This chapter describes the different power modes available on the FE310-G002. The
FE310-G002 supports three power modes: Run, Wait, and Sleep.
Run mode corresponds to regular execution where the processor is running. Power consump-
tion can be adjusted by varying the clock frequency of the processor and peripheral bus, and by
enabling or disabling individual peripheral blocks. The processor exits run mode by executing a
"Wait for Interrupt" (WFI) instruction.
When the processor executes a WFI instruction it enters Wait mode, which halts instruction exe-
cution and gates the clocks driving the processor pipeline. All state is preserved in the system.
The processor will resume in Run mode when there is a local interrupt pending or when the
PLIC sends an interrupt notification. The processor may also exit wait mode for other events,
and software must check system status when exiting wait mode to determine the correct course
of action.
Sleep mode is entered by writing to a memory-mapped register
pmusleep
in the power-man-
agement unit (PMU). The
pmusleep
register is protected by the
pmukey
register which must be
written with a defined value before writing to
pmusleep
.
The PMU will then execute a power-down sequence to turn off power to the processor and main
pads. All volatile state in the system is lost except for state held in the AON domain. The main
output pads will be left floating.
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Содержание FE310-G002
Страница 1: ...SiFive FE310 G002 Manual v19p05 SiFive Inc ...
Страница 11: ...Figure 1 FE310 G002 top level block diagram Copyright 2019 SiFive Inc All rights reserved 9 ...
Страница 15: ...Chapter 2 List of Abbreviations and Terms 13 ...
Страница 23: ...Chapter 4 Memory Map The memory map of the FE310 G002 is shown in Table 4 21 ...