Register Descriptions

00 0010b All PCI Clocks

00 0100b Idle Bus Cycles

00 0111b All Disconnect Events

00 1000b Lock Asserted Clocks

00 1001b Lock Asserted Events

00 1011b I/O Reads - Events

00 1101b I/O Writes - Events

00 1111b Memory Read Events

01 0001b Memory Write Events

01 0011b SRAM Read Events

01 0101b SRAM Write Events

01 0111b Write Combining Events

01 1000b WBF# Active - Clocks

01 1001b WBF# Active - Events

01 1011b Retry Read that’s not Delayed - Events

01 1101b Retry Write because no Write Slot available - Events

01 1110b Count PCI clocks waiting (Devsel and !IRDY and TRDY) 10 0000b Count PCI clocks waiting (Devsel and IRDY and !TRDY) 10 0010b Count PCI clocks data is transferring

7reserved(0).

6:5 Disable Source

Selects event that will disable the performance monitor.

00b Never Disable.

01b Disable when counter overflows.

10b Disable on falling edge of GXB Event 0.

11b Disable on falling edge of GXB Event 1.

4:3 Enable Source

Selects event that will enable the performance monitor.

00b Never Enable.

01b Enable Always (with this setting, the only meaningful setting for bits 6:5 is 00b). 10b Enable on rising edge of GXB Event 0.

11b Enable on rising edge of GXB Event 1.

2:0 Reload Control

Selects event that will control the Reloading of the performance monitor with the value written into the associated PMD register.

000b Never Reload.

001b Reload when counter overflows.

010b Reload on GXB Event 0 Asserted.

011b Reload on GXB Event 1 Asserted.

100b Reload on GXB Event 0 Asserting edge.

101b Reload on GXB Event 1 Asserting edge.

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Intel® 460GX Chipset Software Developer’s Manual