blob: f96991d230bfc33fe2eef7de81e89a6791c96e76 [file] [log] [blame]
// 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/sbi.h>
#include <asm/kvm_vcpu_sbi.h>
static int kvm_linux_err_map_sbi(int err)
{
switch (err) {
case 0:
return SBI_SUCCESS;
case -EPERM:
return SBI_ERR_DENIED;
case -EINVAL:
return SBI_ERR_INVALID_PARAM;
case -EFAULT:
return SBI_ERR_INVALID_ADDRESS;
case -EOPNOTSUPP:
return SBI_ERR_NOT_SUPPORTED;
case -EALREADY:
return SBI_ERR_ALREADY_AVAILABLE;
default:
return SBI_ERR_FAILURE;
};
}
#ifndef CONFIG_RISCV_SBI_V01
static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
.extid_start = -1UL,
.extid_end = -1UL,
.handler = NULL,
};
#endif
static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
&vcpu_sbi_ext_v01,
&vcpu_sbi_ext_base,
&vcpu_sbi_ext_time,
&vcpu_sbi_ext_ipi,
&vcpu_sbi_ext_rfence,
&vcpu_sbi_ext_srst,
&vcpu_sbi_ext_hsm,
&vcpu_sbi_ext_experimental,
&vcpu_sbi_ext_vendor,
};
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;
}
void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu,
struct kvm_run *run,
u32 type, u64 reason)
{
unsigned long 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->system_event.ndata = 1;
run->system_event.data[0] = reason;
run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
}
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;
}
const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid)
{
int i = 0;
for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) {
if (sbi_ext[i]->extid_start <= extid &&
sbi_ext[i]->extid_end >= extid)
return sbi_ext[i];
}
return NULL;
}
int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
int ret = 1;
bool next_sepc = true;
bool userspace_exit = false;
struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
const struct kvm_vcpu_sbi_extension *sbi_ext;
struct kvm_cpu_trap utrap = { 0 };
unsigned long out_val = 0;
bool ext_is_v01 = false;
sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7);
if (sbi_ext && sbi_ext->handler) {
#ifdef CONFIG_RISCV_SBI_V01
if (cp->a7 >= SBI_EXT_0_1_SET_TIMER &&
cp->a7 <= SBI_EXT_0_1_SHUTDOWN)
ext_is_v01 = true;
#endif
ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit);
} else {
/* Return error for unsupported SBI calls */
cp->a0 = SBI_ERR_NOT_SUPPORTED;
goto ecall_done;
}
/* Handle special error cases i.e trap, exit or userspace forward */
if (utrap.scause) {
/* No need to increment sepc or exit ioctl loop */
ret = 1;
utrap.sepc = cp->sepc;
kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
next_sepc = false;
goto ecall_done;
}
/* Exit ioctl loop or Propagate the error code the guest */
if (userspace_exit) {
next_sepc = false;
ret = 0;
} else {
/**
* SBI extension handler always returns an Linux error code. Convert
* it to the SBI specific error code that can be propagated the SBI
* caller.
*/
ret = kvm_linux_err_map_sbi(ret);
cp->a0 = ret;
ret = 1;
}
ecall_done:
if (next_sepc)
cp->sepc += 4;
if (!ext_is_v01)
cp->a1 = out_val;
return ret;
}