Data Sheet

Power Management—Ethernet Controller I210
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5.6.1 Advanced Power Management Wake Up
Advanced Power Management Wake Up or APM Wakeup (also known as Wake on LAN) is a feature that
existed in earlier 10/100 Mb/s NICs. This functionality was designed to receive a broadcast or unicast
packet with an explicit data pattern, and then assert a subsequent signal to wake up the system. This
was accomplished by using a special signal that ran across a cable to a defined connector on the
motherboard. The NIC would assert the signal for approximately 50 ms to signal a wake up. The I210
now uses (if configured) an in-band PM_PME message for this functionality.
On power up, the I210 reads the APM Enable bits from the Flash Initialization Control Word 3 into the
APM Enable (APME) bits of the Wakeup Control (WUC) register. These bits control enabling of APM wake
up.
When APM wake up is enabled, the I210 checks all incoming packets for Magic packets. See
Section 5.6.3.1.4 for a definition of Magic packets.
Once the I210 receives a matching Magic packet, and if the WUC.APMPME bit or the PMCSR.PME_En
bits are set to 1b and the WUC.APME bit is set to 1b it:
•Sets the PME_Status bit in the PMCSR register and issues a PM_PME message (in some cases, this
might require asserting the PE_WAKE_N signal first to resume power and clock to the PCIe
interface).
• Stores the first 128 bytes of the packet in the Wake Up Packet Memory (WUPM) register.
• Sets the Magic Packet Received bit in the Wake Up Status (WUS) register.
• Sets the packet length in the Wake Up Packet Length (WUPL) register.
The I210 maintains the first Magic packet received in the Wake Up Packet Memory (WUPM) register
until the software device driver writes a 1b to the WUS.MAG bit.
If the WUC.EN_APM_D0 bit is set to 1b, APM wake up is supported in all power states and only disabled
if a subsequent Flash read results in the WUC.APME bit being cleared or software explicitly writes a 0b
to the WUC.APME bit. If the WUC.EN_APM_D0 bit is cleared APM wake-up is supported only in the D3 or
Dr power states.
Notes:
1. When the WUC.APMPME bit is set a wake event is issued (PE_WAKE_N pin is asserted and a
PM_PME PCIe message is issued) even if the PMCSR.PME_En bit in configuration space is cleared.
To enable disabling of system Wake-up when PMCSR.PME_En is cleared, the software device driver
should clear the WUC.APMPME bit after power-up or PCIe reset.
2. If APM is enabled and the I210 is programmed to issue a wake event on the PCIe, each time a
Magic packet is received, a wake event is generated on the PCIe interface even if the WUS.MAG bit
was set as a result of reception of a previous Magic packet. Consecutive magic packets generate
consecutive Wake events.
5.6.2 ACPI Power Management Wake Up
The I210 supports PCIe power management based wake-up. It can generate system wake-up events
from a number of sources:
• Reception of a Magic packet.
• Reception of a network wake-up packet.
• Detection of a change in network link state (cable connected or disconnected).
• Wake-up by manageability after receiving an unsupported packets for proxying.