Datasheet

Processor Uncore Configuration Registers
530 Datasheet, Volume 2
4.6.2.4 PmonCntrCfg_[0:4]—Performance Counter Control Register
PmonCntrCfg
Bus: 1 Device: 8 Function: 2 Offset: D8h, DCh, E0h, E4h, E8h
Bus: 1 Device: 9 Function: 2 Offset: D8h, DCh, E0h, E4h, E8h
Bus: 1 Device: 14 Function: 1 Offset: D8h, DCh, E0h, E4h, E8h
Bus: 1 Device: 16 Function: 0, 1,4,5 Offset: D8h, DCh, E0h, E4h, E8h
Bus: 1 Device: 19 Function: 1 Offset: D8h, DCh, E0h, E4h, E8h
Bit Attr
Reset
Value
Description
31:24 RW-V 00h
Threshold
This field is compared directly against an incoming event value for events that
can increment by 1 or more in a given cycle. Since the widest event from the
UnCore is 7bits (queue occupancy), bit 31 is unused. The result of the
comparison is effectively a 1 bit wide event; that is, the counter will be
incremented by 1 when the comparison is true (the type of comparison depends
on the setting of the ’invert’ bit - see bit 23 below) no matter how wide the
original event was. When this field is zero, threshold comparison is disabled and
the event is passed without modification.
23 RW-V 0h
Invert
This bit indicates how the threshold field will be compared to the incoming
event. When 0, the comparison that will be done is threshold  event. When set
to 1, the comparison that will be done is inverted from the case where this bit is
set to 0; that is, threshold < event. The invert bit only works when 
Threshold != 0. Thus, to invert a non-occupancy event (like LLC Hit), set the
threshold to 1.
22 RW-V 0h
Counter Enable
This field is the local enable for the PerfMon Counter. This bit must be asserted
in order for the PerfMon counter to begin counting the events selected by the
'event select', 'unit mask', and 'internal' bits (see the fields below). There is one
bit per PerfMon Counter. If this bit is set to 1 but the Unit Control Registers have
determined that counting is disabled, then the counter will not count.
21 RW-V 0h
Internal
This bit needs to be asserted if the event which needs to be selected is an
internal event. There will be some hardware that will disable counting on locked
parts. This will be reused from DFX. This is a WIP. Note that MSR counters will
signal GP if someone attempts to write to this bit on regular parts. This will not
be the case on PCI CFG counters because ucode is not a part of the access flow.
20 RW-V 0h
Overflow Enable
Setting this bit will enable the counter to send an overflow signal. If this bit is
not set, the counter will wrap around when it overflows without triggering
anything. If this bit is set and the Unit’s configuration register has Overflow
enabled, then a signal will be transmitted to the Ubox.
19 RV 0h
ThreadID Filter Enable
ThreadID filter enable. This is only used by Cbo. For other units, it is Reserved.
18 RW-V 0h
Edge Detect
Edge Detect allows one to count either 0 to 1 or 1 to 0 transitions of a given
event. By using edge detect, one can count the number of times L0s mode was
enterred (by detecting the rising edge).
Edge detect only works in conjunction with thresholding. This is true even for
events that can only increment by 1 in a given cycle (like the L0s example
above). In this case, set a threshold of 1. One can also use Edge Detect with
queue occupancy events. For example, to count the number of times when the
TOR occupancy was larger than 5, select the TOR occupancy event with a
threshold of 5 and set the Edge Detect bit.
Edge detect can also be used with the invert. This is generally not particularly
useful, as the count of falling edges compared to rising edges will always on
differ by 1.
17 WO 0h
Counter Reset
When this bit is set, the corresponding counter will be reset to 0. This allows for
a quick reset of the counter when changing event encodings.