mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 12:28:41 +08:00
mei: docs: update mei documentation
The mei driver went via multiple changes, update the documentation and fix formatting. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tomas Winkler
Greg Kroah-Hartman
parent
0e3743d870
commit
d0a178095c
@ -5,34 +5,32 @@ 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.
|
||||
provides support for computer/IT management and security features.
|
||||
The actual 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.
|
||||
to the host as a PCI device, actually multiple PCI devices might be exposed.
|
||||
The Intel MEI Driver is in charge of the communication channel between
|
||||
a host application and the Intel ME features.
|
||||
|
||||
Each Intel ME feature (Intel ME Client) is addressed by a GUID/UUID and
|
||||
Each Intel ME feature, or Intel ME Client is addressed by a unique GUID and
|
||||
each client has its own protocol. The protocol is message-based with a
|
||||
header and payload up to 512 bytes.
|
||||
header and payload up to maximal number of bytes advertised by the client,
|
||||
upon connection.
|
||||
|
||||
Intel MEI Driver
|
||||
================
|
||||
|
||||
The driver exposes a misc device called /dev/mei.
|
||||
The driver exposes a character device with device nodes /dev/meiX.
|
||||
|
||||
An application maintains communication with an Intel ME feature while
|
||||
/dev/mei is open. The binding to a specific feature is performed by calling
|
||||
MEI_CONNECT_CLIENT_IOCTL, which passes the desired UUID.
|
||||
/dev/meiX is open. The binding to a specific feature is performed by calling
|
||||
:c:macro:`MEI_CONNECT_CLIENT_IOCTL`, which passes the desired GUID.
|
||||
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 connected applications. The Intel MEI driver
|
||||
handles this internally by maintaining request queues for the applications.
|
||||
|
||||
The driver is transparent to data that are passed between firmware feature
|
||||
and host application.
|
||||
|
||||
@ -40,6 +38,8 @@ Because some of the Intel ME features can change the system
|
||||
configuration, the driver by default allows only a privileged
|
||||
user to access it.
|
||||
|
||||
The session is terminated calling :c:func:`close(int fd)`.
|
||||
|
||||
A code snippet for an application communicating with Intel AMTHI client:
|
||||
|
||||
.. code-block:: C
|
||||
@ -47,13 +47,13 @@ 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;
|
||||
data.d.in_client_uuid = AMTHI_GUID;
|
||||
|
||||
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);
|
||||
data.d.in_client_uuid.protocol_version,
|
||||
data.d.in_client_uuid.max_msg_length);
|
||||
|
||||
[...]
|
||||
|
||||
@ -67,60 +67,86 @@ A code snippet for an application communicating with Intel AMTHI client:
|
||||
close(fd);
|
||||
|
||||
|
||||
IOCTLs
|
||||
======
|
||||
User space API
|
||||
|
||||
IOCTLs:
|
||||
=======
|
||||
|
||||
The Intel MEI Driver supports the following IOCTL commands:
|
||||
IOCTL_MEI_CONNECT_CLIENT Connect to firmware Feature (client).
|
||||
|
||||
usage:
|
||||
struct mei_connect_client_data clientData;
|
||||
ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &clientData);
|
||||
IOCTL_MEI_CONNECT_CLIENT
|
||||
-------------------------
|
||||
Connect to firmware Feature/Client.
|
||||
|
||||
inputs:
|
||||
mei_connect_client_data struct contain the following
|
||||
input field:
|
||||
.. code-block:: none
|
||||
|
||||
in_client_uuid - UUID of the FW Feature that needs
|
||||
Usage:
|
||||
|
||||
struct mei_connect_client_data client_data;
|
||||
|
||||
ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &client_data);
|
||||
|
||||
Inputs:
|
||||
|
||||
struct mei_connect_client_data - contain the following
|
||||
Input field:
|
||||
|
||||
in_client_uuid - GUID of the FW Feature that needs
|
||||
to connect to.
|
||||
outputs:
|
||||
Outputs:
|
||||
out_client_properties - Client Properties: MTU and Protocol Version.
|
||||
|
||||
error returns:
|
||||
Error returns:
|
||||
|
||||
ENOTTY No such client (i.e. wrong GUID) or connection is not allowed.
|
||||
EINVAL Wrong IOCTL Number
|
||||
ENODEV Device or Connection is not initialized or ready. (e.g. Wrong UUID)
|
||||
ENODEV Device or Connection is not initialized or ready.
|
||||
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:
|
||||
:Note:
|
||||
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 up to 2k bytes).
|
||||
|
||||
IOCTL_MEI_NOTIFY_SET: enable or disable event notifications
|
||||
|
||||
IOCTL_MEI_NOTIFY_SET
|
||||
---------------------
|
||||
Enable or disable event notifications.
|
||||
|
||||
|
||||
.. code-block:: none
|
||||
|
||||
Usage:
|
||||
|
||||
uint32_t enable;
|
||||
|
||||
ioctl(fd, IOCTL_MEI_NOTIFY_SET, &enable);
|
||||
|
||||
Inputs:
|
||||
|
||||
uint32_t enable = 1;
|
||||
or
|
||||
uint32_t enable[disable] = 0;
|
||||
|
||||
Error returns:
|
||||
|
||||
|
||||
EINVAL Wrong IOCTL Number
|
||||
ENODEV Device is not initialized or the client not connected
|
||||
ENOMEM Unable to allocate memory to client internal data.
|
||||
EFAULT Fatal Error (e.g. Unable to access user input data)
|
||||
EOPNOTSUPP if the device doesn't support the feature
|
||||
|
||||
Notes:
|
||||
:Note:
|
||||
The client must be connected in order to enable notification events
|
||||
|
||||
|
||||
IOCTL_MEI_NOTIFY_GET : retrieve event
|
||||
IOCTL_MEI_NOTIFY_GET
|
||||
--------------------
|
||||
Retrieve event
|
||||
|
||||
.. code-block:: none
|
||||
|
||||
Usage:
|
||||
uint32_t event;
|
||||
@ -137,7 +163,7 @@ The Intel MEI Driver supports the following IOCTL commands:
|
||||
EFAULT Fatal Error (e.g. Unable to access user input data)
|
||||
EOPNOTSUPP if the device doesn't support the feature
|
||||
|
||||
Notes:
|
||||
:Note:
|
||||
The client must be connected and event notification has to be enabled
|
||||
in order to receive an event
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user