AMD SB600 - page 111

©2008 Advanced Micro Devices, Inc. SMBus Module and ACPI Block (Device 20, Function 0)
AMD SB600 Register Reference Manual Proprietary Page 111
GPIO_69_68_66_65_Cntrl - RW – 16 bits - [PCI_Reg: 7Eh]
Field Name Bits Default Description
GPIO_Out_En# 7:4 Fh GPIO output port enable for each of the GPIO port
0: Output = GPIO_Out
1: Output = tristate
GPIO_Status 11:8 - GPIO input status for each of the GPIO port
Reserved 15:12 0h
GPIO_69_68_66_65_Cntrl register
GPIO_3_to_0_Cntrl - RW – 16 bits - [PCI_Reg: 80h]
Field Name Bits Default Description
GPIO_Out 3:0 0h Write 1 to set and 0 to clear each of the GPIO port providing
the corresponding bits [7:4] are enabled
Bit[0] for GPIO0/ SSMUXSEL
Bit[1] for GPIO1/ROM_CS#
Bit[2] for GPIO2/SPKR
Bit[3] for GPIO3/FANOUT0
GPIO_Out_En# 7:4 Fh GPIO output port enable for each of the GPIO port
0: Output = GPIO_Out
1: Output = tristate
For GPIO1, this is applicable only if we are not using the
external PCI bus as the ROM interface.
GPIO_Status 11:8 - GPIO input status for each of the GPIO port
Reserved 15:12 0h
GPIO_3_to_0_Cntrl register
GPIO_32_31_14_13_Cntrl - RW – 16 bits - [PCI_Reg: 82h]
Field Name Bits Default Description
GPIO_Out 3:0 0h Write 1 to set and 0 to clear each of the GPIO port providing
the corresponding bits [7:4] and [15:12] are enabled
Bit[0] for GPIO13/LAN_RST#
Bit[1] for GPIO14/ROM_RST#
Bit[2] for GPIO31/SPI_HOLD#
Bit[3] for GPIO32/SPI_CS#
GPIO_Out_En# 7:4 Fh GPIO output port enable for each of the GPIO port
0: Output = GPIO_Out
1: Output = tristate
GPIO_Status 11:8 - GPIO input status for each of the GPIO port
GPIO_Enable 15:12 0h GPIO function enable for each of the GPIO port
0: GPIO disabled
1: GPIO enabled
GPIO_32_31_14_13_Cntrl register
Smbus Base Address - R – 32 bits - [PCI_Reg: 90h]
Field Name Bits Default Description
IO/Memory 0 1b 1 = IO
0 = Memory
Reserved 3:1 000b
SmBusBaseAd 31:4 0000000h SMBus Base Address
Smbus Base Address register (also accessible through 10h)