LPC/FWH Interface Configuration
11-2
Intel® 460GX Chipset Software Developer’s Manual
11.1.3
PCICMD–PCI Command Register (Function 0)
Address Offset:
04–05h
Default Value:
0007h
Attribute:
Read/Write
This 16-bit register provides basic control over the IFB's ability to respond to PCI cycles.
11.1.4
PCISTS–PCI Device Status Register (Function 0)
Address Offset:
06–07h
Default Value:
0280h
Attribute:
Read/Write
The PCISTS Register reports the occurrence of a PCI master-abort by the IFB or a PCI target-abort
when the IFB is a master. The register also indicates the IFB DEVSEL# signal timing.
Bit
Description
15:10
Reserved.
9
Fast Back-to-Back Enable (Not Implemented). This bit is hardwired to 0.
8
SERR# Enable (SERRE). 1=Enable. 0=Disable. When enabled (and DLC Register, bit 3=1),
a delayed transaction time-out causes the IFB to assert the SERR# signal. The PCISTS
register reports the status of the SERR# signal.
7:5
Reserved.
4
Postable Memory Write Enable (Not Implemented). This bit is hardwired to 0.
3
Special Cycle Enable (SCE). 1=Enable, the IFB recognizes Shutdown special cycle.
0=Disable, the IFB ignores all PCI Special Cycles.
2
Bus Master Enable (Not Implemented). The IFB does not support disabling its Function 0
bus master capability. This bit is hardwired to 1.
1
Memory Access (Not Implemented). The IFB does not support disabling Function 0 access
to memory. This bit is hardwired to 1.
0
I/O Space Access Enable (Not Implemented). The IFB does not support disabling its
Function 0 response to PCI I/O cycles. This bit is hardwired to 1.
Bit
Description
15
Detected Parity Error (Not Implemented). Read as 0.
14
Signaled SERR# Status (SERRS)–R/WC. When the IFB asserts the SERR# signal, this bit is
set to 1. Software clears this bit by writing a 1 to it.
13
Master-Abort Status (MAS)–R/WC. When the IFB, as a master (for Function 0), generates a
master-abort, MAS is set to a 1. Software sets MAS to 0 by writing a 1 to this bit location.
12
Received Target-Abort Status (RTA)–R/WC. When the IFB is a master on the PCI Bus (for
Function 0) and receives a target-abort, this bit is set to a 1. Software sets RTA to 0 by writing
a 1 to this bit location.
11
Signaled Target-Abort Status (STA)–R/WC. This bit is set when the IFB LPC bridge Function
is targeted with a transaction that the IFB terminates with a target abort. Software sets STA to
0 by writing a 1 to this bit location.
10:9
DEVSEL# Timing Status (DEVT)–RO. The IFB always generates DEVSEL# with medium
timing for Function 0 I/O cycles. Thus, DEVT=01. This DEVSEL# timing does not include
Configuration cycles.
Summary of Contents for 460GX
Page 1: ...Intel 460GX Chipset System Software Developer s Manual June 2001 Document Number 248704 001 ...
Page 20: ...Introduction 1 8 Intel 460GX Chipset Software Developer s Manual ...
Page 80: ...System Architecture 3 8 Intel 460GX Chipset Software Developer s Manual ...
Page 90: ...System Address Map 4 10 Intel 460GX Chipset Software Developer s Manual ...
Page 98: ...Memory Subsystem 5 8 Intel 460GX Chipset Software Developer s Manual ...
Page 146: ...AGP Subsystem 7 16 Intel 460GX Chipset Software Developer s Manual ...
Page 170: ...IFB Register Mapping 9 6 Intel 460GX Chipset Software Developer s Manual ...
Page 190: ...IFB Usage Considerations 10 20 Intel 460GX Chipset Software Developer s Manual ...
Page 232: ...LPC FWH Interface Configuration 11 42 Intel 460GX Chipset Software Developer s Manual ...
Page 244: ...IDE Configuration 12 12 Intel 460GX Chipset Software Developer s Manual ...
Page 258: ...Universal Serial Bus USB Configuration 13 14 Intel 460GX Chipset Software Developer s Manual ...
Page 270: ...SM Bus Controller Configuration 14 12 Intel 460GX Chipset Software Developer s Manual ...
Page 288: ...PCI LPC Bridge Description 15 18 Intel 460GX Chipset Software Developer s Manual ...
Page 294: ...IFB Power Management 16 6 Intel 460GX Chipset Software Developer s Manual ...