307013-003 Datasheet, PDF (116/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

Functional Description
5.4.1
correctly and for capability reporting. A major advantage of ASF is that it provides
these services during the time that software is unable to do so (e.g., during a low-
power state, during boot-up, or during an operating system hang) but are not
precluded from running in the working state.
The ASF controller communicates to the system and the LAN controller logic through
the SMBus connections. The first SMBus connects to the host SMBus controller (within
the ICH7) and any SMBus platform sensors. The SMBus host is accessible by the
system software, including software running on the operating system and the BIOS.
Note that the host side bus may require isolation if there are non-auxiliary devices that
can pull down the bus when un-powered. The second SMBus connects to the LAN
controller. This second SMBus is used to provide a transmit/receive network interface.
The stimulus for causing the ASF controller to send packets can be either internal or
external to the ASF controller. External stimuli are link status changes or polling data
from SMBus sensor devices; internal events come from, among others, a set of timers
or an event caused by software.
The ASF controller provides three local configuration protocols via the host SMBus. The
first one is the SMBus ARP interface that is used to identify the SMBus device and allow
dynamic SMBus address assignment. The second protocol is the ASF controller
command set that allows software to manage an ASF controller compliant interface for
retrieving info, sending alerts, and controlling timers.
ICH7 provides an input and an output EEPROM interface. The EEPROM contains the LAN
controller configuration and the ASF controller configuration/packet information.
ASF Management Solution Features/Capabilities
• Alerting
— Transmit SOS packets from S0–S5 states
— System Health Heartbeats
— SOS Hardware Events
- System Boot Failure (Watchdog Expires on boot)
- LAN Link Loss
- Entity Presence (on ASF power-up)
- SMBus Hung
- Maximum of eight Legacy Sensors
- Maximum of 128 ASF Sensor events
— Watchdog Timer for operating system lockup/System Hang/Failure to Boot
— General Push support for BIOS (POST messages)
• Remote Control
— Presence Ping Response
— Configurable Boot Options
— Capabilities Reporting
— Auto-ARP Support
— System Remote Control
- Power-Down
- Power-Up
- Power Cycle
- System Reset
— State-Based Security – Conditional Action on WatchDog Expire
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Intel ^® ICH7 Family Datasheet