Hi Shameer,
On 8/1/25 9:47 AM, Shameer Kolothum wrote:
> From: Shameer Kolothum <[email protected]>
>
> Introduce a QAPI‐defined struct (and its array) for target implementation
> CPUs. This enables specifying target implementation CPU parameters
> via -machine, for example:
>
> -M virt, \
> impl-cpu.0.midr=1,impl-cpu.0.revidr=1,impl-cpu.0.aidr=1, \
> impl-cpu.1.midr=2,impl-cpu.1.revidr=2,impl-cpu.1.aidr=0
>
> Subsequent patch will make use of this by using object_property_add(),
> allowing users to configure each target CPU’s midr, revidr, and aidr
> fields directly from the command line.
>
> While at it, also provide a helper function to set the target CPUs.
>
> Signed-off-by: Shameer Kolothum <[email protected]>
> ---
> qapi/machine.json | 34 ++++++++++++++++++++++++++++++++++
> target/arm/kvm.c | 16 ++++++++++++++++
> target/arm/kvm_arm.h | 8 ++++++++
> 3 files changed, 58 insertions(+)
>
> diff --git a/qapi/machine.json b/qapi/machine.json
> index a6b8795b09..d6e0e3b2e3 100644
> --- a/qapi/machine.json
> +++ b/qapi/machine.json
> @@ -1898,3 +1898,37 @@
> { 'command': 'x-query-interrupt-controllers',
> 'returns': 'HumanReadableText',
> 'features': [ 'unstable' ]}
> +
> +##
> +# @ArmTargetImplCPU:
> +#
> +# Info for a single target implementation CPU.
> +#
> +# @midr: MIDR value
> +# @revidr: REVIDR value
> +# @aidr: AIDR value
> +#
> +# Since: 10.2
> +##
> +{ 'struct': 'ArmTargetImplCPU',
> + 'data': {
> + 'midr': 'uint64',
> + 'revidr': 'uint64',
> + 'aidr': 'uint64'
> + }
> +}
> +
> +##
> +# @ArmTargetImplCPUs:
> +#
> +# List of target implementation CPUs.
> +#
> +# @target-cpus: List of ArmTargetImplCPU entries.
> +#
> +# Since: 10.2
> +##
> +{ 'struct': 'ArmTargetImplCPUs',
> + 'data': {
> + 'target-cpus': ['ArmTargetImplCPU']
> + }
> +}
> diff --git a/target/arm/kvm.c b/target/arm/kvm.c
> index eb04640b50..8f325c4ca4 100644
> --- a/target/arm/kvm.c
> +++ b/target/arm/kvm.c
> @@ -66,6 +66,9 @@ typedef struct ARMHostCPUFeatures {
>
> static ARMHostCPUFeatures arm_host_cpu_features;
>
> +static uint64_t target_impl_cpus_num;
> +static ArmTargetImplCPU *target_impl_cpus;
> +
> /**
> * kvm_arm_vcpu_init:
> * @cpu: ARMCPU
> @@ -2816,3 +2819,16 @@ void kvm_arm_enable_mte(Object *cpuobj, Error **errp)
> cpu->kvm_mte = true;
> }
> }
> +
> +bool kvm_arm_set_target_impl_cpus(uint64_t num, ArmTargetImplCPU *cpus)
> +{
> +
> + if (target_impl_cpus_num) {
> + return false;
> + }
> +
> + target_impl_cpus_num = num;
> + target_impl_cpus = cpus;
see my question on 4/4 wrt array.
Eric
> +
> + return true;
> +}
> diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
> index 3cd6447901..8754302333 100644
> --- a/target/arm/kvm_arm.h
> +++ b/target/arm/kvm_arm.h
> @@ -244,6 +244,8 @@ void kvm_arm_enable_mte(Object *cpuobj, Error **errp);
>
> int kvm_arm_get_writable_id_regs(ARMCPU *cpu, IdRegMap *idregmap);
>
> +bool kvm_arm_set_target_impl_cpus(uint64_t num, ArmTargetImplCPU *cpus);
> +
> #else
>
> /*
> @@ -280,6 +282,12 @@ static inline int kvm_arm_get_writable_id_regs(ARMCPU
> *cpu, IdRegMap *idregmap)
> return -ENOSYS;
> }
>
> +static inline
> +bool kvm_arm_set_target_impl_cpus(uint64_t num, ArmTargetImplCPU *cpus)
> +{
> + return false;
> +}
> +
> /*
> * These functions should never actually be called without KVM support.
> */
