xref: /linux/arch/riscv/kvm/vcpu_sbi_v01.c (revision 63eb28bb1402891b1ad2be02a530f29a9dd7f1cd)
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 
kvm_sbi_ext_v01_handler(struct kvm_vcpu * vcpu,struct kvm_run * run,struct kvm_vcpu_sbi_return * retdata)16 static 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 	unsigned long vmid;
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 		retdata->uexit = 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, utrap);
52 		else
53 			hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
54 		if (utrap->scause)
55 			break;
56 
57 		for_each_set_bit(i, &hmask, BITS_PER_LONG) {
58 			rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
59 			ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT);
60 			if (ret < 0)
61 				break;
62 		}
63 		break;
64 	case SBI_EXT_0_1_SHUTDOWN:
65 		kvm_riscv_vcpu_sbi_system_reset(vcpu, run,
66 						KVM_SYSTEM_EVENT_SHUTDOWN, 0);
67 		retdata->uexit = true;
68 		break;
69 	case SBI_EXT_0_1_REMOTE_FENCE_I:
70 	case SBI_EXT_0_1_REMOTE_SFENCE_VMA:
71 	case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID:
72 		if (cp->a0)
73 			hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0, utrap);
74 		else
75 			hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
76 		if (utrap->scause)
77 			break;
78 
79 		if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I)
80 			kvm_riscv_fence_i(vcpu->kvm, 0, hmask);
81 		else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) {
82 			vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid);
83 			if (cp->a1 == 0 && cp->a2 == 0)
84 				kvm_riscv_hfence_vvma_all(vcpu->kvm, 0, hmask, vmid);
85 			else
86 				kvm_riscv_hfence_vvma_gva(vcpu->kvm, 0, hmask, cp->a1,
87 							  cp->a2, PAGE_SHIFT, vmid);
88 		} else {
89 			vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid);
90 			if (cp->a1 == 0 && cp->a2 == 0)
91 				kvm_riscv_hfence_vvma_asid_all(vcpu->kvm, 0, hmask,
92 							       cp->a3, vmid);
93 			else
94 				kvm_riscv_hfence_vvma_asid_gva(vcpu->kvm, 0, hmask,
95 							       cp->a1, cp->a2, PAGE_SHIFT,
96 							       cp->a3, vmid);
97 		}
98 		break;
99 	default:
100 		retdata->err_val = SBI_ERR_NOT_SUPPORTED;
101 		break;
102 	}
103 
104 	return ret;
105 }
106 
107 const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
108 	.extid_start = SBI_EXT_0_1_SET_TIMER,
109 	.extid_end = SBI_EXT_0_1_SHUTDOWN,
110 	.handler = kvm_sbi_ext_v01_handler,
111 };
112