the hardware link state
120 */
121bool ntb_link_is_up(device_t ntb, enum ntb_speed *speed, enum ntb_width *width);
122
123/*
124 * ntb_link_enable() - enable the link on the secondary side of the ntb
125 * @ntb:        NTB device context
126 * @max_speed:  The maximum link speed expressed as PCIe generation number[0]
127 * @max_width:  The maximum link width expressed as the number of PCIe lanes[0]
128 *
129 * Enable the link on the secondary side of the ntb.  This can only be done
130 * from the primary side of the ntb in primary or b2b topology.  The ntb device
131 * should train the link to its maximum speed and width, or the requested speed
132 * and width, whichever is smaller, if supported.
133 *
134 * Return: Zero on success, otherwise an error number.
135 *
136 * [0]: Only NTB_SPEED_AUTO and NTB_WIDTH_AUTO are valid inputs; other speed
137 *      and width input will be ignored.
138 */
139int ntb_link_enable(device_t ntb, enum ntb_speed speed, enum ntb_width width);
140
141/*
142 * ntb_link_disable() - disable the link on the secondary side of the ntb
143 * @ntb:        NTB device context
144 *
145 * Disable the link on the secondary side of the ntb.  This can only be done
146 * from the primary side of the ntb in primary or b2b topology.  The ntb device
147 * should disable the link.  Returning from this call must indicate that a
148 * barrier has passed, though with no more writes may pass in either direction
149 * across the link, except if this call returns an error number.
150 *
151 * Return: Zero on success, otherwise an error number.
152 */
153int ntb_link_disable(device_t ntb);
154
155/*
156 * get enable status of the link on the secondary side of the ntb
157 */
158bool ntb_link_enabled(device_t ntb);
159
160/*
161 * ntb_set_ctx() - associate a driver context with an ntb device
162 * @ntb:        NTB device context
163 * @ctx:        Driver context
164 * @ctx_ops:    Driver context operations
165 *
166 * Associate a driver context and operations with a ntb device.  The context is
167 * provided by the client driver, and the driver may associate a different
168 * context with each ntb device.
169 *
170 * Return: Zero if the context is associated, otherwise an error number.
171 */
172int ntb_set_ctx(device_t ntb, void *ctx, const struct ntb_ctx_ops *ctx_ops);
173
174/*
175 * ntb_set_ctx() - get a driver context associated with an ntb device
176 * @ntb:        NTB device context
177 * @ctx_ops:    Driver context operations
178 *
179 * Get a driver context and operations associated with a ntb device.
180 */
181void * ntb_get_ctx(device_t ntb, const struct ntb_ctx_ops **ctx_ops);
182
183/*
184 * ntb_clear_ctx() - disassociate any driver context from an ntb device
185 * @ntb:        NTB device context
186 *
187 * Clear any association that may exist between a driver context and the ntb
188 * device.
189 */
190void ntb_clear_ctx(device_t ntb);
191
192/*
193 * ntb_mw_count() - Get the number of memory windows available for KPI
194 * consumers.
195 *
196 * (Excludes any MW wholly reserved for register access.)
197 */
198uint8_t ntb_mw_count(device_t ntb);
199
200/*
201 * ntb_mw_get_range() - get the range of a memory window
202 * @ntb:        NTB device context
203 * @idx:        Memory window number
204 * @base:       OUT - the base address for mapping the memory window
205 * @size:       OUT - the size for mapping the memory window
206 * @align:      OUT - the base alignment for translating the memory window
207 * @align_size: OUT - the size alignment for translating the memory window
208 *
209 * Get the range of a memory window.  NULL may be given for any output
210 * parameter if the value is not needed.  The base and size may be used for
211 * mapping the memory window, to access the peer memory.  The alignment and
212 * size may be used for translating the memory window, for the peer to access
213 * memory on the local system.
214 *
215 * Return: Zero on success, otherwise an error number.
216 */
217int ntb_mw_get_range(device_t ntb, unsigned mw_idx, vm_paddr_t *base,
218    caddr_t *vbase, size_t *size, size_t *align, size_t *align_size,
219    bus_addr_t *plimit);
220
221/*
222 * ntb_mw_set_trans() - set the translation of a memory window
223 * @ntb:        NTB device context
224 * @idx:        Memory window number
225 * @addr:       The dma address local memory to expose to the peer
226 * @size:       The size of the local memory to expose to the peer
227 *
228 * Set the translation of a memory window.  The peer may access local memory
229 * through the window starting at the address, up to the size.  The address
230 * must be aligned to the alignment specified by ntb_mw_get_range().  The size
231 * must be aligned to the size alignment specified by ntb_mw_get_range().  The
232 * address must be below the plimit specified by ntb_mw_get_range() (i.e. for
233 * 32-bit BARs).
234 *
235 * Return: Zero on success, otherwise an error number.
236 */
237int ntb_mw_set_trans(device_t ntb, unsigned mw_idx, bus_addr_t addr,
238    size_t size);
239
240/*
241 * ntb_mw_clear_trans() - clear the translation of a memory window
242 * @ntb:	NTB device context
243 * @idx:	Memory window number
244 *
245 * Clear the translation of a memory window.  The peer may no longer access
246 * local memory through the window.
247 *
248 * Return: Zero on success, otherwise an error number.
249 */
250int ntb_mw_clear_trans(device_t ntb, unsigned mw_idx);
251
252/*
253 * ntb_mw_get_wc - Get the write-combine status of a memory window
254 *
255 * Returns:  Zero on success, setting *wc; otherwise an error number (e.g. if
256 * idx is an invalid memory window).
257 *
258 * Mode is a VM_MEMATTR_* type.
259 */
260int ntb_mw_get_wc(device_t ntb, unsigned mw_idx, vm_memattr_t *mode);
261
262/*
263 * ntb_mw_set_wc - Set the write-combine status of a memory window
264 *
265 * If 'mode' matches the current status, this does nothing and succeeds.  Mode
266 * is a VM_MEMATTR_* type.
267 *
268 * Returns:  Zero on success, setting the caching attribute on the virtual
269 * mapping of the BAR; otherwise an error number (e.g. if idx is an invalid
270 * memory window, or if changing the caching attribute fails).
271 */
272int ntb_mw_set_wc(device_t ntb, unsigned mw_idx, vm_memattr_t mode);
273
274/*
275 * ntb_spad_count() - get the total scratch regs usable
276 * @ntb: pointer to ntb_softc instance
277 *
278 * This function returns the max 32bit scratchpad registers usable by the
279 * upper layer.
280 *
281 * RETURNS: total number of scratch pad registers available
282 */
283uint8_t ntb_spad_count(device_t ntb);
284
285/*
286 * ntb_get_max_spads() - zero local scratch registers
287 * @ntb: pointer to ntb_softc instance
288 *
289 * This functions overwrites all local scratchpad registers with zeroes.
290 */
291void ntb_spad_clear(device_t ntb);
292
293/*
294 * ntb_spad_write() - write to the secondary scratchpad register
295 * @ntb: pointer to ntb_softc instance
296 * @idx: index to the scratchpad register, 0 based
297 * @val: the data value to put into the register
298 *
299 * This function allows writing of a 32bit value to the indexed scratchpad
300 * register. The register resides on the secondary (external) side.
301 *
302 * RETURNS: An appropriate ERRNO error value on error, or zero for success.
303 */
304int ntb_spad_write(device_t ntb, unsigned int idx, uint32_t val);
305
306/*
307 * ntb_spad_read() - read from the primary scratchpad register
308 * @ntb: pointer to ntb_softc instance
309 * @idx: index to scratchpad register, 0 based
310 * @val: pointer to 32bit integer for storing the register value
311 *
312 * This function allows reading of the 32bit scratchpad register on
313 * the primary (internal) side.
314 *
315 * RETURNS: An appropriate ERRNO error value on error, or zero for success.
316 */
317int ntb_spad_read(device_t ntb, unsigned int idx, uint32_t *val);
318
319/*
320 * ntb_peer_spad_write() - write to the secondary scratchpad register
321 * @ntb: pointer to ntb_softc instance
322 * @idx: index to the scratchpad register, 0 based
323 * @val: the data value to put into the register
324 *
325 * This function allows writing of a 32bit value to the indexed scratchpad
326 * register. The register resides on the secondary (external) side.
327 *
328 * RETURNS: An appropriate ERRNO error value on error, or zero for success.
329 */
330int ntb_peer_spad_write(device_t ntb, unsigned int idx, uint32_t val);
331
332/*
333 * ntb_peer_spad_read() - read from the primary scratchpad register
334 * @ntb: pointer to ntb_softc instance
335 * @idx: index to scratchpad register, 0 based
336 * @val: pointer to 32bit integer for storing the register value
337 *
338 * This function allows reading of the 32bit scratchpad register on
339 * the primary (internal) side.
340 *
341 * RETURNS: An appropriate ERRNO error value on error, or zero for success.
342 */
343int ntb_peer_spad_read(device_t ntb, unsigned int idx, uint32_t *val);
344
345/*
346 * ntb_db_valid_mask() - get a mask of doorbell bits supported by the ntb
347 * @ntb:	NTB device context
348 *
349 * Hardware may support different number or arrangement of doorbell bits.
350 *
351 * Return: A mask of doorbell bits supported by the ntb.
352 */
353uint64_t ntb_db_valid_mask(device_t ntb);
354
355/*
356 * ntb_db_vector_count() - get the number of doorbell interrupt vectors
357 * @ntb:	NTB device context.
358 *
359 * Hardware may support different number of interrupt vectors.
360 *
361 * Return: The number of doorbell interrupt vectors.
362 */
363int ntb_db_vector_count(device_t ntb);
364
365/*
366 * ntb_db_vector_mask() - get a mask of doorbell bits serviced by a vector
367 * @ntb:	NTB device context
368 * @vector:	Doorbell vector number
369 *
370 * Each interrupt vector may have a different number or arrangement of bits.
371 *
372 * Return: A mask of doorbell bits serviced by a vector.
373 */
374uint64_t ntb_db_vector_mask(device_t ntb, uint32_t vector);
375
376/*
377 * ntb_peer_db_addr() - address and size of the peer doorbell register
378 * @ntb:	NTB device context.
379 * @db_addr:	OUT - The address of the peer doorbell register.
380 * @db_size:	OUT - The number of bytes to write the peer doorbell register.
381 *
382 * Return the address of the peer doorbell register.  This may be used, for
383 * example, by drivers that offload memory copy operations to a dma engine.
384 * The drivers may wish to ring the peer doorbell at the completion of memory
385 * copy operations.  For efficiency, and to simplify ordering of operations
386 * between the dma memory copies and the ringing doorbell, the driver may
387 * append one additional dma memory copy with the doorbell register as the
388 * destination, after the memory copy operations.
389 *
390 * Return: Zero on success, otherwise an error number.
391 *
392 * Note that writing the peer doorbell via a memory window will *not* generate
393 * an interrupt on the remote host; that must be done separately.
394 */
395int ntb_peer_db_addr(device_t ntb, bus_addr_t *db_addr, vm_size_t *db_size);
396
397/*
398 * ntb_db_clear() - clear bits in the local doorbell register
399 * @ntb:	NTB device context.
400 * @db_bits:	Doorbell bits to clear.
401 *
402 * Clear bits in the local doorbell register, arming the bits for the next
403 * doorbell.
404 *
405 * Return: Zero on success, otherwise an error number.
406 */
407void ntb_db_clear(device_t ntb, uint64_t bits);
408
409/*
410 * ntb_db_clear_mask() - clear bits in the local doorbell mask
411 * @ntb:	NTB device context.
412 * @db_bits:	Doorbell bits to clear.
413 *
414 * Clear bits in the local doorbell mask register, allowing doorbell interrupts
415 * from being generated for those doorbell bits.  If a doorbell bit is already
416 * set at the time the mask is cleared, and the corresponding mask bit is
417 * changed from set to clear, then the ntb driver must ensure that
418 * ntb_db_event() is called.  If the hardware does not generate the interrupt
419 * on clearing the mask bit, then the driver must call ntb_db_event() anyway.
420 *
421 * Return: Zero on success, otherwise an error number.
422 */
423void ntb_db_clear_mask(device_t ntb, uint64_t bits);
424
425/*
426 * ntb_db_read() - read the local doorbell register
427 * @ntb:	NTB device context.
428 *
429 * Read the local doorbell register, and return the bits that are set.
430 *
431 * Return: The bits currently set in the local doorbell register.
432 */
433uint64_t ntb_db_read(device_t ntb);
434
435/*
436 * ntb_db_set_mask() - set bits in the local doorbell mask
437 * @ntb:	NTB device context.
438 * @db_bits:	Doorbell mask bits to set.
439 *
440 * Set bits in the local doorbell mask register, preventing doorbell interrupts
441 * from being generated for those doorbell bits.  Bits that were already set
442 * must remain set.
443 *
444 * Return: Zero on success, otherwise an error number.
445 */
446void ntb_db_set_mask(device_t ntb, uint64_t bits);
447
448/*
449 * ntb_peer_db_set() - Set the doorbell on the secondary/external side
450 * @ntb: pointer to ntb_softc instance
451 * @bit: doorbell bits to ring
452 *
453 * This function allows triggering of a doorbell on the secondary/external
454 * side that will initiate an interrupt on the remote host
455 */
456void ntb_peer_db_set(device_t ntb, uint64_t bits);
457
458#endif /* _NTB_H_ */
459