Re: x86/random: Speculation to the rescue

From: Pavel Machek
Date: Wed Oct 09 2019 - 04:02:45 EST


Hi!

> > I have many systems including SoC here, but technology needed for NAND
> > flash is different from technology for CPU, so these parts do _not_
> > share a silicon die. They do not even share same package. (Also RTC
> > tends to be on separate chip, connected using i2c).
>
> NAND flash requires ECC so is likely to be async.
> But I2C is clocked from the cpu end - so is fixed.

RTC i2c may be clocked from the CPU end, but the time source needs to
work when machine is off, so that has a separate crystal for
timekeeping.


> Also an embedded system could be booting off a large serial EEPROM.
> These have fixed timings and are clocked from the cpu end.

Have you seen such system running Linux?

Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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