Adding Thunderbolt(TM) networking documentation. Signed-off-by: Amir Levy <amir.jer.levy@xxxxxxxxx> --- Documentation/00-INDEX | 2 + Documentation/thunderbolt/networking.txt | 132 +++++++++++++++++++++++++++++++ 2 files changed, 134 insertions(+) create mode 100644 Documentation/thunderbolt/networking.txt diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index 3acc4f1..0239e68 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -440,6 +440,8 @@ this_cpu_ops.txt - List rationale behind and the way to use this_cpu operations. thermal/ - directory with information on managing thermal issues (CPU/temp) +thunderbolt/ + - directory with info regarding Thunderbolt. trace/ - directory with info on tracing technologies within linux unaligned-memory-access.txt diff --git a/Documentation/thunderbolt/networking.txt b/Documentation/thunderbolt/networking.txt new file mode 100644 index 0000000..88d1c12 --- /dev/null +++ b/Documentation/thunderbolt/networking.txt @@ -0,0 +1,132 @@ +Intel Thunderbolt(TM) Networking driver +======================================= + +Copyright(c) 2013 - 2016 Intel Corporation. + +Contact Information: +Intel Thunderbolt mailing list <thunderbolt-software@xxxxxxxxxxxx> +Edited by Amir Levy <amir.jer.levy@xxxxxxxxx> + +Overview +======== + +* The Thunderbolt Networking driver enables peer to peer networking on non-Apple + platforms running Linux. + +* The driver creates a virtual Ethernet device that enables computer to computer + communication over the Thunderbolt cable. + +* Using Thunderbolt Networking you can perform high speed file transfers between + computers, perform PC migrations and/or set up small workgroups with shared + storage without compromising any other Thunderbolt functionality. + +* The driver is located in drivers/thunderbolt/icm. + +* This driver will function only on non-Apple platforms with firmware based + Thunderbolt controllers that support Thunderbolt Networking. + + +----------------+ +----------------+ + |Host 1 | |Host 2 | + | | | | + | +-------+ | | +-------+ | + | |Network| | | |Network| | + | |Stack | | | |Stack | | + | +-------+ | | +-------+ | + | ^ | | ^ | + | | | | | | + | v | | v | + | +-----------+ | | +-----------+ | + | |Thunderbolt| | | |Thunderbolt| | + | |Networking | | | |Networking | | + | |Driver | | | |Driver | | + | +-----------+ | | +-----------+ | + | ^ | | ^ | + | | | | | | + | v | | v | + | +-----------+ | | +-----------+ | + | |Thunderbolt| | | |Thunderbolt| | + | |Controller |<-+------------+->|Controller | | + | |with ICM | | | |with ICM | | + | |enabled | | | |enabled | | + | +-----------+ | | +-----------+ | + +----------------+ +----------------+ + +Files +===== + +The following files are located in the drivers/thunderbolt/icm directory: + +- icm_nhi.c/h: These files allow communication with the firmware (Intel + Connection Manager) based controller. They also create an interface for + netlink communication with a user space daemon. + +- net.c/net.h: These files implement the 'eth' interface for the + Thunderbolt(TM) Networking. + +Interface to User Space +======================= + +The interface to the user space module is implemented through a Generic Netlink. +This is the communications protocol between the Thunderbolt driver and the user +space application. + +Note that this interface mediates user space communication with ICM. +(Existing Linux tools can be used to configure the network interface.) + +The Thunderbolt Daemon utilizes this interface to communicate with the driver. +To be accessed by the user space module, both kernel and user space modules +have to register with the same GENL_NAME. +For the purpose of the Thunderbolt Network driver, "thunderbolt" is used. +The registration is done at driver initialization time for all instances +of the Thunderbolt controllers. The communication is carried through pre-defined +Thunderbolt messages. Each specific message has a callback function that is +called when the related message is received. + +Message Definitions: +* NHI_CMD_UNSPEC: Not used. +* NHI_CMD_SUBSCRIBE: Subscription request from daemon to driver to open the + communication channel. +* NHI_CMD_UNSUBSCRIBE: Request from daemon to driver to unsubscribe and + to close communication channel. +* NHI_CMD_QUERY_INFORMATION: Request information from the driver such as + driver version, FW version offset, number of ports in the controller + and DMA port. +* NHI_CMD_MSG_TO_ICM: Message from user space module to FW. +* NHI_CMD_MSG_FROM_ICM: Response from FW to user space module. +* NHI_CMD_MAILBOX: Message that uses mailbox mechanism such as FW policy + changes or disconnect path. +* NHI_CMD_APPROVE_TBT_NETWORKING: Request from user space module to FW to + establish path. +* NHI_CMD_ICM_IN_SAFE_MODE: Indication that the FW has entered safe mode. + +Communication with Intel Connection Manager(ICM) Firmware +========================================================= + +There are several circular buffers in Thunderbolt each using Direct Memory +Access (DMA). + +Communication with ICM utilizes circular buffer ring #0. (The other rings are +used for peer to peer communication, packet transmission and receiving). + +The driver allocates a shared memory that is physically mapped onto the DMA +physical space at ring #0. +For the software to communicate with the firmware, the driver sends a command +in ring #0. The command contains a pre-defined field (PDF) value notifying the +firmware that the driver is ready. To proceed, the driver must receive the +appropriate PDF value in response from the firmware. + +Once the exchange is completed, messages can be sent to the firmware through +the driver. Similarly, the firmware can now send notifications about hardware +and firmware events. + +Information +=========== + +Mailing list: + thunderbolt-software@xxxxxxxxxxxx + Register at: https://lists.01.org/mailman/listinfo/thunderbolt-software + Archives at: https://lists.01.org/pipermail/thunderbolt-software/ + +For additional information about Thunderbolt technology visit: + https://01.org/thunderbolt-sw + https://thunderbolttechnology.net/ -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
