Re: [PATCH 1/3] hw/misc: Introduce AMD/Xilix Versal TRNG device

[Richard Henderson <richard.henderson@linaro.org>]

On 8/31/23 10:18, Tong Ho wrote:
> This adds a non-cryptographic grade implementation of the
> model for the True Random Number Generator (TRNG) component
> in AMD/Xilinx Versal device family.
> 
> This model is only intended for non-real world testing of
> guest software, where cryptographically strong TRNG is not
> needed.
> 
> This model supports versions 1 & 2 of the Versal TRNG, with
> default to be version 2; the 'hw-version' uint32 property
> can be set to 0x0100 to override the default.
> 
> Other implemented properties:
> - 'forced-prng', uint64
>    When set to non-zero, "true random reseed" is replaced by
>    deterministic reseed based on the given value and other
>    deterministic parameters, even when guest software has
>    configured the TRNG as "true random reseed".  This option
>    allows guest software to reproduce data-dependent defects.
> 
> - 'fips-fault-events', uint32, bit-mask
>    bit 3: Triggers the SP800-90B entropy health test fault irq
>    bit 1: Triggers the FIPS 140-2 continuous test fault irq
> 
> Signed-off-by: Tong Ho<tong.ho@amd.com>
> ---
>   hw/misc/Kconfig                    |   3 +
>   hw/misc/meson.build                |   3 +
>   hw/misc/xlnx-versal-trng.c         | 725 +++++++++++++++++++++++++++++
>   include/hw/misc/xlnx-versal-trng.h |  58 +++
>   4 files changed, 789 insertions(+)
>   create mode 100644 hw/misc/xlnx-versal-trng.c
>   create mode 100644 include/hw/misc/xlnx-versal-trng.h

I don't think you should be inventing another PRNG, or related properties.

We already have qemu/guest-random.h, and the -seed command-line parameter to force the use 
of a deterministic PRNG with a given seed value.


r~