Keeping peripherals in perpetual reset

[SZano]

Is it ok to keep unused peripherals in perpetual reset, by leaving their RCC_APBRSTR_*RST (or similar) bit set?
Maybe differences in power consumption?
This is not for a specific STM32 family.

I'm just looking for advice by people with more experience, about possible pitfalls of doing so.

[SofLit]

Hello,

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@SZano wrote:

Is it ok to keep unused peripherals in perpetual reset, by leaving their RCC_APBRSTR_*RST (or similar) bit set?

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You can do it, but what is the purpose?

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@SZano wrote:

Maybe differences in power consumption?

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For power consumption, just do not clock the peripherals is sufficient. 

[SZano]

At startup it's better to reset everything (e.g. in case a faulty bootloader leaves some peripherals in an unknown state); then, why not leave them in reset until you actually need them? When you do, you clock them, and then take them out of reset.

Isn't there anything reset-related that is asynchronous, and so could be consuming even when no clock is present?

The reset works (at least partially) even when no clock is present, so there must be some asynchronous logic in it.

[SofLit · Accepted solution]

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@SZano wrote:

At startup it's better to reset everything (e.g. in case a faulty bootloader leaves some peripherals in an unknown state);

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Yes you can do that.

Most of the peripherals has a synchronous reset. I cannot confirm it for all of them.