Re: [PATCH v6 24/24] target/arm: Define neoverse-n1

[Zenghui Yu]

On 2022/8/11 0:47, Peter Maydell wrote:
> On Wed, 10 Aug 2022 at 14:14, Zenghui Yu <yuzenghui@huawei.com> wrote:
> > The r4p1 TRM says that the Neoverse N1 core supports SPE (the value
> > of ID_AA64DFR0.PMSVer is 0b0001) but do we really support SPE
> > emulation in QEMU?
> >
> > The guest immediately received an unexpected exception (with EC==0,
> > at EFI stage) when I tried to boot it using something like:
> >
> > /path/to/qemu-system-aarch64 \
> > -M virt,gic-version=3,virtualization=on \
> > -cpu neoverse-n1 -accel tcg \
> > -bios QEMU_EFI.fd [...]
> >
> > and QEMU shouted that "read access to unsupported AArch64 system
> > register op0:3 op1:0 crn:9 crm:10 op2:7", which told us that the
> > guest attempted to read the PMBIDR_EL1 register.
>
> No, we don't emulate SPE. We should probably not advertise it
> (we might do a no-op implementation eventually).
>
> What guest is this ?

I guess basically anything that starts playing with SPE. I used Linux
and both stable-5.15 and mainline kernel can't boot.

Zenghui