Re: which CPUs should call aarch64_add_{sve, pauth, sme}_properties() ?

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

On 6/26/23 18:54, Peter Maydell wrote:
> At the moment:
>   * aarch64_a64fx_initfn() calls aarch64_add_sve_properties()
>   * aarch64_max_tcg_initfn() calls all of
>     aarch64_add_pauth_properties(), aarch64_add_sve_properties(),
>     aarch64_add_sme_properties()
> 
> and it happens that (ignoring 'max') we only have a64fx implementing SVE
> and no CPUs implementing Pauth or SME yet.
> 
> Is the idea that all CPUs (both ones trying to match real hardware
> and ones which are QEMU-specific like 'max') should call these
> functions to set up the properties if they exist? Or is the idea
> that 'max' is special and match-real-hardware CPUs don't need the
> user-facing configurability?

Set up properties if they exist was the idea, I think.

> If the former, maybe it would be better to put these in
> arm_cpu_post_init() so they're automatically called if the CPU
> specific initfn set the ID register value that indicates the
> presence of pauth/sve/sme.

I thought there was some weirdness with kvm and -cpu host.

> I ask because Neoverse-V1 has both SVE and Pauth, and I'm not
> sure if its init fn should be calling these functions.

I would say so.


r~