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  * @link_usb4: Downstream link is USB4
191  * @is_unplugged: The XDomain is unplugged
192  * @needs_uuid: If the XDomain does not have @remote_uuid it will be
193  *		queried first
194  * @service_ids: Used to generate IDs for the services
195  * @in_hopids: Input HopIDs for DMA tunneling
196  * @out_hopids; Output HopIDs for DMA tunneling
197  * @local_property_block: Local block of properties
198  * @local_property_block_gen: Generation of @local_property_block
199  * @local_property_block_len: Length of the @local_property_block in dwords
200  * @remote_properties: Properties exported by the remote domain
201  * @remote_property_block_gen: Generation of @remote_properties
202  * @state: Next XDomain discovery state to run
203  * @state_work: Work used to run the next state
204  * @state_retries: Number of retries remain for the state
205  * @properties_changed_work: Work used to notify the remote domain that
206  *			     our properties have changed
207  * @properties_changed_retries: Number of times left to send properties
208  *				changed notification
209  * @bonding_possible: True if lane bonding is possible on local side
210  * @target_link_width: Target link width from the remote host
211  * @link: Root switch link the remote domain is connected (ICM only)
212  * @depth: Depth in the chain the remote domain is connected (ICM only)
213  *
214  * This structure represents connection across two domains (hosts).
215  * Each XDomain contains zero or more services which are exposed as
216  * &struct tb_service objects.
217  *
218  * Service drivers may access this structure if they need to enumerate
219  * non-standard properties but they need hold @lock when doing so
220  * because properties can be changed asynchronously in response to
221  * changes in the remote domain.
222  */
223 struct tb_xdomain {
224 	struct device dev;
225 	struct tb *tb;
226 	uuid_t *remote_uuid;
227 	const uuid_t *local_uuid;
228 	u64 route;
229 	u16 vendor;
230 	u16 device;
231 	unsigned int local_max_hopid;
232 	unsigned int remote_max_hopid;
233 	struct mutex lock;
234 	const char *vendor_name;
235 	const char *device_name;
236 	unsigned int link_speed;
237 	unsigned int link_width;
238 	bool link_usb4;
239 	bool is_unplugged;
240 	bool needs_uuid;
241 	struct ida service_ids;
242 	struct ida in_hopids;
243 	struct ida out_hopids;
244 	u32 *local_property_block;
245 	u32 local_property_block_gen;
246 	u32 local_property_block_len;
247 	struct tb_property_dir *remote_properties;
248 	u32 remote_property_block_gen;
249 	int state;
250 	struct delayed_work state_work;
251 	int state_retries;
252 	struct delayed_work properties_changed_work;
253 	int properties_changed_retries;
254 	bool bonding_possible;
255 	u8 target_link_width;
256 	u8 link;
257 	u8 depth;
258 };
259 
260 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd);
261 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd);
262 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid);
263 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid);
264 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid);
265 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid);
266 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
267 			    int transmit_ring, int receive_path,
268 			    int receive_ring);
269 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
270 			     int transmit_ring, int receive_path,
271 			     int receive_ring);
272 
tb_xdomain_disable_all_paths(struct tb_xdomain * xd)273 static inline int tb_xdomain_disable_all_paths(struct tb_xdomain *xd)
274 {
275 	return tb_xdomain_disable_paths(xd, -1, -1, -1, -1);
276 }
277 
278 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid);
279 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route);
280 
281 static inline struct tb_xdomain *
tb_xdomain_find_by_uuid_locked(struct tb * tb,const uuid_t * uuid)282 tb_xdomain_find_by_uuid_locked(struct tb *tb, const uuid_t *uuid)
283 {
284 	struct tb_xdomain *xd;
285 
286 	mutex_lock(&tb->lock);
287 	xd = tb_xdomain_find_by_uuid(tb, uuid);
288 	mutex_unlock(&tb->lock);
289 
290 	return xd;
291 }
292 
293 static inline struct tb_xdomain *
tb_xdomain_find_by_route_locked(struct tb * tb,u64 route)294 tb_xdomain_find_by_route_locked(struct tb *tb, u64 route)
295 {
296 	struct tb_xdomain *xd;
297 
298 	mutex_lock(&tb->lock);
299 	xd = tb_xdomain_find_by_route(tb, route);
300 	mutex_unlock(&tb->lock);
301 
302 	return xd;
303 }
304 
tb_xdomain_get(struct tb_xdomain * xd)305 static inline struct tb_xdomain *tb_xdomain_get(struct tb_xdomain *xd)
306 {
307 	if (xd)
308 		get_device(&xd->dev);
309 	return xd;
310 }
311 
tb_xdomain_put(struct tb_xdomain * xd)312 static inline void tb_xdomain_put(struct tb_xdomain *xd)
313 {
314 	if (xd)
315 		put_device(&xd->dev);
316 }
317 
tb_is_xdomain(const struct device * dev)318 static inline bool tb_is_xdomain(const struct device *dev)
319 {
320 	return dev->type == &tb_xdomain_type;
321 }
322 
tb_to_xdomain(struct device * dev)323 static inline struct tb_xdomain *tb_to_xdomain(struct device *dev)
324 {
325 	if (tb_is_xdomain(dev))
326 		return container_of(dev, struct tb_xdomain, dev);
327 	return NULL;
328 }
329 
330 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
331 			size_t size, enum tb_cfg_pkg_type type);
332 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
333 		       size_t request_size, enum tb_cfg_pkg_type request_type,
334 		       void *response, size_t response_size,
335 		       enum tb_cfg_pkg_type response_type,
336 		       unsigned int timeout_msec);
337 
338 /**
339  * tb_protocol_handler - Protocol specific handler
340  * @uuid: XDomain messages with this UUID are dispatched to this handler
341  * @callback: Callback called with the XDomain message. Returning %1
342  *	      here tells the XDomain core that the message was handled
343  *	      by this handler and should not be forwared to other
344  *	      handlers.
345  * @data: Data passed with the callback
346  * @list: Handlers are linked using this
347  *
348  * Thunderbolt services can hook into incoming XDomain requests by
349  * registering protocol handler. Only limitation is that the XDomain
350  * discovery protocol UUID cannot be registered since it is handled by
351  * the core XDomain code.
352  *
353  * The @callback must check that the message is really directed to the
354  * service the driver implements.
355  */
356 struct tb_protocol_handler {
357 	const uuid_t *uuid;
358 	int (*callback)(const void *buf, size_t size, void *data);
359 	void *data;
360 	struct list_head list;
361 };
362 
363 int tb_register_protocol_handler(struct tb_protocol_handler *handler);
364 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler);
365 
366 /**
367  * struct tb_service - Thunderbolt service
368  * @dev: XDomain device
369  * @id: ID of the service (shown in sysfs)
370  * @key: Protocol key from the properties directory
371  * @prtcid: Protocol ID from the properties directory
372  * @prtcvers: Protocol version from the properties directory
373  * @prtcrevs: Protocol software revision from the properties directory
374  * @prtcstns: Protocol settings mask from the properties directory
375  * @debugfs_dir: Pointer to the service debugfs directory. Always created
376  *		 when debugfs is enabled. Can be used by service drivers to
377  *		 add their own entries under the service.
378  *
379  * Each domain exposes set of services it supports as collection of
380  * properties. For each service there will be one corresponding
381  * &struct tb_service. Service drivers are bound to these.
382  */
383 struct tb_service {
384 	struct device dev;
385 	int id;
386 	const char *key;
387 	u32 prtcid;
388 	u32 prtcvers;
389 	u32 prtcrevs;
390 	u32 prtcstns;
391 	struct dentry *debugfs_dir;
392 };
393 
tb_service_get(struct tb_service * svc)394 static inline struct tb_service *tb_service_get(struct tb_service *svc)
395 {
396 	if (svc)
397 		get_device(&svc->dev);
398 	return svc;
399 }
400 
tb_service_put(struct tb_service * svc)401 static inline void tb_service_put(struct tb_service *svc)
402 {
403 	if (svc)
404 		put_device(&svc->dev);
405 }
406 
tb_is_service(const struct device * dev)407 static inline bool tb_is_service(const struct device *dev)
408 {
409 	return dev->type == &tb_service_type;
410 }
411 
tb_to_service(struct device * dev)412 static inline struct tb_service *tb_to_service(struct device *dev)
413 {
414 	if (tb_is_service(dev))
415 		return container_of(dev, struct tb_service, dev);
416 	return NULL;
417 }
418 
419 /**
420  * tb_service_driver - Thunderbolt service driver
421  * @driver: Driver structure
422  * @probe: Called when the driver is probed
423  * @remove: Called when the driver is removed (optional)
424  * @shutdown: Called at shutdown time to stop the service (optional)
425  * @id_table: Table of service identifiers the driver supports
426  */
427 struct tb_service_driver {
428 	struct device_driver driver;
429 	int (*probe)(struct tb_service *svc, const struct tb_service_id *id);
430 	void (*remove)(struct tb_service *svc);
431 	void (*shutdown)(struct tb_service *svc);
432 	const struct tb_service_id *id_table;
433 };
434 
435 #define TB_SERVICE(key, id)				\
436 	.match_flags = TBSVC_MATCH_PROTOCOL_KEY |	\
437 		       TBSVC_MATCH_PROTOCOL_ID,		\
438 	.protocol_key = (key),				\
439 	.protocol_id = (id)
440 
441 int tb_register_service_driver(struct tb_service_driver *drv);
442 void tb_unregister_service_driver(struct tb_service_driver *drv);
443 
tb_service_get_drvdata(const struct tb_service * svc)444 static inline void *tb_service_get_drvdata(const struct tb_service *svc)
445 {
446 	return dev_get_drvdata(&svc->dev);
447 }
448 
tb_service_set_drvdata(struct tb_service * svc,void * data)449 static inline void tb_service_set_drvdata(struct tb_service *svc, void *data)
450 {
451 	dev_set_drvdata(&svc->dev, data);
452 }
453 
tb_service_parent(struct tb_service * svc)454 static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
455 {
456 	return tb_to_xdomain(svc->dev.parent);
457 }
458 
459 /**
460  * struct tb_nhi - thunderbolt native host interface
461  * @lock: Must be held during ring creation/destruction. Is acquired by
462  *	  interrupt_work when dispatching interrupts to individual rings.
463  * @pdev: Pointer to the PCI device
464  * @ops: NHI specific optional ops
465  * @iobase: MMIO space of the NHI
466  * @tx_rings: All Tx rings available on this host controller
467  * @rx_rings: All Rx rings available on this host controller
468  * @msix_ida: Used to allocate MSI-X vectors for rings
469  * @going_away: The host controller device is about to disappear so when
470  *		this flag is set, avoid touching the hardware anymore.
471  * @iommu_dma_protection: An IOMMU will isolate external-facing ports.
472  * @interrupt_work: Work scheduled to handle ring interrupt when no
473  *		    MSI-X is used.
474  * @hop_count: Number of rings (end point hops) supported by NHI.
475  * @quirks: NHI specific quirks if any
476  */
477 struct tb_nhi {
478 	spinlock_t lock;
479 	struct pci_dev *pdev;
480 	const struct tb_nhi_ops *ops;
481 	void __iomem *iobase;
482 	struct tb_ring **tx_rings;
483 	struct tb_ring **rx_rings;
484 	struct ida msix_ida;
485 	bool going_away;
486 	bool iommu_dma_protection;
487 	struct work_struct interrupt_work;
488 	u32 hop_count;
489 	unsigned long quirks;
490 };
491 
492 /**
493  * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
494  * @lock: Lock serializing actions to this ring. Must be acquired after
495  *	  nhi->lock.
496  * @nhi: Pointer to the native host controller interface
497  * @size: Size of the ring
498  * @hop: Hop (DMA channel) associated with this ring
499  * @head: Head of the ring (write next descriptor here)
500  * @tail: Tail of the ring (complete next descriptor here)
501  * @descriptors: Allocated descriptors for this ring
502  * @queue: Queue holding frames to be transferred over this ring
503  * @in_flight: Queue holding frames that are currently in flight
504  * @work: Interrupt work structure
505  * @is_tx: Is the ring Tx or Rx
506  * @running: Is the ring running
507  * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
508  * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
509  * @flags: Ring specific flags
510  * @e2e_tx_hop: Transmit HopID when E2E is enabled. Only applicable to
511  *		RX ring. For TX ring this should be set to %0.
512  * @sof_mask: Bit mask used to detect start of frame PDF
513  * @eof_mask: Bit mask used to detect end of frame PDF
514  * @start_poll: Called when ring interrupt is triggered to start
515  *		polling. Passing %NULL keeps the ring in interrupt mode.
516  * @poll_data: Data passed to @start_poll
517  */
518 struct tb_ring {
519 	spinlock_t lock;
520 	struct tb_nhi *nhi;
521 	int size;
522 	int hop;
523 	int head;
524 	int tail;
525 	struct ring_desc *descriptors;
526 	dma_addr_t descriptors_dma;
527 	struct list_head queue;
528 	struct list_head in_flight;
529 	struct work_struct work;
530 	bool is_tx:1;
531 	bool running:1;
532 	int irq;
533 	u8 vector;
534 	unsigned int flags;
535 	int e2e_tx_hop;
536 	u16 sof_mask;
537 	u16 eof_mask;
538 	void (*start_poll)(void *data);
539 	void *poll_data;
540 };
541 
542 /* Leave ring interrupt enabled on suspend */
543 #define RING_FLAG_NO_SUSPEND	BIT(0)
544 /* Configure the ring to be in frame mode */
545 #define RING_FLAG_FRAME		BIT(1)
546 /* Enable end-to-end flow control */
547 #define RING_FLAG_E2E		BIT(2)
548 
549 struct ring_frame;
550 typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
551 
552 /**
553  * enum ring_desc_flags - Flags for DMA ring descriptor
554  * %RING_DESC_ISOCH: Enable isonchronous DMA (Tx only)
555  * %RING_DESC_CRC_ERROR: In frame mode CRC check failed for the frame (Rx only)
556  * %RING_DESC_COMPLETED: Descriptor completed (set by NHI)
557  * %RING_DESC_POSTED: Always set this
558  * %RING_DESC_BUFFER_OVERRUN: RX buffer overrun
559  * %RING_DESC_INTERRUPT: Request an interrupt on completion
560  */
561 enum ring_desc_flags {
562 	RING_DESC_ISOCH = 0x1,
563 	RING_DESC_CRC_ERROR = 0x1,
564 	RING_DESC_COMPLETED = 0x2,
565 	RING_DESC_POSTED = 0x4,
566 	RING_DESC_BUFFER_OVERRUN = 0x04,
567 	RING_DESC_INTERRUPT = 0x8,
568 };
569 
570 /**
571  * struct ring_frame - For use with ring_rx/ring_tx
572  * @buffer_phy: DMA mapped address of the frame
573  * @callback: Callback called when the frame is finished (optional)
574  * @list: Frame is linked to a queue using this
575  * @size: Size of the frame in bytes (%0 means %4096)
576  * @flags: Flags for the frame (see &enum ring_desc_flags)
577  * @eof: End of frame protocol defined field
578  * @sof: Start of frame protocol defined field
579  */
580 struct ring_frame {
581 	dma_addr_t buffer_phy;
582 	ring_cb callback;
583 	struct list_head list;
584 	u32 size:12;
585 	u32 flags:12;
586 	u32 eof:4;
587 	u32 sof:4;
588 };
589 
590 /* Minimum size for ring_rx */
591 #define TB_FRAME_SIZE		0x100
592 
593 struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
594 				 unsigned int flags);
595 struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
596 				 unsigned int flags, int e2e_tx_hop,
597 				 u16 sof_mask, u16 eof_mask,
598 				 void (*start_poll)(void *), void *poll_data);
599 void tb_ring_start(struct tb_ring *ring);
600 void tb_ring_stop(struct tb_ring *ring);
601 void tb_ring_free(struct tb_ring *ring);
602 
603 int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
604 
605 /**
606  * tb_ring_rx() - enqueue a frame on an RX ring
607  * @ring: Ring to enqueue the frame
608  * @frame: Frame to enqueue
609  *
610  * @frame->buffer, @frame->buffer_phy have to be set. The buffer must
611  * contain at least %TB_FRAME_SIZE bytes.
612  *
613  * @frame->callback will be invoked with @frame->size, @frame->flags,
614  * @frame->eof, @frame->sof set once the frame has been received.
615  *
616  * If ring_stop() is called after the packet has been enqueued
617  * @frame->callback will be called with canceled set to true.
618  *
619  * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
620  */
tb_ring_rx(struct tb_ring * ring,struct ring_frame * frame)621 static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
622 {
623 	WARN_ON(ring->is_tx);
624 	return __tb_ring_enqueue(ring, frame);
625 }
626 
627 /**
628  * tb_ring_tx() - enqueue a frame on an TX ring
629  * @ring: Ring the enqueue the frame
630  * @frame: Frame to enqueue
631  *
632  * @frame->buffer, @frame->buffer_phy, @frame->size, @frame->eof and
633  * @frame->sof have to be set.
634  *
635  * @frame->callback will be invoked with once the frame has been transmitted.
636  *
637  * If ring_stop() is called after the packet has been enqueued @frame->callback
638  * will be called with canceled set to true.
639  *
640  * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
641  */
tb_ring_tx(struct tb_ring * ring,struct ring_frame * frame)642 static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
643 {
644 	WARN_ON(!ring->is_tx);
645 	return __tb_ring_enqueue(ring, frame);
646 }
647 
648 /* Used only when the ring is in polling mode */
649 struct ring_frame *tb_ring_poll(struct tb_ring *ring);
650 void tb_ring_poll_complete(struct tb_ring *ring);
651 
652 /**
653  * tb_ring_dma_device() - Return device used for DMA mapping
654  * @ring: Ring whose DMA device is retrieved
655  *
656  * Use this function when you are mapping DMA for buffers that are
657  * passed to the ring for sending/receiving.
658  */
tb_ring_dma_device(struct tb_ring * ring)659 static inline struct device *tb_ring_dma_device(struct tb_ring *ring)
660 {
661 	return &ring->nhi->pdev->dev;
662 }
663 
664 #endif /* THUNDERBOLT_H_ */
665