diff options
Diffstat (limited to 'arch/riscv/kvm/vcpu_sbi.c')
| -rw-r--r-- | arch/riscv/kvm/vcpu_sbi.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c new file mode 100644 index 000000000000..ebdcdbade9c6 --- /dev/null +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -0,0 +1,185 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * Copyright (c) 2019 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_timer.h> + +#define SBI_VERSION_MAJOR 0 +#define SBI_VERSION_MINOR 1 + +static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, + struct kvm_run *run) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + vcpu->arch.sbi_context.return_handled = 0; + vcpu->stat.ecall_exit_stat++; + run->exit_reason = KVM_EXIT_RISCV_SBI; + run->riscv_sbi.extension_id = cp->a7; + run->riscv_sbi.function_id = cp->a6; + run->riscv_sbi.args[0] = cp->a0; + run->riscv_sbi.args[1] = cp->a1; + run->riscv_sbi.args[2] = cp->a2; + run->riscv_sbi.args[3] = cp->a3; + run->riscv_sbi.args[4] = cp->a4; + run->riscv_sbi.args[5] = cp->a5; + run->riscv_sbi.ret[0] = cp->a0; + run->riscv_sbi.ret[1] = cp->a1; +} + +int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + /* Handle SBI return only once */ + if (vcpu->arch.sbi_context.return_handled) + return 0; + vcpu->arch.sbi_context.return_handled = 1; + + /* Update return values */ + cp->a0 = run->riscv_sbi.ret[0]; + cp->a1 = run->riscv_sbi.ret[1]; + + /* Move to next instruction */ + vcpu->arch.guest_context.sepc += 4; + + return 0; +} + +#ifdef CONFIG_RISCV_SBI_V01 + +static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu, + struct kvm_run *run, u32 type) +{ + int i; + struct kvm_vcpu *tmp; + + kvm_for_each_vcpu(i, tmp, vcpu->kvm) + tmp->arch.power_off = true; + kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP); + + memset(&run->system_event, 0, sizeof(run->system_event)); + run->system_event.type = type; + run->exit_reason = KVM_EXIT_SYSTEM_EVENT; +} + +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + ulong hmask; + int i, ret = 1; + u64 next_cycle; + struct kvm_vcpu *rvcpu; + bool next_sepc = true; + struct cpumask cm, hm; + struct kvm *kvm = vcpu->kvm; + struct kvm_cpu_trap utrap = { 0 }; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + + if (!cp) + return -EINVAL; + + switch (cp->a7) { + case SBI_EXT_0_1_CONSOLE_GETCHAR: + case SBI_EXT_0_1_CONSOLE_PUTCHAR: + /* + * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be + * handled in kernel so we forward these to user-space + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + next_sepc = false; + ret = 0; + break; + case SBI_EXT_0_1_SET_TIMER: +#if __riscv_xlen == 32 + next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0; +#else + next_cycle = (u64)cp->a0; +#endif + kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); + break; + case SBI_EXT_0_1_CLEAR_IPI: + kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); + break; + case SBI_EXT_0_1_SEND_IPI: + if (cp->a0) + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, + &utrap); + else + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; + if (utrap.scause) { + utrap.sepc = cp->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + next_sepc = false; + break; + } + for_each_set_bit(i, &hmask, BITS_PER_LONG) { + rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); + kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); + } + break; + case SBI_EXT_0_1_SHUTDOWN: + kvm_sbi_system_shutdown(vcpu, run, KVM_SYSTEM_EVENT_SHUTDOWN); + next_sepc = false; + ret = 0; + break; + case SBI_EXT_0_1_REMOTE_FENCE_I: + case SBI_EXT_0_1_REMOTE_SFENCE_VMA: + case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID: + if (cp->a0) + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, + &utrap); + else + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; + if (utrap.scause) { + utrap.sepc = cp->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + next_sepc = false; + break; + } + cpumask_clear(&cm); + for_each_set_bit(i, &hmask, BITS_PER_LONG) { + rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); + if (rvcpu->cpu < 0) + continue; + cpumask_set_cpu(rvcpu->cpu, &cm); + } + riscv_cpuid_to_hartid_mask(&cm, &hm); + if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) + sbi_remote_fence_i(cpumask_bits(&hm)); + else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) + sbi_remote_hfence_vvma(cpumask_bits(&hm), + cp->a1, cp->a2); + else + sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), + cp->a1, cp->a2, cp->a3); + break; + default: + /* Return error for unsupported SBI calls */ + cp->a0 = SBI_ERR_NOT_SUPPORTED; + break; + }; + + if (next_sepc) + cp->sepc += 4; + + return ret; +} + +#else + +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + return 0; +} + +#endif |