Commit | Line | Data |
---|---|---|
a2a47c6c KS |
1 | /* |
2 | * HyperV Detection code. | |
3 | * | |
4 | * Copyright (C) 2010, Novell, Inc. | |
5 | * Author : K. Y. Srinivasan <ksrinivasan@novell.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9fa02317 | 9 | * the Free Software Foundation; version 2 of the License. |
a2a47c6c KS |
10 | * |
11 | */ | |
12 | ||
13 | #include <linux/types.h> | |
6f4151c8 S |
14 | #include <linux/time.h> |
15 | #include <linux/clocksource.h> | |
3998d095 | 16 | #include <linux/module.h> |
bc2b0331 | 17 | #include <linux/hardirq.h> |
9e7827b5 | 18 | #include <linux/efi.h> |
bc2b0331 | 19 | #include <linux/interrupt.h> |
a2a47c6c | 20 | #include <asm/processor.h> |
e08cae41 | 21 | #include <asm/hypervisor.h> |
a2a47c6c KS |
22 | #include <asm/hyperv.h> |
23 | #include <asm/mshyperv.h> | |
bc2b0331 S |
24 | #include <asm/desc.h> |
25 | #include <asm/idle.h> | |
26 | #include <asm/irq_regs.h> | |
9e7827b5 | 27 | #include <asm/i8259.h> |
a2a47c6c | 28 | |
e08cae41 | 29 | struct ms_hyperv_info ms_hyperv; |
9279aa55 | 30 | EXPORT_SYMBOL_GPL(ms_hyperv); |
a2a47c6c | 31 | |
9df56f19 | 32 | static uint32_t __init ms_hyperv_platform(void) |
a2a47c6c | 33 | { |
e08cae41 PA |
34 | u32 eax; |
35 | u32 hyp_signature[3]; | |
a2a47c6c | 36 | |
e08cae41 | 37 | if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) |
9df56f19 | 38 | return 0; |
a2a47c6c | 39 | |
e08cae41 PA |
40 | cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS, |
41 | &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]); | |
a2a47c6c | 42 | |
9df56f19 JW |
43 | if (eax >= HYPERV_CPUID_MIN && |
44 | eax <= HYPERV_CPUID_MAX && | |
45 | !memcmp("Microsoft Hv", hyp_signature, 12)) | |
46 | return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS; | |
47 | ||
48 | return 0; | |
a2a47c6c KS |
49 | } |
50 | ||
6f4151c8 S |
51 | static cycle_t read_hv_clock(struct clocksource *arg) |
52 | { | |
53 | cycle_t current_tick; | |
54 | /* | |
55 | * Read the partition counter to get the current tick count. This count | |
56 | * is set to 0 when the partition is created and is incremented in | |
57 | * 100 nanosecond units. | |
58 | */ | |
59 | rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); | |
60 | return current_tick; | |
61 | } | |
62 | ||
63 | static struct clocksource hyperv_cs = { | |
64 | .name = "hyperv_clocksource", | |
65 | .rating = 400, /* use this when running on Hyperv*/ | |
66 | .read = read_hv_clock, | |
67 | .mask = CLOCKSOURCE_MASK(64), | |
68 | }; | |
69 | ||
e08cae41 | 70 | static void __init ms_hyperv_init_platform(void) |
a2a47c6c | 71 | { |
9e7827b5 S |
72 | u64 hv_lapic_frequency; |
73 | ||
a2a47c6c | 74 | /* |
e08cae41 | 75 | * Extract the features and hints |
a2a47c6c | 76 | */ |
e08cae41 PA |
77 | ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES); |
78 | ms_hyperv.hints = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO); | |
a2a47c6c | 79 | |
e08cae41 PA |
80 | printk(KERN_INFO "HyperV: features 0x%x, hints 0x%x\n", |
81 | ms_hyperv.features, ms_hyperv.hints); | |
6f4151c8 | 82 | |
9e7827b5 S |
83 | if (ms_hyperv.features & HV_X64_MSR_APIC_FREQUENCY_AVAILABLE) { |
84 | /* | |
85 | * Get the APIC frequency. | |
86 | */ | |
87 | rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency); | |
88 | hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ); | |
89 | lapic_timer_frequency = hv_lapic_frequency; | |
90 | printk(KERN_INFO "HyperV: LAPIC Timer Frequency: %#x\n", | |
91 | lapic_timer_frequency); | |
92 | ||
93 | /* | |
94 | * On Hyper-V, when we are booting off an EFI firmware stack, | |
95 | * we do not have many legacy devices including PIC, PIT etc. | |
96 | */ | |
97 | if (efi_enabled(EFI_BOOT)) { | |
98 | printk(KERN_INFO "HyperV: Using null_legacy_pic\n"); | |
99 | legacy_pic = &null_legacy_pic; | |
100 | } | |
101 | } | |
102 | ||
32068f65 OH |
103 | if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE) |
104 | clocksource_register_hz(&hyperv_cs, NSEC_PER_SEC/100); | |
a2a47c6c | 105 | } |
e08cae41 PA |
106 | |
107 | const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = { | |
108 | .name = "Microsoft HyperV", | |
109 | .detect = ms_hyperv_platform, | |
110 | .init_platform = ms_hyperv_init_platform, | |
111 | }; | |
96f6e775 | 112 | EXPORT_SYMBOL(x86_hyper_ms_hyperv); |
bc2b0331 S |
113 | |
114 | #if IS_ENABLED(CONFIG_HYPERV) | |
115 | static int vmbus_irq = -1; | |
116 | static irq_handler_t vmbus_isr; | |
117 | ||
118 | void hv_register_vmbus_handler(int irq, irq_handler_t handler) | |
119 | { | |
7eff7ded S |
120 | /* |
121 | * Setup the IDT for hypervisor callback. | |
122 | */ | |
123 | alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, hyperv_callback_vector); | |
124 | ||
bc2b0331 S |
125 | vmbus_irq = irq; |
126 | vmbus_isr = handler; | |
127 | } | |
128 | ||
129 | void hyperv_vector_handler(struct pt_regs *regs) | |
130 | { | |
131 | struct pt_regs *old_regs = set_irq_regs(regs); | |
132 | struct irq_desc *desc; | |
133 | ||
134 | irq_enter(); | |
135 | exit_idle(); | |
136 | ||
137 | desc = irq_to_desc(vmbus_irq); | |
138 | ||
139 | if (desc) | |
140 | generic_handle_irq_desc(vmbus_irq, desc); | |
141 | ||
142 | irq_exit(); | |
143 | set_irq_regs(old_regs); | |
144 | } | |
145 | #else | |
146 | void hv_register_vmbus_handler(int irq, irq_handler_t handler) | |
147 | { | |
148 | } | |
149 | #endif | |
150 | EXPORT_SYMBOL_GPL(hv_register_vmbus_handler); |