Chapter 08 Power, Reset, and Clock Management (PRCM).pdf

www.ti.com Power, Reset, and Clock Management
Table 8-5. Slave Module Mode Settings in PRCM (continued)
MODULEMODE Bit VALUE Selected Mode Description
0x2 Enabled
0x3 Reserved NA
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
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.
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 associated with
STANDBY protocol
AND
OR
Clock Domain is ready
MStandby is de-asserted
Mwakeup is asserted
Clock Domain is ready
Clock associated with IDLE
protocol, as interface clock
AND
OR
Idle status = FUNCT
Idle status = TRANS
Clock Domain is ready
SWakeup is asserted
Clock associated with IDLE
protocol, as functional clock
AND
OR
Idle status = FUNCT
Idle status = IDLE
Idle status = TRANS
8.1.3.3 Clock Domain
Optional clock AND
Clock domain is ready
OptFclken=Enabled ('1')
SWakeup is asserted
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
SPRUH73E–October 2011–Revised May 2012 Power, Reset, and Clock Management (PRCM)
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