| // 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/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; |
| int ret = 0; |
| |
| target_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, target_vcpuid); |
| if (!target_vcpu) |
| return SBI_ERR_INVALID_PARAM; |
| |
| spin_lock(&target_vcpu->arch.mp_state_lock); |
| |
| if (!kvm_riscv_vcpu_stopped(target_vcpu)) { |
| ret = SBI_ERR_ALREADY_AVAILABLE; |
| goto out; |
| } |
| |
| spin_lock(&target_vcpu->arch.reset_cntx_lock); |
| 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; |
| spin_unlock(&target_vcpu->arch.reset_cntx_lock); |
| |
| kvm_make_request(KVM_REQ_VCPU_RESET, target_vcpu); |
| |
| __kvm_riscv_vcpu_power_on(target_vcpu); |
| |
| out: |
| spin_unlock(&target_vcpu->arch.mp_state_lock); |
| |
| return ret; |
| } |
| |
| static int kvm_sbi_hsm_vcpu_stop(struct kvm_vcpu *vcpu) |
| { |
| int ret = 0; |
| |
| spin_lock(&vcpu->arch.mp_state_lock); |
| |
| if (kvm_riscv_vcpu_stopped(vcpu)) { |
| ret = SBI_ERR_FAILURE; |
| goto out; |
| } |
| |
| __kvm_riscv_vcpu_power_off(vcpu); |
| |
| out: |
| spin_unlock(&vcpu->arch.mp_state_lock); |
| |
| return ret; |
| } |
| |
| 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 SBI_ERR_INVALID_PARAM; |
| if (!kvm_riscv_vcpu_stopped(target_vcpu)) |
| 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, |
| struct kvm_vcpu_sbi_return *retdata) |
| { |
| int ret = 0; |
| struct kvm_cpu_context *cp = &vcpu->arch.guest_context; |
| unsigned long funcid = cp->a6; |
| |
| switch (funcid) { |
| case SBI_EXT_HSM_HART_START: |
| ret = kvm_sbi_hsm_vcpu_start(vcpu); |
| 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) { |
| retdata->out_val = ret; |
| retdata->err_val = 0; |
| } |
| return 0; |
| 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 = SBI_ERR_NOT_SUPPORTED; |
| break; |
| default: |
| ret = SBI_ERR_INVALID_PARAM; |
| } |
| break; |
| default: |
| ret = SBI_ERR_NOT_SUPPORTED; |
| } |
| |
| retdata->err_val = ret; |
| |
| return 0; |
| } |
| |
| 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, |
| }; |