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1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Thunderbolt service API
4  *
5  * Copyright (C) 2014 Andreas Noever <andreas.noever@gmail.com>
6  * Copyright (C) 2017, Intel Corporation
7  * Authors: Michael Jamet <michael.jamet@intel.com>
8  *          Mika Westerberg <mika.westerberg@linux.intel.com>
9  */
10 
11 #ifndef THUNDERBOLT_H_
12 #define THUNDERBOLT_H_
13 
14 #include <linux/device.h>
15 #include <linux/idr.h>
16 #include <linux/list.h>
17 #include <linux/mutex.h>
18 #include <linux/mod_devicetable.h>
19 #include <linux/pci.h>
20 #include <linux/uuid.h>
21 #include <linux/workqueue.h>
22 
23 enum tb_cfg_pkg_type {
24 	TB_CFG_PKG_READ = 1,
25 	TB_CFG_PKG_WRITE = 2,
26 	TB_CFG_PKG_ERROR = 3,
27 	TB_CFG_PKG_NOTIFY_ACK = 4,
28 	TB_CFG_PKG_EVENT = 5,
29 	TB_CFG_PKG_XDOMAIN_REQ = 6,
30 	TB_CFG_PKG_XDOMAIN_RESP = 7,
31 	TB_CFG_PKG_OVERRIDE = 8,
32 	TB_CFG_PKG_RESET = 9,
33 	TB_CFG_PKG_ICM_EVENT = 10,
34 	TB_CFG_PKG_ICM_CMD = 11,
35 	TB_CFG_PKG_ICM_RESP = 12,
36 	TB_CFG_PKG_PREPARE_TO_SLEEP = 13,
37 };
38 
39 /**
40  * enum tb_security_level - Thunderbolt security level
41  * @TB_SECURITY_NONE: No security, legacy mode
42  * @TB_SECURITY_USER: User approval required at minimum
43  * @TB_SECURITY_SECURE: One time saved key required at minimum
44  * @TB_SECURITY_DPONLY: Only tunnel Display port (and USB)
45  * @TB_SECURITY_USBONLY: Only tunnel USB controller of the connected
46  *			 Thunderbolt dock (and Display Port). All PCIe
47  *			 links downstream of the dock are removed.
48  * @TB_SECURITY_NOPCIE: For USB4 systems this level is used when the
49  *			PCIe tunneling is disabled from the BIOS.
50  */
51 enum tb_security_level {
52 	TB_SECURITY_NONE,
53 	TB_SECURITY_USER,
54 	TB_SECURITY_SECURE,
55 	TB_SECURITY_DPONLY,
56 	TB_SECURITY_USBONLY,
57 	TB_SECURITY_NOPCIE,
58 };
59 
60 /**
61  * struct tb - main thunderbolt bus structure
62  * @dev: Domain device
63  * @lock: Big lock. Must be held when accessing any struct
64  *	  tb_switch / struct tb_port.
65  * @nhi: Pointer to the NHI structure
66  * @ctl: Control channel for this domain
67  * @wq: Ordered workqueue for all domain specific work
68  * @root_switch: Root switch of this domain
69  * @cm_ops: Connection manager specific operations vector
70  * @index: Linux assigned domain number
71  * @security_level: Current security level
72  * @nboot_acl: Number of boot ACLs the domain supports
73  * @privdata: Private connection manager specific data
74  */
75 struct tb {
76 	struct device dev;
77 	struct mutex lock;
78 	struct tb_nhi *nhi;
79 	struct tb_ctl *ctl;
80 	struct workqueue_struct *wq;
81 	struct tb_switch *root_switch;
82 	const struct tb_cm_ops *cm_ops;
83 	int index;
84 	enum tb_security_level security_level;
85 	size_t nboot_acl;
86 	unsigned long privdata[];
87 };
88 
89 extern struct bus_type tb_bus_type;
90 extern struct device_type tb_service_type;
91 extern struct device_type tb_xdomain_type;
92 
93 #define TB_LINKS_PER_PHY_PORT	2
94 
tb_phy_port_from_link(unsigned int link)95 static inline unsigned int tb_phy_port_from_link(unsigned int link)
96 {
97 	return (link - 1) / TB_LINKS_PER_PHY_PORT;
98 }
99 
100 /**
101  * struct tb_property_dir - XDomain property directory
102  * @uuid: Directory UUID or %NULL if root directory
103  * @properties: List of properties in this directory
104  *
105  * User needs to provide serialization if needed.
106  */
107 struct tb_property_dir {
108 	const uuid_t *uuid;
109 	struct list_head properties;
110 };
111 
112 enum tb_property_type {
113 	TB_PROPERTY_TYPE_UNKNOWN = 0x00,
114 	TB_PROPERTY_TYPE_DIRECTORY = 0x44,
115 	TB_PROPERTY_TYPE_DATA = 0x64,
116 	TB_PROPERTY_TYPE_TEXT = 0x74,
117 	TB_PROPERTY_TYPE_VALUE = 0x76,
118 };
119 
120 #define TB_PROPERTY_KEY_SIZE	8
121 
122 /**
123  * struct tb_property - XDomain property
124  * @list: Used to link properties together in a directory
125  * @key: Key for the property (always terminated).
126  * @type: Type of the property
127  * @length: Length of the property data in dwords
128  * @value: Property value
129  *
130  * Users use @type to determine which field in @value is filled.
131  */
132 struct tb_property {
133 	struct list_head list;
134 	char key[TB_PROPERTY_KEY_SIZE + 1];
135 	enum tb_property_type type;
136 	size_t length;
137 	union {
138 		struct tb_property_dir *dir;
139 		u8 *data;
140 		char *text;
141 		u32 immediate;
142 	} value;
143 };
144 
145 struct tb_property_dir *tb_property_parse_dir(const u32 *block,
146 					      size_t block_len);
147 ssize_t tb_property_format_dir(const struct tb_property_dir *dir, u32 *block,
148 			       size_t block_len);
149 struct tb_property_dir *tb_property_copy_dir(const struct tb_property_dir *dir);
150 struct tb_property_dir *tb_property_create_dir(const uuid_t *uuid);
151 void tb_property_free_dir(struct tb_property_dir *dir);
152 int tb_property_add_immediate(struct tb_property_dir *parent, const char *key,
153 			      u32 value);
154 int tb_property_add_data(struct tb_property_dir *parent, const char *key,
155 			 const void *buf, size_t buflen);
156 int tb_property_add_text(struct tb_property_dir *parent, const char *key,
157 			 const char *text);
158 int tb_property_add_dir(struct tb_property_dir *parent, const char *key,
159 			struct tb_property_dir *dir);
160 void tb_property_remove(struct tb_property *tb_property);
161 struct tb_property *tb_property_find(struct tb_property_dir *dir,
162 			const char *key, enum tb_property_type type);
163 struct tb_property *tb_property_get_next(struct tb_property_dir *dir,
164 					 struct tb_property *prev);
165 
166 #define tb_property_for_each(dir, property)			\
167 	for (property = tb_property_get_next(dir, NULL);	\
168 	     property;						\
169 	     property = tb_property_get_next(dir, property))
170 
171 int tb_register_property_dir(const char *key, struct tb_property_dir *dir);
172 void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir);
173 
174 /**
175  * struct tb_xdomain - Cross-domain (XDomain) connection
176  * @dev: XDomain device
177  * @tb: Pointer to the domain
178  * @remote_uuid: UUID of the remote domain (host)
179  * @local_uuid: Cached local UUID
180  * @route: Route string the other domain can be reached
181  * @vendor: Vendor ID of the remote domain
182  * @device: Device ID of the demote domain
183  * @local_max_hopid: Maximum input HopID of this host
184  * @remote_max_hopid: Maximum input HopID of the remote host
185  * @lock: Lock to serialize access to the following fields of this structure
186  * @vendor_name: Name of the vendor (or %NULL if not known)
187  * @device_name: Name of the device (or %NULL if not known)
188  * @link_speed: Speed of the link in Gb/s
189  * @link_width: Width of the link (1 or 2)
190  * @is_unplugged: The XDomain is unplugged
191  * @needs_uuid: If the XDomain does not have @remote_uuid it will be
192  *		queried first
193  * @service_ids: Used to generate IDs for the services
194  * @in_hopids: Input HopIDs for DMA tunneling
195  * @out_hopids; Output HopIDs for DMA tunneling
196  * @local_property_block: Local block of properties
197  * @local_property_block_gen: Generation of @local_property_block
198  * @local_property_block_len: Length of the @local_property_block in dwords
199  * @remote_properties: Properties exported by the remote domain
200  * @remote_property_block_gen: Generation of @remote_properties
201  * @get_uuid_work: Work used to retrieve @remote_uuid
202  * @uuid_retries: Number of times left @remote_uuid is requested before
203  *		  giving up
204  * @get_properties_work: Work used to get remote domain properties
205  * @properties_retries: Number of times left to read properties
206  * @properties_changed_work: Work used to notify the remote domain that
207  *			     our properties have changed
208  * @properties_changed_retries: Number of times left to send properties
209  *				changed notification
210  * @link: Root switch link the remote domain is connected (ICM only)
211  * @depth: Depth in the chain the remote domain is connected (ICM only)
212  *
213  * This structure represents connection across two domains (hosts).
214  * Each XDomain contains zero or more services which are exposed as
215  * &struct tb_service objects.
216  *
217  * Service drivers may access this structure if they need to enumerate
218  * non-standard properties but they need hold @lock when doing so
219  * because properties can be changed asynchronously in response to
220  * changes in the remote domain.
221  */
222 struct tb_xdomain {
223 	struct device dev;
224 	struct tb *tb;
225 	uuid_t *remote_uuid;
226 	const uuid_t *local_uuid;
227 	u64 route;
228 	u16 vendor;
229 	u16 device;
230 	unsigned int local_max_hopid;
231 	unsigned int remote_max_hopid;
232 	struct mutex lock;
233 	const char *vendor_name;
234 	const char *device_name;
235 	unsigned int link_speed;
236 	unsigned int link_width;
237 	bool is_unplugged;
238 	bool needs_uuid;
239 	struct ida service_ids;
240 	struct ida in_hopids;
241 	struct ida out_hopids;
242 	u32 *local_property_block;
243 	u32 local_property_block_gen;
244 	u32 local_property_block_len;
245 	struct tb_property_dir *remote_properties;
246 	u32 remote_property_block_gen;
247 	struct delayed_work get_uuid_work;
248 	int uuid_retries;
249 	struct delayed_work get_properties_work;
250 	int properties_retries;
251 	struct delayed_work properties_changed_work;
252 	int properties_changed_retries;
253 	u8 link;
254 	u8 depth;
255 };
256 
257 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd);
258 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd);
259 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid);
260 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid);
261 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid);
262 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid);
263 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
264 			    int transmit_ring, int receive_path,
265 			    int receive_ring);
266 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
267 			     int transmit_ring, int receive_path,
268 			     int receive_ring);
269 
tb_xdomain_disable_all_paths(struct tb_xdomain * xd)270 static inline int tb_xdomain_disable_all_paths(struct tb_xdomain *xd)
271 {
272 	return tb_xdomain_disable_paths(xd, -1, -1, -1, -1);
273 }
274 
275 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid);
276 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route);
277 
278 static inline struct tb_xdomain *
tb_xdomain_find_by_uuid_locked(struct tb * tb,const uuid_t * uuid)279 tb_xdomain_find_by_uuid_locked(struct tb *tb, const uuid_t *uuid)
280 {
281 	struct tb_xdomain *xd;
282 
283 	mutex_lock(&tb->lock);
284 	xd = tb_xdomain_find_by_uuid(tb, uuid);
285 	mutex_unlock(&tb->lock);
286 
287 	return xd;
288 }
289 
290 static inline struct tb_xdomain *
tb_xdomain_find_by_route_locked(struct tb * tb,u64 route)291 tb_xdomain_find_by_route_locked(struct tb *tb, u64 route)
292 {
293 	struct tb_xdomain *xd;
294 
295 	mutex_lock(&tb->lock);
296 	xd = tb_xdomain_find_by_route(tb, route);
297 	mutex_unlock(&tb->lock);
298 
299 	return xd;
300 }
301 
tb_xdomain_get(struct tb_xdomain * xd)302 static inline struct tb_xdomain *tb_xdomain_get(struct tb_xdomain *xd)
303 {
304 	if (xd)
305 		get_device(&xd->dev);
306 	return xd;
307 }
308 
tb_xdomain_put(struct tb_xdomain * xd)309 static inline void tb_xdomain_put(struct tb_xdomain *xd)
310 {
311 	if (xd)
312 		put_device(&xd->dev);
313 }
314 
tb_is_xdomain(const struct device * dev)315 static inline bool tb_is_xdomain(const struct device *dev)
316 {
317 	return dev->type == &tb_xdomain_type;
318 }
319 
tb_to_xdomain(struct device * dev)320 static inline struct tb_xdomain *tb_to_xdomain(struct device *dev)
321 {
322 	if (tb_is_xdomain(dev))
323 		return container_of(dev, struct tb_xdomain, dev);
324 	return NULL;
325 }
326 
327 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
328 			size_t size, enum tb_cfg_pkg_type type);
329 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
330 		       size_t request_size, enum tb_cfg_pkg_type request_type,
331 		       void *response, size_t response_size,
332 		       enum tb_cfg_pkg_type response_type,
333 		       unsigned int timeout_msec);
334 
335 /**
336  * tb_protocol_handler - Protocol specific handler
337  * @uuid: XDomain messages with this UUID are dispatched to this handler
338  * @callback: Callback called with the XDomain message. Returning %1
339  *	      here tells the XDomain core that the message was handled
340  *	      by this handler and should not be forwared to other
341  *	      handlers.
342  * @data: Data passed with the callback
343  * @list: Handlers are linked using this
344  *
345  * Thunderbolt services can hook into incoming XDomain requests by
346  * registering protocol handler. Only limitation is that the XDomain
347  * discovery protocol UUID cannot be registered since it is handled by
348  * the core XDomain code.
349  *
350  * The @callback must check that the message is really directed to the
351  * service the driver implements.
352  */
353 struct tb_protocol_handler {
354 	const uuid_t *uuid;
355 	int (*callback)(const void *buf, size_t size, void *data);
356 	void *data;
357 	struct list_head list;
358 };
359 
360 int tb_register_protocol_handler(struct tb_protocol_handler *handler);
361 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler);
362 
363 /**
364  * struct tb_service - Thunderbolt service
365  * @dev: XDomain device
366  * @id: ID of the service (shown in sysfs)
367  * @key: Protocol key from the properties directory
368  * @prtcid: Protocol ID from the properties directory
369  * @prtcvers: Protocol version from the properties directory
370  * @prtcrevs: Protocol software revision from the properties directory
371  * @prtcstns: Protocol settings mask from the properties directory
372  * @debugfs_dir: Pointer to the service debugfs directory. Always created
373  *		 when debugfs is enabled. Can be used by service drivers to
374  *		 add their own entries under the service.
375  *
376  * Each domain exposes set of services it supports as collection of
377  * properties. For each service there will be one corresponding
378  * &struct tb_service. Service drivers are bound to these.
379  */
380 struct tb_service {
381 	struct device dev;
382 	int id;
383 	const char *key;
384 	u32 prtcid;
385 	u32 prtcvers;
386 	u32 prtcrevs;
387 	u32 prtcstns;
388 	struct dentry *debugfs_dir;
389 };
390 
tb_service_get(struct tb_service * svc)391 static inline struct tb_service *tb_service_get(struct tb_service *svc)
392 {
393 	if (svc)
394 		get_device(&svc->dev);
395 	return svc;
396 }
397 
tb_service_put(struct tb_service * svc)398 static inline void tb_service_put(struct tb_service *svc)
399 {
400 	if (svc)
401 		put_device(&svc->dev);
402 }
403 
tb_is_service(const struct device * dev)404 static inline bool tb_is_service(const struct device *dev)
405 {
406 	return dev->type == &tb_service_type;
407 }
408 
tb_to_service(struct device * dev)409 static inline struct tb_service *tb_to_service(struct device *dev)
410 {
411 	if (tb_is_service(dev))
412 		return container_of(dev, struct tb_service, dev);
413 	return NULL;
414 }
415 
416 /**
417  * tb_service_driver - Thunderbolt service driver
418  * @driver: Driver structure
419  * @probe: Called when the driver is probed
420  * @remove: Called when the driver is removed (optional)
421  * @shutdown: Called at shutdown time to stop the service (optional)
422  * @id_table: Table of service identifiers the driver supports
423  */
424 struct tb_service_driver {
425 	struct device_driver driver;
426 	int (*probe)(struct tb_service *svc, const struct tb_service_id *id);
427 	void (*remove)(struct tb_service *svc);
428 	void (*shutdown)(struct tb_service *svc);
429 	const struct tb_service_id *id_table;
430 };
431 
432 #define TB_SERVICE(key, id)				\
433 	.match_flags = TBSVC_MATCH_PROTOCOL_KEY |	\
434 		       TBSVC_MATCH_PROTOCOL_ID,		\
435 	.protocol_key = (key),				\
436 	.protocol_id = (id)
437 
438 int tb_register_service_driver(struct tb_service_driver *drv);
439 void tb_unregister_service_driver(struct tb_service_driver *drv);
440 
tb_service_get_drvdata(const struct tb_service * svc)441 static inline void *tb_service_get_drvdata(const struct tb_service *svc)
442 {
443 	return dev_get_drvdata(&svc->dev);
444 }
445 
tb_service_set_drvdata(struct tb_service * svc,void * data)446 static inline void tb_service_set_drvdata(struct tb_service *svc, void *data)
447 {
448 	dev_set_drvdata(&svc->dev, data);
449 }
450 
tb_service_parent(struct tb_service * svc)451 static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
452 {
453 	return tb_to_xdomain(svc->dev.parent);
454 }
455 
456 /**
457  * struct tb_nhi - thunderbolt native host interface
458  * @lock: Must be held during ring creation/destruction. Is acquired by
459  *	  interrupt_work when dispatching interrupts to individual rings.
460  * @pdev: Pointer to the PCI device
461  * @ops: NHI specific optional ops
462  * @iobase: MMIO space of the NHI
463  * @tx_rings: All Tx rings available on this host controller
464  * @rx_rings: All Rx rings available on this host controller
465  * @msix_ida: Used to allocate MSI-X vectors for rings
466  * @going_away: The host controller device is about to disappear so when
467  *		this flag is set, avoid touching the hardware anymore.
468  * @interrupt_work: Work scheduled to handle ring interrupt when no
469  *		    MSI-X is used.
470  * @hop_count: Number of rings (end point hops) supported by NHI.
471  * @quirks: NHI specific quirks if any
472  */
473 struct tb_nhi {
474 	spinlock_t lock;
475 	struct pci_dev *pdev;
476 	const struct tb_nhi_ops *ops;
477 	void __iomem *iobase;
478 	struct tb_ring **tx_rings;
479 	struct tb_ring **rx_rings;
480 	struct ida msix_ida;
481 	bool going_away;
482 	struct work_struct interrupt_work;
483 	u32 hop_count;
484 	unsigned long quirks;
485 };
486 
487 /**
488  * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
489  * @lock: Lock serializing actions to this ring. Must be acquired after
490  *	  nhi->lock.
491  * @nhi: Pointer to the native host controller interface
492  * @size: Size of the ring
493  * @hop: Hop (DMA channel) associated with this ring
494  * @head: Head of the ring (write next descriptor here)
495  * @tail: Tail of the ring (complete next descriptor here)
496  * @descriptors: Allocated descriptors for this ring
497  * @queue: Queue holding frames to be transferred over this ring
498  * @in_flight: Queue holding frames that are currently in flight
499  * @work: Interrupt work structure
500  * @is_tx: Is the ring Tx or Rx
501  * @running: Is the ring running
502  * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
503  * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
504  * @flags: Ring specific flags
505  * @e2e_tx_hop: Transmit HopID when E2E is enabled. Only applicable to
506  *		RX ring. For TX ring this should be set to %0.
507  * @sof_mask: Bit mask used to detect start of frame PDF
508  * @eof_mask: Bit mask used to detect end of frame PDF
509  * @start_poll: Called when ring interrupt is triggered to start
510  *		polling. Passing %NULL keeps the ring in interrupt mode.
511  * @poll_data: Data passed to @start_poll
512  */
513 struct tb_ring {
514 	spinlock_t lock;
515 	struct tb_nhi *nhi;
516 	int size;
517 	int hop;
518 	int head;
519 	int tail;
520 	struct ring_desc *descriptors;
521 	dma_addr_t descriptors_dma;
522 	struct list_head queue;
523 	struct list_head in_flight;
524 	struct work_struct work;
525 	bool is_tx:1;
526 	bool running:1;
527 	int irq;
528 	u8 vector;
529 	unsigned int flags;
530 	int e2e_tx_hop;
531 	u16 sof_mask;
532 	u16 eof_mask;
533 	void (*start_poll)(void *data);
534 	void *poll_data;
535 };
536 
537 /* Leave ring interrupt enabled on suspend */
538 #define RING_FLAG_NO_SUSPEND	BIT(0)
539 /* Configure the ring to be in frame mode */
540 #define RING_FLAG_FRAME		BIT(1)
541 /* Enable end-to-end flow control */
542 #define RING_FLAG_E2E		BIT(2)
543 
544 struct ring_frame;
545 typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
546 
547 /**
548  * enum ring_desc_flags - Flags for DMA ring descriptor
549  * %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only)
550  * %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only)
551  * %RING_DESC_COMPLETED: Descriptor completed (set by NHI)
552  * %RING_DESC_POSTED: Always set this
553  * %RING_DESC_BUFFER_OVERRUN: RX buffer overrun
554  * %RING_DESC_INTERRUPT: Request an interrupt on completion
555  */
556 enum ring_desc_flags {
557 	RING_DESC_ISOCH = 0x1,
558 	RING_DESC_CRC_ERROR = 0x1,
559 	RING_DESC_COMPLETED = 0x2,
560 	RING_DESC_POSTED = 0x4,
561 	RING_DESC_BUFFER_OVERRUN = 0x04,
562 	RING_DESC_INTERRUPT = 0x8,
563 };
564 
565 /**
566  * struct ring_frame - For use with ring_rx/ring_tx
567  * @buffer_phy: DMA mapped address of the frame
568  * @callback: Callback called when the frame is finished (optional)
569  * @list: Frame is linked to a queue using this
570  * @size: Size of the frame in bytes (%0 means %4096)
571  * @flags: Flags for the frame (see &enum ring_desc_flags)
572  * @eof: End of frame protocol defined field
573  * @sof: Start of frame protocol defined field
574  */
575 struct ring_frame {
576 	dma_addr_t buffer_phy;
577 	ring_cb callback;
578 	struct list_head list;
579 	u32 size:12;
580 	u32 flags:12;
581 	u32 eof:4;
582 	u32 sof:4;
583 };
584 
585 /* Minimum size for ring_rx */
586 #define TB_FRAME_SIZE		0x100
587 
588 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
589 				 unsigned int flags);
590 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
591 				 unsigned int flags, int e2e_tx_hop,
592 				 u16 sof_mask, u16 eof_mask,
593 				 void (*start_poll)(void *), void *poll_data);
594 void tb_ring_start(struct tb_ring *ring);
595 void tb_ring_stop(struct tb_ring *ring);
596 void tb_ring_free(struct tb_ring *ring);
597 
598 int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
599 
600 /**
601  * tb_ring_rx() - enqueue a frame on an RX ring
602  * @ring: Ring to enqueue the frame
603  * @frame: Frame to enqueue
604  *
605  * @frame->buffer, @frame->buffer_phy have to be set. The buffer must
606  * contain at least %TB_FRAME_SIZE bytes.
607  *
608  * @frame->callback will be invoked with @frame->size, @frame->flags,
609  * @frame->eof, @frame->sof set once the frame has been received.
610  *
611  * If ring_stop() is called after the packet has been enqueued
612  * @frame->callback will be called with canceled set to true.
613  *
614  * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
615  */
tb_ring_rx(struct tb_ring * ring,struct ring_frame * frame)616 static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
617 {
618 	WARN_ON(ring->is_tx);
619 	return __tb_ring_enqueue(ring, frame);
620 }
621 
622 /**
623  * tb_ring_tx() - enqueue a frame on an TX ring
624  * @ring: Ring the enqueue the frame
625  * @frame: Frame to enqueue
626  *
627  * @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and
628  * @frame->sof have to be set.
629  *
630  * @frame->callback will be invoked with once the frame has been transmitted.
631  *
632  * If ring_stop() is called after the packet has been enqueued @frame->callback
633  * will be called with canceled set to true.
634  *
635  * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
636  */
tb_ring_tx(struct tb_ring * ring,struct ring_frame * frame)637 static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
638 {
639 	WARN_ON(!ring->is_tx);
640 	return __tb_ring_enqueue(ring, frame);
641 }
642 
643 /* Used only when the ring is in polling mode */
644 struct ring_frame *tb_ring_poll(struct tb_ring *ring);
645 void tb_ring_poll_complete(struct tb_ring *ring);
646 
647 /**
648  * tb_ring_dma_device() - Return device used for DMA mapping
649  * @ring: Ring whose DMA device is retrieved
650  *
651  * Use this function when you are mapping DMA for buffers that are
652  * passed to the ring for sending/receiving.
653  */
tb_ring_dma_device(struct tb_ring * ring)654 static inline struct device *tb_ring_dma_device(struct tb_ring *ring)
655 {
656 	return &ring->nhi->pdev->dev;
657 }
658 
659 #endif /* THUNDERBOLT_H_ */
660