vcpu_sbi_base.c

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