diff options
author | Tomas Winkler <tomas.winkler@intel.com> | 2012-05-09 16:39:00 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-05-09 13:59:09 -0700 |
commit | 5a44988207ee16b96e5445b8e95ab9881ce310cc (patch) | |
tree | a248b08499d5a96e6f79b622e9bde3292d83809c /Documentation/misc-devices | |
parent | 4f3afe1d8c8e5dc41bb5820c01b4f3cfc2dc1205 (diff) |
mei: move doc files Documentation/misc-devices/mei
1. move mei.txt, TODO, and the example code under Documentation/misc-devices/mei
2. update the TODO file
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/misc-devices')
-rw-r--r-- | Documentation/misc-devices/mei/Makefile | 8 | ||||
-rw-r--r-- | Documentation/misc-devices/mei/TODO | 5 | ||||
-rw-r--r-- | Documentation/misc-devices/mei/mei-amt-version.c | 481 | ||||
-rw-r--r-- | Documentation/misc-devices/mei/mei.txt | 215 |
4 files changed, 709 insertions, 0 deletions
diff --git a/Documentation/misc-devices/mei/Makefile b/Documentation/misc-devices/mei/Makefile new file mode 100644 index 000000000000..00e8c3e836ff --- /dev/null +++ b/Documentation/misc-devices/mei/Makefile @@ -0,0 +1,8 @@ +# kbuild trick to avoid linker error. Can be omitted if a module is built. +obj- := dummy.o + +# List of programs to build +hostprogs-y := mei-amt-version +HOSTCFLAGS_mei-amt-version.o += -I$(objtree)/usr/include +# Tell kbuild to always build the programs +always := $(hostprogs-y) diff --git a/Documentation/misc-devices/mei/TODO b/Documentation/misc-devices/mei/TODO new file mode 100644 index 000000000000..933b2999e19a --- /dev/null +++ b/Documentation/misc-devices/mei/TODO @@ -0,0 +1,5 @@ +TODO: + - Cleanup and split the timer function +Upon Unstaging: + - Documentation/ioctl/ioctl-number.txt + - Updated MAINTAINERS diff --git a/Documentation/misc-devices/mei/mei-amt-version.c b/Documentation/misc-devices/mei/mei-amt-version.c new file mode 100644 index 000000000000..01804f216312 --- /dev/null +++ b/Documentation/misc-devices/mei/mei-amt-version.c @@ -0,0 +1,481 @@ +/****************************************************************************** + * Intel Management Engine Interface (Intel MEI) Linux driver + * Intel MEI Interface Header + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2012 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, + * USA + * + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * Contact Information: + * Intel Corporation. + * linux-mei@linux.intel.com + * http://www.intel.com + * + * BSD LICENSE + * + * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + *****************************************************************************/ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <fcntl.h> +#include <sys/ioctl.h> +#include <unistd.h> +#include <errno.h> +#include <stdint.h> +#include <stdbool.h> +#include <bits/wordsize.h> +#include <linux/mei.h> + +/***************************************************************************** + * Intel Management Engine Interface + *****************************************************************************/ + +#define mei_msg(_me, fmt, ARGS...) do { \ + if (_me->verbose) \ + fprintf(stderr, fmt, ##ARGS); \ +} while (0) + +#define mei_err(_me, fmt, ARGS...) do { \ + fprintf(stderr, "Error: " fmt, ##ARGS); \ +} while (0) + +struct mei { + uuid_le guid; + bool initialized; + bool verbose; + unsigned int buf_size; + unsigned char prot_ver; + int fd; +}; + +static void mei_deinit(struct mei *cl) +{ + if (cl->fd != -1) + close(cl->fd); + cl->fd = -1; + cl->buf_size = 0; + cl->prot_ver = 0; + cl->initialized = false; +} + +static bool mei_init(struct mei *me, const uuid_le *guid, + unsigned char req_protocol_version, bool verbose) +{ + int result; + struct mei_client *cl; + struct mei_connect_client_data data; + + mei_deinit(me); + + me->verbose = verbose; + + me->fd = open("/dev/mei", O_RDWR); + if (me->fd == -1) { + mei_err(me, "Cannot establish a handle to the Intel MEI driver\n"); + goto err; + } + memcpy(&me->guid, guid, sizeof(*guid)); + memset(&data, 0, sizeof(data)); + me->initialized = true; + + memcpy(&data.in_client_uuid, &me->guid, sizeof(me->guid)); + result = ioctl(me->fd, IOCTL_MEI_CONNECT_CLIENT, &data); + if (result) { + mei_err(me, "IOCTL_MEI_CONNECT_CLIENT receive message. err=%d\n", result); + goto err; + } + cl = &data.out_client_properties; + mei_msg(me, "max_message_length %d\n", cl->max_msg_length); + mei_msg(me, "protocol_version %d\n", cl->protocol_version); + + if ((req_protocol_version > 0) && + (cl->protocol_version != req_protocol_version)) { + mei_err(me, "Intel MEI protocol version not supported\n"); + goto err; + } + + me->buf_size = cl->max_msg_length; + me->prot_ver = cl->protocol_version; + + return true; +err: + mei_deinit(me); + return false; +} + +static ssize_t mei_recv_msg(struct mei *me, unsigned char *buffer, + ssize_t len, unsigned long timeout) +{ + ssize_t rc; + + mei_msg(me, "call read length = %zd\n", len); + + rc = read(me->fd, buffer, len); + if (rc < 0) { + mei_err(me, "read failed with status %zd %s\n", + rc, strerror(errno)); + mei_deinit(me); + } else { + mei_msg(me, "read succeeded with result %zd\n", rc); + } + return rc; +} + +static ssize_t mei_send_msg(struct mei *me, const unsigned char *buffer, + ssize_t len, unsigned long timeout) +{ + struct timeval tv; + ssize_t written; + ssize_t rc; + fd_set set; + + tv.tv_sec = timeout / 1000; + tv.tv_usec = (timeout % 1000) * 1000000; + + mei_msg(me, "call write length = %zd\n", len); + + written = write(me->fd, buffer, len); + if (written < 0) { + rc = -errno; + mei_err(me, "write failed with status %zd %s\n", + written, strerror(errno)); + goto out; + } + + FD_ZERO(&set); + FD_SET(me->fd, &set); + rc = select(me->fd + 1 , &set, NULL, NULL, &tv); + if (rc > 0 && FD_ISSET(me->fd, &set)) { + mei_msg(me, "write success\n"); + } else if (rc == 0) { + mei_err(me, "write failed on timeout with status\n"); + goto out; + } else { /* rc < 0 */ + mei_err(me, "write failed on select with status %zd\n", rc); + goto out; + } + + rc = written; +out: + if (rc < 0) + mei_deinit(me); + + return rc; +} + +/*************************************************************************** + * Intel Advanced Management Technolgy ME Client + ***************************************************************************/ + +#define AMT_MAJOR_VERSION 1 +#define AMT_MINOR_VERSION 1 + +#define AMT_STATUS_SUCCESS 0x0 +#define AMT_STATUS_INTERNAL_ERROR 0x1 +#define AMT_STATUS_NOT_READY 0x2 +#define AMT_STATUS_INVALID_AMT_MODE 0x3 +#define AMT_STATUS_INVALID_MESSAGE_LENGTH 0x4 + +#define AMT_STATUS_HOST_IF_EMPTY_RESPONSE 0x4000 +#define AMT_STATUS_SDK_RESOURCES 0x1004 + + +#define AMT_BIOS_VERSION_LEN 65 +#define AMT_VERSIONS_NUMBER 50 +#define AMT_UNICODE_STRING_LEN 20 + +struct amt_unicode_string { + uint16_t length; + char string[AMT_UNICODE_STRING_LEN]; +} __attribute__((packed)); + +struct amt_version_type { + struct amt_unicode_string description; + struct amt_unicode_string version; +} __attribute__((packed)); + +struct amt_version { + uint8_t major; + uint8_t minor; +} __attribute__((packed)); + +struct amt_code_versions { + uint8_t bios[AMT_BIOS_VERSION_LEN]; + uint32_t count; + struct amt_version_type versions[AMT_VERSIONS_NUMBER]; +} __attribute__((packed)); + +/*************************************************************************** + * Intel Advanced Management Technolgy Host Interface + ***************************************************************************/ + +struct amt_host_if_msg_header { + struct amt_version version; + uint16_t _reserved; + uint32_t command; + uint32_t length; +} __attribute__((packed)); + +struct amt_host_if_resp_header { + struct amt_host_if_msg_header header; + uint32_t status; + unsigned char data[0]; +} __attribute__((packed)); + +const uuid_le MEI_IAMTHIF = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, \ + 0xac, 0xa8, 0x46, 0xe0, 0xff, 0x65, 0x81, 0x4c); + +#define AMT_HOST_IF_CODE_VERSIONS_REQUEST 0x0400001A +#define AMT_HOST_IF_CODE_VERSIONS_RESPONSE 0x0480001A + +const struct amt_host_if_msg_header CODE_VERSION_REQ = { + .version = {AMT_MAJOR_VERSION, AMT_MINOR_VERSION}, + ._reserved = 0, + .command = AMT_HOST_IF_CODE_VERSIONS_REQUEST, + .length = 0 +}; + + +struct amt_host_if { + struct mei mei_cl; + unsigned long send_timeout; + bool initialized; +}; + + +static bool amt_host_if_init(struct amt_host_if *acmd, + unsigned long send_timeout, bool verbose) +{ + acmd->send_timeout = (send_timeout) ? send_timeout : 20000; + acmd->initialized = mei_init(&acmd->mei_cl, &MEI_IAMTHIF, 0, verbose); + return acmd->initialized; +} + +static void amt_host_if_deinit(struct amt_host_if *acmd) +{ + mei_deinit(&acmd->mei_cl); + acmd->initialized = false; +} + +static uint32_t amt_verify_code_versions(const struct amt_host_if_resp_header *resp) +{ + uint32_t status = AMT_STATUS_SUCCESS; + struct amt_code_versions *code_ver; + size_t code_ver_len; + uint32_t ver_type_cnt; + uint32_t len; + uint32_t i; + + code_ver = (struct amt_code_versions *)resp->data; + /* length - sizeof(status) */ + code_ver_len = resp->header.length - sizeof(uint32_t); + ver_type_cnt = code_ver_len - + sizeof(code_ver->bios) - + sizeof(code_ver->count); + if (code_ver->count != ver_type_cnt / sizeof(struct amt_version_type)) { + status = AMT_STATUS_INTERNAL_ERROR; + goto out; + } + + for (i = 0; i < code_ver->count; i++) { + len = code_ver->versions[i].description.length; + + if (len > AMT_UNICODE_STRING_LEN) { + status = AMT_STATUS_INTERNAL_ERROR; + goto out; + } + + len = code_ver->versions[i].version.length; + if (code_ver->versions[i].version.string[len] != '\0' || + len != strlen(code_ver->versions[i].version.string)) { + status = AMT_STATUS_INTERNAL_ERROR; + goto out; + } + } +out: + return status; +} + +static uint32_t amt_verify_response_header(uint32_t command, + const struct amt_host_if_msg_header *resp_hdr, + uint32_t response_size) +{ + if (response_size < sizeof(struct amt_host_if_resp_header)) { + return AMT_STATUS_INTERNAL_ERROR; + } else if (response_size != (resp_hdr->length + + sizeof(struct amt_host_if_msg_header))) { + return AMT_STATUS_INTERNAL_ERROR; + } else if (resp_hdr->command != command) { + return AMT_STATUS_INTERNAL_ERROR; + } else if (resp_hdr->_reserved != 0) { + return AMT_STATUS_INTERNAL_ERROR; + } else if (resp_hdr->version.major != AMT_MAJOR_VERSION || + resp_hdr->version.minor < AMT_MINOR_VERSION) { + return AMT_STATUS_INTERNAL_ERROR; + } + return AMT_STATUS_SUCCESS; +} + +static uint32_t amt_host_if_call(struct amt_host_if *acmd, + const unsigned char *command, ssize_t command_sz, + uint8_t **read_buf, uint32_t rcmd, + unsigned int expected_sz) +{ + uint32_t in_buf_sz; + uint32_t out_buf_sz; + ssize_t written; + uint32_t status; + struct amt_host_if_resp_header *msg_hdr; + + in_buf_sz = acmd->mei_cl.buf_size; + *read_buf = (uint8_t *)malloc(sizeof(uint8_t) * in_buf_sz); + if (*read_buf == NULL) + return AMT_STATUS_SDK_RESOURCES; + memset(*read_buf, 0, in_buf_sz); + msg_hdr = (struct amt_host_if_resp_header *)*read_buf; + + written = mei_send_msg(&acmd->mei_cl, + command, command_sz, acmd->send_timeout); + if (written != command_sz) + return AMT_STATUS_INTERNAL_ERROR; + + out_buf_sz = mei_recv_msg(&acmd->mei_cl, *read_buf, in_buf_sz, 2000); + if (out_buf_sz <= 0) + return AMT_STATUS_HOST_IF_EMPTY_RESPONSE; + + status = msg_hdr->status; + if (status != AMT_STATUS_SUCCESS) + return status; + + status = amt_verify_response_header(rcmd, + &msg_hdr->header, out_buf_sz); + if (status != AMT_STATUS_SUCCESS) + return status; + + if (expected_sz && expected_sz != out_buf_sz) + return AMT_STATUS_INTERNAL_ERROR; + + return AMT_STATUS_SUCCESS; +} + + +static uint32_t amt_get_code_versions(struct amt_host_if *cmd, + struct amt_code_versions *versions) +{ + struct amt_host_if_resp_header *response = NULL; + uint32_t status; + + status = amt_host_if_call(cmd, + (const unsigned char *)&CODE_VERSION_REQ, + sizeof(CODE_VERSION_REQ), + (uint8_t **)&response, + AMT_HOST_IF_CODE_VERSIONS_RESPONSE, 0); + + if (status != AMT_STATUS_SUCCESS) + goto out; + + status = amt_verify_code_versions(response); + if (status != AMT_STATUS_SUCCESS) + goto out; + + memcpy(versions, response->data, sizeof(struct amt_code_versions)); +out: + if (response != NULL) + free(response); + + return status; +} + +/************************** end of amt_host_if_command ***********************/ +int main(int argc, char **argv) +{ + struct amt_code_versions ver; + struct amt_host_if acmd; + unsigned int i; + uint32_t status; + int ret; + bool verbose; + + verbose = (argc > 1 && strcmp(argv[1], "-v") == 0); + + if (!amt_host_if_init(&acmd, 5000, verbose)) { + ret = 1; + goto out; + } + + status = amt_get_code_versions(&acmd, &ver); + + amt_host_if_deinit(&acmd); + + switch (status) { + case AMT_STATUS_HOST_IF_EMPTY_RESPONSE: + printf("Intel AMT: DISABLED\n"); + ret = 0; + break; + case AMT_STATUS_SUCCESS: + printf("Intel AMT: ENABLED\n"); + for (i = 0; i < ver.count; i++) { + printf("%s:\t%s\n", ver.versions[i].description.string, + ver.versions[i].version.string); + } + ret = 0; + break; + default: + printf("An error has occurred\n"); + ret = 1; + break; + } + +out: + return ret; +} diff --git a/Documentation/misc-devices/mei/mei.txt b/Documentation/misc-devices/mei/mei.txt new file mode 100644 index 000000000000..2785697da59d --- /dev/null +++ b/Documentation/misc-devices/mei/mei.txt @@ -0,0 +1,215 @@ +Intel(R) Management Engine Interface (Intel(R) MEI) +======================= + +Introduction +======================= + +The Intel Management Engine (Intel ME) is an isolated and protected 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 Intel ME feature. + +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. + +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 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) + - 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 + - IDE device redirection from remote management console + +Intel AMT (OOB) communication is based on SOAP (deprecated +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 + +Intel MEI Driver +======================= + +The driver exposes a misc device called /dev/mei. + +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 (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 is passed between firmware feature +and host application. + +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 an application communicating with +Intel AMTHI client: + struct mei_connect_client_data data; + fd = open(MEI_DEVICE); + + data.d.in_client_uuid = AMTHI_UUID; + + ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &data); + + printf("Ver=%d, MaxLen=%ld\n", + data.d.in_client_uuid.protocol_version, + data.d.in_client_uuid.max_msg_length); + + [...] + + write(fd, amthi_req_data, amthi_req_data_len); + + [...] + + read(fd, &amthi_res_data, amthi_res_data_len); + + [...] + close(fd); + +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. 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 + 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. + For more information: + 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/ + + +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 any subscriber to this event. This mechanism means that +IT knows when a platform crashes even when there is a hard failure on the host. + +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. + +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. + +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: +================== +7 Series Chipset Family +6 Series Chipset Family +5 Series Chipset Family +4 Series Chipset Family +Mobile 4 Series Chipset Family +ICH9 +82946GZ/GL +82G35 Express +82Q963/Q965 +82P965/G965 +Mobile PM965/GM965 +Mobile GME965/GLE960 +82Q35 Express +82G33/G31/P35/P31 Express +82Q33 Express +82X38/X48 Express + +--- +linux-mei@linux.intel.com |