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 <asm/sbi.h>
13#include <asm/kvm_vcpu_timer.h>
14#include <asm/kvm_vcpu_sbi.h>
15
16static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
17 struct kvm_vcpu_sbi_return *retdata)
18{
19 ulong hmask;
20 int i, ret = 0;
21 u64 next_cycle;
22 struct kvm_vcpu *rvcpu;
23 struct kvm *kvm = vcpu->kvm;
24 struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
25 struct kvm_cpu_trap *utrap = retdata->utrap;
26
27 switch (cp->a7) {
28 case SBI_EXT_0_1_CONSOLE_GETCHAR:
29 case SBI_EXT_0_1_CONSOLE_PUTCHAR:
30 /*
31 * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be
32 * handled in kernel so we forward these to user-space
33 */
34 kvm_riscv_vcpu_sbi_forward(vcpu, run);
35 retdata->uexit = true;
36 break;
37 case SBI_EXT_0_1_SET_TIMER:
38#if __riscv_xlen == 32
39 next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0;
40#else
41 next_cycle = (u64)cp->a0;
42#endif
43 ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle);
44 break;
45 case SBI_EXT_0_1_CLEAR_IPI:
46 ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT);
47 break;
48 case SBI_EXT_0_1_SEND_IPI:
49 if (cp->a0)
50 hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, utrap);
51 else
52 hmask = (1UL << atomic_read(v: &kvm->online_vcpus)) - 1;
53 if (utrap->scause)
54 break;
55
56 for_each_set_bit(i, &hmask, BITS_PER_LONG) {
57 rvcpu = kvm_get_vcpu_by_id(kvm: vcpu->kvm, id: i);
58 ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT);
59 if (ret < 0)
60 break;
61 }
62 break;
63 case SBI_EXT_0_1_SHUTDOWN:
64 kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
65 KVM_SYSTEM_EVENT_SHUTDOWN, 0);
66 retdata->uexit = true;
67 break;
68 case SBI_EXT_0_1_REMOTE_FENCE_I:
69 case SBI_EXT_0_1_REMOTE_SFENCE_VMA:
70 case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID:
71 if (cp->a0)
72 hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, utrap);
73 else
74 hmask = (1UL << atomic_read(v: &kvm->online_vcpus)) - 1;
75 if (utrap->scause)
76 break;
77
78 if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I)
79 kvm_riscv_fence_i(vcpu->kvm, 0, hmask);
80 else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) {
81 if (cp->a1 == 0 && cp->a2 == 0)
82 kvm_riscv_hfence_vvma_all(vcpu->kvm,
83 0, hmask);
84 else
85 kvm_riscv_hfence_vvma_gva(vcpu->kvm,
86 0, hmask,
87 cp->a1, cp->a2,
88 PAGE_SHIFT);
89 } else {
90 if (cp->a1 == 0 && cp->a2 == 0)
91 kvm_riscv_hfence_vvma_asid_all(vcpu->kvm,
92 0, hmask,
93 cp->a3);
94 else
95 kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm,
96 0, hmask,
97 cp->a1, cp->a2,
98 PAGE_SHIFT,
99 cp->a3);
100 }
101 break;
102 default:
103 retdata->err_val = SBI_ERR_NOT_SUPPORTED;
104 break;
105 }
106
107 return ret;
108}
109
110const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
111 .extid_start = SBI_EXT_0_1_SET_TIMER,
112 .extid_end = SBI_EXT_0_1_SHUTDOWN,
113 .handler = kvm_sbi_ext_v01_handler,
114};
115

source code of linux/arch/riscv/kvm/vcpu_sbi_v01.c