Methods for entering Low Power Modes. Qwiic QuickLogic Thing Plus - EOS S3

32.2.2

Methods for entering Low Power Modes

Each power domain may be placed in a low power mode (shutdown, deep sleep, or light sleep, depending on which are supported by the domain) by M4 firmware or by the TLC writing to a control bit. (See also discussion of Interfacing with an AP).

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See TLC section for details on TLC accessing M4 memory/register space.

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See description on entering low power mode in respective sections.

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Some power domains can be put in a low power mode by PMU hardware driven by an event.

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Some domains only support low power state through shutdown.

32.2.2.1

Software sources for initiating low-power modes

The following table summarizes the software source initiating the low power mode entry for each power domain. Software sources are not maskable.

See also: relevant PMU register fields.

EOS S3 TRM (r1.01a) Confidential Page 297

AD0

AD1

AD2

AD3

AD4

AD5

Table 32-2: Software triggering of Low Power Modes

Power Domain

M4

FFE

FB

PF

A1 eFuse

I2S

SDMA

Software Source to Enter Low Power Mode

WFI/WFE ARM instruction code

DS or SD: PMU.FFE_FB_PF_SOFTWARE_PD[0]

Based on: FFE_POWER_MODE_CFG

DS or SD: PMU.FFE_FB_PF_SOFTWARE_PD[1]

Based on: FB_POWER_MODE_CFG

DS or SD: PMU.FFE_FB_PF_SOFTWARE_PD[2]

Based on: PF_POWER_MODE_CFG

SD: PMU.AUDIO_SOFTWARE_PD[0]

SD: PMU.AUDIO_SOFTWARE_PD[1]

SD: PMU.AUDIO_SOFTWARE_PD[2]

SD: PMU.AUDIO_SOFTWARE_PD[3]

SD: PMU.AUDIO_SOFTWARE_PD[4]

SD: PMU.AUDIO_SOFTWARE_PD[5]

DS or SD: PMU.MISC_SOFTWARE_PD[6]

Based on: A1_POWER_MODE_CFG

SD: PMU.MISC_SOFTWARE_PD[2]

SD: PMU.MISC_SOFTWARE_PD[5]

DS or SD: PMU.MISC_SOFTWARE_PD[0]

Based on: SDMA_POWER_MODE_CFG

M4SRAM[15:12] SD: PMU.M4SRAM_SOFTWARE_PD[15:12]

M4SRAM[11:0] SD: PMU.M4SRAM_SOFTWARE_PD[11:0]

PF SRAM

FFE SRAM

AD1 (Left)

SRAM

AD2 (Right)

SRAM

SDMA SRAM

SD: PMU. PF_MEM_CTRL_1

DS: PMU.FFE_MEM_CTRL_0

SD: PMU.FFE_MEM_CTRL_1

DS: PMU.AUDIO_MEM_CTRL_0

SD: PMU.AUDIO_MEM_CTRL_1

DS: PMU.AUDIO_MEM_CTRL_0

SD: PMU.AUDIO_MEM_CTRL_1

DS: PMU.SDMA_MEM_CTRL_0

SD: PMU.SDMA_MEM_CTRL_1

Alternate Software Source

DS: M4_MEM_CTRL_0

SD: M4_MEM_CTRL_1

DS: M4_MEM_CTRL_0

SD: M4_MEM_CTRL_1

EOS S3 TRM (r1.01a) Confidential Page 298