Is there more technical info on the ISPU available?

[MFlam.1]

I would like to use the ISPU on the LSM6DSO16ISTR for signal processing of both the internal and a few external sensors. I'm having trouble finding any details on the ISPU itself. How about:

• Instruction set architecture
• Register file
• Boot loader
• Clocking (how fast does it execute instructions?)

Please point me to the technical documentation for this core.

Thanks!