Re: [PATCH] hw/arm: Add 'virtm' hardware

[Peter Maydell <peter.maydell@linaro.org>]

On Fri, 26 Jun 2020 at 00:07, Keith Packard <keithp@keithp.com> wrote:
>
> 'virtm' is a hardware target that is designed to be used for compiler
> and library testing on Cortex-M processors. It supports all cortex-m
> processors and includes sufficient memory to run even large test
> cases.
>
> Signed-off-by: Keith Packard <keithp@keithp.com>

So, I'm really dubious about adding more "virtual"
not-real-hardware boards. We have "virt" because we
absolutely have to have it for KVM purposes; but otherwise
"emulate real hardware" gives us a concrete specification
of what we're trying to do and tends to lead us into fewer
messy swamps than making up virtual platforms does.

For instance, this board model claims to handle the M33
but makes no attempt to set up any of the TrustZone
related components like the IDAU, so it isn't really
a useful platform for that CPU. You also enable bitband,
which is maybe plausible for Cortex-M3/M4 but not for the
others. This is the kind of area where having a real
hardware system to check against means we make the
right choices about what does or doesn't need to be
present.

thanks
-- PMM