diff options
Diffstat (limited to 'Documentation/driver-api/ipmi.rst')
| -rw-r--r-- | Documentation/driver-api/ipmi.rst | 64 |
1 files changed, 62 insertions, 2 deletions
diff --git a/Documentation/driver-api/ipmi.rst b/Documentation/driver-api/ipmi.rst index bc281f10ce4b..e224e47b6b09 100644 --- a/Documentation/driver-api/ipmi.rst +++ b/Documentation/driver-api/ipmi.rst @@ -166,8 +166,8 @@ and the type is IPMI_SYSTEM_INTERFACE_ADDR_TYPE. This is used for talking straight to the BMC on the current card. The channel must be IPMI_BMC_CHANNEL. -Messages that are destined to go out on the IPMB bus use the -IPMI_IPMB_ADDR_TYPE address type. The format is:: +Messages that are destined to go out on the IPMB bus going through the +BMC use the IPMI_IPMB_ADDR_TYPE address type. The format is:: struct ipmi_ipmb_addr { @@ -181,6 +181,23 @@ The "channel" here is generally zero, but some devices support more than one channel, it corresponds to the channel as defined in the IPMI spec. +There is also an IPMB direct address for a situation where the sender +is directly on an IPMB bus and doesn't have to go through the BMC. +You can send messages to a specific management controller (MC) on the +IPMB using the IPMI_IPMB_DIRECT_ADDR_TYPE with the following format:: + + struct ipmi_ipmb_direct_addr + { + int addr_type; + short channel; + unsigned char slave_addr; + unsigned char rq_lun; + unsigned char rs_lun; + }; + +The channel is always zero. You can also receive commands from other +MCs that you have registered to handle and respond to them, so you can +use this to implement a management controller on a bus.. Messages -------- @@ -348,6 +365,10 @@ user may be registered for each netfn/cmd/channel, but different users may register for different commands, or the same command if the channel bitmasks do not overlap. +To respond to a received command, set the response bit in the returned +netfn, use the address from the received message, and use the same +msgid that you got in the receive message. + From userland, equivalent IOCTLs are provided to do these functions. @@ -570,6 +591,45 @@ web page. The driver supports a hot add and remove of interfaces through the I2C sysfs interface. +The IPMI IPMB Driver +-------------------- + +This driver is for supporting a system that sits on an IPMB bus; it +allows the interface to look like a normal IPMI interface. Sending +system interface addressed messages to it will cause the message to go +to the registered BMC on the system (default at IPMI address 0x20). + +It also allows you to directly address other MCs on the bus using the +ipmb direct addressing. You can receive commands from other MCs on +the bus and they will be handled through the normal received command +mechanism described above. + +Parameters are:: + + ipmi_ipmb.bmcaddr=<address to use for system interface addresses messages> + ipmi_ipmb.retry_time_ms=<Time between retries on IPMB> + ipmi_ipmb.max_retries=<Number of times to retry a message> + +Loading the module will not result in the driver automatcially +starting unless there is device tree information setting it up. If +you want to instantiate one of these by hand, do:: + + echo ipmi-ipmb <addr> > /sys/class/i2c-dev/i2c-<n>/device/new_device + +Note that the address you give here is the I2C address, not the IPMI +address. So if you want your MC address to be 0x60, you put 0x30 +here. See the I2C driver info for more details. + +Command bridging to other IPMB busses through this interface does not +work. The receive message queue is not implemented, by design. There +is only one receive message queue on a BMC, and that is meant for the +host drivers, not something on the IPMB bus. + +A BMC may have multiple IPMB busses, which bus your device sits on +depends on how the system is wired. You can fetch the channels with +"ipmitool channel info <n>" where <n> is the channel, with the +channels being 0-7 and try the IPMB channels. + Other Pieces ------------ |