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[#1]

Deep Sleep Mode of iMX937

I am using iMX95lpddr5 evk, triggered the deep sleep mode want to know about the state, clock frequency and power consumption of suspended and non suspended cores among A55, M7 and M33.

Re: Deep Sleep Mode of iMX937

On i.MX95 LPDDR5 EVK, “deep sleep” maps to the i.MX 95 Suspend / DSM-style low-power cases . The A55 is suspended/power-gated; M33 is not running application workload, typically shown as clock-gated/idle ; M7 depends on whether you suspend it too or keep it as the wake/real-time core. The power numbers in AN14449 are SoC rail/group totals , not per-core power.

Low-power case	Cortex-A55 state / freq	Cortex-M33 state / freq	Cortex-M7 state / freq	DDR state	Reported power
System in DSM	Suspend; clock not detectable	Clock gating; clock not detectable	Suspend; clock not provided	Retention	25.65 mW GROUP_SOC_FULL total
Linux Suspend + CM7 WFI	Suspend / 0	Clock gating or idle / 0	WFI / 400 MHz	Retention	178.48 mW GROUP_SOC_FULL total
Linux Suspend + CM7 CoreMark (TCM)	Suspend / 0	Clock gating or idle / 0	CoreMark / 400 MHz	Retention	197.24 mW GROUP_SOC_FULL total
Linux Suspend + CM7 FlexCAN transaction	Suspend / 0	Clock gating or idle / 0	FlexCAN / 800 MHz	Active, 6400 MT/s	659.71 mW GROUP_SOC_FULL total
Linux Suspend + CM7 NETC / Ethernet	Suspend / 0	Clock gating or idle / 0	NETC / 800 MHz	Active, 6400 MT/s	956.17 mW GROUP_SOC_FULL total
Linux Suspend + WoL	A55 suspended	M33 idle/low-power context	wake-capable configuration; exact core table not in the retrieved chunk	depends on WoL setup	342.72 mW GROUP_SOC_FULL total

A few interpretation notes:

• The i.MX 95 Reference Manual describes Suspend as the maximum-power-saving mode where unnecessary clocks/supplies are off, the Cortex-A55 CPU is fully power-gated, PHYs that can be powered down are off, and VDD_SOC is reduced to suspend voltage.
• In System in DSM , AN14449 explicitly says the usage is CA55=Suspend, CM33=Clock gating, CM7=Suspend, DDR=Retention , and also notes that because CA55 and CM33 are not working, clocks cannot be detected.
• For Linux suspend with M7 kept active, the non-suspended core is CM7 ; its clock is either 400 MHz for WFI/CoreMark retention cases or 800 MHz for FlexCAN/NETC cases, while A55 and M33 show 0 MHz in the case tables.
• The published power data is not isolated per A55/M7/M33 core . AN14449 reports rail/group measurements such as GROUP_SOC_FULL and GROUP_DRAM; for example, DSM reports vdd_arm as 0 mW and vdd_soc as 3.85 mW within a GROUP_SOC_FULL sum of 25.65 mW, but that is still rail-level, not individual-core power.

Takeaway: if M7 is also suspended, DSM is about 25.65 mW; if M7 stays alive during Linux suspend, total SoC power rises from about 178–197 mW at 400 MHz to about 660–956 mW at 800 MHz depending on the peripheral workload.

Re: Deep Sleep Mode of iMX937

For I.Mx95, there are several power mode including RUN mode, Lower power RUN mode, IDLE mode, SUSPEND mode and Battery Backed Secure Module mode. For detailed power consumption data, please refer to IMX95AEC datasheet. For i.Mx937, the device is at preproduction phase and only factsheet is available right now.

Not sure about how the test data come from and what the deep sleep mode you refer to...