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Diffstat (limited to 'drivers/staging/mei/mei.txt')
| -rw-r--r-- | drivers/staging/mei/mei.txt | 226 |
1 files changed, 126 insertions, 100 deletions
diff --git a/drivers/staging/mei/mei.txt b/drivers/staging/mei/mei.txt index 17302ad2531f..516bfe7319a6 100644 --- a/drivers/staging/mei/mei.txt +++ b/drivers/staging/mei/mei.txt @@ -1,78 +1,74 @@ -Intel MEI +Intel(R) Management Engine Interface (Intel(R) MEI) ======================= Introduction ======================= -The Intel Management Engine (Intel ME) is an isolated and -protected computing resource (Coprocessor) residing inside -Intel chipsets. The Intel ME provides support for computer/IT -management features. -The Feature set depends on the Intel chipset SKU. +The Intel Management Engine (Intel ME) is an isolated andprotected computing +resource (Co-processor) residing inside certain Intel chipsets. The Intel ME +provides support for computer/IT management features. The feature set +depends on the Intel chipset SKU. -The Intel Management Engine Interface (Intel MEI, previously known -as HECI) is the interface between the Host and Intel ME. -This interface is exposed to the host as a PCI device. -The Intel MEI Driver is in charge of the communication channel -between a host application and the ME feature. +The Intel Management Engine Interface (Intel MEI, previously known as HECI) +is the interface between the Host and Intel ME. This interface is exposed +to the host as a PCI device. The Intel MEI Driver is in charge of the +communication channel between a host application and the Intel ME feature. -Each Intel ME feature (Intel ME Client) is addressed by -GUID/UUID and each feature defines its own protocol. -The protocol is message-based with a header and payload up to -512 bytes. +Each Intel ME feature (Intel ME Client) is addressed by a GUID/UUID and +each client has its own protocol. The protocol is message-based with a +header and payload up to 512 bytes. -[place holder to URL to protocol definitions] - -Prominent usage of the Interface is to communicate with -Intel Active Management Technology (Intel AMT) -implemented in firmware running on the Intel ME. +Prominent usage of the Intel ME Interface is to communicate with Intel(R) +Active Management Technology (Intel AMT)implemented in firmware running on +the Intel ME. Intel AMT provides the ability to manage a host remotely out-of-band (OOB) -even when the host processor has crashed or is in a sleep state. +even when the operating system running on the host processor has crashed or +is in a sleep state. Some examples of Intel AMT usage are: - Monitoring hardware state and platform components - - Remote power off/on (useful for green computing or overnight IT maintenance) + - Remote power off/on (useful for green computing or overnight IT + maintenance) - OS updates - Storage of useful platform information such as software assets - - built-in hardware KVM - - selective network isolation of Ethernet and IP protocol flows based on - policies set by a remote management console + - Built-in hardware KVM + - Selective network isolation of Ethernet and IP protocol flows based + on policies set by a remote management console - IDE device redirection from remote management console Intel AMT (OOB) communication is based on SOAP (deprecated -starting with Release 6.0) over HTTP/HTTPS or WS-Management protocol -over HTTP and HTTPS that are received from a remote -management console application. +starting with Release 6.0) over HTTP/S or WS-Management protocol over +HTTP/S that are received from a remote management console application. For more information about Intel AMT: -http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide/WordDocuments/aboutintelamt.htm - +http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide -MEI Driver +Intel MEI Driver ======================= -The driver exposes a character device called /dev/mei. +The driver exposes a misc device called /dev/mei. -An application maintains communication with an ME feature while -/dev/mei is open. The binding to a specific features is performed -by calling MEI_CONNECT_CLIENT_IOCTL, which passes the desired UUID. -The number of instances of an ME feature that can be opened -at the same time depends on the ME feature, but most of the +An application maintains communication with an Intel ME feature while +/dev/mei is open. The binding to a specific features is performed by calling +MEI_CONNECT_CLIENT_IOCTL, which passes the desired UUID. +The number of instances of an Intel ME feature that can be opened +at the same time depends on the Intel ME feature, but most of the features allow only a single instance. - -The Intel AMT Host Interface (AMTHI) feature requires multiple -simultaneous user applications, therefore the MEI driver handles +The Intel AMT Host Interface (Intel AMTHI) feature supports multiple +simultaneous user applications. Therefore, the Intel MEI driver handles this internally by maintaining request queues for the applications. -The driver is oblivious to data that are passed between +The driver is oblivious to data that is passed between firmware feature +and host application. -Because some of the ME features can change the system -configuration, the driver by default allows only privileged +Because some of the Intel ME features can change the system +configuration, the driver by default allows only a privileged user to access it. -A Code snippet for application communicating with AMTHI client: +A code snippet for an application communicating with +Intel AMTHI client: struct mei_connect_client_data data; fd = open(MEI_DEVICE); @@ -80,7 +76,7 @@ A Code snippet for application communicating with AMTHI client: ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &data); - printf(“Ver=%d, MaxLen=%ld\n”, + printf("Ver=%d, MaxLen=%ld\n", data.d.in_client_uuid.protocol_version, data.d.in_client_uuid.max_msg_length); @@ -95,76 +91,106 @@ A Code snippet for application communicating with AMTHI client: [...] close(fd); -ME Applications: +IOCTL: +====== +The Intel MEI Driver supports the following IOCTL command: + IOCTL_MEI_CONNECT_CLIENT Connect to firmware Feature (client). + + usage: + struct mei_connect_client_data clientData; + ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &clientData); + + inputs: + mei_connect_client_data struct contain the following + input field: + + in_client_uuid - UUID of the FW Feature that needs + to connect to. + outputs: + out_client_properties - Client Properties: MTU and Protocol Version. + + error returns: + EINVAL Wrong IOCTL Number + ENODEV Device or Connection is not initialized or ready. + (e.g. Wrong UUID) + ENOMEM Unable to allocate memory to client internal data. + EFAULT Fatal Error (e.g. Unable to access user input data) + EBUSY Connection Already Open + + Notes: + max_msg_length (MTU) in client properties describes the maximum + data that can be sent or received. (e.g. if MTU=2K, can send + requests up to bytes 2k and received responses upto 2k bytes). + +Intel ME Applications: ============== 1) Intel Local Management Service (Intel LMS) - Applications running locally on the platform communicate with - Intel AMT Release 2.0 and later releases in the same way - that network applications do via SOAP over HTTP (deprecated - starting with Release 6.0) or with WS-Management over SOAP over - HTTP. which means that some Intel AMT feature can be access - from a local application using same Network interface as for - remote application. - - When a local application sends a message addressed to the local - Intel AMT host name, the Local Manageability Service (LMS), - which listens for traffic directed to the host name, intercepts - the message and routes it to the Intel Management Engine Interface. + + Applications running locally on the platform communicate with Intel AMT Release + 2.0 and later releases in the same way that network applications do via SOAP + over HTTP (deprecated starting with Release 6.0) or with WS-Management over + SOAP over HTTP. This means that some Intel AMT features can be accessed from a + local application using the same network interface as a remote application + communicating with Intel AMT over the network. + + When a local application sends a message addressed to the local Intel AMT host + name, the Intel LMS, which listens for traffic directed to the host name, + intercepts the message and routes it to the Intel MEI. For more information: - http://software.intel.com/sites/manageability/AMT_Implementation_and_ - Reference_Guide/WordDocuments/localaccess1.htm - - The LMS opens a connection using the MEI driver to the LMS - FW feature using a defined UUID and then communicates with the - feature using a protocol - called Intel(R) AMT Port Forwarding Protocol (APF protocol). - The protocol is used to maintain multiple sessions with - Intel AMT from a single application. - See the protocol specification in - the Intel(R) AMT Implementation and Reference Guide - http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide/HTMLDocuments/MPSDocuments/Intel%20AMT%20Port%20Forwarding%20Protocol%20Reference%20Manual.pdf - - 2) Intel AMT Remote configuration using a Local Agent: + http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide + Under "About Intel AMT" => "Local Access" + + For downloading Intel LMS: + http://software.intel.com/en-us/articles/download-the-latest-intel-amt-open-source-drivers/ + + The Intel LMS opens a connection using the Intel MEI driver to the Intel LMS + firmware feature using a defined UUID and then communicates with the feature + using a protocol called Intel AMT Port Forwarding Protocol(Intel APF protocol). + The protocol is used to maintain multiple sessions with Intel AMT from a + single application. + + See the protocol specification in the Intel AMT Software Development Kit(SDK) + http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide + Under "SDK Resources" => "Intel(R) vPro(TM) Gateway(MPS)" + => "Information for Intel(R) vPro(TM) Gateway Developers" + => "Description of the Intel AMT Port Forwarding (APF)Protocol" + + 2) Intel AMT Remote configuration using a Local Agent A Local Agent enables IT personnel to configure Intel AMT out-of-the-box - without requiring installing additional data to enable setup. - The remote configuration process may involve an ISV-developed remote - configuration agent that runs on the host. + without requiring installing additional data to enable setup. The remote + configuration process may involve an ISV-developed remote configuration + agent that runs on the host. For more information: - http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide/WordDocuments/remoteconfigurationwithalocalagent.htm + http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide + Under "Setup and Configuration of Intel AMT" => + "SDK Tools Supporting Setup and Configuration" => + "Using the Local Agent Sample" + + An open source Intel AMT configuration utility, implementing a local agent + that accesses the Intel MEI driver, can be found here: + http://software.intel.com/en-us/articles/download-the-latest-intel-amt-open-source-drivers/ - How the Local Agent Works (including Command structs): - http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide/WordDocuments/howthelocalagentsampleworks.htm Intel AMT OS Health Watchdog: ============================= The Intel AMT Watchdog is an OS Health (Hang/Crash) watchdog. Whenever the OS hangs or crashes, Intel AMT will send an event -to whoever subscribed to this event. This mechanism means that -IT knows when a platform crashes even when there is a hard failure -on the host. -The AMT Watchdog is composed of two parts: - 1) FW Feature - that receives the heartbeats - and sends an event when the heartbeats stop. - 2) MEI driver – connects to the watchdog (WD) feature, - configures the watchdog and sends the heartbeats. - -The MEI driver configures the Watchdog to expire by default -every 120sec unless set by the user using module parameters. -The Driver then sends heartbeats every 2sec. +to any subsciber to this event. This mechanism means that +IT knows when a platform crashes even when there is a hard failureon the host. -If WD feature does not exist (i.e. the connection failed), -the MEI driver will disable the sending of heartbeats. +The Intel AMT Watchdog is composed of two parts: + 1) Firmware feature - receives the heartbeats + and sends an event when the heartbeats stop. + 2) Intel MEI driver - connects to the watchdog feature, configures the + watchdog and sends the heartbeats. -Module Parameters -================= -watchdog_timeout - the user can use this module parameter -to change the watchdog timeout setting. +The Intel MEI driver uses the kernel watchdog to configure the Intel AMT +Watchdog and to send heartbeats to it. The default timeout of the +watchdog is 120 seconds. -This value sets the Intel AMT watchdog timeout interval in seconds; -the default value is 120sec. -in order to disable the watchdog activites set the value to 0. -Normal values should be between 120 and 65535 +If the Intel AMT Watchdog feature does not exist (i.e. the connection failed), +the Intel MEI driver will disable the sending of heartbeats. Supported Chipsets: ================== |