Broadcom BCM5722 - Table 52: GPIO Usage for BCM5700;BCM5701 Power Management for Broadcom Drivers; Table 53: GPIO Usage for BCM5703 C;BCM5703 S and Later Power Management for Broadcom Drivers; Table 54: BCM5722 Ethernet Controller Power Pins

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BCM5722 Programmer’s Guide

10/15/07

Broadcom Corporation

Page 139 Power Management Document 5722-PG101-R

GPIO

The use of GPIO pins for power management is design-specific, though Broadcom-delivered drivers use GPIO pins in the

manner listed in Table 52 and Table 53. This usage is only applicable when the BCM5722 Ethernet controller is configured

for a NIC design; it is not applicable to LAN-on-Motherboard (LOM) designs.

POWER SUPPLY IN D3 STATE

Table 54 shows the power supply to various power pins on the BCM5722 Ethernet controller. This table assumes that host

software has switched power regulators using GPIO pins 0, 1, and 2.

CLOCK CONTROL

Certain functional blocks in the MAC architecture should be powered down before a transition to D3 ACPI state. MAC clock

generators/PLLs drive transistor level logic, which switch states on every clock pulse. Transistor level switching consumes

power (mW). Software should selectively disable clocking to non-essential functional blocks. Software must set the

Enable_Clock_Control_Register bit in the Miscellaneous Host Control register (see “Miscellaneous Host Control Register

(Offset 0x68)” on page 204); the assertion of this bit allows host software to configure the PCI clock control register. The

following clock bits should be configured in the PCI Clock Control register (see “PCI Clock Control Register (Offset 0x74)”

on page 207):

• RX RISC clock disable

• Select alternate clock—the 133-MHz PLL is not used as reference clock.

Table 52: GPIO Usage for BCM5700/BCM5701 Power Management for Broadcom Drivers

Function Description GPIO0 GPIO1 GPIO2

VAux Switches the BCM5722 Ethernet controller to use VAux power 1 1 0

Table 53: GPIO Usage for BCM5703C/BCM5703S and Later Power Management for Broadcom Drivers

a. x = Don't Care

Function Description GPIO0 GPIO1 GPIO2

VAux Sequence for switching to VAux 0 0 1

111

110

VMain Sequence for switching to VMain x 1 x

x0x

x1x

Table 54: BCM5722 Ethernet controller Power Pins

Pin D3 Normal D3 Hot D3 Cold

VDD_CORE PCI Slot Vaux Vaux

VDD_IO PCI Slot Vaux Vaux

VDD_IO-PCI PCI Slot PCI Slot No Power