Commit | Line | Data |
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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> |
1aec1696 | 20 | #include <linux/irq.h> |
a2a47c6c | 21 | #include <asm/processor.h> |
e08cae41 | 22 | #include <asm/hypervisor.h> |
a2a47c6c KS |
23 | #include <asm/hyperv.h> |
24 | #include <asm/mshyperv.h> | |
bc2b0331 S |
25 | #include <asm/desc.h> |
26 | #include <asm/idle.h> | |
27 | #include <asm/irq_regs.h> | |
9e7827b5 | 28 | #include <asm/i8259.h> |
d68ce017 | 29 | #include <asm/apic.h> |
a2a47c6c | 30 | |
e08cae41 | 31 | struct ms_hyperv_info ms_hyperv; |
9279aa55 | 32 | EXPORT_SYMBOL_GPL(ms_hyperv); |
a2a47c6c | 33 | |
1aec1696 TG |
34 | #ifdef CONFIG_HYPERV |
35 | static irq_handler_t *vmbus_handler; | |
36 | ||
37 | void hyperv_vector_handler(struct pt_regs *regs) | |
38 | { | |
39 | struct pt_regs *old_regs = set_irq_regs(regs); | |
40 | ||
41 | irq_enter(); | |
42 | exit_idle(); | |
43 | ||
44 | inc_irq_stat(irq_hv_callback_count); | |
45 | if (vmbus_handler) | |
46 | vmbus_handler(); | |
47 | ||
48 | irq_exit(); | |
49 | set_irq_regs(old_regs); | |
50 | } | |
51 | ||
52 | int hv_setup_vmbus_irq(int irq, irq_handler_t *handler, void *dev_id) | |
53 | { | |
54 | vmbus_handler = handler; | |
55 | /* | |
56 | * Setup the IDT for hypervisor callback. Prevent reallocation | |
57 | * at module reload. | |
58 | */ | |
59 | if (!test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors)) | |
60 | alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, | |
61 | hyperv_callback_vector); | |
62 | } | |
63 | ||
64 | void hv_remove_vmbus_irq(unsigned int irq, void *dev_id) | |
65 | { | |
66 | /* We have no way to deallocate the interrupt gate */ | |
67 | vmbus_handler = NULL; | |
68 | } | |
69 | EXPORT_SYMBOL_GPL(hv_setup_vmbus_irq); | |
70 | EXPORT_SYMBOL_GPL(hv_remove_vmbus_irq); | |
71 | #endif | |
72 | ||
9df56f19 | 73 | static uint32_t __init ms_hyperv_platform(void) |
a2a47c6c | 74 | { |
e08cae41 PA |
75 | u32 eax; |
76 | u32 hyp_signature[3]; | |
a2a47c6c | 77 | |
e08cae41 | 78 | if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) |
9df56f19 | 79 | return 0; |
a2a47c6c | 80 | |
e08cae41 PA |
81 | cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS, |
82 | &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]); | |
a2a47c6c | 83 | |
9df56f19 JW |
84 | if (eax >= HYPERV_CPUID_MIN && |
85 | eax <= HYPERV_CPUID_MAX && | |
86 | !memcmp("Microsoft Hv", hyp_signature, 12)) | |
87 | return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS; | |
88 | ||
89 | return 0; | |
a2a47c6c KS |
90 | } |
91 | ||
6f4151c8 S |
92 | static cycle_t read_hv_clock(struct clocksource *arg) |
93 | { | |
94 | cycle_t current_tick; | |
95 | /* | |
96 | * Read the partition counter to get the current tick count. This count | |
97 | * is set to 0 when the partition is created and is incremented in | |
98 | * 100 nanosecond units. | |
99 | */ | |
100 | rdmsrl(HV_X64_MSR_TIME_REF_COUNT, current_tick); | |
101 | return current_tick; | |
102 | } | |
103 | ||
104 | static struct clocksource hyperv_cs = { | |
105 | .name = "hyperv_clocksource", | |
106 | .rating = 400, /* use this when running on Hyperv*/ | |
107 | .read = read_hv_clock, | |
108 | .mask = CLOCKSOURCE_MASK(64), | |
109 | }; | |
110 | ||
e08cae41 | 111 | static void __init ms_hyperv_init_platform(void) |
a2a47c6c | 112 | { |
a2a47c6c | 113 | /* |
e08cae41 | 114 | * Extract the features and hints |
a2a47c6c | 115 | */ |
e08cae41 PA |
116 | ms_hyperv.features = cpuid_eax(HYPERV_CPUID_FEATURES); |
117 | ms_hyperv.hints = cpuid_eax(HYPERV_CPUID_ENLIGHTMENT_INFO); | |
a2a47c6c | 118 | |
e08cae41 PA |
119 | printk(KERN_INFO "HyperV: features 0x%x, hints 0x%x\n", |
120 | ms_hyperv.features, ms_hyperv.hints); | |
6f4151c8 | 121 | |
90ab9d55 | 122 | #ifdef CONFIG_X86_LOCAL_APIC |
9e7827b5 S |
123 | if (ms_hyperv.features & HV_X64_MSR_APIC_FREQUENCY_AVAILABLE) { |
124 | /* | |
125 | * Get the APIC frequency. | |
126 | */ | |
4c08edd3 PA |
127 | u64 hv_lapic_frequency; |
128 | ||
9e7827b5 S |
129 | rdmsrl(HV_X64_MSR_APIC_FREQUENCY, hv_lapic_frequency); |
130 | hv_lapic_frequency = div_u64(hv_lapic_frequency, HZ); | |
131 | lapic_timer_frequency = hv_lapic_frequency; | |
132 | printk(KERN_INFO "HyperV: LAPIC Timer Frequency: %#x\n", | |
133 | lapic_timer_frequency); | |
134 | ||
135 | /* | |
136 | * On Hyper-V, when we are booting off an EFI firmware stack, | |
137 | * we do not have many legacy devices including PIC, PIT etc. | |
138 | */ | |
139 | if (efi_enabled(EFI_BOOT)) { | |
140 | printk(KERN_INFO "HyperV: Using null_legacy_pic\n"); | |
141 | legacy_pic = &null_legacy_pic; | |
142 | } | |
143 | } | |
90ab9d55 | 144 | #endif |
9e7827b5 | 145 | |
32068f65 OH |
146 | if (ms_hyperv.features & HV_X64_MSR_TIME_REF_COUNT_AVAILABLE) |
147 | clocksource_register_hz(&hyperv_cs, NSEC_PER_SEC/100); | |
a2a47c6c | 148 | } |
e08cae41 PA |
149 | |
150 | const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = { | |
151 | .name = "Microsoft HyperV", | |
152 | .detect = ms_hyperv_platform, | |
153 | .init_platform = ms_hyperv_init_platform, | |
154 | }; | |
96f6e775 | 155 | EXPORT_SYMBOL(x86_hyper_ms_hyperv); |