On 2025/12/30 9:03, Mohamed Mediouni wrote:
> Code taken from HVF and adapted for WHPX use. Note that WHPX doesn't
> have a default vs maximum IPA distinction.
>
> Signed-off-by: Mohamed Mediouni <mohamed@unpredictable.fr>
>
> Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
> ---
> hw/arm/virt.c | 32 ++++++++++++++++++++++++++
> include/hw/core/boards.h | 1 +
> target/arm/whpx/meson.build | 2 ++
> target/arm/whpx/whpx-all.c | 45 +++++++++++++++++++++++++++++++++++++
> target/arm/whpx/whpx-stub.c | 15 +++++++++++++
> target/arm/whpx_arm.h | 16 +++++++++++++
Better named as "whpx-arm.h" for consistency.
> 6 files changed, 111 insertions(+)
> create mode 100644 target/arm/whpx/whpx-stub.c
> create mode 100644 target/arm/whpx_arm.h
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 01fc1f9ac9..86d725cc76 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -72,6 +72,7 @@
> #include "hw/core/irq.h"
> #include "kvm_arm.h"
> #include "hvf_arm.h"
> +#include "whpx_arm.h"
> #include "hw/firmware/smbios.h"
> #include "qapi/visitor.h"
> #include "qapi/qapi-visit-common.h"
> @@ -3315,6 +3316,36 @@ static int virt_kvm_type(MachineState *ms, const char *type_str)
> return fixed_ipa ? 0 : requested_pa_size;
> }
>
> +static int virt_whpx_get_physical_address_range(MachineState *ms)
> +{
> + VirtMachineState *vms = VIRT_MACHINE(ms);
> +
> + int max_ipa_size = whpx_arm_get_ipa_bit_size();
> +
> + /* We freeze the memory map to compute the highest gpa */
> + virt_set_memmap(vms, max_ipa_size);
> +
> + int requested_ipa_size = 64 - clz64(vms->highest_gpa);
> +
> + /*
> + * If we're <= the default IPA size just use the default.
> + * If we're above the default but below the maximum, round up to
> + * the maximum. hvf_arm_get_max_ipa_bit_size() conveniently only
This comment still mentions "hvf" though this is imported to whpx now.
> + * returns values that are valid ARM PARange values.
> + */
> + if (requested_ipa_size <= max_ipa_size) {
> + requested_ipa_size = max_ipa_size;
> + } else {
> + error_report("-m and ,maxmem option values "
> + "require an IPA range (%d bits) larger than "
> + "the one supported by the host (%d bits)",
> + requested_ipa_size, max_ipa_size);
> + return -1;
> + }
> +
> + return requested_ipa_size;
> +}
> +
> static int virt_hvf_get_physical_address_range(MachineState *ms)
> {
> VirtMachineState *vms = VIRT_MACHINE(ms);
> @@ -3414,6 +3445,7 @@ static void virt_machine_class_init(ObjectClass *oc, const void *data)
> mc->get_default_cpu_node_id = virt_get_default_cpu_node_id;
> mc->kvm_type = virt_kvm_type;
> mc->hvf_get_physical_address_range = virt_hvf_get_physical_address_range;
> + mc->whpx_get_physical_address_range = virt_whpx_get_physical_address_range;
> assert(!mc->get_hotplug_handler);
> mc->get_hotplug_handler = virt_machine_get_hotplug_handler;
> hc->pre_plug = virt_machine_device_pre_plug_cb;
> diff --git a/include/hw/core/boards.h b/include/hw/core/boards.h
> index 815845207b..0dd9ef2613 100644
> --- a/include/hw/core/boards.h
> +++ b/include/hw/core/boards.h
> @@ -278,6 +278,7 @@ struct MachineClass {
> void (*wakeup)(MachineState *state);
> int (*kvm_type)(MachineState *machine, const char *arg);
> int (*hvf_get_physical_address_range)(MachineState *machine);
> + int (*whpx_get_physical_address_range)(MachineState *machine);
>
> BlockInterfaceType block_default_type;
> int units_per_default_bus;
> diff --git a/target/arm/whpx/meson.build b/target/arm/whpx/meson.build
> index 1de2ef0283..3df632c9d3 100644
> --- a/target/arm/whpx/meson.build
> +++ b/target/arm/whpx/meson.build
> @@ -1,3 +1,5 @@
> arm_system_ss.add(when: 'CONFIG_WHPX', if_true: files(
> 'whpx-all.c',
> ))
> +
> +arm_common_system_ss.add(when: 'CONFIG_WHPX', if_false: files('whpx-stub.c'))
> diff --git a/target/arm/whpx/whpx-all.c b/target/arm/whpx/whpx-all.c
> index 75b82be4e7..fe58217e46 100644
> --- a/target/arm/whpx/whpx-all.c
> +++ b/target/arm/whpx/whpx-all.c
> @@ -35,6 +35,7 @@
> #include "system/whpx-accel-ops.h"
> #include "system/whpx-all.h"
> #include "system/whpx-common.h"
> +#include "whpx_arm.h"
> #include "hw/arm/bsa.h"
> #include "arm-powerctl.h"
>
> @@ -657,6 +658,40 @@ static void whpx_cpu_update_state(void *opaque, bool running, RunState state)
> {
> }
>
> +uint32_t whpx_arm_get_ipa_bit_size(void)
> +{
> + WHV_CAPABILITY whpx_cap;
> + UINT32 whpx_cap_size;
> + HRESULT hr;
> + hr = whp_dispatch.WHvGetCapability(
> + WHvCapabilityCodePhysicalAddressWidth, &whpx_cap,
> + sizeof(whpx_cap), &whpx_cap_size);
> + if (FAILED(hr)) {
> + error_report("WHPX: failed to get supported"
> + "physical address width, hr=%08lx", hr);
> + }
> +
> + /*
> + * We clamp any IPA size we want to back the VM with to a valid PARange
> + * value so the guest doesn't try and map memory outside of the valid range.
> + * This logic just clamps the passed in IPA bit size to the first valid
> + * PARange value <= to it.
> + */
> + return round_down_to_parange_bit_size(whpx_cap.PhysicalAddressWidth);
> +}
> +
> +static void clamp_id_aa64mmfr0_parange_to_ipa_size(ARMISARegisters *isar)
> +{
> + uint32_t ipa_size = whpx_arm_get_ipa_bit_size();
> + uint64_t id_aa64mmfr0;
> +
> + /* Clamp down the PARange to the IPA size the kernel supports. */
> + uint8_t index = round_down_to_parange_index(ipa_size);
> + id_aa64mmfr0 = GET_IDREG(isar, ID_AA64MMFR0);
> + id_aa64mmfr0 = (id_aa64mmfr0 & ~R_ID_AA64MMFR0_PARANGE_MASK) | index;
> + SET_IDREG(isar, ID_AA64MMFR0, id_aa64mmfr0);
> +}
> +
> int whpx_init_vcpu(CPUState *cpu)
> {
> HRESULT hr;
> @@ -735,6 +770,7 @@ int whpx_init_vcpu(CPUState *cpu)
> val.Reg64 = deposit64(arm_cpu->mp_affinity, 31, 1, 1 /* RES1 */);
> whpx_set_reg(cpu, WHvArm64RegisterMpidrEl1, val);
>
> + clamp_id_aa64mmfr0_parange_to_ipa_size(&arm_cpu->isar);
> return 0;
>
> error:
> @@ -757,6 +793,8 @@ int whpx_accel_init(AccelState *as, MachineState *ms)
> UINT32 whpx_cap_size;
> WHV_PARTITION_PROPERTY prop;
> WHV_CAPABILITY_FEATURES features = {0};
> + MachineClass *mc = MACHINE_GET_CLASS(ms);
> + int pa_range = 0;
>
> whpx = &whpx_global;
> /* on arm64 Windows Hypervisor Platform, vGICv3 always used */
> @@ -767,6 +805,13 @@ int whpx_accel_init(AccelState *as, MachineState *ms)
> goto error;
> }
>
> + if (mc->whpx_get_physical_address_range) {
> + pa_range = mc->whpx_get_physical_address_range(ms);
> + if (pa_range < 0) {
> + return -EINVAL;
This should: goto error;
> + }
> + }
> +
> whpx->mem_quota = ms->ram_size;
>
> hr = whp_dispatch.WHvGetCapability(
> diff --git a/target/arm/whpx/whpx-stub.c b/target/arm/whpx/whpx-stub.c
> new file mode 100644
> index 0000000000..32e434a5f6
> --- /dev/null
> +++ b/target/arm/whpx/whpx-stub.c
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * WHPX stubs for ARM
> + *
> + * Copyright (c) 2025 Mohamed Mediouni
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +#include "whpx_arm.h"
> +
> +uint32_t whpx_arm_get_ipa_bit_size(void)
> +{
> + g_assert_not_reached();
> +}
> diff --git a/target/arm/whpx_arm.h b/target/arm/whpx_arm.h
> new file mode 100644
> index 0000000000..de7406b66f
> --- /dev/null
> +++ b/target/arm/whpx_arm.h
> @@ -0,0 +1,16 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * WHPX support -- ARM specifics
> + *
> + * Copyright (c) 2025 Mohamed Mediouni
> + *
> + */
> +
> +#ifndef QEMU_WHPX_ARM_H
> +#define QEMU_WHPX_ARM_H
> +
> +#include "target/arm/cpu-qom.h"
> +
> +uint32_t whpx_arm_get_ipa_bit_size(void);
> +
> +#endif