1 What: /sys/bus/thunderbolt/devices/.../domainX/boot_acl
4 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
5 Description: Holds a comma separated list of device unique_ids that
6 are allowed to be connected automatically during system
7 startup (e.g boot devices). The list always contains
8 maximum supported number of unique_ids where unused
9 entries are empty. This allows the userspace software
10 to determine how many entries the controller supports.
11 If there are multiple controllers, each controller has
12 its own ACL list and size may be different between the
15 System BIOS may have an option "Preboot ACL" or similar
16 that needs to be selected before this list is taken into
19 Software always updates a full list in each write.
21 If a device is authorized automatically during boot its
22 boot attribute is set to 1.
24 What: /sys/bus/thunderbolt/devices/.../domainX/deauthorization
27 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
28 Description: This attribute tells whether the system supports
29 de-authorization of devices. Value of 1 means user can
30 de-authorize PCIe tunnel by writing 0 to authorized
31 attribute under each device.
33 What: /sys/bus/thunderbolt/devices/.../domainX/iommu_dma_protection
36 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
37 Description: This attribute tells whether the system uses IOMMU
38 for DMA protection. Value of 1 means IOMMU is used 0 means
39 it is not (DMA protection is solely based on Thunderbolt
42 What: /sys/bus/thunderbolt/devices/.../domainX/security
45 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
46 Description: This attribute holds current Thunderbolt security level
47 set by the system BIOS. Possible values are:
49 ======= ==================================================
50 none All devices are automatically authorized
51 user Devices are only authorized based on writing
52 appropriate value to the authorized attribute
53 secure Require devices that support secure connect at
54 minimum. User needs to authorize each device.
55 dponly Automatically tunnel Display port (and USB). No
56 PCIe tunnels are created.
57 usbonly Automatically tunnel USB controller of the
58 connected Thunderbolt dock (and Display Port). All
59 PCIe links downstream of the dock are removed.
60 nopcie USB4 system where PCIe tunneling is disabled from
62 ======= ==================================================
64 What: /sys/bus/thunderbolt/devices/.../authorized
67 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
68 Description: This attribute is used to authorize Thunderbolt devices
69 after they have been connected. If the device is not
70 authorized, no PCIe devices are available to the system.
72 Contents of this attribute will be 0 when the device is not
75 Possible values are supported:
77 == ===================================================
78 0 The device will be de-authorized (only supported if
79 deauthorization attribute under domain contains 1)
80 1 The device will be authorized and connected
81 == ===================================================
83 When key attribute contains 32 byte hex string the possible
86 == ========================================================
87 0 The device will be de-authorized (only supported if
88 deauthorization attribute under domain contains 1)
89 1 The 32 byte hex string is added to the device NVM and
90 the device is authorized.
91 2 Send a challenge based on the 32 byte hex string. If the
92 challenge response from device is valid, the device is
93 authorized. In case of failure errno will be ENOKEY if
94 the device did not contain a key at all, and
95 EKEYREJECTED if the challenge response did not match.
96 == ========================================================
98 What: /sys/bus/thunderbolt/devices/.../boot
101 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
102 Description: This attribute contains 1 if Thunderbolt device was already
103 authorized on boot and 0 otherwise.
105 What: /sys/bus/thunderbolt/devices/.../generation
108 Contact: Christian Kellner <christian@kellner.me>
109 Description: This attribute contains the generation of the Thunderbolt
110 controller associated with the device. It will contain 4
113 What: /sys/bus/thunderbolt/devices/.../key
116 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
117 Description: When a devices supports Thunderbolt secure connect it will
118 have this attribute. Writing 32 byte hex string changes
119 authorization to use the secure connection method instead.
120 Writing an empty string clears the key and regular connection
121 method can be used again.
123 What: /sys/bus/thunderbolt/devices/.../device
126 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
127 Description: This attribute contains id of this device extracted from
130 What: /sys/bus/thunderbolt/devices/.../device_name
133 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
134 Description: This attribute contains name of this device extracted from
137 What: /sys/bus/thunderbolt/devices/.../maxhopid
140 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
141 Description: Only set for XDomains. The maximum HopID the other host
142 supports as its input HopID.
144 What: /sys/bus/thunderbolt/devices/.../rx_speed
147 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
148 Description: This attribute reports the device RX speed per lane.
149 All RX lanes run at the same speed.
151 What: /sys/bus/thunderbolt/devices/.../rx_lanes
154 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
155 Description: This attribute reports number of RX lanes the device is
156 using simultaneously through its upstream port.
158 What: /sys/bus/thunderbolt/devices/.../tx_speed
161 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
162 Description: This attribute reports the TX speed per lane.
163 All TX lanes run at the same speed.
165 What: /sys/bus/thunderbolt/devices/.../tx_lanes
168 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
169 Description: This attribute reports number of TX lanes the device is
170 using simultaneously through its upstream port.
172 What: /sys/bus/thunderbolt/devices/.../vendor
175 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
176 Description: This attribute contains vendor id of this device extracted
177 from the device DROM.
179 What: /sys/bus/thunderbolt/devices/.../vendor_name
182 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
183 Description: This attribute contains vendor name of this device extracted
184 from the device DROM.
186 What: /sys/bus/thunderbolt/devices/.../unique_id
189 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
190 Description: This attribute contains unique_id string of this device.
191 This is either read from hardware registers (UUID on
192 newer hardware) or based on UID from the device DROM.
193 Can be used to uniquely identify particular device.
195 What: /sys/bus/thunderbolt/devices/.../nvm_version
198 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
199 Description: If the device has upgradeable firmware the version
200 number is available here. Format: %x.%x, major.minor.
201 If the device is in safe mode reading the file returns
202 -ENODATA instead as the NVM version is not available.
204 What: /sys/bus/thunderbolt/devices/.../nvm_authenticate
207 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
208 Description: When new NVM image is written to the non-active NVM
209 area (through non_activeX NVMem device), the
210 authentication procedure is started by writing to
212 If everything goes well, the device is
213 restarted with the new NVM firmware. If the image
214 verification fails an error code is returned instead.
216 This file will accept writing values "1", "2" or "3".
218 - Writing "1" will flush the image to the storage
219 area and authenticate the image in one action.
220 - Writing "2" will run some basic validation on the image
221 and flush it to the storage area.
222 - Writing "3" will authenticate the image that is
223 currently written in the storage area. This is only
224 supported with USB4 devices and retimers.
226 When read holds status of the last authentication
227 operation if an error occurred during the process. This
228 is directly the status value from the DMA configuration
229 based mailbox before the device is power cycled. Writing
230 0 here clears the status.
232 What: /sys/bus/thunderbolt/devices/.../nvm_authenticate_on_disconnect
235 Contact: Mario Limonciello <mario.limonciello@outlook.com>
236 Description: For supported devices, automatically authenticate the new Thunderbolt
237 image when the device is disconnected from the host system.
239 This file will accept writing values "1" or "2"
241 - Writing "1" will flush the image to the storage
242 area and prepare the device for authentication on disconnect.
243 - Writing "2" will run some basic validation on the image
244 and flush it to the storage area.
246 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/key
249 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
250 Description: This contains name of the property directory the XDomain
251 service exposes. This entry describes the protocol in
252 question. Following directories are already reserved by
253 the Apple XDomain specification:
255 ======== ===============================================
256 network IP/ethernet over Thunderbolt
257 targetdm Target disk mode protocol over Thunderbolt
258 extdisp External display mode protocol over Thunderbolt
259 ======== ===============================================
261 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/modalias
264 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
265 Description: Stores the same MODALIAS value emitted by uevent for
266 the XDomain service. Format: tbtsvc:kSpNvNrN
268 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcid
271 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
272 Description: This contains XDomain protocol identifier the XDomain
275 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcvers
278 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
279 Description: This contains XDomain protocol version the XDomain
282 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcrevs
285 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
286 Description: This contains XDomain software version the XDomain
289 What: /sys/bus/thunderbolt/devices/<xdomain>.<service>/prtcstns
292 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
293 Description: This contains XDomain service specific settings as
296 What: /sys/bus/thunderbolt/devices/usb4_portX/connector
298 Contact: Heikki Krogerus <heikki.krogerus@linux.intel.com>
300 Symlink to the USB Type-C connector. This link is only
301 created when USB Type-C Connector Class is enabled,
302 and only if the system firmware is capable of
303 describing the connection between a port and its
306 What: /sys/bus/thunderbolt/devices/usb4_portX/link
309 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
310 Description: Returns the current link mode. Possible values are
311 "usb4", "tbt" and "none".
313 What: /sys/bus/thunderbolt/devices/usb4_portX/offline
316 Contact: Rajmohan Mani <rajmohan.mani@intel.com>
317 Description: Writing 1 to this attribute puts the USB4 port into
318 offline mode. Only allowed when there is nothing
319 connected to the port (link attribute returns "none").
320 Once the port is in offline mode it does not receive any
321 hotplug events. This is used to update NVM firmware of
322 on-board retimers. Writing 0 puts the port back to
325 This attribute is only visible if the platform supports
326 powering on retimers when there is no cable connected.
328 What: /sys/bus/thunderbolt/devices/usb4_portX/rescan
331 Contact: Rajmohan Mani <rajmohan.mani@intel.com>
332 Description: When the USB4 port is in offline mode writing 1 to this
333 attribute forces rescan of the sideband for on-board
334 retimers. Each retimer appear under the USB4 port as if
335 the USB4 link was up. These retimers act in the same way
336 as if the cable was connected so upgrading their NVM
337 firmware can be done the usual way.
339 What: /sys/bus/thunderbolt/devices/<device>:<port>.<index>/device
342 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
343 Description: Retimer device identifier read from the hardware.
345 What: /sys/bus/thunderbolt/devices/<device>:<port>.<index>/nvm_authenticate
348 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
349 Description: When new NVM image is written to the non-active NVM
350 area (through non_activeX NVMem device), the
351 authentication procedure is started by writing 1 to
352 this file. If everything goes well, the device is
353 restarted with the new NVM firmware. If the image
354 verification fails an error code is returned instead.
356 When read holds status of the last authentication
357 operation if an error occurred during the process.
360 What: /sys/bus/thunderbolt/devices/<device>:<port>.<index>/nvm_version
363 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
364 Description: Holds retimer NVM version number. Format: %x.%x, major.minor.
366 What: /sys/bus/thunderbolt/devices/<device>:<port>.<index>/vendor
369 Contact: Mika Westerberg <mika.westerberg@linux.intel.com>
370 Description: Retimer vendor identifier read from the hardware.