diff options
Diffstat (limited to 'arch/riscv/kvm/vcpu_sbi_hsm.c')
| -rw-r--r-- | arch/riscv/kvm/vcpu_sbi_hsm.c | 119 |
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, +}; |