AMD SB700/710/750 Register Programming Requirements

6.2 USB Device Support to Wake Up System from S3/S4 State
ASIC Rev Register Settings Function/Comment
All Revs SB7x0 PM_IO 0x61 [6] = 1
PM_IO 0x65 [2] = 1 (default)
Enables the USB PME event.
Enables USB resume support.
All Revs SB7x0 PM_IO 0x65 [6] = 1 Enable PME generation for USB Wake event from connect
and disconnect of USB devices.
SATA USB SMBUS PATA AC97 HD AUDIO LPC PCI
RTC ACPI PM REG A-LINK I/O REG XIOAPIC
X
6.3 PHY Power Down Support
Note: BIOS workaround A2 described in Appendix A must be
implemented for this feature to work reliably. Without the
workaround PME Wake for Connect/Disconnect of USB 1.1
devices will not be supported.
ASIC Rev Register Settings Function/Comment
All Revs SB7x0 PM_IO 0x65 [0] = 0 (default)
SATA USB SMBUS PATA AC97 HD AUDIO LPC PCI
RTC ACPI PM REG A-LINK I/O REG XIOAPIC
X
6.4 USB PHY Auto Calibration Setting
For register details, refer to
the sections check-marked
in the SB700/710/750
Register Reference Guide.
This bit = 0 (default) supports USB device wakeup from the
S4/S5 state.
Set the bit to 1 to disable the USB S4/S5 wakeup function.
The analog power supply to USB PHY on the motherboard
can be OFF in this case to save S4/S5 power.
ASIC Rev Register Settings Function/Comment
For register details, refer to
the sections check-marked
in the SB700/710/750
Register Reference Guide.
All Revs SB7x0 EHCI_BAR 0xC0 = 0x00020F00 Enables the USB PHY auto calibration resistor to match
45ohm resistance.
SATA USB SMBUS PATA AC97 HD AUDIO LPC PCI
X
RTC ACPI PM REG A-LINK I/O REG XIOAPIC
For register details, refer to
the sections check-marked
in the SB700/710/750
Register Reference Guide.
© 2009 Advanced Micro Devices, Inc. USB – OHCI & EHCI Controllers (bus-0, dev-18/19, fun-00 ~02/
bus-0, dev-20, fun-05)
AMD SB700/710/750 Register Programming Requirements Page 44