1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | #include <linux/cpumask.h> |
3 | #include <linux/kernel.h> |
4 | #include <linux/string.h> |
5 | #include <linux/errno.h> |
6 | #include <linux/msi.h> |
7 | #include <linux/irq.h> |
8 | #include <linux/pci.h> |
9 | #include <linux/irqdomain.h> |
10 | |
11 | #include <asm/hw_irq.h> |
12 | #include <asm/irq_remapping.h> |
13 | #include <asm/processor.h> |
14 | #include <asm/x86_init.h> |
15 | #include <asm/apic.h> |
16 | #include <asm/hpet.h> |
17 | |
18 | #include "irq_remapping.h" |
19 | |
20 | int irq_remapping_enabled; |
21 | int irq_remap_broken; |
22 | int disable_sourceid_checking; |
23 | int no_x2apic_optout; |
24 | |
25 | int disable_irq_post = 0; |
26 | |
27 | static int disable_irq_remap; |
28 | static struct irq_remap_ops *remap_ops; |
29 | |
30 | static void irq_remapping_restore_boot_irq_mode(void) |
31 | { |
32 | /* |
33 | * With interrupt-remapping, for now we will use virtual wire A |
34 | * mode, as virtual wire B is little complex (need to configure |
35 | * both IOAPIC RTE as well as interrupt-remapping table entry). |
36 | * As this gets called during crash dump, keep this simple for |
37 | * now. |
38 | */ |
39 | if (boot_cpu_has(X86_FEATURE_APIC) || apic_from_smp_config()) |
40 | disconnect_bsp_APIC(virt_wire_setup: 0); |
41 | } |
42 | |
43 | static void __init irq_remapping_modify_x86_ops(void) |
44 | { |
45 | x86_apic_ops.restore = irq_remapping_restore_boot_irq_mode; |
46 | } |
47 | |
48 | static __init int setup_nointremap(char *str) |
49 | { |
50 | disable_irq_remap = 1; |
51 | return 0; |
52 | } |
53 | early_param("nointremap" , setup_nointremap); |
54 | |
55 | static __init int setup_irqremap(char *str) |
56 | { |
57 | if (!str) |
58 | return -EINVAL; |
59 | |
60 | while (*str) { |
61 | if (!strncmp(str, "on" , 2)) { |
62 | disable_irq_remap = 0; |
63 | disable_irq_post = 0; |
64 | } else if (!strncmp(str, "off" , 3)) { |
65 | disable_irq_remap = 1; |
66 | disable_irq_post = 1; |
67 | } else if (!strncmp(str, "nosid" , 5)) |
68 | disable_sourceid_checking = 1; |
69 | else if (!strncmp(str, "no_x2apic_optout" , 16)) |
70 | no_x2apic_optout = 1; |
71 | else if (!strncmp(str, "nopost" , 6)) |
72 | disable_irq_post = 1; |
73 | |
74 | str += strcspn(str, "," ); |
75 | while (*str == ',') |
76 | str++; |
77 | } |
78 | |
79 | return 0; |
80 | } |
81 | early_param("intremap" , setup_irqremap); |
82 | |
83 | void set_irq_remapping_broken(void) |
84 | { |
85 | irq_remap_broken = 1; |
86 | } |
87 | |
88 | bool irq_remapping_cap(enum irq_remap_cap cap) |
89 | { |
90 | if (!remap_ops || disable_irq_post) |
91 | return false; |
92 | |
93 | return (remap_ops->capability & (1 << cap)); |
94 | } |
95 | EXPORT_SYMBOL_GPL(irq_remapping_cap); |
96 | |
97 | int __init irq_remapping_prepare(void) |
98 | { |
99 | if (disable_irq_remap) |
100 | return -ENOSYS; |
101 | |
102 | if (intel_irq_remap_ops.prepare() == 0) |
103 | remap_ops = &intel_irq_remap_ops; |
104 | else if (IS_ENABLED(CONFIG_AMD_IOMMU) && |
105 | amd_iommu_irq_ops.prepare() == 0) |
106 | remap_ops = &amd_iommu_irq_ops; |
107 | else if (IS_ENABLED(CONFIG_HYPERV_IOMMU) && |
108 | hyperv_irq_remap_ops.prepare() == 0) |
109 | remap_ops = &hyperv_irq_remap_ops; |
110 | else |
111 | return -ENOSYS; |
112 | |
113 | return 0; |
114 | } |
115 | |
116 | int __init irq_remapping_enable(void) |
117 | { |
118 | int ret; |
119 | |
120 | if (!remap_ops->enable) |
121 | return -ENODEV; |
122 | |
123 | ret = remap_ops->enable(); |
124 | |
125 | if (irq_remapping_enabled) |
126 | irq_remapping_modify_x86_ops(); |
127 | |
128 | return ret; |
129 | } |
130 | |
131 | void irq_remapping_disable(void) |
132 | { |
133 | if (irq_remapping_enabled && remap_ops->disable) |
134 | remap_ops->disable(); |
135 | } |
136 | |
137 | int irq_remapping_reenable(int mode) |
138 | { |
139 | if (irq_remapping_enabled && remap_ops->reenable) |
140 | return remap_ops->reenable(mode); |
141 | |
142 | return 0; |
143 | } |
144 | |
145 | int __init irq_remap_enable_fault_handling(void) |
146 | { |
147 | if (!irq_remapping_enabled) |
148 | return 0; |
149 | |
150 | if (!remap_ops->enable_faulting) |
151 | return -ENODEV; |
152 | |
153 | return remap_ops->enable_faulting(); |
154 | } |
155 | |
156 | void panic_if_irq_remap(const char *msg) |
157 | { |
158 | if (irq_remapping_enabled) |
159 | panic(fmt: msg); |
160 | } |
161 | |