Power, Reset, and Clock Management
Table 8-5. Slave Module Mode Settings in PRCM (continued)
MODULEMODE Bit VALUE
Selected Mode
Description
This mode applies to a module when the
PRCM module manages its interface and
functional clocks. The functional clock to
the module remains active unconditionally,
while the PRCM module automatically
0x2
Enabled
asserts/deasserts the module idle request
based on the clock-domain transitions. If
acknowledged by the module, the PRCM
module can gate only the interface clock
to the module.
0x3
Reserved
NA
In addition to the IDLE and STANDBY protocol, PRCM offers also the possibility to manage optional
clocks, through a direct SW control: “OptFclken” bit from programming register.
Table 8-6. Module Clock Enabling Condition
Clock Enabling
Clock Domain is ready
Clock associated with
AND
MStandby is de-asserted
STANDBY protocol
OR
Mwakeup is asserted
Clock Domain is ready
Idle status = FUNCT
Clock associated with IDLE
AND
protocol, as interface clock
OR
Idle status = TRANS
SWakeup is asserted
Clock Domain is ready
Idle status = FUNCT
Clock associated with IDLE
AND
Idle status = IDLE
protocol, as functional clock
OR
Idle status = TRANS
SWakeup is asserted
Clock domain is ready
Optional clock
AND
OptFclken=Enabled ('1')
8.1.3.3
Clock Domain
A clock domain is a group of modules fed by clock signals controlled by the same clock manager in the
PRCM module By gating the clocks in a clock domain, the clocks to all the modules belonging to that
clock domain can be cut to lower their active power consumption (that is, the device is on and the clocks
to the modules are dynamically switched to ACTIVE or INACTIVE (GATED) states). Thus, a clock domain
allows control of the dynamic power consumption of the device. The device is partitioned into multiple
clock domains, and each clock domain is controlled by an associated clock manager within the PRCM
module. This allows the PRCM module to individually activate and gate each clock domain of the device
504
Power, Reset, and Clock Management (PRCM)
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated