MSC8144E Reference Manual, Rev. 3
4-10
Freescale
Semiconductor
Chip-Level Arbitration and Switching System (CLASS)
4.4.2
Watch Point Unit
The CLASS includes a watch point unit (WPU) for each of the initiator interfaces and for each of
the target interfaces. The WPU can compare programmed values to the real transactions and
generate a watch point event when a match occurs.
Note:
For each CLASS module, only one WPEN field can be set among all CnIWPCRx and
CnTWPCRx when snooping watch point events. That is, only one watch point unit can
be active at a time.
Use the following steps to use the watch point unit:
1.
Clear CnPCR.
2.
Clear CnIPCRx and CnTPCR.
3.
For the time-out mechanism, program CnPTOR and set the CnPCR[TOE] bit.
4.
Define the transaction to be monitored by writing the desired configuration to
CnWPCR, CnWPACR, CnWPEACR, and CnWPAMR.
5.
Enable the watch point units through CnIWPCRx and CnTWPCR.
6.
Set the CnWPRCR[CE] bit to enable counting of the watch point events. If you use the
watch point events to enable/disable the profiling unit according to WPCE, clear this bit.
7.
After the measurement are finished check the following registers:
— Read the CnPISR[OVE] bit.
— In time-out mode, read CnPRCR.
— If CnPISR[OVE] is set or if CnPRCR is equal to CnPTOR, the results are not valid.
— Read CnPGCRx to get the number of watch point events during the measurement.
4.4.3
Event Selection
Events are selected using a combination of the CLASS watch point and profiling registers. Table
4-2 lists the measurement modes, the required configuration settings, and the events measured by
the specific CLASS Profiling General Registers for each CLASS module. See Section 4.7 for the
register details.
Table 4-2. CnPGCRx Events Selection
Measurement
Mode
Configuration Settings for Each Mode
Events Measured
CnWPCR
[CE]
CnTPCR
[TT]
CnTPCR
[PMM]
CnIPCRx
[PMM]
CnPGCR0
CnPGCR1
CnPGCR2
CnPGCR3
None selected
0
—
00
00000
—
—
—
—
Initiator Priority
and
Auto-Upgrade
0
—
00
00001
Number of
Initiator
requests
with
Priority 1
Number of
Initiator
requests
with
Priority 2
Number of
Initiator
requests
with
Priority 3
Initiator
Auto-
Upgrade
Summary of Contents for MSC8144E
Page 1: ...MSC8144E Reference Manual Quad Core Media Signal Processor MSC8144ERM Rev 3 July 2009 ...
Page 48: ...MSC8144E Reference Manual Rev 3 xlviii Freescale Semiconductor ...
Page 86: ...MSC8144E Reference Manual Rev 3 1 38 Freescale Semiconductor Overview ...
Page 168: ...MSC8144E Reference Manual Rev 3 3 60 Freescale Semiconductor External Signals ...
Page 242: ...MSC8144E Reference Manual Rev 3 5 26 Freescale Semiconductor Reset ...
Page 314: ...MSC8144E Reference Manual Rev 3 8 24 Freescale Semiconductor General Configuration Registers ...
Page 414: ...MSC8144E Reference Manual Rev 3 10 14 Freescale Semiconductor MSC8144E SC3400 DSP Subsystem ...
Page 452: ...MSC8144E Reference Manual Rev 3 11 38 Freescale Semiconductor Internal Memory Subsystem ...
Page 520: ...MSC8144E Reference Manual Rev 3 12 68 Freescale Semiconductor DDR SDRAM Memory Controller ...
Page 1070: ...MSC8144E Reference Manual Rev 3 21 28 Freescale Semiconductor Timers ...