Programmer’s Guide BCM5722
10/15/07
Broadcom Corporation
Document 5722-PG101-R Power Management Page 140
DEVICE ACPI TRANSITIONS
Host software must program the Power Management Control/Status (PMSCR) register to transition the device between D0
and D3 ACPI states. The Power State bit field in the PMSCR (see “Power Management” on page 136) may be programmed
to D0, D1, D2, and D3 states.
The PME signal is enabled in the PMSCR by asserting the PME_Enable bit. Device drivers/BIOS may also read the
PME_Status bit to determine whether the event has been driven; PME_Status is a write to clear bit. The type and supported
power management features for the BCM5722 Ethernet controller are reported in the Power Management Capabilities
(PMC) register (see “Power Management Capabilities Register (Offset 0x4A)” on page 197). System software and BIOS
may read this register to enumerate and detect the power management features supported by the NIC/LOM. For example,
the BCM5722 Ethernet controller can assert PME from both D3 hot and cold states. The PME_Support bit field in the PMC
register will reflect this capability.
DISABLE DEVICE THROUGH BIOS
The BCM5722 Ethernet controllers can be disabled through BIOS by writing the value of DEADDEADh to shared memory
location of B50h. This eliminates the need for BIOS to execute the device specific procedure for disabling the MAC device.
The BIOS must do the following steps to disable the device.
1. Config cycle, write 88h to location 68h.
2. Config cycle, write 0B50h to location 7Ch.
3. Config cycle, write DEADDEADh to location 84h.
Note: The D1 and D2 configurations are not supported in the BCM5722 Ethernet controller. The D1 and D2 bit
configurations are available for applications, where D1 and D2 states are introduced for board level designs—the
bits provide flexibility to the application. The Broadcom reference NIC/LOM designs do not use D1 and D2 states;
therefore, host software should avoid setting these states. Before the Mac is moved into the D3 state, the clocks
and GPIO must be configured (see above sections).
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