I
NTEL
® X
EON
® P
ROCESSOR
7500 S
ERIES
U
NCORE
P
ROGRAMMING
G
UIDE
UNCORE PERFORMANCE MONITORING
2-48
Table 2-29. S_MSR_PMON_OVF_CTRL Register Fields
2.5.3.3
S-Box PMON state - Counter/Control Pairs + Filters
The following table defines the layout of the S-Box performance monitor control registers. The main
task of these configuration registers is to select the event to be monitored by their respective data
counter. Setting the .ev_sel field performs the event selection. The .en bit must be set to 1 to enable
counting.
Additional control bits include:
- .pmi_en governs what to do if an overflow is detected.
- .threshold - If the .threshold is set to a non-zero value, that value is compared against the incoming
count for that event in each cycle. If the incoming count is >= the threshold value, then the event
count captured in the data register will be incremented by 1.
- .invert - Changes the .threshold test condition to ‘<‘
- .edge_detect - Rather than accumulating the raw count each cycle (for events that can increment by
1 per cycle), the register can capture transitions from no event to an event incoming.
- .reset_occ_cnt - Reset 7b occupancy counter associated with this counter.
Table 2-30. S_CSR_PMON_CTL{3-0} Register – Field Definitions
Field
Bits
HW
Reset
Val
Description
clr_ov
3:0
0 Writing ‘1’ to bit in filed causes corresponding bit in ‘Overflow PerfMon
Counter’ field in S_CSR_PMON_GLOBAL_STATUS register to be cleared to
0.
Field
Bits
HW
Reset
Val
Description
ig
63
0 Read zero; writes ignored. (?)
rsv
62:61
0 Reserved; Must write to 0 else behavior is undefined.
ig
60:32
0 Read zero; writes ignored. (?)
threshold
31:24
0 Threshold used for counter comparison.
invert
23
0 Invert threshold comparison. When ‘0’, the comparison will be thresh >=
event. When ‘1’, the comparison will be threshold < event.
enable
22
0 Enable counter.
ig
21
0 Read zero; writes ignored. (?)
pmi_en
20
0 PMI Enable. If bit is set, when corresponding counter overflows, a PMI
exception is sent to the U-Box.w
ig
19
0 Read zero; writes ignored. (?)
edge_detect
18
0 Edge Detect. When bit is set, 0->1 transition of a one bit event input will
cause counter to increment. When bit is 0, counter will increment for
however long event is asserted.
reset_occ_cnt
17
0 Reset Occupancy Counter associated with this counter.
ig
16
0 Read zero; writes ignored. (?)
umask
15:8
0 Unit Mask - select subevent of event.
ev_sel
7:0
0 Event Select