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Date:      Wed, 9 Jul 2008 11:31:36 -0400
From:      "Joseph Gleason" <fireduck@gmail.com>
To:        freebsd-questions@freebsd.org
Subject:   Which VIA CPUs have hardware RNG support?
Message-ID:  <7956f3200807090831u1bd6bfddxf78517ae46a32b95@mail.gmail.com>

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I am trying to figure out which VIA CPUs support hardware RNG under
recent FreeBSD.  I've been looking at things on 7.0-RELEASE-p2.  If
there is something that else I should be looking at, please let me
know.

Based on 'man 4 random' I see:
"The only hardware implementation currently is for the
     VIA C3 Nehemiah (stepping 3 or greater) CPU.  More will be added in the
     future."

Poking around in the kernel I see that indeed nehemiah and yarrow seem
to be the only random sources there.

>From 'usr/src/sys/i386/i386/initcpu.c':
SYSCTL_UINT(_hw, OID_AUTO, via_feature_rng, CTLFLAG_RD,
        &via_feature_rng, 0, "VIA C3/C7 RNG feature available in CPU");

Based on all this and some reading on wikipedia, my best guess is that
C3 Nehemiah and later and all C7 support the hardware RNG.  Can anyone
confirm this?



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