Re:Uptime Lab's CM4 Blade Adds NVMe, TPM 2.0 to Raspberry Pi
by staticassertion on Wednesday August 04, 2021 @07:51PM
(#28067956)
You wouldn't hit a TPM every time you wanted a random number. Your OS would just use it when it wanted to seed its entropy pool.
This is particularly useful at boot when entropy is very low.
Too slow to be useful, and the BCM283x SoC already has an internal RNG:
https://github.com/torvalds/linux/blob/master/drivers/char/h...
> ... or hardware-accelerated hashing
The TPM is on a really slow bus (33 MHz, 4 bits, tons of wait states). Even without any hardware acceleration, hashing on the CPU is much faster.