xref: /openbmc/linux/arch/riscv/kvm/vcpu_sbi_base.c (revision c62a76859723fb732bfeda847f22192e24e121a7)
1*c62a7685SAtish Patra // SPDX-License-Identifier: GPL-2.0
2*c62a7685SAtish Patra /*
3*c62a7685SAtish Patra  * Copyright (c) 2021 Western Digital Corporation or its affiliates.
4*c62a7685SAtish Patra  *
5*c62a7685SAtish Patra  * Authors:
6*c62a7685SAtish Patra  *     Atish Patra <atish.patra@wdc.com>
7*c62a7685SAtish Patra  */
8*c62a7685SAtish Patra 
9*c62a7685SAtish Patra #include <linux/errno.h>
10*c62a7685SAtish Patra #include <linux/err.h>
11*c62a7685SAtish Patra #include <linux/kvm_host.h>
12*c62a7685SAtish Patra #include <asm/csr.h>
13*c62a7685SAtish Patra #include <asm/sbi.h>
14*c62a7685SAtish Patra #include <asm/kvm_vcpu_timer.h>
15*c62a7685SAtish Patra #include <asm/kvm_vcpu_sbi.h>
16*c62a7685SAtish Patra 
17*c62a7685SAtish Patra static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
18*c62a7685SAtish Patra 				    unsigned long *out_val,
19*c62a7685SAtish Patra 				    struct kvm_cpu_trap *trap, bool *exit)
20*c62a7685SAtish Patra {
21*c62a7685SAtish Patra 	int ret = 0;
22*c62a7685SAtish Patra 	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
23*c62a7685SAtish Patra 	struct sbiret ecall_ret;
24*c62a7685SAtish Patra 
25*c62a7685SAtish Patra 	switch (cp->a6) {
26*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_SPEC_VERSION:
27*c62a7685SAtish Patra 		*out_val = (KVM_SBI_VERSION_MAJOR <<
28*c62a7685SAtish Patra 			    SBI_SPEC_VERSION_MAJOR_SHIFT) |
29*c62a7685SAtish Patra 			    KVM_SBI_VERSION_MINOR;
30*c62a7685SAtish Patra 		break;
31*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_IMP_ID:
32*c62a7685SAtish Patra 		*out_val = KVM_SBI_IMPID;
33*c62a7685SAtish Patra 		break;
34*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_IMP_VERSION:
35*c62a7685SAtish Patra 		*out_val = 0;
36*c62a7685SAtish Patra 		break;
37*c62a7685SAtish Patra 	case SBI_EXT_BASE_PROBE_EXT:
38*c62a7685SAtish Patra 		if ((cp->a0 >= SBI_EXT_EXPERIMENTAL_START &&
39*c62a7685SAtish Patra 		     cp->a0 <= SBI_EXT_EXPERIMENTAL_END) ||
40*c62a7685SAtish Patra 		    (cp->a0 >= SBI_EXT_VENDOR_START &&
41*c62a7685SAtish Patra 		     cp->a0 <= SBI_EXT_VENDOR_END)) {
42*c62a7685SAtish Patra 			/*
43*c62a7685SAtish Patra 			 * For experimental/vendor extensions
44*c62a7685SAtish Patra 			 * forward it to the userspace
45*c62a7685SAtish Patra 			 */
46*c62a7685SAtish Patra 			kvm_riscv_vcpu_sbi_forward(vcpu, run);
47*c62a7685SAtish Patra 			*exit = true;
48*c62a7685SAtish Patra 		} else
49*c62a7685SAtish Patra 			*out_val = kvm_vcpu_sbi_find_ext(cp->a0) ? 1 : 0;
50*c62a7685SAtish Patra 		break;
51*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_MVENDORID:
52*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_MARCHID:
53*c62a7685SAtish Patra 	case SBI_EXT_BASE_GET_MIMPID:
54*c62a7685SAtish Patra 		ecall_ret = sbi_ecall(SBI_EXT_BASE, cp->a6, 0, 0, 0, 0, 0, 0);
55*c62a7685SAtish Patra 		if (!ecall_ret.error)
56*c62a7685SAtish Patra 			*out_val = ecall_ret.value;
57*c62a7685SAtish Patra 		/*TODO: We are unnecessarily converting the error twice */
58*c62a7685SAtish Patra 		ret = sbi_err_map_linux_errno(ecall_ret.error);
59*c62a7685SAtish Patra 		break;
60*c62a7685SAtish Patra 	default:
61*c62a7685SAtish Patra 		ret = -EOPNOTSUPP;
62*c62a7685SAtish Patra 		break;
63*c62a7685SAtish Patra 	}
64*c62a7685SAtish Patra 
65*c62a7685SAtish Patra 	return ret;
66*c62a7685SAtish Patra }
67*c62a7685SAtish Patra 
68*c62a7685SAtish Patra const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base = {
69*c62a7685SAtish Patra 	.extid_start = SBI_EXT_BASE,
70*c62a7685SAtish Patra 	.extid_end = SBI_EXT_BASE,
71*c62a7685SAtish Patra 	.handler = kvm_sbi_ext_base_handler,
72*c62a7685SAtish Patra };
73