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Diffstat (limited to 'arch/riscv/kvm/vcpu_sbi_hsm.c')
-rw-r--r--arch/riscv/kvm/vcpu_sbi_hsm.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu_sbi_hsm.c b/arch/riscv/kvm/vcpu_sbi_hsm.c
new file mode 100644
index 000000000..239dec0a6
--- /dev/null
+++ b/arch/riscv/kvm/vcpu_sbi_hsm.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ * Atish Patra <atish.patra@wdc.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kvm_host.h>
+#include <asm/csr.h>
+#include <asm/sbi.h>
+#include <asm/kvm_vcpu_sbi.h>
+
+static int kvm_sbi_hsm_vcpu_start(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpu_context *reset_cntx;
+ struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
+ struct kvm_vcpu *target_vcpu;
+ unsigned long target_vcpuid = cp->a0;
+
+ target_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, target_vcpuid);
+ if (!target_vcpu)
+ return -EINVAL;
+ if (!target_vcpu->arch.power_off)
+ return -EALREADY;
+
+ reset_cntx = &target_vcpu->arch.guest_reset_context;
+ /* start address */
+ reset_cntx->sepc = cp->a1;
+ /* target vcpu id to start */
+ reset_cntx->a0 = target_vcpuid;
+ /* private data passed from kernel */
+ reset_cntx->a1 = cp->a2;
+ kvm_make_request(KVM_REQ_VCPU_RESET, target_vcpu);
+
+ kvm_riscv_vcpu_power_on(target_vcpu);
+
+ return 0;
+}
+
+static int kvm_sbi_hsm_vcpu_stop(struct kvm_vcpu *vcpu)
+{
+ if (vcpu->arch.power_off)
+ return -EINVAL;
+
+ kvm_riscv_vcpu_power_off(vcpu);
+
+ return 0;
+}
+
+static int kvm_sbi_hsm_vcpu_get_status(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
+ unsigned long target_vcpuid = cp->a0;
+ struct kvm_vcpu *target_vcpu;
+
+ target_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, target_vcpuid);
+ if (!target_vcpu)
+ return -EINVAL;
+ if (!target_vcpu->arch.power_off)
+ return SBI_HSM_STATE_STARTED;
+ else if (vcpu->stat.generic.blocking)
+ return SBI_HSM_STATE_SUSPENDED;
+ else
+ return SBI_HSM_STATE_STOPPED;
+}
+
+static int kvm_sbi_ext_hsm_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ unsigned long *out_val,
+ struct kvm_cpu_trap *utrap,
+ bool *exit)
+{
+ int ret = 0;
+ struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
+ struct kvm *kvm = vcpu->kvm;
+ unsigned long funcid = cp->a6;
+
+ switch (funcid) {
+ case SBI_EXT_HSM_HART_START:
+ mutex_lock(&kvm->lock);
+ ret = kvm_sbi_hsm_vcpu_start(vcpu);
+ mutex_unlock(&kvm->lock);
+ break;
+ case SBI_EXT_HSM_HART_STOP:
+ ret = kvm_sbi_hsm_vcpu_stop(vcpu);
+ break;
+ case SBI_EXT_HSM_HART_STATUS:
+ ret = kvm_sbi_hsm_vcpu_get_status(vcpu);
+ if (ret >= 0) {
+ *out_val = ret;
+ ret = 0;
+ }
+ break;
+ case SBI_EXT_HSM_HART_SUSPEND:
+ switch (cp->a0) {
+ case SBI_HSM_SUSPEND_RET_DEFAULT:
+ kvm_riscv_vcpu_wfi(vcpu);
+ break;
+ case SBI_HSM_SUSPEND_NON_RET_DEFAULT:
+ ret = -EOPNOTSUPP;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ }
+
+ return ret;
+}
+
+const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm = {
+ .extid_start = SBI_EXT_HSM,
+ .extid_end = SBI_EXT_HSM,
+ .handler = kvm_sbi_ext_hsm_handler,
+};