STM32G491 (Flash category 4): Flash IAP programming?

[flyer31]

Hi, I would like to re-program only some higher part of flash memory with In-Application-Programming (Chip: STM32G491 - this in RefMan is defined as "Flash category 4" device).

My normal firmware e. g. is running in lower 256kB Flash.

And now I want to re-program the upper 256kB ROM.

Problem: STM32G491 is NO dual bank device (like e. g. STM32G473).

If I write 64bit-word by 64bit word, always waiting the 100usec programming time:

Is there some way that I can do this from Flash code.

Or is it REQUIRED, that I put the Programming code into RAM, and then start the RAM code?

(most easy for me would be, if I e. g. could setup interrupt on Flash program end. Then somehow start the 100usec flash program cycle. And then somehow "Halt normal program flow" until these 100usec finished. And then continue with the next 100usec Programming operation (or stop, if I am finished).

Is this possible?

[Tesla DeLorean]

Sorry, not using the G4, but doesn't just stall/block anyhow?

I've generally programmed these STM32 devices from some tight code in assembler, that's address agnostic, self-contained (no external function dependencies), and readily copied/executed in RAM