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9#include <linux/types.h>
10#include <linux/time.h>
11#include <linux/clocksource.h>
12#include <linux/init.h>
13#include <linux/export.h>
14#include <linux/hardirq.h>
15#include <linux/efi.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/kexec.h>
19#include <linux/i8253.h>
20#include <linux/random.h>
21#include <asm/processor.h>
22#include <asm/hypervisor.h>
23#include <asm/hyperv-tlfs.h>
24#include <asm/mshyperv.h>
25#include <asm/desc.h>
26#include <asm/idtentry.h>
27#include <asm/irq_regs.h>
28#include <asm/i8259.h>
29#include <asm/apic.h>
30#include <asm/timer.h>
31#include <asm/reboot.h>
32#include <asm/nmi.h>
33#include <clocksource/hyperv_timer.h>
34#include <asm/numa.h>
35
36
37bool hv_root_partition;
38struct ms_hyperv_info ms_hyperv;
39
40#if IS_ENABLED(CONFIG_HYPERV)
41static void (*vmbus_handler)(void);
42static void (*hv_stimer0_handler)(void);
43static void (*hv_kexec_handler)(void);
44static void (*hv_crash_handler)(struct pt_regs *regs);
45
46DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback)
47{
48 struct pt_regs *old_regs = set_irq_regs(regs);
49
50 inc_irq_stat(irq_hv_callback_count);
51 if (vmbus_handler)
52 vmbus_handler();
53
54 if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED)
55 ack_APIC_irq();
56
57 set_irq_regs(old_regs);
58}
59
60void hv_setup_vmbus_handler(void (*handler)(void))
61{
62 vmbus_handler = handler;
63}
64
65void hv_remove_vmbus_handler(void)
66{
67
68 vmbus_handler = NULL;
69}
70
71
72
73
74
75DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_stimer0)
76{
77 struct pt_regs *old_regs = set_irq_regs(regs);
78
79 inc_irq_stat(hyperv_stimer0_count);
80 if (hv_stimer0_handler)
81 hv_stimer0_handler();
82 add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0);
83 ack_APIC_irq();
84
85 set_irq_regs(old_regs);
86}
87
88
89void hv_setup_stimer0_handler(void (*handler)(void))
90{
91 hv_stimer0_handler = handler;
92}
93
94void hv_remove_stimer0_handler(void)
95{
96
97 hv_stimer0_handler = NULL;
98}
99
100void hv_setup_kexec_handler(void (*handler)(void))
101{
102 hv_kexec_handler = handler;
103}
104
105void hv_remove_kexec_handler(void)
106{
107 hv_kexec_handler = NULL;
108}
109
110void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs))
111{
112 hv_crash_handler = handler;
113}
114
115void hv_remove_crash_handler(void)
116{
117 hv_crash_handler = NULL;
118}
119
120#ifdef CONFIG_KEXEC_CORE
121static void hv_machine_shutdown(void)
122{
123 if (kexec_in_progress && hv_kexec_handler)
124 hv_kexec_handler();
125
126
127
128
129
130 if (kexec_in_progress && hyperv_init_cpuhp > 0)
131 cpuhp_remove_state(hyperv_init_cpuhp);
132
133
134 native_machine_shutdown();
135
136
137 if (kexec_in_progress)
138 hyperv_cleanup();
139}
140
141static void hv_machine_crash_shutdown(struct pt_regs *regs)
142{
143 if (hv_crash_handler)
144 hv_crash_handler(regs);
145
146
147 native_machine_crash_shutdown(regs);
148
149
150 hyperv_cleanup();
151}
152#endif
153#endif
154
155static uint32_t __init ms_hyperv_platform(void)
156{
157 u32 eax;
158 u32 hyp_signature[3];
159
160 if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
161 return 0;
162
163 cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
164 &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
165
166 if (eax >= HYPERV_CPUID_MIN &&
167 eax <= HYPERV_CPUID_MAX &&
168 !memcmp("Microsoft Hv", hyp_signature, 12))
169 return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS;
170
171 return 0;
172}
173
174static unsigned char hv_get_nmi_reason(void)
175{
176 return 0;
177}
178
179#ifdef CONFIG_X86_LOCAL_APIC
180
181
182
183
184
185static int hv_nmi_unknown(unsigned int val, struct pt_regs *regs)
186{
187 static atomic_t nmi_cpu = ATOMIC_INIT(-1);
188
189 if (!unknown_nmi_panic)
190 return NMI_DONE;
191
192 if (atomic_cmpxchg(&nmi_cpu, -1, raw_smp_processor_id()) != -1)
193 return NMI_HANDLED;
194
195 return NMI_DONE;
196}
197#endif
198
199static unsigned long hv_get_tsc_khz(void)
200{
201 unsigned long freq;
202
203 rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq);
204
205 return freq / 1000;
206}
207
208#if defined(CONFIG_SMP) && IS_ENABLED(CONFIG_HYPERV)
209static void __init hv_smp_prepare_boot_cpu(void)
210{
211 native_smp_prepare_boot_cpu();
212#if defined(CONFIG_X86_64) && defined(CONFIG_PARAVIRT_SPINLOCKS)
213 hv_init_spinlocks();
214#endif
215}
216
217static void __init hv_smp_prepare_cpus(unsigned int max_cpus)
218{
219#ifdef CONFIG_X86_64
220 int i;
221 int ret;
222#endif
223
224 native_smp_prepare_cpus(max_cpus);
225
226#ifdef CONFIG_X86_64
227 for_each_present_cpu(i) {
228 if (i == 0)
229 continue;
230 ret = hv_call_add_logical_proc(numa_cpu_node(i), i, cpu_physical_id(i));
231 BUG_ON(ret);
232 }
233
234 for_each_present_cpu(i) {
235 if (i == 0)
236 continue;
237 ret = hv_call_create_vp(numa_cpu_node(i), hv_current_partition_id, i, i);
238 BUG_ON(ret);
239 }
240#endif
241}
242#endif
243
244static void __init ms_hyperv_init_platform(void)
245{
246 int hv_max_functions_eax;
247 int hv_host_info_eax;
248 int hv_host_info_ebx;
249 int hv_host_info_ecx;
250 int hv_host_info_edx;
251
252#ifdef CONFIG_PARAVIRT
253 pv_info.name = "Hyper-V";
254#endif
255
256
257
258
259 ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES);
260 ms_hyperv.priv_high = cpuid_ebx(HYPERV_CPUID_FEATURES);
261 ms_hyperv.misc_features = cpuid_edx(HYPERV_CPUID_FEATURES);
262 ms_hyperv.hints = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO);
263
264 hv_max_functions_eax = cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS);
265
266 pr_info("Hyper-V: privilege flags low 0x%x, high 0x%x, hints 0x%x, misc 0x%x\n",
267 ms_hyperv.features, ms_hyperv.priv_high, ms_hyperv.hints,
268 ms_hyperv.misc_features);
269
270 ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
271 ms_hyperv.max_lp_index = cpuid_ebx(HYPERV_CPUID_IMPLEMENT_LIMITS);
272
273 pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
274 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
275
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287 if (cpuid_ebx(HYPERV_CPUID_FEATURES) & HV_CPU_MANAGEMENT) {
288 hv_root_partition = true;
289 pr_info("Hyper-V: running as root partition\n");
290 }
291
292
293
294
295 if (hv_max_functions_eax >= HYPERV_CPUID_VERSION) {
296 hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
297 hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
298 hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
299 hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
300
301 pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d\n",
302 hv_host_info_eax, hv_host_info_ebx >> 16,
303 hv_host_info_ebx & 0xFFFF, hv_host_info_ecx,
304 hv_host_info_edx >> 24, hv_host_info_edx & 0xFFFFFF);
305 }
306
307 if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS &&
308 ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
309 x86_platform.calibrate_tsc = hv_get_tsc_khz;
310 x86_platform.calibrate_cpu = hv_get_tsc_khz;
311 }
312
313 if (ms_hyperv.priv_high & HV_ISOLATION) {
314 ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG);
315 ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG);
316
317 pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n",
318 ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);
319 }
320
321 if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) {
322 ms_hyperv.nested_features =
323 cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
324 pr_info("Hyper-V: Nested features: 0x%x\n",
325 ms_hyperv.nested_features);
326 }
327
328#ifdef CONFIG_X86_LOCAL_APIC
329 if (ms_hyperv.features & HV_ACCESS_FREQUENCY_MSRS &&
330 ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
331
332
333
334 u64 hv_lapic_frequency;
335
336 rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency);
337 hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ);
338 lapic_timer_period = hv_lapic_frequency;
339 pr_info("Hyper-V: LAPIC Timer Frequency: %#x\n",
340 lapic_timer_period);
341 }
342
343 register_nmi_handler(NMI_UNKNOWN, hv_nmi_unknown, NMI_FLAG_FIRST,
344 "hv_nmi_unknown");
345#endif
346
347#ifdef CONFIG_X86_IO_APIC
348 no_timer_check = 1;
349#endif
350
351#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
352 machine_ops.shutdown = hv_machine_shutdown;
353 machine_ops.crash_shutdown = hv_machine_crash_shutdown;
354#endif
355 if (ms_hyperv.features & HV_ACCESS_TSC_INVARIANT) {
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364
365 wrmsrl(HV_X64_MSR_TSC_INVARIANT_CONTROL, 0x1);
366 setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
367 }
368
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372
373 if (efi_enabled(EFI_BOOT))
374 x86_platform.get_nmi_reason = hv_get_nmi_reason;
375
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383
384 i8253_clear_counter_on_shutdown = false;
385
386#if IS_ENABLED(CONFIG_HYPERV)
387
388
389
390 x86_platform.apic_post_init = hyperv_init;
391 hyperv_setup_mmu_ops();
392
393 alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_hyperv_callback);
394
395
396 if (ms_hyperv.features & HV_ACCESS_REENLIGHTENMENT) {
397 alloc_intr_gate(HYPERV_REENLIGHTENMENT_VECTOR,
398 asm_sysvec_hyperv_reenlightenment);
399 }
400
401
402 if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE) {
403 alloc_intr_gate(HYPERV_STIMER0_VECTOR,
404 asm_sysvec_hyperv_stimer0);
405 }
406
407# ifdef CONFIG_SMP
408 smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu;
409 if (hv_root_partition)
410 smp_ops.smp_prepare_cpus = hv_smp_prepare_cpus;
411# endif
412
413
414
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416
417
418
419# ifdef CONFIG_X86_X2APIC
420 if (x2apic_supported())
421 x2apic_phys = 1;
422# endif
423
424
425 hv_init_clocksource();
426#endif
427
428
429
430
431
432 if (!(ms_hyperv.features & HV_ACCESS_TSC_INVARIANT))
433 mark_tsc_unstable("running on Hyper-V");
434}
435
436static bool __init ms_hyperv_x2apic_available(void)
437{
438 return x2apic_supported();
439}
440
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448
449
450
451static bool __init ms_hyperv_msi_ext_dest_id(void)
452{
453 u32 eax;
454
455 eax = cpuid_eax(HYPERV_CPUID_VIRT_STACK_INTERFACE);
456 if (eax != HYPERV_VS_INTERFACE_EAX_SIGNATURE)
457 return false;
458
459 eax = cpuid_eax(HYPERV_CPUID_VIRT_STACK_PROPERTIES);
460 return eax & HYPERV_VS_PROPERTIES_EAX_EXTENDED_IOAPIC_RTE;
461}
462
463const __initconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
464 .name = "Microsoft Hyper-V",
465 .detect = ms_hyperv_platform,
466 .type = X86_HYPER_MS_HYPERV,
467 .init.x2apic_available = ms_hyperv_x2apic_available,
468 .init.msi_ext_dest_id = ms_hyperv_msi_ext_dest_id,
469 .init.init_platform = ms_hyperv_init_platform,
470};
471