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
16 static 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 kvm_riscv_vcpu_sbi_forward(vcpu, run);
45 retdata->uexit = true;
46 } else {
47 sbi_ext = kvm_vcpu_sbi_find_ext(vcpu, cp->a0);
48 *out_val = sbi_ext && sbi_ext->probe ?
49 sbi_ext->probe(vcpu) : !!sbi_ext;
50 }
51 break;
52 case SBI_EXT_BASE_GET_MVENDORID:
53 *out_val = vcpu->arch.mvendorid;
54 break;
55 case SBI_EXT_BASE_GET_MARCHID:
56 *out_val = vcpu->arch.marchid;
57 break;
58 case SBI_EXT_BASE_GET_MIMPID:
59 *out_val = vcpu->arch.mimpid;
60 break;
61 default:
62 retdata->err_val = SBI_ERR_NOT_SUPPORTED;
63 break;
64 }
65
66 return 0;
67 }
68
69 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_base = {
70 .extid_start = SBI_EXT_BASE,
71 .extid_end = SBI_EXT_BASE,
72 .handler = kvm_sbi_ext_base_handler,
73 };
74
75 static int kvm_sbi_ext_forward_handler(struct kvm_vcpu *vcpu,
76 struct kvm_run *run,
77 struct kvm_vcpu_sbi_return *retdata)
78 {
79 /*
80 * Both SBI experimental and vendor extensions are
81 * unconditionally forwarded to userspace.
82 */
83 kvm_riscv_vcpu_sbi_forward(vcpu, run);
84 retdata->uexit = true;
85 return 0;
86 }
87
88 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental = {
89 .extid_start = SBI_EXT_EXPERIMENTAL_START,
90 .extid_end = SBI_EXT_EXPERIMENTAL_END,
91 .handler = kvm_sbi_ext_forward_handler,
92 };
93
94 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor = {
95 .extid_start = SBI_EXT_VENDOR_START,
96 .extid_end = SBI_EXT_VENDOR_END,
97 .handler = kvm_sbi_ext_forward_handler,
98 };
99
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.