Datasheet

Configuration Registers
3-48 Intel
®
E8870 Scalable Node Controller (SNC) Datasheet
3.10.3 PMINIT: Timer Initial Value Register
The contents of this register is preloaded into the Interval Timer at the start of each sample period.
A sample period is initiated by setting the Timer Enable bit in the PTCTL register or is
automatically re-initiated in the repetitive mode after the completion of each sample interval.
3.10.4 PMTIM: Timer Current Value
This is the value of the Interval Timer. After reset, it will have a value of FFFF_FFFFh, and after a
timer sample interval has expired, it will have a value of 0000_0000h. The actual count value of the
timer is reflected in this register during the sample interval.
3.10.5 FSBPMD[1:0]: Processor Bus Performance Monitor Data
This is the performance monitor counter. The overflow bit can be cleared via the PMR register
without perturbing the value of the counter. This counter is reset at the beginning of a sample
period unless preloaded since a prior sample. Therefore, the counter can be preloaded to cause an
early overflow, otherwise it will be reset at the start of a sample period.
3.10.6 FSBPMC[1:0]: Processor Bus Performance Compare
The compare register can be used in three different ways as selected in the “Compare Mode” field
of the PMR register. First, when PMD is incremented, the value of PMD is compared to the value
of PMC. If PMD is greater than PMC, this status is reflected in the PERFCON register and/or on
EV pins as selected in the “Event Status Output” field of the PMR register. Secondly, update the
PMC register with the value of PMD if the PMD register exceeds the contents of PMC.
Device: NodeID
Function: 3
Offset: 54h
Bit Attr Default Description
31:0 RW FFFF_FFFFh
Initial value of the Countdown Timer
This value is loaded when the contents of the timer is 0 and the timer is
enabled. This field, together with the PTCTL Timer Prescale field define the
sample interval.
Device: NodeID
Function: 3
Offset: 58h
Bit Attr Default Description
31:0 RO FFFF_FFFFh Current Value of the Countdown Timer.
Device: NodeID
Function: 3
Offset: A8h (FSBPMD0), E8h(FSBPMD1)
Bit Attr Default Description
31 RW 0 Overflow.
30:0 RW 0 Current Counter Value.