xref: /linux/arch/riscv/kvm/vcpu_sbi_v01.c (revision 497e6b37b0099dc415578488287fd84fb74433eb)
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 
16 static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
17 				      unsigned long *out_val,
18 				      struct kvm_cpu_trap *utrap,
19 				      bool *exit)
20 {
21 	ulong hmask;
22 	int i, ret = 0;
23 	u64 next_cycle;
24 	struct kvm_vcpu *rvcpu;
25 	struct kvm *kvm = vcpu->kvm;
26 	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
27 
28 	switch (cp->a7) {
29 	case SBI_EXT_0_1_CONSOLE_GETCHAR:
30 	case SBI_EXT_0_1_CONSOLE_PUTCHAR:
31 		/*
32 		 * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be
33 		 * handled in kernel so we forward these to user-space
34 		 */
35 		kvm_riscv_vcpu_sbi_forward(vcpu, run);
36 		*exit = true;
37 		break;
38 	case SBI_EXT_0_1_SET_TIMER:
39 #if __riscv_xlen == 32
40 		next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0;
41 #else
42 		next_cycle = (u64)cp->a0;
43 #endif
44 		ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle);
45 		break;
46 	case SBI_EXT_0_1_CLEAR_IPI:
47 		ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT);
48 		break;
49 	case SBI_EXT_0_1_SEND_IPI:
50 		if (cp->a0)
51 			hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
52 							   utrap);
53 		else
54 			hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
55 		if (utrap->scause)
56 			break;
57 
58 		for_each_set_bit(i, &hmask, BITS_PER_LONG) {
59 			rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
60 			ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT);
61 			if (ret < 0)
62 				break;
63 		}
64 		break;
65 	case SBI_EXT_0_1_SHUTDOWN:
66 		kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
67 						KVM_SYSTEM_EVENT_SHUTDOWN, 0);
68 		*exit = true;
69 		break;
70 	case SBI_EXT_0_1_REMOTE_FENCE_I:
71 	case SBI_EXT_0_1_REMOTE_SFENCE_VMA:
72 	case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID:
73 		if (cp->a0)
74 			hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
75 							   utrap);
76 		else
77 			hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
78 		if (utrap->scause)
79 			break;
80 
81 		if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I)
82 			kvm_riscv_fence_i(vcpu->kvm, 0, hmask);
83 		else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) {
84 			if (cp->a1 == 0 && cp->a2 == 0)
85 				kvm_riscv_hfence_vvma_all(vcpu->kvm,
86 							  0, hmask);
87 			else
88 				kvm_riscv_hfence_vvma_gva(vcpu->kvm,
89 							  0, hmask,
90 							  cp->a1, cp->a2,
91 							  PAGE_SHIFT);
92 		} else {
93 			if (cp->a1 == 0 && cp->a2 == 0)
94 				kvm_riscv_hfence_vvma_asid_all(vcpu->kvm,
95 							       0, hmask,
96 							       cp->a3);
97 			else
98 				kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm,
99 							       0, hmask,
100 							       cp->a1, cp->a2,
101 							       PAGE_SHIFT,
102 							       cp->a3);
103 		}
104 		break;
105 	default:
106 		ret = -EINVAL;
107 		break;
108 	}
109 
110 	return ret;
111 }
112 
113 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
114 	.extid_start = SBI_EXT_0_1_SET_TIMER,
115 	.extid_end = SBI_EXT_0_1_SHUTDOWN,
116 	.handler = kvm_sbi_ext_v01_handler,
117 };
118