Re: [PATCH v3 0/4] riscv: zicntr/zihpm flags and disable support

[Clément Chigot]

Hi Daniel,

This series is triggering warnings when instantiating a CPU having a
spec version older than 1.12.
  | $ qemu-system-riscv32 -M sifive_e
  | qemu-system-riscv32: warning: disabling zicntr extension for hart
0x00000000 because privilege spec version does not match
  | qemu-system-riscv32: warning: disabling zihpm extension for hart
0x00000000 because privilege spec version does not match

And IIUC cpu-tcg.c:riscv_cpu_disable_priv_spec_isa_exts(), they will
end up being disabled as a result of these warnings.

I think these two extensions should be skipped in the above function.
Though we can also disable them on purpose in those old CPUs. WDYT ?

Thanks,
Clément

On Mon, Oct 23, 2023 at 5:40 PM Daniel Henrique Barboza
<dbarboza@ventanamicro.com> wrote:
>
> Hi,
>
> In this v3 the patches that added the extensions flags were squashed
> with the patches that handled the disablement of the extensions in TCG,
> as suggested by Alistair in v2.
>
> No other change made. Patches based on Alistair's riscv-to-apply.next.
>
> Patches missing acks: patch 3
>
> Changes from v2:
> - patch 2: squashed with patch 1
> - patch 5: squashed with patch 4
> - v2 link: 
> https://lore.kernel.org/qemu-riscv/20231017221226.136764-1-dbarboza@ventanamicro.com/
>
> Daniel Henrique Barboza (4):
>   target/riscv: add zicntr extension flag for TCG
>   target/riscv/kvm: add zicntr reg
>   target/riscv: add zihpm extension flag for TCG
>   target/riscv/kvm: add zihpm reg
>
>  target/riscv/cpu.c         | 15 +++++++++++++++
>  target/riscv/cpu_cfg.h     |  2 ++
>  target/riscv/csr.c         |  4 ++++
>  target/riscv/kvm/kvm-cpu.c |  2 ++
>  target/riscv/tcg/tcg-cpu.c | 21 +++++++++++++++++++++
>  5 files changed, 44 insertions(+)
>
> --
> 2.41.0
>
>