Datasheet

Datasheet 75

4.8.21 ERRCMD – Error Command Register (Device #0)

Address Offset: 64–65h

Default Value: 0000h

Access: Read/Write

Size: 16 bits

This register enables various errors to generate a SERR Hub Interface Special cycle. Since the

GMCH does not have a SERR# signal, SERR messages are passed from the GMCH to the ICH4-

M over Hub interface. The actual generation of the SERR message is globally enabled for

Device #0 via the PCI Command register.

Note: An error can generate one and only one Hub Interface Error Special cycle. It is software’s

responsibility to make sure that when an SERR error message is enabled for an error condition,

SMI and SCI error messages are disabled for that same error condition.

Bit Description

15:14 Reserved

13 SERR on FSB Strobe Glitch: When this bit is asserted, the GMCH will generate a HI SERR message

when a glitch is detected on one of the FSB strobes.

12 Reserved

11 SERR on GMCH Thermal Sensor Event:

1 = The GMCH generates a SERR Hub Interface Special cycle on a Thermal Sensor Trip that requires

an SERR. The SERR must not be enabled at the same time as the SMI/SCI for a Thermal Sensor

Trip event.

0 = Software must Write a 1 to clear this status bit.

10 Reserved

9 SERR on LOCK to non-DDR SDRAM Memory:

1 = The GMCH generates an SERR Hub Interface Special cycle when a CPU initiated LOCK

transaction targeting non-DDR SDRAM Memory Space occurs.

0 = Reporting of this condition is disabled.

8 SERR on DDR SDRAM Refresh timeout:

1 = The GMCH generates an SERR Hub Interface Special cycle when a DDR SDRAM Refresh timeout

occurs.

0 = Reporting of this condition is disabled.

7 SERR on DDR SDRAM Throttle Condition:

1 = The GMCH generates an SERR Hub Interface Special cycle when a DDR SDRAM Read or Write

Throttle condition occurs.

0 = Reporting of this condition is disabled.

6 SERR on Receiving Target Abort on Hub Interface:

1 = The GMCH generates an SERR Hub Interface Special cycle when a GMCH originated Hub

interface cycle is terminated with a Target Abort.

0 = Reporting of this condition is disabled.