I
NTEL
® X
EON
® P
ROCESSOR
7500 S
ERIES
U
NCORE
P
ROGRAMMING
G
UIDE
UNCORE PERFORMANCE MONITORING
2-5
2.2 U-Box
Performance
Monitoring
The U-Box serves as the system configuration controller for the Intel Xeon Processor 7500 Series.
It contains one counter which can be configured to capture a small set of events.
2.2.1
U-Box PMON Summary
Table 2-5. U-Box Performance Monitoring MSRs
2.2.1.1
U-Box Box Level PMON State
U-Box global state bits are stored in the uncore global state registers. Refer to
Performance Monitoring Control”
for more information.
2.2.1.2
U-Box PMON state - Counter/Control Pairs
The following table defines the layout of the U-Box performance monitor control register. The main task
of this configuration register is to select the event to be monitored by its 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 which governs what to do if an overflow is detected.
- .edge_detect - Rather than accumulating the raw count each cycle, the register can capture
transitions from no event to an event incoming.
Table 2-6. U_MSR_PMON_EVT_SEL Register – Field Definitions
MSR Name
Access
MSR
Address
Size
(bits)
Description
U_MSR_PMON_CTR
RW_RW
0x0C11
64 U-Box PMON Counter
U_MSR_PMON_EV_SEL
RW_RO
0x0C10
32 U-Box PMON Event Select
Field
Bits
HW
Reset
Val
Description
ig
63
0 Read zero; writes ignored. (?)
rsv
62
0 Reserved; Must write to 0 else behavior is undefined.
ig
61:23
0 Read zero; writes ignored. (?)
en
22
0 Local Counter Enable. When set, the associated counter is locally
enabled.
NOTE: It must also be enabled in C_MSR_PMON_GLOBAL_CTL and the
U-Box to be fully enabled.
ig
21
0 Read zero; writes ignored. (?)
pmi_en
20
0 When this bit is asserted and the corresponding counter overflows, a PMI
exception is sent to the U-Box.
ig
19
0 Read zero; writes ignored. (?)
edge_detect
18
0 When asserted, the 0 to 1 transition edge of a 1 bit event input will cause
the corresponding counter to increment. When 0, the counter will
increment for however long the event is asserted.
ig
17:8
0 Read zero; writes ignored. (?)
ev_sel
7:0
0 Select event to be counted.