Functional Description
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
2-16
ID021414
Non-Confidential
2.4
Power management
The Cortex-A53 processor provides mechanisms and support to control both dynamic and static
power dissipation. The individual cores in the Cortex-A53 processor support four main levels
of power management. This section describes:
•
Power domains
.
•
Power modes
on page 2-17
.
•
Event communication using WFE or SEV
on page 2-25
.
•
Communication to the Power Management Controller
on page 2-26
.
2.4.1
Power domains
Table 2-2
shows the power domains that the Cortex-A53 processor supports:
The separate PDCORTEXA53 and PDL2 power domains can remain active even when all the
cores are powered down. This means the Cortex-A53 processor can continue to accept snoops
from external devices to access the L2 cache.
Figure 2-8 on page 2-17
shows an example of the domains embedded in a
System-on-Chip
(SoC) power domain.
Table 2-2 Power domain description
Power domain
Description
PDCORTEXA53
This includes the SCU, the optional L2 cache controller, and debug registers described as being in the
debug domain.
PDL2
This includes the L2 data RAM, L2 tag RAM, L2 victim RAM, and the SCU duplicate tag RAM.
PDCPU<n
a
>
This includes the optional Advanced SIMD and Floating-point Extension, the L1 TLB, L1 processor
RAMs, and debug registers described as being in the processor domain.
PDCPUADVSIMD<n
a
>
This represents the Advanced SIMD and Floating-point block of core n.
a. <n> where n is 0, 1, 2, or 3. This represents core 0, core 1, core 2, or core 3. If a core is not present, the corresponding Power Domain is not
present.