GNU Linux-libre 5.10.219-gnu1
[releases.git] / drivers / iommu / irq_remapping.c
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(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(msg);
160 }
161
162 /**
163  * irq_remapping_get_irq_domain - Get the irqdomain serving the request @info
164  * @info: interrupt allocation information, used to identify the IOMMU device
165  *
166  * Returns pointer to IRQ domain, or NULL on failure.
167  */
168 struct irq_domain *irq_remapping_get_irq_domain(struct irq_alloc_info *info)
169 {
170         if (!remap_ops || !remap_ops->get_irq_domain)
171                 return NULL;
172
173         return remap_ops->get_irq_domain(info);
174 }