Intel Phi 7120A SC7120A Data Sheet
Product codes
SC7120A
Document ID Number: 328209 003EN
Intel
®
Xeon Phi™ Coprocessor Datasheet
67
The SMC supports a read only IPMI SDR. It is hard-coded and not end-user updateable.
The SDR can be read in “chunks”, suggested size is 16 bytes or the entire SDR can be
read passing ‘FF’ as the number of bytes to read.
The SDR can be read in “chunks”, suggested size is 16 bytes or the entire SDR can be
read passing ‘FF’ as the number of bytes to read.
6.6.1
IPMB Protocol
The IPMB protocol is a symmetrical byte-level transport for transferring IPMI messages
between intelligent I2C devices. It is a worldwide standard widely used in the server
management industry. In this case, the client requests are sent to the SMC with a
master I2C write.
between intelligent I2C devices. It is a worldwide standard widely used in the server
management industry. In this case, the client requests are sent to the SMC with a
master I2C write.
Although both devices are a master on the bus at different times, the SMC only
responds to requests. With the exception of the address selection algorithm, it does not
initiate master transactions on the bus at any other time during normal operation.
responds to requests. With the exception of the address selection algorithm, it does not
initiate master transactions on the bus at any other time during normal operation.
The commands supported by the SMC are documented below. The specific information
to implement these commands is documented with each command. For byte level
details, refer to the Intelligent Platform Management Bus Communications Protocol
Specification, v1.0
to implement these commands is documented with each command. For byte level
details, refer to the Intelligent Platform Management Bus Communications Protocol
Specification, v1.0
and the Intelligent Platform Management Interface Specification,
v2.0
.
6.6.2
Polled Master-Only Protocol
The polled master-only protocol may be used in the event IPMB is not feasible. The
client sends requests to the SMC using one or more SMC SMBus Write Block commands
then, at a later time, reads the response using one or more SMBus Read Block
commands.
client sends requests to the SMC using one or more SMC SMBus Write Block commands
then, at a later time, reads the response using one or more SMBus Read Block
commands.
6.6.2.1
Polled Master-Only Protocol Clarifications
The polled master-only protocol is loosely based on the IPMI defined SSIF protocol;
however, there have been a few changes made and ambiguities clarified in order to
make the protocol more reliable:
however, there have been a few changes made and ambiguities clarified in order to
make the protocol more reliable:
• The I2C address for the polled master-only protocol and the IPMB protocol are the
same and work together transparently.
• PEC bytes are required for all write commands and are returned with all valid read
responses.
• The maximum SMBus data length is restricted to 32 bytes.
• The SMC ignores write commands that occur while it is internally processing a
• The SMC ignores write commands that occur while it is internally processing a
previous command.
• The SMC does not return valid data while busy internally processing a command.
• A sequence number has been added to help identify the condition where a new
• A sequence number has been added to help identify the condition where a new
write command (using the same NetFn and command as the last command sent)
was corrupted during transit. Without this precaution, two sequential requests of
the same type (i.e., Get Sensor Reading) could result in one sensor’s reading being
mistaken for the other’s.
was corrupted during transit. Without this precaution, two sequential requests of
the same type (i.e., Get Sensor Reading) could result in one sensor’s reading being
mistaken for the other’s.
• SMBAlert is not supported.