[PATCH 08/16] ARM/ARM64: KVM: Emulate PSCI v0.2 AFFINITY_INFO

Christoffer Dall
2014-05-25T18:19:27Z

From: Anup Patel <anup.patel@linaro.org>

This patch adds emulation of PSCI v0.2 AFFINITY_INFO function call
for KVM ARM/ARM64. This is a VCPU-level function call which will be
used to determine current state of given affinity level.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
arch/arm/kvm/psci.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 50 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index 5936213..3b6a0cf 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -27,6 +27,16 @@
* as described in ARM document number ARM DEN 0022A.
*/

+#define AFFINITY_MASK(level) ~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1)
+
+static unsigned long psci_affinity_mask(unsigned long affinity_level)
+{
+ if (affinity_level <= 3)
+ return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level);
+
+ return 0;
+}
+
static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
{
vcpu->arch.pause = true;
@@ -85,6 +95,42 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
return PSCI_RET_SUCCESS;
}

+static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu)
+{
+ int i;
+ unsigned long mpidr;
+ unsigned long target_affinity;
+ unsigned long target_affinity_mask;
+ unsigned long lowest_affinity_level;
+ struct kvm *kvm = vcpu->kvm;
+ struct kvm_vcpu *tmp;
+
+ target_affinity = *vcpu_reg(vcpu, 1);
+ lowest_affinity_level = *vcpu_reg(vcpu, 2);
+
+ /* Determine target affinity mask */
+ target_affinity_mask = psci_affinity_mask(lowest_affinity_level);
+ if (!target_affinity_mask)
+ return PSCI_RET_INVALID_PARAMS;
+
+ /* Ignore other bits of target affinity */
+ target_affinity &= target_affinity_mask;
+
+ /*
+ * If one or more VCPU matching target affinity are running
+ * then ON else OFF
+ */
+ kvm_for_each_vcpu(i, tmp, kvm) {
+ mpidr = kvm_vcpu_get_mpidr(tmp);
+ if (((mpidr & target_affinity_mask) == target_affinity) &&
+ !tmp->arch.pause) {
+ return PSCI_0_2_AFFINITY_LEVEL_ON;
+ }
+ }
+
+ return PSCI_0_2_AFFINITY_LEVEL_OFF;
+}
+
static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
{
memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
@@ -132,6 +178,10 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
case PSCI_0_2_FN64_CPU_ON:
val = kvm_psci_vcpu_on(vcpu);
break;
+ case PSCI_0_2_FN_AFFINITY_INFO:
+ case PSCI_0_2_FN64_AFFINITY_INFO:
+ val = kvm_psci_vcpu_affinity_info(vcpu);
+ break;
case PSCI_0_2_FN_SYSTEM_OFF:
kvm_psci_system_off(vcpu);
/*
@@ -157,12 +207,10 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
ret = 0;
break;
case PSCI_0_2_FN_CPU_SUSPEND:
- case PSCI_0_2_FN_AFFINITY_INFO:
case PSCI_0_2_FN_MIGRATE:
case PSCI_0_2_FN_MIGRATE_INFO_TYPE:
case PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
case PSCI_0_2_FN64_CPU_SUSPEND:
- case PSCI_0_2_FN64_AFFINITY_INFO:
case PSCI_0_2_FN64_MIGRATE:
case PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
val = PSCI_RET_NOT_SUPPORTED;
--
1.8.5.2