On Mon, 27 Oct 2025, Peter Maydell wrote:
On Thu, 11 Sept 2025 at 15:49, Sebastian Ott <[email protected]> wrote:
Provide a kvm specific vcpu property to override the default
(as of kernel v6.13 that would be PSCI v1.3) PSCI version emulated
by kvm. Current valid values are: 0.1, 0.2, 1.0, 1.1, 1.2, and 1.3
Signed-off-by: Sebastian Ott <[email protected]>
---
docs/system/arm/cpu-features.rst | 5 +++
target/arm/cpu.h | 6 +++
target/arm/kvm.c | 70 +++++++++++++++++++++++++++++++-
3 files changed, 80 insertions(+), 1 deletion(-)
diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-features.rst
index 37d5dfd15b..1d32ce0fee 100644
--- a/docs/system/arm/cpu-features.rst
+++ b/docs/system/arm/cpu-features.rst
@@ -204,6 +204,11 @@ the list of KVM VCPU features and their descriptions.
the guest scheduler behavior and/or be exposed to the guest
userspace.
+``kvm-psci-version``
+ Override the default (as of kernel v6.13 that would be PSCI v1.3)
+ PSCI version emulated by the kernel. Current valid values are:
+ 0.1, 0.2, 1.0, 1.1, 1.2, and 1.3
+
TCG VCPU Features
=================
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index c15d79a106..44292aab32 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -974,6 +974,12 @@ struct ArchCPU {
*/
uint32_t psci_version;
+ /*
+ * Intermediate value used during property parsing.
+ * Once finalized, the value should be read from psci_version.
+ */
+ uint32_t prop_psci_version;
+
/* Current power state, access guarded by BQL */
ARMPSCIState power_state;
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 6672344855..bc6073f395 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -483,6 +483,59 @@ static void kvm_steal_time_set(Object *obj, bool value,
Error **errp)
ARM_CPU(obj)->kvm_steal_time = value ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
}
+static char *kvm_get_psci_version(Object *obj, Error **errp)
+{
+ ARMCPU *cpu = ARM_CPU(obj);
+ const char *val;
+
+ switch (cpu->prop_psci_version) {
+ case QEMU_PSCI_VERSION_0_1:
+ val = "0.1";
+ break;
+ case QEMU_PSCI_VERSION_0_2:
+ val = "0.2";
+ break;
+ case QEMU_PSCI_VERSION_1_0:
+ val = "1.0";
+ break;
+ case QEMU_PSCI_VERSION_1_1:
+ val = "1.1";
+ break;
+ case QEMU_PSCI_VERSION_1_2:
+ val = "1.2";
+ break;
+ case QEMU_PSCI_VERSION_1_3:
+ val = "1.3";
+ break;
+ default:
+ val = "0.2";
+ break;
+ }
+ return g_strdup(val);
+}
+
+static void kvm_set_psci_version(Object *obj, const char *value, Error **errp)
+{
+ ARMCPU *cpu = ARM_CPU(obj);
+
+ if (!strcmp(value, "0.1")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_0_1;
+ } else if (!strcmp(value, "0.2")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_0_2;
+ } else if (!strcmp(value, "1.0")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_1_0;
+ } else if (!strcmp(value, "1.1")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_1_1;
+ } else if (!strcmp(value, "1.2")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_1_2;
+ } else if (!strcmp(value, "1.3")) {
+ cpu->prop_psci_version = QEMU_PSCI_VERSION_1_3;
We already have six values here and it's not implausible
we might end up with more in future; maybe we should make the
mapping between string and constant data-driven rather
than having code written out longhand in the get and set
functions?
Yes, sure. I'll send out a V2.
Thanks!
Sebastian
