Linux Audio

Check our new training course

Loading...
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * HyperV  Detection code.
  4 *
  5 * Copyright (C) 2010, Novell, Inc.
  6 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
  7 */
  8
  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/irq_regs.h>
 27#include <asm/i8259.h>
 28#include <asm/apic.h>
 29#include <asm/timer.h>
 30#include <asm/reboot.h>
 31#include <asm/nmi.h>
 32#include <clocksource/hyperv_timer.h>
 33
 34struct ms_hyperv_info ms_hyperv;
 35EXPORT_SYMBOL_GPL(ms_hyperv);
 36
 37#if IS_ENABLED(CONFIG_HYPERV)
 38static void (*vmbus_handler)(void);
 39static void (*hv_stimer0_handler)(void);
 40static void (*hv_kexec_handler)(void);
 41static void (*hv_crash_handler)(struct pt_regs *regs);
 42
 43__visible void __irq_entry hyperv_vector_handler(struct pt_regs *regs)
 44{
 45	struct pt_regs *old_regs = set_irq_regs(regs);
 46
 47	entering_irq();
 48	inc_irq_stat(irq_hv_callback_count);
 49	if (vmbus_handler)
 50		vmbus_handler();
 51
 52	if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED)
 53		ack_APIC_irq();
 54
 55	exiting_irq();
 56	set_irq_regs(old_regs);
 57}
 58
 59void hv_setup_vmbus_irq(void (*handler)(void))
 60{
 61	vmbus_handler = handler;
 62}
 63
 64void hv_remove_vmbus_irq(void)
 65{
 66	/* We have no way to deallocate the interrupt gate */
 67	vmbus_handler = NULL;
 68}
 69EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq);
 70EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
 71
 72/*
 73 * Routines to do per-architecture handling of stimer0
 74 * interrupts when in Direct Mode
 75 */
 76
 77__visible void __irq_entry hv_stimer0_vector_handler(struct pt_regs *regs)
 78{
 79	struct pt_regs *old_regs = set_irq_regs(regs);
 80
 81	entering_irq();
 82	inc_irq_stat(hyperv_stimer0_count);
 83	if (hv_stimer0_handler)
 84		hv_stimer0_handler();
 85	add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0);
 86	ack_APIC_irq();
 87
 88	exiting_irq();
 89	set_irq_regs(old_regs);
 90}
 91
 92int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void))
 93{
 94	*vector = HYPERV_STIMER0_VECTOR;
 95	*irq = -1;   /* Unused on x86/x64 */
 96	hv_stimer0_handler = handler;
 97	return 0;
 98}
 99EXPORT_SYMBOL_GPL(hv_setup_stimer0_irq);
100
101void hv_remove_stimer0_irq(int irq)
102{
103	/* We have no way to deallocate the interrupt gate */
104	hv_stimer0_handler = NULL;
105}
106EXPORT_SYMBOL_GPL(hv_remove_stimer0_irq);
107
108void hv_setup_kexec_handler(void (*handler)(void))
109{
110	hv_kexec_handler = handler;
111}
112EXPORT_SYMBOL_GPL(hv_setup_kexec_handler);
113
114void hv_remove_kexec_handler(void)
115{
116	hv_kexec_handler = NULL;
117}
118EXPORT_SYMBOL_GPL(hv_remove_kexec_handler);
119
120void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs))
121{
122	hv_crash_handler = handler;
123}
124EXPORT_SYMBOL_GPL(hv_setup_crash_handler);
125
126void hv_remove_crash_handler(void)
127{
128	hv_crash_handler = NULL;
129}
130EXPORT_SYMBOL_GPL(hv_remove_crash_handler);
131
132#ifdef CONFIG_KEXEC_CORE
133static void hv_machine_shutdown(void)
134{
135	if (kexec_in_progress && hv_kexec_handler)
136		hv_kexec_handler();
137	native_machine_shutdown();
138}
139
140static void hv_machine_crash_shutdown(struct pt_regs *regs)
141{
142	if (hv_crash_handler)
143		hv_crash_handler(regs);
144	native_machine_crash_shutdown(regs);
145}
146#endif /* CONFIG_KEXEC_CORE */
147#endif /* CONFIG_HYPERV */
148
149static uint32_t  __init ms_hyperv_platform(void)
150{
151	u32 eax;
152	u32 hyp_signature[3];
153
154	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
155		return 0;
156
157	cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
158	      &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
159
160	if (eax >= HYPERV_CPUID_MIN &&
161	    eax <= HYPERV_CPUID_MAX &&
162	    !memcmp("Microsoft Hv", hyp_signature, 12))
163		return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS;
164
165	return 0;
166}
167
168static unsigned char hv_get_nmi_reason(void)
169{
170	return 0;
171}
172
173#ifdef CONFIG_X86_LOCAL_APIC
174/*
175 * Prior to WS2016 Debug-VM sends NMIs to all CPUs which makes
176 * it dificult to process CHANNELMSG_UNLOAD in case of crash. Handle
177 * unknown NMI on the first CPU which gets it.
178 */
179static int hv_nmi_unknown(unsigned int val, struct pt_regs *regs)
180{
181	static atomic_t nmi_cpu = ATOMIC_INIT(-1);
182
183	if (!unknown_nmi_panic)
184		return NMI_DONE;
185
186	if (atomic_cmpxchg(&nmi_cpu, -1, raw_smp_processor_id()) != -1)
187		return NMI_HANDLED;
188
189	return NMI_DONE;
190}
191#endif
192
193static unsigned long hv_get_tsc_khz(void)
194{
195	unsigned long freq;
196
197	rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq);
198
199	return freq / 1000;
200}
201
202#if defined(CONFIG_SMP) && IS_ENABLED(CONFIG_HYPERV)
203static void __init hv_smp_prepare_boot_cpu(void)
204{
205	native_smp_prepare_boot_cpu();
206#if defined(CONFIG_X86_64) && defined(CONFIG_PARAVIRT_SPINLOCKS)
207	hv_init_spinlocks();
208#endif
209}
210#endif
211
212static void __init ms_hyperv_init_platform(void)
213{
214	int hv_host_info_eax;
215	int hv_host_info_ebx;
216	int hv_host_info_ecx;
217	int hv_host_info_edx;
218
219#ifdef CONFIG_PARAVIRT
220	pv_info.name = "Hyper-V";
221#endif
222
223	/*
224	 * Extract the features and hints
225	 */
226	ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES);
227	ms_hyperv.misc_features = cpuid_edx(HYPERV_CPUID_FEATURES);
228	ms_hyperv.hints    = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO);
229
230	pr_info("Hyper-V: features 0x%x, hints 0x%x\n",
231		ms_hyperv.features, ms_hyperv.hints);
232
233	ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
234	ms_hyperv.max_lp_index = cpuid_ebx(HYPERV_CPUID_IMPLEMENT_LIMITS);
235
236	pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
237		 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
238
239	/*
240	 * Extract host information.
241	 */
242	if (cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS) >=
243	    HYPERV_CPUID_VERSION) {
244		hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
245		hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
246		hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
247		hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
248
249		pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d\n",
250			hv_host_info_eax, hv_host_info_ebx >> 16,
251			hv_host_info_ebx & 0xFFFF, hv_host_info_ecx,
252			hv_host_info_edx >> 24, hv_host_info_edx & 0xFFFFFF);
253	}
254
255	if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
256	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
257		x86_platform.calibrate_tsc = hv_get_tsc_khz;
258		x86_platform.calibrate_cpu = hv_get_tsc_khz;
259	}
260
261	if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
262		ms_hyperv.nested_features =
263			cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
264	}
265
 
 
 
 
 
 
 
 
 
 
266#ifdef CONFIG_X86_LOCAL_APIC
267	if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
268	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
269		/*
270		 * Get the APIC frequency.
271		 */
272		u64	hv_lapic_frequency;
273
274		rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency);
275		hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ);
276		lapic_timer_period = hv_lapic_frequency;
277		pr_info("Hyper-V: LAPIC Timer Frequency: %#x\n",
278			lapic_timer_period);
279	}
280
281	register_nmi_handler(NMI_UNKNOWN, hv_nmi_unknown, NMI_FLAG_FIRST,
282			     "hv_nmi_unknown");
283#endif
284
285#ifdef CONFIG_X86_IO_APIC
286	no_timer_check = 1;
287#endif
288
289#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
290	machine_ops.shutdown = hv_machine_shutdown;
291	machine_ops.crash_shutdown = hv_machine_crash_shutdown;
292#endif
293	mark_tsc_unstable("running on Hyper-V");
 
 
 
 
 
294
295	/*
296	 * Generation 2 instances don't support reading the NMI status from
297	 * 0x61 port.
298	 */
299	if (efi_enabled(EFI_BOOT))
300		x86_platform.get_nmi_reason = hv_get_nmi_reason;
301
302	/*
303	 * Hyper-V VMs have a PIT emulation quirk such that zeroing the
304	 * counter register during PIT shutdown restarts the PIT. So it
305	 * continues to interrupt @18.2 HZ. Setting i8253_clear_counter
306	 * to false tells pit_shutdown() not to zero the counter so that
307	 * the PIT really is shutdown. Generation 2 VMs don't have a PIT,
308	 * and setting this value has no effect.
309	 */
310	i8253_clear_counter_on_shutdown = false;
311
312#if IS_ENABLED(CONFIG_HYPERV)
313	/*
314	 * Setup the hook to get control post apic initialization.
315	 */
316	x86_platform.apic_post_init = hyperv_init;
317	hyperv_setup_mmu_ops();
318	/* Setup the IDT for hypervisor callback */
319	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector);
320
321	/* Setup the IDT for reenlightenment notifications */
322	if (ms_hyperv.features & HV_X64_ACCESS_REENLIGHTENMENT)
323		alloc_intr_gate(HYPERV_REENLIGHTENMENT_VECTOR,
324				hyperv_reenlightenment_vector);
 
325
326	/* Setup the IDT for stimer0 */
327	if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE)
328		alloc_intr_gate(HYPERV_STIMER0_VECTOR,
329				hv_stimer0_callback_vector);
 
330
331# ifdef CONFIG_SMP
332	smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu;
333# endif
334
335	/*
336	 * Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
337	 * set x2apic destination mode to physcial mode when x2apic is available
338	 * and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs
339	 * have 8-bit APIC id.
340	 */
341# ifdef CONFIG_X86_X2APIC
342	if (x2apic_supported())
343		x2apic_phys = 1;
344# endif
345
346	/* Register Hyper-V specific clocksource */
347	hv_init_clocksource();
348#endif
349}
350
351void hv_setup_sched_clock(void *sched_clock)
352{
353#ifdef CONFIG_PARAVIRT
354	pv_ops.time.sched_clock = sched_clock;
355#endif
356}
357
358const __initconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
359	.name			= "Microsoft Hyper-V",
360	.detect			= ms_hyperv_platform,
361	.type			= X86_HYPER_MS_HYPERV,
362	.init.init_platform	= ms_hyperv_init_platform,
363};
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * HyperV  Detection code.
  4 *
  5 * Copyright (C) 2010, Novell, Inc.
  6 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
  7 */
  8
  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
 35struct ms_hyperv_info ms_hyperv;
 36EXPORT_SYMBOL_GPL(ms_hyperv);
 37
 38#if IS_ENABLED(CONFIG_HYPERV)
 39static void (*vmbus_handler)(void);
 40static void (*hv_stimer0_handler)(void);
 41static void (*hv_kexec_handler)(void);
 42static void (*hv_crash_handler)(struct pt_regs *regs);
 43
 44DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback)
 45{
 46	struct pt_regs *old_regs = set_irq_regs(regs);
 47
 
 48	inc_irq_stat(irq_hv_callback_count);
 49	if (vmbus_handler)
 50		vmbus_handler();
 51
 52	if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED)
 53		ack_APIC_irq();
 54
 
 55	set_irq_regs(old_regs);
 56}
 57
 58void hv_setup_vmbus_irq(void (*handler)(void))
 59{
 60	vmbus_handler = handler;
 61}
 62
 63void hv_remove_vmbus_irq(void)
 64{
 65	/* We have no way to deallocate the interrupt gate */
 66	vmbus_handler = NULL;
 67}
 68EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq);
 69EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq);
 70
 71/*
 72 * Routines to do per-architecture handling of stimer0
 73 * interrupts when in Direct Mode
 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
 88int hv_setup_stimer0_irq(int *irq, int *vector, void (*handler)(void))
 89{
 90	*vector = HYPERV_STIMER0_VECTOR;
 91	*irq = -1;   /* Unused on x86/x64 */
 92	hv_stimer0_handler = handler;
 93	return 0;
 94}
 95EXPORT_SYMBOL_GPL(hv_setup_stimer0_irq);
 96
 97void hv_remove_stimer0_irq(int irq)
 98{
 99	/* We have no way to deallocate the interrupt gate */
100	hv_stimer0_handler = NULL;
101}
102EXPORT_SYMBOL_GPL(hv_remove_stimer0_irq);
103
104void hv_setup_kexec_handler(void (*handler)(void))
105{
106	hv_kexec_handler = handler;
107}
108EXPORT_SYMBOL_GPL(hv_setup_kexec_handler);
109
110void hv_remove_kexec_handler(void)
111{
112	hv_kexec_handler = NULL;
113}
114EXPORT_SYMBOL_GPL(hv_remove_kexec_handler);
115
116void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs))
117{
118	hv_crash_handler = handler;
119}
120EXPORT_SYMBOL_GPL(hv_setup_crash_handler);
121
122void hv_remove_crash_handler(void)
123{
124	hv_crash_handler = NULL;
125}
126EXPORT_SYMBOL_GPL(hv_remove_crash_handler);
127
128#ifdef CONFIG_KEXEC_CORE
129static void hv_machine_shutdown(void)
130{
131	if (kexec_in_progress && hv_kexec_handler)
132		hv_kexec_handler();
133	native_machine_shutdown();
134}
135
136static void hv_machine_crash_shutdown(struct pt_regs *regs)
137{
138	if (hv_crash_handler)
139		hv_crash_handler(regs);
140	native_machine_crash_shutdown(regs);
141}
142#endif /* CONFIG_KEXEC_CORE */
143#endif /* CONFIG_HYPERV */
144
145static uint32_t  __init ms_hyperv_platform(void)
146{
147	u32 eax;
148	u32 hyp_signature[3];
149
150	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
151		return 0;
152
153	cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
154	      &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
155
156	if (eax >= HYPERV_CPUID_MIN &&
157	    eax <= HYPERV_CPUID_MAX &&
158	    !memcmp("Microsoft Hv", hyp_signature, 12))
159		return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS;
160
161	return 0;
162}
163
164static unsigned char hv_get_nmi_reason(void)
165{
166	return 0;
167}
168
169#ifdef CONFIG_X86_LOCAL_APIC
170/*
171 * Prior to WS2016 Debug-VM sends NMIs to all CPUs which makes
172 * it dificult to process CHANNELMSG_UNLOAD in case of crash. Handle
173 * unknown NMI on the first CPU which gets it.
174 */
175static int hv_nmi_unknown(unsigned int val, struct pt_regs *regs)
176{
177	static atomic_t nmi_cpu = ATOMIC_INIT(-1);
178
179	if (!unknown_nmi_panic)
180		return NMI_DONE;
181
182	if (atomic_cmpxchg(&nmi_cpu, -1, raw_smp_processor_id()) != -1)
183		return NMI_HANDLED;
184
185	return NMI_DONE;
186}
187#endif
188
189static unsigned long hv_get_tsc_khz(void)
190{
191	unsigned long freq;
192
193	rdmsrl(HV_X64_MSR_TSC_FREQUENCY, freq);
194
195	return freq / 1000;
196}
197
198#if defined(CONFIG_SMP) && IS_ENABLED(CONFIG_HYPERV)
199static void __init hv_smp_prepare_boot_cpu(void)
200{
201	native_smp_prepare_boot_cpu();
202#if defined(CONFIG_X86_64) && defined(CONFIG_PARAVIRT_SPINLOCKS)
203	hv_init_spinlocks();
204#endif
205}
206#endif
207
208static void __init ms_hyperv_init_platform(void)
209{
210	int hv_host_info_eax;
211	int hv_host_info_ebx;
212	int hv_host_info_ecx;
213	int hv_host_info_edx;
214
215#ifdef CONFIG_PARAVIRT
216	pv_info.name = "Hyper-V";
217#endif
218
219	/*
220	 * Extract the features and hints
221	 */
222	ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES);
223	ms_hyperv.misc_features = cpuid_edx(HYPERV_CPUID_FEATURES);
224	ms_hyperv.hints    = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO);
225
226	pr_info("Hyper-V: features 0x%x, hints 0x%x, misc 0x%x\n",
227		ms_hyperv.features, ms_hyperv.hints, ms_hyperv.misc_features);
228
229	ms_hyperv.max_vp_index = cpuid_eax(HYPERV_CPUID_IMPLEMENT_LIMITS);
230	ms_hyperv.max_lp_index = cpuid_ebx(HYPERV_CPUID_IMPLEMENT_LIMITS);
231
232	pr_debug("Hyper-V: max %u virtual processors, %u logical processors\n",
233		 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
234
235	/*
236	 * Extract host information.
237	 */
238	if (cpuid_eax(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS) >=
239	    HYPERV_CPUID_VERSION) {
240		hv_host_info_eax = cpuid_eax(HYPERV_CPUID_VERSION);
241		hv_host_info_ebx = cpuid_ebx(HYPERV_CPUID_VERSION);
242		hv_host_info_ecx = cpuid_ecx(HYPERV_CPUID_VERSION);
243		hv_host_info_edx = cpuid_edx(HYPERV_CPUID_VERSION);
244
245		pr_info("Hyper-V Host Build:%d-%d.%d-%d-%d.%d\n",
246			hv_host_info_eax, hv_host_info_ebx >> 16,
247			hv_host_info_ebx & 0xFFFF, hv_host_info_ecx,
248			hv_host_info_edx >> 24, hv_host_info_edx & 0xFFFFFF);
249	}
250
251	if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
252	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
253		x86_platform.calibrate_tsc = hv_get_tsc_khz;
254		x86_platform.calibrate_cpu = hv_get_tsc_khz;
255	}
256
257	if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED) {
258		ms_hyperv.nested_features =
259			cpuid_eax(HYPERV_CPUID_NESTED_FEATURES);
260	}
261
262	/*
263	 * Hyper-V expects to get crash register data or kmsg when
264	 * crash enlightment is available and system crashes. Set
265	 * crash_kexec_post_notifiers to be true to make sure that
266	 * calling crash enlightment interface before running kdump
267	 * kernel.
268	 */
269	if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE)
270		crash_kexec_post_notifiers = true;
271
272#ifdef CONFIG_X86_LOCAL_APIC
273	if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS &&
274	    ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) {
275		/*
276		 * Get the APIC frequency.
277		 */
278		u64	hv_lapic_frequency;
279
280		rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency);
281		hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ);
282		lapic_timer_period = hv_lapic_frequency;
283		pr_info("Hyper-V: LAPIC Timer Frequency: %#x\n",
284			lapic_timer_period);
285	}
286
287	register_nmi_handler(NMI_UNKNOWN, hv_nmi_unknown, NMI_FLAG_FIRST,
288			     "hv_nmi_unknown");
289#endif
290
291#ifdef CONFIG_X86_IO_APIC
292	no_timer_check = 1;
293#endif
294
295#if IS_ENABLED(CONFIG_HYPERV) && defined(CONFIG_KEXEC_CORE)
296	machine_ops.shutdown = hv_machine_shutdown;
297	machine_ops.crash_shutdown = hv_machine_crash_shutdown;
298#endif
299	if (ms_hyperv.features & HV_X64_ACCESS_TSC_INVARIANT) {
300		wrmsrl(HV_X64_MSR_TSC_INVARIANT_CONTROL, 0x1);
301		setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
302	} else {
303		mark_tsc_unstable("running on Hyper-V");
304	}
305
306	/*
307	 * Generation 2 instances don't support reading the NMI status from
308	 * 0x61 port.
309	 */
310	if (efi_enabled(EFI_BOOT))
311		x86_platform.get_nmi_reason = hv_get_nmi_reason;
312
313	/*
314	 * Hyper-V VMs have a PIT emulation quirk such that zeroing the
315	 * counter register during PIT shutdown restarts the PIT. So it
316	 * continues to interrupt @18.2 HZ. Setting i8253_clear_counter
317	 * to false tells pit_shutdown() not to zero the counter so that
318	 * the PIT really is shutdown. Generation 2 VMs don't have a PIT,
319	 * and setting this value has no effect.
320	 */
321	i8253_clear_counter_on_shutdown = false;
322
323#if IS_ENABLED(CONFIG_HYPERV)
324	/*
325	 * Setup the hook to get control post apic initialization.
326	 */
327	x86_platform.apic_post_init = hyperv_init;
328	hyperv_setup_mmu_ops();
329	/* Setup the IDT for hypervisor callback */
330	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_hyperv_callback);
331
332	/* Setup the IDT for reenlightenment notifications */
333	if (ms_hyperv.features & HV_X64_ACCESS_REENLIGHTENMENT) {
334		alloc_intr_gate(HYPERV_REENLIGHTENMENT_VECTOR,
335				asm_sysvec_hyperv_reenlightenment);
336	}
337
338	/* Setup the IDT for stimer0 */
339	if (ms_hyperv.misc_features & HV_STIMER_DIRECT_MODE_AVAILABLE) {
340		alloc_intr_gate(HYPERV_STIMER0_VECTOR,
341				asm_sysvec_hyperv_stimer0);
342	}
343
344# ifdef CONFIG_SMP
345	smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu;
346# endif
347
348	/*
349	 * Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
350	 * set x2apic destination mode to physcial mode when x2apic is available
351	 * and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs
352	 * have 8-bit APIC id.
353	 */
354# ifdef CONFIG_X86_X2APIC
355	if (x2apic_supported())
356		x2apic_phys = 1;
357# endif
358
359	/* Register Hyper-V specific clocksource */
360	hv_init_clocksource();
 
 
 
 
 
 
 
361#endif
362}
363
364const __initconst struct hypervisor_x86 x86_hyper_ms_hyperv = {
365	.name			= "Microsoft Hyper-V",
366	.detect			= ms_hyperv_platform,
367	.type			= X86_HYPER_MS_HYPERV,
368	.init.init_platform	= ms_hyperv_init_platform,
369};