xref: /freebsd/sys/riscv/vmm/vmm_sbi.c (revision dd21556857e8d40f66bf5ad54754d9d52669ebf7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2024 Ruslan Bukin <br@bsdpad.com>
5  *
6  * This software was developed by the University of Cambridge Computer
7  * Laboratory (Department of Computer Science and Technology) under Innovate
8  * UK project 105694, "Digital Security by Design (DSbD) Technology Platform
9  * Prototype".
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/jail.h>
36 #include <sys/queue.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/malloc.h>
40 #include <sys/conf.h>
41 #include <sys/sysctl.h>
42 #include <sys/libkern.h>
43 #include <sys/ioccom.h>
44 #include <sys/mman.h>
45 #include <sys/uio.h>
46 #include <sys/proc.h>
47 
48 #include <vm/vm.h>
49 #include <vm/pmap.h>
50 #include <vm/vm_map.h>
51 #include <vm/vm_object.h>
52 
53 #include <machine/machdep.h>
54 #include <machine/vmparam.h>
55 #include <machine/vmm.h>
56 #include <machine/vmm_dev.h>
57 #include <machine/md_var.h>
58 #include <machine/sbi.h>
59 
60 #include "riscv.h"
61 
62 static int
63 vmm_sbi_handle_rfnc(struct vcpu *vcpu, struct hypctx *hypctx)
64 {
65 	uint64_t hart_mask __unused;
66 	uint64_t start __unused;
67 	uint64_t size __unused;
68 	uint64_t asid __unused;
69 	uint64_t func_id;
70 
71 	func_id = hypctx->guest_regs.hyp_a[6];
72 	hart_mask = hypctx->guest_regs.hyp_a[0];
73 	start = hypctx->guest_regs.hyp_a[2];
74 	size = hypctx->guest_regs.hyp_a[3];
75 	asid = hypctx->guest_regs.hyp_a[4];
76 
77 	dprintf("%s: %ld hart_mask %lx start %lx size %lx\n", __func__,
78 	    func_id, hart_mask, start, size);
79 
80 	/* TODO: implement remote sfence. */
81 
82 	switch (func_id) {
83 	case SBI_RFNC_REMOTE_FENCE_I:
84 		break;
85 	case SBI_RFNC_REMOTE_SFENCE_VMA:
86 		break;
87 	case SBI_RFNC_REMOTE_SFENCE_VMA_ASID:
88 		break;
89 	default:
90 		break;
91 	}
92 
93 	hypctx->guest_regs.hyp_a[0] = 0;
94 
95 	return (0);
96 }
97 
98 static int
99 vmm_sbi_handle_time(struct vcpu *vcpu, struct hypctx *hypctx)
100 {
101 	uint64_t func_id;
102 	uint64_t next_val;
103 	int ret;
104 
105 	func_id = hypctx->guest_regs.hyp_a[6];
106 	next_val = hypctx->guest_regs.hyp_a[0];
107 
108 	switch (func_id) {
109 	case SBI_TIME_SET_TIMER:
110 		vtimer_set_timer(hypctx, next_val);
111 		ret = 0;
112 		break;
113 	default:
114 		ret = -1;
115 		break;
116 	}
117 
118 	hypctx->guest_regs.hyp_a[0] = ret;
119 
120 	return (0);
121 }
122 
123 static int
124 vmm_sbi_handle_ipi(struct vcpu *vcpu, struct hypctx *hypctx)
125 {
126 	struct hypctx *target_hypctx;
127 	struct vcpu *target_vcpu __unused;
128 	cpuset_t active_cpus;
129 	struct hyp *hyp;
130 	uint64_t hart_mask;
131 	uint64_t func_id;
132 	int hart_id;
133 	int bit;
134 	int ret;
135 
136 	func_id = hypctx->guest_regs.hyp_a[6];
137 	hart_mask = hypctx->guest_regs.hyp_a[0];
138 
139 	dprintf("%s: hart_mask %lx\n", __func__, hart_mask);
140 
141 	hyp = hypctx->hyp;
142 
143 	active_cpus = vm_active_cpus(hyp->vm);
144 
145 	switch (func_id) {
146 	case SBI_IPI_SEND_IPI:
147 		while ((bit = ffs(hart_mask))) {
148 			hart_id = (bit - 1);
149 			hart_mask &= ~(1u << hart_id);
150 			if (CPU_ISSET(hart_id, &active_cpus)) {
151 				/* TODO. */
152 				target_vcpu = vm_vcpu(hyp->vm, hart_id);
153 				target_hypctx = hypctx->hyp->ctx[hart_id];
154 				riscv_send_ipi(target_hypctx, hart_id);
155 			}
156 		}
157 		ret = 0;
158 		break;
159 	default:
160 		printf("%s: unknown func %ld\n", __func__, func_id);
161 		ret = -1;
162 		break;
163 	}
164 
165 	hypctx->guest_regs.hyp_a[0] = ret;
166 
167 	return (0);
168 }
169 
170 int
171 vmm_sbi_ecall(struct vcpu *vcpu, bool *retu)
172 {
173 	int sbi_extension_id __unused;
174 	struct hypctx *hypctx;
175 
176 	hypctx = riscv_get_active_vcpu();
177 	sbi_extension_id = hypctx->guest_regs.hyp_a[7];
178 
179 	dprintf("%s: args %lx %lx %lx %lx %lx %lx %lx %lx\n", __func__,
180 	    hypctx->guest_regs.hyp_a[0],
181 	    hypctx->guest_regs.hyp_a[1],
182 	    hypctx->guest_regs.hyp_a[2],
183 	    hypctx->guest_regs.hyp_a[3],
184 	    hypctx->guest_regs.hyp_a[4],
185 	    hypctx->guest_regs.hyp_a[5],
186 	    hypctx->guest_regs.hyp_a[6],
187 	    hypctx->guest_regs.hyp_a[7]);
188 
189 	switch (sbi_extension_id) {
190 	case SBI_EXT_ID_RFNC:
191 		vmm_sbi_handle_rfnc(vcpu, hypctx);
192 		break;
193 	case SBI_EXT_ID_TIME:
194 		vmm_sbi_handle_time(vcpu, hypctx);
195 		break;
196 	case SBI_EXT_ID_IPI:
197 		vmm_sbi_handle_ipi(vcpu, hypctx);
198 		break;
199 	default:
200 		*retu = true;
201 		break;
202 	}
203 
204 	return (0);
205 }
206