Am Sonntag, 14. August 2016, 01:33:32 CEST schrieb Jeffrey Walton: Hi Jeffrey, > Hi Everyone, > > I have a MIPSEL ci20 dev board for testing. The board has a hardware > based rng, but its suffering entropy depletion. I have Debian's > rng-tools package installed. > > The board lacks /dev/hwrng. /dev/random blocks indefinitely after > draining the device. "Indefinitely" may not be accurate, but I killed > a program that waited over 4 hours for 16 bytes after draining > /dev/random. > > The ci20's documentation is a bit scant, but it can be found at > http://mipscreator.imgtec.com/CI20/hardware/soc/JZ4780_PM.pdf. I'm not > sure what the output rate is, but it seems to be capable of one > machine word (4 bytes) every few milliseconds. Without a delay, I can > see values being shifted into the register mapped at 0x100000DC. > > I have a few questions: > > * Is there a driver for JZ4780 rng? What is the PCI ID? > * Is there a particular package for the driver that needs to be installed? > * What causes/triggers /dev/hwrng to replenish /dev/random? Using rngd which is triggered by /dev/random automatically when its entropy level falls below a threshold. Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
