xref: /freebsd/sys/dev/hyperv/vmbus/aarch64/hyperv_aarch64.c (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
1 /*- SPDX-License-Identifier: BSD-2-Clause
2  * Copyright (c) 2009-2012,2016-2017, 2022 Microsoft Corp.
3  * Copyright (c) 2012 NetApp Inc.
4  * Copyright (c) 2012 Citrix Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /**
30  * Implements low-level interactions with Hyper-V/Azure
31  */
32 
33 #include <sys/cdefs.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/timetc.h>
39 
40 #include <vm/vm.h>
41 #include <vm/pmap.h>
42 #include <vm/vm_extern.h>
43 #include <vm/vm_kern.h>
44 
45 #include <dev/hyperv/include/hyperv.h>
46 #include <dev/hyperv/include/hyperv_busdma.h>
47 #include <dev/hyperv/vmbus/aarch64/hyperv_machdep.h>
48 #include <dev/hyperv/vmbus/aarch64/hyperv_reg.h>
49 #include <dev/hyperv/vmbus/hyperv_var.h>
50 #include <dev/hyperv/vmbus/hyperv_common_reg.h>
51 #include <contrib/dev/acpica/include/acpi.h>
52 
53 void hyperv_init_tc(void);
54 int hypercall_page_setup(vm_paddr_t);
55 void hypercall_disable(void);
56 bool hyperv_identify_features(void);
57 
58 static bool is_hyperv(void);
59 
60 u_int hyperv_ver_major;
61 u_int hyperv_features;
62 u_int hyperv_recommends;
63 
64 hyperv_tc64_t hyperv_tc64;
65 
66 void
67 hyperv_init_tc(void)
68 {
69 	hyperv_tc64 = NULL;
70 }
71 
72 int
73 hypercall_page_setup(vm_paddr_t hc)
74 {
75 	return (0);
76 }
77 
78 void
79 hypercall_disable(void)
80 {
81 	return;
82 }
83 
84 /*
85  * This function verifies if the platform is Hyper-V or not.
86  * To do that we are using ACPI FADT and for that, acpi
87  * fadt is mapped first.
88  */
89 static bool
90 is_hyperv(void)
91 {
92 	ACPI_TABLE_FADT *fadt;
93 	vm_paddr_t physaddr;
94 	uint64_t hypervid;
95 	bool ret;
96 
97 	physaddr = acpi_find_table(ACPI_SIG_FADT);
98 	if (physaddr == 0)
99 		return (false);
100 
101 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
102 	if (fadt == NULL) {
103 		printf("hyperv: Unable to map the FADT\n");
104 		return (false);
105 	}
106 
107 	hypervid = fadt->HypervisorId;
108 	acpi_unmap_table(fadt);
109 	ret = strncmp((char *)&hypervid, "MsHyperV", 8) == 0 ? true : false;
110 	return (ret);
111 }
112 
113 bool
114 hyperv_identify_features(void)
115 {
116 	struct hv_get_vp_registers_output result;
117 
118 	if (resource_disabled("acpi", 0))
119 		return (false);
120 	if (!is_hyperv())
121 		return (false);
122 
123 	vm_guest = VM_GUEST_HV;
124 	/* use MSRs to get the hyperv specific
125 	 * attributes.
126 	 */
127 	hv_get_vpreg_128(CPUID_LEAF_HV_FEATURES, &result);
128 	hyperv_features = result.as32.a;
129 	hv_get_vpreg_128(CPUID_LEAF_HV_IDENTITY, &result);
130 	hyperv_ver_major = result.as32.b >> 16;
131 	hv_get_vpreg_128(CPUID_LEAF_HV_RECOMMENDS, &result);
132 	hyperv_recommends = result.as32.a;
133 	return (true);
134 }
135