Intel 460GX Software Developer’s Manual page 57

1:0
2.5.3.3 PME[1:0]: Performance Monitoring Event Selection
Address Offset:
Default Value:
The PME registers specify the particular event to track in the performance monitoring counters.
The PXB supports tracking of PCI bus transactions (both specific and generic), and PCI bus signal
assertion. Bus transactions may be qualified by the originating agent and transaction destination.
Accumulated event counts are held in the PMD registers, while the PMR registers specify the
action to performed on event detection.
Bits
15
14
13:10
Note: This field is applicable only if the PCI bus is operated in internal-arbiter mode. If the bus is
operated using an external arbiter, this field must be set to Any Agent to trigger any events.
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Intel® 460GX Chipset Software Developer's Manual
Once configured to count, all counters in the SAC and each PXB can be (nearly)
simultaneously started and stopped using a separate enable.
Reload Mode
Reload has priority over increment. That is, if a Reload event and a count event happen
simultaneously, the count event has no effect.
0 Never Reload
1 Reload when this counter overflows.
2 Reload when the other counter overflows.
3 Reload unless the other counter increments.
E8 - EBh
0000h each
Description
reserved (0)
Count Data Cycles
1: Count data cycles associated with selected event
0: Count the selected event
Initiating Agent Selection
This field qualifies the tracking of bus transactions by limiting event detection to those
transactions issued by specific agents. That is, unless otherwise noted for the specific
event selected (below), the agent initiating the bus transaction must match the selection
specified here for the transaction to be tracked.
0000 Agent 0
0001 Agent 1
0010 Agent 2
0011 Agent 3
0100 Agent 4
0101 Agent 5
0110 reserved
0111 reserved
Transaction Destination Selection
This field qualifies the tracking of bus transactions by limiting event detection to those
transactions directed to a specific resource. That is, unless otherwise noted for the
specific event selected (below), the source or destination of the data must match the
selection specified here for the transaction to be tracked.
00 any
01 Main Memory
reserved
Register Descriptions
Size: 16 bits each
Attribute: Read/Write
1000 reserved
1001 reserved
1010 reserved
1011 reserved
1100 reserved
1101 South bridge
1110 460GX chipset agent (i.e.
outbound)
1111 Any agent
10 PCI Target
11 Parallel Segment Peer
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