82598EB Datasheet, PDF (430/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - SMBus Transactions
Table 5-2. Shorthand Field Name
Field Name
S
P
PEC
A
N
Rd
Wr
SMBus START Symbol
SMBus STOP Symbol
Packet Error Code
ACK (Acknowledge)
NACK (Not Acknowledge)
Read Operation (Read Value = 1b)
Write Operation (Write Value = 0b)
Definition
5.3.4.1 SMBus Addressing
The SMBus addresses that 82598EB responds to depends on the LAN mode (teaming/non-teaming). If
the LAN is in teaming mode (fail-over), 82598EB is presented over the SMBus as one device and has
one SMBus address. While in non-teaming mode in the LAN ports, the SMBus is presented as two
SMBus devices on the SMBus (two SMBus addresses). In dual-address mode, all pass-through
functionality is duplicated on the SMBus address, where each SMBus address is connected to a different
LAN port. Note that it is not allowed to configure both ports to the same SMBus address. When a LAN
function is disabled, the corresponding SMBus address is not presented to the BMC (see
Section 5.3.11.1).
The SMBus addressing mode is defined through the SMBus Addressing Mode bit in the EEPROM. The
SMBus addresses are set in SMBus address 0 and SMBus address 1 in the EEPROM. Note that if single-
address mode is set, only the SMBus address 0 field is valid.
The SMBus addresses (enabled from the EEPROM) can be re-assigned using the SMBus ARP protocol.
In addition to the SMBus address values, all parameters of the SMBus (SMBus channel selection,
address mode, and address enable) can be set only through EEPROM configuration. Note that the
EEPROM is read at 82598EB power up and resets.
All SMBus addresses should be in Network Byte Order (NBO); MSB first.
5.3.4.2 SMBus ARP Functionality
The 82598EB supports the SMBus ARP protocol as defined in the SMBus 2.0 specification. 82598EB is a
persistent slave address device so its SMBus address is valid after power-up and loaded from the
EEPROM. 82598EB supports all SMBus ARP commands defined in the SMBus specification both general
and directed.
Note: The SMBus ARP capability can be disabled through the EEPROM.
5.3.4.2.1 SMBus ARP Flow
SMBus ARP flow is based on the status of two flags:
• AV (Address Valid): This flag is set when 82598EB has a valid SMBus address.
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