xref: /freebsd/sys/dev/hyperv/vmbus/x86/hyperv_x86.c (revision 6fe0a6c80a1aff14236924eb33e4013aa8c14f91)
1 /*- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/timetc.h>
40 
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 #include <vm/vm_extern.h>
44 #include <vm/vm_kern.h>
45 
46 #include <dev/hyperv/include/hyperv.h>
47 #include <dev/hyperv/include/hyperv_busdma.h>
48 #include <dev/hyperv/vmbus/hyperv_var.h>
49 #include <dev/hyperv/vmbus/x86/hyperv_machdep.h>
50 #include <dev/hyperv/vmbus/x86/hyperv_reg.h>
51 
52 #define HYPERV_FREEBSD_BUILD 0ULL
53 #define HYPERV_FREEBSD_VERSION ((uint64_t)__FreeBSD_version)
54 #define HYPERV_FREEBSD_OSID 0ULL
55 
56 void hyperv_init_tc(void);
57 int hypercall_page_setup(vm_paddr_t);
58 void hypercall_disable(void);
59 bool hyperv_identify_features(void);
60 
61 u_int hyperv_ver_major;
62 u_int hyperv_features;
63 u_int hyperv_recommends;
64 
65 hyperv_tc64_t hyperv_tc64;
66 
67 static u_int hyperv_pm_features;
68 static u_int hyperv_features3;
69 static u_int hyperv_get_timecount(struct timecounter *);
70 
71 static struct timecounter hyperv_timecounter = {
72 	.tc_get_timecount = hyperv_get_timecount,
73 	.tc_poll_pps = NULL,
74 	.tc_counter_mask = 0xffffffff,
75 	.tc_frequency = HYPERV_TIMER_FREQ,
76 	.tc_name = "Hyper-V",
77 	.tc_quality = 2000,
78 	.tc_flags = 0,
79 	.tc_priv = NULL
80 };
81 
82 static u_int
83 hyperv_get_timecount(struct timecounter *tc __unused)
84 {
85 	return rdmsr(MSR_HV_TIME_REF_COUNT);
86 }
87 
88 static uint64_t
89 hyperv_tc64_rdmsr(void)
90 {
91 
92 	return (rdmsr(MSR_HV_TIME_REF_COUNT));
93 }
94 
95 void
96 hyperv_init_tc(void)
97 {
98 	if (hyperv_features & CPUID_HV_MSR_TIME_REFCNT) {
99 		/*
100 		 * Register Hyper-V timecounter.  This should be done as early
101 		 * as possible to let DELAY() work, since the 8254 PIT is not
102 		 * reliably emulated or even available.
103 		 */
104 		tc_init(&hyperv_timecounter);
105 
106 		/*
107 		 * Install 64 bits timecounter method for other modules
108 		 * to use.
109 		 */
110 		hyperv_tc64 = hyperv_tc64_rdmsr;
111 	}
112 }
113 
114 int
115 hypercall_page_setup(vm_paddr_t paddr)
116 {
117 	uint64_t hc, hc_orig;
118 	hc_orig = rdmsr(MSR_HV_HYPERCALL);
119 
120 	/*
121 	 * Setup the Hypercall page.
122 	 *
123 	 * NOTE: 'reserved' bits MUST be preserved.
124 	 */
125 	hc = ((paddr >> PAGE_SHIFT) << MSR_HV_HYPERCALL_PGSHIFT) |
126 	    (hc_orig & MSR_HV_HYPERCALL_RSVD_MASK) | MSR_HV_HYPERCALL_ENABLE;
127 	wrmsr(MSR_HV_HYPERCALL, hc);
128 
129 	/*
130 	 * Confirm that Hypercall page did get setup.
131 	 */
132 	hc = rdmsr(MSR_HV_HYPERCALL);
133 	if ((hc & MSR_HV_HYPERCALL_ENABLE) == 0) {
134 		printf("hyperv: Hypercall setup failed\n");
135 		/* Can't perform any Hyper-V specific actions */
136 		vm_guest = VM_GUEST_VM;
137 		return (-1);
138 	}
139 	return (0);
140 }
141 
142 void
143 hypercall_disable(void)
144 {
145 	uint64_t hc;
146 	/* Disable Hypercall */
147 	hc = rdmsr(MSR_HV_HYPERCALL);
148 	wrmsr(MSR_HV_HYPERCALL, (hc & MSR_HV_HYPERCALL_RSVD_MASK));
149 }
150 
151 bool
152 hyperv_identify_features(void)
153 {
154 	u_int regs[4];
155 	unsigned int maxleaf;
156 
157 	if (vm_guest != VM_GUEST_HV)
158 		return (false);
159 
160 	do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs);
161 	maxleaf = regs[0];
162 	if (maxleaf < CPUID_LEAF_HV_LIMITS)
163 		return (false);
164 
165 	do_cpuid(CPUID_LEAF_HV_INTERFACE, regs);
166 	if (regs[0] != CPUID_HV_IFACE_HYPERV)
167 		return (false);
168 
169 	do_cpuid(CPUID_LEAF_HV_FEATURES, regs);
170 	if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) {
171 		/*
172 		 * Hyper-V w/o Hypercall is impossible; someone
173 		 * is faking Hyper-V.
174 		 */
175 		return (false);
176 	}
177 	hyperv_features = regs[0];
178 	hyperv_pm_features = regs[2];
179 	hyperv_features3 = regs[3];
180 	do_cpuid(CPUID_LEAF_HV_IDENTITY, regs);
181 	hyperv_ver_major = regs[1] >> 16;
182 	printf("Hyper-V Version: %d.%d.%d [SP%d]\n", hyperv_ver_major,
183 	    regs[1] & 0xffff, regs[0], regs[2]);
184 
185 	printf("  Features=0x%b\n", hyperv_features,
186 	    "\020"
187 	    "\001VPRUNTIME" /* MSR_HV_VP_RUNTIME */
188 	    "\002TMREFCNT"  /* MSR_HV_TIME_REF_COUNT */
189 	    "\003SYNIC"	    /* MSRs for SynIC */
190 	    "\004SYNTM"	    /* MSRs for SynTimer */
191 	    "\005APIC"	    /* MSR_HV_{EOI,ICR,TPR} */
192 	    "\006HYPERCALL" /* MSR_HV_{GUEST_OS_ID,HYPERCALL} */
193 	    "\007VPINDEX"   /* MSR_HV_VP_INDEX */
194 	    "\010RESET"	    /* MSR_HV_RESET */
195 	    "\011STATS"	    /* MSR_HV_STATS_ */
196 	    "\012REFTSC"    /* MSR_HV_REFERENCE_TSC */
197 	    "\013IDLE"	    /* MSR_HV_GUEST_IDLE */
198 	    "\014TMFREQ"    /* MSR_HV_{TSC,APIC}_FREQUENCY */
199 	    "\015DEBUG");   /* MSR_HV_SYNTH_DEBUG_ */
200 	printf("  PM Features=0x%b [C%u]\n",
201 	    (hyperv_pm_features & ~CPUPM_HV_CSTATE_MASK),
202 	    "\020"
203 	    "\005C3HPET", /* HPET is required for C3 state */
204 	    CPUPM_HV_CSTATE(hyperv_pm_features));
205 	printf("  Features3=0x%b\n", hyperv_features3,
206 	    "\020"
207 	    "\001MWAIT"	   /* MWAIT */
208 	    "\002DEBUG"	   /* guest debug support */
209 	    "\003PERFMON"  /* performance monitor */
210 	    "\004PCPUDPE"  /* physical CPU dynamic partition event */
211 	    "\005XMMHC"	   /* hypercall input through XMM regs */
212 	    "\006IDLE"	   /* guest idle support */
213 	    "\007SLEEP"	   /* hypervisor sleep support */
214 	    "\010NUMA"	   /* NUMA distance query support */
215 	    "\011TMFREQ"   /* timer frequency query (TSC, LAPIC) */
216 	    "\012SYNCMC"   /* inject synthetic machine checks */
217 	    "\013CRASH"	   /* MSRs for guest crash */
218 	    "\014DEBUGMSR" /* MSRs for guest debug */
219 	    "\015NPIEP"	   /* NPIEP */
220 	    "\016HVDIS");  /* disabling hypervisor */
221 
222 	do_cpuid(CPUID_LEAF_HV_RECOMMENDS, regs);
223 	hyperv_recommends = regs[0];
224 	if (bootverbose)
225 		printf("  Recommends: %08x %08x\n", regs[0], regs[1]);
226 
227 	do_cpuid(CPUID_LEAF_HV_LIMITS, regs);
228 	if (bootverbose) {
229 		printf("  Limits: Vcpu:%d Lcpu:%d Int:%d\n", regs[0], regs[1],
230 		    regs[2]);
231 	}
232 
233 	if (maxleaf >= CPUID_LEAF_HV_HWFEATURES) {
234 		do_cpuid(CPUID_LEAF_HV_HWFEATURES, regs);
235 		if (bootverbose) {
236 			printf("  HW Features: %08x, AMD: %08x\n", regs[0],
237 			    regs[3]);
238 		}
239 	}
240 	return (true);
241 }
242