Re: [Qemu-devel] [PATCH 6/7] arm/virt: enable PSCI emulation support for system emulation

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

On 5 May 2014 17:00, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <rob.herring@linaro.org>
>
> Now that we have PSCI emulation, enable it for the virt platform.
> This simplifies the virt machine a bit now that PSCI and SMP no longer
> need to be KVM only features.
>
> Signed-off-by: Rob Herring <rob.herring@linaro.org>
> ---
>
> Note: This will need to be rebased as comments on KVM PSCI 0.2 support
> are addressed. This patch effectively includes my comments.
>
>  hw/arm/virt.c | 42 ++++++++++++++++++------------------------
>  1 file changed, 18 insertions(+), 24 deletions(-)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 9f28c12..d8ab88d 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -181,21 +181,22 @@ static void create_fdt(VirtBoardInfo *vbi)
>                                  "clk24mhz");
>      qemu_fdt_setprop_cell(fdt, "/apb-pclk", "phandle", vbi->clock_phandle);
>
> -    /* No PSCI for TCG yet */
> -    if (kvm_enabled()) {
> -        qemu_fdt_add_subnode(fdt, "/psci");
> -        if (kvm_check_extension(kvm_state, KVM_CAP_ARM_PSCI_0_2)) {
> -            qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci-0.2");
> -        } else {
> -            qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci");
> -            qemu_fdt_setprop_cell(fdt, "/psci", "cpu_suspend",
> -                                  PSCI_FN_CPU_SUSPEND);
> -            qemu_fdt_setprop_cell(fdt, "/psci", "cpu_off", PSCI_FN_CPU_OFF);
> -            qemu_fdt_setprop_cell(fdt, "/psci", "cpu_on", PSCI_FN_CPU_ON);
> -            qemu_fdt_setprop_cell(fdt, "/psci", "migrate", PSCI_FN_MIGRATE);
> -        }
> -        qemu_fdt_setprop_string(fdt, "/psci", "method", "hvc");
> +    qemu_fdt_add_subnode(fdt, "/psci");
> +    qemu_fdt_setprop_string(fdt, "/psci", "method", "hvc");
> +    if (kvm_enabled() && !kvm_check_extension(kvm_state, KVM_CAP_ARM_PSCI_0_2)) {
> +        qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci");
> +    } else {
> +        const char compat[] = "arm,psci-0.2\0arm,psci";
> +        qemu_fdt_setprop(fdt, "/psci", "compatible", compat, sizeof(compat));
>      }

My suggestion to Pranav was that we abstract away the "which PSCI
version?" decision into a field in ARMCPU, in which case we can
just have TCG always set it to 0.2. So some of this logic
will get a little simpler on rebase.

thanks
-- PMM